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Zinc oxide and polylactic-co-glycolic acid (ZnO-PLGA) nanocomposites are known to exhibit different biomedical applications and antibacterial activity, which could be beneficial for adding to wound dressings after different surgeries. However, possible cytotoxic effects along with various unexpected activities could reduce the use of these prominent systems. This is correlated to the property of ZnO, which exhibits different polymeric forms, in particular, wurtzite, zinc-blende, and rocksalt. In this study, we propose a computational approach based on the density functional theory to investigate the properties of ZnO-PLGA systems in detail. First, three different stable polymorphs of ZnO were considered. Subsequently, the abilities of each system to absorb the PLGA copolymer were thoroughly investigated, taking into account the modulation of electrical, optical, and mechanical properties. Significant differences between ZnO and PLGA systems have been found; in this study, we remark on the potential use of these models and the necessity to describe crucial surface aspects that might be challenging to observe with experimental approaches but which can modulate the performance of nanocomposites.

After defining a new log-logistic model and studying its properties, some new bivariate type versions using “Farlie-Gumbel-Morgenstern Copula”, “modified Farlie-Gumbel-Morgenstern Copula”, “Clayton Copula”, and “Renyi’s entropy Copula” are derived. Then, using the Bagdonavicius-Nikulin goodness-of-fit (BN-GOF) test for validation, we proposed a goodness-of-fit test for a new log-logistic model. The modified test is applied for the “right censored” real dataset of survival times. All elements of the modified test are explicitly derived and given. Three real data applications are presented for measuring the flexibility and the importance of the new model under the uncensored scheme. Two other real datasets are analyzed for censored validation.

Large Cardamom (Amomum subulatum Roxb.) is one of the most valuable cash crop of the Himalayan mountain region including Nepal, India, and Bhutan. Nepal is the world’s largest producer of the crop while the Taplejung district contributes a 30%−40% share in Nepal’s total production. Large cardamom is an herbaceous perennial crop usually grown under the shade of the Uttis tree in very specialized bioclimatic conditions. In recent years, a decline in cardamom production has been observed which is being attributed to climate-related indicators. To understand the current dynamics of this under-canopy herbaceous crop distribution and its future potential under climate change, a combination of modelling, remote sensing, and expert knowledge is applied for the assessment. The results suggest that currently, Uttis tree cover is 10,735 ha in the district, while 50% (5198 ha) of this cover has a large cardamom crop underneath. When existing cultivation is compared with modelled suitable areas, it is observed that the cultivatable area has not yet reached its full potential. In a future climate scenario, the current habitat will be negatively affected, where mid elevations will remain stable while lower and higher elevation will become infeasible for the crop. Future changes are closely related to temperature and precipitation which are steadily changing in Nepal over time.

Currently, because of stricter environmental standards and highly competitive markets, machining operations, as the main part of the manufacturing cycle, need to be rigorously optimized. In order to simultaneously maximize the production quality and minimize the environmental issues related to the grinding process, this research study evaluates the performance of minimum quantity lubrication (MQL) grinding using water-based nanofluids in the presence of horizontal ultrasonic vibrations (UV). In spite of the positive impacts of MQL using nanofluids and UV which are extensively reported in the literature, there is only a handful of studies on concurrent utilization of these two techniques. To this end, for this paper, five kinds of water-based nanofluids including multiwall carbon nanotube (MWCNT), graphite, Al2O3, graphene oxide (GO) nanoparticles, and hybrid Al2O3/graphite were employed as MQL coolants, and the workpiece was oscillated along the feed direction with 21.9 kHz frequency and 10 µm amplitude. Machining forces, specific energy, and surface quality were measured for determining the process efficiency. As specified by experimental results, the variation in the material removal nature made by ultrasonic vibrations resulted in a drastic reduction of the grinding normal force and surface roughness. In addition, the type of nanoparticles dispersed in water had a strong effect on the grinding tangential force. Hybrid Al2O3/graphite nanofluid through two different kinds of lubrication mechanisms—third body and slider layers—generated better lubrication than the other coolants, thereby having the lowest grinding forces and specific energy (40.13 J/mm3). It was also found that chemically exfoliating the graphene layers via oxidation and then purification prior to dispersion in water promoted their effectiveness. In conclusion, UV assisted MQL grinding increases operation efficiency by facilitating the material removal and reducing the use of coolants, frictional losses, and energy consumption in the grinding zone. Improvements up to 52%, 47%, and 61%, respectively, can be achieved in grinding normal force, specific energy, and surface roughness compared with conventional dry grinding.

For many decades, non-timber forest products (NTFPs) have been an important livelihood commodity in Nepal as a traditional source of food, fiber, and medicines. However, the importance of NTFPs have been recognized only recently. NTFPs form more than 5% of Nepal’s national gross domestic product and are facing threat due to anthropogenic drivers and changing climate. Understanding of the current distribution and future dynamics of NTFPs is essential for effective conservation planning and management. In the maiden attempt, we used the Maxent model to understand the current and predict the future distribution by 2050 of 10 major NTFPs in Chitwan Annapurna Landscape, Nepal. The prediction accuracy of the models calculated based on the area under curve was high (>90%) and the prediction by 2050 highlights potential increase in distribution range of seven NTFPs and potential decrease in that of three NTFPs in the study area. The results from our study could play an important role in planning and management of these NTFPs considering their high economic and ecological significance and sensitivity to predicted climate change.

Background: Bacterial infections constantly have a large impact on public health, because of increased rates of resistance and reduced frequency of development of novel antibiotics. The utility of conventional antibiotics for treating bacterial infections has become increasingly challenging. The aim of the study was to assess the antibacterial effect of β-Lapachone (β-Lap), a novel synthetic compound., Methods: The antibacterial activity of the β-Lap compound was examined against laboratory strains by agar well diffusion method and broth dilution assay. Growth kinetics in presence of β-Lap on Staphylococcus aureus , Staphylococcus epidermidis , and Pseudomonas aeruginosa (ATCC 27853) were assessed by microplate alamarBlue assay. Crystal violet blue assay was used for biofilm inhibition and biofilm eradication. P. aeruginosa catalase (KatA) complexed with β-Lap was modeled using molecular docking approach., Results: β-Lap exhibited potent antimicrobial activity against laboratory strains of bacteria with MIC of 0.2 mM for S. saprophyticus and Staphylococcus aureus , and 0.04 mM for Staphylococcus epidermidis and Pseudomonas aeruginosa ATCC 27853. The inhibition of catalase enzyme was found to be the cause for its antibacterial activity. Bioinformatics analysis suggests that β-Lap can inhibit KatA activity by interacting with catalase proximal active site and heme binding site. The activity of some commercial antibiotics was enhanced in association with β-Lap. In addition, β-Lap inhibited the biofilm formation and eradicated the already formed and ultra-mature biofilms of aforesaid bacterial strains., Conclusion: These observations indicated that β-Lap could be a promising antibacterial agent for the treatment and prevention of infectious diseases.

Around the world, polycystic ovary syndrome (PCOS) is a complex endocrine-metabolic condition that typically affects 6-20% of females. Our study's major goal was to examine how chlorogenic acid (CGA) affected mice with endocrine and metabolic problems brought on by letrozole-induced PCOS. Group I served as the control for 81 days; Group II was given Letrozole (LETZ) orally at a dose of 6 mg/kg bw for 21 days to induce PCOS; Group III was given LETZ (6 mg/kg) for 21 days, followed by treatment with CGA (50 mg/kg bw daily) for 60 days. The study indicated that LETZ-treated mice displayed symptoms of PCOS, such as dyslipidemia, hyperinsulinemia, elevated testosterone, increases in inflammatory markers and malonaldehyde, and a decline in antioxidants (Ar, lhr, fshr, and esr2) in the ovaries. These alterations were affected when the mice were given CGA and were associated with reduced levels of adiponectin. Adiponectin showed interactions with hub genes, namely MLX interacting protein like (MLXIPL), peroxisome proliferator-activated receptor gamma Coactivator 1- alpha (PPARGC1), peroxisome proliferator-activated receptor gamma (Pparg), and adiponectin receptor 1 (Adipor1). Lastly, the gene ontology of adiponectin revealed that adiponectin was highly involved in biological processes. The findings from our research suggest that adiponectin has direct impacts on metabolic and endocrine facets of PCOS.

Comprehensive safety and efficacy studies of COVID-19 vaccines might reduce the apprehension of the general population about the adverse reactions and duration of protection offered by them. The study aimed to conduct a systemic review on the four COVID-19 vaccines (AstraZeneca, Pfizer, Moderna, and Janssen) approved in Saudi Arabia. The study was conducted by reviewing the published articles from electronic databases such as PubMed, Embase, Cochrane Library and Web of Science using the search terms "COVID-19", "Vaccine", "Safety", "Efficacy" and "Human trials" and as per the standard guidelines for systemic review. The review analyzed eighteen articles and the data from them were evaluated to analyze the safety and efficacy of the vaccines in different groups of population such as males, females, those above 18 years and people with co-morbidities. The common local reactions observed after vaccination were pain at the site of injection (40-70%), redness (16-30%), swelling (18-39%) and tenderness (20-40%). The systemic reactions reported were fever (40-60%), chills (12-23%), fatigue (44-65%), headache (30-42%) and muscle pain (15-40%). The efficacy was observed to be above the threshold value (60%) stipulated by the WHO. However, precautions need to be followed while vaccinating special groups of population such as those that are pregnant, lactating or experiencing severe illness. Additionally, the rare and serious adverse events reported remotely after vaccination need more studies.

The study aimed at evaluating the antioxidant profile of a medicinal epiphyte Viscum album L. harvested from three tree species, namely, Populus ciliata L, Ulmus villosa L., and Juglans regia L. The crude extracts were obtained with ethanol, methanol, and water and were evaluated for the total phenol content (TPC), total flavonoid content (TFC), and antioxidant activities using total reducing power (TRP), ferric reducing antioxidant power (FRAP), 1, 1-diphenyl 1-2-picryl-hydrazyl (DPPH), superoxide radical scavenging (SOR), and hydroxyl radical scavenging ( • OH) assays. Our results showed that crude leaf extracts of plants harvested from the host Juglans regia L. exhibited higher yields of phytochemical constituents and noticeable antioxidative properties. The ethanolic leaf samples reported the highest phenols (13.46 ± 0.87 mg/g), flavonoids (2.38 ± 0.04 mg/g), FRAP (500.63 ± 12.58 μM Fe II/g DW), and DPPH (87.26% ± 0.30 mg/mL). Moreover, the highest values for TRP (4.24 ± 0.26 μg/mL), SOR (89.79% ± 0.73 mg/mL), and OH (67.16% ± 1.15 mg/mL) were obtained from aqueous leaf extracts. Further, Pearson correlation was used for quantifying the relationship between TPC, TFC, and antioxidant (FRAP, DPPH, SOR, OH) activities in Viscum album L. compared to their hosts. It was revealed that the epiphyte showed variation with the type of host plant and extracting solvent.