Electrocatalysis in Alkaline Media and Alkaline Membrane-Based Energy Technologies.

Hydrogen energy-based electrochemical energy conversion technologies offer the promise of enabling a transition of the global energy landscape from fossil fuels to renewable energy. Here, we present a comprehensive review of the fundamentals of electrocatalysis in alkaline media and applications in alkaline-based energy technologies, particularly alkaline fuel cells and water electrolyzers. Anion exchange (alkaline) membrane fuel cells (AEMFCs) enable the use of nonprecious electrocatalysts for the sluggish oxygen reduction reaction (ORR), relative to proton exchange membrane fuel cells (PEMFCs), which require Pt-based electrocatalysts. However, the hydrogen oxidation reaction (HOR) kinetics is significantly slower in alkaline media than in acidic media. Understanding these phenomena requires applying theoretical and experimental methods to unravel molecular-level thermodynamics and kinetics of hydrogen and oxygen electrocatalysis and, particularly, the proton-coupled electron transfer (PCET) process that takes place in a proton-deficient alkaline media. Extensive electrochemical and spectroscopic studies, on single-crystal Pt and metal oxides, have contributed to the development of activity descriptors, as well as the identification of the nature of active sites, and the rate-determining steps of the HOR and ORR. Among these, the structure and reactivity of interfacial water serve as key potential and pH-dependent kinetic factors that are helping elucidate the origins of the HOR and ORR activity differences in acids and bases. Additionally, deliberately modulating and controlling catalyst-support interactions have provided valuable insights for enhancing catalyst accessibility and durability during operation. The design and synthesis of highly conductive and durable alkaline membranes/ionomers have enabled AEMFCs to reach initial performance metrics equal to or higher than those of PEMFCs. We emphasize the importance of using membrane electrode assemblies (MEAs) to integrate the often separately pursued/optimized electrocatalyst/support and membranes/ionomer components. Operando/in situ methods, at multiscales, and ab initio simulations provide a mechanistic understanding of electron, ion, and mass transport at catalyst/ionomer/membrane interfaces and the necessary guidance to achieve fuel cell operation in air over thousands of hours. We hope that this Review will serve as a roadmap for advancing the scientific understanding of the fundamental factors governing electrochemical energy conversion in alkaline media with the ultimate goal of achieving ultralow Pt or precious-metal-free high-performance and durable alkaline fuel cells and related technologies.

The exploration of phytocompounds theoretically combats SARS-CoV-2 pandemic against virus entry, viral replication and immune evasion.

BACKGROUND: The novel coronavirus disease-2019 (COVID-19) that emerged in China, is an extremely contagious and pathogenic viral infection caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) that has sparked a global pandemic. The few and limited availability of approved therapeutic agents or vaccines is of great concern. Urgently, Remdesivir, Nirmatrelvir, Molnupiravir, and some phytochemicals including polyphenol, flavonoid, alkaloid, and triterpenoid are applied to develop as repurposing drugs against the SARS-CoV-2 invasion. METHODS: This study was conducted to perform molecular docking and absorption, distribution, metabolism, excretion and toxicity (ADMET) analysis of the potential phytocompounds and repurposing drugs against three targets of SARS-CoV-2 proteins (RNA dependent RNA polymerase, RdRp, Endoribonclease, S-protein of ACE2-RBD). RESULTS: The docking data illustrated Arachidonic acid, Rutin, Quercetin, and Curcumin were highly bound with coronavirus polyprotein replicase and Ebolavirus envelope protein. Furthermore, anti- Ebolavirus molecule Remedesivir, anti-HIV molecule Chloroquine, and Darunavir were repurposed with coronavirus polyprotein replicase as well as Ebolavirus envelope protein. The strongest binding interaction of each targets are Rutin with RdRp, Endoribonclease with Amentoflavone, and ACE2-RBD with Epigallocatechin gallate. CONCLUSIONS: Taken altogether, these results shed a light on that phytocompounds have a therapeutic potential for the treatment of anti-SARS-CoV-2 may base on multi-target effects or cocktail formulation for blocking viral infection through invasion/activation, transcription/reproduction, and posttranslational cleavage to battle COVID-19 pandemic.

Agonistic encounters and brain activation in dominant and subordinate male greater long-tailed hamsters.

During an agonistic encounter test, dominant male greater long-tailed hamsters (Tscheskia triton) initiated attacks sooner and displayed higher levels of aggression and flank marking behavior than their subordinate counterparts. Accordingly, subordinate males exhibited more defensive behavior than dominant ones. Specific patterns of neuronal activation, measured by Fos-immunoreactive staining (Fos-ir), were found in the hamster brain following agonistic interactions. Increased Fos-ir was observed in the bed nucleus of the stria terminalis (BST), ventromedial hypothalamus (VMH), and medial (MeA) and anterior cortical (ACo) nuclei of the amygdala (AMYG) in both dominant and subordinate males. In contrast, dominant males had significantly higher Fos-ir densities in the medial preoptic area (MPOA) than subordinate males, whereas subordinate males expressed higher densities of Fos-ir in the anterior hypothalamus (AH) and central nucleus of the amygdala (CeA). Additionally, Fos-ir levels in the MPOA were significantly correlated with aggression and Fos-ir levels in the AH and CeA were correlated with defensive behavior. Together, our data indicate distinct patterns of neuronal activation associated with agonistic encounters in a behavior-specific manner in male greater long-tailed hamsters.

Primary Generalized Glucocorticoid Hypersensitivity Treated with Mifepristone: A Case Report.

Here, we report a case of a patient with symptoms of Cushing syndrome, who is diagnosed with primary generalized glucocorticoid hypersensitivity in the end. The patient's relevant laboratory tests and imaging examinations are described. Mifepristone, a glucocorticoid receptor antagonist, was prescribed and its therapeutic effect on the patient's electrolyte level, lipid metabolism, and bone metabolism was observed during the treatment. The endocrine assessment indicated normal pituitary-adrenal axis regulation function but reduced cortisol secretion. Quantitative reverse transcription-polymerase chain reaction indicated reduced mRNA level of mineralocorticoid receptor gene. Pituitary magnetic resonance imaging showed normal pituitary anatomy, while adrenal computed tomography scan showed bilateral adrenal atrophy and increased content of visceral and abdominal subcutaneous fat. Moreover, chromosome examination revealed a normal 46, XY chromosome. In this case, mifepristone was administered to treat primary generalized glucocorticoid hypersensitivity. To the best of our knowledge, there are a few reports on mifepristone-treated primary generalized glucocorticoid hypersensitivity. In the one-year follow-up visits, the evaluated results of electrolyte level, lipid metabolism, and bone metabolism indicated that the patient's symptoms resulting from cortisol hypersensitivity were relieved progressively.

The combination of brain-computer interfaces and artificial intelligence: applications and challenges.

Brain-computer interfaces (BCIs) have shown great prospects as real-time bidirectional links between living brains and actuators. Artificial intelligence (AI), which can advance the analysis and decoding of neural activity, has turbocharged the field of BCIs. Over the past decade, a wide range of BCI applications with AI assistance have emerged. These "smart" BCIs including motor and sensory BCIs have shown notable clinical success, improved the quality of paralyzed patients' lives, expanded the athletic ability of common people and accelerated the evolution of robots and neurophysiological discoveries. However, despite technological improvements, challenges remain with regard to the long training periods, real-time feedback, and monitoring of BCIs. In this article, the authors review the current state of AI as applied to BCIs and describe advances in BCI applications, their challenges and where they could be headed in the future.

Photoexcited State Properties of Carbon Dots from Thermally Induced Functionalization of Carbon Nanoparticles.

Carbon dots are small carbon nanoparticles with various surface passivation schemes, in which more effective has been the deliberate chemical functionalization of the nanoparticles for brighter fluorescence emissions, though the synthesis method is more tedious and subject to some limitations in the selection of functionalization molecules. Another more popular synthesis method has been the carbonization of organic species, with the method being more efficient and versatile, but less controllable in the synthesis and for the desired dot structure and performance. In this work, a hybrid approach combining the advantageous characteristics of the two synthesis methods was applied to the preparation of carbon dots with polyethyleneimine (PEI) for surface passivation, where pre-processed and selected small carbon nanoparticles were functionalized with PEI in microwave-induced thermal reactions. The optical absorption and fluorescence emission properties were evaluated, and the results suggested that the carbon dots thus prepared shared the same photoexcited state characteristics with those from the deliberate chemical functionalization, including comparable fluorescence colors and other properties. A further demonstration on the similarity in photoexcited state properties was based on the same visible light-activated bactericidal functions of the PEI-carbon dots as those found in carbon dots from the deliberate chemical functionalization. The advantages and potential limitations of the hybrid approach for more controllable yet versatile and efficient syntheses of carbon dots are highlighted and discussed.

Species differences in the immunoreactive expression of oxytocin, vasopressin, tyrosine hydroxylase and estrogen receptor alpha in the brain of Mongolian gerbils (Meriones unguiculatus) and Chinese striped hamsters (Cricetulus barabensis).

Species differences in neurochemical expression and activity in the brain may play an important role in species-specific patterns of social behavior. In the present study, we used immunoreactive (ir) labeling to compare the regional density of cells containing oxytocin (OT), vasopressin (AVP), tyrosine hydroxylase (TH), or estrogen receptor alpha (ERα) staining in the brains of social Mongolian gerbils (Meriones unguiculatus) and solitary Chinese striped hamsters (Cricetulus barabensis). Multiple region- and neurochemical-specific species differences were found. In the anterior hypothalamus (AH), Mongolian gerbils had higher densities of AVP-ir and ERα-ir cells than Chinese striped hamsters. In the lateral hypothalamus (LH), Mongolian gerbils also had higher densities of AVP-ir and TH-ir cells, but a lower density of OT-ir cells, than Chinese striped hamsters. Furthermore, in the anterior nucleus of the medial preoptic area (MPOAa), Mongolian gerbils had higher densities of OT-ir and AVP-ir cells than Chinese striped hamsters, and an opposite pattern was found in the posterior nucleus of the MPOA (MPOAp). Some sex differences were also observed. Females of both species had higher densities of TH-ir cells in the MPOAa and of OT-ir cells in the intermediate nucleus of the MPOA (MPOAi) than males. Given the role of these neurochemicals in social behaviors, our data provide additional evidence to support the notion that species-specific patterns of neurochemical expression in the brain may be involved in species differences in social behaviors associated with different life strategies.

SigN is responsible for differentiation and stress responses based on comparative proteomic analyses of Streptomyces coelicolor wild-type and sigN deletion strains.

To address the functions of SigN (SCO4034) in Streptomyces coelicolor, we constructed a sigN null mutant M145Z, which showed a defect in sporulation. The differential proteomic profiles of wild-type S. coelicolors M145 and M145Z were demonstrated by two-dimensional polyacrylamide gel electrophoresis (2D PAGE), which identified 24 different spots that were up- or down-regulated due to sigN disruption. Among them, 22 proteins were identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The up-regulated proteins were involved in energy metabolism, stress responses, ATP binding, ppGpp stringent stress response and transcriptional anti-termination, etc. The down-regulated proteins were related to antibiotic synthesis and differentiation. The results gave a new insight into the regulatory mechanism of SigN in S. coelicolor. Furthermore, deletion of sigN caused growth retardation under all stress conditions examined including heat, cold, acid, oxidation, salt and ethanol. These results indicated that SigN was involved in morphological development, secondary metabolism and stress responses in S. coelicolor.