215 results on '"Murawski A"'
Search Results
2. The Influence of Etching Method on the Occurrence of Defect Levels in III-V and II-VI Materials
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Kinga Majkowycz, Krzysztof Murawski, Małgorzata Kopytko, Krzesimir Nowakowski-Szkudlarek, Marta Witkowska-Baran, and Piotr Martyniuk
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DLTS ,MOCVD ,MBE ,MCT ,T2SL ,wet etching ,Chemistry ,QD1-999 - Abstract
The influence of the etching method on the occurrence of defect levels in InAs/InAsSb type-II superlattice (T2SLs) and MCT photodiode is presented. For both analyzed detectors, the etching process was performed by two methods: wet chemical etching and dry etching using an ion beam (RIE—reactive ion etching). The deep-level transient spectroscopy (DLTS) method was used to determine the defect levels occurring in the analyzed structures. The obtained results indicate that the choice of etching method affects the occurrence of additional defect levels in the MCT material, but it has no significance for InAs/InAsSb T2SLs.
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- 2024
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3. Human Beta Defensin-2 mRNA and Proteasome Subunit β Type 8 mRNA Analysis, Useful in Differentiating Skin Biopsies from Atopic Dermatitis and Psoriasis Vulgaris Patients
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Agnieszka Terlikowska-Brzósko, Ryszard Galus, Piotr Murawski, Justyna Niderla-Bielińska, Izabela Młynarczuk-Biały, Elwira Paluchowska, and Witold Owczarek
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atopic dermatitis (AD) ,human beta defensin-2 (hBD-2) ,involucrin (IVL) ,proteasome subunit beta type 8 (PSMB8) ,psoriasis vulgaris (PV) ,tripeptidyl peptidase 2 (TPP2) ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
(1): Atopic dermatitis and psoriasis vulgaris are chronic, inflammatory diseases. Clinical presentation usually leads to a proper diagnosis, but sometimes neither clinical examination nor histopathological evaluation can be conclusive. Therefore, we aimed to build up a novel diagnostic tool and check it for accuracy. The main objective of our work was to differentiate between healthy skin (C), atopic dermatitis (AD) and psoriasis vulgaris (PV) biopsies on the base of involucrin (IVL) and human β-defensin-2 (hBD-2) concentrations and their mRNA, as well as mRNA for TPP2 and PSMB8. (2): ELISA for IVL and hBD-2 proteins and Real-time PCR for the relative expression of mRNA for: IVL (IVL mRNA), hBD-2 (hBD-2 mRNA), PSMB8 (PSMB8 mRNA) and TPP2 (TPP2 mRNA), isolated from skin biopsies taken from AD and PV patients and healthy volunteers were performed. (3): hBD-2 mRNA and PSMB8 mRNA correlated with some parameters of clinical assessment of inflammatory disease severity. hBD-2 mRNA expression, exclusively, was sufficient to distinguish inflammatory skin biopsies from the healthy ones. (4): hBD-2 mRNA and PSMB8 mRNA analysis were the most valuable parameters in differentiating AD and PV biopsies.
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- 2024
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4. Optical Characterization of the Interband Cascade LWIR Detectors with Type-II InAs/InAsSb Superlattice Absorber
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Krzysztof Murawski, Kinga Majkowycz, Małgorzata Kopytko, Tetiana Manyk, Karol Dąbrowski, Bartłomiej Seredyński, Łukasz Kubiszyn, and Piotr Martyniuk
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InAs/InAsSb ,infrared detectors ,defect states ,photoluminescence ,spectral response ,cascade infrared detectors ,Chemistry ,QD1-999 - Abstract
The long-wave infrared (LWIR) interband cascade detector with type-II superlattices (T2SLs) and a gallium-free (“Ga-free”) InAs/InAsSb (x = 0.39) absorber was characterized by photoluminescence (PL) and spectral response (SR) methods. Heterostructures were grown by molecular beam epitaxy (MBE) on a GaAs substrate (001) orientation. The crystallographic quality was confirmed by high-resolution X-Ray diffraction (HRXRD). Two independent methods, combined with theoretical calculations, were able to determine the transitions between the superlattice minibands. Moreover, transitions from the trap states were determined. Studies of the PL intensity as a function of the excitation laser power allowed the identification of optical transitions. The determined effective energy gap (Eg) of the tested absorber layer was 116 meV at 300 K. The transition from the first light hole miniband to the first electron miniband was red-shifted by 76 meV. The detected defects’ energy states were constant versus temperature. Their values were 85 meV and 112 meV, respectively. Moreover, two additional transitions from acceptor levels in cryogenic temperature were determined by being shifted from blue to Eg by 6 meV and 16 meV, respectively.
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- 2024
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5. A Step Forward in Understanding the Expression of Classical Aquaporins in the Male Reproductive Tract: Study Findings in Cattle (Bos taurus)
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Patrycja Oberska, Marta Grabowska, Marta Marynowska, Maciej Murawski, Dariusz Gączarzewicz, Andrzej Syczewski, and Katarzyna Michałek
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water channel ,male reproduction ,animal development ,testis ,rete testis ,efferent ducts ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Aquaporins (AQPs), also known as water channels, appear to be particularly promising in maintaining male reproductive potential. Therefore, this study aimed to determine the presence of classical AQPs in the bovine (Bos taurus) reproductive system and analyze changes in their expression with age using immunohistochemistry and Western blotting. Of the six classical AQPs, AQP0, AQP1, AQP4, AQP5 and AQP6 were detected, while AQP2 was absent. In the testis, AQP0 was visible in Leydig cells in selected animals, while AQP1 was found in myoid cells surrounding the seminiferous tubules of mature individuals. This characteristic expression patterns of AQP0, limited only to certain bulls, is difficult to explain unequivocally. It is possible that AQP0 expression in cattle is subject to individual variability or changes in response to specific physiological conditions. In the caput and corpus epididymis, AQP0 showed weak expression in epithelial cells of immature animals and stronger expression in basal and principal cells of reproductive bulls. In all animals, AQP1 was present on the apical surface of epithelial cells in the initial segment of the caput epididymis. AQP4, AQP5 and AQP6 were identified in principal and basal cells along the entire epididymis of reproductive bulls. The abundance of AQP4 and AQP6 increased from the caput to the cauda epididymis with the growth and development of the animals. In all males, AQP4, AQP5 and AQP6 were observed in epithelial cells of the vas deferens, and their expression in this section increased with age. In conclusion, the abundance and distribution of the classical AQPs in various cell types and parts of the male reproductive system indicate their crucial role in maintaining water homeostasis, which is essential for normal reproductive function in cattle.
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- 2024
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6. Comparative Analysis of Primary Ovarian Cancer Cells and Established Cell Lines as a New Tool for Studies on Ovarian Cancer Cell Complexity
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Agnieszka Szyposzynska, Aleksandra Bielawska-Pohl, Maria Paprocka, Julia Bar, Marek Murawski, and Aleksandra Klimczak
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ovarian cancer ,primary cells ,immortalization ,cell line ,cancer stem cells ,CD133 ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Primary cancer cells reflect the genetic background and phenotype of a tumor. Immortalized cells with higher proliferation activity have an advantage over primary cells. The aim of the study was to immortalize the primary ovarian cancer (OvCa) cells using the plasmid-carrying human telomerase reverse transcriptase (hTERT) gene and compare their phenotype and biological activity with the primary cells. The primary OvCa3 A and OvCa7 A cells were isolated from the ascitic fluid of two high-grade serous ovarian cancer patients and were characterized using immunocytochemical methods, flow cytometry, real-time RT-PCR, Western blot, metabolic activity, and migratory potential. Both immortalized ovarian cancer cell lines mirrored the phenotype of primary cancer cells, albeit with modifications. The OvCa3 A hTERT cells kept the mesenchymal stem cell phenotype of CD73/CD90/CD105-positivity and were CD133-negative, whereas the cell population of OvCa7 A hTERT lost CD73 expression, but almost 90% of cells expressed the CD133 characteristic for the CSCs phenotype. Immortalized OvCa cells differed in gene expression level with respect to Sox2 and Oct4, which was associated with stemness properties. The OvCa7 A hTERT cells showed higher metabolic and migratory activity and ALDH1 expression than the corresponding primary OvCa cells. Both primary and immortalized cell lines were able to form spheroids. The newly established unique immortalized cell line OvCa7 A hTERT, with the characteristic of a serous ovarian cancer malignancy feature, and with the accumulation of the p53, Pax8, and overexpression of the CD133 and CD44 molecules, may be a useful tool for research on therapeutic approaches, especially those targeting CSCs in ovarian cancer and in preclinical 2D and 3D models.
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- 2024
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7. Pelvic Organ Prolapse Reconstruction with the Chitosan-Based Novel Haemostatic Agent in Ovine Model—Preliminary Report
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Klaudia Stangel-Wójcikiewicz, Maciej Murawski, Tomasz Schwarz, Krzysztof Skotniczny, Agnieszka Fuchs, Jan Wolski, Julia Radwan-Pragłowska, Łukasz Janus, Marek Piątkowski, Marta Kot, Andrzej Wróbel, Dorota Wojtysiak, and Przemysław Urbaniec
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pelvic organ prolapse ,biomaterials ,animal model ,chitosan haemostatic agent ,ovine ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
This prospective study aimed to assess the feasibility of chitosan biomaterial and subcutaneous gel implantation in an ovine model, with implications for women with genital prolapse. Twenty-four ewes were divided into four groups (n = 6 per group): chitosan type B, chitosan type C, chitosan unmodified injections, and polypropylene mesh. Ovine models were chosen due to their morphological resemblance to human reproductive organs. Animals were sacrificed after 90 days for macroscopic, pathomorphological, and immunohistochemical analysis. In the chitosan type B group, IL-6 and IL-10 levels decreased after 28 days, while chitosan type C and injection groups exhibited higher IL-6 than IL-10 levels. The polypropylene group displayed the highest IL-6 and lowest IL-10 levels. Histological examination of the polypropylene group revealed no degenerative changes or inflammation, whereas chitosan injection induced local inflammation. Other groups exhibited no degenerative changes. Ewes implanted with chitosan displayed reduced inflammation compared to polypropylene-implanted ewes. Chitosan implantation facilitated vaginal tissue healing, in contrast to polypropylene mesh, which led to extrusion. While chitosan holds promise as an alternative to polypropylene mesh, further research is imperative for comprehensive evaluation. This study suggests the potential of a chitosan biomaterial in pelvic organ prolapse treatment, warranting additional investigation.
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- 2024
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8. Cellular Distribution of Aquaporin 3, 7 and 9 in the Male Reproductive System: A Lesson from Bovine Study (Bos taurus)
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Patrycja Oberska, Marta Grabowska, Marta Marynowska, Maciej Murawski, Dariusz Gączarzewicz, Andrzej Syczewski, and Katarzyna Michałek
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water channel ,morphology ,GATA-4 ,male reproductive potential ,testis ,epididymis ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The increasing incidence of male infertility in humans and animals creates the need to search for new factors that significantly affect the course of reproductive processes. Therefore, the aim of this study was to determine the temporospatial expression of aquaglyceroporins (AQP3, AQP7 and AQP9) in the bovine (Bos taurus) reproductive system using immunohistochemistry and Western blotting. The study also included morphological analysis and identification of GATA-4. In brief, in immature individuals, AQP3 and AQP7 were found in gonocytes. In reproductive bulls, AQP3 was observed in spermatocytes and spermatogonia, while AQP7 was visible in all germ cells and the Sertoli cells. AQP7 and AQP9 were detected in the Leydig cells. Along the entire epididymis of reproductive bulls, aquaglyceroporins were visible, among others, in basal cells (AQP3 and AQP7), in epididymal sperm (AQP7) and in the stereocilia of the principal cells (AQP9). In males of all ages, aquaglyceroporins were identified in the principal and basal cells of the vas deferens. An increase in the expression of AQP3 in the testis and cauda epididymis and a decrease in the abundance of AQP7 in the vas deferens with age were found. In conclusion, age-related changes in the expression and/or distribution patterns of AQP3, AQP7 and AQP9 indicate the involvement of these proteins in the normal development and course of male reproductive processes in cattle.
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- 2024
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9. Mesenchymal Stem Cell Microvesicles from Adipose Tissue: Unraveling Their Impact on Primary Ovarian Cancer Cells and Their Therapeutic Opportunities
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Agnieszka Szyposzynska, Aleksandra Bielawska-Pohl, Marek Murawski, Rafal Sozanski, Grzegorz Chodaczek, and Aleksandra Klimczak
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ovarian cancer ,primary ovarian cancer cells ,mesenchymal stem cells ,extracellular vesicles ,MSC-microvesicles ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Mesenchymal stem cells (MSCs) and their derivatives can be promising tools in oncology including ovarian cancer treatment. This study aimed to determine the effect of HATMSC2-MVs (microvesicles derived from human immortalized mesenchymal stem cells of adipose tissue origin) on the fate and behavior of primary ovarian cancer cells. Human primary ovarian cancer (OvCa) cells were isolated from two sources: post-operative tissue of ovarian cancer and ascitic fluid. The phenotype of cells was characterized using flow cytometry, real-time RT-PCR, and immunofluorescence staining. The effect of HATMSC2-MVs on the biological activity of primary cells was analyzed in 2D (proliferation, migration, and cell survival) and 3D (cell survival) models. We demonstrated that HATMSC2-MVs internalized into primary ovarian cancer cells decrease the metabolic activity and induce the cancer cell death and are leading to decreased migratory activity of tumor cells. The results suggests that the anti-cancer effect of HATMSC2-MVs, with high probability, is contributed by the delivery of molecules that induce cell cycle arrest and apoptosis (p21, tumor suppressor p53, executor caspase 3) and proapoptotic regulators (bad, BIM, Fas, FasL, p27, TRAIL-R1, TRAIL-R2), and their presence has been confirmed by apoptotic protein antibody array. In this study, we demonstrate the ability to inhibit primary OvCa cells growth and apoptosis induction after exposure of OvCa cells on HATMSC2-MVs treatment; however, further studies are needed to clarify their anticancer activities.
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- 2023
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10. Repetitive Cerulein-Induced Chronic Pancreatitis in Growing Pigs—A Pilot Study
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Ewa Tomaszewska, Małgorzata Świątkiewicz, Siemowit Muszyński, Janine Donaldson, Katarzyna Ropka-Molik, Marcin B. Arciszewski, Maciej Murawski, Tomasz Schwarz, Piotr Dobrowolski, Sylwia Szymańczyk, Sławomir Dresler, and Joanna Bonior
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pig ,chronic pancreatitis ,cerulein ,cytokines ,junction proteins ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Chronic pancreatitis (CP) is an irreversible and progressive inflammatory disease. Knowledge on the development and progression of CP is limited. The goal of the study was to define the serum profile of pro-inflammatory cytokines and the cell antioxidant defense system (superoxidase dismutase—SOD, and reduced glutathione—GSH) over time in a cerulein-induced CP model and explore the impact of these changes on selected cytokines in the intestinal mucosa and pancreatic tissue, as well as on selected serum biochemical parameters. The mRNA expression of CLDN1 and CDH1 genes, and levels of Claudin-1 and E-cadherin, proteins of gut barrier, in the intestinal mucosa were determined via western blot analysis. The study showed moderate pathomorphological changes in the pigs’ pancreas 43 days after the last cerulein injection. Blood serum levels of interleukin (IL)-1-beta, IL-6, tumor necrosis factor alpha (TNF-alpha), C-reactive protein (CRP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGTP), SOD and GSH were increased following cerulein injections. IL-1-beta, IL-6, TNF-alpha and GSH were also increased in jejunal mucosa and pancreatic tissue. In duodenum, decreased mRNA expression of CDH1 and level of E-cadherin and increased D-lactate, an indicator of leaky gut, indicating an inflammatory state, were observed. Based on the current results, we can conclude that repetitive cerulein injections in growing pigs not only led to CP over time, but also induced inflammation in the intestine. As a result of the inflammation, the intestinal barrier was impaired.
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- 2023
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11. Effects of Petroleum By-Products and Dispersants on Ecosystems
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Claire B. Paris-Limouzy, Cameron H. Ainsworth, Tracey T. Sutton, Erik E. Cordes, Richard Dodge, Markus Huettel, Irving Mendelssohn, Patrick Schwing, Kenneth M. Halanych, Steven A. Murawski, and Richard F. Shaw
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chemistry.chemical_compound ,chemistry ,Environmental protection ,Petroleum ,Environmental science ,Ecosystem ,Oceanography ,Dispersant - Abstract
Gulf of Mexico (GOM) ecosystems are interconnected by numerous physical and biological processes. After the Deepwater Horizon (DWH) disaster, these ecological processes facilitated dispersal of oil-spill toxicants or were damaged and broken. A considerable portion of post-DWH research focused on higher levels of biological organization (i.e., populations, communities, and ecosystems) spanning at least four environments (onshore, coastal, open ocean, and deep benthos). Damage wrought by the oil spill and mitigation efforts varied considerably across ecosystems. Whereas all systems show prolonged impacts because of cascading effects that impacted functional connections within and between communities, deep-sea and mesopelagic environments were particularly hard hit and have shown less resilience than shallow environments. In some environments, such as marshes or the deep-sea benthos, products from the spill are still biologically accessible. Some shallow ecosystems show signs of recovery, and populations of some species show resilience; however, a return to a “pre-spill” state is questionable. Importantly, habitats in which large amounts of energy flow through the ecosystem (marshes, coastal regions) recovered more quickly than low energy habitats (deep-sea benthos). Functional interactions between Gulf of Mexico systems are more complex and widespread than generally recognized. Moreover, ecosystems in the Gulf are subject to multiple stressors that can combine to impart greater, and less predictable, impacts. To help mitigate the effects of future insults, we identified four salient areas of research that should be addressed for each of the major environments within the GOM: establishing monitoring systems; quantifying coupling between GOM ecosystems; developing criteria for assessing the “vulnerability” and “resilience” of species, communities, and ecosystems; and developing holistic predictive modeling.
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- 2021
12. New Data Analysis Method for Time-Resolved Infrared Photoluminescence Spectroscopy
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Krzysztof Murawski and Kacper Grodecki
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010302 applied physics ,Materials science ,Photoluminescence ,Infrared ,business.industry ,Streak camera ,Infrared spectroscopy ,02 engineering and technology ,Laser pumping ,021001 nanoscience & nanotechnology ,01 natural sciences ,Signal ,chemistry.chemical_compound ,Optics ,chemistry ,0103 physical sciences ,Mercury cadmium telluride ,0210 nano-technology ,business ,Spectroscopy ,Instrumentation - Abstract
In this article, a new data treatment based on time-resolved photoluminescence is presented. It works as a streak camera for infrared. A time-resolved photoluminescence spectrum for the HgCd0.33Te0.67 sample at 120 K was performed and analyzed. Typical time-resolved photoluminescence measurements, to compare our results with literature, were conducted. An interpretation of the behavior for three different time constants found in the signal is proposed.
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- 2020
13. Application and clinical impact of the RESIST-4 O.K.N.V. rapid diagnostic test for carbapenemase detection in blood cultures and clinical samples
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Anna Nimmesgern, Niels Murawski, Sören L. Becker, Fabian K. Berger, Andreas Link, Sophie Roth, Philipp M. Lepper, and Jörg Thomas Bittenbring
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Male ,0301 basic medicine ,Microbiology (medical) ,medicine.medical_specialty ,medicine.drug_class ,Klebsiella pneumoniae ,Avibactam ,030106 microbiology ,Antibiotics ,Acute infection ,Ceftazidime ,beta-Lactamases ,Diagnostic stewardship ,03 medical and health sciences ,chemistry.chemical_compound ,Enterobacterales ,0302 clinical medicine ,Medical microbiology ,Bacterial Proteins ,Enterobacteriaceae ,Internal medicine ,Escherichia coli ,medicine ,Humans ,030212 general & internal medicine ,Clinical microbiology ,Aged ,Rapid diagnostic test ,biology ,Diagnostic Tests, Routine ,business.industry ,Brief Report ,Enterobacteriaceae Infections ,General Medicine ,Middle Aged ,biology.organism_classification ,Treatment ,Infectious Diseases ,chemistry ,Blood Culture ,Point-of-Care Testing ,Female ,business ,Bacteria ,medicine.drug - Abstract
Invasive infections caused by carbapenemase-producing bacteria are associated with excess mortality. We applied a rapid diagnostic test (RDT) on clinical samples with an elevated likelihood of carbapenemase-producing bacteria and documented its impact on antibiotic treatment decisions. Among 38 patients, twelve tested positive for infections caused by carbapenemase-producing bacteria (31.6%), mainly in blood cultures. KPC (n = 10) was more frequent than OXA-48 (n = 2). RDT-based carbapenemase detection led to a treatment modification to ceftazidime/avibactam-containing regimens in all patients before detailed antibiotic testing results became available. Eleven patients (92%) survived the acute infection, whereas one patient with a ceftazidime/avibactam- and colistin-resistant OXA-48-positive isolate died.
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- 2020
14. The effects of chicken egg white cystatin and proteinase inhibitor on cysteine peptidase-like activity in the sera of patients with breast cancer
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Marek Murawski, Anna Janocha, Lidia Hirnle, Maciej Siewinski, Teresa Skiba, Jakub Gburek, Krzysztof Gołąb, and Ewa Kilar
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Proteinase inhibitor ,Medicine (miscellaneous) ,Breast Neoplasms ,Pharmacology ,General Biochemistry, Genetics and Molecular Biology ,Cathepsin B ,Breast cancer ,Egg White ,In vivo ,Internal Medicine ,medicine ,Animals ,Humans ,Pharmacology (medical) ,Cysteine ,Genetics (clinical) ,chemistry.chemical_classification ,Chemistry ,Proteolytic enzymes ,Cancer ,medicine.disease ,Cystatins ,Enzyme ,Reviews and References (medical) ,Chickens - Abstract
Background The activity of autogenic proteolytic enzymes is regulated in vivo by autogenic inhibitors. They play important roles in maintaining a balance in many processes in the human body. In pathological conditions, enzymes are overexpressed and the balance is disturbed. Such uncontrolled changes may lead to the development of local or systemic cancer. Objectives To evaluate the effects of specific inhibitors, i.e., chicken egg white cystatin (CEWC) and proteinase inhibitor (E-64) on autogenic cysteine peptidases (CPs) in the sera of patients reporting for subsequent stages of treatment after being diagnosed with breast cancer. Cysteine peptidases play a vital role in the basic processes that are associated with cancer progression. Material and methods We selected serum samples from 108 patients with a diagnosis of breast cancer (stages IIA-IIIA) who had received no previous treatment. The blood samples were centrifuged, and the resulting serum was placed in liquid nitrogen and stored at -80°C. The biochemical tests were performed at the laboratory of the Department of Physical Chemistry and Microbiology. Results For CEWC, we found an inhibitory effect in 37 out of 108 samples; for E-64, 14 out of 22 samples displayed an inhibitory effect. In the remaining blood samples, these inhibitors caused an increase in fluorescence. In a parallel test, we added pure cathepsin B to 9 serum samples, and then used CEWC to inhibit the activity of autogenic CPs. Chicken egg white cystatin completely inhibited the cathepsin B that was added to the serum without changing its effect on the autogenic CPs. Conclusions The results suggest that there may be a potential difference between the commercially available cathepsin B and its autogenic analogues found in the serum of cancer patients. The increase in fluorescence induced in the reaction between the inhibitors and autogenic CPs is still unexplained. There was no relationship between the observed inhibition/activation of CPs and any of the available indicators of the health of the patients examined.
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- 2021
15. Lead, cadmium, mercury, and chromium in urine and blood of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V)
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Thomas Göen, Aline Murawski, Marike Kolossa-Gehring, Moritz Schäfer, Enrico Rucic, Christian Höra, Maria I.H. Schmied-Tobies, Hans Drexler, Ulrike Doyle, Jörg Hildebrand, Nina Vogel, and Alexander Kämpfe
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Chromium ,Male ,Adolescent ,Population ,chemistry.chemical_element ,Urine ,engineering.material ,Environmental health ,Germany ,Biomonitoring ,Medicine ,Humans ,education ,Child ,Cadmium ,education.field_of_study ,business.industry ,Public Health, Environmental and Occupational Health ,Environmental Exposure ,Mercury ,Mercury (element) ,Amalgam (dentistry) ,chemistry ,Lead ,Child, Preschool ,engineering ,Population study ,Environmental Pollutants ,Female ,business ,Biological Monitoring ,Environmental Monitoring - Abstract
Metals reach humans through food and drinking water intake and inhalation of airborne particles and can have detrimental health effects in particular for children. The metals presented here (lead, cadmium, chromium, and mercury) could lead to toxic effects such as neurotoxicity, mutagenicity, and have been classified as (possible) carcinogens. Using population representative data from the German Environmental Survey 2014–2017 (GerES V) from 3- to 17-year-old children on lead and cadmium in blood (n = 720) and on cadmium, chromium, and mercury in urine (n = 2250) we describe current internal exposure levels, and socio-demographic and substance-specific exposure determinants. Average internal exposure (geometric means) in blood was 9.47 μg/L for lead and below 0.06 μg/L (limit of quantification) for cadmium, and in urine 0.072 μg/L for cadmium, 0.067 μg/L for mercury, and 0.393 μg/L for chromium, respectively. Younger children have higher concentrations of lead and chromium compared to 14-17-year-old adolescents, and boys have slightly higher mercury concentrations than girls. With respect to substance specific determinants, higher lead concentrations emerged in participants with domestic fuel and in non-smoking children with smokers in the household, higher levels of cadmium were associated with smoking and vegetarian diet and higher levels of mercury with the consumption of seafood and amalgam teeth fillings. No specific exposure determinants emerged for chromium. The health based guidance value HBM-I was not exceeded for mercury and for cadmium in urine it was exceeded by 0.6% of the study population. None of the exceedances was related to substantial tobacco smoke exposure. Comparisons to previous GerES cycles (GerES II, 1990–1992; GerES IV, 2003–2006) indicate continuously lower levels.
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- 2021
16. Bioconversion of potato-processing wastes into an industrially-important chemical lactic acid
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Carlos Ricardo Soccol, Vincenza Faraco, Ariane Fátima Murawski de Mello, Cristine Rodrigues, Poonam Singh Nee Nigam, Priscilla Zwiercheczewski de Oliveira, Juliana de Oliveira, Luciana Porto de Souza Vandenberghe, de Oliveira, J., Porto de Souza Vandenberghe, L., Zwiercheczewski de Oliveira, P., Fatima Murawski de Mello, A., Rodrigues, C., Singh Nigam, P., Faraco, V., and Soccol, C. R.
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Powdered activated carbon treatment ,Environmental Engineering ,Bioconversion ,020209 energy ,Lactic acid, potato processing waste, Lactobacillus pentosus ,Bioengineering ,02 engineering and technology ,Lactobacillus pentosus ,010501 environmental sciences ,01 natural sciences ,7. Clean energy ,Hydrolysate ,12. Responsible consumption ,law.invention ,chemistry.chemical_compound ,Laboratory flask ,Erlenmeyer flask ,law ,0202 electrical engineering, electronic engineering, information engineering ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Renewable Energy, Sustainability and the Environment ,Pulp and paper industry ,Biodegradable polymer ,Lactic acid ,chemistry - Abstract
Lactic acid (LA) is an important biomolecule applied in food, pharmaceutical and chemical areas, mainly to produce biodegradable polymers, such as poly–lactic acid (PLA). In this work, an efficient fermentative process for LA production was developed using potato processing waste (PPW) hydrolysate with Lactobacillus pentosus. After optimization and kinetics studies, LA production reached 150 g/L with a productivity of 1.6 g/L.h in Erlenmeyer flasks. LA production was also conducted in STR where 110 g/L were reached with a productivity of 2.4 g/L.h. LA recovery consisted of a clarification step, with powdered activated carbon, with further precipitation at low temperature and acidification of calcium lactate for conversion to LA. The process was effective for contaminants' removal and clarification, and LA concentration to 416 g/L. Good perspectives for LA production, recovery and clarification were observed. Future studies will be carried out for LA purification and polymerization for PLA synthesis.
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- 2021
17. Alkyl pyrrolidone solvents N–methyl–2–pyrrolidone (NMP) and N–ethyl–2–pyrrolidone (NEP) in urine of children and adolescents in Germany – human biomonitoring results of the German Environmental Survey 2014–2017 (GerES V)
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Enrico Rucic, Daniel Bury, Gerda Schwedler, Monika Kasper-Sonnenberg, Aline Murawski, Marike Kolossa-Gehring, Stephan Koslitz, Thomas Brüning, Maria I.H. Schmied-Tobies, and Holger M. Koch
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Adolescent ,010504 meteorology & atmospheric sciences ,N-ethyl-2-pyrrolidone ,Population ,Urine ,010501 environmental sciences ,01 natural sciences ,Exposure ,chemistry.chemical_compound ,N-Methyl-2-pyrrolidone ,Aprotic solvent ,Germany ,Biomonitoring ,Humans ,Medicine ,Child ,education ,SVHC ,lcsh:Environmental sciences ,0105 earth and related environmental sciences ,General Environmental Science ,lcsh:GE1-350 ,education.field_of_study ,Traditional medicine ,business.industry ,fungi ,Authorization ,Pyrrolidinones ,chemistry ,Child, Preschool ,Reference values ,Alkyl pyrrolidone ,Solvents ,HBM4EU priority substance ,Reprotoxicity ,business ,Biological Monitoring ,Environmental Monitoring - Abstract
N-methyl-2-pyrrolidone (NMP) and its substitute N-ethyl-2-pyrrolidone (NEP) are aprotic solvents used in many technical applications, but also in carpets, and consumer products such as cleaning agents, and cosmetics. NMP and NEP are classified as reproductive toxicants. As a substance of very high concern (SVHC), NMP is included in the European REACH (Registration, Evaluation, Authorisation of Chemicals) candidate list for authorisation. NMP and NEP metabolites were measured in more than 2100 urine samples of 3- to 17-year-old children and adolescents, participating in the population-representative German Environmental Survey for Children and Adolescents 2014–2017 (GerES V). The two NMP metabolites 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI) could be detected and quantified in all urine samples, and the two NEP metabolites 5-hydroxy-N-ethylpyrrolidone (5-HNEP) and 2-hydroxy-N-ethylsuccinimide (2-HESI) in 32% and 87% of the urine samples. Geometric mean concentrations were 103.1 µg/L (88.21 µg/gcreatinine) for the sum of NMP metabolites and 11.86 µg/L (10.15 µg/gcreatinine) for the sum of NEP metabolites, thus remaining below the current health-based human biomonitoring values. For NMP, highest exposure was found in young children, but exposure pathways could not be revealed. Exposure to NEP was highest in adolescents and participants with low socio-economic status or migration background. Associations to usage of personal care products suggested the choice of products to have a distinct impact on NEP exposure. The presented data can be used by the German Human Biomonitoring Commission to derive new reference values (RV95) for NMP and NEP for children and adolescents in Germany. This will facilitate to recognise changing exposure levels in this population group in Germany.
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- 2021
18. Significance of Matrix Metalloproteinase 9 Expression as Supporting Marker to Cytokeratin 19 mRNA in Sentinel Lymph Nodes in Breast Cancer Patients
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Marek Murawski, Marta Woźniak, Kamila Duś-Szachniewicz, Paweł Kołodziej, Marta Rzeszutko, and Piotr Ziółkowski
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invasive breast carcinoma of no special type ,one-step nucleic acid amplification ,cytokeratin 19 ,matrix metalloproteinase 9 ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
One-step nucleic acid amplification (OSNA) detects and quantifies, with the use of a polymerase chain reaction, the presence of cytokeratin 19 mRNA in sentinel lymph nodes. The main advantage of the OSNA assay is the avoidance of second surgery in case of positive sentinel lymph node diagnosis. The objective of this study was to evaluate the significance of matrix metalloproteinase 9 expression by immunohistochemistry as supporting marker to cytokeratin 19 mRNA in sentinel lymph nodes in breast cancer patients and to relate this expression with clinicopathological data. This study was conducted on fresh sentinel lymph nodes obtained from 40 patients with tumors classified as carcinoma of no special type. The presence of metastatic cells in the slices of lymph nodes was evaluated by immunohistochemistry using antibodies for CK19 and MMP-9. Expression of CK19 and MMP-9 in lymph nodes was also confirmed by means of Western blot analysis. Results indicated that the strongest correlation with CK19 mRNA was displayed by MMP-9, CK19 (by immunohistochemistry, IHC), and nodal metastases (p < 0.001). Higher histological grading also positively correlated with CK19 mRNA, however that correlation was less significant. Since MMP-9 shows very strong correlation with CK19 mRNA in breast carcinoma of no special type metastases, expression of MMP-9 in sentinel lymph nodes should be considered as useful method whenever OSNA analysis is not available.
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- 2016
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19. Bisphenol A and six other environmental phenols in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V)
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Gerda Schwedler, Monika Kasper-Sonnenberg, Holger M. Koch, Aline Murawski, Thomas Brüning, Marike Kolossa-Gehring, Rebecca K. Moos, Carolin Tschersich, and Enrico Rucic
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Bisphenol A ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Adolescent ,Triclocarban ,Population ,Urine ,010501 environmental sciences ,01 natural sciences ,chemistry.chemical_compound ,Phenols ,Germany ,Biomonitoring ,Environmental Chemistry ,Humans ,Food science ,Benzhydryl Compounds ,education ,Child ,Waste Management and Disposal ,0105 earth and related environmental sciences ,education.field_of_study ,Chemistry ,Environmental Exposure ,Pollution ,Triclosan ,Endocrine disruptor ,Child, Preschool ,Environmental Pollutants ,Biological Monitoring ,Environmental Monitoring - Abstract
Exposure to environmental phenols such as bisphenol A, benzophenones, 2-phenylphenol, triclosan, and triclocarban is of concern, because of their endocrine disrupting properties and broad application in consumer products. The current body burden of the 3–17-year-old population in Germany to these substances was assessed in first-morning void urine samples (N = 515–516) collected within the population-representative German Environmental Survey for Children and Adolescents 2014–2017 (GerES V). Bisphenol A was the most prominent phenol analysed here, ubiquitously found in almost all samples with a geometric mean (GM) concentration of 1.905 μg/L (1.669 μg/gcreatinine) and a maximum (MAX) urinary concentration of 399 μg/L. Benzophenone-3 and benzophenone-1 were quantified in 35% and 41% of the samples. GM was below the limit of quantification (LOQ) for benzophenone-3 and 0.559 μg/L (0.489 μg/gcrea) for benzophenone-1, MAX concentrations were 845 μg/L and 202 μg/L, respectively. In 16% of the samples triclosan was found in quantifiable amounts resulting in a GM below LOQ and a MAX concentration of 801 μg/L. Benzophenone-8, 2-phenylphenol and triclocarban were quantified in none or only 1% of the samples. Benzophenone-1 and -3 concentrations were found to be associated with frequent application of personal care products. A comparison with the previous cycle of the survey, GerES IV (2003–2006), showed a decrease of urinary bisphenol A concentrations, mainly in young children. Despite this decrease, the concentration of bisphenol A exceeded the human biomonitoring (HBM) value HBM-I of 0.1 mg/L in 0.11% of the samples. For triclosan, all urinary concentrations were well below the HBM-I value of 2 mg/L. To minimise environmental health risks, it is therefore necessary to maintain a further declining trend for bisphenol A and continue monitoring the exposure to environmental phenols, as well as to monitor substitutes such as bisphenol F and S.
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- 2020
20. Associations between Mammary Gland Echotexture and Milk Composition in Cows
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P. Micek, Nina Strzałkowska, Martyna Małopolska, Patrycja Rajtar, Bahareh Ahmadi, Pawel M. Bartlewski, Nelia Scheeres, Tristan D Agustin, Tomasz Schwarz, and Maciej Murawski
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animal structures ,animal diseases ,Mammary gland ,cow ,Biology ,Article ,Milking ,chemistry.chemical_compound ,Animal science ,fluids and secretions ,image analysis ,Casein ,milk composition ,lcsh:Zoology ,medicine ,lcsh:QL1-991 ,Udder ,Lactose ,Morning ,lcsh:Veterinary medicine ,General Veterinary ,Echogenicity ,food and beverages ,ultrasonography ,Total dissolved solids ,medicine.anatomical_structure ,chemistry ,udder ,lcsh:SF600-1100 ,Animal Science and Zoology - Abstract
Thirty clinically healthy Holstein-Friesian cows underwent twice daily machine milking and ultrasonographic examinations of the udder just prior to and after milking. Digital ultrasonographic images of each udder quarter were subjected to computer-assisted echotextural analyses to obtain mean numerical pixel values (NPVs) and pixel heterogeneity (PSD) of the mammary gland parenchyma. The average milk yield and pH were higher (p <, 0.05) in the morning, whereas crude fat, total solids, solids non-fat and citric acid content were higher (p <, 0.05) during the evening milking period. Mean NPVs and PSDs of the mammary gland parenchyma were greater (p <, 0.05) after than before milking. There were significant correlations among echotextural characteristics of the udder and protein percentage, lactose content and freezing point depression determined in the milk samples collected in the morning and crude protein, casein, lactose and solids non-fat in the evening. Our results can be interpreted to suggest that computerized analysis of the mammary gland ultrasonograms has the makings of a technique for estimating non-fat milk constituents in cows. However, future validating studies are necessary before this method can be employed in commercial settings and research. Moreover, significant inter-quarter differences in udder echogenicity may necessitate further echotextural studies of separate quarters.
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- 2020
21. Citric acid bioproduction and downstream processing: Status, opportunities, and challenges
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Carlos Ricardo Soccol, Sabrina Mores, Ashok Pandey, Ariane Fátima Murawski de Mello, Júlio Cesar de Carvalho, Luciana Porto de Souza Vandenberghe, and Antonio Irineudo Magalhães Júnior
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0106 biological sciences ,Environmental Engineering ,Downstream processing ,Renewable Energy, Sustainability and the Environment ,Bioengineering ,General Medicine ,010501 environmental sciences ,Raw material ,Pulp and paper industry ,01 natural sciences ,Bioproduction ,Environmentally friendly ,Citric Acid ,chemistry.chemical_compound ,Adsorption ,Downstream (manufacturing) ,chemistry ,010608 biotechnology ,Fermentation ,Environmental science ,Citric acid ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
Citric acid (CA) has been widely used in different industrial sectors, being produced through fermentation of low-cost feedstock. The development of downstream processes, easier to operate, environmentally friendly, and more economic than precipitation, is certainly a challenge in CA bioproduction. Large volumes of by-products generated in precipitation require treatment before disposal. Adsorption, extraction, and membrane separation have been shown to have a lower environmental impact than precipitation, but the technological maturity of these methods is still limited. However, reactive extraction and adsorption have great potential for industrial applications. This review shows that there is still much to be explored, both about the factors that are intrinsic to the techniques, but also in their combination for new processes' development. This review reports the most recent advances on CA bioproduction, with significant information about recovery and purification methods involving this highly industrially demanded organic acid.
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- 2020
22. Parabens in urine of children and adolescents in Germany - human biomonitoring results of the german environmental survey 2014-2017 (GerES V)
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Carolin Tschersich, Holger M. Koch, Rebecca K. Moos, Thomas Brüning, Monika Kasper-Sonnenberg, Enrico Rucic, Gerda Schwedler, Aline Murawski, and Marike Kolossa-Gehring
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Preservative ,Adolescent ,media_common.quotation_subject ,Population ,Parabens ,Urine ,010501 environmental sciences ,01 natural sciences ,Biochemistry ,Cosmetics ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Germany ,Biomonitoring ,Ingestion ,Humans ,030212 general & internal medicine ,Food science ,education ,Child ,0105 earth and related environmental sciences ,General Environmental Science ,media_common ,education.field_of_study ,Chemistry ,Environmental Exposure ,Paraben ,Endocrine disruptor ,Child, Preschool ,Environmental Pollutants ,Biological Monitoring ,Environmental Monitoring - Abstract
Parabens are antimicrobial preservatives used in a wide range of consumer products such as personal care products, cosmetics, pharmaceuticals, and food. Consequently, the general population is ubiquitously exposed to these substances via dermal absorption, ingestion, and inhalation. Parabens promote estrogenic activity and are hence under assessment as endocrine disrupting substances. Urine samples from 3- to 17-year-old children and adolescents (N = 516) living in Germany were analysed for concentrations of nine parabens in the population representative German Environmental Survey for Children and Adolescents 2014–2017 (GerES V). Detection rates and urinary concentrations of the parabens decreased with increasing length of the alkyl chain. Methyl paraben was quantified in 97% of the samples with a geometric mean (GM) concentration of 7.724 μg/L (6.714 μg/gcreatinine), ethyl paraben was quantified in 69% (GM: 0.943 μg/L and 0.825 μg/gcrea), and n-propyl paraben in 31% (GM: 0.563 μg/L and 0.493 μg/gcrea). Concentrations of iso-propyl paraben, butyl paraben, iso-butyl paraben, and benzyl paraben were below the limit of quantification in most samples. Pentyl paraben and heptyl paraben were not detected in any of the samples. Paraben concentrations in urine were found to be associated with frequent usage of leave-on personal care products and cosmetics. Cumulative exposure to parabens (back-calculated daily intakes, expressed as hazard index) was found to be on a level raising concern in up to 14% of the population, mainly driven by n-propyl paraben, and depending on the level of conservativeness and point-of departures used for calculation.
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- 2020
23. Bovine in vitro embryo production using media prepared with Milli-Q® Water or nanowater
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Karolina Fryc, Joanna Szymanowicz, Tomasz Schwarz, Maciej Murawski, Zihui Yang, Xinyu Liu, and Pawel M. Bartlewski
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0301 basic medicine ,Cleavage Stage, Ovum ,Embryonic Development ,Fertilization in Vitro ,Cleavage (embryo) ,Andrology ,Embryo Culture Techniques ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,medicine ,Animals ,Blastocyst ,Formation rate ,030219 obstetrics & reproductive medicine ,Zygote ,Chemistry ,Milli-Q ,Ovary ,Water ,Embryo ,In vitro ,In vitro maturation ,Culture Media ,In Vitro Oocyte Maturation Techniques ,030104 developmental biology ,medicine.anatomical_structure ,embryonic structures ,Animal Science and Zoology ,Cattle ,Female ,Developmental Biology - Abstract
The aim of this study was to compare the efficiency of in vitro embryo production (IVP) following the collection of bovine ovaries and 22-h in vitro maturation (IVM) of oocytes in media prepared with Milli-Q® Water (n = 509 oocytes) or nanowater (NW; n = 304 oocytes). The mean cleavage (63.8 ± 4.6 % vs. 63.6 ± 6.1 %, respectively; mean ± SEM) and blastocyst formation rate (16.3 ± 3.4 % vs. 16.7 ± 6.7 % of presumptive zygotes, respectively) did not vary (P > 0.05; Student t-test) between the two types of media diluents. NW is a safe substitute for Milli-Q® Water for IVM of bovine oocytes.
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- 2020
24. Metabolites of 4-methylbenzylidene camphor (4-MBC), butylated hydroxytoluene (BHT), and tris(2-ethylhexyl) trimellitate (TOTM) in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey GerES V (2014-2017)
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Anja Daniels, Katja Küpper, Gabriele Leng, Enrico Rucic, Christoph Schmidtkunz, Elisabeth Eckert, Laura Kuhlmann, Gerda Schwedler, Thomas Göen, Maria I.H. Schmied-Tobies, Aline Murawski, and Marike Kolossa-Gehring
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Adolescent ,Metabolite ,Population ,Phthalic Acids ,Urine ,010501 environmental sciences ,01 natural sciences ,Biochemistry ,Benzoates ,03 medical and health sciences ,chemistry.chemical_compound ,Camphor ,0302 clinical medicine ,Germany ,Biomonitoring ,Butylated hydroxytoluene ,Medicine ,Humans ,030212 general & internal medicine ,Food science ,education ,Child ,0105 earth and related environmental sciences ,General Environmental Science ,education.field_of_study ,business.industry ,Phthalate ,Environmental Exposure ,Butylated Hydroxytoluene ,chemistry ,Endocrine disruptor ,Child, Preschool ,Environmental Pollutants ,business ,Biological Monitoring ,Environmental Monitoring - Abstract
The UV filter 4-methylbenzylidene camphor (4-MBC), used in cosmetics, the antioxidant butylated hydroxytoluene (BHT), used inter alia as a food additive and in cosmetics, and the plasticizer tris(2-ethylhexyl) trimellitate (TOTM), used mainly in medical devices as substitute for di-(2-ethylhexyl) phthalate (DEHP), are suspected to have endocrine disrupting effects. Human biomonitoring methods that allow for assessing the internal exposure of the general population to these substances were recently developed in a German cooperation to enhance the use of human biomonitoring. First-morning void urine samples from 3- to 17-year-old children and adolescents living in Germany were analysed for metabolites of 4-MBC (N = 447), BHT (N = 2091), and TOTM (N = 431) in the population-representative German Environmental Survey on Children and Adolescents 2014–2017 (GerES V). 4-MBC metabolites were found in quantifiable amounts only in single cases and exposure levels remained well below health-based guidance values. In contrast, ubiquitous exposure to BHT became evident with a geometric mean (GM) urinary concentration of the metabolite BHT acid of 2.346 μg/L (1.989 μg/gcreatinine) and a maximum concentration of 248 μg/L (269 μg/gcrea). The highest GM concentration was found in young children aged 3–5 years, yet no specific sources of exposure could be identified. Also, TOTM metabolites were found in quantifiable amounts only in very few samples. None of these findings could be related to previous hospital treatment or exposure via house dust. The presented results will be the basis to derive reference values for exposure of children and adolescents in Germany to BHT and will facilitate to identify changing exposure levels in the general population.
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- 2020
25. Photochemical Rearrangement of a 19-Membered Azoxybenzocrown: Products and their Properties
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Katarzyna Szwarc-Karabyka, Jarosław Chojnacki, Michał Kosno, Elżbieta Luboch, Natalia Łukasik, Ewa Wagner-Wysiecka, Miłosz Murawski, and Paulina Szulc
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chemistry.chemical_classification ,medicine.diagnostic_test ,010405 organic chemistry ,Chemistry ,Supramolecular chemistry ,General Chemistry ,Nuclear magnetic resonance spectroscopy ,010402 general chemistry ,Photochemistry ,Alkali metal ,01 natural sciences ,Aldehyde ,Tautomer ,0104 chemical sciences ,Yield (chemistry) ,Spectrophotometry ,medicine ,Proton NMR - Abstract
The preparation and characterization of products of the chemical and photochemical rearrangements of a 19-membered o,o'-azoxybenzocrown are presented. In photochemical rearrangement, besides the expected product i. e. 19-membered o-hydroxy-o,o'-azobenzocrown (19-o-OH) obtained under defined conditions with 75 % yield, also other macrocyclic products were isolated and identified, namely: 19-membered p-hydroxy-o,o'-azobenzocrown (19-p-OH), 21-membered o'-hydroxy-o,p'-azobenzocrown (21-o'-OH) and 19-membered macrocycle containing a 5-membered ring bearing an aldehyde group (19-al). The structures of two atypical products of the photochemical rearrangement - 21-o'-OH and 19-al - were determined in the solid state by X-ray analysis and in solution using NMR spectroscopy. Tautomeric equilibrium of the formed hydroxyazobenzocrowns and its change depending on acidity/basicity of the environment and alkali and alkaline earth metal cations complexation were studied using UV-Vis spectrophotometry, spectrofluorimetry and 1 H NMR spectroscopy.
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- 2020
26. Female rats display higher methamphetamine-primed reinstatement and c-Fos immunoreactivity than male rats
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Rick A. Bevins, Nathen J. Murawski, Steven T. Pittenger, Olivia Loh, Juan F. Duque, Scott T. Barrett, Shinnyi Chou, and Ming Li
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Cingulate cortex ,Male ,Clinical Biochemistry ,Self Administration ,Toxicology ,Biochemistry ,c-Fos ,Nucleus Accumbens ,Extinction, Psychological ,Methamphetamine ,Rats, Sprague-Dawley ,Behavioral Neuroscience ,chemistry.chemical_compound ,0302 clinical medicine ,Recurrence ,biology ,Central nucleus of the amygdala ,Immunohistochemistry ,medicine.anatomical_structure ,Female ,Proto-Oncogene Proteins c-fos ,medicine.drug ,medicine.medical_specialty ,Infralimbic cortex ,Amphetamine-Related Disorders ,Drug-Seeking Behavior ,Prefrontal Cortex ,Nucleus accumbens ,Gyrus Cinguli ,Article ,03 medical and health sciences ,Sex Factors ,Internal medicine ,medicine ,Animals ,Amphetamine ,Biological Psychiatry ,Pharmacology ,business.industry ,Central Amygdaloid Nucleus ,Meth ,030227 psychiatry ,Rats ,Disease Models, Animal ,Endocrinology ,chemistry ,biology.protein ,Central Nervous System Stimulants ,business ,030217 neurology & neurosurgery - Abstract
Methamphetamine (meth) dependence is often characterized by persistent and chronic relapse (i.e., return to drug use). Previous work suggests females may be at greater risk to relapse. In this study, we extended this limited evidence and identified sex-dependent neural substrates related to meth-triggered reinstatement. Male and female Sprague-Dawley rats were implanted with indwelling jugular catheters. Half of the rats were then trained to self-administer meth (0.05 mg/kg/inf); the other half self-administered saline during 21 daily sessions (2 h). Rats were then given 12 extinction sessions. Twenty-four hours after the last extinction session, rats received reinstatement testing. Half of the rats received a meth-prime (0.3 mg/kg, IP) injection and the remaining rats received a saline injection. This design resulted in 4 separate groups for each sex, allowing for careful investigation of brain regions related to meth-triggered reinstatement. Brains were harvested following the reinstatement session and c-Fos immunoreactivity was measured in multiple brain regions. Meth triggered reinstatement in both sexes and this effect was more robust in females compared to males. Significant sex differences were detected. Females showed greater c-Fos immunoreactivity in the cingulate cortex area 1, lateral orbitofrontal cortex, prelimbic cortex, caudate-putamen, nucleus accumbens core and shell, and central nucleus of the amygdala following meth-primed reinstatement.
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- 2020
27. A First Comprehensive Baseline of Hydrocarbon Pollution in Gulf of Mexico Fishes
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Justin Mrowicki, Maickel Armenteros, Gerardo Toro-Farmer, Susan M. Snyder, Erin L. Pulster, Steven A. Murawski, Tiffany J. Nicholson, Madison R. Schwaab, Brigid Carr, and Adolfo Gracia
- Subjects
Male ,Yellowfin tuna ,Geologic Sediments ,010504 meteorology & atmospheric sciences ,lcsh:Medicine ,Polycyclic aromatic hydrocarbon ,010501 environmental sciences ,01 natural sciences ,Demersal zone ,Article ,Water Pollution, Chemical ,Animals ,Petroleum Pollution ,Seawater ,Polycyclic Aromatic Hydrocarbons ,lcsh:Science ,Water pollution ,Tilefish ,Biliary Tract ,Mexico ,0105 earth and related environmental sciences ,chemistry.chemical_classification ,Gulf of Mexico ,Multidisciplinary ,biology ,lcsh:R ,Fishes ,Cuba ,Environmental monitoring ,Contamination ,biology.organism_classification ,Fishery ,chemistry ,Marine chemistry ,Environmental chemistry ,Florida ,Environmental science ,lcsh:Q ,Female ,Bioturbation ,Thunnus ,Water Pollutants, Chemical - Abstract
Despite over seven decades of production and hundreds of oil spills per year, there were no comprehensive baselines for petroleum contamination in the Gulf of Mexico (GoM) prior to this study. Subsequent to the 2010 Deepwater Horizon (DWH) spill, we implemented Gulf-wide fish surveys extending over seven years (2011–2018). A total of 2,503 fishes, comprised of 91 species, were sampled from 359 locations and evaluated for biliary polycyclic aromatic hydrocarbon (PAH) concentrations. The northern GoM had significantly higher total biliary PAH concentrations than the West Florida Shelf, and coastal regions off Mexico and Cuba. The highest concentrations of biliary PAH metabolites occurred in Yellowfin Tuna (Thunnus albacares), Golden Tilefish (Lopholatilus chamaeleonticeps), and Red Drum (Sciaenops ocellatus). Conversely, biliary PAH concentrations were relatively low for most other species including economically important snappers and groupers. While oil contamination in most demersal species in the north central GoM declined in the first few years following DWH, more recent increases in exposure to PAHs in some species suggest a complex interaction between multiple input sources and possible re-suspension or bioturbation of oil-contaminated sediments. This study provides the most comprehensive baselines of PAH exposure in fishes ever conducted for a large marine ecosystem.
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- 2020
28. Invisible oil beyond the Deepwater Horizon satellite footprint
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Matthew M. Alloy, Natalie Perlin, Igal Berenshtein, Steve Murawski, Samantha B. Joye, and Claire B. Paris
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010504 meteorology & atmospheric sciences ,genetic processes ,Environmental Studies ,Fishing ,information science ,010501 environmental sciences ,01 natural sciences ,Footprint ,chemistry.chemical_compound ,Oil concentration ,health care economics and organizations ,Research Articles ,0105 earth and related environmental sciences ,Multidisciplinary ,Ecology ,SciAdv r-articles ,humanities ,Fishery ,chemistry ,Deepwater horizon ,Oil spill ,health occupations ,Petroleum ,Environmental science ,Satellite ,Spatial extent ,Research Article - Abstract
A portion of the Deepwater Horizon oil spill extended beyond the satellite footprint and contained toxic oil concentrations., Major oil spills are catastrophic events that immensely affect the environment and society, yet determining their spatial extent is a highly complex task. During the Deepwater Horizon (DWH) blowout, ~149,000 km2 of the Gulf of Mexico (GoM) was covered by oil slicks and vast areas of the Gulf were closed for fishing. Yet, the satellite footprint does not necessarily capture the entire oil spill extent. Here, we use in situ observations and oil spill transport modeling to examine the full extent of the DWH spill, focusing on toxic-to-biota (i.e., marine organisms) oil concentration ranges. We demonstrate that large areas of the GoM were exposed to invisible and toxic oil that extended beyond the boundaries of the satellite footprint and the fishery closures. With a global increase in petroleum production–related activities, a careful assessment of oil spills’ full extent is necessary to maximize environmental and public safety.
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- 2020
29. The methylisothiazolinone and methylchloroisothiazolinone metabolite N-methylmalonamic acid (NMMA) in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V)
- Author
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André Conrad, Jens Bertram, Aline Murawski, Marike Kolossa-Gehring, Thomas Schettgen, Enrico Rucic, and Maria I.H. Schmied-Tobies
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Male ,Adolescent ,Metabolite ,Population ,Urine ,010501 environmental sciences ,01 natural sciences ,Isothiazolinone ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Environmental health ,Methylisothiazolinone ,Germany ,Biomonitoring ,Medicine ,Humans ,030212 general & internal medicine ,education ,Child ,0105 earth and related environmental sciences ,Exposure assessment ,education.field_of_study ,business.industry ,Public Health, Environmental and Occupational Health ,Methylchloroisothiazolinone ,Malonates ,Thiazoles ,chemistry ,Child, Preschool ,Environmental Pollutants ,Female ,business ,Haptens ,Biological Monitoring ,Disinfectants - Abstract
International journal of hygiene and environmental health 227, 113511 (2020). doi:10.1016/j.ijheh.2020.113511, Published by Elsevier, München
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- 2020
30. Exciton efficiency beyond the spin statistical limit in organic light emitting diodes based on anthracene derivatives
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Eduard Spuling, Eli Zysman-Colman, Yoann Olivier, Malte C. Gather, Ifor D. W. Samuel, Alberto Privitera, Graeme Copley, Caroline Murawski, David Hall, Alexandra M. Z. Slawin, Nidhi Sharma, David Beljonne, David B. Cordes, Francisco Tenopala-Carmona, Michael Y. Wong, The Leverhulme Trust, EPSRC, European Commission, University of St Andrews. School of Chemistry, University of St Andrews. Organic Semiconductor Centre, University of St Andrews. EaSTCHEM, University of St Andrews. School of Physics and Astronomy, University of St Andrews. Sir James Mackenzie Institute for Early Diagnosis, University of St Andrews. Centre for Biophotonics, University of St Andrews. Biomedical Sciences Research Complex, and University of St Andrews. Condensed Matter Physics
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Anthracene ,Materials science ,Carbazole ,Exciton ,DAS ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,QD Chemistry ,7. Clean energy ,01 natural sciences ,Fluorescence ,Molecular physics ,Acceptor ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Excited state ,Materials Chemistry ,OLED ,QD ,0210 nano-technology ,Spin (physics) - Abstract
E.Z.-C. acknowledges the University of St Andrews and the Leverhulme Trust (RPG- 2016-047) for financial support. E.Z.-C. and I.D.W.S. thank EPSRC (EP/P010482/1) for support. We thank EPSRC UK National Mass Spectrometry Facility at Swansea University for analytical services. The work in Mons was supported by the European Union’s Horizon 2020 research and innovation program under Grant Agreement N°. 646176 (EXTMOS project). Computational resources have been provided by the Consortium des Équipements de Calcul Intensif (CÉCI), funded by the Fonds de la Recherche Scientifiques de Belgique (F.R.S.- FNRS) under Grant No. 2.5020.11. C.M. and G.C acknowledge funding by the European Commission through a Marie Skłodowska Curie fellowship (No. 703387 and 799302, respectively). M.C.G. acknowledges funding from EPSRC (EP/R010595/1). A.P. acknowledges the European Union’s Horizon 2020 research and innovation programme under Marie Sklodowska Curie Grant agreement No. 722651 (SEPOMO project). EPR measurements were performed in the Centre for Advanced ESR (CAESR), located in the Department of Chemistry of the University of Oxford, and this work was supported by the EPSRC (EP/L011972/1). We report two donor-acceptor (D-A) materials based on a cyanoanthracene acceptor paired with diphenylamine ( DPAAnCN ) and carbazole ( CzAnCN ) donor moieties. These compounds show hybrid locally excited (LE) charge-transfer (CT) excited states (HLCT), which we demonstrated through a combined photophysical and computational study. Vacuum- deposited organic light emitting diodes (OLEDs) using these HLCT emitters exhibit maximum external quantum efficiencies (EQEmax) close to 6%, with impressive exciton utilization efficiency (Φs) of >50%, far exceeding the spin statistic limit of 25%. We rule out triplet-triplet annihilation and thermally activated delayed fluorescence as triplet harvesting mechanisms along with horizontal orientation of emitters to enhance light outcoupling and, instead, propose a “hot exciton” channel involving the nearly isoenergetic T2 and S1 states. Postprint
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- 2020
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31. Organic Light‐Emitting Diodes Based on a Columnar Liquid‐Crystalline Perylene Emitter
- Author
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Malte C. Gather, Heinz Kitzerow, Emily Archer, Harald Bock, Chang-Min Keum, Caroline Murawski, David Becker, Organic Semiconductor Centre [St Andrews] (OSC), School of Chemistry [University of St Andrews], University of St Andrews [Scotland]-University of St Andrews [Scotland]-SUPA School of Physics and Astronomy [University of St Andrews], University of St Andrews [Scotland]-Scottish Universities Physics Alliance (SUPA)-Scottish Universities Physics Alliance (SUPA), Department Chemie Paderborn University, Centre de Recherche Paul Pascal (CRPP), Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), University of Paderborn, University of St Andrews. Sir James Mackenzie Institute for Early Diagnosis, University of St Andrews. Centre for Biophotonics, University of St Andrews. Biomedical Sciences Research Complex, and University of St Andrews. School of Physics and Astronomy
- Subjects
Materials science ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,chemistry.chemical_compound ,OLED ,Perylene ,QC ,ComputingMilieux_MISCELLANEOUS ,Common emitter ,Discotic liquid crystals ,Liquid crystalline ,Discotic liquid crystal ,Transition dipole moment orientation ,DAS ,[CHIM.MATE]Chemical Sciences/Material chemistry ,021001 nanoscience & nanotechnology ,Engineering physics ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,QC Physics ,chemistry ,Christian ministry ,0210 nano-technology ,High brightness - Abstract
Funding: UK EPSRC NSF-CBET lead agency agreement (EP/R010595/1, 1706207). C.K. acknowledges support from the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2017R1A6A3A03012331). Liquid crystalline materials possess great potential as emitters in organic light-emitting diodes (OLEDs) due to their self-assembling property, which may lead to anisotropic films and improved charge transport. Here, we investigate key photophysical properties of the columnar liquid crystalline emitter perylene-3,4,9,10-tetracarboxylic tetraethyl ester (PTCTE) and implement the material into OLEDs. We find that vacuum-deposited PTCTE films exhibit preferential horizontal orientation of the transition dipole moment. Embedding the emitter into different host materials leads to increased photoluminescence quantum yield but reduces molecular orientation compared to the neat film. OLEDs containing PTCTE doped into an exciplex-forming co-host achieve very high luminance exceeding 10,000 cd m-2 at 5.7 V, which is amongst the best performance of OLEDs based on columnar liquid crystalline emitters reported so far. Publisher PDF
- Published
- 2020
32. Are the spectral Doppler indices of ovarian arteries indicative of antral follicular development and predictive of ovulatory responses and embryo yields in superovulated ewes?
- Author
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Maciej Murawski, Jeferson Ferreira da Fonseca, Maria Emilia Franco Oliveira, Mark Jamieson, Joanna Maria Gonçalves Souza-Fabjan, Ada Cristescu, Naiara Nantes Rodrigues, Wilter Ricardo Russiano Vicente, Pawel M. Bartlewski, Gabriel Brun Vergani, Universidade Estadual Paulista (Unesp), Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Fluminense Fed Univ, Univ Guelph, and Agr Univ Krakow
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0301 basic medicine ,Superovulation ,Biology ,Ovarian artery ,Andrology ,03 medical and health sciences ,Follicle ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,medicine.artery ,Follicular phase ,medicine ,Animals ,030219 obstetrics & reproductive medicine ,Sheep ,Ovary ,Embryo ,Uterine horns ,Arteries ,Antral follicle ,Doppler ultrasonography ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,Vascular resistance ,Estradiol benzoate ,Animal Science and Zoology ,Female ,Developmental Biology - Abstract
Made available in DSpace on 2020-12-10T20:07:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-12-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Department of Biomedical Sciences, U of G Embrapa Goats and Sheep Nineteen ewes received 200 mg of pFSH administered in eight decreasing doses from Days 1 to 4, starting three days before CIDR (R) device removal. Ten ewes received an injection of 350 mu g of estradiol benzoate at CIDR (R) device insertion (Group E) and nine animals served as controls (Group C). B-mode and spectral Doppler ultra-sonographic examinations were performed daily throughout superovulatory treatment to enumerate ovarian antral follicles and to determine ovarian blood flow indices, respectively. There were no differences (P > 0.05) in superovulatory responses between left and right ovaries/uterine horns or the two groups of animals. End-diastolic velocity (EDV) and mean velocity (Vm) values were greater (P < 0.05) on Days 1 and 2, and peak systolic velocity (SVp) was greater (P < 0.05) on Day 3 in Group C than in Group E. In Group E 15 correlations was recorded among indices (SVp, Vm, EDV, flow velocity integral-FVI, and pulsatility index-PI) and follicles numbers in different size classes on Days 1, 2 and 4, and seven correlations among indices (SVp, EDV, Vm, and vascular resistance index-RI) and superovulatory/embryo results (numbers of regressing corpora lutea, numbers/percentages of degenerated embryos and viability rates) on Days 1, 2 and 3. In Group C, there were three correlations among EDV and RI and medium-sized/large follicle numbers on Days 1 and 3, and five correlations among indices (EDV, RI and PI) and superovulatory/embryo results (numbers of luteinized unovulated follicles, degenerated embryos and unfertilized eggs) on Days 2 or 4. There was a lack of consistency in the velocimetric correlates of antral follicle numbers and superovulatory responses between the left and right side. Therefore, the usefulness of ovarian arterial indices to predict ovine superovulatory outcomes remains equivocal and requires further confirmatory studies. Sao Paulo State Univ, Sch Agr & Vet Sci, Dept Prevent Vet Med & Anim Reprod, BR-14884900 Jaboticabal, SP, Brazil Brazilian Agr Res Corp, Embrapa Goats & Sheep, BR-36155000 Coronel Pacheco, MG, Brazil Fluminense Fed Univ, Fac Vet Med, BR-24230340 Niteroi, RJ, Brazil Univ Guelph, Dept Biomed Sci, Ontario Vet Coll, Guelph, ON N1G 2W1, Canada Agr Univ Krakow, Dept Anim Biotechnol, Krakow, Poland Sao Paulo State Univ, Sch Agr & Vet Sci, Dept Prevent Vet Med & Anim Reprod, BR-14884900 Jaboticabal, SP, Brazil CNPq: 150896/2012-3 Embrapa Goats and Sheep: Superovi - 22.13.06.026.00.03
- Published
- 2019
33. Storage of boar semen at 16-18 °C in the long-term commercial extender prepared with deionized water or nanowater
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Joanna Szymanowicz, Zdzisław Oszczęda, Jacek Nowicki, Maciej Murawski, Ryszard Tuz, Pawel M. Bartlewski, Martyna Małopolska, and T. Schwarz
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pig ,endocrine system ,liquid storage ,General Veterinary ,BOAR ,Chemistry ,urogenital system ,nanowater ,Extender ,Plasma treatment ,Diluent ,Sperm ,sperm ,law.invention ,Boar semen ,Semen extender ,fluids and secretions ,law ,Alkaline phosphatase ,Original Article ,Animal Science and Zoology ,Food science ,semen extender - Abstract
The aim of this study was to assess the usefulness of nanowater (NW; water declusterized using cold plasma treatment) as a diluent for a commercial boar semen extender during the 15-day storage (Days 1 to 15) at 16-18 °C. Ejaculates collected from 8 boars were subjected to the standard evaluation and then diluted in the extender prepared with deionized water (DW) or NW to a final concentration of 3×109 spermatozoa/ml. The proportion of defective spermatozoa increased (P0.05) between the two groups in the concentrations of alkaline phosphatase and aspartate aminotransferase in semen extender. To summarize, the use of NW as an extender diluent exerts cytoprotective effects on boar spermatozoa and delays a decline in sperm progressive motility.
- Published
- 2019
34. Determination of trace elements in urine by inductively coupled plasma-tandem mass spectrometry – Biomonitoring of adults in the German capital region
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Peter Kujath, Aline Murawski, Marike Kolossa-Gehring, and Andy Schmied
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Adult ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Population ,Urine ,Mass spectrometry ,Tandem mass spectrometry ,Tandem Mass Spectrometry ,Biomonitoring ,Humans ,Environmental Chemistry ,education ,Metalloids ,Detection limit ,education.field_of_study ,Chromatography ,Chemistry ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Pollution ,Trace Elements ,Cross-Sectional Studies ,Metalloid ,Inductively coupled plasma ,Biological Monitoring - Abstract
A method was developed and validated for multi-element analyses of human urine samples using inductively coupled plasma-tandem mass spectrometry. The combination of a simple sample preparation and the state-of-the-art technique allows high-throughput and lowest limits of quantification up to 1 ng/L. Thereby coefficients of variation ranges from 0.4% (V) to 3.7% (Be), and 0.9% (Cd) to 4.8% (Ni) for intraday and interday precision, respectively. The method's performance is demonstrated by successful participation in international interlaboratory comparison programs as external quality assurance. Moreover, the method was applied for the analysis of first-morning void urine samples of adults (N = 77) living in the German capital region. 15 metals and metalloids (Astotal, Be, Bi, Cd, Co, Cr, In, Mn, Mo, Ni, Pb, Sn, Tl, V, and Zn) were determined. With exception of indium, all elements were found in urine samples above the limit of quantification, demonstrating the suitability to measure the general population's exposure to these metals and metalloids. The method presented here shall be used for analysis of urine samples collected in the upcoming German Environmental Survey, GerES VI, a cross-sectional, population-representative study.
- Published
- 2021
35. Sample preparation for MALDI mass spectrometry using an elastomeric device reversibly sealed on the MALDI target
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Chen, Xiaoxi, Murawski, Anthony, Kuang, Guannan, Sexton, Daniel J., and Galbraith, William
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Mass spectrometry -- Research ,Hydrophobic effect -- Research ,Ionization -- Analysis ,Peptides -- Structure ,Peptides -- Properties ,Chemistry - Abstract
A new method for improving low-concentration sample recovery and reducing sample preparation steps in matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) is presented. In the conventional approach, samples are typically desalted and/or concentrated with various techniques and deposited on the MALDI target as small droplets. In this work, we describe a new approach in which an elastomeric device is reversibly sealed on the MALDI target to form a multi-well plate with the MALDI target as the base of the plate. The new format allows a larger volume (5-200 [micro]L) of samples to be deposited on each spot and a series of sample handling processes, including desalting and concentrating, to be performed directly on the MALDI target. Several advantages have been observed: (i) multiple sample transferring steps are avoided; (ii) recovery of low-concentration peptides during sample preparation is improved using a novel desalting method that utilizes the hydrophobic surface of the elastomeric device; and (iii) sequence coverage of the peptide mass fingerprinting map is improved using a novel method in which proteins are immobilized on the hydrophobic surface of the elastomeric device for in-well trypsin digestion, followed by desalting and concentrating the digestion products in the same well.
- Published
- 2006
36. Deep-Blue Oxadiazole-Containing Thermally Activated Delayed Fluorescence Emitters for Organic Light-Emitting Diodes
- Author
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Graeme Copley, Wenbo Li, Gordon J. Hedley, David Beljonne, Caroline Murawski, Luca Muccioli, David Hall, Simonas Krotkus, Alexandra M. Z. Slawin, Juan Carlos Sancho-García, Yoann Olivier, Malte C. Gather, Michael Y. Wong, Eli Zysman-Colman, Ifor D. W. Samuel, Marie Jaricot, David B. Cordes, Mónica Moral, Universidad de Alicante. Departamento de Química Física, Química Cuántica, Michael Y. Wong, Simonas Krotkus, Graeme Copley, Wenbo Li, Caroline Murawski, David Hall, Gordon J. Hedley, Marie Jaricot, David B. Cordes, Alexandra M. Z. Slawin, Yoann Olivier, David Beljonne, Luca Muccioli, Monica Moral, Juan-Carlos Sancho-Garcia, Malte C. Gather, Ifor D. W. Samuel, and Eli Zysman-Colman, EPSRC, European Commission, University of St Andrews. School of Physics and Astronomy, University of St Andrews. School of Chemistry, University of St Andrews. EaSTCHEM, University of St Andrews. Biomedical Sciences Research Complex, and University of St Andrews. Condensed Matter Physics
- Subjects
thermally activated delayed fluorescence ,Photoluminescence ,Materials science ,Oxadiazole ,DFT calculation ,02 engineering and technology ,Organic light emitting diodes ,010402 general chemistry ,Photochemistry ,DFT calculations ,01 natural sciences ,chemistry.chemical_compound ,OLED ,General Materials Science ,QD ,Química Física ,Common emitter ,organic light emitting diode ,Oxadiazoles ,Thermally activated delayed fluorescence ,Doping ,blue emitter ,DAS ,Blue emitters ,021001 nanoscience & nanotechnology ,QD Chemistry ,Fluorescence ,Acceptor ,0104 chemical sciences ,chemistry ,Quantum efficiency ,Materials Science (all) ,0210 nano-technology ,oxadiazole - Abstract
A series of four novel deep-blue to sky-blue thermally activated delayed fluorescence (TADF) emitters (2CzdOXDMe, 2CzdOXD4MeOPh, 2CzdOXDPh, and 2CzdOXD4CF3Ph) have been synthesized and characterized. These oxadiazole-based emitters demonstrated bluer emission compared with the reference emitter 2CzPN thanks to the weaker acceptor strength of the oxadiazole moieties. The oxadiazole compounds doped in hosts (mCP and PPT) emitted from 435 to 474 nm with photoluminescence quantum yields ranging from 14–55%. The emitters possess singlet–triplet excited-state energy gaps (ΔEST) between 0.25 and 0.46 eV resulting in delayed components ranging from 4.8 to 25.8 ms. The OLED device with 2CzdOXD4CF3Ph shows a maximum external quantum efficiency of 11.2% with a sky-blue emission at CIE of (0.17, 0.25), while the device with 2CzdOXD4MeOPh shows a maximum external quantum efficiency of 6.6% with a deep-blue emission at CIE of (0.15, 0.11). E.Z.-C. thanks the University of St Andrews for support. We are grateful to the EPSRC for financial support (grants EP/P010482/1, EP/J01771X, and EP/J00916). I.D.W.S. is a Royal Society Wolfson Research Merit Award Holder. We thank the EPSRC UK National Mass Spectrometry Facility at Swansea University for analytical services. C.M. acknowledges funding by the European Commission through a Marie Skłodowska Curie Individual Fellowship (No. 703387). G.C. acknowledges funding by the European Commission through a Marie Skłodowska Individual Fellowship (No. 799302).
- Published
- 2018
37. Substitutes mimic the exposure behaviour of REACH regulated phthalates – A review of the German HBM system on the example of plasticizers
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Till Weber, Malgorzata Debiak, Holger M. Koch, Petra Apel, Rosa Lange, Aline Murawski, Marike Kolossa-Gehring, and Nora Lemke
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Population ,Phthalic Acids ,Cumulative Exposure ,Risk management tools ,010501 environmental sciences ,01 natural sciences ,German ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Plasticizers ,Surveys and Questionnaires ,Environmental health ,Biomonitoring ,Humans ,Medicine ,030212 general & internal medicine ,Child ,education ,0105 earth and related environmental sciences ,education.field_of_study ,business.industry ,Public Health, Environmental and Occupational Health ,Plasticizer ,Environmental Exposure ,language.human_language ,Cross-Sectional Studies ,chemistry ,DPHP ,Child, Preschool ,language ,Environmental Pollutants ,Risk assessment ,business ,Biological Monitoring - Abstract
The population is constantly exposed to potentially harmful substances present in the environment, including inter alia food and drinking water, consumer products, and indoor air. Human biomonitoring (HBM) is a valuable tool to determine the integral, internal exposure of the general population, including vulnerable subgroups, to provide the basis for risk assessment and policy advice. The German HBM system comprises of five pillars: (1) the development of suitable analytical methods for new substances of concern, (2) cross-sectional population-representative German Environmental Surveys (GerES), (3) time trend analyses using archived samples from the Environmental Specimen Bank (ESB), (4) the derivation of health-based guidance values as a risk assessment tool, and (5) transfer of data into the European cooperation network HBM4EU. The goal of this paper is to present the complementary elements of the German HBM system and to show its strengths and limitations on the example of plasticizers. Plasticizers have been identified by EU services and HBM4EU partners as priority substances for chemical policy at EU level. Using the complementary elements of the German HBM system, the internal exposure to classical phthalates and novel alternative plasticizers can be reliably monitored. It is shown that market changes, due to regulation of certain phthalates and the rise of substitutes, are rapidly reflected in the internal exposure of the population. It was shown that exposure to DEHP, DiBP, DnBP, and BBzP decreased considerably, whereas exposure to the novel substitutes such as DPHP, DEHTP, and Hexamoll®DINCH has increased significantly. While health-based guidance values for several phthalates (esp. DnBP, DiBP, DEHP) were exceeded quite often at the turn of the millennium, exceedances today have become rarer. Still, also the latest GerES reveals the ubiquitous and concurrent exposures to many plasticizers. Of concern is that the youngest children showed the highest exposures to most of the investigated plasticizers and in some cases their levels of DiBP and DnBP still exceeded health-based guidance values. Over the last years, mixture exposures are increasingly recognized as relevant, especially if the toxicological modes of action are similar. This is supported by a cumulative risk assessment for four endocrine active phthalates which confirms the still concerning cumulative exposure in many young children. Given the adverse health effects of some phthalates and the limited toxicological knowledge of substitutes, exposure reduction and surveillance are needed on German and EU-level. Substitutes need to be monitored, to intervene if exposures are threatening to exceed acceptable levels, or if new toxicological data question their appropriateness. It is strongly recommended to reconsider the use of plastics and plasticizers.
- Published
- 2021
38. Pentachlorophenol and nine other chlorophenols in urine of children and adolescents in Germany – Human biomonitoring results of the German Environmental Survey 2014–2017 (GerES V)
- Author
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Aline Murawski, Enrico Rucic, Marike Kolossa-Gehring, Gerda Schwedler, Maria I.H. Schmied-Tobies, Lukas Schmidt, Petra Apel, and Thomas Göen
- Subjects
Biocide ,Preservative ,Pentachlorophenol ,Adolescent ,Urine ,010501 environmental sciences ,01 natural sciences ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Germany ,Biomonitoring ,Humans ,Ingestion ,030212 general & internal medicine ,Child ,0105 earth and related environmental sciences ,General Environmental Science ,Chlorophenol ,Pesticide ,chemistry ,Environmental chemistry ,Environmental Pollutants ,Biological Monitoring ,Chlorophenols - Abstract
Chlorophenols comprise of a large group of chemicals used inter alia for the production of biocides, pharmaceuticals, other industrial products and are used e.g. as antiseptics or wood preservatives due to their biocidal properties. Several of them are classified as toxic to aquatic life and harmful to humans by ingestion, inhalation, or dermal contact, causing skin and eye irritation. Moreover, chlorophenols are possibly carcinogenic to humans. The most prominent chlorophenol – pentachlorophenol – is carcinogenic to humans, was banned in Germany in 1989 and further regulated by the European Commission in 2006 and included in the Stockholm Convention in 2017. Some chlorophenols are persistent in the environment and are also biodegradation products of precursor substances. To evaluate the health-relevance of recent exposure and monitor the effectiveness of regulatory measures, chlorophenols were analysed in the population-representative German Environmental Survey on Children and Adolescents 2014–2017 (GerES V). First-morning void urine samples of 485 3-17-year-old children and adolescents were analysed for ten chlorophenols. Pentachlorophenol was still quantified in 87% of the children and adolescents with a geometric mean (GM) concentration of 0.19 μg/L (0.16 μg/gcrea) and a maximum concentration of 6.7 μg/L (5.4 μg/gcrea). The maximum concentration was well below the health-based guidance value HBM-I of 25 μg/L (20 μg/gcrea). 4-Monochlorophenol was quantified in all samples with a GM concentration of 1.38 μg/L (1.14 μg/gcrea). 2-Monochlorophenol, 2,4-dichlorophenol, and 2,5-dichlorophenol were quantified in 97%, 98%, and 95% of the samples, with GMs of 0.26 μg/L (0.21 μg/gcrea), 0.24 μg/L (0.20 μg/gcrea), and 0.26 μg/L (0.21 μg/gcrea). 2,6-dichlorophenol, 2,3,4-trichlorophenol, and 2,4,5-trichlorophenol were quantified in 17–25% of the samples with GMs below the limit of quantification (LOQ) of 0.1 μg/L 2,4,6-trichlorophenol was quantified in 72% of the samples (GM: 0.13 μg/L, 0.11 μg/gcrea), 2,3,4,6-tetrachlorophenol in 44% of the samples (GM
- Published
- 2021
39. Species-specific metabolism of naphthalene and phenanthrene in 3 species of marine teleosts exposed to Deepwater Horizon crude oil
- Author
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Kevan L. Main, Dana L. Wetzel, Erin L. Pulster, and Steve Murawski
- Subjects
0106 biological sciences ,biology ,Southern flounder ,Ecology ,010604 marine biology & hydrobiology ,Health, Toxicology and Mutagenesis ,010501 environmental sciences ,Phenanthrene ,biology.organism_classification ,01 natural sciences ,Trachinotus carolinus ,chemistry.chemical_compound ,Biotransformation ,Paralichthys lethostigma ,chemistry ,Environmental chemistry ,Pompano ,Environmental toxicology ,Environmental Chemistry ,0105 earth and related environmental sciences ,Naphthalene - Abstract
The 2 most abundant polycyclic aromatic hydrocarbons (PAHs) measured in Deepwater Horizon crude oil, naphthalene and phenanthrene, and their associated homologs have both been shown to be acutely toxic in fish. Although fish have a relatively high metabolic capacity for PAHs, hydroxylated PAH (OH-PAH) derivatives formed during the initial metabolic response can negatively impact the health of fish. Species-specific metabolism of naphthalene and phenanthrene was evaluated in 3 marine teleosts, red drum (Scianops ocellatus), Florida pompano (Trachinotus carolinus), and southern flounder (Paralichthys lethostigma). Fish were exposed to Deepwater Horizon crude oil by intraperitoneal injections at time 0 and 48 h, with bile sampling events at 24 and 72 h post injection. The data suggested metabolic induction in Florida pompano and red drum, whereas southern flounder may have demonstrated metabolic fatigue. By 24 h post injection, overall profiles of red drum and southern flounder were dominated by hydroxylated phenanthrene metabolites; conversely, the Florida pompano profiles were dominated by monohydroxylated naphthalenes. In addition, Florida pompano had faster overall relative biotransformation rates, suggesting their potential decreased susceptibility to adverse effects. Red drum and southern flounder had much lower relative biotransformation rates, indicating their probable susceptibility to adverse outcomes after naphthalene and phenanthrene exposures. To our knowledge, the present study is the first to investigate monohydroxylated PAHs in fish exposed to Deepwater Horizon oil. Environ Toxicol Chem 2017;36:3168-3176. © 2017 © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
- Published
- 2017
40. Lithium Mobility in Borate and Phosphate Glass Networks
- Author
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Anna-Maria Welsch, Harald Behrens, Ingo Horn, and Dawid Murawski
- Subjects
Materials science ,Inorganic chemistry ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Phosphate glass ,chemistry ,Lithium ,Physical and Theoretical Chemistry ,0210 nano-technology ,Boron - Abstract
In order to improve our understanding of the Li-mobility in oxide glass networks with Li as the principle mobile particle, electrical conductivity and self-diffusivity of lithium was studied in two phosphate (0.2 Li2O·0.8 P2O5, 0.3 Li2O·0.2 MgO·0.5 P2O5) and one borate (0.25 Li2O·0.75 B2O3) glass compositions. Conductivity measurements provided information about ion dynamics while isotope-exchange experiments involving isotopically enriched Li diffusion glass couples provided information about long-range diffusivity of Li-isotopes through borate and phosphate networks. Due to the limitations of individual glass stabilities, the temperature range for selected experiments was very small, e.g. as in the case of Li–phosphate composition between 373 and 520 K. The activation energy for Li-migration derived from conductivity measurements was similar for Li–Mg–phosphate and Li–borate, 90.4 and 85.2 kJ/mol, while for pure Li–phosphate the value was 74.7 kJ/mol. In the case of self-diffusion, the activation energies were comparable with Li–Mg–phosphate having the highest value of 76.9 kJ/mol while Li–phosphate and Li–borate had almost the same value of 72.9 and 72.2 kJ/mol, respectively. In these glass compositions with similar Li-cation concentration, the differences in the mobility predominantly depend on structural arrangement of building units and the spatial distribution of negative potentials, as reflected in the value of H R/f, i.e. the Haven ratio divided by the correlation factor, as a mean to better understand the diffusion mechanism in glass structures, where vacancy vs. interstitial diffusion cannot be clearly defined. For Li–phosphate almost unconstrained Li-migration was indicated with the H R/f value of 0.98, while Li–Mg–phosphate had the most structural constraint on mobilized Li-cations, with the H R/f value of 0.30. Findings are compared with silicate (Li2O·3 SiO2) and aluminosilicate (Li2O·Al2O3·4 SiO2) glasses from our previous studies in order to elaborate the effect of network topology.
- Published
- 2017
41. Evaluation of selected immunological parameters and the concentration of vitamin D in children with asthma. Case-control study
- Author
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Agata Wawrzyniak, Piotr Murawski, Agnieszka Lipińska-Opałka, Robert Zdanowski, Sławomir Lewicki, and Bolesław Kalicki
- Subjects
Vitamin ,Spirometry ,vitamin D ,Immunology ,lcsh:Medicine ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Immune system ,immune system diseases ,0502 economics and business ,Vitamin D and neurology ,Immunology and Allergy ,Medicine ,Asthma ,medicine.diagnostic_test ,business.industry ,Incidence (epidemiology) ,flow cytometry ,05 social sciences ,lcsh:R ,Case-control study ,FOXP3 ,asthma ,medicine.disease ,respiratory tract diseases ,regulatory T cells (FoxP3) ,chemistry ,Clinical Immunology ,050211 marketing ,business ,030215 immunology - Abstract
Due to the increased incidence of allergic diseases and emerging effects of unsatisfactory control of asthma, new mechanisms for supervising the immune system should be searched. The aim of the study was to analyze the percentage of CD3, CD4, CD8, CD19, CD16/56, NKT, CD3 anti-HLADR3 and Foxp3 regulatory lymphocytes in patients with asthma. Additionally the correlation between immune parameters, severity of asthma and serum concentration of vitamin D was performed. 25 children diagnosed with asthma were enrolled. Disease severity was assessed with the Asthma Control Test (ACT) and spirometry. The control group consisted of 15 healthy children. Venous blood from each patient was collected on EDTA or on “clott”. Phenotypes of lymphocytes were evaluated by flow cytometry. Vitamin D concentration was assessed by chemiluminescent immunoassay (CLIA) technology. There was a significant decrease in the percentage of T regulatory cells (p < 0.006) in children with asthma compared to the control group. There were no significant differences in the other investigated immunological parameters. In addition, in asthma group statistically significant decreased of vitamin D concentration (p < 0.04) was observed. There were also no significant correlations between vitamin D3 concentration and the course of asthma or percentage of regulatory cells. The results confirmed the role of regulatory T cells in the pathogenesis of asthma. Effects of vitamin D on the severity of the disease has not been proven.
- Published
- 2017
42. Platelet-Rich Plasma and Hyaluronic Acid Are Not Synergistic When Used as Biological Adjuncts with Autologous Osteochondral Transplantation
- Author
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Amgad M. Haleem, Huong T. Do, Niall A. Smyth, Charles P. Hannon, John G. Kennedy, Christopher D. Murawski, and Keir A. Ross
- Subjects
Cartilage, Articular ,Male ,Pathology ,medicine.medical_specialty ,Scoring system ,animal diseases ,medicine.medical_treatment ,Biomedical Engineering ,Physical Therapy, Sports Therapy and Rehabilitation ,Articular cartilage ,Transplantation, Autologous ,Injections, Intra-Articular ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Clinical Papers ,Hyaluronic acid ,medicine ,Animals ,Immunology and Allergy ,Hyaluronic Acid ,Cartilage repair ,Saline ,030203 arthritis & rheumatology ,030222 orthopedics ,Viscosupplements ,Platelet-Rich Plasma ,business.industry ,Cartilage ,Graft Survival ,Osteochondral transplantation ,medicine.anatomical_structure ,chemistry ,Platelet-rich plasma ,Models, Animal ,Rabbits ,business ,Cartilage Diseases - Abstract
Introduction Autologous osteochondral transplantation (AOT) is a treatment for osteochondral lesions with known concerns, including histological degradation of the graft and poor cartilage integration. Platelet-rich plasma (PRP) and hyaluronic acid (HA) have been described has having the potential to improve results. The aim of this study was to evaluate the effect of PRP and HA on AOT in a rabbit model. Methods Thirty-six rabbits underwent bilateral knee AOT treated with either the biological adjunct (PRP, n = 12; HA, n = 12; PRP + HA, n = 12) or saline (control). PRP and HA were administered as an intra-articular injection. The rabbits were euthanized at 3, 6, or 12 weeks postoperatively. The graft sections were assessed using the modified International Cartilage Repair Society (ICRS) scoring system. The results from the PRP alone group is from previously published data. Results The mean modified ICRS histological score for the PRP-treated group was higher than its control ( P = 0.002). The mean modified ICRS histological score for the HA-treated group showed no difference compared with its control ( P = 0.142). The mean modified ICRS histological score for the PRP + HA–treated group was higher than its control ( P = 0.006). There was no difference between the mean modified ICRS scores of the PRP- and the PRP + HA–treated grafts ( P = 0.445). Conclusion PRP may decrease graft degradation and improve chondral integration in an animal model. In this model, the addition of HA was not synergistic for the parameters assessed. Level of Evidence. Basic science, Level V. Clinical Relevance. PRP can be used as an adjunct to AOT, which may decrease graft degeneration and improve clinical outcomes. HA may not influence AOT.
- Published
- 2017
43. Identification of the atypically modified autoantigen Ars2 as the target of B-cell receptors from activated B-cell-type diffuse large B-cell lymphoma
- Author
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Christina Körbel, Stephan Stilgenbauer, Michael Pfreundschuh, Rainer M. Bohle, Stefan Barth, Klaus-Dieter Preuss, Frank Neumann, Evi Regitz, Andreas Rosenwald, Lorenz Trümper, Anja Mottok, Maria Kemele, Viola Pöschel, Lorenz Thurner, Niels Murawski, Natalia Quiroga, Dominic Kaddu-Mulindwa, Sylvia Hartmann, Wolfram Klapper, Claudia Schormann, Boris Kubuschok, Michael D. Menger, Gerhard Held, Anna Nimmesgern, Martin-Leo Hansmann, Moritz Bewarder, Natalie Fadle, and Matthias W. Lascke
- Subjects
B-Lymphocytes ,Chemistry ,B-cell receptor ,breakpoint cluster region ,Germinal center ,Receptors, Antigen, B-Cell ,Hematology ,medicine.disease ,Autoantigens ,Article ,Lymphoma ,medicine.anatomical_structure ,Antigen ,immune system diseases ,hemic and lymphatic diseases ,Cancer research ,medicine ,Humans ,ddc:610 ,Lymphoma, Large B-Cell, Diffuse ,Receptor ,Diffuse large B-cell lymphoma ,B cell ,Signal Transduction - Abstract
It has been suggested that stimulation of B-cell receptors (BCR) by specific antigens plays a pathogenic role in diffuse large B-cell lymphoma (DLBCL). Here, it was the aim to screen for specific reactivities of DLBCL-BCR in the spectrum of autoantigens and antigens of infectious origin. Arsenite resistance protein 2 (Ars2) was identified as the BCR target of three of five activated B-cell type DLBCL cell lines and two of 11 primary DLBCL cases. Compared to controls, Ars2 was hypophosphorylated exclusively in cases and cell lines with Ars2-specific BCR. In a validation cohort, hypophosphorylated Ars2 was found in eight of 31 activated B-cell type DLBCL, but in only one of 20 germinal center B-cell like type DLBCL. Incubation with Ars2 induced BCR-pathway activation and increased proliferation, while an Ars2/ETA’ toxin conjugate induced killing of cell lines with Ars2-reactive BCR. Ars2 appears to play a role in a subgroup of activated B-cell-type DLBCL. Moreover, transformed DLBCL lines with Ars2-reactive BCR still showed growth advantage after incubation with Ars2. These results provide knowledge about the pathogenic role of a specific antigen stimulating the BCR pathway in DLCBL.
- Published
- 2019
44. Polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP) in blood plasma - Results of the German environmental survey for children and adolescents 2014-2017 (GerES V)
- Author
-
Nicole Bandow, Aline Murawski, Marike Kolossa-Gehring, George Sawal, and André Conrad
- Subjects
Male ,Adolescent ,Hexachlorocyclohexane ,010501 environmental sciences ,01 natural sciences ,West germany ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Age groups ,Environmental health ,Germany ,Blood plasma ,Hydrocarbons, Chlorinated ,Medicine ,Humans ,030212 general & internal medicine ,Pesticides ,Child ,0105 earth and related environmental sciences ,business.industry ,Public Health, Environmental and Occupational Health ,Organochlorine pesticide ,Hexachlorobenzene ,Environmental Exposure ,Fish consumption ,Polychlorinated Biphenyls ,chemistry ,Plasma concentration ,Environmental Pollutants ,Female ,business - Abstract
The German Environmental Survey for Children and Adolescents 2014–2017 (GerES V) investigated the current internal exposure to polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP). These analyses were carried out for a population-representative sub-sample of 1135 children and adolescents (aged 3–17 years) of all 2394 GerES V participants. Blood plasma samples were analyzed for seven indicator PCB (PCB 28, PCB 52, PCB 101, PCB 118, PCB 138, PCB 153 and PCB 180) and selected OCP (hexachlorobenzene, three hexachlorocyclohexane isomers, 4,4′-DDT, 4,4′-DDD and 4,4′-DDE). Despite risk mitigation measures and bans put into force some decades ago children and adolescents living in Germany are still exposed to PCB and OCP: Highest geometric mean plasma concentrations were measured for 4,4′-DDE (0.158 μg/L), followed by PCB 138 (0.049 μg/L), PCB 153 (0.066 μg/L) and PCB 180 (0.032 μg/L). Different application patterns of compounds between former East and former West Germany are still reflected by differences in plasma concentrations. Significant differences between age groups and by sexes were found. Moreover, the influence of breastfeeding and fish consumption, which was also found in other studies, was confirmed. Comparison with the results of GerES 2003–2006 confirms a decreasing trend in blood samples observed world-wide. Currently, health-based guidance values for PCB are still exceeded, though to a very limited extent. Also, the widespread occurrence of these compounds underlines the need for further monitoring of these compounds in humans although they are no longer marketed.
- Published
- 2019
45. Bio-Based Composites with Enhanced Matrix-Reinforcement Interactions from the Polymerization of α-Eleostearic Acid
- Author
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Amanda Murawski and Rafael L. Quirino
- Subjects
bio-based materials ,Materials science ,Double bond ,Radical polymerization ,Thermosetting polymer ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,fatty acids ,symbols.namesake ,tung oil ,Materials Chemistry ,Composite material ,chemistry.chemical_classification ,thermosets ,technology, industry, and agriculture ,cellulose composites ,Surfaces and Interfaces ,Polymer ,Adhesion ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Surfaces, Coatings and Films ,Vegetable oil ,Polymerization ,chemistry ,lcsh:TA1-2040 ,symbols ,0210 nano-technology ,Raman spectroscopy ,lcsh:Engineering (General). Civil engineering (General) - Abstract
Vegetable oil-based composites have been proposed as interesting bio-based materials in the recent past. The carbon&ndash, carbon double bonds in unsaturated vegetable oils are ideal reactive sites for free radical polymerization. Without the presence of a reinforcement, typical vegetable oil-based polymers cannot achieve competitive thermo-mechanical properties. Compatibilizers have been utilized to enhance the adhesion between resin and reinforcement. This work discusses the antagonist implications of polarity and crosslink density of an unprecedented polar &alpha, eleostearic acid-based resin reinforced with &alpha, cellulose, eliminating the need of a compatibilizer. It is shown that the polar regions of &alpha, eleostearic acid can interact directly with the polar reinforcement. The successful isolation of &alpha, eleostearic acid from tung oil was verified via GC-MS, 1H NMR, Raman, and FT-IR spectroscopies. The optimal cure schedule for the resin was determined by DSC and DEA. The composites&rsquo, thermo-mechanical properties were assessed by TGA, DSC, and DMA.
- Published
- 2019
46. Decreased gas-diffusion electrode porosity due to increased electrocatalyst loading leads to diffusional limitations in cathodic H2O2 electrosynthesis
- Author
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Emily Murawski, Negin Kananizadeh, Spencer Lindsay, Sudeep C. Popat, and Apparao M. Rao
- Subjects
Materials science ,Gas diffusion electrode ,Renewable Energy, Sustainability and the Environment ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,Carbon black ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrosynthesis ,Electrochemistry ,Electrocatalyst ,01 natural sciences ,0104 chemical sciences ,Cathodic protection ,Chemical engineering ,chemistry ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,0210 nano-technology ,Carbon ,Faraday efficiency - Abstract
The effect of carbon black electrocatalyst loading on the efficiency of cathodic hydrogen peroxide (H2O2) electrosynthesis in neutral buffered catholytes using gas-diffusion electrodes (GDEs) was evaluated. Increased carbon black loadings on carbon cloth-based GDEs (from 0.5 to 1.5 mg/cm2 to 3.3 mg/cm2) reduced the cathodic coulombic efficiency significantly although no significant advantage in terms of electrochemical performance was noted for the highest loading studied in linear sweep voltammograms. Decreasing cathodic coulombic efficiency during a given batch H2O2 electrosynthesis experiment was a result of increasing catholyte pH, which occurred irrespective of the carbon black loading, and could be alleviated using a higher buffer concentration. Scanning electron microscopy (SEM) and X-ray computed tomography (CT) reconstructions of the GDEs with the different carbon black loadings showed that increased loading leads to lower GDE porosity, which likely causes mass transport limitations, that result in consumption of H2O2 in-situ in the electrocatalyst layer, either due to electrochemical reduction or decomposition in high pH conditions. Future studies should focus on engineering GDE structures that allow enhanced mass transport rates for H2O2 out of the GDE, thus also achieving high coulombic efficiencies.
- Published
- 2021
47. Small Molecule Solar Cells
- Author
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Vasileios C. Nikolis, Jan Murawski, Karl Leo, Caroline Murawski, Tobias Moench, Koen Vandewal, and Christian Koerner
- Subjects
chemistry.chemical_classification ,Materials science ,Organic solar cell ,Doping ,Nanotechnology ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Small molecule ,0104 chemical sciences ,law.invention ,Organic semiconductor ,Vacuum sublimation ,chemistry ,Cascade ,law ,Solar cell ,0210 nano-technology - Abstract
In the last years, organic photovoltaics have moved from a lab curiosity to a commercially viable technology. In this chapter, we consider organic photovoltaics based on oligomers (“small molecules”) which are deposited by vacuum sublimation. While the physics of the small molecule materials is in many ways very similar to those of polymer organic materials, there are significant differences in materials synthesis, processing, and device concepts. We review a few classes of small molecule solar cell materials and discuss their properties in devices. We discuss device concepts for small molecule organic solar cells, in particular pin devices based on doped transport layers and cascade designs. We point out the points where devices can be improved and describe paths to higher efficiencies, including multi-junction devices which can be very well realized with small molecule organic semiconductors.
- Published
- 2017
48. Influence of Methyl Substituents on Azo-Dye Photoalignment in Thin Films
- Author
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V. S. Mikulich, Al. A. Muravsky, Vladimir Agabekov, and An. A. Murawski
- Subjects
Materials science ,Plane (geometry) ,Potassium ,Substituent ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Photochemistry ,01 natural sciences ,010309 optics ,chemistry.chemical_compound ,chemistry ,0103 physical sciences ,Structural isomer ,Molecule ,Irradiation ,Thin film ,0210 nano-technology ,Layer (electronics) ,Spectroscopy - Abstract
Photoalignment of azo dyes derived from salicylic acid in thin films (80–200 nm) was studied upon irradiation with polarized light (λmax = 457 nm). It is shown that different trends of molecular reorientation, i.e., in the layer plane or orthogonal to it, are observed depending on the position of the methyl substituent in the dye structure. A new distribution parameter Z that allows the portion of molecules reoriented in the layer plane during exposure to be determined is introduced. The novel azo dye potassium 3,7-bis[1-(4-hydroxy-3-carboxylate)phenylazo]-5,5′-dioxodibenzothiophene was synthesized. Its molecules are photoaligned in the layer plane upon irradiation with polarized light.
- Published
- 2016
49. Tracking the <scp> H </scp> ercules 265 marine gas well blowout in the <scp>G</scp> ulf of <scp>M</scp> exico
- Author
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Bryan J. O'Malley, Tamay M. Özgökmen, Isabel C. Romero, Shuyi S. Chen, Patrick Schwing, María J. Olascoaga, Francisco J. Beron-Vera, Dana L. Wetzel, Steven A. Murawski, Susan M. Snyder, David J. Hollander, Ping Zhu, and Edward H. Ryan
- Subjects
chemistry.chemical_classification ,Pollution ,010504 meteorology & atmospheric sciences ,biology ,media_common.quotation_subject ,Sediment ,Polycyclic aromatic hydrocarbon ,010501 environmental sciences ,Oceanography ,biology.organism_classification ,01 natural sciences ,Demersal zone ,Plume ,Foraminifera ,Drifter ,Geophysics ,chemistry ,Space and Planetary Science ,Geochemistry and Petrology ,Indicator species ,Earth and Planetary Sciences (miscellaneous) ,Environmental science ,0105 earth and related environmental sciences ,media_common - Abstract
On 23 July 2013, a marine gas rig (Hercules 265) ignited in the northern Gulf of Mexico. The rig burned out of control for 2 days before being extinguished. We conducted a rapid-response sampling campaign near Hercules 265 after the fire to ascertain if sediments and fishes were polluted above earlier baseline levels. A surface drifter study confirmed that surface ocean water flowed to the southeast of the Hercules site, while the atmospheric plume generated by the blowout was in eastward direction. Sediment cores were collected to the SE of the rig at a distance of ∼0.2, 8, and 18 km using a multicorer, and demersal fishes were collected from ∼0.2 to 8 km SE of the rig using a longline (508 hooks). Recently deposited sediments document that only high molecular weight (HMW) polycyclic aromatic hydrocarbon (PAH) concentrations decreased with increasing distance from the rig suggesting higher pyrogenic inputs associated with the blowout. A similar trend was observed in the foraminifera Haynesina germanica, an indicator species of pollution. In red snapper bile, only HMW PAH metabolites increased in 2013 nearly double those from 2012. Both surface sediments and fish bile analyses suggest that, in the aftermath of the blowout, increased concentration of pyrogenically derived hydrocarbons was transported and deposited in the environment. This study further emphasizes the need for an ocean observing system and coordinated rapid-response efforts from an array of scientific disciplines to effectively assess environmental impacts resulting from accidental releases of oil contaminants.
- Published
- 2016
50. Metabolites of the fragrance 2-(4-tert-butylbenzyl)propionaldehyde (lysmeral) in urine of children and adolescents in Germany – Human biomonitoring results of the German Environmental Survey 2014–2017 (GerES V)
- Author
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Markus Stoeckelhuber, Maria I.H. Schmied-Tobies, Enrico Rucic, Max Scherer, Gerda Schwedler, Aline Murawski, Nina Fiedler, Marike Kolossa-Gehring, Gerhard Scherer, and Nikola Pluym
- Subjects
Male ,Adolescent ,Metabolite ,media_common.quotation_subject ,Urine ,010501 environmental sciences ,01 natural sciences ,Cosmetics ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Germany ,Biomonitoring ,Humans ,Medicine ,BUTYLPHENYL METHYLPROPIONAL ,030212 general & internal medicine ,Food science ,Child ,0105 earth and related environmental sciences ,media_common ,Aldehydes ,business.industry ,Public Health, Environmental and Occupational Health ,Propionaldehyde ,Health Surveys ,Perfume ,chemistry ,Endocrine disruptor ,Child, Preschool ,Female ,business ,Lilial ,Biological Monitoring - Abstract
The synthetic fragrance 2-(4-tert-butylbenzyl)propionaldehyde, also known as lysmeral, butylphenyl methylpropional, lilial, or lily aldehyde, is widely used in cosmetics, personal care products, laundry detergents, and air fresheners. It is classified as suspected to be harmful to fertility and possibly endocrine disrupting. Its maximum concentration in cosmetics is limited. First-morning void urine samples (N = 2133) were analysed for several metabolites of lysmeral (Chemical Abstract Service (CAS) No.: 80-54-6). Samples were collected in the population-representative German Environmental Survey for Children and Adolescents 2014–2017 (GerES V) from German residents aged 3–17 years. Four main metabolites tert-butylbenzoic acid, lysmerol, lysmerylic acid, and hydroxy-lysmerylic acid were found in quantifiable amounts in 100%, 99%, 40%, and 23% of the samples, respectively, with geometric mean concentrations of 10.21 μg/L (8.658 μg/gcrea) for tert-butylbenzoic acid, 1.528 μg/L (1.296 μg/gcrea) for lysmerol, and below the limit of quantification of 0.2 μg/L and 0.4 μg/L for lysmerylic acid and hydroxy-lysmerylic acid, respectively. Girls had higher urinary concentrations of lysmeral metabolites than boys. Usage of fragrances, fabric softener, and personal care products, especially perfume, was positively associated with urinary concentrations of lysmeral metabolites. Source identification builds a basis to derive proposals for reduction of exposure. These results can also provide the foundation for developing reference values for urinary metabolite concentrations of lysmeral in children and adolescents in Germany that will facilitate recognising future exposure trends.
- Published
- 2020
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