250 results on '"Sandra Carvalho"'
Search Results
2. Deep Learning Approach to the Texture Optimization Problem for Friction Control in Lubricated Contacts
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Alexandre Silva, Veniero Lenzi, Sergey Pyrlin, Sandra Carvalho, Albano Cavaleiro, and Luís Marques
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General Physics and Astronomy - Published
- 2023
3. Laser texturing of piston ring for tribological performance improvement
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Rita Ferreira, Óscar Carvalho, Luís Sobral, Sandra Carvalho, and Filipe Silva
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Mechanical Engineering ,Surfaces, Coatings and Films - Abstract
The radial surface coating layer of compression piston rings is used to improve their wear resistance during the internal combustion engine operation. However, at top dead centers, the friction coefficient of the piston ring-cylinder liner pair is detrimental to the engine’s tribological performance. In this work, dimples with different texture dimensions and densities were tested in a home-developed tribometer. The friction coefficient was measured for all samples, and for those with the best results, their wear resistance was assessed. The texture with an aspect ratio of 0.25 and a density area of 15% reported the best tribological results.
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- 2023
4. Psychological factors and healthy sleep in a Portuguese sample of employees with regular working hours
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Beatriz Marques Silva, Sandra Carvalho Bos, António José Vilar Queirós, and António Ferreira Macedo
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Physiology ,Physiology (medical) ,Ecology, Evolution, Behavior and Systematics - Published
- 2022
5. Modulation of the cognitive event-related potential P3 by transcranial direct current stimulation: Systematic review and meta-analysis
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Óscar F. Gonçalves, Kevin Pacheco-Barrios, Jorge Leite, Felipe Fregni, Sandra Carvalho, Augusto J. Mendes, and Alberto Lema
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Cognitive Neuroscience ,medicine.medical_treatment ,Prefrontal Cortex ,Event-related potential P3 P300 ,Emotional processing ,Transcranial Direct Current Stimulation ,tDCS ,050105 experimental psychology ,03 medical and health sciences ,Behavioral Neuroscience ,Cognition ,0302 clinical medicine ,Event-related potential ,medicine ,Humans ,Attention ,0501 psychology and cognitive sciences ,Latency (engineering) ,Inhibitory control ,Evoked Potentials ,Transcranial direct-current stimulation ,Mechanism (biology) ,Working memory ,business.industry ,05 social sciences ,Neuropsychology and Physiological Psychology ,Meta-analysis ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Transcranial direct current stimulation (tDCS) has been widely used to modulate cognition and behavior. However, only a few studies have been probing the brain mechanism underlying the effects of tDCS on cognitive processing, especially throughout electrophysiological markers, such as the P3. This meta-analysis assessed the effects of tDCS in P3 amplitude and latency during an oddball, n-back, and Go/No-Go tasks, as well as during emotional processing. A total of 36 studies were identified, but only 23 were included in the quantitative analysis. The results show that the parietal P3 amplitude increased during oddball and n-back tasks, mostly after anodal stimulation over the left dorsolateral prefrontal cortex (p = 0.018, SMD = 0.4) and right inferior frontal gyrus (p
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- 2022
6. Editorial: TMS application in both health and disease
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Ana Dionísio, Sandra Carvalho, and Joao Castelhano
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Behavioral Neuroscience ,Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Neurology ,Biological Psychiatry - Published
- 2023
7. Plasma Etching of Polycarbonate Surfaces for Improved Adhesion of Cr Coatings
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Pooja Sharma, F. Ponte, M.J. Lima, N.M. Figueiredo, J. Ferreira, and Sandra Carvalho
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- 2023
8. Synergic Effect of Tmd Coating on Textured Steel Using Micro-Edm Technique
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Pooja Sharma, Manoj Rajankunte Mahadeshwara, Luís Vilhena Vilhena, Vipin Richhariya, Filipe Silva, Amílcar Ramalho, Sandra Carvalho, and Albano Cavaleiro
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- 2023
9. A New Tribometer for the Automotive Industry: Development and Experimental Validation
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Óscar Carvalho, Sandra Carvalho, R. Ferreira, J.M. Pires, Filipe Samuel Silva, and Luís Sobral
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Materials science ,Mechanical Engineering ,Aerospace Engineering ,Mechanical engineering ,Tribology ,Compression (physics) ,Durability ,Cylinder (engine) ,law.invention ,Piston ,Internal combustion engine ,Mechanics of Materials ,law ,Piston ring ,Tribometer - Abstract
In automotive engineering, the piston ring-cylinder liner pair is among the most studied contacts. From the three piston rings of a conventional internal combustion engine, the top compression ring has a crucial role. The main challenge is to prevent that during the engine lifecycle, the degradation of the piston ring surface might limit the engine’s durability. However, a reliable evaluation of the piston rings tribological response requires a steady method. To test and study the tribological performance of the ring-liner pair, the development of a customized test rig is presented in this work. The new oscillating tribometer will test and study the performance of new and commercial piston rings and cylinder liner solutions. According to the foreseen engine operation, four conditions were appointed to perform the control tests, and a testing protocol was established. The selected stainless-steel piston rings were coated with a diamond-like carbon layer, and the cylinder liner parts had the typical plateau honed texture in the contact surface. The friction force measures were recorded. It was also investigated the influence of distinct parameters (such as temperature and contact pressure) in the friction coefficient of this pair. According to the exploratory tests, the major COF was registered for the testing condition with a lower load. In contrast, the lower COF values were recorded for those conditions with superior normal loads and temperatures. The functionality of the developed test rig was verified to evaluate the ring's performance and the liner contact.
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- 2021
10. DNDI-6148: A Novel Benzoxaborole Preclinical Candidate for the Treatment of Visceral Leishmaniasis
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Stéphanie Braillard, Jason Speake, Sandra Carvalho, Yvonne Freund, Gavin A. Whitlock, Guy Caljon, Bakela Nare, Paul Alan Glossop, Victoriano Corpas-López, Fabio Zuccotto, Louis Maes, Davide Bello, Ian H. Gilbert, Susan Wyllie, Bharathi Pandi, Iva Lukac, Robert T. Jacobs, Magali Van den Kerkhof, Vanessa Yardley, Charles E. Mowbray, Richard J. Wall, and Stephen Patterson
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Boron Compounds ,Pyridines ,Antiprotozoal Agents ,Cleavage and polyadenylation specificity factor ,Pharmacology ,Article ,Mice ,Structure-Activity Relationship ,03 medical and health sciences ,Dogs ,In vivo ,Cricetinae ,Drug Discovery ,medicine ,Animals ,Humans ,Mode of action ,030304 developmental biology ,Benzoxazoles ,0303 health sciences ,biology ,030306 microbiology ,Chemistry ,Pharmacology. Therapy ,Neglected Disease ,medicine.disease ,Leishmania ,biology.organism_classification ,3. Good health ,Disease Models, Animal ,Safety profile ,Visceral leishmaniasis ,Parasitic disease ,Leishmaniasis, Visceral ,Molecular Medicine - Abstract
Visceral leishmaniasis (VL) is a parasitic disease endemic across multiple regions of the world and is fatal if untreated. Current therapies are unsuitable, and there is an urgent need for safe, short-course, and low-cost oral treatments to combat this neglected disease. The benzoxaborole chemotype has previously delivered clinical candidates for the treatment of other parasitic diseases. Here, we describe the development and optimization of this series, leading to the identification of compounds with potent in vitro and in vivo antileishmanial activity. The lead compound (DNDI-6148) combines impressive in vivo efficacy (>98% reduction in parasite burden) with pharmaceutical properties suitable for onward development and an acceptable safety profile. Detailed mode of action studies confirm that DNDI-6148 acts principally through the inhibition of Leishmania cleavage and polyadenylation specificity factor (CPSF3) endonuclease. As a result of these studies and its promising profile, DNDI-6148 has been declared a preclinical candidate for the treatment of VL.
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- 2021
11. Modification of Steel Surfaces with Nanometer Films of Al2O3 and TiO2 Decreases Interfacial Adhesion to Polymers: Implications for Demolding Shape-Engineered Polymer Products
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Kira Gonzalez, Filipe J. Oliveira, Ricardo M. Silva, Sandra Carvalho, Rui F. Silva, Maria J. Lima, and José D. Castro
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chemistry.chemical_classification ,Materials science ,fungi ,technology, industry, and agriculture ,Interfacial adhesion ,02 engineering and technology ,Molding (process) ,Polymer ,equipment and supplies ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surface energy ,0104 chemical sciences ,Atomic layer deposition ,chemistry.chemical_compound ,chemistry ,Titanium dioxide ,General Materials Science ,Nanometre ,Composite material ,Thin film ,0210 nano-technology - Abstract
Alumina (Al2O3) and titanium dioxide (TiO2) thin films were deposited by the atomic layer deposition technique on steel substrates used in the polymer injection molding industry. The modified steel...
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- 2021
12. Author response: High hedgehog signaling is transduced by a multikinase-dependent switch controlling the apico-basal distribution of the GPCR smoothened
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Marina Gonçalves Antunes, Matthieu Sanial, Vincent Contremoulins, Sandra Carvalho, Anne Plessis, and Isabelle Becam
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- 2022
13. CCL3, CCL5, IL-15, IL-1Ra and VEGF compose a reliable algorithm to discriminate classes of adverse events following 17DD-YF primary vaccination according to cause-specific definitions
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Marília Lima Cruz Rocha, Eva Lídia Arcoverde Medeiros, Izabela Maurício de Rezende, Valeria Valim, Maira Alves Pereira, Matheus de Souza Gomes, Ana Carolina Campi-Azevedo, Daniel Garkauskas Ramos, Josiane Dias Gusmão, Maria Auxiliadora-Martins, Talita Émile Ribeiro Adelino, Regina Coeli Magalhães Rodrigues, Marcos Vieira Silva, Andréa Teixeira-Carvalho, Francieli Fontana Sutile Tardetti Fantinato, Alessandro Pecego Martins Romano, Laurence Rodrigues do Amaral, Rodrigo Fabiano do Carmo Said, Glauco de Carvalho Pereira, Sandra Carvalho, Eder Gatti Fernandes, Jordana Rodrigues Barbosa Fradico, Jordana Grazziela Alves Coelho-dos-Reis, Elaine Spezialli Faria, Betânia Paiva Drumond, Vanessa Peruhype-Magalhães, Janaina Fonseca Almeida, Felipe Campos de Melo Iani, José Geraldo Leite Ribeiro, Roberta Barros da Silva, and Olindo Assis Martins-Filho
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Vascular Endothelial Growth Factor A ,VEGF receptors ,030231 tropical medicine ,CCL3 ,Reference range ,CCL5 ,BIOMARCADORES ,03 medical and health sciences ,0302 clinical medicine ,Serum biomarkers ,Yellow Fever ,Humans ,Medicine ,030212 general & internal medicine ,Adverse effect ,Chemokine CCL5 ,Interleukin-15 ,General Veterinary ,General Immunology and Microbiology ,biology ,business.industry ,Vaccination ,Yellow Fever Vaccine ,Public Health, Environmental and Occupational Health ,Interleukin 1 Receptor Antagonist Protein ,Infectious Diseases ,Interleukin 15 ,biology.protein ,Molecular Medicine ,Differential diagnosis ,business ,Algorithm ,Algorithms - Abstract
In the present study, a range of serum biomarkers were quantified in suspected cases of adverse events following YF immunization (YEL-AEFI) to propose a reliable laboratorial algorithm to discriminate confirmed YEL-AEFI (“A1” class) from cases with other illnesses (“C” class). Our findings demonstrated that increased levels of CXCL8, CCL2, CXCL10, IL-1β, IL-6 and TNF-α were observed in YEL-AEFI (“A1” and “C” classes) as compared to primary vaccines without YEL-AEFI [PV(day 3–28)] and reference range (RR) controls. Notably, increased levels of CCL3, CCL4, CCL2, CCL5, IL-1β, IL-15, IL-1Ra and G-CSF were found in “A1” as compared to “C” class. Venn diagrams analysis allowed the pre-selection of biomarkers for further analysis of performance indices. Data demonstrated that CCL3, CCL5, IL-15 and IL-1Ra presented high global accuracy (AUC = 1.00) to discriminate “A1” from “C”. Decision tree was proposed with a reliable algorithm to discriminate YEL-AEFI cases according to cause-specific definitions with outstanding overall accuracy (91%). CCL3, CCL5, IL-15 and IL-1Ra appears as root attributes to identify “A1” followed by VEGF as branch nodes to discriminate Wild Type YFV infection (“C(WT-YFV)”) from cases with other illnesses (“C*”). Together, these results demonstrated the applicability of serum biomarker measurements as putative parameters towards the establishment of accurate laboratorial tools for complementary differential diagnosis of YEL-AEFI cases.
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- 2021
14. Influence of a DLC coating topography in the piston ring/cylinder liner tribological performance
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Filipe Samuel Silva, Óscar Carvalho, Rita Ferreira, Rui Almeida, Luís Sobral, and Sandra Carvalho
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0209 industrial biotechnology ,Materials science ,Strategy and Management ,02 engineering and technology ,Management Science and Operations Research ,Tribology ,021001 nanoscience & nanotechnology ,Compression (physics) ,Industrial and Manufacturing Engineering ,Cylinder (engine) ,law.invention ,Piston ,020901 industrial engineering & automation ,law ,Surface roughness ,Piston ring ,Composite material ,0210 nano-technology ,Surface finishing ,Tribometer - Abstract
In the piston ring-cylinder system, the surface topography is crucial to their tribological performance, emphasizing the relevance of the surface finishing processes. The present work studied the influence of different finishing processes in the surface roughness parameters of the coated compression piston rings. Three distinct surfaces’ finishing processes were used in the first approach: Option A, B, and C. Options D comprised the variation of different processing parameters. The piston rings with different surface topographies were tribologically evaluated using a tribometer developed explicitly for this industrial evaluation. Regarding the tribological performance, it was concluded that the use of the surface finishing processes fostered a decrease in the coefficient of friction. The surface finishing had also impacted the wear of the piston ring and in the counterbody. An increase in the piston rings’ surface roughness led to a rise in the surface's weight loss.
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- 2021
15. Development of Nanocomposite Coating by Hybrid Gas Condensation Process and Magnetron Sputtering Equipment: Electrochemical Characteristics and Surface Analysis
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Albano Cavaleiro, Sandra Carvalho, Isabel Carvalho, S.A. Salehizadeh, and R. Serra
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010302 applied physics ,Materials science ,Mechanical Engineering ,02 engineering and technology ,Sputter deposition ,engineering.material ,021001 nanoscience & nanotechnology ,01 natural sciences ,Dielectric spectroscopy ,Corrosion ,X-ray photoelectron spectroscopy ,Coating ,Chemical engineering ,Mechanics of Materials ,0103 physical sciences ,engineering ,General Materials Science ,0210 nano-technology ,Polarization (electrochemistry) ,Dissolution ,Layer (electronics) - Abstract
In the present work, a combination of conventional dc magnetron sputtering technique and gas condensation process was utilized to deposit a Ag–Au/a:C nanocomposite coating for application in stents. Quantitative evaluation of Ag+ release to the solution revealed a sharp increase of Ag+ releasing in the first 2 days of immersion, which continues but with a slower rate up to 14 days reaching a value close to 50 ppb. Atomic force microscopy surface morphology depicted that the roughness of the coating, Srms, increases after immersion from 5.86 to 14.22. X-ray photoelectron spectroscopy analysis showed two wide bands at 368.30 and 374.30 eV corresponding to the Ag 3d spin-orbit doublets for non-immersed coating. It was found that the Ag content drops to 5% of the initial concentration as the coating is exposed to artificial urine, due to the high affinity of Ag surface nanoparticles to solution anions. This Ag dissolution to artificial urine is followed by reprecipitating Ag salt clusters with a size less than 3 nm on the surface and the formation of a highly oxidized surface. The formation of the oxidation layer as a result of exposure of the coating to the solution is further confirmed by electrochemical impedance spectroscopy and polarization measurements. It was depicted the resistance of the coating increase from 1.80 to 2.86 MΩ as the coating is immersed into the solution for 14 days. The corrosion potential and corrosion current values collected from the polarization plot of the immersed coating were found to be −0.73 and 0.14, respectively, depicting the protecting character of the coating against the deteriorating solution. It was suggested that the formation of the oxidation layer on the coating surface seals the pores of the coating avoiding solution penetration to the substrate and consequently protecting it against corrosion.
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- 2021
16. A Decade of Progress on MAO-Treated Tantalum Surfaces: Advances and Contributions for Biomedical Applications
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Luísa Fialho, Cristiana Alves, and Sandra Carvalho
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General Chemical Engineering ,General Materials Science - Abstract
Micro-structured coatings with functional properties have been investigated due to a wide range of applications. It is known that micro-structures can play an important role in surface interactions determining the materials’ performance. Amongst the other materials, there has been an increasing interest in tantalum oxide (Ta2O5). This attention is mainly due to its variety of properties: biocompatibility and bioactivity; high dielectric constant; good thermal and chemical stability; excellent corrosion and mechanical resistance. Moreover, there is a wide range of applications in which the properties can be fitted. Furthermore, according to the final application, these properties can be enhanced or tailored through surface micro-structures manipulation. Due to this purpose, over the past decade, Ta surface modification by micro-arc oxidation (MAO) has been investigated mostly for biomedical applications. Therefore, this review focuses on Ta surface functionalization using the MAO technique. A clear understanding of the micro-discharge phenomena and the formation mechanism of a Ta2O5 anodic coating by MAO is supplied. The Ta2O5 coating morphology, topography, chemistry, and structure are explored, establishing their correlation with the MAO parameters. Additionally, an understanding of Ta2O5’s biological, mechanical, and electrochemical properties is provided and reviewed.
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- 2022
17. Decorative Chromium Coatings on Polycarbonate Substrate for the Automotive Industry
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Filipa Ponte, Pooja Sharma, Nuno Miguel Figueiredo, Jorge Ferreira, and Sandra Carvalho
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General Materials Science ,polycarbonate ,chromium coating ,plasma etching ,sputtering ,automotive industry - Abstract
Metal-coated plastic parts are replacing traditional metallic materials in the automotive industry. Sputtering is an alternative technology that is more environmentally friendly than electrolytic coatings. Most metalized plastic parts are coated with a thin metal layer (~100–200 nm). In this work, the challenge is to achieve thicker films without cracking or without other defects, such as pinholes or pores. Chromium coatings with different thicknesses were deposited onto two different substrates, polycarbonate with and without a base coat, using dc magnetron sputtering in an atmosphere of Ar. Firstly, in order to improve the coating adhesion on the polymer surface, a plasma etching treatment was applied. The coatings were characterized for a wide thickness range from 800 nm to 1600 nm. As the thickness of the coatings increased, there was an increase in the specular reflectivity and roughness of the coatings and changes in morphology due to the columnar growth of the film and a progressive increase in thermal stresses. Furthermore, a decrease in the hardness and the number of pinholes was noticed. The maximum thickness achieved without forming buckling defects was 1400 nm. The tape tests confirmed that every deposited coating showed a good interface adhesion to both polymers.
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- 2023
18. The impact of physical activity on objective sleep of people with insomnia
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Mariana Francisco Ferreira, Sandra Carvalho Bos, and António Ferreira Macedo
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Psychiatry and Mental health ,Biological Psychiatry - Abstract
The aim of our study was to investigate if physical activity has a beneficial impact on insomnia. A systematic literature review was conducted in PubMed database using the terms "Physical activity" and "Insomnia" and 591 records were retrieved. The preferred reporting items for systematic reviews and meta-analyses guidelines were followed and fifteen articles were considered eligible for further analysis. Participants were mainly female, between 40 and 60 years; design studies were variable and most studies involved long-term interventions; insomnia definition was mainly based on diagnostic criteria or considered a specific cut-off point of well-known insomnia questionnaires; sleep was mostly assessed with polysomnography (PSG) or actigraphy; physical activity interventions included different methodologies (predominantly treadmill exercise). A beneficial effect of physical activity on insomnia was observed in most studies when sleep was evaluated with PSG or actigraphy. Sleep efficiency was the objective sleep parameter that mainly provided statistically significant results, as expected, followed by sleep onset latency, wake after sleep onset and, less frequently, total sleep time. Using objective methods to assess sleep in insomnia might be useful to support subjective insomnia complaints and to evaluate the efficacy of physical activity interventions in ameliorating sleep of people with insomnia.
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- 2023
19. Pyrolysis of Lignocellulosic Waste from Second-Generation Ethanol Industry
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Mozart Daltro Bispo, L. V. O. Sandes, Allan A. Albuquerque, João Inácio Soletti, Livia M. O. Ribeiro, Sandra Carvalho, P. X. O. Bezerra, and Wedja Timóteo Vieira
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0106 biological sciences ,Residue (complex analysis) ,Thermogravimetric analysis ,Moisture ,Chemistry ,04 agricultural and veterinary sciences ,Pulp and paper industry ,01 natural sciences ,Adsorption ,Biochar ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Fourier transform infrared spectroscopy ,Bagasse ,Agronomy and Crop Science ,Pyrolysis ,010606 plant biology & botany - Abstract
Interest on the use of lignocellulosic waste from second-generation (2G) ethanol industry has increased each year, where biochar and bio-oil production by pyrolysis is a relevant alternative. Biochar has high energy, adsorption capacity and soil enrichment potential, while bio-oil has applications for the pharmaceutical, chemical and fuel industries. Nonetheless, research on pyrolysis of this residue has not been reported, nor has the characterization of the bio-oil produced been profiled. Besides this, few studies on biochar and bio-oil produced from sugarcane bagasse have analyzed the effects of temperature and heating rate on yield. This work investigates the production and characterization of biochar and bio-oil by pyrolysis from this 2G waste. Temperature (500–700 °C) and heating rate (5–15 °C min−1) were the variables evaluated using a full factorial design (FFD), while biochar and bio-oil yields were the responses investigated. Characterization was carried out by thermogravimetric analysis, physical and chemical analyses, Fourier transform infrared spectroscopy, dispersive energy X-ray fluorescence spectroscopy (EDS) and gas chromatography–mass spectrometry (GC–MS). From FFD results, linear models were successfully fit to the responses. Maximum biochar and bio-oil yields of 40.3% and 39.0% were found for a set of temperature-heating rates of 500 °C-5 °C min−1 and 700 °C-15 °C min−1, respectively, in agreement with residue from first-generation ethanol process. The biochar presented low content of ash, volatile materials and moisture as well as high fixed carbon content and heating values, showing high energy potential. The bio-oil exhibited alternativity as source of phenols (53.2%) for industry based on the GC–MS results.
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- 2021
20. Elaeis guineensis-activated carbon for methylene blue removal: adsorption capacity and optimization using CCD-RSM
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Allan A. Albuquerque, Alef T. Santos, Sandra Carvalho, João Inácio Soletti, Weslley C. O. Ramos, Leylia K. F. Araújo, and Mozart Daltro Bispo
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Economics and Econometrics ,Langmuir ,Materials science ,biology ,Central composite design ,Geography, Planning and Development ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,Raw material ,biology.organism_classification ,Elaeis guineensis ,01 natural sciences ,Adsorption ,Elaeis ,Chemical engineering ,Biochar ,medicine ,021108 energy ,0105 earth and related environmental sciences ,Activated carbon ,medicine.drug - Abstract
The activated biochar is a carbonaceous material obtained from thermal degradation of biomass with high adsorption potential. On the other hand, the high production cost has still limited its use in large-scale, so that low-cost raw materials derived from biomass have been encouraged. For instance, waste from palm oil industry, such as palm endocarp (Elaeis guineenses), has shown high potential to produce cheaper activated carbon since high amount of palm residues are annually generated worldwide. Moreover, as far as we know, Elaeis guineensis-biochar activated by ZnCl2 has not been tested as an adsorbent for methylene blue (MB) removal. In addition, optimization studies on activation variables focused on maximizing MB removal are still scarce. This work aims to investigate the adsorption capacity of the Elaeis guineensis-activated carbon for MB removal and to find optimized conditions. Thermo-chemical activation was carried out using ZnCl2. Temperature ( $$T$$ ), activation time ( $$t$$ ) and particle size ( $$PS$$ ) were the variables evaluated through a full factorial design. The optimal condition was obtained based on central composite design (CCD) and surface response methodology (RSM) techniques. Kinetic and equilibrium studies were also carried out. CCD and RSM predicted an optimal MB removal of 93.2% adopting 0.05 g of activated biochar, PS = 65 mesh, $$T\hspace{0.17em}$$ = 700 °C and $$t\hspace{0.17em}$$ = 3 h. Kinetic and adsorption equilibrium results agreed to pseudo second-order model and Langmuir’s model, respectively. Finally, Elaeis guineensis showed to be a promising feedstock to produce activated biochar aiming MB removal from water and wastewater.
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- 2021
21. High hedgehog signaling is transduced by a multikinase-dependent switch controlling the apico-basal distribution of the GPCR smoothened
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Marina Gonçalves-Antunes, Matthieu Sanial, Vincent Contremoulins, Sandra Carvalho, Anne Plessis, and et Isabelle Bécam
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animal structures ,Drosophila melanogaster ,General Immunology and Microbiology ,General Neuroscience ,Animals ,Drosophila Proteins ,Drosophila ,Hedgehog Proteins ,General Medicine ,Phosphorylation ,Smoothened Receptor ,General Biochemistry, Genetics and Molecular Biology ,Receptors, G-Protein-Coupled - Abstract
SUMMARYThe oncogenic GPCR Smoothened is a key transducer of the Hedgehog morphogen, which plays essential roles in the patterning of epithelial structures. Here, we examine how Hedgehog controls Smoothened subcellular localization and activity in a polarized epithelium using the Drosophila wing imaginal disc as a model. We provide evidence that Hedgehog promotes the stabilization of Smoothened by switching its fate after endocytosis toward recycling. This effect involves the sequential and additive action of Protein Kinase A, Casein Kinase I and the Fused kinase. Moreover, in the presence of very high levels of Hedgehog, a second effect of Fused leads to the local enrichment of Smoothened in the most basal domain of the cell membrane. Together, these results link the morphogenetic effects of Hedgehog to the apico-basal distribution of Smoothened and provide a novel mechanism for regulation of a GPCR by plasma membrane subcompartimentalisation.
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- 2022
22. Oligo targeting for profiling drug resistance mutations in the parasitic trypanosomatids
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Simone Altmann, Eva Rico, Sandra Carvalho, Melanie Ridgway, Anna Trenaman, Hannah Donnelly, Michele Tinti, Susan Wyllie, and David Horn
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Trypanosoma cruzi ,Mutation ,Trypanosoma brucei brucei ,Genetics ,Drug Resistance ,Animals ,Parasites ,Codon - Abstract
Trypanosomatids cause the neglected tropical diseases, sleeping sickness, Chagas disease and the leishmaniases. Studies on these lethal parasites would be further facilitated by new and improved genetic technologies. Scalable precision editing methods, for example, could be used to improve our understanding of potential mutations associated with drug resistance, a current priority given that several new anti-trypanosomal drugs, with known targets, are currently in clinical development. We report the development of a simple oligo targeting method for rapid and precise editing of priority drug targets in otherwise wild type trypanosomatids. In Trypanosoma brucei, approx. 50-b single-stranded oligodeoxynucleotides were optimal, multiple base edits could be incorporated, and editing efficiency was substantially increased when mismatch repair was suppressed. Resistance-associated edits were introduced in T. brucei cyclin dependent kinase 12 (CRK12, L482F) or cleavage and polyadenylation specificity factor 3 (N232H), in the Trypanosoma cruzi proteasome β5 subunit (G208S), or in Leishmania donovani CRK12 (G572D). We further implemented oligo targeting for site saturation mutagenesis, targeting codon G492 in T. brucei CRK12. This approach, combined with amplicon sequencing for codon variant scoring, revealed fourteen resistance conferring G492 edits encoding six distinct amino acids. The outputs confirm on-target drug activity, reveal a variety of resistance-associated mutations, and facilitate rapid assessment of potential impacts on drug efficacy.
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- 2022
23. Working Memory Training Coupled With Transcranial Direct Current Stimulation in Older Adults: A Randomized Controlled Experiment
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Ana C. Teixeira-Santos, Célia S. Moreira, Diana R. Pereira, Diego Pinal, Felipe Fregni, Jorge Leite, Sandra Carvalho, and Adriana Sampaio
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Aging ,Transfer effects ,Multidisciplinaire, généralités & autres [D99] [Sciences de la santé humaine] ,Cognitive training ,Older adults ,Cognitive Neuroscience ,Working memory ,Neuroplasticity ,Reasoning ,Multidisciplinary, general & others [D99] [Human health sciences] ,tDCS - Abstract
Background: Transcranial direct current stimulation (tDCS) has been employed to boost working memory training (WMT) effects. Nevertheless, there is limited evidence on the efficacy of this combination in older adults. The present study is aimed to assess the delayed transfer effects of tDCS coupled with WMT in older adults in a 15-day follow-up. We explored if general cognitive ability, age, and educational level predicted the effects. Methods: In this single-center, double-blind randomized sham-controlled experiment, 54 older adults were randomized into three groups: anodal-tDCS (atDCS)CWMT, shamtDCS (stDCS)CWMT, and double-sham. Five sessions of tDCS (2 mA) were applied over the left dorsolateral prefrontal cortex (DLPFC). Far transfer was measured by Raven’s Advanced Progressive Matrices (RAPM), while the near transfer effects were assessed through Digit Span. A frequentist linear mixed model (LMM) was complemented by a Bayesian approach in data analysis. Results: Working memory training improved dual n-back performance in both groups submitted to this intervention but only the group that received atDCSCWMT displayed a significant improvement from pretest to follow-up in transfer measures of reasoning (RAPM) and short-term memory (forward Digit Span). Near transfer improvements predicted gains in far transfer, demonstrating that the far transfer is due to an improvement in the trained construct of working memory. Age, formal education, and vocabulary score seem to predict the gains in reasoning. However, Bayesian results do not provide substantial evidence to support this claim.Conclusion: This study will help to consolidate the incipient but auspicious field of cognitive training coupled with tDCS in healthy older adults. Our findings demonstrated that atDCS may potentialize WMT by promoting transfer effects in short-term memory and reasoning in older adults, which are observed especially at follow-up. This study was funded by BIAL Foundation (#286/16), Portuguese Foundation for Science and Technology (FCT) (Doctoral Grants SFRH/BD/80965/2011, awarded to ACT-S, and PD/BD/105964/2014, awarded to DRP). This work was conducted at the Psychology Research Centre (PSI/01662), supported by the FCT and the Portuguese Ministry of Science, Technology and Higher Education (UID/PSI/01662/2019), through the national funds (PIDDAC). AS and DRP were supported by FCT (POC-01-0145-FEDER-028682 and NORTE- 01-0145-FEDER-032152). CM was partially supported by CMUP, which was financed by national funds through the Portuguese Foundation for Science and Technology (FCT), under the project with reference [UIDB/00144/2020]. SC was supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Science, through national funds and co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653) and by the FCT grant PTDC/PSI-ESP/29701/2017 and the individual Grant IF/00091/2015. JL was funded through the grant PTDC/PSIESP/30280/2017. published
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- 2022
24. Digitalized transcranial electrical stimulation: A consensus statement
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Andre R Brunoni, Hamed Ekhtiari, Andrea Antal, Paradee Auvichayapat, Chris Baeken, Isabela M. Benseñor, Marom Bikson, Paulo Boggio, Barbara Borroni, Filippo Brighina, Jerome Brunelin, Sandra Carvalho, Wolnei Caumo, Patrick Ciechanski, Leigh Charvet, Vincent P. Clark, Roi Cohen Kadosh, Maria Cotelli, Abhishek Datta, Zhi-De Deng, Rudi De Raedt, Dirk De Ridder, Paul B. Fitzgerald, Agnes Floel, Flavio Frohlich, Mark S. George, Peyman Ghobadi-Azbari, Stephan Goerigk, Roy H. Hamilton, Shapour J. Jaberzadeh, Kate Hoy, Dawson J. Kidgell, Arash Khojasteh Zonoozi, Adam Kirton, Steven Laureys, Michal Lavidor, Kiwon Lee, Jorge Leite, Sarah H. Lisanby, Colleen Loo, Donel M. Martin, Carlo Miniussi, Marine Mondino, Katia Monte-Silva, Leon Morales-Quezada, Michael A. Nitsche, Alexandre H. Okano, Claudia S. Oliveira, Balder Onarheim, Kevin Pacheco-Barrios, Frank Padberg, Ester M. Nakamura-Palacios, Ulrich Palm, Walter Paulus, Christian Plewnia, Alberto Priori, Tarek K. Rajji, Lais B. Razza, Erik M. Rehn, Giulio Ruffini, Klaus Schellhorn, Mehran Zare-Bidoky, Marcel Simis, Pawel Skorupinski, Paulo Suen, Aurore Thibaut, Leandro C.L. Valiengo, Marie-Anne Vanderhasselt, Sven Vanneste, Ganesan Venkatasubramanian, Ines R. Violante, Anna Wexler, Adam J. Woods, Felipe Fregni, Brain, Body and Cognition, Clinical sciences, Neuroprotection & Neuromodulation, Psychiatry, Brunoni, Andre R, Ekhtiari, Hamed, Antal, Andrea, Auvichayapat, Paradee, Baeken, Chri, Benseñor, Isabela M, Bikson, Marom, Boggio, Paulo, Borroni, Barbara, Brighina, Filippo, Brunelin, Jerome, Carvalho, Sandra, Caumo, Wolnei, Ciechanski, Patrick, Charvet, Leigh, Clark, Vincent P, Cohen Kadosh, Roi, Cotelli, Maria, Datta, Abhishek, Deng, Zhi-De, De Raedt, Rudi, De Ridder, Dirk, Fitzgerald, Paul B, Floel, Agne, Frohlich, Flavio, George, Mark S, Ghobadi-Azbari, Peyman, Goerigk, Stephan, Hamilton, Roy H, Jaberzadeh, Shapour J, Hoy, Kate, Kidgell, Dawson J, Zonoozi, Arash Khojasteh, Kirton, Adam, Laureys, Steven, Lavidor, Michal, Lee, Kiwon, Leite, Jorge, Lisanby, Sarah H, Loo, Colleen, Martin, Donel M, Miniussi, Carlo, Mondino, Marine, Monte-Silva, Katia, Morales-Quezada, Leon, Nitsche, Michael A, Okano, Alexandre H, Oliveira, Claudia S, Onarheim, Balder, Pacheco-Barrios, Kevin, Padberg, Frank, Nakamura-Palacios, Ester M, Palm, Ulrich, Paulus, Walter, Plewnia, Christian, Priori, Alberto, Rajji, Tarek K, Razza, Lais B, Rehn, Erik M, Ruffini, Giulio, Schellhorn, Klau, Zare-Bidoky, Mehran, Simis, Marcel, Skorupinski, Pawel, Suen, Paulo, Thibaut, Aurore, Valiengo, Leandro C L, Vanderhasselt, Marie-Anne, Vanneste, Sven, Venkatasubramanian, Ganesan, Violante, Ines R, Wexler, Anna, Woods, Adam J, and Fregni, Felipe
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Mobile Health ,Consensus ,Settore M-PSI/02 - PSICOBIOLOGIA E PSICOLOGIA FISIOLOGICA ,Clinical psychology ,methods [Transcranial Direct Current Stimulation] ,Transcranial Direct Current Stimulation ,Sensory Systems ,Electric Stimulation ,Telemedicine ,Psychiatry and Mental health ,Neurology ,Physiology (medical) ,Delphi panel ,Systematic review ,Humans ,Non-invasive neuromodulation ,Neurology (clinical) ,ddc:610 ,Digital health - Abstract
Objective: Although relatively costly and non-scalable, non-invasive neuromodulation interventions are treatment alternatives for neuropsychiatric disorders. The recent developments of highly-deployable transcranial electric stimulation (tES) systems, combined with mobile-Health technologies, could be incorporated in digital trials to overcome methodological barriers and increase equity of access. The study aims are to discuss the implementation of tES digital trials by performing a systematic scoping review and strategic process mapping, evaluate methodological aspects of tES digital trial designs, and provide Delphi-based recommendations for implementing digital trials using tES.Methods: We convened 61 highly-productive specialists and contacted 8 tES companies to assess 71 issues related to tES digitalization readiness, and processes, barriers, advantages, and opportunities for implementing tES digital trials. Delphi-based recommendations (>60% agreement) were provided.Results: The main strengths/opportunities of tES were: (i) non-pharmacological nature (92% of agreement), safety of these techniques (80%), affordability (88%), and potential scalability (78%). As for weaknesses/threats, we listed insufficient supervision (76%) and unclear regulatory status (69%). Many issues related to methodological biases did not reach consensus. Device appraisal showed moderate digitalization readiness, with high safety and potential for trial implementation, but low connectivity.Conclusions: Panelists recognized the potential of tES for scalability, generalizability, and leverage of digital trials processes; with no consensus about aspects regarding methodological biases. Significance: We further propose and discuss a conceptual framework for exploiting shared aspects between mobile-Health tES technologies with digital trials methodology to drive future efforts for digitizing tES trials. (C) 2022 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.
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- 2022
25. Transcranial Direct Current Stimulation Decreases P3 Amplitude and Inherent Delta Activity During a Waiting Impulsivity Paradigm
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Augusto J. Mendes, Santiago Galdo-Álvarez, Alberto Lema, Sandra Carvalho, and Jorge Leite
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Background One of the main features of addictive behaviors is the inability to wait for an action, that is, the waiting impulsivity. It has been suggested that potential therapeutic tools for addiction, such as transcranial Direct Current Stimulation (tDCS), might focus on this inability. Nonetheless, whereas there is consensus about the role of prefrontal cortex on impulsivity behavior, the effects of tDCS in waiting impulsivity and underlying electrophysiological (EEG) markers are still not clear. Objective The study aimed the neuromodulation of right inferior frontal gyrus during a task designed to elicit premature responses, while EEG markers important in reward anticipation (i.e., cue and target-P3 and underlying delta/theta activity) were studied. Methods Forty healthy subjects participated in two experimental sessions, where they received active and sham tDCS while performing a premature responding task and the EEG was recorded. At next, participants performed two control tasks to evaluate transfer effects for delay discounting and motor inhibition abilities. Results Active tDCS decreased amplitude in cue-P3, target-P3, and delta activity during target-P3. On the other hand, active tDCS increased the discounting of future rewards in small values in comparison with sham, while no tDCS effects were found in motor inhibition. Conclusion These findings suggest tDCS-induced modulation of the P3 component and underlying oscillatory activity during waiting impulsivity. Moreover, these changes were associated with differences in the discounting of future rewards. Thus, the current study suggests the usefulness of tDCS in modulating impulsive processes and the relationship between P3, the inherent delta activity, and reward processing.
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- 2022
26. Digitizing Non-Invasive Neuromodulation Trials: Scoping Review, Process Mapping, and Recommendations from a Delphi Panel
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Andre R Brunoni, Hamed Ekhtiari, Andrea Antal, Paradee Auvichayapat, Chris Baeken, Isabela M. Benseñor, Marom Bikson, Paulo Boggio, Barbara Borroni, Filippo Brighina, Jerome Brunelin, Sandra Carvalho, Wolnei Caumo, Patrick Ciechanski, Leigh Charvet, Vincent P. Clark, Roi Cohen Kadosh, Maria Cotelli, Abhishek Datta, Zhi-De Deng, Rudi De Raedt, Dirk De Ridder, Paul B. Fitzgerald, Agnes Floel, Flavio Frohlich, Mark S. George, Peyman Ghobadi-Azbari, Stephan Goerigk, Roy H. Hamilton, Shapour J. Jaberzadeh, Kate Hoy, Dawson J. Kidgell, Arash Khojasteh Zonoozi, Adam Kirton, Steven Laureys, Michal Lavidor, Kiwon Lee, Jorge Leite, Sarah H. Lisanby, Colleen Loo, Donel M. Martin, Carlo Miniussi, Marine Mondino, Katia Monte-Silva, Leon Morales-Quezada, Michael A. Nitsche, Alexandre H. Okano, Claudia S. Oliveira, Balder Onarheim, Kevin Pacheco-Barrios, Frank Padberg, Ester M Nakamura-Palacios, Ulrich Palm, Walter Paulus, Christian Plewnia, Alberto Priori, Tarek K. Rajji, Lais B. Razza, Erik M. Rehn, Giulio Ruffini, Klaus Schellhorn, Mehran Zare-Bidoky, Marcel Simis, Pawel Skorupinski, Paulo Suen, Aurore Thibaut, Leandro C. L. Valiengo, Marie-Anne Vanderhasselt, Sven Vanneste, Ganesan Venkatasubramanian, Ines R. Violante, Anna Wexler, Adam J. Woods, and Felipe Fregni
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Abstract
Although relatively costly and non-scalable, non-invasive neuromodulation interventions are treatment alternatives for neuropsychiatric disorders. The recent developments of highly-deployable transcranial electric stimulation (tES) systems, combined with mobile-Health technologies, could be incorporated in digital trials to overcome methodological barriers and increase equity of access. We convened 61 highly-productive specialists and contacted 8 tES companies to assess 71 issues related to tES digitalization readiness, and processes, barriers, advantages, and opportunities for implementing tES digital trials. Delphi-based recommendations (>60% agreement) were provided. Device appraisal showed moderate digitalization readiness, with high safety and the possibility of trial implementation, but low connectivity. Panelists recognized the potential of tES for scalability, generalizability, and leverage of digital trials processes; although they reached no consensus about aspects regarding methodological biases. We further propose and discuss a conceptual framework for exploiting shared aspects between mobile-Health tES technologies with digital trials methodology to drive future efforts for digitizing tES trials.Graphical Abstract. Consensus Roadmap(A) Recruitment process. The study procedure started with defining the components of the research problem by the core research team. After defining the problems, two different sets of participants (the steering committee (SC) including key leaders of the field identified by the core team and the expert panel (EP) as a more diverse group of experts identified based on the number of publications based on a systematic review) were identified and were invited to participate in a Delphi study. The study facilitators (first and last authors) led the communications with the SC to design the initial questionnaire through an iterative approach. (B) Evidence synthesis: To collect the available evidence, companies producing portable tES (ptES) devices were contacted, based on the companies suggested by the SC and EP to provide details about the available devices. For mapping methodological processes of digitizing tES trials, two distinct strategies were performed and embedded into the questionnaire, namely SIPOC (Suppliers, Inputs, Process, Outputs, and Customer) and SWOT (Strengths, Weaknesses, Opportunities, and Threats) assessment were performed and embedded into the questionnaire. (C) Consensus development: In the next phase, the questionnaire was validated and finalized via collecting and summarizing opinions. Afterward, the SC and EP responded to the final questionnaire, and results were analyzed providing a list of recommendations for running tES digital trials based on a pre-registered consensus threshold.
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- 2022
27. Tribological performance of hybrid surfaces: dimple-shaped anodized Al alloy surfaces coated with WS-CF sputtered thin films
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Sandra Carvalho, Albano Cavaleiro, and S.P. Rodrigues
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0209 industrial biotechnology ,Materials science ,Mechanical Engineering ,02 engineering and technology ,Sputter deposition ,Tribology ,Industrial and Manufacturing Engineering ,Surface energy ,Computer Science Applications ,Contact angle ,020901 industrial engineering & automation ,Control and Systems Engineering ,Lubrication ,Surface roughness ,Wetting ,Thin film ,Composite material ,Software - Abstract
This work is on the study of the synergetic effect of anodized Al alloy surfaces, with thin tungsten disulphide films alloyed with carbon and fluorine (WS-CF) deposited by magnetron sputtering. The surface roughness and surface chemistry were changed to tune the surface wettability and improve the frictional behaviour of the hybrid surfaces. The SEM analysis of these surfaces showed that, although the film growth has led to the progressive pore narrowing, pores were still visible after deposition of an ~ 200 nm thick film. Even though the film deposition has induced the surface smoothening, the surface free energy (SFE) of the hybrid surfaces was not substantially altered, when compared to bare anodized surface with large dimple (LD). Accordingly, the contact angles measured with water (WCA) and α-bromonaphthalene (OCA) on the hybrid surfaces suggested that the film surface chemistry was the main responsible for the wettability results, having the bottom dimple-shaped surface roughness just a low effect. LD surface coated with pure WS2 coating (LD + WS2) showed a remarkable high hydrophobicity combined with a high oleophilicity. Pin-on-disc testing carried out at room temperature in dry conditions showed much lower coefficient of friction (COF) values for the coated samples (hybrid surfaces), comparatively to uncoated ones. Furthermore, the friction performance of the hybrid surfaces was better for the F-alloyed thin film (sample named as WS-CF5 and having 9.5 at% of F) than for the WS2 film. In lubricated testing with a polyalphaolefin oil (PAO-8), the soft uncoated surfaces presented lower COF values, since the rapid smoothening of the contact surface turned the lubrication regime from mixed to hydrodynamic-like. For the LD surfaces coated with the F-alloyed WS film (named as LD + WS-CF5), the higher hardness of WS-CF5 was responsible for keeping the lubrication regime in partial lubricated conditions, leading to higher initial COF. Afterwards, a WS2-based tribolayer is formed in the solid-solid contacts which, together with the progressive film smoothening, change the lubricated regime toward hydrodynamic. Therefore, the friction of LD + WS-CF5 was reduced with the elapsed time and approached the one of the uncoated samples (LD). Concluding, both these hybrid surfaces can have a role on oil-water separation processes, self-cleaning of building outdoors or on microfluidic and printing applications.
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- 2020
28. Stirring and mixing in ethylic biodiesel production
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Pollyanna Vanessa dos Santos Lins, Simoni M.P. Meneghetti, Sandra Carvalho, João Inácio Soletti, Wagner Roberto de Oliveira Pimentel, Lucas Meili, and Amanda Santana Peiter
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Biodiesel ,Multidisciplinary ,Materials science ,020209 energy ,Mixing (process engineering) ,Baffle ,02 engineering and technology ,Pulp and paper industry ,Turbine ,Catalysis ,Impeller ,Yield (chemistry) ,Biodiesel production ,0202 electrical engineering, electronic engineering, information engineering ,lcsh:Science (General) ,lcsh:Q1-390 - Abstract
This study aimed to analyze the influence of stirring and mixing on the production of soybean biodiesel. It was verified the influence of the baffle, different stirring speeds and two types of impellers (turbine and blade). The experiments were conducted by full experimental design 23 with the following fixed parameters: temperature (70 °C), oil/ethanol molar ratio (1/10), catalyst amount (1.5%), and reaction time (30 min). The independent variables were impeller type (turbine or blade), baffle (presence or absence), and stirring speed (150 or 350 rpm). Chromatographic analyses helped to determine the yield of biodiesel production at different operating times. The optimized parameters turbine impeller, absence of baffle, and stirring speed of 350 rpm provided high biodiesel yields within the first minutes of reaction. The analysis of the effect over time allows to verify in which period the variables had more influence on the biodiesel production and in which time there is no increase of the yield. Keywords: Optimization, Stirring, Biofuels, Production
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- 2020
29. Viability Study of Machine Learning-Based Prediction of COVID-19 Pandemic Impact in Obsessive-Compulsive Disorder Patients
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María Tubío-Fungueiriño, Eva Cernadas, Óscar F. Gonçalves, Cinto Segalas, Sara Bertolín, Lorea Mar-Barrutia, Eva Real, Manuel Fernández-Delgado, Jose M. Menchón, Sandra Carvalho, Pino Alonso, Angel Carracedo, and Montse Fernández-Prieto
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OCD ,Biomedical Engineering ,Neuroscience (miscellaneous) ,COVID-19 ,Neurosciences. Biological psychiatry. Neuropsychiatry ,Classification ,Regression ,Computer Science Applications ,obsessive-compulsive disorder ,machine learning ,classification ,Y-BOCS ,Aprenentatge automàtic ,Machine learning ,Obsessive-compulsive disorder ,RC321-571 - Abstract
Background: Machine learning modeling can provide valuable support in different areas of mental health, because it enables to make rapid predictions and therefore support the decision making, based on valuable data. However, few studies have applied this method to predict symptoms’ worsening, based on sociodemographic, contextual, and clinical data. Thus, we applied machine learning techniques to identify predictors of symptomatologic changes in a Spanish cohort of OCD patients during the initial phase of the COVID-19 pandemic. Methods: 127 OCD patients were assessed using the Yale–Brown Obsessive-Compulsive Scale (Y-BOCS) and a structured clinical interview during the COVID-19 pandemic. Machine learning models for classification (LDA and SVM) and regression (linear regression and SVR) were constructed to predict each symptom based on patient’s sociodemographic, clinical and contextual information. Results: A Y-BOCS score prediction model was generated with 100% reliability at a score threshold of ± 6. Reliability of 100% was reached for obsessions and/or compulsions related to COVID-19. Symptoms of anxiety and depression were predicted with less reliability (correlation R of 0.58 and 0.68, respectively). The suicidal thoughts are predicted with a sensitivity of 79% and specificity of 88%. The best results are achieved by SVM and SVR. Conclusion: Our findings reveal that sociodemographic and clinical data can be used to predict changes in OCD symptomatology. Machine learning may be valuable tool for helping clinicians to rapidly identify patients at higher risk and therefore provide optimized care, especially in future pandemics. However, further validation of these models is required to ensure greater reliability of the algorithms for clinical implementation to specific objectives of interest. Sandra Carvalho receives scholarship and support from the Portuguese Foundation for Science and Technology (FCT), co-funded through COMPETE 2020 – PO Competitividade e Internacionalização/Portugal 2020/European Union, FEDER (Fundos Europeus Estruturais e de Investimento – FEEI) under the number:PTDC/PSI-ESP/29701/2017. published
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- 2022
30. Corrosion Behavior of Biofunctionalized Ta Surfaces Under Artificial Saliva
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Catarina Rebelo, José David Castro, Cristiana F. A. Alves, Luísa Fialho, and Sandra Carvalho
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- 2022
31. Antimicrobial Polymeric Surfaces Using Embedded Silver Nanoparticles
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Pooja Sharma, Luisa Fialho, Nuno Miguel Figueiredo, Ricardo Serra, Albano Cavaleiro, Sandra Carvalho, and Universidade do Minho
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Microbiology (medical) ,Science & Technology ,Infectious Diseases ,Polycarbonate ,Ciências Naturais::Ciências Físicas ,Thermal embedding ,Glass transition temperature ,Pharmacology (medical) ,Silver nanoparticles ,Antimicrobial activity ,General Pharmacology, Toxicology and Pharmaceutics ,Biochemistry ,Microbiology - Abstract
Pathogens (disease-causing microorganisms) can survive up to a few days on surfaces and can propagate through surfaces in high percentages, and thus, these surfaces turn into a primary source of pathogen transmission. To prevent and mitigate pathogen transmission, antimicrobial surfaces seem to be a promising option that can be prepared by using resilient, mass-produced polymers with partly embedded antimicrobial nanoparticles (NPs) with controlled size. In the present study, a 6 nm thick Ag nanolayer was sputter deposited on polycarbonate (PC) substrate and then thermally annealed, in a first step at 120 °C (temperature below Tg) for two hours, for promoting NP diffusion and growth, and in a second step at 180 °C (temperature above Tg) for 22 h, for promoting thermal embedding of the NPs into the polymer surface. The variation in the height of NPs on the polymer surface with thermal annealing confirms the embedding of NPs. It was shown that the incorporation of silver nanoparticles (Ag NPs) had a great impact on the antibacterial capacity, as the Ag NP-embedded polymer surface presented an inhibition effect on the growth of Gram-positive and Gram-negative bacteria. The tested surface-engineering process of incorporating antimicrobial Ag NPs in a polymer surface is both cost-effective and highly scalable., This research was funded by CEMMPRE’s research and development unit project (UIDB/00285/2020) and Science DiabetICC Footwear with reference POCI-01-0247-FEDER-039784, supported by Portugal 2020. This research was supported by the COMPETE 2020 Portuguese and European Union initiative through Project POCI-01-0247-FEDER-072607, R&D and the production of logos for the automotive industry. This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of Strategic Funding (co-financed via UIDB/00285/2020) and LA/P/0112/2020.
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- 2023
32. Tribological solutions for engine piston ring surfaces: an overview on the materials and manufacturing
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Rita Ferreira, Óscar Carvalho, Sandra Carvalho, Luís Sobral, Jorge Martins, and Filipe Samuel Silva
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010302 applied physics ,0209 industrial biotechnology ,Materials science ,Mechanical Engineering ,Mechanical engineering ,02 engineering and technology ,Tribology ,Ring (chemistry) ,01 natural sciences ,Industrial and Manufacturing Engineering ,law.invention ,Piston ,020901 industrial engineering & automation ,Mechanics of Materials ,law ,0103 physical sciences ,General Materials Science ,Piston ring - Abstract
This paper exhibits an outline of the piston rings operational characteristics and consequently, of their main functional challenges. The basic geometrical shapes, materials and manufacturi...
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- 2019
33. Marketing de relacionamento no mercado empresarial de prestação de serviços: um estudo de caso em uma empresa de telefonia fixa
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Sandra Carvalho dos Santos, Geraldo Luciano Toledo, Jorge Americo Silva Machado, and Dilson Gabriel dos Santos
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O objetivo da presente dissertação é contribuir para o entendimento do conceito de marketing de relacionamento no mercado empresarial. Para alcançar esse objetivo, foi realizada uma vasta revisão bibliográfica sobre o assunto e conduzido um estudo de caso único em uma pesquisa qualitativa do tipo exploratória. Para o estudo de caso, foi selecionado o setor de telecomunicações, pela sua posição estratégica atual e pela alta competitividade existente neste setor brasileiro após a sua privatização, representado pela líder do mercado brasileiro de telefonia fixa e uma das maiores empresas do país - a Telemar. Partindo-se dos conceitos teóricos pesquisados na bibliografia de referência, foram definidos os pressupostos conceituais do marketing de relacionamento que melhor se aplicam a uma empresa de serviços que atua no B2B. Em seguida, utilizando-se do método de estudo de caso, esses conceitos foram investigados na prática junto à empresa de telefonia objeto desse estudo. Dessa forma, avaliando-se comparativamente os aspectos teóricos e práticos do marketing de relacionamento, pode-se identificar o nível atual de entendimento e aplicação desse conceito pela empresa estudada. Os resultados da pesquisa indicaram que a empresa entende parcialmente o conceito de marketing de relacionamento, atendendo a vários dos pressupostos conceituais definidos. Dentre aos conceitos ainda não aplicados pela empresa estudada, destaca-se a adoção de utilização da lealdade e lucratividade do cliente como principal medida de medidas para avaliação do desempenho das estratégias de relacionamento implantadas e a utilização da lealdade e lucratividade do cliente como principal medida de desempenho da organização. Como contribuição final, esse trabalho apresenta uma profunda e atual pesquisa bibliográfica envolvendo conceitos de marketing estratégico, marketing empresarial e marketing de serviços; identifica os pressupostos conceituais relacionados às estratégias de marketing de relacionamento em uma empresa de serviços que atua no mercado B2B; e comprova a carência de medidas de desempenho para avaliar as ações de marketing de relacionamento das empresas. The aim of this dissertation is to contribute to the understanding of relationship marketing concept in the business market. To reach this objective, a vast bibliographic research was made and a case study was realized. The chosen sector was the telecommunication since it has a present strategic position and competitiveness. For this particular case study, it was selected Telemar which is the Brazilian telecommunication market leader. First, from the theory, the relationship marketing concepts that could be applied to B2B Service industry were defined. Then, these concepts were investigated at Telemar using the case study research method. Finally, the theoretical and practical issues were analyzed and compared in order to identify how Telemar understand and apply the relationship marketing. It can be said from the research results that Telemar understand and apply most of the conceptual issues investigated. However, it does not have any tool either to evaluate the relationship strategy efficiency nor to use customers loyalty and profitability to measure the organization performance. The final contribution of this study is a wide and up-to-date bibliographic research on strategic marketing, business marketing and service marketing. Moreover, it is observed not only the identification of the conceptual issues of relationship marketing in B2B service organizations, but also the confirmation that it is necessary to implement some performance evaluation system to monitoring and measuring of the relationship marketing strategies.
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- 2021
34. Co-Expression of T- and B-Cell Markers in a Canine Intestinal Lymphoma: A Case Report
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Pâmela Cristina Lopes Gurgel Valente, Maria Conceição Peleteiro, Sandra Carvalho, Rodolfo Oliveira Leal, Constança Pomba, António Duarte, and Jorge Correia
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General Veterinary ,Animal Science and Zoology - Abstract
An 8-year-old female neutered Labrador retriever was presented for a second opinion consultation due to vomiting and lethargy, having failed to respond to symptomatic therapy. Blood analysis revealed hyperbilirubinemia and hypoalbuminemia, associated with hypocobalaminemia. An abdominal ultrasound identified diffused bowel thickening and hypoechoic hepatomegaly. An ultrasound-guided liver fine-needle aspiration was performed for cytology and also for cell block immunocytochemistry. Gastric and duodenal biopsies were collected by gastroduodenoscopy. Liver cytology showed numerous lymphocytes, suggesting lymphoma at the hepatic infiltration stage, and immunocytochemistry in the cell block of the hepatic aspirate indicated co-expression of CD3 and CD20 in the lymphoid cells present. The histopathology of gastric and duodenal biopsies supported the hypothesis of gastrointestinal lymphoma due to heavy lymphoid infiltration of the gastric epithelium and intestinal mucosa, including the villi. Concurrent immunohistochemistry was performed using CD3, CD20, PAX5, and CD79αcy antibodies. Immunomarking was positive for CD3 and CD20, which overlapped populations of lymphoid cells, and was negative for all other antibodies. In the clonality test, lymphocyte co-expression of CD3 and CD20 was confirmed by monoclonal rearrangement of T-cell gamma receptors. The final diagnosis was type 2 enteropathy-associated T-cell lymphoma with hepatic infiltration. Co-expression was examined in conjunction with the PARR result in the presence of T-cell monoclonal rearrangement.
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- 2022
35. Identification of a Proteasome-Targeting Arylsulfonamide with Potential for the Treatment of Chagas' Disease
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Stephen Patterson, Marta Lopes Lima, Lorna MacLean, Susan Wyllie, David Horn, Lindsay B. Tulloch, Sonia Moniz, Ian H. Gilbert, Richard J. Wall, Victoriano Corpas-López, Fabio Zuccotto, Rachel Milne, Eva Rico, Carmine Marco Morgillo, Leah S. Torrie, and Sandra Carvalho
- Subjects
Chagas’ disease ,Proteasome Endopeptidase Complex ,Phenotypic screening ,Trypanosoma cruzi ,Malic enzyme ,drug target ,malic enzyme ,parasitic diseases ,Drug Discovery ,medicine ,Humans ,Pharmacology (medical) ,Chagas Disease ,Mode of action ,Mechanisms of Action: Physiological Effects ,Pharmacology ,biology ,Drug discovery ,Chemistry ,biology.organism_classification ,Infectious Diseases ,proteasome ,Proteasome ,Mechanism of action ,Biochemistry ,medicine.symptom ,Pharmacophore ,Proteasome Inhibitors ,mechanism of action - Abstract
Phenotypic screening identified an arylsulfonamide compound with activity against Trypanosoma cruzi, the causative agent of Chagas’ disease. Comprehensive mode of action studies revealed that this compound primarily targets the T. cruzi proteasome, binding at the interface between β4 and β5 subunits that catalyze chymotrypsin-like activity. A mutation in the β5 subunit of the proteasome was associated with resistance to compound 1, while overexpression of this mutated subunit also reduced susceptibility to compound 1. Further genetically engineered and in vitro-selected clones resistant to proteasome inhibitors known to bind at the β4/β5 interface were cross-resistant to compound 1. Ubiquitinated proteins were additionally found to accumulate in compound 1-treated epimastigotes. Finally, thermal proteome profiling identified malic enzyme as a secondary target of compound 1, although malic enzyme inhibition was not found to drive potency. These studies identify a novel pharmacophore capable of inhibiting the T. cruzi proteasome that may be exploitable for anti-chagasic drug discovery.
- Published
- 2021
36. FELINE: Finite element solver for hydrodynamic lubrication problems using the inexact Newton method
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Alexandre Silva, Veniero Lenzi, Albano Cavaleiro, Sandra Carvalho, Luís Marques, and Universidade do Minho
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Finite element method ,Science & Technology ,Ciências Naturais::Ciências Físicas ,Hardware and Architecture ,Inexact Newton method ,General Physics and Astronomy ,Indústria, inovação e infraestruturas ,Hydrodynamic lubrication - Abstract
In this work we present FELINE, a C++ solver of the Reynolds equation for treating hydrodynamic lubrication problems. To correctly describe cavitation regions, FELINE implements the inexact Newton iteration (INE) algorithm within a finite element method (FEM) framework. The solver was tested and validated against known cases in literature and industrially relevant cases of dimpled textures. Furthermore, we provide a benchmark for a complex dimpled texture case to evaluate the performance and robustness of the implementation. FELINE performs very fast when compared with existing implementations and shows a great degree of stability, while providing physically correct solutions thanks to the INE algorithm., This work was supported by the Portuguese Foundation for Science and Technology (in the framework of the Strategic Funding UIDB/04650/2020 project PTDC/EME-SIS/30446/2017 and Advanced Computing Project CPCA/A2/ 4513/2020, awarded by FCT I.P., for accessing MACC-BOB HPC resources.
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- 2022
37. Physical Vapor Deposition Technology in Personal Protective Equipment Production: Improved Antibacterial and Hydrophobic Character of Textiles
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José Antunes, Karim Matos, Isabel Carvalho, Sandra Carvalho, Fábio Ferreira, Sandra M. A. Cruz, and Universidade do Minho
- Subjects
Antibacterial ,Fabric ,Science & Technology ,Personal protective equipment ,DLC ,Materials Chemistry ,Sputtering ,COVID-19 ,Surfaces and Interfaces ,personal protective equipment ,sputtering ,fabric ,antibacterial ,Surfaces, Coatings and Films - Abstract
Personal protective equipment (PPE) has been adapted as biological threats have emerged, such as increasingly drug-resistant bacteria and the emergence of new viruses such as COVID-19. PPE must be increasingly resilient to prevent the proliferation of pathogens, but using sustainable raw materials and environmentally friendly technologies. The aim of this study is to show a new way of modifying the surface of various types of fabrics to enable their efficient use as PPE. The Ag/DLC coating was successfully deposited by sputtering onto several types of textiles using different chemical compositions of Ag/DLC (0, 8, 10, and 12Ag). As a crucial parameter, wettability was evaluated, showing that silver addition increases the hydrophobicity character of the coated fabrics, namely in cotton, changing from hydrophilic to hydrophobic. Antibacterial activity and cytotoxicity were evaluated on all coatings, revealing that they are efficient in eliminating the spread of bacteria (Staphylococcus aureus and Klebsiella pneumoniae) and pose no risk to the human body. The results presented here are promising in protecting healthcare workers, with the next steps being to study the efficiency of these coatings against viruses. In addition, this study reveals an opportunity to use sustainable fabrics, such as cotton, with high efficiency in protection against pathogens, instead of synthetic fiber textiles., This research is sponsored by national funds through FCT-Fundacao para a Ciencia e a Tecnologia, under the project UIDB/00285/2020, LA/P/0112/2020, UIDB/04469/2020 and LA/P/0029/2020. This research was also sponsored by FEDER funds through the program Centro 2020-Programa Operacional Regional do Centro under project CENTRO-01-0145-FEDER-181221, ActiveStent., info:eu-repo/semantics/publishedVersion
- Published
- 2022
38. Tribological testing of leather surface coated with sputter-deposited Ti-Ag-O films
- Author
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Anna Maria Hofer-Roblyek, Marisa Rebelo de Figueiredo, Christian Mitterer, Robert Franz, Sandra Carvalho, Carmen Gaidau, and Isabel Carvalho
- Subjects
chemistry.chemical_classification ,Materials science ,Scanning electron microscope ,Mechanical Engineering ,Abrasive ,Nanoparticle ,02 engineering and technology ,Surfaces and Interfaces ,Polymer ,Tribology ,021001 nanoscience & nanotechnology ,Surfaces, Coatings and Films ,Human health ,020303 mechanical engineering & transports ,0203 mechanical engineering ,chemistry ,Mechanics of Materials ,Sputtering ,Adhesive ,Composite material ,0210 nano-technology - Abstract
New leather treatment processes involving nanoparticles require new testing methods and procedures to evaluate their impact on human health. In the current work, the tribological properties of goat leather surfaces with sputter deposited Ti-Ag-O films were analyzed. A set of different polymer counter bodies was used to establish different tribological contact situations. A detailed analysis of the worn surfaces by scanning electron microscopy revealed details about the wear mechanisms ranging from abrasive to adhesive depending on the friction. Further, information about the formation of wear debris particles from the Ti-Ag-O films was obtained, in particular whether or not these particles were transferred to the counter body. The performed tests exemplify a possible testing procedure for leather treated with nanoparticles.
- Published
- 2019
39. TiSiN(Ag) films deposited by HiPIMS working in DOMS mode: Effect of Ag content on structure, mechanical properties and thermal stability
- Author
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D. Cavaleiro, F. Fernandes, Sandra Carvalho, and Albano Cavaleiro
- Subjects
Materials science ,Annealing (metallurgy) ,General Physics and Astronomy ,chemistry.chemical_element ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,engineering.material ,Sputter deposition ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Microstructure ,01 natural sciences ,Grain size ,0104 chemical sciences ,Surfaces, Coatings and Films ,Coating ,chemistry ,Chemical engineering ,engineering ,Crystallite ,High-power impulse magnetron sputtering ,0210 nano-technology ,Tin - Abstract
TiSiN(Ag) coatings with Ag contents ranging from 0 to 29 at.% were designed as promising materials to allow long term solid lubrication during dry machining operations. Here, we report the influence of Ag additions on the properties of TiSiN(Ag) films deposited by high power impulse magnetron sputtering- HiPIMS, working in deep oscillation magnetron sputtering mode – DOMS. Introduction of silver pellets on the target progressively increases the Ag concentration on the films, influencing the deposition rate, structure and morphology of the films. All the coatings display crystalline peaks assigned to a TiN fcc NaCl type structure. Ag additions to the reference TiSiN film, significantly broadens the TiN diffraction peaks and abruptly decreases the grain size of the TiN crystallites from 24 nm to 11–7 nm. Grain size was then found to be independent of the silver content on the films. Hardness and Young's modulus of the coatings decreased with increasing Ag additions mainly due to the increase of this soft phase on the microstructure. An increase in the peak power was observed when 6 at.% Ag was added which revealed a transition from a columnar to a very compact morphology, a decrease of the deposition rate and an increase of the lattice parameter for this coating. A reverse in the morphology is then perceived for the higher Ag concentration (29 at.%). Annealing treatment didn't present any significant changes in the structure/phase composition or mechanical properties of the coatings. Elemental maps and profiles allowed perceiving the formation of a very thin dual layer where a top Ag rich layer is formed due to the diffusion of silver from the Ag deficient TiSiN layer below.
- Published
- 2019
40. The impact of photocatalytic Ag/TiO2 and Ag/N-TiO2 nanoparticles on human keratinocytes and epithelial lung cells
- Author
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Catalina Mansilla Sánchez, Carmen Gaidau, Daniela Rebleanu, Sandra Carvalho, Geanina Voicu, Manuela Calin, Teresa C. Rojas, and Cristina Ana Constantinescu
- Subjects
0301 basic medicine ,chemistry.chemical_classification ,A549 cell ,Reactive oxygen species ,Programmed cell death ,Necrosis ,technology, industry, and agriculture ,respiratory system ,Toxicology ,Cell biology ,03 medical and health sciences ,HaCaT ,030104 developmental biology ,0302 clinical medicine ,chemistry ,Apoptosis ,medicine ,Cytotoxic T cell ,medicine.symptom ,Cytotoxicity ,030217 neurology & neurosurgery - Abstract
The potential human health risks following the exposure to inorganic nanoparticles (NPs) is a very important issue for their application in leather finishing industry. The aim of our study was to investigate the cytotoxic effect of silver (Ag)/titanium dioxide (TiO2) NPs on human cells. Photocatalytic NPs were prepared by electrochemical deposition of Ag on the surface of TiO2 and nitrogen (N)-TiO2 NPs and, subsequently, physico-chemical characterized. Then, a set of experiments have been performed to study the cytotoxicity and cell death mechanisms involved, the changes in cell morphology and the production of ROS induced in human keratinocytes (HaCaT) and human lung epithelial cells (A549) by exposure to NPs. Moreover, the changes in major signaling pathways and the inflammatory response induced by Ag/N-TiO2 NPs in A549 cells were investigated. The data showed that cell death by late apoptosis/necrosis is induced in cells as function of the dose and the type of NPs and is characterized by morphological changes and cytoskeletal disorganization and an increase in reactive oxygen species (ROS) production. The exposure of A549 cells to Ag/N-TiO2 NPs determine the activation of ERK1/2 MAP-kinase pathway and the release of pro-inflammatory mediators CXCL1, GM-CSF and MIF, known to be involved in the recruitment of circulating neutrophils and monocytes.
- Published
- 2019
41. Ag release from sputtered Ag/a:C nanocomposite films after immersion in pure water and NaCl solution
- Author
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Isabel Carvalho, Albano Cavaleiro, Marco A. Curado, Sandra Carvalho, and Carlos Palacio
- Subjects
010302 applied physics ,Materials science ,Nanocomposite ,Scanning electron microscope ,Doping ,Metals and Alloys ,Nanoparticle ,Biomaterial ,02 engineering and technology ,Surfaces and Interfaces ,Sputter deposition ,021001 nanoscience & nanotechnology ,01 natural sciences ,Silver nanoparticle ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,X-ray photoelectron spectroscopy ,Chemical engineering ,0103 physical sciences ,Materials Chemistry ,0210 nano-technology - Abstract
Diamond-like carbon (DLC) coatings doped with Ag nanoparticles are promising materials for several application, as, for example, a biomaterial. In addition to their numerous properties, when doped with silver, DLCs can acquire antibacterial properties. In this study, Ag/a:C films were deposited by unbalanced magnetron sputtering. The dimension and distribution of silver nanoparticles in the carbon matrix were characterized before and after immersion in different liquid environments, ultra-pure water and NaCl (0.9%). Inductively coupled plasma-optical emission spectroscopy was used to quantify the Ag ions released from the film. Based on the aspect of Ag nanoparticles on the films surface, suggested by atomic force microscopy analysis, scanning electron microscopy was performed to access the dimension and the distribution of the nanoparticles at the surface and, then, to calculate the mass of Ag in the film, before and after exposure to both liquids. Agglomeration and coalescence of the nanoparticles in the film surface were studied and information about the segregation from the bulk to the surface was achieved, also confirmed by X-ray photoelectron spectroscopy analysis.
- Published
- 2019
42. Adsorption of methylene blue on agroindustrial wastes: Experimental investigation and phenomenological modelling
- Author
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Marília Teodosio Costa, Pollyanna Vanessa dos Santos Lins, Eduardo Hiromitsu Tanabe, João Inácio Soletti, Guilherme Luiz Dotto, R. L. Almeida, Ana Karla de Souza Abud, Alessandro Erto, Lucas Meili, Lotfi Sellaoui, Sandra Carvalho, Meili, L., Lins, P. V. S., Costa, M. T., Almeida, R. L., Abud, A. K. S., Soletti, J. I., Dotto, G. L., Tanabe, E. H., Sellaoui, L., Carvalho, S. H. V., and Erto, A.
- Subjects
Materials science ,030303 biophysics ,Kinetics ,Biophysics ,Industrial Waste ,Agro-waste ,03 medical and health sciences ,chemistry.chemical_compound ,Adsorption ,Physisorption ,Monolayer ,Molecule ,Cellulose ,Molecular Biology ,0303 health sciences ,Statistical physic ,Biosorption ,Agriculture ,Saccharum ,Methylene Blue ,Biophysic ,Models, Chemical ,chemistry ,Chemical engineering ,Dyes removal ,Environmental Pollutants ,Bagasse ,Methylene blue - Abstract
In this work, agro-wastes coming from soursop (peel, seeds and pulp fiber) and sugarcane (bagasse) are used as low-cost biosorbents to remove methylene blue (MB) from aqueous media. Batch experiments are performed under different experimental conditions investigating the effects of biosorbent amount, dye concentration and stirring rate. The best results were found using soursop wastes for a MB concentration of 100 mg L−1, using 0.75 g of residue and a stirring rate of 110 rpm, removing a percentage above 90%. Theoretically, adsorption kinetic can be successfully described by the pseudo-second order model. Redlich-Peterson and Sips models are adopted to interpret the equilibrium adsorption of MB on sugarcane bagasse and soursop residue, respectively. Interestingly, the monolayer model with single energy derived by statistical physics theory is also applied for a deeper explanation of the adsorption mechanism of MB on both the adsorbents. The application of this model allows defining the adsorption geometry of the investigated adsorbate and provides important information about the interactions between the adsorbate and sorbents. In particular, the modelling analysis by statistical physics allows defining that the dye molecules are adsorbed in vertical position and the adsorption process is multi-molecular (i.e. n > 1). Finally, the estimation of adsorption energy suggested that MB adsorption on biosorbent is a physisorption process.
- Published
- 2019
43. Amplification-free SERS analysis of DNA mutation in cancer cells with single-base sensitivity
- Author
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Lei Wu, Marta Prado, Lorena Diéguez, Sara Abalde-Cela, Alejandro Garrido-Maestu, Joana Rafaela Lara Guerreiro, and Sandra Carvalho
- Subjects
Silver ,Microfluidics ,Metal Nanoparticles ,02 engineering and technology ,Spectrum Analysis, Raman ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,Proto-Oncogene Proteins p21(ras) ,chemistry.chemical_compound ,Molecular beacon ,Cell Line, Tumor ,Lab-On-A-Chip Devices ,medicine ,Humans ,General Materials Science ,Mutation ,Chemistry ,Point mutation ,DNA ,Surface-enhanced Raman spectroscopy ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Cancer cell ,Nucleic acid ,Biophysics ,Gold ,0210 nano-technology - Abstract
Accurate and sensitive identification of DNA mutations in tumor cells is critical to the diagnosis, prognosis and personalized therapy of cancer. Conventional polymerase chain reaction (PCR)-based methods are limited by the complicated amplification process. Herein, an amplification-free surface enhanced Raman spectroscopy (SERS) approach which directly detects point mutations in cancer cells has been proposed. A highly sensitive and uniform SERS substrate was fabricated using gold@silver core-shell nanorods, achieving an enhancement factor of 1.85 × 106. By combining the SERS-active nanosubstrate with molecular beacon probes, the limit of detection reached as low as 50 fM. To enable parallel analysis and automated operation, the SERS sensor was integrated into a microfluidic chip. This novel chip-based assay was able to differentiate between mutated and wild-type KRAS genes among a variety of other nucleic acids from cancer cells in 40 min. Owing to the simple operation and fast analysis, the SERS-based DNA assay chip could potentially provide insights into clinical cancer theranostics in an easy and inexpensive manner at the point of care.
- Published
- 2019
44. canto do movimento de mulheres trabalhadoras rurais (MMTR) de Inhambupe
- Author
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Sandra Carvalho CRUZ
- Abstract
Neste artigo, buscamos refletir sobre o potencial político, cultural e literário dos cantos do Movimento de Mulheres Trabalhadoras Rurais (MMTR) de Inhambupe, enquanto poética oral, produzida e divulgada por mulheres que trabalham na roça. Para tanto, lemos e relemos os cantos produzidos/entoados pelas integrantes do Movimento, lemos as performances das apresentações culturais realizadas no dia oito de março de 2018, analisamos muitas cenas e discursos flagrados nesse dia. Utilizamos como referencial teórico Edil Costa, Ari Lima, Hampaté Bâ, Espino Gonzalo, Jerusa Pires, Jonathan Culler, Ângela B. Kleiman, Brian Street, entre outros. Por meio desse estudo percebemos que a literatura oral tanto quanto a escrita apresenta grande potencial literária, que os sons, o ritmo, as cores, os gestos também compõem a poética da voz e que o Movimento de Mulheres Trabalhadoras Rurais (MMTR) de Inhambupe agencia letramentos, não apenas entre as integrantes do Movimento, mas também para o público leitor/ouvinte. [Recebido: 31 out. 2017 – Aceito: 4 dez. 2018]
- Published
- 2018
45. Development of antimicrobial leather modified with Ag–TiO2 nanoparticles for footwear industry
- Author
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Paulo J. Ferreira, Lorenzo Pastrana, C. Mansilla, Stanislav Ferdov, Miguel A. Cerqueira, Sandra Carvalho, S. M. Marques, Mariana Henriques, Carmen Gaidau, Isabel Carvalho, and Universidade do Minho
- Subjects
Anatase ,Materials science ,Renewable Energy, Sustainability and the Environment ,Cytotoxicity ,Tio2 nanoparticles ,Nanoparticle ,02 engineering and technology ,Antimicrobial activity ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Antimicrobial ,01 natural sciences ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,Ag–TiO nanoparticles 2 ,Leather ,Chemical engineering ,General Materials Science ,AgTiO nanoparticles ,Fourier transform infrared spectroscopy ,0210 nano-technology - Abstract
The proposed work aims to functionalize leathers for footwear industry with antimicrobial properties based on AgTiO2 nanoparticles. The synthesis of nanoparticles was carried out by the hydrothermal method with significant advantages in terms of time, energy savings and low cost. Anatase TiO2 nanoparticles with dimensions below 10nm were obtained as observed by X-ray diffraction and transmission electron microscopy. Fourier transform infrared spectroscopy showed that the based structure of leather was not modified by the addition of the nanoparticles. The antimicrobial activity was evaluated and it was observed that Ag containing leathers gained antimicrobial activity. In addition, the nanoparticles were found to be non-cytotoxic. This achievement, by itself, should be quite appealing to the footwear industry as it could consist in a solid value-preposition given the commonness of fungal infections promoted by humidity, poor breathability and temperature that promote the expansion of the microflora of the skin., This research is sponsored by FEDER funds through theprogram COMPETE – Programa Operacional Factores de Competitividade and by the Portuguese Foundation for Science andTechnology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013, and UID/EMS/00285/2013 and in the framework of ERA-SIINN/0004/2013 project., info:eu-repo/semantics/publishedVersion
- Published
- 2018
46. Author Correction: Probing the relationship between late endogenous ERP components with fluid intelligence in healthy older adults
- Author
-
Diego Pinal, Sandra Carvalho, Diana Pereira, Jorge Leite, Ana Carolina Teixeira-Santos, and Adriana Sampaio
- Subjects
Multidisciplinary ,Text mining ,business.industry ,Science ,Medicine ,Endogeny ,Psychology ,business ,Fluid intelligence ,Cognitive psychology - Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Published
- 2021
47. Educação na Amazônia rondoniense: os desafios da Educação no/do Campo
- Author
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Ely Sandra Carvalho de Oliveira and Wendell Fiori de Faria
- Published
- 2021
48. ALFABETIZAÇÃO EM CLASSES MULTISSERIADAS NO CAMPO: DIFICULDADES E IMPASSES NA PRÁTICA DOCENTE
- Author
-
Ely Sandra Carvalho de Oliveira and Wendell Fiori de Faria
- Published
- 2021
49. Antimicrobial TiN-Ag Coatings in Leather Insole for Diabetic Foot
- Author
-
Sandra M. Marques, Isabel Carvalho, Teófilo R. Leite, Mariana Henriques, Sandra Carvalho, and Universidade do Minho
- Subjects
Antimicrobial properties ,Diabetic foot ,Science & Technology ,Ag nanoparticles ,sputtering ,leather ,diabetic foot ,antimicrobial properties ,Sputtering ,General Materials Science - Abstract
This work reports on TiN-Ag antimicrobial coatings deposited by d.c. magnetron sputtering on leather used for insoles on the footwear industry, studies involving the antimicrobial properties of Ag-based functionalized leathers by sputtering techniques are shown. The X-ray diffraction (XRD) results suggested the presence of crystalline fcc-TiN phase for the sample without silver, and also a fcc-Ag phase in the samples containing silver. According to the Scanning Electron Microscopy (SEM) analysis, the coatings were homogeneous and dispersed Ag clusters were detected on the surface of samples with silver content above 8 at. %. The Inductively coupled plasma—optical emission spectrometry (ICP-OES) analysis showed that the ionization of silver over time depends on the morphology of the coatings. The samples did not present cytotoxicity and only samples with incorporated silver presented antibacterial and antifungal activity, highlighting the potential of the TiN-Ag insole coatings for diseases such as diabetic foot., This research was supported by by Portuguese Foundation for Science and Technology (FCT) in the framework of Strategic Funding (co-financed via UIDB/04650/2020, UIDB/04469/2020 and UIDB/00285/2020 unit). The authors also thank the financial support in the framework of HEALTHYDENT-POCI-01-0145-FEDER-030708, ATRITO-0-POCI-01-545 0145-FEDER-030446, Science DiabetICC Footwear-Development of Innovative therapeutic footwear for diabetic feet project-POCI 01-0247-FEDER-039784 and On-Surf-POCI-01-0247-FEDER-024521, co-financed via FEDER (PT2020)., info:eu-repo/semantics/publishedVersion
- Published
- 2022
50. Development of Organoid-on-a-chip Platform for Preclinical Drug Screening
- Author
-
Sandra Carvalho, Diana Pinho, and Ana Vila
- Subjects
Computer science ,Organoid ,Nanotechnology ,Chip - Published
- 2020
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