Identifying SARS-CoV-2 Variants Using Single-Molecule Conductance Measurements.

The global COVID-19 pandemic has highlighted the need for rapid, reliable, and efficient detection of biological agents and the necessity of tracking changes in genetic material as new SARS-CoV-2 variants emerge. Here, we demonstrate that RNA-based, single-molecule conductance experiments can be used to identify specific variants of SARS-CoV-2. To this end, we (i) select target sequences of interest for specific variants, (ii) utilize single-molecule break junction measurements to obtain conductance histograms for each sequence and its potential mutations, and (iii) employ the XGBoost machine learning classifier to rapidly identify the presence of target molecules in solution with a limited number of conductance traces. This approach allows high-specificity and high-sensitivity detection of RNA target sequences less than 20 base pairs in length by utilizing a complementary DNA probe capable of binding to the specific target. We use this approach to directly detect SARS-CoV-2 variants of concerns B.1.1.7 (Alpha), B.1.351 (Beta), B.1.617.2 (Delta), and B.1.1.529 (Omicron) and further demonstrate that the specific sequence conductance is sensitive to nucleotide mismatches, thus broadening the identification capabilities of the system. Thus, our experimental methodology detects specific SARS-CoV-2 variants, as well as recognizes the emergence of new variants as they arise.

Insights into the interaction and inhibitory action of palmatine on lysozyme fibrillogenesis: Spectroscopic and computational studies.

Interaction under amyloidogenic condition between naturally occurring protoberberine alkaloid palmatine and hen egg white lysozyme was executed by adopting spectrofluorometric and theoretical molecular docking and dynamic simulation analysis. In spetrofluorometric method, different types of experiments were performed to explore the overall mode and mechanism of interaction. Intrinsic fluorescence quenching of lysozyme (Trp residues) by palmatine showed effective binding interaction and also yielded different binding parameters like binding constant, quenching constant and number of binding sites. Synchronous fluorescence quenching and 3D fluorescence map revealed that palmatine was able to change the microenvironment of the interacting site. Fluorescence life time measurements strongly suggested that this interaction was basically static in nature. Molecular docking result matched with fluorimetric experimental data. Efficient drug like interaction of palmatine with lysozyme at low pH and high salt concentration prompted us to analyze its antifibrillation potential. Different assays and microscopic techniques were employed for detailed analysis of lysozyme amyloidosis.Thioflavin T(ThT) assay, Congo Red (CR) assay, 8-anilino-1-naphthalenesulfonic acid (ANS) assay, Nile Red (NR) assay, anisotropy and intrinsic fluorescence measurements confirmed that palmatine successfully retarded and reduced lysozyme fibrillation. Dynamic light scattering (DLS) and atomic force microscopy (AFM) further reiterated the excellent antiamyloidogenic potency of palmatine.

Drawing the Linkage Between Women's Reproductive Health, Climate Change, Natural Disaster, and Climate-driven Migration: Focusing on Low- and Middle-income Countries - A Systematic Overview.

Background: One of the most important aspects of women's well-being and welfare is RSH (reproductive and sexual health). Reproductive health is not an exception to the threat that CCC (climate change and climate crisis) poses to numerous facets of public health. Firstly, the present review seeks to identify the influence of climatic changes, natural disasters, and climate-driven migration on RSH. Secondly, to identify knowledge gaps regarding the same. Material and Methods: Two databases (Scopus and PubMed) were scanned using Boolean operation. The literature search aimed to find records pertaining to topics of RSH and climate change. Using the PRISMA-ScR method, records were screened and shortlisted based on established inclusion criteria. This literature search was carried out in November 2022. In the shortlisted records, preference for the comprehensive review articles was given. Results: The present review is based on 38 records that collectively revealed that climate crisis and natural disasters have many negative impacts on female reproductive health. These effects are observed in different phases of life, ranging from teenage to menopause. The unique strength of the present review is that it draws a relationship between female reproductive health and the direct as well as indirect effects of the CCC. The available literature about LMICs is predominantly confined to drought, flood, and earthquake. Disasters like tsunamis, cyclones, and avalanches remain unexplored. Conclusion: From the available literature, it is quite evident that CCC has an adverse effect on a woman's reproductive life as well as a bearing on future generations' health. Filling these knowledge gaps is pivotal for designing more effective disaster and health policies. Policymakers should take into consideration these detrimental effects while designing health schemes and policies for females.

Automated radiosynthesis of mGluR5 PET tracer [18F]FPEB from aryl-chloro precursor and validation for clinical application.

The radioligand [18F]FPEB, used for PET imaging of the brain's metabotropic glutamate receptor subtype 5 (mGluR5), undergoes a thorough validation process to ensure its safety, efficacy, and quality for clinical use. The process starts by optimizing the synthesis of [18F]FPEB to achieve high radiochemical yield and purity. This study focuses on optimizing the radiolabeling process using an aryl-chloro precursor and validating the GMP production for clinical applications. Fully automated radiolabeling was achieved via one-step nucleophilic substitution reaction. [18F]FPEB was produced and isolated in high radioactivity and radiochemical purity. Throughout the validation process, thorough quality control measures are implemented. Radiopharmaceutical batch release criteria are established, including testing for physical appearance, filter integrity, pH, radiochemical purity, molar activity, radiochemical identity, chemical impurity, structural identity, stability, residual solvent, sterility, and endotoxin levels. In conclusion, the validation of [18F]FPEB involved a comprehensive process of synthesis optimization, quality control, which ensure the safety, efficacy, and quality of [18F]FPEB, enabling its reliable use in clinical PET. Here, we successfully radiolabeled and validated [18F]FPEB using aryl-chloro precursor according to GMP production for clinical application.

Interaction of food colorant indigo carmine with human and bovine serum albumins: A multispectroscopic, calorimetric, and theoretical investigation.

In this work we have studied the interaction of the food dye Indigo-Carmine (IndC) with the most studied model transport proteins i.e. human and bovine serum albumin (HSA & BSA). A multispectroscopic approach was used to analyze the details of the binding process. The intrinsic fluorescence of both the albumins was significantly quenched by IndC and the quenching was both static and dynamic in nature with the former being dominant. The HSA-lndC and BSA-IndC distance after complexation was determined by Förster resonance energy transfer (FRET) method which suggested efficient energy transfer from the albumins to IndC. Thermodynamics of serum protein-IndC complexation was estimated by isothermal titration calorimetry (ITC) which revealed that the binding was enthalpy driven. Circular dichroism (CD) and FTIR spectroscopy revealed that the binding of IndC induced secondary structural changes in both the serum proteins. Synchronous and 3D fluorescence spectroscopy revealed that the binding interaction caused microenvironmental changes of protein fluorophores. Molecular docking analysis suggested that hydrogen bonding and hydrophobic interactions are the major forces involved in the complexation process.

Effect of Hand and Ultrasonic Scaling-Root Planing Methods on Tooth Surface Topography: An In-Vitro Atomic Force Microscopy Study.

PURPOSE: Any instrumentation on the tooth surface for plaque or calculus removal will cause some amount of roughness on the tooth surface. Hence, this study was proposed to investigate the effects of hand and ultrasonic scaling and root planing on enamel and cementum, respectively. MATERIALS AND METHODS: Forty tooth samples were prepared from extracted maxillary and mandibular first pre-molars and were divided randomly into four groups of 10 samples each. Group l: received ultrasonic scaling on enamel; Group II: received hand scaling on enamel surface; Group III: root planing with an ultrasonic unit on the cementum samples; and Group IV: root planing using hand curettes on cementum surface. The amount of roughness produced on the surface of each sample of all four groups was evaluated using atomic force microscopy (AFM) and statistically analyzed using Chi-square, ANOVA, and Wilcoxon tests. RESULTS: The results suggested that the surface roughness produced on both crown and root after scaling and root planing (SRP) using a hand instrument is lower than that of an ultrasonic unit. The roughness of the crown was found to be lower than that of the root after SRP using both a hand instrument and an ultrasonic unit and was also statistically significant (P = 0.034). In contrast, there is not enough evidence to conclude a significant difference (P=0.13) between root planing using hand instruments and ultrasonic scaler groups. The combined p-value using the Chi-square test (P=0.026) suggests a statistically significant overall difference between crown and root groups. CONCLUSION: From the present study, the authors concluded that scaling as well as root planing using an ultrasonic unit cause more tooth (enamel and cementum) surface roughness as compared to hand scaling and root planing. While there is no significant difference in the surface roughness of root-cementum produced due to the root planing in both groups, crown-enamel exhibits a significant difference after scaling in both groups. Clinical significance of the study: Rough, uneven tooth surfaces negatively influence the anticipated healing of the periodontium by providing retention areas for microbial dental plaque.

Effect of ionic strength on aggregation of nile red and coumarin 30 in aqueous medium: primary kinetic salt effect or salting-out effect?

The effect of ionic strength on the aggregation of planar dyes like nile red (NR) and coumarin-30 (C30) in aqueous medium has been explored. The dyes are known to undergo dimerization, resulting in fading of their respective colors in the visible range. The present study demonstrates that the fading process is accelerated appreciably upon increasing ionic strength of the solution through addition of soluble salts. Experiments consist of variation of cations (Na+, Mg2+ and Al3+) with different valencies in a series of salts keeping the anion same and a similar set with a variation of anions (NO3-, SO42- and PO43-), keeping the cation same. The question of involvement of 'primary kinetic salt effect' or 'salting-out effect' for accelerating the aggregation process has also been resolved. Using Na+, K+ and NH4+ ions with the same counterpart NO3-, our experimental results do not show any differential effect, in terms of making the aggregation process faster, and hence rule out any effect of Hofmeister series on the self-aggregation process. The detailed study explicitly establishes that it is the 'primary kinetic salt effect' and not the 'salting-out effect' that is involved in the present case.

Synthesis of Cu (II) and Zn (II) Complexes of a Quinoline Based Flexible Amide Receptor as Fluorescent Probe for Dihydrogen Phosphate and Hydrogen Sulphate and Their Antibacterial Activity.

A novel 8-hydroxy quinoline-derived amide receptor, in conjunction with its Cu (II) and Zn (II) complexes, has been strategically developed to function as remarkably efficient fluorescent receptors with a distinct capability for anion sensing. The comprehensive characterization of the synthesized compounds were achieved through UV-Vis, IR, NMR, and HRMS spectroscopic techniques. Among the Cu (II) and Zn (II) complexes, the latter exhibits superior selectivity for anions, specifically dihydrogen phosphate and hydrogen sulfate, as their tetrabutylammonium salts in a 9:1 acetonitrile-water (v/v) mixture. The Cu (II) complex demonstrates enhanced anion binding compared to the amide ligand, albeit with reduced selectivity. Furthermore, the affinity was evaluated using the Benesi-Hildebrand plot. The binding constants and Limit of Detection (LOD) for both complexes were precisely quantified. The Job plot illustrates a clear 1:1 binding interaction between the metal complexes and the guest anions. Significantly, both metal-complex receptors display a broad spectrum of antibacterial activity, against both gram-positive and gram-negative bacteria. It is worth highlighting that the Zn (II) complexed receptor outperforms the Cu (II) complexed receptor, as evidenced by its considerably lower Minimum Inhibitory Concentration (MIC) value against both bacterial strains.

Design of a Liquid Impregnated Surface with a Stable Lubricant Layer in a Mixed Water/Oil Environment for Low Hydrate Adhesion.

Clathrate hydrate is a naturally occurring icelike solid that forms in the water phase under suitable temperature and pressure conditions in the presence of one or more hydrophobic molecules. It also forms inside the oil and gas pipes, leading to higher pumping cost, flow blockage, and even catastrophic accidents. Engineered surfaces with low hydrate adhesion can provide an effective solution to this problem. Liquid impregnated surfaces are examples of engineered surfaces that have already shown tremendous potential for reducing the nucleation and adhesion of solids. Here, we report the design and synthesis of liquid impregnated surfaces with extremely low hydrate adhesion under an oil and water mixed environment. The most challenging aspect of designing these surfaces was to stabilize a lubricant layer simultaneously under water and oil. A detailed methodology to make such lubricant-stable surfaces from a theoretical perspective was described and experimentally validated for lubricant stability. Experimental measurements on such surfaces showed extremely low hydrate accumulation and 1 order of magnitude or more reduction in hydrate adhesion force.

Performance analysis of DNA crossbar arrays for high-density memory storage applications.

Deoxyribonucleic acid (DNA) has emerged as a promising building block for next-generation ultra-high density storage devices. Although DNA has high durability and extremely high density in nature, its potential as the basis of storage devices is currently hindered by limitations such as expensive and complex fabrication processes and time-consuming read-write operations. In this article, we propose the use of a DNA crossbar array architecture for an electrically readable read-only memory (DNA-ROM). While information can be 'written' error-free to a DNA-ROM array using appropriate sequence encodings its read accuracy can be affected by several factors such as array size, interconnect resistance, and Fermi energy deviations from HOMO levels of DNA strands employed in the crossbar. We study the impact of array size and interconnect resistance on the bit error rate of a DNA-ROM array through extensive Monte Carlo simulations. We have also analyzed the performance of our proposed DNA crossbar array for an image storage application, as a function of array size and interconnect resistance. While we expect that future advances in bioengineering and materials science will address some of the fabrication challenges associated with DNA crossbar arrays, we believe that the comprehensive body of results we present in this paper establishes the technical viability of DNA crossbar arrays as low power, high-density storage devices. Finally, our analysis of array performance vis-à-vis interconnect resistance should provide valuable insights into aspects of the fabrication process such as proper choice of interconnects necessary for ensuring high read accuracies.

Relationship Between Vitamin D Deficiency and Non-alcoholic Fatty Liver Disease: A Cross-Sectional Study From a Tertiary Care Center in Northern India.

Background Vitamin D levels are strongly associated with myocardial infarction, coronary artery disease, heart dysfunction, and even mortality. Non-alcoholic fatty liver disease (NAFLD) is a prevalent hepatic illness whose incidence has grown dramatically over the past several decades. Methodology This observational, cross-sectional study was conducted over 1.5 years (January 2019 to June 2020) at the Department of General Medicine of a tertiary care hospital in northern India on 100 adult patients with NAFLD admitted to the emergency ward, intensive care unit, and medical ward. Results In our study, of the 100 patients, 45.0%, 16.0%, and 39.0% of patients exhibited vitamin D deficiency, insufficiency, and sufficiency, respectively. Vitamin D deficiency was the highest among those aged 41-50 (54.2%) and lowest among those aged 30-40 (29.0%). We observed that vitamin D deficiency was less prevalent in people with a normal body mass index (39.1%) than in those who were overweight (91.7%). There was a significant (p < 0.05) association between the severity of vitamin D deficiency and the presence of hepatomegaly, splenomegaly, and ascites. Overall, the incidence of fatty liver was 49% among patients. There was a significant (p = 0.0001) correlation between fatty liver and serum vitamin D levels. The association between the proportion of patients with fatty liver and the degree of vitamin D deficiency was found to be significant (p = 0.04). The relationship between the distribution of patients according to insulin resistance and the degree of vitamin D deficiency was also statistically significant (p < 0.001). Conclusions Vitamin D deficiency is associated with an increased risk of NAFLD, as well as with the severity of NAFLD.

Visiblelight-induced ternary electron donor-acceptor complex enabled synthesis of 2-(2-hydrazinyl) thiazole derivatives and the assessment of their antioxidant and antidiabetic therapeutic potential.

A mild and eco-friendly visible-light-induced synthesis of 2-(2-hydrazinyl) thiazole from readily accessible thiosemicarbazide, carbonyl, and phenacyl bromide in the absence of a metal catalyst and/or any extrinsic photosensitizer is reported. This approach only requires a source of visible light and a green solvent at room temperature to produce the medicinally privileged scaffolds of hydrazinyl-thiazole derivatives in good to outstanding yields. Experimental studies support the in situ formation of a visible-light-absorbing, photosensitized colored ternary EDA complex. The next step is to prepare a pair of radicals in an excited state, which makes it easier to prepare thiazole derivatives through a SET and PCET process. DFT calculations additionally supported the mechanistic analysis of the course of the reaction. The antioxidant and antidiabetic properties of some of the compounds in the synthesized library were tested in vitro. All the investigated compounds demonstrated appreciable antioxidant activity, as evidenced by the reducing power experiment and the IC50 values of the DPPH radical scavenging experiment. Furthermore, the IC50 values for 4c, 4d, and 4g also demonstrated a strong α-amylase inhibitory effect.

DNA/Protein Binding and Apoptotic-Induced Anticancer Property of a First Time Reported Quercetin-Iron(III) Complex Having a Secondary Anionic Residue: A Combined Experimental and Theoretical Approach.

A new quercetin-based iron(III) cationic complex [Fe(Qr)Cl(H2O)(MeO)] (complex 1) is created in the current study by condensation of quercetin with ferric chloride in the presence of Et3N. Comprehensive spectroscopic analysis and conductometric measurement are used to pinpoint complex 1. The generated complex's +3-oxidation state has been verified by electron paramagnetic resonance (EPR) research. Density functional theory analysis was used to structurally optimize the structure of complex 1. Before biomedical use, a variety of biophysical studies are implemented to evaluate the binding capacity of complex 1 with DNA and human serum albumin (HSA) protein. The findings of the electronic titration between complex 1 and DNA, as well as the stunning fall in the fluorescence intensities of the HSA and EtBr-DNA/DAPI-DNA domain after complex 1 is gradually added, give us confidence that complex 1 has a strong affinity for both macromolecules. It is interesting to note that the displacement experiment confirms partial intercalation as well as the groove binding mechanism of the title complex with DNA. The time-dependent fluorescence analysis indicates that after interaction with complex 1, HSA will exhibit static quenching. The thermodynamic parameter values in the HSA-complex 1 interaction provide evidence for the hydrophobicity-induced pathway leading to spontaneous protein-complex 1 interaction. The two macromolecules' configurations are verified to be preserved when they are associated with complex 1, and this is done via circular dichroism spectral titration. The molecular docking investigation, which is a theoretical experiment, provides complete support for the experimental findings. The potential of the investigated complex to be an anticancer drug has been examined by employing the MTT assay technique, which is carried out on HeLa cancer cell lines and HEK-293 normal cell lines. The MTT assay results validate the ability of complex 1 to display significant anticancer properties. Finally, by using the AO/PI staining approach, the apoptotic-induced cell-killing mechanism as well as the detection of cell morphological changes has been confirmed.

Endoscopic vs microscopic facial nerve decompression for traumatic facial nerve palsy: a randomized controlled trial.

PURPOSE: To explore a minimally invasive trans-canal endoscopic facial nerve decompression for traumatic facial nerve palsy and compare it with microscopic facial nerve decompression. METHODS: 35 and 38 patients underwent endoscopic and microscopic facial nerve decompression, respectively, for traumatic facial nerve palsy. Onset of symptoms, type of temporal bone fracture, day of surgical intervention following trauma, ossicular chain status and nature of insult to facial nerve were observed. Time period for recovery (House Brackmann grade ≤ 3), long term recovery rates, pre- and post-operative hearing status, surgical time and post-operative pain were compared between groups. RESULTS: Maximum patients in endoscopic and microscopic groups (77.1% and 76.3%, respectively) had acute onset of symptoms. 57.1% (20/35) had longitudinal, 17.1% (6/35) had transverse and 25.7% (9/35) had mixed fractures in endoscopic group. In the microscopic group, 57.9% (22/38) had longitudinal, 18.4% (7/38) had transverse and 23.7% (9/38) had mixed fractures. The mean (± S.D.) post-operative air-bone gap in endoscopic and microscopic group were 16.47 ± 4.5 dB and 19.4 ± 5.2 dB, respectively, which was statistically significant. The mean (± S.D.) time period for recovery of endoscopic and microscopic groups were 14.4 ± 5 days and 22.5 ± 7 days, respectively (p value < 0.05). The difference in post-operative pain between the two groups was also statistically significant. The difference in long term recovery rates was not statistically significant (p > 0.05). CONCLUSIONS: Endoscopic facial nerve decompression results in early recovery, less post-operative pain and better post-operative air-bone gap closure when compared to conventional microscopic technique.

Menstrual hygiene practices and their determinants among pre-menopausal married women in rural Puducherry.

Background: Menstrual hygiene practices are somewhat poor among pre-menstrual aged rural women, and thereby, they are likely to be affected by menstrual and gynaecological morbidities. Hence, an attempt is made to comprehend the magnitude of menstrual hygiene practices through an index among rural women and identify its principal determinants. Methods: Adopting a community-based cross-sectional study design, the required data was collected (through a semi-structured interview schedule) from 780 married pre-menopausal women (aged 35-49 years) from 30 villages of the Puducherry district during January-April 2021. Descriptive and inferential statistics and multiple linear regression techniques were employed. Results: 56% of the present study respondents have exhibited good menstrual hygienic practices (pooled scores 9-15; Median score = 9). Findings from the multiple linear regression model revealed that women's education (ß = 0.235; P < 0.001), occupational hierarchy (ß = 0.110; P < 0.001) and mass media exposure (ß = 0.095; P < 0.01) as the critical predictors of menstrual hygiene practices. Such positive net effects were also exhibited by the family monthly income (ß = 0.84; P < 0.05) and women's access to economic resources (ß = 0.071; P < 0.05), whereas family size demonstrated a significant adverse effect (ß = -0.080; P < 0.05). Conclusions: Overall, menstrual hygiene practices among women are moderately high among better socio-economic status. Efforts may be taken to improve the socio-economic conditions and propagate the correct menstrual hygienic practices among rural women, which may enhance hygiene practices during menstruation.

Maternal depression: Technology enabled self screening in real time.

The first step toward providing treatment, is getting the right diagnosis in real time; before it is too late. Without this, resource deployment may appear to be comparable to the scale and scope of the problem, while in reality it may just be a drop in the ocean. Maternal depression, during pregnancy is a debilitating risk to both the mother and the child, but the bigger problem is, it goes unnoticed, undetected, and therefore untreated. If mobile technology can be deployed to screen for depression in real time by the pregnant mother herself, it will go miles in creating a HOPE for health.

Exploration of Self-Aggregation of Coumarin 7 and Coumarin 30 in Water: Role of ß-Cyclodextrin as a Modulator.

Steady-state and time-resolved spectroscopic studies demonstrate that two members of the coumarin class of dyes, coumarin 7 (C7) and coumarin 30 (C30), undergo self-aggregation in water. The development of hypsochromically shifted new absorption bands in addition to the existing monomer bands with an increase in concentration of the dyes in an aqueous medium suggests that the aggregates are of H-type. An absorption-based kinetic study reveals that the rate of aggregation of C30 is an order of magnitude faster than that of C7. Second-order rate kinetics, as obtained from the half-life (t1/2) data, implies that the aggregates are dimeric in nature. Observations of isosbestic points in area-normalized absorption spectra (ANAS) and isoemissive points in area-normalized fluorescence excitation spectra (ANFES) and time-resolved area-normalized emission spectra (TRANES) establish that ground-state monomer ⇌ dimer equilibria for both of the systems are preserved in the photoexcited state. The present study further establishes that ß-cyclodextrin is the most efficient of the three common cyclodextrins in shifting the equilibria toward the monomer by encapsulating the monomers within its cavity, making ß-CD a convenient modulator to control the self-aggregation process. Dynamic light scattering (DLS), quantum chemical calculations, and molecular docking studies provide further support to our propositions.

A machine learning approach for accurate and real-time DNA sequence identification.

BACKGROUND: The all-electronic Single Molecule Break Junction (SMBJ) method is an emerging alternative to traditional polymerase chain reaction (PCR) techniques for genetic sequencing and identification. Existing work indicates that the current spectra recorded from SMBJ experimentations contain unique signatures to identify known sequences from a dataset. However, the spectra are typically extremely noisy due to the stochastic and complex interactions between the substrate, sample, environment, and the measuring system, necessitating hundreds or thousands of experimentations to obtain reliable and accurate results. RESULTS: This article presents a DNA sequence identification system based on the current spectra of ten short strand sequences, including a pair that differs by a single mismatch. By employing a gradient boosted tree classifier model trained on conductance histograms, we demonstrate that extremely high accuracy, ranging from approximately 96 % for molecules differing by a single mismatch to 99.5 % otherwise, is possible. Further, such accuracy metrics are achievable in near real-time with just twenty or thirty SMBJ measurements instead of hundreds or thousands. We also demonstrate that a tandem classifier architecture, where the first stage is a multiclass classifier and the second stage is a binary classifier, can be employed to boost the single mismatched pair's identification accuracy to 99.5 %. CONCLUSIONS: A monolithic classifier, or more generally, a multistage classifier with model specific parameters that depend on experimental current spectra can be used to successfully identify DNA strands.

An Investigation of a (Vinylbenzyl) Trimethylammonium and N-Vinylimidazole-Substituted Poly (Vinylidene Fluoride-Co-Hexafluoropropylene) Copolymer as an Anion-Exchange Membrane in a Lignin-Oxidising Electrolyser.

Electrolysis is seen as a promising route for the production of hydrogen from water, as part of a move to a wider "hydrogen economy". The electro-oxidation of renewable feedstocks offers an alternative anode couple to the (high-overpotential) electrochemical oxygen evolution reaction for developing low-voltage electrolysers. Meanwhile, the exploration of new membrane materials is also important in order to try and reduce the capital costs of electrolysers. In this work, we synthesise and characterise a previously unreported anion-exchange membrane consisting of a fluorinated polymer backbone grafted with imidazole and trimethylammonium units as the ion-conducting moieties. We then investigate the use of this membrane in a lignin-oxidising electrolyser. The new membrane performs comparably to a commercially-available anion-exchange membrane (Fumapem) for this purpose over short timescales (delivering current densities of 4.4 mA cm-2 for lignin oxidation at a cell potential of 1.2 V at 70 °C during linear sweep voltammetry), but membrane durability was found to be a significant issue over extended testing durations. This work therefore suggests that membranes of the sort described herein might be usefully employed for lignin electrolysis applications if their robustness can be improved.

Prevalence of anxiety and depression in South Asia during COVID-19: A systematic review and meta-analysis.

INTRODUCTION: The COVID-19 pandemic has impacted biopsychosocial health and wellbeing globally. Pre-pandemic studies suggest a high prevalence of common mental disorders, including anxiety and depression in South Asian countries, which may aggravate during this pandemic. This systematic meta-analytic review was conducted to estimate the pooled prevalence of anxiety and depression in South Asian countries during the COVID-19 pandemic. METHOD: We systematically searched for cross-sectional studies on eight major bibliographic databases and additional sources up to October 12, 2020, that reported the prevalence of anxiety or depression in any of the eight South Asian countries. A random-effects model was used to calculate the pooled proportion of anxiety and depression. RESULTS: A total of 35 studies representing 41,402 participants were included in this review. The pooled prevalence of anxiety in 31 studies with a pooled sample of 28,877 was 41.3% (95% confidence interval [CI]: 34.7-48.1, I 2 = 99.18%). Moreover, the pooled prevalence of depression was 34.1% (95% CI: 28.9-39.4, I 2 = 99%) among 37,437 participants in 28 studies. Among the South Asian countries, India had a higher number of studies, whereas Bangladesh and Pakistan had a higher pooled prevalence of anxiety and depression. No studies were identified from Afghanistan, Bhutan, and Maldives. Studies in this review had high heterogeneity, high publication bias confirmed by Egger's test, and varying prevalence rates across sub-groups. CONCLUSION: South Asian countries have high prevalence rates of anxiety and depression, suggesting a heavy psychosocial burden during this pandemic. Clinical and public mental health interventions should be prioritized alongside improving the social determinants of mental health in these countries. Lastly, a low number of studies with high heterogeneity requires further research exploring the psychosocial epidemiology during COVID-19, which may inform better mental health policymaking and practice in South Asia.