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Journal of Forestry Research 2012年第1期23卷 53-63页

作者： Sumeet Gairola c.m.sharma S.K.Ghildiyal Sarvesh Suyal Department of Botany Post Box No.51HNB Garhwal UniversitySrinagar Garhwal-246174Uttarakhand India

The present study was undertaken in moist temperate forest of mandal-chopta area in the Garhwal region of Uttarakhand, India. The aim of the present study was to understand the regeneration dynamics of the dominant tree species along an altitudinal gradient in naturally regen- erating, restricted access forest. The overall regeneration status was fairly high in the study area. most of the native canopy and undercanopy domi- nants had frequent reproduction and expanding populations, which sug- gests the stability of forest structure/composition and further expansion of dominant species. The overall regeneration of trees in the forest had a greater contribution of middle and understurey species. Because of infre- quent rep＇roduction and declining populations of some of the dominant native species viz., Abies pindrow, Alnus nepalensis and Betula alnoides, structural/compositional changes in the future are expected in respective forests dominated by them..4bies pindrow and Taxus baccata need im- mediate attention by forest managers for their survival in the area. Seed- lings were found to be more prone to competition from herb and shrubs than saplings.

关键词： Garhwal environmental gradient forest structure regenera-tion curves species diversity

Effects of slope aspects on forest compositions, community structures and soil properties in natural temperate forests of Garhwal Himalaya

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Journal of Forestry Research 2010年第3期21卷 331-337,398页

作者： c.m.sharma N.P.Baduni Sumeet Gairola S.K.Ghildiyal Sarvesh Suyal Department of Botany Post Box No.51HNB Garhwal University

The present study was undertaken in seven natural forest types of temperate zone （1500 to 3100 m, a.s.l.） of Garhwal Himalaya to understand the effects of slope aspects viz., north-east （NE）, north-west （NW）, south-east （SE） and south-west （SW）, on the forest structure, composition and soil characteristics of each selected forest type. The sample plots in each forest type were laid out by using stratified random approach. The indices i.e., the Importance Value Index, Shannon-Wiener diversity index, Simpson’s concentration of Dominance, Simpson diver-sity index, Pielou equitability and margalef species richness index were calculated statistically using standard softwares to elucidate the differ-ences in forest structure and composition of forest types on different slope aspects of the sites. The composite soil samples were taken from each forest stand and the physico-chemical properties of the soil i.e., moisture content （mc）, water holding capacity （WHc）, pH, organic carbon （Oc）, phosphorus （P）, potassium （K） and available nitrogen （N） were analyzed. The results show that the higher values of total basal cover （74.4 m2·ha-1 in Quercus semecarpifolia forest）, concentration of dominance （0.85 in Pinus roxburghii forest） and Tree diversity （1.81 in Quercus floribunda forest） in the forests were recorded in the northern aspects. mc （40.8% in Quercus leucotrichophora forest）, WHc （48.9% in cupressus torulosa forest）, Oc （3.8% in cedrus deodara forest）, P （31.9 kg·ha-1 in Quercus leucotrichophora forest） and N （1.0% in Pinus roxburghii forest） had also higher values in the soils of northern aspects. consequently the higher productivity of the forests was also noticed on the northern aspects.

关键词： diversity stem density forest composition aspects soil nutrients

A unified fractional flow framework for predicting the liquid holdup in two-phase pipe flows

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Petroleum Science 2024年第4期21卷 2614-2624页

作者： Fuqiao Bai Yingda Lu mukul m.sharma Hildebrand Department of Petroleum and Geosystems Engineering The University of Texas at Austin

Two-phase pipe flow occurs frequently in oil & gas industry, nuclear power plants, and ccUS. Reliable calculations of gas void fraction(or liquid holdup) play a central role in two-phase pipe flow models. In this paper we apply the fractional flow theory to multiphase flow in pipes and present a unified modeling framework for predicting the fluid phase volume fractions over a broad range of pipe flow conditions. compared to existing methods and correlations, this new framework provides a simple,approximate, and efficient way to estimate the phase volume fraction in two-phase pipe flow without invoking flow patterns. Notably, existing correlations for estimating phase volume fraction can be transformed and expressed under this modeling framework. Different fractional flow models are applicable to different flow conditions, and they demonstrate good agreement against experimental data within 5% errors when compared with an experimental database comprising of 2754 data groups from 14literature sources, covering various pipe geometries, flow patterns, fluid properties and flow *** gas void fraction predicted by the framework developed in this work can be used as inputs to reliably model the hydraulic and thermal behaviors of two-phase pipe flows.

关键词： Pipe fractional flow Liquid holdup multiphase pipe flow Gas void fraction

Sequential decay analysis of^(235)U(n^(th),f)reaction using fragmentation approach

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chinese Physics c 2024年第6期48卷 145-154页

作者： Nitin sharma Ashutosh Kaushik manoj K.sharma School of Physics and materials Science Thapar Institute of Engineering&TechnologyPatiala-147004PunjabIndia

Numerous experimental and theoretical observations have concluded that the probability of the three fragment emission(ternary fission)or binary fission increases when one proceeds towards the heavy mass region of nuclear periodic *** factors affect fragment emission,such as the shell effect,deformation,orientation,and fissility *** and ternary fissions are observed for both ground and excited states of the *** collinear cluster tripartition(ccT)channel of the^(235)U(n^(th),f)reaction is studied,and we observe that the ccT may be a sequential or simultaneous emission *** date,different approaches have been introduced to study the ccT process as a simultaneous or sequential process,but the decay dynamics of these modes have not been not fully *** the three fragments of the sequential process and exploring their related dynamics using an excitation energy dependent approach would be of further ***,in this study,we investigate the sequential decay mechanism of the^(235)U(n^(th),f)reaction using quantum mechanical fragmentation theory(QmFT).The decay mechanism is considered in two steps,where initially,the nucleus splits into an asymmetric *** the second step,the heavy fragment obtained in the first step divides into two *** I analysis is conducted by calculating the fragmentation potential and preformation probability for the spherical and deformed choices of the decaying *** most probable fragment combination of stage I are identified with respect to the dips in the fragmentation structure and the corresponding maxima of the preformation probability(P0).The light fragments of the identified decay channels(obtained in step I)agree closely with the experimentally observed *** excitation energy of the decay channel is calculated using an iteration *** excitation energy is shared using an excitation energy dependent level density *** obtained excitation

关键词： fission cluster radioactivity ternary fission spontaneous fission cluster model total kinetic energy preformation probability

Study of plasma parameters of coaxial plasma source using triple Langmuir probe and Faraday cup diagnostics

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Plasma Science and Technology 2024年第4期26卷 94-100页

作者： Sunil KANcHI Rohit SHUKLA Archana sharma Pulsed Power and Electromagnetics Division Bhabha Atomic Research CentreVisakhapatnam 531011India Homi Bhabha National Institute Mumbai 400085India Beam Technology Development Group Bhabha Atomic Research CentreMumbai 400085India

coaxial plasma guns are a type of plasma source that produces plasma which propagates radially and axially controlled by the shape of the ground electrode, which has attracted much interest in several applications. In this work, a 120° opening angle of cPG nozzle is used as a plasma gun configuration that operates at the energy of 150 J. The ionization of polyethylene insulator between the electrodes of the gun produces a cloud of hydrogen and carbon *** triple Langmuir probe and Faraday cup are used to measure plasma density and plasma temperature. These methods are used to measure the on-axis and off-axis plasma divergence of the coaxial plasma gun. The peak values of ion densities measured at a distance of 25 mm on-axis from the plasma gun are(1.6±0.5)×10^(19)m^(-3)and(2.8±0.6)×10^(19)m^(-3)for hydrogen and carbon plasma respectively and the peak temperature is 3.02±0.5 eV. The mean propagation velocity of plasma is calculated using the transit times of plasma at different distances from the plasma gun and is found to be 4.54±0.25 cm/μs and 1.81±0.18 cm/μs for hydrogen and carbon plasma respectively. The Debye radius is obtained from the measured experimental data that satisfies the thin sheath approximation. The shot-to-shot stability of plasma parameters facilitates the use of plasma guns in laboratory experiments. These types of plasma sources can be used in many applications like plasma opening switches, plasma devices, and as plasma sources.

关键词： coaxial plasma source triple Langmuir probe Faraday cup plasma density plasma temperature

Insight into metabolomic Profiling of Tinospora cordifolia: Recent Advances and Future Perspectives of Quality control

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World Journal of Traditional chinese medicine 2024年第2期10卷 137-148页

作者： Atiqul Islam c.Anurag Nazia Siddiqui Xianting Ding Alok sharma college of Pharmacy JSS Academy of Technical EducationNoidaUttar PradeshIndia Department of Pharmaceutical Technology MIETMeerutUttar PradeshIndia Institute for Personalized medicine School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina

The objective of this study was to offer a review of previous works on Tinospora cordifolia(Tc) metabolomics with a highlight on the use of metabolomics in comparative evaluations between varieties and selection of optimum cultivation, collection, and extraction procedures, providing insights into pharmaceutical and food product quality monitoring. Scholarly databases were searched to gather relevant information on Tc's therapeutic usefulness, phytoconstituent studies, metabolomics, and applications. Pub chem was used to learn the structures of several of the metabolites. The various medicinal properties of Tc were extensively researched. The most essential portions of the plant in Ayurvedic medicines are the stems. Bioactive phytochemicals such as steroidal lactones, alkaloids, diterpenoids, and phenolic compounds are present in the roots and leaves. metabolomic analysis revealed that, in addition to the season and geographical region of the sample collected, the metabolite profiles of Tc also depend on the parts of the plant taken as a sample and also the plant's stage of growth. The amounts of secondary metabolites differed between morpho/chemotypes within the Tc species. Despite the fact that research on Tc began several decades ago, the diversity of phytoconstituents was not appreciated because of a lack of reliable techniques for phytochemical fingerprinting. The uncovering of several novel metabolites was aided by advances in chromatography combined with mass spectrometry. To produce a full metabolomic profile, researchers used mutually complementary techniques. Following that, data analysis and searches against spectrum databases allowed for signal annotation and interpretation of metabolites in large quantities without separating them separately. The current review includes a critical assessment of metabolomic data and an overview of the technique's various applications. It is vital to establish the metrics of quality control of herbal medicines in order to

关键词： Analytical tools metabolomics quality control secondary metabolites Tinospora cordifolia

microRNA-502-3p regulates GABAergic synapse function in hippocampal neurons

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Neural Regeneration Research 2024年第12期19卷 2698-2707页

作者： Bhupender sharma melissa mTorres Sheryl Rodriguez Laxman Gangwani Subodh Kumar center of Emphasis in Neuroscience Department of Molecular and Translational MedicinePaul L.Foster School of MedicineTexas Tech University Health Sciences CenterEl PasoTXUSA Bond Life Sciences center and Department of Veterinary Pathobiology University of MissouriColumbiaMOUSA L.Frederick Francis Graduate School of Biomedical Sciences Texas Tech University Health Sciences CenterEl PasoTXUSA

Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's disease-related *** previous study identified the upregulation of microRNA-502-3p(miR-502-3p)and downregulation of GABA type A receptor subunitα-1 in Alzheimer's disease *** study investigated a new molecular relationship between miR-502-3p and GABAergic synapse *** vitro studies were perfo rmed using the mouse hippocampal neuronal cell line HT22 and miR-502-3p agomiRs and *** silico analysis identified multiple binding sites of miR-502-3p at GABA type A receptor subunitα-1 *** assay confirmed that miR-502-3p targets the GABA type A receptor subunitα-1 gene and suppresses the luciferase ***,quantitative reve rse transcription-polymerase chain reaction,miRNA in situ hybridization,immunoblotting,and immunostaining analysis confirmed that overexpression of miR-502-3p reduced the GABA type A receptor subunitα-1 level,while suppression of miR-502-3p increased the level of GABA type A receptor subunitα-1 ***,as a result of the overexpression of miR-502-3p,cell viability was found to be reduced,and the population of necrotic cells was found to be *** whole cell patch-clamp analysis of human-GABA receptor A-α1/β3/γ2L human embryonic kidney(HEK)recombinant cell line also showed that overexpression of miR-502-3p reduced the GABA current and overall GABA function,suggesting a negative correlation between miR-502-3p levels and GABAergic synapse ***,the levels of proteins associated with Alzheimer s disease were high with miR-502-3p overexpression and reduced with miR-502-3p *** present study provides insight into the molecular mechanism of regulation of GABAergic synapses by *** propose that micro-RNA,in particular miR-502-3p,could be a potential the

关键词： Alzheimer's disease GABAergic synapse gamma-aminobutyric acid type A receptor subunitα-1(GABRα1) microRNA-502-3p(miR-502-3p) miRNA in situ hybridization Patch-clamp

Numerical Analysis of Phase change and container materials for Thermal Energy Storage in the Storage Tank of Solar Water Heating System

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Journal of Thermal Science 2024年第2期33卷 408-421页

作者： SINGH Shailendra ANAND Abhishek SHUKLA Amritanshu sharma Atul Non-conventional Energy Laboratory Rajiv Gandhi Institute of Petroleum TechnologyJais Amethi229304India

This study evaluates the effectiveness of phase change materials(Pcms) inside a storage tank of warm water for solar water heating(SWH) system through the theoretical simulation based on the experimental model of *** et *** model is explained by five fundamental equations for the calculation of various parameters like the effectiveness of Pcms,the mass of hot water,total heat content,and duration of *** study simulated eleven Pcms to analyze their effectiveness like Sodium hydrogen phosphate dodecahydrate(SHPD),Om 37,N-Eicosane(NE),Lauric acid(LA),Paraffin wax(PW),Om 48,Paraffin wax c_(20-33)(PW-c20-33),Sodium acetate trihydrate(SAT),Palmitic acid(PA),myristic acid(mA),and Stearic acid(SA).Among all Pcms,the SHPD has found the highest value of effectiveness factor of ***,it is the most recommended Pcm for the storage tank of the SWH *** study also includes the melt fraction analysis of all enumerated Pcms corresponding to container materials of stainless steel,glass,aluminum mixed,tin,aluminum,and *** melt fraction analysis is performed by making a coding program in the FORTRAN programming *** the analysis,copper container material is found to have high melting rate for all Pcms so it is superior to other container materials.

关键词： theoretical model solar water heating system phase change material effectiveness factor melt fraction

Exploring one material for dual applications:A red-emitting mg2GeO4:Eu3+ nanophosphor for future generation energy efficient WLEDs and dosimetric applications

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Journal of Rare Earths 2024年第10期42卷 1835-1845页

作者： Akshay Arjun G.P.Darshan S.c.sharma H.Nagabhushana D.V.Sunitha H.B.Premkumar Department of Physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied Sciences Jain University c.N.R.Rao centre for Advanced materials Tumkur University School of Applied Sciences (Physics) REVA University

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a Puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was estimated and obtained to be～4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at ～579,589,610,661,and 707 nm,which are due to characteristic5D0→7F0,5D0→7F1,5Do→7F2,5D0→7F3and5D0→7F4transitions of Eu3+ions,*** commission International de L'Eclairage color coordinates are gradually tuned from pale red（0.5980,0.4012） to a pure red（0.6385,0.3611） *** glow peaks showcase excellent super-linear response at low doses of γ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes（WLEDs） and personal dosimetric applications.

关键词： Dosimetry Nanophosphors Photoluminescence Photometric properties Rare earths Thermoluminescence

Role of Social capital in Determining Happiness and Life Satisfaction:mediation of Self-reported Health Using Path Analysis

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Fudan Journal of the Humanities and Social Sciences 2024年第2期17卷 211-242页

作者： Suraj sharma Department of Economics S.M.(P.G.)CollegeChandausiM.J.P.Rohilkhand UniversityBareilly243006India

This study links social capital with people’s health and well-being using data from the seventh wave of the World Value Survey,logistic regression,and path *** study’s findings show that happiness and life satisfaction are two different measures of the same construct,or *** determinants of each are also characterised differently:while life satisfaction is more of a stable and relative measure and is more strongly influenced by civic cooperation,social participation,and educational attainment,happiness is more of an unstable measure and is more strongly influenced by community belonging,trust and confidence aggregates,including employment and location of residence of an ***,freedom of choice,financial satisfaction or social comparison,and state of health were the most important factors influencing happiness and life *** findings also show that self-reported health(SRH)has a greater impact on happiness than a measure of life *** analysis shows out of the three other components of social capital—community belonging,civic engagement,and social participation—trust and confidence aggregates are the ones that have the biggest impact on increased social *** both well-being measures,SRH mediated the *** life satisfaction measure had a higher level of mediation of SRH than happiness,but social capital had a smaller direct impact on life satisfaction than on *** was found to be partially mediating this relationship for both happiness and life satisfaction measures,which means that people with higher social capital reported feeling better off.

关键词： Happiness Health Life satisfaction Path analysis Social capital