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Silver nanoparticles (AgNPs) have garnered significant global attention from researchers due to their unique physicochemical properties and wide-ranging applications in industry and medicine. However, their release into aquatic ecosystems has raised concerns regarding potential ecotoxicological consequences. The present study investigated the effects of polyvinyl pyrrolidone-coated silver nanoparticles on Labeo rohita fingerlings, focusing on behavioural reactions, genotoxic effects, histological changes and bioaccumulation. L. rohita fingerlings were exposed to polyvinyl pyrrolidone-coated silver nanoparticles with sizes ranging from 18 to 29 nm for 7 days at concentrations of 100, 200, 400 and 800 ug/l. The nanoparticle zeta potential was found to be extremely negative, measuring − 55.5 mV for 18 nm and − 31.4 mV for 29 nm. Behavioural abnormalities, including respiratory distress, reduced responsiveness and erratic swimming, were observed in exposed groups compared to controls, with severity increasing with higher nanoparticle concentrations. Genotoxicity assessment revealed significantly higher DNA damage in kidney cells compared to gill cells. Histological examination of gill tissues showed clogging in primary and secondary lamellae, along with distorted anatomy, necrosis and vacuolar atrophy in peripheral tubules of the kidneys. The kidneys exhibited greater nanoparticle accumulation than the gills with prolonged exposure. Moreover, 18 nm AgNPs induced more pronounced DNA damage and histological alterations in the kidney and gill tissues compared to 29 nm nanoparticles. This study elucidates the critical role of monitoring AgNPs in aquatic systems, providing essential data on their behaviour and environmental impacts. The findings highlight the need for improved detection techniques and effective management of AgNP contamination. Future research should focus on developing more sensitive analytical methods, understanding long-term ecological effects and exploring innovative remediation strategies. [ABSTRACT FROM AUTHOR]

Long-term historical data and their interpretation are crucial aspects of understanding any kind of variation that exists as a result of changing environmental behaviour. The focus of the study is to characterize precipitation properties in the middle subdivision of the Mahanadi River basin (MRB). An eigen-based technique, also known as the maximum loading value approach, and gridded precipitation data with a resolution of 0.25° × 0.25° are presented to analyze the spatiotemporal properties of precipitation at different timeslot intervals. The meteorological data (gridded precipitation for 117 years from 1901 to 2017) has a special "k" field for spatial and temporal modes of spatial pattern analysis, which aids in the recognition of precipitation properties. The identified characteristics of the exclusive timeslot periods have been assessed for any dispersion as a function of annual precipitation. To cross-validate the identified patterns for distinctness and pairwise comparison, the Kolmogorov–Smirnov's D test was used. Southwest Mahanadi does not experience much variation in pattern size (± 3–5%), with a maximum variance of 39.09% during timeslot 2 (1940–1978). Similarly, the southeast Mahanadi observed a continuous increase in pattern size and was above 10% with a maximum variance of 28.53% during timeslot 3 (1979–2 017). While north-eastern Mahanadi experienced a continuous and significant decrease of > 14% of the total variance, with a maximum (42.48%) during timeslot 1 (1901–1939) and a minimum (28.14%) during timeslot 3 (1979–2017). There is no spatial pattern variability from summer to any of the timeslot intervals. [ABSTRACT FROM AUTHOR]

Insulin-like growth factors (IGF) are powerful mitogens for a wide range of cell types and play an essential role in growth and development. In the current study, molecular docking and structural analysis of Insulin-like growth factor receptors (IGF-1Ra), a tyrosine kinase receptor protein was performed. The outcomes revealed that IGF1Ra protein from C. carpio has nucleotide sequence of 5152 base pairs and open reading frame of 4224 base pairs with coding sequence (CDS) of 4224 that encodes 1407 amino acids (A.A). Protein structure validation and homology modeling of IGF-1Ra protein verify that the favored region contains 93.96% residues, while the allowed region contains 4.70% of amine acids. Through virtual screening of ligands and molecular docking, the maximum binding energy (− 8.8 kcal/mol) was observed in zinc sulphate heptahydrate ligand. Molecular interactions among different residues like ASN116, PRO35, LEU293 and PRO294 showed conventional hydrogen bonding. Subcellular localization and gene ontology revealed IGF-1Ra protein is utmost restricted in the nuclear region (42.1%) with score of 2.059 and ontology analysis indicated molecular function of 34.1%, biological process of 17.1% and cellular component of 23.2%. Phylogenetics and molecular evolutionary analysis showed IGF-1Ra protein is closely related to Labeo rohita and Danio rerio. Overall, the findings of present study may lead to the development of new molecules that may bind to the IGF-1Ra protein and will be helpful to stimulate fish growth. [ABSTRACT FROM AUTHOR]

The cloning and characterization of the complete coding sequence of the Clarias magur SRD5A1 (CmSRD5A1) gene, which encodes an enzyme responsible for regulating steroid levels by converting testosterone into 5α-dihydrotestosterone (DHT), have been successfully achieved. DHT plays a vital role in enabling the complete expression of testosterone's actions in neuroendocrine tissues. The ORF of the full-length cDNA sequence of SRD5A1 was 795 bp, translating into 265 amino acids, with a total length of 836 bp including UTRs. Like other vertebrates, the signal peptide analysis revealed that SRD5A1 is a non-secretory protein, and hydropathy profiles indicated that it is hydrophobic in nature. The 3D structure of CmSRD5A1 sequence generated above was predicted using highly accurate AlphaFold 2 in Google Colab online platform. CmSRD5A1 contains seven transmembrane helices connected by six loops, with the N-termini located on the periplasmic side and C-termini on the cytosolic side. Structural superimposition with known bacterial and human SRD5As showed very high structural similarity. The electrostatic potential calculation and surface analysis of CmSRD5A1 revealed the presence of a large cavity with two openings one highly electropositive towards the cytosolic side and another relatively neutral towards the transmembrane region. The structural comparison revealed that the electropositive side of the cavity should bind to NADPH and the steroid hormone in the hydrophobic environment. Polar residues binding to NADPH are highly conserved and the same as known strictures. The conserved residues involved in hydrogen bonding with the ketone group at C-3 in the steroids hence fevering Δ4 double-bond reduction are identified as E66 and Y101. Our findings showed that SRD5A1 expression was lower during the spawning phase than the preparatory phase in female fish, while the administration of Ovatide (a GnRH analogue) resulted in up-regulation of expression after 6 h of injection in the ovary. In males, the lowest expression was observed during the preparatory phase and peaked at 16 h post- Ovatide injection in the testis. The expression of SRD5A1 in the brain of female fish was slightly higher during the Ovatide stimulation phase than the spawning phase. This study represents the first report on the cloning and characterization of the full-length cDNA of SRD5A1 in Indian catfish. [ABSTRACT FROM AUTHOR]

Myxozoans are highly specialized metazoan parasites with a very diverse host range that live on aquatic hosts. In both wild and farm-raised fish, myxozoans are the most frequent parasites. The aim of the current study was to evaluate any myxozoan parasite found in different organs of Schizothorax richardsonii. Live fish were transported with artificial aeration to the University of Kashmir. Thirty-five fish specimens were examined during the study period, and only gills of 6 fish were determined to be infected. Taxonomic study was carried out with the help of different keys, and histopathologcal study was assayed in order to study the diseased organs of the fish. Besides, characterization of partial 18S rDNA gene was also done in the present study as per the standard procedures. The findings showed that the plasmodia were big, oval shaped, and white in color, measuring 1.5 × 2.0 mm. They were referred to as intralamellar vascular-type plasmodia (LV3). Histological changes in the gills included inflammation, gill epithelium lifting, hypertrophy of lamellar cells, and fusion of nearby gill lamellae. The myxospore body had a tiny ICP at the anterior end and was spherical to ovoidal in form, measuring 11.19 × 7.66 µm. Polar tubules were pyriform in shape and measuring 6.12 × 1.95 µm, having coils up to 7 in number. The gill plasmodium index showed a moderate level of infection (GPI 2). According to their phylogenetic relationships, M. richardsonii n. sp. was sister species to Myxobolus sp. KLT and Myxobolus dermiscalis–infecting scales of Labeo rohita from Myanmar and India, respectively. The novel sequence KU885918 and 30 additional sequences from closely related sequences showed 97% homogeneity or above in NCBI GenBank database. Moreover, the tree showed grouping based on the tissue tropism, host, and geographical location of the infected host. Morphological, histological, and molecular characterizations were used to identify a novel myxosporean parasite, Myxobolus richardsonii n. sp. in cold water fish, Schizothorax richardsonii (Heckel), obtained from Wullar Lake in Kashmir Himalayas, India. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effects of dietary valine (Val) on growth, hemato-biochemical parameters, immunity, enzymatic activities, antioxidant status and expression of target of rapamycin (TOR) and 4E-BP genes in rainbow trout, Oncorhynchus mykiss (1.57 ± 0.03 g; 5.10 ± 0.34 cm). Six isonitrogenous (450 g kg−1) and isoenergetic (20.90 kJ 100 g−1, gross energy) diets were designed to represent varied Val levels (10.5, 13.0, 15.5, 18.0, 20.5 and 23.0 g kg−1 dry diet basis). Growth parameters improved significantly (P < 0.05) with the amelioration of dietary Val level up to 18.0 g kg−1. Highest (P < 0.05) body protein content was noted at 18.0 g kg−1 dietary Val. Significant differences in hematological, intestinal enzymatic activities and antioxidant parameters were noted. However, plasma variables did not show any significant differences except aspartate transaminase and uric acid. Total protein content increased significantly, while the albumin and globulin content did not show any significant (P > 0.05) difference. Moreover expression of TOR mRNA and elF4E-binding protein (4E-BP) was observed higher (P < 0.05) at 18.0 g kg−1 Val. On the basis of results, optimum dietary Val requirement for maximal growth of rainbow trout was determined to be 18.19 g kg−1 of dry diet, corresponding to 40.42 g kg−1 of dietary protein. [ABSTRACT FROM AUTHOR]

The area is located in seismically active belt NW Himalaya resultant of collision between Indo-Eurasian plates. Due to presence of faults, folds, and active tectonics of Himalayan region, mountain front designs, behavior of fluvial system, and landform development have been extensively shaped and sculptured by tectonic activity. In the present study, the assessment of relative tectonic activity is carried out in the Sukhnag catchment using geomorphic indices: the stream length-gradient index (SL), basin asymmetry (Af), hypsometric integral (Hi), valley floor width-valley height ratio (Vf), basin shape (Bs), and mountain-front sinuosity (Smf). These indices were used to compute relative tectonic activity (Iat) among 14 sub-watersheds; class 1 (very high relative tectonic activity, nill); class 2 (high, SF 1, 2, 5, 6, 9, and 11); class 3 (moderate, SF 3, 4, 7, 8, and 13); and class 4 (low, SF10, 12, and 14). Tectonic activity is high in sub-watersheds where various tectonic imprints like stream deflections, straightness of streams, deep valleys, steep slopes, and lineaments of tectonic significance showed their presence; these lineaments showed linear trend with the dominant zones of earthquake epicenters in the surroundings. Thus, the areas with higher tectonic activity are analyzed by geomorphic indices, supported by presence of various geomorphic expressions, tectonic imprints and field evidences. [ABSTRACT FROM AUTHOR]

Global warming threatens the hydrological cycle, resulting in parched dry season and inferable from its serious impact on profitability of downpour sustained crops. Drought is considered to be one of the most complex natural hazards, affecting large community of people. The effect of drought can be minimized when the decision makers are equipped with suitable data regarding the spatiotemporal information of crop. A study has been conducted in Durg district of Upper Seonath sub-basin of Chhattisgarh state for assessing agricultural drought. Present study involved identification of drought characteristics using Standardized Precipitation Index (SPI). NDVI data (NOAA AVHRR) were utilized to assess drought based on inadequacy of soil moisture and rainfall. Rainfall records have been utilized in preparing maps for drought affected areas using integrated approach of SPI and Geographic Information System (GIS). The analysis of rainfall records indicated that extreme drought events had occurred in year 2000 and 2002. The most critical year being 2002 with more than 60% of area under dry condition. RAI is used to compare SPI results, which shows strong correlation (R2 > 0.95) between them. This study investigates potential use of VCI by examining its affects to paddy yield during drought year. So as to approve the VCI results, the relationship among yield productivity and VCI for chief unirrigated crops was plotted indicating good relationship (R2 > 0.62) among each other. The outcome of this study could be an essential step toward addressing the issue of drought vulnerability and can be used as a guide for the proper utilization of reservoirs in the study area. [ABSTRACT FROM AUTHOR]

One of the important objectives of water resources planning is to tap the maximum possible water available in the river basin that can be utilized particularly during the period of drought. This can be materialized by creating water storage structures. For this purpose initially, the first task could be the identification of suitable site for creating water storage sites. With the advent of Remote Sensing (RS) and Geographic Information System (GIS) techniques, it becomes easier for water resources planner to identify the suitable location of water storage structure within the basin. Present study demonstrates the identification of suitable location in the upper basin of Sheonath river in Chhattisgarh State, India. Based on the various physical characteristics of the basin, GIS based multi-criteria evaluation technique is being applied to determine the most suitable water storage sites. The suitable sites are assessed by considering the spatially varying parameters. These parameters include potential runoff, hydrologic soil group, land use, lineament, slope, stream order and settlement and basin area. Potential runoff is calculated from Soil Conservation Service Curve Number (SCS-CN) equation. Since, there is more than one parameter; it is significant to determine the importance of one layer over another layer. Analytic Hierarchy Process (AHP) is one of the multi-criteria decision making method resulting in the percentage relative importance. The AHP model consists of three levels objective i.e. suitable site for water storage, the parameter used and the alternatives. In the overlay process of GIS the relative importance determined by AHP is applied to produce suitable locations. Suitability is divided into three categories "suitability level 1", "suitability level 2" and "suitability level 3" representing storage tank, stop dam and check dam respectively. This mapping helps in selecting potential site for water storage structures in the basin. [ABSTRACT FROM AUTHOR]

A study was undertaken to investigate the prevalence rate, site preference and extent of damage caused by myxosporidian parasites in Punjab, India. During the 6 months study, 600 carp fingerlings belonging to 4 genera i.e. Labeo rohita Hamilton, Cirrhinus mrigala Hamilton, Catla catla Thail and Carassius carassius were randomly collected from the polyculture nursery ponds located in different villages District Fatehgarh Sahib, Punjab. Organs such as fins, scales, gills, intestine, kidney, and eye-ball were examined for the presence of myxozoan parasites. In this study, gills of 321 (53.50%) were found to be infected with as many as 10 species of myxosporean parasites belonging to the genus Myxobolus. Gills were examined for the presence of plasmodia and infected organs were processed for histology. The gill plasmodial index (GPI) was counted for all the 10 species and this revealed a mild to severe infection was recorded. M. knobii, M. majraiensis, M. markiwi, M. naini, M. rocatlae, M. vascularis and M. venkateshi formed intralamellar vascular type of plasmodia (LV1), M. nanokiensis formed (LV3) and M. potularis and M. slendrii formed intrafilamental type of plasmodium (FV2). Out of 231 infected fishes, mixed infection was recorded in 44 fishes (13.70%), which exhibited biparasitism and polyparasitism. No infection was recorded in exotic carp i.e. C. carassius. Physicochemical parameters of water were also recorded for the period of 6 months comprising 4 months of winter and 2 months of spring. The present study indicated that the prevalence of myxozoan parasite was 43% in November (24.0 °C) and increased to 54% with the decrease in temperature (22.65 °C). [ABSTRACT FROM AUTHOR]

This paper presents the morphological characteristics of two new species belonging to the genus Myxobolus viz M. knobii n. sp. and M. majraiensis n. sp., parasites infecting gill lamellae and gill filaments of fingerlings of Cirrhinus mrigala (Ham.) and Catla catla (Ham.) respectively collected from nursery ponds located in the village Fagan Majra, District Fatehgarh Sahib, Punjab (India). A total of 90 fingerlings were examined (40 Catla catla and 50 Cirrhinus mrigala). Out of which, 32 C. mrigala and 19 C. catla fishes were found infected. The total prevalence rate was recorded as 56.66%. The age of the fish was recorded as 2-3 months and length of the fish ranged 4-4.5 cm. The plasmodia of M. knobii n. sp. were round to irregular, 0.6-1.0 mm in diameter. Myxospores oval to spherical, pot-shaped in frontal view with a prominent knob at anterior end, measured 5.83 × 4.29 µm in size. Polar capsules were equal, broadly pyriform, 1.95 × 1.70 µm in size having 3-4 polar filament coils. The plasmodia of M. majraiensis n. sp. were round to oval, 0.8-1.5 µm in diameter. Myxospores egg-shaped in frontal view also having prominent knob at the anterior end, measured 8.58 × 5.2 µm in size. Polar capsules were equal, pyriform, 3.47 × 1.80 µm in size having 5-6 polar filament coils. Gill plasmodium index showed heavy infection in both of the species. This is the first report of myxobolid infection in the fingerlings of Indian major carps in nursery ponds in Punjab (India). [ABSTRACT FROM AUTHOR]