Emerging materials for the electrochemical detection of COVID-19

The SARS-CoV-2 virus is still causing a dramatic loss of human lives worldwide, constituting an unprecedented challenge for the society, public health and economy, to overcome. The up-to-date diagnostic tests, PCR, antibody ELISA and Rapid Antigen, require special equipment, hours of analysis and special staff. For this reason, many research groups have focused recently on the design and development of electrochemical biosensors for the SARS-CoV-2 detection, indicating that they can play a significant role in controlling COVID disease. In this review we thoroughly discuss the transducer electrode nanomaterials investigated in order to improve the sensitivity, specificity and response time of the as-developed SARS-CoV-2 electrochemical biosensors. Particularly, we mainly focus on the results appeard on Au-based and carbon or graphene-based electrodes, which are the main material groups recently investigated worldwidely. Additionally, the adopted electrochemical detection techniques are also discussed, highlighting their pros and cos. The nanomaterial-based electrochemical biosensors could enable a fast, accurate and without special cost, virus detection. However, further research is required in terms of new nanomaterials and synthesis strategies in order the SARS-CoV-2 electrochemical biosensors to be commercialized. © 2021 Elsevier B.V

Transforming urinary stone disease management by artificial intelligence-based methods: A comprehensive review

Objective: To provide a comprehensive review on the existing research and evi-dence regarding artificial intelligence (AI) applications in the assessment and management of urinary stone disease.Methods: A comprehensive literature review was performed using PubMed, Scopus, and Google Scholar databases to identify publications about innovative concepts or supporting applica-tions of AI in the improvement of every medical procedure relating to stone disease. The terms "endourology", "artificial intelligence", "machine learning", and "urolithiasis"were used for searching eligible reports, while review articles, articles referring to automated procedures without AI application, and editorial comments were excluded from the final set of publica-tions. The search was conducted from January 2000 to September 2023 and included manu-scripts in the English language.Results: A total of 69 studies were identified. The main subjects were related to the detection of urinary stones, the prediction of the outcome of conservative or operative management, the optimization of operative procedures, and the elucidation of the relation of urinary stone chemistry with various factors.Conclusion: AI represents a useful tool that provides urologists with numerous amenities, which explains the fact that it has gained ground in the pursuit of stone disease management perfection. The effectiveness of diagnosis and therapy can be increased by using it as an alter-native or adjunct to the already existing data. However, little is known concerning the poten-tial of this vast field. Electronic patient records, containing big data, offer AI the opportunity to develop and analyze more precise and efficient diagnostic and treatment algorithms. Never-theless, the existing applications are not generalizable in real-life practice, and high-quality studies are needed to establish the integration of AI in the management of urinary stone dis-ease.CNN ; CNN

High temperature electrochemical oxidation of ethanol over perovskite-type oxides

Ethanol oxidation was investigated in a solid electrolyte electrochemical reactor using a perovskite-type oxide La0.6Sr0.2Co0.8Fe0.2O3 as anode. Experiments were conducted between 300-750 degreesC at atmospheric pressure in an ytrria-stabilized-zirconia continuous stirred tank reactor using fuel-rich reactant mixtures

Ethanol Utilization In Solid Oxide Fuel Cells: A Thermodynamic Approach

A thermodynamic analysis of electrical power generation in ethanol fueled solid oxide fuel cells (SOFCs) was made in the temperature range between 800-1200 K at atmospheric total pressure. A SOFC was considered being fed with the thermodynamic equilibrium products of ethanol a) steam reforming b) CO(2) reforming and c) partial oxidation. In each case, ethanol, steam, carbon oxides, methane and hydrogen were considered coexisting in the equilibrium mixture produced by different ethanol to oxidant (H(2)O, CO(2) and O(2)) initial ratios. The boundary conditions for carbonization were also examined. The theoretically derived values of the molar fractions of the species in equilibrium were used for the evaluation of the thermodynamic value of the electromotive force (emf) established in the cell under the equilibrium conditions. Finally, the maximum electrical power obtainable in SOFC was calculated in each case under consideration

A Multimethod Examination of the Relationship Between Coaching Behavior and Athletes' Inherent Self-Talk

The aim of the present research was to investigate the relationship between coaching behavior and athletes' inherent self-talk (ST). Three studies were conducted. The first study tested the construct validity of the Coaching Behavior Questionnaire (CBQ) in the Greek language, and provided support for its original factor structure. The second study examined the relationships between coaching behavior and athletes' ST in field, with two different samples. The results showed that supportive coaching behavior was positively related to positive ST (in one sample) and negatively related to negative ST (in both samples), whereas negative coaching behavior was negatively related to positive ST (in one sample) and positively related to negative ST (in both samples). Finally, the third study examined the relationships experimentally, to produce evidence regarding the direction of causality. The results showed that variations in coaching behavior affected participants' ST. Overall, the results of the present investigation provided considerable evidence regarding the links between coaching behavior and athletes' ST and suggested that coaches may have an impact on athletes' thoughts

Catalytic Behavior of La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3) Perovskite-Type Oxide Thin Films Deposited on YSZ During the Reaction of Ethanol Oxidation

The perovskite-type oxide La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3) was studied as an ethanol oxidation catalyst-anode as a probable candidate for future application in Solid Oxide Fuel Cells (SOFCs). The investigation was carried out at atmospheric total pressure in a fully Yttria-Stabilized Zirconia (YSZ) continuous stirred tank reactor (C.S.T.R.) at a temperature range between 300-700 degrees C. Preliminary results show that La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3) thin films deposited on the inner bottom of the one end closed YSZ tube present: a) mediocre ethanol oxidation catalytic activity at relatively low temperature values and b) thermal stability under the experimental conditions

Recent activity in the development of proton-conducting oxides for high-temperature applications

High-temperature proton-conducting materials constitute a unique class of oxide materials, which are able to exhibit protonic conductivity under hydrogen-containing atmospheres. Besides being of great fundamental interest, such oxide systems possess practical significance because they can achieve high protonic conductivity levels. This opens the possibility of using proton-conducting materials as electrolytes for a wide range of intermediate- and high-temperature solid oxide electrochemical devices. Recent advances in the field of solid oxide proton-conducting materials that belong to the class of perovskite-based materials (such as doped BaCeO3, BaZrO3, BaCeO3-BaZrO3, SrCeO3, and LaScO3) and to other classes of materials (such as doped Ba2In2O5, CeO2, and LaNbO4) are presented and analyzed in this review. In order to highlight the most appropriate materials for applications in electrochemical devices, the analysis is devoted to the establishment of correlations between compositional and structural characteristics and their transport, thermal and stability properties. © 2016 The Royal Society of Chemistry

Ethanol/water mixture permeation behavior through membrane electrode assembly (MEA) in PEMFC

Direct ethanol fuel cells (DEFCs) have been paid more and more attention in recent years due to the following advantages of ethanol: low toxicity, renewability and easy production by the fermentation of agricultural products [1]. Based on the present status of the electrolyte development, Naifon® membrane series is the most commonly used. It is well known that its conductivity is dependent on the water content in the membrane in a more a less linear fashion [2]. This necessitates sufficient water in the polymer electrolyte. On the other hand, water content can not be so high that the electrode will be flooded. Proper management of water through the membrane is indispensable for the desirable cell performance. Furthermore, ethanol can also permeate across Nafion® membranes, leading to a mixed potential and catalyst poison at the cathode, consequently causing the decreased cell performance and fuel utilization [3]. These both issues make it necessary to investigate the ethanol/water permeation behavior through membrane electrode assembly in PEMFCs. In the present work, water and ethanol crossover rates through membrane electrode assembly (MEA) were determined in a polymer electrolyte fuel cell (PEMFC). The investigated MEA consisted of two Pt/C electrodes (40 wt. %) and a Nafion®-115 membrane as the electrolyte. The anode compartment was pumped by ethanol aqueous solutions with different concentrations, and the cathode was supplied with high-purity helium at different flow rates to sweep off the permeated ethanol and water. The effluent from the cathode was on-line determined by gas Chromatograph (GC-14B, Shimadzu). The effect of the operation parameters such as the cell temperature, the carrier gas (He) flowrate at the cathode and the concentration of ethanol aqueous solutions on the ethanol/water permeation behavior was investigated. Based on the experimental results, it was found that the crossover rates of both water and ethanol increase with the increment of the operation temperature and the carrier gas (He) flow rate at the cathode. It was also found that the ethanol concentration had a significant effect on the crossover rates of ethanol and water. In the case of ethanol, the permeation rates presented a volcano behavior as the ethanol concentration increased, reaching a peak value when the ethanol concentration was 6.0 mol/L, which could be attributable to the different swelling behavior of Nafion® membrane in different ethanol aqueous solutions