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Patterns of species dominance, diversity and dispersion in ‘Khasi hill sal' forest ecosystem in northeast India

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Forest Ecosystems 2014年第4期1卷 227-246页

作者： Amit Kumar tripathi Uma Shankar Department of Botany North-Eastern Hill University

Background： The ＇Khasi hill sal＇ forest ecosystem in Meghalaya, India represents the easternmost limit of sal distribution. We tested if tree diversity and compositional heterogeneity of this ecosystem was higher than other sal-dominated forests due to moister environment. Methods： Vegetation was sampled in 11 transects of 10 m width and up to 500 m length covering 5.2 ha area. All stems ≥10 cm girth at breast height were enumerated. Results： We found a pattern of mixed dominance of Shored robusta （sal） and Schima wollichii and co-dominance of Pinus kesiyo and Careya arborea. The Shannon＇s diversity index （H＇） was 3.395 nats. This value is remarkably high and competitive to that of moist sal forests of eastern Himalayan foothills and sal-dominated forests of Tripura. A high value of H＇ was manifested by： a） high species richness （S = 123）, b） good equitability （70.6%）, c）＇fair＇ resource apportionment, and d） abundance of rare species （84% species with less than one per cent of total individuals, 67% species with two or less individuals ha-1 and 59% species with one or less individuals ha-1）. The compositional heterogeneity was ＇fair＇（Whittaker＇sβw = 3.15）. The presence of Fagaceae with six species commanding 4.3% of importance value （IVl） and of a pine （P. kesiya） in sal forest was remarkable. As many as 58 species showed ＇low density （〈 10 individuals ha-1）, uniform dispersion＇, five species achieved ＇higher density （〉 10 individuals ha-l）, uniform dispersion＇ and six of the top 10 species were ＇clumped＇. The forest showed an exponential demographic curve illustrating ＇good＇ regeneration of an expanding community. Vertical stratification was simple with a poor canopy and fair subcanopy, which together with low basal area （15.65 m2 . ha-1 for individuals ≥ 10 cm gbh） indicated logging of mature sal trees in the past. Conclusions： The ＇Khasi hill sal＇ forest ecosystem is richer in alpha and beta diversity than most sal-dominated forests, but past logging has reduce

关键词： Forest structure Phytosociology Floristics Beta diversity Abundance Species dispersion Populationstructure Regeneration Shorea robusto

Effect of forest fragment size on tree diversity and population structure of humid subtropical forest of Meghalaya, India

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生物多样性 2010年第2期18卷 208-214页

作者： Om Prakash tripathi Khongjee Rangdajied Reynald Department of Botany North Eastern Hill University Shillong-793 022 India Department of Forestry NERIST Nirjuli-791109 India

The present study was conducted in subtropical humid forests of Meghalaya to study the distributional pattern of species, floristic composition, community structure and tree population *** fragments of varying sizes(0.5 ha, 1 ha, 2 ha and 5 ha) were used in the *** of the forest fragments are distributed within the same altitudinal range, and had similar rainfall and temperature *** forest fragments were sampled using random quadrats to analyze the impact of fragment size on tree diversity and population *** were used to compare the dispersion pattern of plant species, species diversity among fragments, and the heterogeneity and homogeneity of the fragments.A total of 45 tree species were recorded from all the fragments and simple correlation showed that the species richness was positively related to fragment size(n = 4, P<0.05).Other measures such as stand density, basal cover, diversity and dominance indices were unrelated to fragment *** canopy was composed mainly of Castonopsis indica, ***, Schima khasiana and Engelhardtia spicata in all of the fragments.A majority of woody tree species were contagiously distributed which made the forest community highly patchy in *** values of Sorensen's similarity index and high values of Whittaker's β-diversity index between the fragments suggest marked difference in the species composition among the *** maximum stand density, basal area, Shannon diversity index and Simpson dominance index was recorded in a 5-ha *** in lower girth classes(15-55 cm circumference at breast height, CBH) accounted for 52-86% of stand density in all fragments except in 0.5-ha fragments where middle girth class(55-95 cm CBH) accounted for 47% of the total stand *** overall density of seedlings, saplings and adult trees formed a pyramidal structure, indicating that the period between the sapling and adult stage was a critical stage in tree life cycles, as the

关键词：生物多样性相异性指数生态学森林

Current concepts in the management of non-cirrhotic non-malignant portal vein thrombosis

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World Journal of Hepatology 2024年第5期16卷 751-765页

作者： Adam J Willington Dhiraj tripathi Department of Hepatology University Hospitals Birmingham NHS Foundation TrustBirmingham B152GWUnited Kingdom Department of Hepatology University Hospitals BirminghamBirmingham B152THUnited Kingdom

Non-cirrhotic non-malignant portal vein thrombosis(NCPVT)is an uncommon condition characterised by thrombosis of the portal vein,with or without extension into other mesenteric veins,in the absence of cirrhosis or intra-abdominal *** can include intestinal infarction,variceal bleeding and portal *** this article,we address current concepts in the management of NCPVT including identification of risk factors,classification and treatment,and review the latest evidence on medical and interventional management options.

关键词： Non-cirrhotic portal vein thrombosis Portal vein Mesenteric veins Venous thrombosis Portal hypertension

Is Regular Probiotic Practice Safe for Management of Sepsis?

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Chinese Journal of Integrative Medicine 2022年第2期28卷 185-192页

作者： Rishabh Kumar Alok Shiomurti tripathi Nidhi Sharma Gaaminepreet Singh Lucy Mohapatra Department of Pharmacology ISF College of PharmacyMoga(Punjab)India Department of Pharmacology Amity Institute of PharmacyAmity UniversityLucknow(UP)India

For decades,the gut has been thought to play an important role in sepsis *** is a serious life-threatening,chronic condition of an infection caused by dysregulated host immune response in most of the intensive care unit *** have dual roles in polymicrobial sepsis *** may induce sepsis in many cases and may prevent its prognosis in many *** evidence from both pre-clinical and clinical studies have demonstrated that probiotic therapy ameliorates various inflammatory mediators such as tumor necrosis factor,interleukin-10(IL-10),IL-6,etc.,in *** addition,probiotic use was also found to reduce the severity of pathological conditions associated with irritable bowel disorder and prevent development of endocarditis in *** contrary,probiotic therapy in neonatal and athymic adult mice fail to provide any beneficial effects on mortality and sepsis-induced ***,in few clinical trials probiotic use was found to aggravate sepsis by promoting inflammatory cascade rather than suppressing *** review discusses various studies regarding the beneficial or harmful effects associated with probiotic therapy in sepsis.

关键词： sepsis probiotics microbial flora immune system

Toxicity of copper oxide nanoparticles on agriculturally important soil rhizobacteria Bacillus megaterium

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Emerging Contaminants 2024年第1期10卷 139-147页

作者： Gyan Datta tripathi Zoya Javed Kavya Dashora Agri-Nanotechnology Laboratory Centre for Rural Development and TechnologyIndian Institute of Technology DelhiNew Delhi110016India

Copper oxide nanoparticles are an integral part of modern agrochemical industries,such as pesticides and nano *** has been extensively reviewed and reported that the interaction of nanoparticles with plant growth-promoting rhizobacteria(PGPRs)may be toxic due to their accumulation in the soil and may remain in contact for a long time which causes a negative impact on the soil microbial *** study presented here,investigates the impact of the copper oxide nanoparticles on the isolated PGPR species Bacillius megaterium AGNTL MM7 in invitro *** observed that the formation of Reactive Oxygen Species(ROS)at¼of Minimum Inhibitory Concentrations(MIC)of CuO nanoparticles resulted in a decrease in the Indole Acetic Acid(IAA)production(83.02μg/ml)as the marker of the nanoparticles mediated stress on the Bacillus megaterium AGNTL *** minimum inhibitory concentration(MIC)assay was observed at 4 mg/*** solubility of CuO nanoparticles was 0.014%and the Nanotracking analyzer estimated the mean average size 188 nm in a liquid medium such as *** Electron Microscopic(TEM)studies observed that the concentration of 1 mg/ml nanoparticles showed a strong affinity with cell envelope and caused a significant negative impact on the microorganism,resulting in 58%inhibition in IAA production was observed in comparison to the control i.e.,197.8μg/*** flow cytometric analysis also significantly validated the toxicity at the same concentration.

关键词： Contact mode toxicity Dissolution Oxidative stress Cellular membrane Plant growth promotion

A role of computer vision in fruits and vegetables among various horticulture products of agriculture fields: A survey

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Information Processing in Agriculture 2020年第2期7卷 183-203页

作者： Mukesh Kumar tripathi Dr.Dhananjay D.Maktedar Department of CSE Guru Nanak Dev Engineering CollegeBidarKarnatakaIndia

Computer vision is a consistent and advanced technique for image processing,with the propitious outcome,and enormous potential.A computer vision has been strongly adopted in the heterogeneous domain including *** the study of existing research on the role of computer vision in fruits and vegetables among various horticulture products of agriculture fields it is noticed that,the existing survey paper has not focused properly on mathematical framework,feature descriptor,defect detection on multiple datasets of fruits and vegetables *** has motivated us to undertake an extensive *** this paper,we examine the paper broadly related to fruits and vegetables among various horticulture products of agriculture fields,specific model,data pre-processing,data analysis method and overall value of performance accuracy by using a particular performance ***,we study the different type of disease present in various fruit and *** have also focused on the comparison of different machine learning approach with respect to different performance metrics on the same ***,we have found that among all existing machine learning techniques SVM give better classification accuracy.A generalized framework to grade the quality and defect detection of multiple fruits and vegetables is also proposed in this *** paper covers the survey of ninety-eight papers closely related to computer vision in the agricultural *** the survey,we have found that computer vision plays an important role and has a large potential to address the challenges related to the agricultural fields.

关键词： Computer vision Agriculture Survey Pre-processing Descriptor Data-analysis Defect detection Monitoring

Analysis of structural,optical and electrical properties of metal/p-ZnO-based Schottky diode

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Journal of Semiconductors 2017年第10期38卷 56-62页

作者： Lucky Agarwal Shweta tripathi P.Chakrabarti Department of Electronics & Communication Engineering Motilal Nehru National Institute of Technology Department of Electronics Engineering Indian Institute of Technology(Banaras Hindu University)

A systematic study of the behaviour of Pd/p-ZnO thin film Schottky diode has been *** p-type ZnO thin film with improved stability has been grown on n-type Si by doping ZnO with *** measurement confirmed the p-type nature of Cu-doped ZnO thin *** X-ray diffraction spectra of the deposited film revealed polycrystalline nature with preferred growth orientation of （101） of ZnO *** surface morphological study demonstrated the conformal deposition of a thin film over n-Si *** estimated bandgap of Cu-doped ptype ZnO thin film from ellipsometric measurement turns out to be 3.14 eV at 300 *** measured electrical parameters of the proposed Pd/p-ZnO Schottky diode have also been validated by the results of numerical simulation obtained by using ATLAS^（TM） device simulator.

关键词： p-type ZnO Cu-doped ZnO sol-gel method Schottky diode

Enzymatic and Ultrastructural Studies in a Freshwater Catfish: Impact of Methyl Parathion

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Biomedical and Environmental Sciences 1990年第2期3卷 166-182页

作者： G.tripathi S.P.SHUKLA Department of Zoology Banaras Hindu University Varanasi 221005 India

Exposure to a sublethal concentration of methyl parathion (MEP) reduced the activity of cytoplasmic malate dehydrogenase. mitochondrial malate dehydrogenase, and lactate dehydrogenase by 30 to 49% in the liver and the skeletal muscle of the freshwater catfish, Clarias batraclms, after 7 days. The activities then began to recover and reached the control levels on the 28th day of MEP exposure. A complete recovery occurred on the 7th day when MEP was withdrawn from the medium after an exposure for 1 week. The withdrawal-dependent recovery in the activities was inhibited partially or completely by actinomycin Dandcycloheximide, suggesting de nova synthesis of the enzymes during the recovery period. A conjoint treatment of MEP and triiodolhyronine (T_3) restored the activities to control levels, indicating T_3 protection against the pesticide toxicity. SDS-PAGE of the cytoplasmic fraction of the liver showed some noticeable changes in the protein pattern after an exposure to MEP. Ultrastructural studies on MEP-treated liver cells showed disappearance of the glycogen granules and appearance of numerous smooth endoplasmic reticulum, lysosomal dense bodies, and swollen mitochondria. These changes in the liver are an indication of hepatic toxicity leading toward necrosis.(c) 1990 Academic ***.

关键词： Enzymatic and Ultrastructural Studies in a Freshwater Catfish MEP

Advanced glycation end products:Key mediator and therapeutic target of cardiovascular complications in diabetes

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World Journal of Diabetes 2023年第8期14卷 1146-1162页

作者： Savita Bansal Archana Burman Asok Kumar tripathi Department of Biochemistry Institute of Home SciencesUniversity of DelhiNew Delhi 110016India Department of Biochemistry Institute of Home EconomicsUniversity of DelhiNew Delhi 110016India Department of Biochemistry University College of Medical SciencesUniversity of DelhiNew Delhi 110095India

The incidence of type 2 diabetes mellitus is growing in epidemic proportions and has become one of the most critical public health *** complications associated with diabetes are the leading cause of morbidity and *** cardiovascular diseases that accompany diabetes include angina,myocardial infarction,stroke,peripheral artery disease,and congestive heart *** the various risk factors generated secondary to hyperglycemic situations,advanced glycation end products(AGEs)are one of the important targets for future diagnosis and prevention of *** the last decade,AGEs have drawn a lot of attention due to their involvement in diabetic *** can be derived exogenously and endogenously through various *** are a nonhomogeneous,chemically diverse group of compounds formed nonenzymatically by condensation between carbonyl groups of reducing sugars and free amino groups of protein,lipids,and nucleic *** mediate their pathological effects at the cellular and extracellular levels by multiple *** the cellular level,they activate signaling cascades via the receptor for AGEs and initiate a complex series of intracellular signaling resulting in reactive oxygen species generation,inflammation,cellular proliferation,and fibrosis that may possibly exacerbate the damaging effects on cardiac functions in *** also cause covalent modifications and cross-linking of serum and extracellular matrix proteins;altering their structure,stability,and *** diagnosis of diabetes may prevent its progression to complications and decrease its associated *** the present review,we recapitulate the role of AGEs as a crucial mediator of hyperglycemia-mediated detrimental effects in diabetes-associated ***,this review presents an overview of future perspectives for new therapeutic interventions to ameliorate cardiovascular complications in diabetes.

关键词： Type 2 diabetes mellitus Cardiovascular complications Hyperglycemia Advanced glycation end products Reactive oxygen species Oxidative stress Endothelial cells Receptor of advanced glycation end products Anti-advanced glycation end products strategies