719 results on '"Zajdel, P."'
Search Results
2. Bubbles enable volumetric negative compressibility in metastable elastocapillary systems
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Caprini, Davide, Battista, Francesco, Zajdel, Pawel, Di Muccio, Giovanni, Guardiani, Carlo, Trump, Benjamin, Carter, Marcus, Yakovenko, Andrey A., Amayuelas, Eder, Bartolomé, Luis, Meloni, Simone, Grosu, Yaroslav, Casciola, Carlo Massimo, and Giacomello, Alberto
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Condensed Matter - Soft Condensed Matter - Abstract
Although coveted in applications, few materials expand when subject to compression or contract under decompression, i.e., exhibit the negative compressibility phenomenon. A key step to achieve such counterintuitive behaviour is the destabilisations of (meta)stable equilibria of the constituents. Here, we propose a simple strategy to obtain negative compressibility exploiting capillary forces both to precompress the elastic material and to release such precompression by a threshold phenomenon -- the reversible formation of a bubble in a lyophobic flexible cavity. We demonstrate that the solid part of such metastable elastocapillary systems displays negative compressibility across different scales: hydrophobic microporous materials, proteins, and millimetre-sized laminae. This concept is applicable to fields such as porous materials, biomolecules, sensors and may be easily extended to create unexpected material susceptibilities.
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- 2023
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3. Satellite laser ranging to BeiDou-3 satellites: initial performance and contribution to orbit model improvement
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Zajdel, Radosław, Nowak, Adrian, and Sośnica, Krzysztof
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- 2024
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4. Mellitic Acid-Supported Synthesis of Anisotropic Nanoparticles Used as SERS Substrate
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Beata Wrzosek, Karolina Zajdel, Paulina Jeleń, and Jolanta Bukowska
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Chemistry ,QD1-999 - Published
- 2024
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5. Bubbles enable volumetric negative compressibility in metastable elastocapillary systems
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Davide Caprini, Francesco Battista, Paweł Zajdel, Giovanni Di Muccio, Carlo Guardiani, Benjamin Trump, Marcus Carter, Andrey A. Yakovenko, Eder Amayuelas, Luis Bartolomé, Simone Meloni, Yaroslav Grosu, Carlo Massimo Casciola, and Alberto Giacomello
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Science - Abstract
Abstract Although coveted in applications, few materials expand when subject to compression or contract under decompression, i.e., exhibit negative compressibility. A key step to achieve such counterintuitive behaviour is the destabilisations of (meta)stable equilibria of the constituents. Here, we propose a simple strategy to obtain negative compressibility exploiting capillary forces both to precompress the elastic material and to release such precompression by a threshold phenomenon – the reversible formation of a bubble in a hydrophobic flexible cavity. We demonstrate that the solid part of such metastable elastocapillary systems displays negative compressibility across different scales: hydrophobic microporous materials, proteins, and millimetre-sized laminae. This concept is applicable to fields such as porous materials, biomolecules, sensors and may be easily extended to create unexpected material susceptibilities.
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- 2024
- Full Text
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6. GENESIS: Co-location of Geodetic Techniques in Space
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Delva, Pacôme, Altamimi, Zuheir, Blazquez, Alejandro, Blossfeld, Mathis, Böhm, Johannes, Bonnefond, Pascal, Boy, Jean-Paul, Bruinsma, Sean, Bury, Grzegorz, Chatzinikos, Miltiadis, Couhert, Alexandre, Courde, Clément, Dach, Rolf, Dehant, Véronique, Dell'Agnello, Simone, Elgered, Gunnar, Enderle, Werner, Exertier, Pierre, Glaser, Susanne, Haas, Rüdiger, Huang, Wen, Hugentobler, Urs, Jäggi, Adrian, Karatekin, Ozgur, Lemoine, Frank G., Poncin-Lafitte, Christophe Le, Lunz, Susanne, Männel, Benjamin, Mercier, Flavien, Métivier, Laurent, Meyssignac, Benoît, Müller, Jürgen, Nothnagel, Axel, Perosanz, Felix, Rietbroek, Roelof, Rothacher, Markus, Sert, Hakan, Sosnica, Krzysztof, Testani, Paride, Ventura-Traveset, Javier, Wautelet, Gilles, and Zajdel, Radoslaw
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Physics - Instrumentation and Detectors ,Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Physics - Atmospheric and Oceanic Physics ,Physics - Applied Physics ,Physics - Geophysics - Abstract
Improving and homogenizing time and space reference systems on Earth and, more directly, realizing the Terrestrial Reference Frame (TRF) with an accuracy of 1mm and a long-term stability of 0.1mm/year are relevant for many scientific and societal endeavors. The knowledge of the TRF is fundamental for Earth and navigation sciences. For instance, quantifying sea level change strongly depends on an accurate determination of the geocenter motion but also of the positions of continental and island reference stations, as well as the ground stations of tracking networks. Also, numerous applications in geophysics require absolute millimeter precision from the reference frame, as for example monitoring tectonic motion or crustal deformation for predicting natural hazards. The TRF accuracy to be achieved represents the consensus of various authorities which has enunciated geodesy requirements for Earth sciences. Today we are still far from these ambitious accuracy and stability goals for the realization of the TRF. However, a combination and co-location of all four space geodetic techniques on one satellite platform can significantly contribute to achieving these goals. This is the purpose of the GENESIS mission, proposed as a component of the FutureNAV program of the European Space Agency. The GENESIS platform will be a dynamic space geodetic observatory carrying all the geodetic instruments referenced to one another through carefully calibrated space ties. The co-location of the techniques in space will solve the inconsistencies and biases between the different geodetic techniques in order to reach the TRF accuracy and stability goals endorsed by the various international authorities and the scientific community. The purpose of this white paper is to review the state-of-the-art and explain the benefits of the GENESIS mission in Earth sciences, navigation sciences and metrology., Comment: 31 pages, 9 figures, submitted to Earth, Planets and Space (EPS)
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- 2022
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7. Open Source Software: An Approach to Controlling Usage and Risk in Application Ecosystems
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Zajdel, Stan, Costa, Diego Elias, and Mili, Hafedh
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Computer Science - Software Engineering - Abstract
The Open Source Software movement has been growing exponentially for a number of years with no signs of slowing. Driving this growth is the widespread availability of libraries and frameworks that provide many functionalities. Developers are saving time and money incorporating this functionality into their applications resulting in faster more feature-rich releases. Despite the growing success and the advantages that open source software provides, there is a dark side. Due to its community construction and largely unregulated distribution, the majority of open source software contains bugs, vulnerabilities and other issues making it highly susceptible to exploits. The lack of oversight, in general, hinders the quality of this software resulting in a trickle-down effect in the applications that use it. Additionally, developers who use open source tend to arbitrarily download the software into their build systems but rarely keep track of what they have downloaded resulting in an excessive amount of open source software in their applications and in their ecosystem. This paper discusses processes and practices that users of open source software can implement into their environments that can safely track and control the introduction and usage of open source software into their applications, and report on some preliminary results obtained in an industrial context. We conclude by discussing governance issues related to the disciplined use and reuse of open source and areas for further improvements.
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- 2022
8. Synchronous recording of magnetocardiographic and electrocardiographic signals
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Kazimierz Pȩczalski, Judyta Sobiech, Teodor Buchner, Thomas Kornack, Elizabeth Foley, Daniel Janczak, Małgorzata Jakubowska, David Newby, Nancy Ford, and Maryla Zajdel
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Medicine ,Science - Abstract
Abstract We present a system for simultaneous recording of the electrocardiogram and the magnetocardiogram. The measurement system contained of printed carbon electrodes and SERF magnetometer. The use of this system confirms that the position of the end of the magnetic T wave extends further than the electric T wave, which is an important indicator for the diagnosis of cardiological patients and for drug arrhythmogenicity. We analyze this phenomenon in depth, and demonstrate, that it originates from the fundamental difference between electric and magnetic measurements. The measured value is always bipolar since the electric measurements require two electrodes. We demonstrate how the dual electric and magnetic measuring system adds a new information to the commonly used electrocardiographic diagnosis. The ECG should be interpreted as the spatial asymmetry of the electric cardiac potential, and not as the potential itself. The results seem to prove, that the relation between the magnetic and the electric imaging of neural activities may be broadly applied for the benefit of medical diagnosis in cardiology and many other fields, where the neural activity is measured. This is a pilot study which requires further confirmation at the clinical level.
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- 2024
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9. Genus Sambucus: Exploring Its Potential as a Functional Food Ingredient with Neuroprotective Properties Mediated by Antioxidant and Anti-Inflammatory Mechanisms
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Anna Merecz-Sadowska, Przemysław Sitarek, Karolina Zajdel, Wiktoria Sztandera, and Radosław Zajdel
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Sambucus nigra ,elderberry ,neuroprotection ,cognitive function ,oxidative stress ,neuroinflammation ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The genus Sambucus, mainly Sambucus nigra, has emerged as a valuable source of bioactive compounds with potential neuroprotective properties. This review explores the antioxidant, anti-inflammatory, and neuroregenerative effects of Sambucus-derived compounds and their implications for brain health and cognitive function. In vitro studies have demonstrated the ability of Sambucus extracts to mitigate oxidative stress, modulate inflammatory responses, and promote neural stem cell proliferation and differentiation. In vivo studies using animal models of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s, have shown that Sambucus compounds can improve cognitive function, motor performance, and neuronal survival while attenuating neuroinflammation and oxidative damage. The neuroprotective effects of Sambucus are primarily attributed to its rich content of polyphenols, particularly anthocyanins, which exert their benefits through multiple mechanisms, including the modulation of signaling pathways involved in inflammation, apoptosis, mitochondrial function, and oxidative stress. Furthermore, the potential of Sambucus as a functional food ingredient is discussed, highlighting its application in various food products and the challenges associated with the stability and bioavailability of its bioactive compounds. This review provides a comprehensive overview of the current state of research on the neuroprotective potential of Sambucus and its derivatives, offering valuable insights for the development of dietary strategies to promote brain health and prevent age-related cognitive decline.
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- 2024
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10. Finite velocity of ECG signal propagation: preliminary theory, results of a pilot experiment and consequences for medical diagnosis
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Buchner, Teodor, Zajdel, Maryla, Pȩczalski, Kazimierz, and Nowak, Paweł
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- 2023
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11. GENESIS: co-location of geodetic techniques in space
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Delva, Pacôme, Altamimi, Zuheir, Blazquez, Alejandro, Blossfeld, Mathis, Böhm, Johannes, Bonnefond, Pascal, Boy, Jean-Paul, Bruinsma, Sean, Bury, Grzegorz, Chatzinikos, Miltiadis, Couhert, Alexandre, Courde, Clément, Dach, Rolf, Dehant, Véronique, Dell’Agnello, Simone, Elgered, Gunnar, Enderle, Werner, Exertier, Pierre, Glaser, Susanne, Haas, Rüdiger, Huang, Wen, Hugentobler, Urs, Jäggi, Adrian, Karatekin, Ozgur, Lemoine, Frank G., Le Poncin-Lafitte, Christophe, Lunz, Susanne, Männel, Benjamin, Mercier, Flavien, Métivier, Laurent, Meyssignac, Benoît, Müller, Jürgen, Nothnagel, Axel, Perosanz, Felix, Rietbroek, Roelof, Rothacher, Markus, Schuh, Harald, Sert, Hakan, Sosnica, Krzysztof, Testani, Paride, Ventura-Traveset, Javier, Wautelet, Gilles, and Zajdel, Radoslaw
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- 2023
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12. Biologiczne uwarunkowania modyfikacji wymowy polskich sybilantów dziąsłowo-palatalnych przez młodych dorosłych
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Beata Ciecierska-Zajdel
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polskie sybilanty dziąsłowo-palatalne ,zróżnicowanie wymowy ,zaburzenia artykulacji ,zmiany fonetycznie w języku polskim ,uwarunkowania wymowy ,Philology. Linguistics ,P1-1091 - Abstract
Autorka badała uwarunkowania biologiczne tendencji do modyfikowania palatalności sybilantów [ɕ], [ʑ], [t͡ɕ], [d͡ʑ] przez młodych dorosłych. Badaną grupę stanowiło 30 studentów, prezentujących różny stopień prawidłowości realizacji wymienionych spółgłosek. Byli oni poddani badaniu logopedycznemu oceniającemu ich warunki anatomiczne, funkcjonowanie aparatu artykulacyjnego, prawidłowość przebiegu czynności prymarnych, uwarunkowania percepcyjne oraz prawidłowość wymowy pozostałych głosek języka polskiego. Badanie miało charakter ilościowy. Punktowe wyniki badania zostały zestawione z liczbą nienormatywnie realizowanych sybilantów i poddane analizie statystycznej. Okazało się, że istnieje wyraźna zależność między czynnikami anatomiczno-funkcjonalnymi a liczbą zmodyfikowanych spółgłosek [ɕ], [ʑ], [t͡ɕ], [d͡ʑ], więc zniekształcania palatalności sybilantów nie można traktować jedynie jako uwarunkowanej społecznie lub kulturowo maniery wymowy.
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- 2024
13. Activation of GFRAL+ neurons induces hypothermia and glucoregulatory responses associated with nausea and torpor
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Linda Engström Ruud, Ferran Font-Gironès, Joanna Zajdel, Lara Kern, Júlia Teixidor-Deulofeu, Louise Mannerås-Holm, Alba Carreras, Barbara Becattini, Andreas Björefeldt, Eric Hanse, Henning Fenselau, Giovanni Solinas, Jens C. Brüning, Thomas F. Wunderlich, Fredrik Bäckhed, and Johan Ruud
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CP: Metabolism ,CP: Neuroscience ,Biology (General) ,QH301-705.5 - Abstract
Summary: GFRAL-expressing neurons actuate aversion and nausea, are targets for obesity treatment, and may mediate metformin effects by long-term GDF15-GFRAL agonism. Whether GFRAL+ neurons acutely regulate glucose and energy homeostasis is, however, underexplored. Here, we report that cell-specific activation of GFRAL+ neurons using a variety of techniques causes a torpor-like state, including hypothermia, the release of stress hormones, a shift from glucose to lipid oxidation, and impaired insulin sensitivity, glucose tolerance, and skeletal muscle glucose uptake but augmented glucose uptake in visceral fat. Metabolomic analysis of blood and transcriptomics of muscle and fat indicate alterations in ketogenesis, insulin signaling, adipose tissue differentiation and mitogenesis, and energy fluxes. Our findings indicate that acute GFRAL+ neuron activation induces endocrine and gluco- and thermoregulatory responses associated with nausea and torpor. While chronic activation of GFRAL signaling promotes weight loss in obesity, these results show that acute activation of GFRAL+ neurons causes hypothermia and hyperglycemia.
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- 2024
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14. MoO3/MeMoO4 (Me = Cu, Ni, Co, Fe, Mn, and Cr) composites as materials for prospective optical and electrical applications
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Talik, E., Guzik, A., Molak, A., Zajdel, P., Trump, B., and Yakovenko, A.A.
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- 2024
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15. Interactions between dietary omega-3 polyunsaturated fatty acids and the gut microbiota
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Alicja Zajdel and Adam Wilczok
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gut microbiota ,omega-3 pufas ,gut microbiota - pufas omega-3 interactions ,health ,Pharmacy and materia medica ,RS1-441 - Abstract
The gut microbiota forms a complex and metabolically active ecosystem. Changes in gut microbiota activity correlate with the health status.. It is not known whether the dysfunction of the intestinal microbiota due to undesirable changes in the qualitative and quantitative composition (so-called dysbiosis) is a cause or effect of disease states. Long-term dietary habits play a key role in the formation of the human-specific gut microbiota. Despite many publications on the effects of carbohydrates with prebiotic properties, the effects of dietary fats, such as omega-3 polyunsaturated fatty acids (PUFAs), on the gut microbiota are not fully explained. The main bioactive forms in humans among omega-3 PUFAs, are eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6). These compounds play an important role in the proper functioning of the human body, as well as in the prevention and treatment of many diseases, so they are widely used as nutraceuticals. Few studies with adults have shown changes in gut microbiota after omega-3 PUFAs supplementation and a reduction in dysbiosis. Omega-3 PUFAs can influence the diversity and abundance of the gut microbiome, on the other hand, gut microbes can affect the metabolism and absorption of these compounds. Omega-3 PUFAs affect the gut microbiome in three main ways: by modulating the type and abundance of intestinal microbes, by altering the levels of proinflammatory mediators such as endotoxins (lipopolysaccharides) and interleukine 17; and by regulating the levels of short-chain fatty acids (SCFAs). The aim of this study was to summarize the current state of knowledge on the biological activity of the intestinal microbiota, particularly the interactions of the microbiota and omega-3 polyunsaturated fatty acids in humans. The data search was performed in July 2023 in the PubMed database and publicly available literature using the following queries: "intestinal microbiota", "microbiome", "omega-3 polyunsaturated acids intestinal microbiota", "EPA intestinal microbiota", "DHA intestinal microbiota". The article discusses the interactions between the intestinal microbiota and omega-3 PUFAs. The issues presented allow to conclude that elucidating the mechanisms of interaction between the gut microbiota and omega-3 PUFAs, may provide the basis for developing more effective therapeutic strategies.
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- 2023
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16. Machine Learning for Mechanical Ventilation Control (Extended Abstract)
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Suo, Daniel, Agarwal, Naman, Xia, Wenhan, Chen, Xinyi, Ghai, Udaya, Yu, Alexander, Gradu, Paula, Singh, Karan, Zhang, Cyril, Minasyan, Edgar, LaChance, Julienne, Zajdel, Tom, Schottdorf, Manuel, Cohen, Daniel, and Hazan, Elad
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Computer Science - Machine Learning - Abstract
Mechanical ventilation is one of the most widely used therapies in the ICU. However, despite broad application from anaesthesia to COVID-related life support, many injurious challenges remain. We frame these as a control problem: ventilators must let air in and out of the patient's lungs according to a prescribed trajectory of airway pressure. Industry-standard controllers, based on the PID method, are neither optimal nor robust. Our data-driven approach learns to control an invasive ventilator by training on a simulator itself trained on data collected from the ventilator. This method outperforms popular reinforcement learning algorithms and even controls the physical ventilator more accurately and robustly than PID. These results underscore how effective data-driven methodologies can be for invasive ventilation and suggest that more general forms of ventilation (e.g., non-invasive, adaptive) may also be amenable., Comment: Machine Learning for Health (ML4H) at NeurIPS 2021 - Extended Abstract. arXiv admin note: substantial text overlap with arXiv:2102.06779
- Published
- 2021
17. Exploring the Anticancer Potential of Semisynthetic Derivatives of 7α-Acetoxy-6β-hydroxyroyleanone from Plectranthus sp.: An In Silico Approach
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Anna Merecz-Sadowska, Vera M. S. Isca, Przemysław Sitarek, Tomasz Kowalczyk, Magdalena Małecka, Karolina Zajdel, Hanna Zielińska-Bliźniewska, Mariusz Jęcek, Patricia Rijo, and Radosław Zajdel
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7α-acetoxy-6β-hydroxyroyleanone ,Plectranthus grandidentatus ,anticancer activity ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The diterpene 7α-acetoxy-6β-hydroxyroyleanone isolated from Plectranthus grandidentatus demonstrates promising antibacterial, anti-inflammatory and anticancer properties. However, its bioactivity may be enhanced via strategic structural modifications of such natural products through semisynthesis. The anticancer potential of 7α-acetoxy-6β-hydroxyroyleanone and five derivatives was analyzed in silico via the prediction of chemicals absorption, distribution, metabolism, excretion, and toxicity (ADMET), quantum mechanical calculations, molecular docking and molecular dynamic simulation. The protein targets included regulators of apoptosis and cell proliferation. Additionally, network pharmacology was used to identify potential targets and signaling pathways. Derivatives 7α-acetoxy-6β-hydroxy-12-O-(2-fluoryl)royleanone and 7α-acetoxy-6β-(4-fluoro)benzoxy-12-O-(4-fluoro)benzoylroyleanone achieved high predicted binding affinities towards their respective protein panels, with stable molecular dynamics trajectories. Both compounds demonstrated favorable ADMET parameters and toxicity profiles. Their stability and reactivity were confirmed via geometry optimization. Network analysis revealed their involvement in cancer-related pathways. Our findings justify the inclusion of 7α-acetoxy-6β-hydroxy-12-O-(2-fluoryl)royleanone and 7α-acetoxy-6β-(4-fluoro)benzoxy-12-O-(4-fluoro)benzoylroyleanone in in vitro analyses as prospective anticancer agents. Our binding mode analysis and stability simulations indicate their potential as selective inhibitors. The data will guide studies into their structure optimization, enhancing efficacy and drug-likeness.
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- 2024
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18. Combination and SLR validation of IGS Repro3 orbits for ITRF2020
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Zajdel, Radosław, Masoumi, Salim, Sośnica, Krzysztof, Gałdyn, Filip, Strugarek, Dariusz, and Bury, Grzegorz
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- 2023
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19. Polish thread in the election campaign in Spain
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Jakub Zajdel
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Spain ,elections ,European Union ,Political science ,Social Sciences - Abstract
On 23 July 2023, parliamentary elections were held in Spain. It was one of the most important political events in Europe this year. For Polish observers, it could have been even more interesting because there was a Polish thread. The elections were won by the People's Party (PP/EPP), Neither can the Socialists (PSOE) consider themselves total losers. The biggest loser is the right-wing populist party Vox, which, despite very optimistic polls, lost around half of its seats.
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- 2023
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20. Effects of natural leaching on electronic properties of common lithium manganese oxide LiMn2O4
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Szubka, M., Talik, E., Bagińska, M., Wojdyła, M., Żebrowska, K., Pilch, M., Oboz, M., Maximenko, A., Paul, R., Hudson, M., and Zajdel, P.
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- 2024
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21. Structure and magnetism of AlCoCrCuFeNi high-entropy alloy
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Oboz, M., Zajdel, P., Zubko, M., Świec, P., Szubka, M., Kądziołka-Gaweł, M., Maximenko, A., Trump, B.A., and Yakovenko, A.A.
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- 2024
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22. Machine Learning for Mechanical Ventilation Control
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Suo, Daniel, Agarwal, Naman, Xia, Wenhan, Chen, Xinyi, Ghai, Udaya, Yu, Alexander, Gradu, Paula, Singh, Karan, Zhang, Cyril, Minasyan, Edgar, LaChance, Julienne, Zajdel, Tom, Schottdorf, Manuel, Cohen, Daniel, and Hazan, Elad
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Computer Science - Machine Learning - Abstract
We consider the problem of controlling an invasive mechanical ventilator for pressure-controlled ventilation: a controller must let air in and out of a sedated patient's lungs according to a trajectory of airway pressures specified by a clinician. Hand-tuned PID controllers and similar variants have comprised the industry standard for decades, yet can behave poorly by over- or under-shooting their target or oscillating rapidly. We consider a data-driven machine learning approach: First, we train a simulator based on data we collect from an artificial lung. Then, we train deep neural network controllers on these simulators.We show that our controllers are able to track target pressure waveforms significantly better than PID controllers. We further show that a learned controller generalizes across lungs with varying characteristics much more readily than PID controllers do.
- Published
- 2021
23. Anticancer Effects of Abietane Diterpene 7α-Acetoxy-6β-hydroxyroyleanone from Plectranthus grandidentatus and Its Semi-Synthetic Analogs: An In Silico Computational Approach
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Vera M. S. Isca, Przemysław Sitarek, Anna Merecz-Sadowska, Magdalena Małecka, Monika Owczarek, Joanna Wieczfińska, Radosław Zajdel, Paweł Nowak, Patricia Rijo, and Tomasz Kowalczyk
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7α-acetoxy-6β-hydroxyroyleanone ,Plectranthus grandidentatus ,anticancer activity ,Organic chemistry ,QD241-441 - Abstract
The abietane diterpenoid 7α-acetoxy-6β-hydroxyroyleanone (Roy) isolated from Plectranthus grandidentatus demonstrates cytotoxicity across numerous cancer cell lines. To potentiate anticancer attributes, a series of semi-synthetic Roy derivatives were generated and examined computationally. ADMET predictions were used to evaluate drug-likeness and toxicity risks. The antineoplastic potential was quantified by PASS. The DFT models were used to assess their reactivity and stability. Molecular docking determined cancer-related protein binding. MS simulations examined ligand–protein stability. Additionally, network pharmacology was used to identify potential targets and signaling pathways. Favorable ADME attributes and acceptable toxicity profiles were determined for all compounds. Strong anticancer potential was shown across derivatives (Pa 0.819–0.879). Strategic modifications altered HOMO–LUMO gaps (3.39–3.79 eV) and global reactivity indices. Favorable binding was revealed against cyclin-dependent kinases, BCL-2, caspases, receptor tyrosine kinases, and p53. The ligand exhibited a stable binding pose in MD simulations. Network analysis revealed involvement in cancer-related pathways. In silico evaluations predicted Roy and derivatives as effective molecules with anticancer properties. Experimental progress is warranted to realize their chemotherapeutic potential.
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- 2024
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24. Comparison of Flight Parameters in SIL Simulation Using Commercial Autopilots and X-Plane Simulator for Multi-Rotor Models
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Michal Welcer, Nezar Sahbon, and Albert Zajdel
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UAV ,autopilot ,SIL ,flight simulation ,control ,multi-rotor models ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
Modern aviation technology development heavily relies on computer simulations. SIL (Software-In-The-Loop) simulations are essential for evaluating autopilots and control algorithms for multi-rotors, including drones and other UAVs (Unmanned Aerial Vehicle). In such simulations, it is possible to compare the flight parameters achieved by flying platforms using various commercial autopilots widely used in the UAV sector. This research aims to provide objective and comprehensive insights into the effectiveness of different autopilot systems This article examines the simulated flight test results of a drone performing the same mission using different autopilot systems. The X-Plane software was used as an environment to simulate the dynamics of the drone and its surroundings. Matlab/Simulink r2023a provided the interface between autopilot software and X-Plane models. Those methods allowed us to obtain an appropriate comparison of the autopilot systems and indicate the main differences between them. This research focused on analyzing UAV flight characteristics such as stability, trajectory tracking, response time to control changes, and the overall effectiveness of autopilots. Various flight scenarios including take-off, landing, flight at a constant altitude, dynamic manoeuvrers and, flight along a planned trajectory were also examined. In order to obtain the most accurate and realistic results, the tests were carried out in various weather conditions. The aim of this research is to provide objective data and analysis to compare the performance of commercial autopilots. This method offers several advantages, including cost-effective testing, the ability to test in diverse environmental conditions, and the evaluation of autopilot algorithms without the need for real hardware. The findings of this study may have a considerable impact on how autopilot designers and developers choose the best platforms and technologies for their projects. Future research on this topic will compare the obtained data with flight test data.
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- 2024
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25. Prognostic Value of Metastatic Lymph Node Ratio and Identification of Factors Influencing the Lymph Node Yield in Patients Undergoing Curative Colon Cancer Resection
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Paweł Mroczkowski, Samuel Kim, Ronny Otto, Hans Lippert, Radosław Zajdel, Karolina Zajdel, and Anna Merecz-Sadowska
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colon cancer ,lymph nodes ,lymph node yield ,lymph node ratio ,five-year overall survival ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Due to the impact of nodal metastasis on colon cancer prognosis, adequate regional lymph node resection and accurate pathological evaluation are required. The ratio of metastatic to examined nodes may bring an additional prognostic value to the actual staging system. This study analyzes the identification of factors influencing a high lymph node yield and its impact on survival. The lymph node ratio was determined in patients with fewer than 12 or at least 12 evaluated nodes. The study included patients after radical colon cancer resection in UICC stages II and III. For the lymph node ratio (LNR) analysis, node-positive patients were divided into four categories: i.e., LNR 1 (p = 0.027). The LNR groups showed a significant association with OS, reaching from 75.5% for LNR 1 to 33.1% for LNR 4 (p < 0.001) in the ≥12 cohort, and from 74.8% for LNR2 to 49.3% for LNR4 (p = 0.007) in the
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- 2024
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26. Mental condition and physical activity of individuals working during the COVID-19 pandemic in Poland
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Jolanta Zwolińska, Paweł Walski, and Kamil Zajdel
- Subjects
quality of life ,depression ,physical activity ,life satisfaction ,covid-19 ,occupational medicine ,Medicine - Abstract
Objectives The study assessed quality of life and depression in working people during COVID-19 pandemic, relative to their physical activity. Material and Methods The study involved 1194 people living in south-eastern Poland, and assessed life satisfaction ( Life Satisfaction Questionnaire – 9 [LISAT-9]), quality of life ( World Health Organization Quality of Life – BREF [WHOQoL-BREF]), depression ( Beck Depression Inventory [BDI]) and physical activity. Results The respondents on average scored 4.32 in LISAT-9; respectively 66.2, 68.3, 69.6 and 63.5 in physical, psychological, social and environment domains of WHOQoL-BREF and 9.2 in BDI. Regularly performed physical activity positively affected the scores in all the psychometric tests in women with higher and secondary education and in men with vocational education. Women presented lower life satisfaction, poorer quality of life and higher level of depression than men. The psychometric scores were also differentiated by type of employment and job. Depression was identified in 44% of all the respondents. Conclusions Individuals who are economically active during the pandemic report good quality of life and no or only mild signs of depression. Working people with higher education cope more effectively with adversities of the pandemic, compared to those with lower education. Int J Occup Med Environ Health. 2023;36(2):274–90
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- 2023
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27. Role of Some microRNA/ADAM Proteins Axes in Gastrointestinal Cancers as a Novel Biomarkers and Potential Therapeutic Targets—A Review
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Agnieszka Kalita, Magdalena Sikora-Skrabaka, and Ewa Nowakowska-Zajdel
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gastrointestinal cancers ,microRNA/miR ,ADAM proteins ,biomarkers ,Biology (General) ,QH301-705.5 - Abstract
Gastrointestinal (GI) cancers are some of the most common cancers in the world and their number is increasing. Their etiology and pathogenesis are still unclear. ADAM proteins are a family of transmembrane and secreted metalloproteinases that play a role in cancerogenesis, metastasis and neoangiogenesis. MicroRNAs are small single-stranded non-coding RNAs that take part in the post-transcriptional regulation of gene expression. Some ADAM proteins can be targets for microRNAs. In this review, we analyze the impact of microRNA/ADAM protein axes in GI cancers.
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- 2023
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28. Finite velocity of ECG signal propagation: preliminary theory, results of a pilot experiment and consequences for medical diagnosis
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Teodor Buchner, Maryla Zajdel, Kazimierz Pȩczalski, and Paweł Nowak
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Medicine ,Science - Abstract
Abstract A satisfactory model of the biopotentials propagating through the human body is essential for medical diagnostics, particularly for cardiovascular diseases. In our study, we develop the theory, that the propagation of biopotential of cardiac origin (ECG signal) may be treated as the propagation of low-frequency endogenous electromagnetic wave through the human body. We show that within this approach, the velocity of the ECG signal can be theoretically estimated, like for any other wave and physical medium, from the refraction index of the tissue in an appropriate frequency range. We confirm the theoretical predictions by the comparison with a direct measurement of the ECG signal propagation velocity and obtain mean velocity as low as v=1500 m/s. The results shed new light on our understanding of biopotential propagation through living tissue. This propagation depends on the frequency band of the signal and the transmittance of the tissue. This finding may improve the interpretation of the electric measurements, such as ECG and EEG when the frequency dependence of conductance and the phase shift introduced by the tissue is considered. We have shown, that the ECG propagation modifies the amplitude and phase of signal to a considerable extent. It may also improve the convergence of inverse problem in electrocardiographic imaging.
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- 2023
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29. Pauzy wypełnione w wystąpieniach naukowych online
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Beata Ciecierska-Zajdel
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pauzy wypełnione ,zaburzenia płynności wypowiedzi ,wystąpienia publiczne ,Philology. Linguistics ,P1-1091 - Abstract
Autorka przeprowadziła analizę 40 naukowych i popularnonaukowych wystąpień zrealizowanych w formie online, aby ustalić frekwencję oraz rodzaje pojawiających się w nich pauz wypełnionych (PW). Badanie wykazało, że w pięciu minutach wypowiedzi o charakterze naukowym występuje średnio 41 dodatkowych, semantycznie niespecyficznych elementów brzmieniowych. Najwyższą frekwencję (blisko 70% zanotowanych PW) miały pauzy wypełnione właściwe (PWW), czyli dźwięki przypominające przedłużone samogłoski lub sylaby: eee, yyy, emmm. Inne zaobserwowane formy wypełniania pauz to przedłużenia wygłosu, powtórzenia wyrazów lub fragmentów fraz, wyrazy retardacyjne (prawda, no, tak) oraz odgłosy niejęzykowe (cmoknięcia, chrząknięcia). Percepcyjnie przedłużenia wyrazów oraz powtórzenia wydają się bardziej przyjazne odbiorcy niż PWW lub wyrazy retardacyjne.
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- 2023
30. Ferromagnetic van der Waals compound MnSb$_{1.8}$Bi$_{0.2}$Te$_4$
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Chen, Yangyang, Chuang, Ya-Wen, Lee, Seng Huat, Zhu, Yanglin, Honz, Kevin, Guan, Yingdong, Wang, Yu, Wang, Ke, Mao, Zhiqiang, Heikes, Colin, Quarterman, P., Zajdel, Pawel, Borchers, Julie A., Ratcliff II, William, and Zhu, Jun
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Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Materials Science - Abstract
The intersection of topology and magnetism represents a new playground to discover novel quantum phenomena and device concepts. In this work, we show that a van der Waals compound MnSb$_{1.8}$Bi$_{0.2}$Te$_4$ exhibits a ferromagnetic ground state with a Curie temperature of 26 K, in contrast to the antiferromagnetic order previously found for other members of the Mn(Sb, Bi)$_2$Te$_4$ family. We employ magneto-transport, bulk magnetization and neutron scattering studies to illustrate the magnetic and electrical properties of MnSb$_{1.8}$Bi$_{0.2}$Te$_4$ and report on the observation of an unusual anomalous Hall effect. Our results are an important step in the synthesis and understanding of ferromagnetic topological insulators.
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- 2019
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31. Bubbles enable volumetric negative compressibility in metastable elastocapillary systems
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Caprini, Davide, Battista, Francesco, Zajdel, Paweł, Di Muccio, Giovanni, Guardiani, Carlo, Trump, Benjamin, Carter, Marcus, Yakovenko, Andrey A., Amayuelas, Eder, Bartolomé, Luis, Meloni, Simone, Grosu, Yaroslav, Casciola, Carlo Massimo, and Giacomello, Alberto
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- 2024
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32. Synchronous recording of magnetocardiographic and electrocardiographic signals
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Pȩczalski, Kazimierz, Sobiech, Judyta, Buchner, Teodor, Kornack, Thomas, Foley, Elizabeth, Janczak, Daniel, Jakubowska, Małgorzata, Newby, David, Ford, Nancy, and Zajdel, Maryla
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- 2024
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33. GENESIS: co-location of geodetic techniques in space
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Pacôme Delva, Zuheir Altamimi, Alejandro Blazquez, Mathis Blossfeld, Johannes Böhm, Pascal Bonnefond, Jean-Paul Boy, Sean Bruinsma, Grzegorz Bury, Miltiadis Chatzinikos, Alexandre Couhert, Clément Courde, Rolf Dach, Véronique Dehant, Simone Dell’Agnello, Gunnar Elgered, Werner Enderle, Pierre Exertier, Susanne Glaser, Rüdiger Haas, Wen Huang, Urs Hugentobler, Adrian Jäggi, Ozgur Karatekin, Frank G. Lemoine, Christophe Le Poncin-Lafitte, Susanne Lunz, Benjamin Männel, Flavien Mercier, Laurent Métivier, Benoît Meyssignac, Jürgen Müller, Axel Nothnagel, Felix Perosanz, Roelof Rietbroek, Markus Rothacher, Harald Schuh, Hakan Sert, Krzysztof Sosnica, Paride Testani, Javier Ventura-Traveset, Gilles Wautelet, and Radoslaw Zajdel
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GENESIS satellite ,Reference systems ,Geodesy ,Geophysics ,Navigation ,Positioning ,Geography. Anthropology. Recreation ,QB275-343 ,Geology ,QE1-996.5 - Abstract
Abstract Improving and homogenizing time and space reference systems on Earth and, more specifically, realizing the Terrestrial Reference Frame (TRF) with an accuracy of 1 mm and a long-term stability of 0.1 mm/year are relevant for many scientific and societal endeavors. The knowledge of the TRF is fundamental for Earth and navigation sciences. For instance, quantifying sea level change strongly depends on an accurate determination of the geocenter motion but also of the positions of continental and island reference stations, such as those located at tide gauges, as well as the ground stations of tracking networks. Also, numerous applications in geophysics require absolute millimeter precision from the reference frame, as for example monitoring tectonic motion or crustal deformation, contributing to a better understanding of natural hazards. The TRF accuracy to be achieved represents the consensus of various authorities, including the International Association of Geodesy (IAG), which has enunciated geodesy requirements for Earth sciences. Moreover, the United Nations Resolution 69/266 states that the full societal benefits in developing satellite missions for positioning and Remote Sensing of the Earth are realized only if they are referenced to a common global geodetic reference frame at the national, regional and global levels. Today we are still far from these ambitious accuracy and stability goals for the realization of the TRF. However, a combination and co-location of all four space geodetic techniques on one satellite platform can significantly contribute to achieving these goals. This is the purpose of the GENESIS mission, a component of the FutureNAV program of the European Space Agency. The GENESIS platform will be a dynamic space geodetic observatory carrying all the geodetic instruments referenced to one another through carefully calibrated space ties. The co-location of the techniques in space will solve the inconsistencies and biases between the different geodetic techniques in order to reach the TRF accuracy and stability goals endorsed by the various international authorities and the scientific community. The purpose of this paper is to review the state-of-the-art and explain the benefits of the GENESIS mission in Earth sciences, navigation sciences and metrology. This paper has been written and supported by a large community of scientists from many countries and working in several different fields of science, ranging from geophysics and geodesy to time and frequency metrology, navigation and positioning. As it is explained throughout this paper, there is a very high scientific consensus that the GENESIS mission would deliver exemplary science and societal benefits across a multidisciplinary range of Navigation and Earth sciences applications, constituting a global infrastructure that is internationally agreed to be strongly desirable. Graphical Abstract
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- 2023
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34. Selfie in the opinions of respondents in the Polish-Czech borderlands
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Krzysztof Zajdel
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selfie ,intimate selfie ,czech republic ,poland ,Education ,Psychology ,BF1-990 - Abstract
This article deals with the selfie phenomenon among a significant percentage of young people. The main objective of my research took the form of questions: — how much of the study group takes selfies and posts them on social media? — how much does possible satisfaction/lack of satisfaction with life result in taking a selfie? Research strategy: two groups of students: from Poland and the Czech Republic. Purposive random selection. The research method is a diagnostic survey, the technique is a questionnaire, while the tool is a survey questionnaire consisting of extensive 15 questions. I found it interesting to compare the two groups of respondents, that is, young people from Poland and the Czech Republic. I tried to find out why they do so and whether it is due to, for example, satisfaction with life. I tried to look for differences on both sides of the border, if any.
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- 2022
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35. Online Auctions End Time and its Impact on Sales Success – Analysis of the Odds Ratio on a Selected Central European Market
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Zakonnik Łukasz, Czerwonka Piotr, and Zajdel Radosław
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online auction ,online sale ,end time ,bidding ,e-commerce ,l81 ,m21 ,Finance ,HG1-9999 ,Economic theory. Demography ,HB1-3840 - Abstract
Research background: E-commerce is developing rapidly, especially during the Covid19 pandemic. This fact can benefit individuals who want to sell their already used goods. Importantly, for sellers, it is not always a priority to get the highest price, but sometimes it is simply effective to get rid of the goods at a satisfactory price.
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- 2022
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36. Effect of Time Between Carbon Dioxide Treatments on the Onset of Oviposition in Queen Honey Bees
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Gąbka Jakub, Gąbka Joanna, and Zajdel Barbara
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anaesthesia ,carbon dioxide treatment ,instrumental insemination ,onset of oviposition ,queen honey bee ,virgin queen ,Zoology ,QL1-991 - Abstract
It is commonly known that two carbon dioxide treatments accelerate the beginning of egg laying in honey bee queens. However, the minimum time between anaesthesias needed for ovary activation has not yet been examined. The aim of the study was to investigate the effect of time between carbon dioxide treatments on the onset of oviposition in instrumentally inseminated and virgin queen honey bees. About half of the queens were anaesthetised before insemination and a second time during insemination, and the rest of the queens were anaesthetised two times without insemination. The time between carbon dioxide treatments was as follows: 96, 48, 24, 12, 6, 3 hrs, 10 min, 5–6 sec. Queens in a control group were anaesthetised only once. The mean number of days between the second treatment and the onset of oviposition in particular groups and in the control group was 10.3, 7.6, 9.9, 10.5, 7.8, 10.9, 14.2, 15 and 21.9, respectively, and the median was 9, 7, 7, 8, 7, 8.5, 11.5, 13 and 21 days, respectively. Queens in groups 5–6 sec and 10 min began oviposition significantly earlier than those in control group, but significantly later than in groups from 3 to 96 hrs. Instrumentally inseminated queens started to lay eggs at the same time (mean 12 and median 9 days after second treatment) as queens treated with carbon dioxide without insemination (mean 11.7 and median 9 days).
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- 2022
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37. The Variability of Tryptophan Metabolism in Patients with Mixed Type of Irritable Bowel Syndrome
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Jan Chojnacki, Paulina Konrad, Marta Mędrek-Socha, Aleksandra Kaczka, Aleksandra Błońska, Radosław Zajdel, Cezary Chojnacki, and Anita Gąsiorowska
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irritable bowel syndrome ,tryptophan metabolism ,gut microbiome ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Patients with a mixed type of irritable bowel syndrome (IBS-M) experience constipation and diarrhea, which alternate between weeks or months. The pathogenesis of this syndrome is still little understood. The aim of the study was mainly to evaluate the urinary excretion of selected tryptophan (TRP) metabolites during the constipation and diarrhea periods of this syndrome. In 36 patients with IBS-M and 36 healthy people, serum serotonin level was measured by ELISA and urinary levels of 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN) and indican (3-IS) were determined using the LC-MS/MS method. The levels of all above metabolites were higher in the patient group, and increased significantly during the diarrheal period of IBS-M. In particular, the changes concerned 5-HIAA (3.67 ± 0.86 vs. 4.59 ± 0.95 mg/gCr, p < 0.001) and 3-IS (80.2 ± 17.4 vs. 93.7 ± 25.1 mg/g/Cr, p < 0.001). These changes coexisted with gut microbiome changes, assessed using hydrogen-methane and ammonia breath tests. In conclusion, the variability of TRP metabolism and the gut microbiome may cause the alternation of IBS-M symptoms.
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- 2024
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38. Quantification of the Post-Fire Strength Retention Factors for Selected Standard Duplex and Lean Duplex Stainless Steel Grades
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Mariusz Maslak, Krzysztof Pancikiewicz, Michal Pazdanowski, Marek Stankiewicz, Piotr Wozniczka, and Paulina Zajdel
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stainless steel ,standard duplex steel ,lean duplex steel ,post-fire strength ,post-fire ductility ,retention factors ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
The experimental quantification of retention factors related to the post-fire strength as well as the post-fire ductility of intentionally selected stainless steel grades applied in construction is the objective of the research presented here. These steel grades are characterized by a two-phase austenitic–ferritic microstructure of the duplex type. In this context, two mutually corresponding chromium–nickel–molybdenum steel grades are subjected to analysis, namely X2CrNiMoN22-5-3 steel belonging to the standard duplex group (DSS 22% Cr) and X2CrMnNiN21-5-1 steel belonging to the lean duplex group (LDSS). The similarities and differences in the mechanical properties exhibited by these steel grades after effective cooling, following more or less prolonged simulated fire action conforming to several development scenarios, are identified and indicated. The resistance of a given steel grade to permanent structural changes induced by the heating program proved to be the critical factor determining these properties and resulting in many cases in increased susceptibility to brittle fracture. The results obtained experimentally seem to confirm the quantitative estimates of post-fire retention factors forecast by Molkens and his team, specified for the steels exhibiting a duplex-type structure and tested by us. However, several of these estimates might be considered somewhat risky. Nevertheless, our results do not confirm the significant post-fire strengthening of steel grades belonging to the LDSS group following prior heating at a sufficiently high temperature, as reported earlier by Huang Yuner and B. Young.
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- 2024
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39. In Vitro Evaluation and In Silico Calculations of the Antioxidant and Anti-Inflammatory Properties of Secondary Metabolites from Leonurus sibiricus L. Root Extracts
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Anna Merecz-Sadowska, Przemysław Sitarek, Tomasz Kowalczyk, Marcin Palusiak, Marta Hoelm, Karolina Zajdel, and Radosław Zajdel
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anti-inflammatory properties ,antioxidant properties ,AtPAP1 ,Leonurus sibiricus L. ,root extract ,transgenic root extract ,Organic chemistry ,QD241-441 - Abstract
Leonurus sibiricus L. has great ethnobotanical and ethnomedicinal significance. This study aimed to assess the antioxidant and anti-inflammatory properties of Leonurus sibiricus L. transgenic roots extracts transformed by Rhizobium rhizogenes, with and without the AtPAP1 transcriptional factor. The study determined the total phenolic and flavonoid contents, as well as in vitro antioxidant assays, including hydrogen peroxide and nitric oxide scavenging activity. In addition, in silico computational studies and molecular docking were conducted to evaluate the antioxidant and anti-inflammatory potential of the identified compounds. The ligands were docked to NADPH oxidase, cyclooxygenase 2,5-lipoxygenase, inducible nitric synthase and xanthine oxidase: enzymes involved in the inflammatory process. The total phenolic and flavonoid contents ranged from 85.3 ± 0.35 to 57.4 ± 0.15 mg/g GAE/g and 25.6 ± 0.42 to 18.2 ± 0.44 mg/g QUE/g in hairy root extracts with and without AtPAP1, respectively. H2O2 scavenging activity (IC50) was found to be 29.3 µg/mL (with AtPAP1) and 37.5 µg/mL (without AtPAP1 transcriptional factor), and NO scavenging activity (IC50) was 48.0 µg/mL (with AtPAP1) and 68.8 µg/mL (without AtPAP1 transcriptional factor). Leonurus sibiricus L. transformed root extracts, both with and without AtPAP1, are a source of phytochemicals belonging to different classes of molecules, such as flavonoids (catechin and rutin), phenolic compounds (caffeic acid, coumaric acid, chlorogenic acid, ferulic acid) and phenylpropanoid (verbascoside). Among the radicals formed after H removal from the different -OH positions, the lowest bond dissociation enthalpy was observed for rutin (4′-OH). Rutin was found to bind with cyclooxygenase 2, inducible nitric synthases and xanthine oxidase, whereas chlorogenic acid demonstrated optimal binding with 5-lipoxygenase. Therefore, it appears that the Leonurus sibiricus L. transformed root extract, both with and without the AtPAP1 transcriptional factor, may serve as a potential source of active components with antioxidant and anti-inflammatory potential; however, the extract containing AtPAP1 demonstrates superior activities. These properties could be beneficial for human health.
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- 2023
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40. Changes in the microstructure of selected structural alloy steel grades identified after their simulated exposure to fire temperature
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Krzysztof Pańcikiewicz, Mariusz Maślak, Michał Pazdanowski, Marek Stankiewicz, and Paulina Zajdel
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Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Results of research on changes in microstructure of selected steel grades used in construction, observed in cooled state after prior exposure to fire temperature are presented in this paper. The following steel grades have been analyzed in detail: S355J2+N, X20Cr13, X6CrNiTi18–10 and X2CrNiMoN22–5–3. These grades are considered to be representative for classic low alloy structural steel of ferritic-pearlitic structure, and several special grades of stainless steel varying in microstructure: martensitic, austenitic and mixed, austenitic-ferritic of duplex type. Analysis of post-fire susceptibility to initiation and unconstrained propagation of brittle failure was the basic purpose of this research. This property seems to be the key one in the context of potential post-fire continued service of these steels when subjected to load. The presented results seem to correlate well with the results of toughness test conducted on the same steels (presented in [6]). The scenarios of sample heating and long term keeping up in the high temperature, and in particular the temperature levels assumed by the authors have been intentionally selected to enable or exclude the chance of expected structural changes occurring in the material subjected to experiment. The varied effective cooling modes have been designed to simulate the slow cooling in the open air or alternatively, rapid cooling during firefighting action conducted by fire brigade.
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- 2023
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41. Global Geodetic Observing System in Poland 2019–2022
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Krzysztof Sosnica, Radoslaw Zajdel, and Jaroslaw Bosy
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gnss ,ggos ,slr ,space ties ,genesis ,Geodesy ,QB275-343 - Abstract
This paper summarizes the contribution of Polish scientific units to the development of the Global Geodetic Observing System (GGOS) in recent years. We discuss the issues related to the integration of space geodetic techniques and co-location in space onboard Global Navigation Satellites Systems (GNSS) and Low Earth Orbiters (LEO), as well as perspectives introduced by the new European Space Agency’s (ESA) mission GENESIS. We summarize recent developments in terms of the European Galileo system and its contribution to satellite geodesy and general relativity, as well as ESA’s recent initiative – Moonlight to establish a satellite navigation and communication system for the Moon. Recent progress in troposphere delay modeling in Satellite Laser Ranging (SLR) allowed for better handling of systematic errors in SLR, such as range biases and tropospheric biases. We discuss enhanced tropospheric delay models for SLR based on numerical weather models with empirical corrections, which improve the consistency between space geodetic parameters derived using different techniques, such as SLR, GNSS, and Very Long Baseline Interferometry (VLBI). Finally, we review recent progress in the development of Polish GGOS scientific infrastructure in the framework of the European Plate Observing System project EPOS-PL¸.
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- 2023
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42. Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
- Author
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Kavai, Mariam, Giannakis, Ioannis, Leshen, Justin, Friedman, Joel, Zajdel, Pawel, and Aynajian, Pegor
- Subjects
Condensed Matter - Strongly Correlated Electrons - Abstract
The quest to understand correlated electronic systems has pushed the frontiers of experimental measurements toward the development of new experimental techniques and methodologies. Here we use a novel home-built uniaxial-strain device integrated into our variable temperature scanning tunneling microscope that enables us to controllably manipulate in-plane uniaxial strain in samples and probe their electronic response at the atomic scale. Using scanning tunneling microscopy with spin-polarization techniques, we visualize antiferromagnetic domains and their atomic structure in Fe1+yTe samples, the parent compound of iron-based superconductors, and demonstrate how these domains respond to applied uniaxial strain. We observe the bidirectional antiferromagnetic domains in the unstrained sample, with an average domain size of 50 to 150 nm, to transition into a single unidirectional domain under applied uniaxial strain. The findings presented here open a new direction to utilize a valuable tuning parameter in scanning tunneling microscopy, as well as other spectroscopic techniques, both for tuning the electronic properties as for inducing symmetry breaking in quantum material systems., Comment: 17 pages, 8 Figures
- Published
- 2018
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43. Dry age-related macular degeneration - therapeutic possibilities and research directions
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Alicja Zajdel
- Subjects
dry-age-related macular degeneration ,wet-age-related macular degeneration ,drug therapy ,Pharmacy and materia medica ,RS1-441 - Abstract
Age-related macular degeneration (AMD) is a major cause of vision loss in developed countries, especially in the elderly population. AMD is a multifactorial disease which etiology is not completely understood. Studies confirm the strong relationship between age and AMD, probably as a result of the complex interaction of metabolic, functional, genetic, and environmental factors that cause important changes in the macular structure (i.e., choriocapillary, Bruch’s membrane, retinal pigmented epithelium, and photoreceptors) that define the symptoms of the disease. Clinically there are two forms of AMD- dry (atrophic) and wet (neovascular). Currently, the gold standard of treatment in wet AMD is the immediate introduction of anti-VEGF (VEGF, vascular endothelial growth factor) therapy in the form of intravitreal injections. There are four preparations of anti-VEGF drugs available in Poland. The three approved for ophthalmic indications are ranibizumab (Lucentis), aflibercept (Eylea), brolucisumab (Beovu) and off-label bevacizumab (Avastin). There are no effective treatments for dry AMD. Currently, the management of dry AMD comes down to preventing the progression of an existing degeneration and - more importantly - inhibiting its transition to neovascular form. Counseling on the need to modify lifestyle by switching to the antioxidant-rich diet, stopping smoking, controlling blood pressure, body weight, using glasses with protective filters, visual rehabilitation and vitamin supplementation (according to the results of the AREDS study) may reduce the risk of the disease progression. Currently, intensive research is underway to develop effective therapeutic solutions in the dry form of AMD, they include the search for substances with antioxidant, anti-inflammatory, neuroprotective properties, complement cascade inhibitors, as well as gene therapy and cell transplantation. New treatment studies are focused on preventing the progression of degeneration and repopulating the atrophic macula. This article reviews the current options and future perspectives for the treatment of AMD, particularly its dry form.
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- 2022
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44. ADAM10 and ADAM17 as Biomarkers Linked to Inflammation, Metabolic Disorders and Colorectal Cancer
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Magdalena Sikora-Skrabaka, Katarzyna Weronika Walkiewicz, Ewa Nowakowska-Zajdel, Dariusz Waniczek, and Joanna Katarzyna Strzelczyk
- Subjects
ADAM10 ,ADAM17 ,colorectal cancer ,biomarkers ,diabetes mellitus type 2 ,cardiovascular diseases ,Biology (General) ,QH301-705.5 - Abstract
ADAM10 and ADAM17 have a role in inflammation and diseases associated with inflammation, such as diabetes, cardiovascular diseases (CVD) or cancer, e.g., colorectal cancer (CRC). The aim of this study was to evaluate whether ADAM10 and ADAM17 could be biomarkers of CRC. To achieve this goal, CRC tumors and a surgical margin from 72 patients with CRC were collected. The concentration of ADAM proteins was measured by the ELISA method. Results were analyzed statistically and compared with selected clinical parameters. We found that ADAM17 protein concentration in the tumor samples was higher in patients with diabetes mellitus type 2 (DMT2) (0.28 vs. 0.2 ng/µg protein; p = 0.01) and in the surgical margin was higher both in patients with coexisting DMT2 (0.22 vs. 0.16 ng/µg protein; p < 0.05) and CVD (0.21 vs. 0.13 ng/µg protein; p < 0.01). The concentration of ADAM10 was higher in the surgical margin than in the tumor (249.34 vs. 228.82 pg/µg protein), and the concentration of ADAM17 was higher in the tumor than in the margin (0.23 vs. 0.18 ng/µg protein), but results were not statistically significant. In conclusion, the results of our study indicate that ADAM10 and ADAM17 may be potential biomarkers in cancer linked with DMT2 and CVD as diseases associated with inflammation.
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- 2022
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45. Life under stay-at-home orders: a panel study of change in social interaction and emotional wellbeing among older Americans during COVID-19 pandemic
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Jielu Lin, Melissa Zajdel, Krystyna R. Keller, Fiona O. Gilpin Macfoy, Philip Shaw, Brenda Curtis, Lyle Ungar, and Laura Koehly
- Subjects
Social Relationships ,Social Support ,Stress ,COVID-19 ,Older Adults ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Recent research has shown the mental health consequence of social distancing during the COVID-19 pandemic, but longitudinal data are relatively scarce. It is unclear whether the pattern of isolation and elevated stress seen at the beginning of the pandemic persists over time. This study evaluates change in social interaction over six months and its impact on emotional wellbeing among older adults. Methods We drew data from a panel study with six repeated assessments of social interaction and emotional wellbeing conducted monthly May through October 2020. The sample included a total of 380 White, Black and Hispanic participants aged 50 and over, of whom 33% had low income, who residing in fourteen U.S. states with active stay-at-home orders in May 2020. The analysis examined how change in living arrangement, in-person interaction outside the household, quality of relationship with family and friends, and perceived social support affected trajectories of isolation stress, COVID worry and sadness. Results While their living arrangements (Odds Ratio [OR] = 0.95, 95% Confidence Interval [CI] = 0.87, 1.03) and relationship quality (OR = 0.94, 95% CI = 0.82, 1.01) remained stable, older adults experienced fluctuations in perceived social support (linear Slope b = -1.42, s.e. = 0.16, p
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- 2022
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46. Effects of ketamine optical isomers, psilocybin, psilocin and norpsilocin on time estimation and cognition in rats
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Popik, Piotr, Hogendorf, Adam, Bugno, Ryszard, Khoo, Shaun Yon-Seng, Zajdel, Pawel, Malikowska-Racia, Natalia, Nikiforuk, Agnieszka, and Golebiowska, Joanna
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- 2022
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47. Serum IL-5, POSTN and IL-33 levels in chronic rhinosinusitis with nasal polyposis correlate with clinical severity
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Hanna Zielińska-Bliźniewska, Milena Paprocka-Zjawiona, Anna Merecz-Sadowska, Radosław Zajdel, Katarzyna Bliźniewska-Kowalska, and Katarzyna Malinowska
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Chronic rhinosinusitis ,IL-5 ,POSTN ,IL-33 ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Abstract Background Chronic rhinosinusitis (CRS) is a group of heterogeneous diseases characterized by epithelial inflammation and tissue eosinophilic infiltration. IL-5, POSTN, and IL-33 are important factors that act as chemoattractants for eosinophils, and a tissue-remodeling protein positively correlated with eosinophils in blood and mediators of eosinophilic infiltration. The aim of the study was to determine the expression of IL-5, POSTN and IL-33, at the gene and protein levels, in eosinophilic CRS with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP), and to correlate this expression with clinical severity. Materials and methods The study included 40 CRSwNP patients and 53 CRSsNP patients and 40 control subjects. The expression of IL-5, POSTN and IL-33 mRNA was determined in sinonasal mucosal samples and in nasal polyp tissue by real-time PCR. Protein levels in the serum of CRSwNP patients were measured by ELISA. Computed tomography was evaluated according to Lund–Mackay scores, and visual analog scale scores were assessed. Results NP tissue demonstrated significantly higher IL-5 and POSTN mRNA expression than the sinonasal tissue in the CRSsNP and CRSwNP groups. CRS groups demonstrated elevated IL-33 mRNA expression in comparison to controls irrespective of the presence of NP. No correlation was found between IL-5, POSTN and IL-33 mRNA expression and disease severity. CRSwNP group demonstrated significantly higher serum IL-5, POSTN and IL-33 protein levels than controls, and this corresponds to disease severity. Conclusion Serum IL-5, POSTN and IL-33 levels may be important markers for classification of eosinophilic CRSwNP patients, along with disease severity.
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- 2022
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48. Food Anthocyanins: Malvidin and Its Glycosides as Promising Antioxidant and Anti-Inflammatory Agents with Potential Health Benefits
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Anna Merecz-Sadowska, Przemysław Sitarek, Tomasz Kowalczyk, Karolina Zajdel, Mariusz Jęcek, Paweł Nowak, and Radosław Zajdel
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malvidin ,malvidin glycosides ,antioxidant activity ,anti-inflammatory activity ,health benefits ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Anthocyanins are flavonoid compounds that are abundantly present in fruits and vegetables. These compounds contribute to the color of these foods and offer various health benefits to consumers due to their biological properties. There are more than 1000 types of anthocyanins in nature, all derived from 27 anthocyanidin aglycones that have different glycosylations and acylations. Malvidin is one of the most well-known anthocyanidins. Several studies, including those conducted on cell lines, animals, and humans, have suggested that malvidin and its glycosides possess anti-carcinogenic, diabetes-control, cardiovascular-disease-prevention, and brain-function-improvement properties. These health benefits are primarily attributed to their antioxidant and anti-inflammatory effects, which are influenced by the molecular mechanisms related to the expression and modulation of critical genes. In this article, we review the available information on the biological activity of malvidin and its glycosides concerning their health-promoting effects.
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- 2023
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49. Rectal Cancer: Are 12 Lymph Nodes the Limit?
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Paweł Mroczkowski, Łukasz Dziki, Tereza Vosikova, Ronny Otto, Anna Merecz-Sadowska, Radosław Zajdel, Karolina Zajdel, Hans Lippert, and Olof Jannasch
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rectal cancer ,lymph nodes ,low anterior resection ,abdominoperineal amputation ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Lymph node dissection is a crucial element of oncologic rectal surgery. Many guidelines regard the removal of at least 12 lymph nodes as the quality criterion in rectal cancer. However, this recommendation remains controversial. This study examines the factors influencing the lymph node yield and the validity of the 12-lymph node limit. Patients with rectal cancer who underwent low anterior resection or abdominoperineal amputation between 2000 and 2010 were analyzed. In total, 20,966 patients from 381 hospitals were included. Less than 12 lymph nodes were found in 20.53% of men and 19.31% of women (p = 0.03). The number of lymph nodes yielded increased significantly from 2000, 2005 and 2010 within the quality assurance program for all procedures. The univariate analysis indicated a significant (p < 0.001) correlation between lymph node yield and gender, age, pre-therapeutic T-stage, risk factors and neoadjuvant therapy. The multivariate analyses found T3 stage, female sex, the presence of at least one risk factor and neoadjuvant therapy to have a significant influence on yield. The probability of finding a positive lymph node was proportional to the number of examined nodes with no plateau. There is a proportional relationship between the number of examined lymph nodes and the probability of finding an infiltrated node. Optimal surgical technique and pathological evaluation of the specimen cannot be replaced by a numeric cut-off value.
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- 2023
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50. RINEXAV: GNSS global network selection open-source software based on qualitative analysis of RINEX files
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Filip Gałdyn, Radosław Zajdel, and Krzysztof Sośnica
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IGS ,GNSS ,MGEX ,Data mining ,Geodesy ,Computer software ,QA76.75-76.765 - Abstract
The determination of global geodetic parameters using Global Navigation Satellite System (GNSS) observations requires using a global, evenly distributed network of stations. The homogeneous distribution of stations is crucial for deriving Earth rotation parameters, coordinates of Earth’s center of mass, orbit determination, and the realization of the International Terrestrial Reference Systems. It is necessary to select the most representative group of stations, providing GNSS observations of the best quality, i.e. taking into account the factors, such as the number of observations, measured signal-to-noise ratio, or signal multipath indicator. This paper provides a description of the open-source software RINEXAV to select and optimize the GNSS station network based on the qualitative analysis of RINEX files. The provided software allows users to maximize the number of observations based on specified criteria, maintain the uniform distribution of stations, and automatically select the most suitable stations from among those available. To accomplish this, the software uses multi-criteria decision-making and clustering methods. The paper provides the description, use and impact of the RINEXAV software in geosciences.
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- 2023
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