Elevated temperature impairs gonadal development by suppressing the expression of the genes for kisspeptin, GnRH1 and GTH subunits in Nile tilapia Oreochromis niloticus.

Temperature is a preeminent factor in the regulation of fish reproduction and hinders gonadal development beyond a specific threshold. To comprehend the molecular mechanism responsible for reproductive suppression at different temperature, expression of the genes encoding kisspeptin (kiss2), gonadotropin-releasing hormone (gnrh1) and their receptors (gpr54, gnrh1r) in the brain, and the gonadotropin (GTH) subunits (fshb and lhb) in the pituitary were studied in juvenile Nile tilapia (Oreochromis niloticus) along with gonadal histology. Fish were acclimatized to three distinct temperatures, including 31 °C, 34 °C and 37 °C for 14 days. The mRNA levels of kiss2, gpr54, gnrh1, and gnrh1r were significantly decreased at 37 °C compared to 31 °C and 34 °C in the both sexes. In parallel, the expression level of fshb in the both sexes and lhb in the female were significantly lower at 37 °C in the pituitary. Histologically, the gonads of both sexes had normal growth of gametes at control temperature (31 °C), whereas the spermatogenesis and oocyte maturation were slowed down and atretic oocytes were found in the ovary at 37 °C acclimation temperature. Taken together, the results imply that elevated temperature beyond the specific threshold may have a negative impact on reproduction by suppressing the gene expressions of kisspeptin/GnRH1/GTH system and eventually restrains normal growth and maturation of gametes in the both sexes of Nile tilapia.

Understanding the socio-demographic and programmatic factors associated with adolescent motherhood and its association with child undernutrition in Bangladesh.

BACKGROUND: Worldwide, a significant number of girls become mothers during adolescence. In Bangladesh, adolescent childbirth is highly prevalent and has adverse effects on children's health and undernutrition. We aimed to identify the relationship between the undernutrition of children and adolescent motherhood, the factors associated with adolescent mothers' age at first birth, and to examine the programmatic factors and gaps influencing children's undernutrition in Bangladesh. METHODS: We analysed the 'Bangladesh Demographic and Health Survey' BDHS-17-18 data and desk review. To examine the factors associated with adolescent motherhood and its impact on child undernutrition, data from 7,643 mother-child pairs were selected. Child stunting, wasting, and underweight were measured according to the World Health Organisation (WHO) median growth guidelines based on z-scores - 2. Univariate, bivariate, simple, and multiple logistic regressions were used for analyse. We followed the systematic procedures for the literature review. RESULTS: Approximately, 89% of adolescents aged ≤ 19 years were married and 71% of them gave their first childbirth. Children of adolescent mothers (≤ 19 years) were significantly 1.68 times more wasted (aOR: 1.68; 95% CI: 1.08 to 2.64), 1.37 times more underweight (aOR: 1.37; 95% CI: 1.01 to 1.86) and either form 1.32 times more stunting, wasting or underweight (aOR:1.32; 95% Cl: 1.05 to 1.66) compared to the children of adult mothers (> 19 years) after adjusting potential confounders. The factors associated with mothers' first childbirth during adolescence were the age gap between husband and wife 5-10 years (aOR: 1.81; 95% Cl: 1.57-2.10) and age gap > 10 years (aOR: 2.41; 95% Cl: 1.96-2.97) compared with the age group < 5 years, and husbands' education (aOR: 1.29; 95% Cl: 1.04-1.61) compared with the uneducated husbands. In the literature review, we found potential gaps in focusing on the Adolescent Sexual and Reproductive Health (ASRH) program in Bangladesh, from thirty-two programmes only half of them focused on adolescents aged 10-19 years, and eleven programmes focused only on girls. CONCLUSION: Children of adolescent mothers are at risk of wasting, underweight, and any form of undernutrition. For effective policies and interventions in Bangladesh, it is important to emphasise delaying adolescent pregnancy and prioritising child undernutrition.

Identification of abiotic stress responsive genes: A genome wide analysis of the cytokinin response regulator gene family in rice.

Response regulators (RRs), which are implicated in various developmental processes as well as environmental responses by acting as either positive or negative regulators, are crucial components of cytokinin signaling in plants. We characterized 36 RRs using in silico and computational analyses of publicly available data. A comprehensive analysis of OsRR family members was performed covering their physicochemical properties, chromosomal distribution, subcellular localization, phylogeny, gene structure, distribution of conserved motifs and domains, and gene duplication events. Gene Ontology analysis results indicate that 22 OsRR genes contribute mainly to the cytokinin-response and signal transduction. Predicted cis-elements in RRs promoter sequences related to phytohormones and abiotic stresses indicate that RRs are involved in hormonal and environmental responses as described in previous studies. MicroRNA (miRNA) target analysis showed that 148 miRNAs target 29 OsRR genes. In some cases, those RRs are targets of the same miRNA group, and may be controlled by common stimulus responses. Based on the analysis of publicly available gene expression data, OsRR4, OsRR6, OsRR9, OsRR10, OsRR22, OsPRR73, and OsPRR95 were found to be involved in response to abiotic stresses. Using quantitative reverse transcription polymerase chain reaction (qPCR) we confirmed that those RRs, namely OsRR4, OsRR6, OsRR9, OsRR10, OsRR22, and OsPRR73, are involved in the response to salinity, osmotic, alkaline and wounding stresses, and can potentially be used as models to understand molecular mechanisms underlying stress responsiveness.

Optimal growth conditions to enhance Chlorella vulgaris biomass production in indoor phyto tank and quality assessment of feed and culture stock.

Commercial microalgae cultivation is a dynamic field with ongoing efforts to improve efficiency, reduce costs, and explore new applications. We conducted a study to examine how different light exposure periods affect Chlorella vulgaris's growth. We employed a Phyto tank batch system of approximately 3.5 L with LED light control, controlled airflow, and sterilized bags, maintained at 22.0 ± 2.0 °C indoors. Various methods, including spectrophotometry, and cell counter were employed to monitor Chlorella vulgaris growth under different light exposure cycles. Additionally, quality analysis as feed source was employed by proximate, amino acid, beta-glucan, and microbial content analysis. The results revealed significant variations in C. vulgaris biomass production based on light exposure duration. Notably, the 16:8-h light-dark photoperiod exhibited the highest biomass concentration, reaching 6.48 × 107 ± 0.50 cells/mL with an optical density (OD) of 1.165 absorbance at 682 nm. The 12:12-h light-dark photoperiod produced the second-highest biomass concentration, with 2.305 × 106 ± 0.60 cells/mL at an OD of 0.489. Proximate analysis of dry algae powder revealed low lipid content (0.48 %), high protein content (37.61 %), variable ash concentration (average 10.75 %), and a significant carbohydrate fraction (51.16 %) during extended daylight and shorter dark periods. Amino acid analysis identified nine essential amino acids, with glutamic acid being the most abundant (17.7 %) and methionine the least (0.4 %). Furthermore, quality analysis and microbiological assays demonstrated that the C. vulgaris biomass is well-suited for fish and livestock use as a feed source and possibility as human nutraceuticals. These findings can be considered more environmentally friendly and ethically sound due to the absence of genetic modification.

Whole-genome sequencing of Klebsiella pneumoniae isolated from clinical specimens in Chattogram, Bangladesh.

The emergence of multidrug-resistant Klebsiella pneumoniae (Kpn) is a global concern due to the increasing rate of mortality and hospital cost burden in the affected population. This study reports the whole-genome sequences of nine multidrug-resistant Kpn from a hospital in Chattogram city of Bangladesh.

Investigating wave solutions and impact of nonlinearity: Comprehensive study of the KP-BBM model with bifurcation analysis.

In this paper, we investigate the (2+1)-dimensional Kadomtsev-Petviashvili-Benjamin-Bona Mahony equation using two effective methods: the unified scheme and the advanced auxiliary equation scheme, aiming to derive precise wave solutions. These solutions are expressed as combinations of trigonometric, rational, hyperbolic, and exponential functions. Visual representations, including three-dimensional (3D) and two-dimensional (2D) combined charts, are provided for some of these solutions. The influence of the nonlinear parameter p on the wave type is thoroughly examined through diverse figures, illustrating the profound impact of nonlinearity. Additionally, we briefly investigate the Hamiltonian function and the stability of the model using a planar dynamical system approach. This involves examining trajectories, isoclines, and nullclines to illustrate stable solution paths for the wave variables. Numerical results demonstrate that these methods are reliable, straightforward, and potent tools for analyzing various nonlinear evolution equations found in physics, applied mathematics, and engineering.

Bifurcation analysis and soliton solutions to the doubly dispersive equation in elastic inhomogeneous Murnaghan's rod.

The doubly dispersive (DD) equation finds extensive utility across scientific and engineering domains. It stands as a significant nonlinear physical model elucidating nonlinear wave propagation within the elastic inhomogeneous Murnaghan's rod (EIMR). With this in mind, we have focused on the integration of the DD model and the modified Khater (MK) method. Through the wave transformation, this model is effectively converted into an ordinary differential equation. In this paper, the goal of our work is to explore new wave solutions to the DD model by using the MK scheme. These solutions provide extremely helpful insights into the operation of the system. The three-dimensional (3D) plot and two-dimensional (2D) combined plot via the impacts of the parameters are provided for various parameters in this manuscript. We also discussed the dynamical properties of the model, which are accomplished through the bifurcation analysis, and also found the Hamiltonian function. This research makes a substantial contribution to the area by increasing our understanding of wave solutions in the DD, introducing novel investigation tools, and carrying out an in-depth investigation of the bifurcation and stability aspects of the system. As a direct result of this research, novel openings have been uncovered for further investigation and application in the various disciplines of science and engineering.

Insect meal in aquafeeds: A sustainable path to enhanced mucosal immunity in fish.

The mucosal surfaces of fish, including their intestines, gills, and skin, are constantly exposed to various environmental threats, such as water quality fluctuations, pollutants, and pathogens. However, various cells and microbiota closely associated with these surfaces work in tandem to create a functional protective barrier against these conditions. Recent research has shown that incorporating specific feed ingredients into fish diets can significantly boost their mucosal and general immune response. Among the various ingredients being investigated, insect meal has emerged as one of the most promising options, owing to its high protein content and immunomodulatory properties. By positively influencing the structure and function of mucosal surfaces, insect meal (IM) has the potential to enhance the overall immune status of fish. This review provides a comprehensive overview of the potential benefits of incorporating IM into aquafeed as a feed ingredient for augmenting the mucosal immune response of fish.

Evaluation of the modulating effect of epidermal growth factor receptor inhibitor cetuximab in carbon-tetrachloride induce hepatic fibrosis in rats.

Liver fibrosis, developed in almost all chronic liver injuries. Epidermal growth factor receptors (EGFR) have been thought to contribute to cirrhosis and liver fibrosis. Therefore, using a rat model of carbon tetrachloride (CCl4)-induced liver fibrogenesis, we investigated the preventive effects of cetuximab, an inhibitor of the EGF receptor (EGFR). Ameliorative effects of cetuximab were examined in rats, brought on by biweekly doses of 50 mg/kg of carbon tetrachloride (CCl4). There were a total of 24 male Long Evans rats split up into four distinct groups such as control, CCl4, control+cetuximab and CCl4+cetuximab. After two weeks of treatment with cetuximab (100 µg/kg), samples of tissue and blood were taken after all the rats had been sacrificed. Plasma samples were examined for the biochemical indicators of inflammation and oxidative stress. Histological staining on liver sections was performed for morphologic pathologies, and related genes expressions analysis were done with RT-PCR in liver tissue. The findings showed that cetuximab could raise the levels of glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) and considerably lower the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), malondialdehyde (MDA), and nitric oxide (NO). Sirius red staining and hematoxylin-eosin (H&E) displayed that cetuximab therapy reduced the inflammatory cells infiltration and enhanced fibrotic lesions. In the meantime, cetuximab therapy also dramatically reduces the expression of genes linked to inflammation in the liver tissue, including NF-кB, iNOS, IL-6, TNF-α, and TGF-ß. To sum up, the anti-inflammatory, antifibrotic, and antioxidant properties of cetuximab confer curative efficacy against liver fibrosis.

Comparative dataset on productivity, proximate, biochemical and pigment content of marine Gonyostomum sp. and freshwater Tetraedron sp. microalgae.

The dataset includes a comparative analysis of Gonyostomum sp. and Tetraedron sp. to characterize their productivity, proximate composition, biochemical composition and pigments. Growth data were collected through cell density and optical density and subsequently mass-cultured to utilize biomass for other analyses. The onset of the stationary phase (12 to 18 days) varied between the species. Volumetric productivity, areal productivity, and SGR were also significantly higher (p ˂ 0.05) in Gonyostomum sp. whereas, Tetraedron sp. showed significantly higher (p ˂ 0.05) cell duplication time and cell doublings per day (K). Gonyostomum sp. showed significantly higher (p ˂ 0.05) protein (42.86±1.13%), carbohydrate (13.56±0.48%) and lipid (27.4 ± 0.69%) content than Tetraedron sp. Significantly higher (p ˂ 0.05) polyunsaturated fatty acids (PUFA) were obtained from both Gonyostomum sp. and Tetraedron sp. Non-essential amino acids were prevalent in both microalgae than essential amino acids. Significantly higher (p ˂ 0.05) chlorophyll-a (5.51±0.00), chlorophyll-b (2.27±0.04) and phycobiliprotein (2.32±0.05) were found in Tetraedron sp. Conversely, Gonyostomum sp. exhibited higher (p ˂ 0.05) carotenoid content (2.48±0.05). These findings may contribute to the screening and utilization of these microalgae in the aquaculture, pharmaceuticals, and nutraceuticals sectors.

Genome sequence of white spot syndrome virus (WSSV) infecting cultured black tiger shrimp (Penaeus monodon) in Bangladesh.

The white spot syndrome virus (WSSV) is a causative agent of white spot disease (WSD) in crustaceans, especially in cultivated black tiger shrimp (Penaeus monodon), leading to significant economic losses in the aquaculture sector. The present study describes four whole genome sequences of WSSV obtained from coastal regions of Bangladesh.

Hypoxia alters the upper thermal limits and blood physiology in zebrafish, Danio rerio.

Hypoxic aquatic environments occur more frequently as a result of climate change, thereby exerting challenges on the physiological and metabolic functions of aquatic animals. In this study, a model fish, zebrafish (Danio rerio) was used to observe the climate-induced hypoxic effect on the upper thermal limit (critical thermal maximum; CTmax), hemoglobin, and blood glucose levels, and abnormalities of erythrocytes at cellular and nuclear level. The value of CTmax decreased significantly under hypoxia (39.10 ± 0.96 °C) compared to normoxia (43.70 ± 0.91 °C). At CTmax, hemoglobin levels were much lower (9.33 ± 0.60 g/dL) and blood glucose levels were significantly higher (194.20 ± 11.33 mg/L) under hypoxia than they were under normoxia and at the beginning of the experiment. Increased frequencies of abnormalities in the erythrocytes at both cellular (fusion, twin, elongated, spindle and tear drop shaped) and nuclear (micronucleus, karyopyknosis, binuclei, nuclear degeneration and notched nuclei) levels were also found under hypoxia compared to normoxia. These results suggest that hypoxic conditions significantly alter the temperature tolerance and subsequent physiology in zebrafish. Our findings will aid in the development of effective management techniques for aquatic environments with minimum oxygen availability.

Nanotechnology-enhanced fiber-reinforced polymer composites: Recent advancements on processing techniques and applications.

Incorporating nanoparticles can significantly improve the performance and functionality of fiber-reinforced polymer (FRP) composites. Different techniques exist for processing, testing, and implementing nanocomposites in various industries. Depending on these factors, these materials can be tailored to suit the specific applications of the automotive and aerospace industries, defence industries, biomedical and energy sectors etc. Nanotechnology offers several potential benefits for composites, including improved mechanical properties, surface modification, and sensing capabilities. This paper discusses the different types of nanoparticles, nanofibers, and nano-coating that can be used for reinforcement, surface modification, and property enhancement in FRP composites. It also examines the challenges associated with incorporating nanotechnology into composites and provides recommendations for potential opportunities in future work. This study is intended to offer a comprehensive understanding of the current research on using nanotechnology in FRP composites and its potential impact on the composites industry.

Genetic determinants of SARS-CoV-2 and the clinical outcome of COVID-19 in Southern Bangladesh.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has had a severe impact on population health. The genetic determinants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in southern Bangladesh are not well understood. METHODS: This study aimed to determine the genomic variation in SARS-CoV-2 genomes that have evolved over 2 years of the pandemic in southern Bangladesh and their association with disease outcomes and virulence of this virus. We investigated demographic variables, disease outcomes of COVID-19 patients and genomic features of SARS-CoV-2. RESULTS: We observed that the disease severity was significantly higher in adults (85.3%) than in children (14.7%), because the expression of angiotensin-converting enzyme-2 (ACE-2) diminishes with ageing that causes differences in innate and adaptive immunity. The clade GK (n = 66) was remarkable between June 2021 and January 2022. Because of the mutation burden, another clade, GRA started a newly separated clustering in December 2021. The burden was significantly higher in GRA (1.5-fold) highlighted in mild symptoms of COVID-19 patients than in other clades (GH, GK, and GR). Mutations were accumulated mainly in S (22.15 mutations per segment) and ORF1ab segments. Missense (67.5%) and synonymous (18.31%) mutations were highly noticed in adult patients with mild cases rather than severe cases, especially in ORF1ab segments. Moreover, we observed many unique mutations in S protein in mild cases compared to severe, and homology modeling revealed that those might cause more folding in the protein's alpha helix and beta sheets. CONCLUSION: Our study identifies some risk factors such as age comorbidities (diabetes, hypertension, and renal disease) that are associated with severe COVID-19, providing valuable insight regarding prioritizing vaccination for high-risk individuals and allocating health care and resources. The findings of this work outlined the knowledge and mutational basis of SARS-CoV-2 for the next treatment steps. Further studies are needed to confirm the effects of structural and functional proteins of SARS-CoV-2 in detail for monitoring the emergence of new variants in future.

Study on the association and phase separation behavior of surfactants and promethazine hydrochloride: impact of ammonium electrolytes.

In the current study, the association and phase separation of cationic tetradecyltrimethylammonium bromide (TTAB) and nonionic Triton X-100 (TX-100) surfactants with promethazine hydrochloride (PMH) were investigated in aqueous ammonium-based solutions. The micellization nature of the TTAB and PMH drug mixture was examined by evaluating critical micelle concentration (CMC) and counterion binding extent (ß) at different salt contents and temperatures (298.15-323.15 K). Micelle formation in the TTAB + PMH mixture was enhanced in the presence of ammonium salts, whereas the process was delayed with an increase in temperature in the respective salt solution. With an increase in salt content, the cloud point (CP) of the TX-100 + PMH mixture decreased, which revealed that the respective progression occurred through the salting out phenomenon. In micellization and clouding processes, the changes in free energies ΔG0m and ΔG0c were found to be negative and positive, respectively, demonstrating that the corresponding processes are spontaneous and non-spontaneous. Standard enthalpies (ΔH0m/ΔH0c) and standard entropies (ΔS0m/ΔS0c) for the association and clouding processes, respectively, were also calculated and discussed. The core forces amid TTAB/TX-100 and PMH in the manifestation of electrolytes are dipole-dipole and hydrophobic forces among the employed components according to the values for ΔH0m/ΔH0c and ΔS0m/ΔS0c, respectively.

Comparison of Sampson and extended Martin/Hopkins methods of low-density lipoprotein cholesterol calculations with direct measurement in pediatric patients with hypertriglyceridemia.

OBJECTIVE: The Friedewald equation is the commonly used method of low-density lipoprotein cholesterol (LDL-C) calculation, requiring reflex to direct LDL-C measurement when triglycerides (TG) ≥ 400 mg/dL. Recently formulated Sampson and extended Martin/Hopkins methods have been validated with TG up to 800 mg/dL and thus have the potential to replace direct LDL-C measurement. Given the growing prevalence of childhood dyslipidemia, the objective of this study was to compare Sampson and extended Martin/Hopkins methods of LDL-C calculation with the direct measurement in a pediatric cohort with 400 ≤ TG ≤ 799 mg/dL. METHODS: This study retrieved standard lipid panels and corresponding direct LDL-C measurements of 131 patients with 400 ≤ TG ≤ 799 mg/dL from a pediatric population. Following the application of Sampson and extended Martin/Hopkins calculations, calculated values were compared with direct LDL-C measurements using ordinary least squares linear regression analysis and bias plotting. RESULTS: Both Sampson and extended Martin/Hopkins LDL-C calculations exhibited a strong correlation with the direct measurements (Pearson r = 0.89) in patients with 400 ≤ TG ≤ 800 mg/dL. Average percentages of bias of 45% and 21% were found between the direct LDL-C measurements and Sampson or extended Martin/Hopkins calculations, respectively. CONCLUSION: Both Sampson and extended Martin/Hopkins calculations are applicable as clinical alternatives of direct LDL-C measurement in pediatric patients given 400 ≤ TG ≤ 799 mg/dL.

Assigning mutational signatures to individual samples and individual somatic mutations with SigProfilerAssignment.

MOTIVATION: Analysis of mutational signatures is a powerful approach for understanding the mutagenic processes that have shaped the evolution of a cancer genome. To evaluate the mutational signatures operative in a cancer genome, one first needs to quantify their activities by estimating the number of mutations imprinted by each signature. RESULTS: Here we present SigProfilerAssignment, a desktop and an online computational framework for assigning all types of mutational signatures to individual samples. SigProfilerAssignment is the first tool that allows both analysis of copy-number signatures and probabilistic assignment of signatures to individual somatic mutations. As its computational engine, the tool uses a custom implementation of the forward stagewise algorithm for sparse regression and nonnegative least squares for numerical optimization. Analysis of 2700 synthetic cancer genomes with and without noise demonstrates that SigProfilerAssignment outperforms four commonly used approaches for assigning mutational signatures. AVAILABILITY AND IMPLEMENTATION: SigProfilerAssignment is available under the BSD 2-clause license at https://github.com/AlexandrovLab/SigProfilerAssignment with a web implementation at https://cancer.sanger.ac.uk/signatures/assignment/.

Effects of integrated plant nutrition systems with fertilizer deep placement on rice yields and nitrogen use efficiency under different irrigation regimes.

Improved fertilizer management, with a combination of organic and inorganic inputs, has the potential to enhance rice yield while maintaining soil health. However, studies on the effects of broadcast prilled urea (PU) and urea deep placement (UDP) applied in combination with organic inputs (poultry litter [PL] and vermicompost [VC]), as integrated plant nutrition systems (IPNSs), on rice yields and nitrogen use efficiency (NUE) under alternate wetting and drying (AWD) irrigation are limited. We conducted field experiments during the dry and wet seasons of 2018, 2019, and 2020 to investigate the effects of fertilizer treatments, including control (no nitrogen), UDP, PU, and IPNSs (PU + VC, PU + PL, and UDP + PL) on rice yield and NUE under two irrigation regimes - AWD and continuous flooding (CF). The results revealed that fertilizer treatment and irrigation regime had significant (p < 0.05) interaction effects on rice yield and the agronomic efficiency of N (AEN) during the dry season. UDP significantly (p < 0.05) boosted rice yield, total dry matter (TDM), and NUE as compared to broadcast PU in both wet and dry seasons. Similarly, the IPNS treatment of UDP with PL significantly (p < 0.05) boosted rice yield, TDM, and NUE in comparison to broadcast PU. Under AWD irrigation, UDP alone produced higher rice yields than other treatments, while UDP, and UDP with PL produced similar yields under CF irrigation. During the dry season, AWD irrigation significantly (p < 0.05) increased rice yield, TDM, and AEN when compared to CF conditions, but during the wet season, AWD irrigation demonstrated a rice yield and NUE equivalent to CF. This research implies that using a UDP alone or in combination with PL as an IPNS could be a good way to boost crop productivity while also maintaining soil fertility.

Microbiome pattern and diversity of an anadromous fish, hilsa shad (Tenualosa ilisha).

BACKGROUND: The host-microbe interactions are complex, dynamic and context-dependent. In this regard, migratory fish species like hilsa shad (Tenualosa ilisha), which migrates from seawater to freshwater for spawning, provides a unique system for investigating the microbiome under an additional change in fish's habitat. This work was undertaken to detect taxonomic variation of microbiome and their function in the migration of hilsa. METHODS AND RESULTS: The study employed 16S rRNA amplicon-based metagenomic analysis to scrutinize bacterial diversity in hilsa gut, skin mucus and water. Thus, a total of 284 operational taxonomic units (OTUs), 9 phyla, 35 orders and 121 genera were identified in all samples. More than 60% of the identified bacteria were Proteobacteria with modest abundance (> 5%) of Firmicutes, Bacteroidetes and Actinobacteria. Leucobacter in gut and Serratia in skin mucus were the core bacterial genera, while Acinetobacter, Pseudomonas and Psychrobacter exhibited differential compositions in gut, skin mucus and water. CONCLUSIONS: Representative fresh-, brackish- and seawater samples of hilsa habitats were primarily composed of Vibrio, Serratia and Psychrobacter, and their diversity in seawater was significantly higher (P < 0.05) than freshwater. Overall, salinity and water microbiota had an influence on the microbial composition of hilsa shad, contributing to host metabolism and adaptation processes. This pioneer exploration of hilsa gut and skin mucus bacteria across habitats will advance our insights into microbiome assembly in migratory fish populations.

An implicit electrolyte model for plane wave density functional theory exhibiting nonlinear response and a nonlocal cavity definition.

We have developed and implemented an implicit electrolyte model in the Vienna Ab initio Simulation Package (VASP) that includes nonlinear dielectric and ionic responses as well as a nonlocal definition of the cavities defining the spatial regions where these responses can occur. The implementation into the existing VASPsol code is numerically efficient and exhibits robust convergence, requiring computational effort only slightly higher than the original linear polarizable continuum model. The nonlinear + nonlocal model is able to reproduce the characteristic "double hump" shape observed experimentally for the differential capacitance of an electrified metal interface while preventing "leakage" of the electrolyte into regions of space too small to contain a single water molecule or solvated ion. The model also gives a reasonable prediction of molecular solvation free energies as well as the self-ionization free energy of water and the absolute electron chemical potential of the standard hydrogen electrode. All of this, combined with the additional ability to run constant potential density functional theory calculations, should enable the routine computation of activation barriers for electrocatalytic processes.