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Pattern of spatial variability in granulometric and mineralogical characteristics across an ecologically sensitive sub-tropical wetland(Bihar, India)

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International Journal of Sediment Research 2023年第4期38卷 516-529页

作者： Alvia Aslam rajesh kumar Ranjan Avinash Dass Department of Environmental Science Central University of South Bihar

Floodplain wetlands are dynamic systems undergoing frequent hydro-sedimentological changes. Tropical/subtropical wetlands have even more pronounced climatic and biological influences on the sediment dynamics. In the current study, a protected subtropical wetland in Bihar(India) has been assessed for its sedimentary and mineralogical status. Sediment characteristics and associated granulometric parameters are discussed to highlight the wetland’s hydrogeomorphic character, energy dimension, and the depositional processes taking place. Statistical grain size parameters like graphic mean, graphic skewness,graphic kurtosis, and their interrelations studies have helped in understanding the sources of deposited materials. Multivariate statistics have identified, sand fractions, measures of central tendencies(mean,median, and mode), percent organic matter(%OM) and percent carbonates(%carbonates) as primary factors explaining the maximum variance in the data. The non-parametric Kruskal-Wallis test has identified %sand, %clay, electrical conductivity(EC), and %carbonates as the major factors responsible for significant spatial variability. The grain texture analysis shows that the majority of samples fall in the brackets of clayey silt; silty sand; and sand, silt, and clay. Common mineral components associated with these are quartz, feldspar, clay minerals, etc. The range for the mean grain size lies between 3Φ to 9Φ(Φ is diameter of the sediments) where most of the grain size distributions are symmetrically to fine symmetrically skewed, indicating intermediate energy to adjust to environmental conditions. The granulometric and physicochemical characteristics of the sediment samples also indicate the directional distribution pattern of sediment along the hydrological pathway. Future studies concentrating on the fluvial discharges of water and sediment will be highly insightful in reconstructing the past net sediment accumulation processes in the Baraila Wetland.

关键词： Grain size analysis Hydrodynamic energy Mineralogy Allogenic source Terrigenous input Wetland

Review on hepatitis B virus precore/core promoter mutations and their correlation with genotypes and liver disease severity

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World Journal of Hepatology 2022年第4期14卷 708-718页

作者： rajesh kumar Department of School Education Haryana GovernmentPanchkula 134109HaryanaIndia

Of 350 million people worldwide are chronically infected with hepatitis B virus(HBV)and are at risk of developing cirrhosis and hepatocellular carcinoma(HCC)later in *** is the most diverse DNA virus,and its genome is composed of four open reading frames:Presurface antigen/surface antigen gene(preS/S),precore/core gene(preC/C),polymerase gene(P),and theχgene(χ).HBV produces quasispecies naturally or in response to antiviral agents because of the absence of proofreading activity amid reverse transcription and a high replication *** virus has 10 genotypes(A to J)with different geographical *** are various HBV mutations in the HBV genome,including preC/C mutations,preS/S mutations,P gene mutations,andχgene *** core promoter region plays a vital part in the replication,morphogenesis and pathogenesis of the *** precore region also plays a crucial role in viral *** core promoter and precore mutations rescue the virus from host immune surveillance and result in the formation of mutated strains that may have altered ***/C mutations are associated with liver disease *** mutations stop hepatitis B e antigen(HBeAg)production and basal core promoter mutations downregulate HBeAg *** in the basal core promoter are also associated with increased HBV replication and an increased incidence of advanced liver diseases such as cirrhosis and *** emergence of antiviral-resistant mutations is the main reason for treatment *** review focuses mainly on preC/C promoter mutations and their correlation with genotypes and liver disease *** perception and knowledge of HBV genetic variety and mutants could be vital to discover techniques for the prognosis and control of HBV infection.

关键词： Hepatitis B virus Hepatitis B virus e antigen Hepatocellular carcinoma Basal core promoter Core promoter region Precore region Fulminant hepatitis Acute hepatitis

Zinc Oxide Nanostructures for NO_2 Gas–Sensor Applications:A Review

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Nano-Micro Letters 2015年第2期7卷 97-120页

作者： rajesh kumar O.Al-Dossary Girish kumar Ahmad Umar PG Department of Chemistry JCDAV College Department of Physics King Saud University Department of Chemistry Faculty of Arts and Sciences Najran University Promising Centre for Sensors and Electronic Devices (PCSED) Najran University

Because of the interesting and multifunctional properties,recently,ZnO nanostructures are considered as excellent material for fabrication of highly sensitive and selective gas ***,ZnO nanomaterials are widely used to fabricate efficient gas sensors for the detection of various hazardous and toxic *** presented review article is focusing on the recent developments of NO2gas sensors based on ZnO *** review presents the general introduction of some metal oxide nanomaterials for gas sensing application and finally focusing on the structure of ZnO and its gas sensing *** gas sensing characteristics such as gas response,response time,recovery time,selectivity,detection limit,stability and recyclability,etc are also discussed in this ***,the utilization of various ZnO nanomaterials such as nanorods,nanowires,nano-micro flowers,quantum dots,thin films and nanosheets,etc for the fabrication of NO2gas sensors are also ***,various factors such as NO2concentrations,annealing temperature,ZnO morphologies and particle sizes,relative humidity,operating temperatures which are affecting the NO2gas sensing properties are discussed in this ***,the review article is concluded and future directions are presented.

关键词： ZnO nanostructure Gas sensors Sensor parameters Sensor mechanism

Adaptive relay co-ordination using a busbar splitting approach for a system integrity protection scheme

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Protection and Control of Modern Power Systems 2022年第1期7卷 189-200页

作者： rajesh Saikrishna Nilesh kumar Rajalwal Debomita Ghosh Birla Institute of Technology Mesra Ranchi India

Power system faults can often result in excessively high *** sustained for a long time,such high currents can damage system ***,it is desirable to operate the relays in the minimum possible *** this paper,a busbar splitting approach is used for adaptive relay setting and co-ordination purposes for a system integrity protec-tion scheme(SIPS).Whenever a fault occurs,the busbar splitting scheme splits a bus to convert a loop into a radial *** splitting schemes are chosen such that the net fault current is also *** splitting elimi-nates the dependency upon minimum breakpoints set(MBPS)and reduces the relay operating time,thus making it *** proposed methodology is incorporated into the IEEE 14-bus and IEEE 30-bus systems with single and multiple fault *** modeling and simulation carried out in ETAP,and the results of the proposed busbar splitting-based relay co-ordination are compared with the MBPS splitting-based relay co-ordination.

关键词： System integrity protection scheme(SIPS) Relay co-ordination Minimum breakpoint set(MBPS) Ward equivalent method Busbar splitting Wide area monitoring system(WAMS) ETAP

Bamboo resources of Sikkim Himalaya: diversity, distribution and utilization

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Journal of Forestry Research 2014年第4期25卷 929-934页

作者： Deo kumar Tamang Dinesh Dhakal D. G. shrestha Sikkim State Remote Sensing Application Centre Sikkim State Council of Science and Technology Development Area Gangtok 737101 Sikkim

We recorded 8 genera and over 30 species of bamboo in Sikkim of the reported 23 genera and 125 species in Indi＆ Thirty percent of bamboo species were recorded in tropical forests （0-900 m）, 40% of species in sub-tropical forests （900-1,800 m）, 17% of species in temper- ate forests （1,800-2,700 m）, 9% of species in sub-alpine forests （2,700-3,500 m） and 4% of species in alpine vegetation （3,500-4,500 m）. Bamboo is used for various purposes and its versatility qualifies it to be a multiple-use alternative to timber, food for villagers and for tribal in particular. Bamboo is also equally important to Red Panda （Ailurusful- gens）, the state animal of Sikkim. We develop a list of bamboos occur- ring in Sikkim with their vernacular names, distributions and uses in the Himalayan state. However, more extensive study is required to fully describe the bamboo diversity of the Himalayan state.

关键词： bamboo Dendrocalamus diversity uses Sikkim

Determining bioclimatic space of Himalayan alder for agroforestry systems in Nepal

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Plant Diversity 2018年第1期40卷 1-18页

作者： Santosh kumar Rana Hum Kala Rana Krishna kumar shrestha Suresh Sujakhu Sailesh Ranjitkar Key Laboratory{or Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Systematics and Biodiversity Unit Central Department of BotanyTribhuvan UniversityKirtipurKathmanduNepal jade Consult Private Limited KabilmargThapathaliKathmanduPOB 746Nepal World Agroforestry Centre East and Central Asia 132 Lanhei RdHeilongtanKunmingChina

Himalayan alder species are proven to be very useful in traditional as well as contemporary agroforestry practice. These nitrogen-fixing trees are also useful in the land restoration. Therefore, understanding the distribution of Himalayan alder and the potential zone for plantation is meaningful in the agroforestry sector. Suitable climatic zones of Alnus spp. were modelled in Max Ent software using a subset of least correlated bioclimatic variables for current conditions(1950 -2000), topographic variables(DEM derived) and Landuse Landcover(LULC) data. We generated several models and selected the best model against random models using ANOVA and t-test. The environmental variables that best explained the current distribution of the species were identified and used to project into the future. For future projections, ensemble scenarios of climate change projection derived from the results of 19 Earth System Models(ESM) were used. Our model revealed that the most favorable conditions for Alnus nepalensis are in central Nepal in the moist north-west facing slope, whereas for Alnus nitida they are in western *** major climatic factor that contributes to Alnus species distribution in Nepal appears to be precipitation during the warmest quarter for A. nepalensis and precipitation during the driest quarter for A. nitida. Future projections revealed changes in the probability distribution of these species, as well as where they need conservation and where they can be planted. Also, our model predicts that the distribution of Alnus spp. in hilly regions will remain unchanged, and therefore may represent sites that can be used to revitalize traditional agroforestry systems and extract source material for land restoration.

关键词： Alder Agroforestry Species distribution modeling Climate change MaxEnt

Predicting the impact of climate change on the distribution of two threatened Himalayan medicinal plants of Liliaceae in Nepal

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Journal of Mountain Science 2017年第3期14卷 558-570页

作者： RANA Santosh kumar RANA Hum Kala GHIMIRE Suresh Kulllar shrestha Krishna kumar RANJITKAR Sailesh Key Laboratory for Plant Diversity and Biogeography of EastAsia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Central Department of Botany Tribhuvan UniversityKirtipurKathmanduNepal World Agroforestry Centre East and Central Asia 132 Lanhei RdHeilongtanKunming 650201China

Predicting the potential distribution of medicinal plants in response to climate change is essential for their conservation and management. Contributing to the management program, this study aimed to predict the distribution of two threatened medicinal plants, Fritillaria cirrhosa and Lilium nepalense. The location of focal species gathered from herbarium specimen housed in different herbaria and online databases were geo-referenced and checked for spatial autocorrelation. The predictive environmental variables were selected, and MaxEnt software was used to model the current and future distributions of focal species. Four Representative Concentration Pathway （RCP） trajectories of the BCC-CSMI.1 model were used as the future （2050） projection layer. The MaxEnt modelling delineated the potential distribution of F. cirrhosa and L. nepalense. The current suitability is projected towards Central and Eastern Hilly/Mountainous regions. Both species gain maximum suitability in RCP 4.5 which decline towards other trajectories for L. nepalense. Overall, both the focal species shift towards the north-west, losing their potential habitat in hilly and lower mountainous regions by 2050 across all trajectories. Our results highlight the impact of future climate change on two threatened and valuable species. The results can be further useful to initiate farming of these medicinally and economically important species based on climatically suitable zone and for designing a germplasm conservation strategy.

关键词： Commercial exploitation Conservation Lily Fritillaria cirrhosa Lilium nepalense MaxEntmodelling Species distribution

Bibliometric analysis of Blockchain in the healthcare domain

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Intelligent and Converged Networks 2023年第4期4卷 305-312页

作者： Shilpi Garg rajesh kumar Kaushal Naveen kumar Anshul Verma Chitkara Institute of Engineering and Technology Chitkara UniversityPunjab 140401India Institute of Science Banaras Hindu UniversityVaranasi 221005India

As an innovation,Blockchain has transformed numerous industries and sparked the interest of the research community due to its abundance of benefits,opening up diverse research routes in the healthcare sector in the last *** Health 4.0 becoming ubiquitous in the healthcare industry,end-user transactions are being carried out on a decentralized network,making Blockchain profitable to meet the demands of the modern healthcare ***,a detailed analysis of Blockchain is very *** study emphasizes the evolution of science and the preliminary research of Blockchain in healthcare through bibliometric *** the data are extracted from the Scopus database,and the VOSviewer tool is used for analysis.A total of 1152 Scopus articles published between 2018 and 2022 are *** reveal that in 2022,the field of Blockchain experienced a notable increment in the number of publications and a significant growth *** Access became well known in this field and had a large number of *** is observed that China and India are the leading countries in terms of publications on *** study offers a number of recommendations that amateur and professional researchers can use as a benchmark before commencing a Blockchain investigation in the future.

关键词： Blockchain bibliometric healthcare VOSviewer

Evaluation of phytochemical and antioxidant activities of the different fractions of Hybanthus enneaspermus (Linn.) ***. (Violaceae).

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Asian Pacific Journal of Tropical Medicine 2011年第5期4卷 391-396页

作者： Dinesh kumar Patel rajesh kumar Damiki Laloo Siva Hemalatha Pharmacognosy Research Laboratory Department of PharmaceuticsInstitute of TechnologyBanaras Hindu UniversityVaranasi-221005.India

Objective:To investigate the naturally occurring antioxidant for the first time from the different solvent fractions of Hybanthus enneaspermus（***） Linn ***（Violaceae）. Methods:Different fractions of *** were tested for total phenolic content,and in vitro antioxidant activity was measured by total antioxidant assay,DPPH assay,reducing power, nitric oxide（NO）,hydrogen peroxide（H2O2） scavenging ***:The ethyl acetate（EA） fraction was found to have high levels of phenolic content[（212.15±0.79） mg GAE/g].The EA fraction exhibited higher total antioxidant capacity,higher percentage of DPPH radical scavenging activity[（127.07±2.29） Fg/mL],nitric oxide[（245.16±1.44）μg/mLJ,hydrogen peroxide[（227.38±7.18）μg/mL],deoxyribose[（270.61±8.72）μg/mL]and higher reducing *** was a significant correlation between total phenolic content and total antioxidant activity（r =0.972）. Conclusions:These results reveal that EA fraction of *** has strong antioxidant potential compared with other *** further study has been extended to the isolation of the possible compound that is responsible for having antioxidant property.

关键词： Hybanthus enneaspermus Antioxidant Total phenolics