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Background: Amphibians are facing a global decline for the last few decades due to habitat loss, pesticide pollution, diseases and some other reasons. Fungal disease called chytridiomycosis has been emerged as one of the major causes of anuran extinction and decline in many parts of the globe. As the causal fungi Batrachochytrium dendrobatidis (Bd) were reported to have ubiquitous distribution on Earth, a survey was being conducted in districts of southern West Bengal, India, to assess probable anuran damage by the Bd in this region. A significant percentage of the common frogs Hoplobatrachus tigerinus and Phrynoderma hexadactylum were found to carry disease symptoms like redness of ventral skin, rashes, skin lesions, sluggish movements followed by death within 2 months. Results: Investigation pointed the causal factor as Alternaria alternata. Liver and lungs were the primarily affected organs. Histopathology identified the presence of spores in TS of infected lungs along with hepatocellular steatosis. Elevation of serum SGPT and triglyceride (~ tenfold and ~ threefold, respectively, compared to healthy groups) was also key findings in infected individuals. Infection prevalence was highest in South 24 Parganas (more than 7%). Conclusion: A common plant pathogen shifting host to anurans in a trans-kingdom way may be a significant evolutionary finding, but the infection being detrimental to two local frogs will have severe impacts. As the frogs are food web intermediates of their habitats, a collapse in local food web will be the primary ecological impact along with higher incidence of mosquito-borne diseases. [ABSTRACT FROM AUTHOR]

Bergsma (A new correlation coefficient, its orthogonal decomposition and associated tests of independence, arXiv preprint arXiv:math/0604627, 2006) proposed a covariance κ (X , Y) between random variables X and Y, and gave two estimates for it, based on n i.i.d. samples. He derived the asymptotic distributions of these estimates under the assumption of independence between X and Y. Our main focus is on the dependent case. This measure turns out to be same as the distance covariance (dCov) measure for multivariate X and Y, when we specialize to real-valued X and Y. We first derive several alternate expressions for κ , which are useful to understand the properties of κ and its estimates better. One of the alternate expressions for κ leads to a very intuitive third estimator of κ that is a nice function of four U-statistics. We establish the exact finite sample algebraic relation between the three estimates. This yields the relation between the bias of these estimators. In the dependent case, using the U statistics central limit theorem, it is easy to show that our estimate is asymptotic normal. The relation between the three estimates is then used to show that Bergsma's two estimates have the same limit distribution in the dependent case. When X and Y are independent, the above limit is degenerate. With a higher scaling, the non-degenerate limit distribution of all three estimators is obtained using the theory of degenerate U-statistics and the above algebraic relations. In particular, the known asymptotic distribution results for the two estimates of Bergsma for the independent case follow. For specific parametric bivariate distributions, the value of κ can be derived in terms of the natural dependence parameters of these distributions. In particular, we derive the formula for κ when (X, Y) are distributed as Gumbel's bivariate exponential. We bring out various aspects of these estimators through extensive simulations from several prominent bivariate distributions. In particular, we investigate the empirical relationship between κ and the dependence parameters, the distributional properties of the estimators, and the accuracy of these estimators. We also investigate the finite sample powers of these measures for testing independence, compare these among themselves, and with other well known such measures. Based on these exercises, the proposed estimator seems as good or better than its competitors both in terms of power and computing efficiency. [ABSTRACT FROM AUTHOR]

Purpose: Skeletal muscle ultrasound is a valuable tool for assessing muscle wasting in ICU. Previous studies on skeletal muscle ultrasound in ICU have been performed on lower limb muscles. The current study is formulated to assess the feasibility and reliability of anterior temporalis (AT) muscle ultrasound for measuring muscle wasting in ICU. Methods: In this prospective cohort study in 48 critically ill patients with sepsis, muscle layer thicknesses (MLTs) and mean grayscale (GS) values of anterior temporalis muscles and quadriceps femoris (Q) were measured at baseline and serially till 7 days. Correlation was made between baseline and change in MLT and GS values of AT and Q muscle and these parameters were compared between ICU survivors and non survivors. Results: Baseline anterior temporalis MLTs or their longitudinal changes over 7 days did not correlate significantly with the corresponding parameters of quadriceps femoris muscles. The baseline GS values of two muscle groups correlated weakly at baseline, but the change in GS over 7 days showed no correlation. The baseline MLTs of both muscle groups and their longitudinal change over 7 days did not correlate with ICU length of stay. The change in MLT of AT over 7 days was significantly greater in ICU non-survivors compared to survivors. Conclusion: Measurement of ultrasonographic muscle layer thickness and grayscale parameters of anterior temporalis muscle did not show good correlation with that of quadriceps muscle. [ABSTRACT FROM AUTHOR]

Suppose your father gives you a hollow cylindrical knife as a birthday gift, and your mother buys you a bag of potatoes. When the knife is pressed into a potato and the outer excess is removed, the interior of the knife yields a cylindrical core. By pressing the knife into a potato from several strategically chosen directions, you can construct some solids of intersection such that all faces are identical or one of two distinct shapes. [ABSTRACT FROM AUTHOR]

Background: The Himalayas have always been an enigma and, being biodiversity hotspots, are considered extremely important from an ecological point of view. Recent advances in studies regarding high-altitude lakes have garnered relevant importance as these habitats could harbor potential psychrophilic and psychrotrophic microbes with bio-prospective applications. Contemplating the above scenario, the present study has been undertaken to understand the diversity and the functional capacities of the microbes thriving in this lake. Results: In our present study on Samiti Lake, the abundance of Proteobacteria as the major phylum was seen in both the soil and water samples. Incase of the ABSLW (water) and ABS1 (soil) sample, 148,066 and 239,754 predicted genes, were taken for functional analysis. The KEGG analysis showed that ABSLW and ABS1 had 122,911 and 160,268, genes assigned to KO terms respectively. Whereas in case of COG functional analysis, 104,334 and 130,191 genes were assigned to different COG classes for ABSLW and ABS1 respectively. Further, on studying the glycoside hydrolases, an abundance of GH13, GH2, GH3, GH43, and GH23 in both the soil and water samples were seen. Conclusion: Our study has provided a comprehensive report about the bacterial diversity and functional capacities of microbes thriving in Samiti Lake. It has also thrown some light on the occurrence of glycoside hydrolases in this region, as they have numerous biotechnological applications in different sectors. [ABSTRACT FROM AUTHOR]

Background: The derivatives of quercetin is known for their immune-modulating antiviral, anti-blood clotting, antioxidant, and also for its anti-inflammatory efficacy. The current study was therefore conducted to examine the noted novel derivatives of quercetin present in plant sources as an immune modulator and as an antiviral molecule in the COVID-19 disease and also to study their affinity of binding with potential three targets reported for coronavirus, i.e., papain-like protease, spike protein receptor-binding domain, and 3C-like protease. Based on the high-positive drug-likeness score, the reported derivatives of quercetin obtained from an open-source database were further filtered. Compounds with positive and high drug-likeness scores were further predicted for their potential targets using DIGEP-Pred software, and STRING was used to evaluate the interaction between modulated proteins. The associated pathways were recorded based on the Kyoto Encyclopedia of Genes and Genomes pathway database. Docking was performed finally using PyRx having AutoDock Vina to identify the efficacy of binding between quercetin derivatives with papain-like protease, spike protein receptor-binding domain, and 3C-like protease. The ligand that scored minimum binding energy was chosen to visualize the interaction between protein and ligand. Normal mode analysis in internal coordinates was done with normal mode analysis to evaluate the physical movement and stability of the best protein-ligand complexes using the iMODS server. Results: Forty bioactive compounds with the highest positive drug-likeness scores were identified. These 40 bioactives were responsible for regulating different pathways associated with antiviral activity and modulation of immunity. Finally, three lead molecules were identified based on the molecular docking and dynamics simulation studies with the highest anti-COVID-19 and immunomodulatory potentials. Standard antiviral drug remdesivir on docking showed a binding affinity of − 5.8 kcal/mol with PLpro, − 6.4 kcal/mol with 3CLpro, and − 8.6 kcal/mol with spike protein receptor-binding domain of SARS-CoV-2, the discovered hit molecules quercetin 3-O-arabinoside 7-O-rhamnoside showed binding affinity of − 8.2 kcal/mol with PLpro, whereas quercetin 3-[rhamnosyl-(1- > 2)-alpha-L-arabinopyranoside] and quercetin-3-neohesperidoside-7-rhamnoside was predicted to have a binding affinity of − 8.5 kcal/mol and − 8.8 kcal/mol with spike protein receptor-binding domain and 3CLpro respectively Conclusion: Docking study revealed quercetin 3-O-arabinoside 7-O-rhamnoside to possess the highest binding affinity with papain-like protease, quercetin 3-[rhamnosyl-(1- > 2)-alpha-L-arabinopyranoside] with spike protein receptor-binding domain, and quercetin-3-neohesperidoside-7-rhamnoside with 3C-like protease and all the protein-ligand complexes were found to be stable after performing the normal mode analysis of the complexes in internal coordinates. [ABSTRACT FROM AUTHOR]

Background: Illicium griffithii is an aromatic medicinal tree species that has been listed in the IUCN Red List as an endangered species. Dried seed pods of I. griffithii have a good market potential in the spices and pharmaceutical industries. Fruits are the potential source of shikimic acid and used for the production of oseltamivir (a drug against bird flu). However, in recent years, unscientific harvesting and rampant exploitation of the species has caused a negative and adverse effect on its natural population. Proper knowledge of genetic diversity and population structure is crucial to understand the population dynamics, adaptation, and evolutionary pattern of a particular species for conservation. It was from this view point that the present study was undertaken so as to compare the various types of DNA-based molecular markers namely RAPD, ISSR, DAMD, and SCoT by their efficiency and SPAR approach to evaluate the genetic diversity of I. griffithii as well as to analyze population genetic structure for conservation purpose. Result: A total of 250 discernible bands were generated with 246 bands (98.40 %) being polymorphic in nature. All the primers in combination gave a mean polymorphic information content (PIC) of 0.81 and Rp value (resolving power) of 4.32. Nei's, Gst, and AMOVA analysis showed similar values of genetic differentiation among populations (Gst = 0.396, FST = 0.30, respectively), revealing a low level of genetic differentiation among the eight sampled populations. I. griffithii with an estimated gene flow value of Nm = 0.761 was significantly low among populations. Clustering pattern obtained with Bayesian structure and PCoA diagram revealed that intermixing of genetic material across populations is only possible when the populations lie close to each other. This is further validated with UPGMA clustering method where a positive correlation of genetic variability with geographical distance among closely related populations could be clearly seen. Conclusion: The result aids in the identification, collection, and preservation of diverse germplasm of I. griffithii from Arunachal Pradesh and Meghalaya of Northeast India. This would further help in understanding the population structure and genetic diversity among other Illicium species in order to formulate effective conservation strategies for the improvement of this endangered taxa. [ABSTRACT FROM AUTHOR]

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the etiologic agent of coronavirus disease 2019 (COVID-19), is rapidly acquiring new mutations. Analysis of these mutations is necessary for gaining knowledge regarding different aspects of therapeutic development. Previously, we have reported a Sanger method-based genome sequence of a viral isolate named SARS-CoV-2 NIB-1, circulating in Bangladesh. The genome has four novel non-synonymous mutations in V121D, V843F, A889V, and G1691C positions. Results: Using different computational tools, we have found V121D substitution has the potential to destabilize the non-structural protein-1 (NSP-1). NSP-1 inactivates the type-1 interferon-induced antiviral system. Hence, this mutant could be a basis of attenuated vaccines against SARS-CoV-2. V843F, A889V, and G1691C are all located in nonstructural protein-3 (NSP-3). G1691C can decrease the flexibility of the protein. V843F and A889V might change the binding pattern and efficacy of SARS-CoV-2 papain-like protease (PLPro) inhibitor GRL0617. V843F substitution in PLPro was the most prevalent mutation in the clinical samples. This mutation showed a reduced affinity for interferon-stimulated gene-15 protein (ISG-15) and might have an impact on innate immunity and viral spread. However, V843F+A889V double mutant exhibited the same binding affinity as wild type PLPro. A possible reason behind this phenomenon can be that V843F is a conserved residue of PLPro which damaged the protease structure, but A889V, a less conserved residue, presumably neutralized that damage. Conclusions: Mutants of NSP-1 could provide attenuated vaccines against coronavirus. Also, these mutations of PLPro might be targeted to develop better anti-SARS therapeutics. We hope our study will help to get better insides during the development of attenuated vaccine and PLPro inhibitors. [ABSTRACT FROM AUTHOR]

This paper deploys the information of 300 female domestic workers who work to make up the difference between subsistence requirements and the total earnings of the family. The determinants of monthly income of the workers are age, type of work, total family members, per-capita monthly household income, year of schooling and number of houses serviced. Low wages, low level of education, less control over assets and income, verbal and physical abuse and the absence of social security are reflected in their weak bargaining power which results in a low level of empowerment. Women's earnings do not always ensure empowerment, especially when the wages are low. Meaningful legal safeguards, welfare measures and other provisions for empowerment must be inducted in modern society to reduce injustices, deprivations and indignities towards female domestic workers. [ABSTRACT FROM AUTHOR]

• Selection of non-homologous and essential proteins as potential drug targets to minimize cross-reactivity. • Pathogen-specific proteins involved in unique metabolic pathways were prioritized. • dnaN-encoded Beta sliding clamp protein was identified as a promising drug target due to its high connectivity. • Molecular docking and MD simulation demonstrated stable complexes formation between the drug and the target protein. Xanthomonas oryzae pv. oryzae is a plant pathogen responsible for causing one of the most severe bacterial diseases in rice, known as bacterial leaf blight that poses a major threat to global rice production. Even though several experimental compounds and chemical agents have been tested against X. oryzae pv. oryzae , still no approved drug is available. In this study, a subtractive genomic approach was used to identify potential therapeutic targets and repurposible drug candidates that could control of bacterial leaf blight in rice plants. The entire proteome of the pathogen underwent an extensive filtering process which involved removal of the paralogous proteins, rice homologs, non-essential proteins. Out of the 4382 proteins present in Xoo proteome, five hub proteins such as dnaA, dnaN, recJ, ruvA, and recR were identified for the druggability analysis. This analysis led to the identification of dnaN-encoded Beta sliding clamp protein as a potential therapeutic target and one experimental drug named [(5R)-5-(2,3-dibromo-5-ethoxy-4hydroxybenzyl)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]acetic acid that can be repurposed against it. Molecular docking and 100 ns long molecular dynamics simulation suggested that the drug can form stable complexes with the target protein over time. Findings from our study indicated that the proposed drug showed potential effectiveness against bacterial leaf blight in rice caused by X. oryzae pv. oryzae. It is essential to keep in consideration that the procedure for developing novel drugs can be challenging and complicated. Even the most promising results from in silico studies should be validated through further in vitro and in vivo investigation before approval. [ABSTRACT FROM AUTHOR]

Advances in miniaturization of micromachines are receiving considerable industrial attention, with a crucial aspect of research being on precision positioning and manipulation at the micro-nanoscale. Nanopositioners are precision mechatronic systems designed to deal with objects at extremely precise resolution wherein piezoelectric actuators have a high potential to impact emerging markets. However, the major bottleneck in harvesting the advantages of piezoelectric actuator for nanopositioning is the presence of inherent nonlinearity, mostly hysteresis, along with the presence of external dynamical disturbance, and traditional feedback controller cannot handle. Dithering has been used in the parlance of piezoelectric actuation as a surprisingly simple yet powerful means of enhancing system performance. This research presents the design framework of an adaptive voltage dither control logic based on spectral analysis of the system output using normalized harmonic ratio. The proposed controller adaptively tunes the intensity of dither amplitude depending on the system response to an optimum value that yields satisfactory results. A commercially available piezo-actuator has been used to model the system along with hysteresis using Dahl model, and system parameters have been identified experimentally. Performance of the proposed controller has been investigated by subjecting the plant model to several real-time perturbations like plant parameter variation, sinusoidal motion tracking, multi-amplitude multi-frequency input signal, external disturbances like Gaussian and impulse, step response, etc., and with the results showing better control performance and disturbance rejection capability as compared to traditional feedback control. [ABSTRACT FROM AUTHOR]

The fundamental particle nature of the Dark Matter (DM) that constitutes more than 80% of the gravitating matter in the Universe is unknown. There is no suitable candidate for this DM in the Standard Model (SM) of particle physics. The so-called Weakly Interacting Massive Particles (WIMPs), predicted in many scenarios of possible new physics beyond the SM, are currently one of the most favoured candidates of the DM. A number of experiments worldwide are trying to directly detect these WIMPs in underground laboratories. Here we discuss the basic ideas behind the WIMP hypothesis and brie-y discuss the latest results of such experiments and future prospects. [ABSTRACT FROM AUTHOR]

Squalene produced under anaerobic conditions, by a strain of Torulaspora delbrueckii was extracted from the biomass using supercritical carbon dioxide. Minimum use of solvent, lower time of isolation and a higher selectivity of extraction merit use of supercritical fluid extraction (SFE) technique over solvent extraction of squalene, as optimized and reported previously. A maximum squalene yield of 11.12 μg g−1 (dry weight) of yeast cells was obtained at a temperature of 60 °C and pressure of 250–255 bar at a constant flow rate of 0.2l min−1 of carbon dioxide. Lyophilization prior to SFE increased the squalene yield to 430.52 μg g−1 dry weight of yeast cells, an amount that is far greater than that obtained by (2:1) chloroform–methanol solvent extraction. [ABSTRACT FROM AUTHOR]