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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, Pr 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

Geochemical Analysis of Albian-Maastrichtian Formations in the Offshore Basin of the Abidjan Margin: rock-Eval Pyrolysis Study

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Open Journal of Geology 2024年第8期14卷 805-822页

作者： n’Guessan Donald Ahoure Blandine Akissi Egoran Guy richard n’Dri Kouadio Zokagon Sylvain Sehi Emmanuelle Laure Oura Zéli Bruno Digbehi UFr of Sciences and Technologies Alassane Ouattara Bouak Laboratory of Plant Biology and Earth Sciences Bouak Cte dIvoire UFr Marine Sciences San Pedro University San Pedro Cte dIvoire PETrOCI Geochimistry Department at the Center for Analysis and Research Abidjan Cte dIvoire UFr/STrM Felix Houphout Boigny University of Abidjan Abidjan Cte dIvoire

The Albian-Maastrichtian interval of the Ivorian sedimentary basin has been the subject of numerous sedimentological, biostratigraphic, and geophysical studies. However, its geochemical characteristics remain relatively unexplored. This study aims to determine the oil potential and the nature of the organic matter it contains. It focuses on the geochemical analysis (physicochemical method) of two oil wells located in the offshore sedimentary basin of Côte d’Ivoire, specifically in the Abidjan margin. A total of 154 cuttings samples from wells TMH-1X and TMH-2X were analyzed to determine their oil potential and the nature of the organic matter (om) they contain. The analyses were performed using rock-Eval pyrolysis, a method that characterizes the amount of hydrocarbons generated by the organic matter present in the rocks. The key parameters measured include Total Organic Carbon (TOC), Hydrogen Index (HI), oil potential (S2), and maximum pyrolysis temperature (Tmax). These parameters are used to assess the amount of organic matter, its thermal maturity, and its potential to generate hydrocarbons in the studied wells. The results show significant variations between different stratigraphic levels. In well TMH-1X, the Cenomanian and Campanian intervals stand out with very good quantities of organic matter (om) with good oil potential, although often immature. In contrast, other stages such as the Albian and Turonian contain organic matter in moderate to low quantities, often immature and of continental type, which limits their capacity to generate hydrocarbons. In well TMH-2X, a similar trend is observed. Despite an abundance of organic matter, the oil potential remains low in most of the studied stages. The organic matter is primarily of type III (continental origin) and thermally immature, indicating a low potential for hydrocarbon generation. The study reveals that, although some intervals exhibit high-quality organic matter, the majority of the samples show insuffic

关键词： Geochemistry rock-Eval Pyrolysis Upper Senonian Petroleum Potential Côte d’Ivoire

Ultra-Low Threshold Optical Bistability and Multi-Stability in Dielecrtric Slab Doped with Semiconductor Quantum Well

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Communications in Theoretical Physics 2016年第7期65卷 129-132页

作者： r.nasehi Young researchers and Elite Club Central Tehran Branch Islamic Azad University

A scheme for switching of the optical bistability(OB) and multi-stability(om) in a dielectric slab doped with a three-level ladder-configuration n-doped semiconductor quantum well is simulated. It is shown that the bistable behavior of the system in dielectric slab can be controlled via amplitude or relative phase of applied fields. This optical system may provide some new possibilities for test the switching process.

关键词： optical bistability quantum well dielectric slab

Benzimidazole derivatives: search for GI-friendly anti-inflammatory analgesic agents

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Acta Pharmaceutica Sinica B 2015年第4期5卷 337-342页

作者： Monika Gaba Punam Gaba Deepika Uppal neelima Dhingra Malkeet Singh Bahia om Silakari Chander Mohan Department of Pharmaceutical Sciences ASBASJSM College of Pharmacy research Scholar Punjab Technical University University Institute of Pharmaceutical Sciences Panjab University Department of Pharmaceutical Sciences and Drug research Punjabi University rayat-Bahra Institute of Pharmacy Hoshiarpur Affiliated to Punjab Technical University

non-steroidal anti-inflammatory drugs(nSAIDs) have been successfully used for the alleviation of pain and inflammation in the past and continue to be used daily by millions of patients worldwide. However, gastrointestinal(GI) toxicity associated with nSAIDs is an important medical and socioeconomic problem. Local generation of various reactive oxygen species plays a significant role in the formation of gastric ulceration associated with nSAIDs therapy. Co-medication of antioxidants along with nSAIDs has been found to be beneficial in the prevention of GI injury. This paper describes the synthesis and biological evaluation of n-1-(phenylsulfonyl)-2-methylamino-substituted-1H-benzimidazole derivatives as anti-inflammatory analgesic agents with lower GI toxicity. Studies in vitro and in vivo demonstrated that the antioxidant activity of the test compounds decreased GI toxicity.

关键词： Benzimidazole Analgesic Gastrointestinal toxicity Antioxidant activity

Ecdysis triggering hormone peptide in the African malaria mosquito Anopheles gambiae:The peptide structure for receptor activation

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Insect Science 2022年第5期29卷 1309-1317页

作者： Hawa Dembele Moritz Mating rupinder Singh Soheila Fatehi Alvaro I.Herrera Yoonseong Park om Prakash Department of Biochemistry and Molecular Biophysics Kansas State UniversityManhattanKansas66506 Department of Entomology Kansas State UniversityManhattanKansas66506 Department of Chemistry&Biochemistry Auburn UniversityAuburnAlabamaUSA

Infections by mosquito-borne diseases represent one of the leading causes of death in third world *** rapid progression of resistance to conventional insecticide causes a significant threat to the highly efficient preventive methods currently in *** neuropeptidergic system offers potential targets to control the insect *** essential roles of the neuropeptide ecdysis triggering hormone(ETH)in insect development and reproduction led us to attempt understanding of the fundamentals of the biochemical interaction between ETH and its receptor in the African malaria mosquito Anopheles *** of two ETH peptides of the African malaria mosquito(AgETH1),a small peptide hormone with 17 amino acid residues(SESPGFFIKLSKSVPrI-nH2),was studied to elucidate its molecular structure.n-termini deletions and mutations of conserved amino acids in the ligand revealed the critical residues for the receptor *** solution structure of AgETH1 using 2D 1H-1H nuclear magnetic resonance(nMr)spectroscopy and nuclear overhauser effect(nOE)derived constraints revealed a short alpha helix between residues 3S and *** nMr solution structure of AgETH1 will be of significant assistance for designing a new class of insecticidal compounds that acts on the AgETH receptor aiming for in silico docking studies.

关键词： Anopheles gambiae ecdysis triggering hormone G protein-coupled receptor insect malaria neuropeptide nMr spectroscopy

Studies on metals and pesticide content in some Ayurvedic formulations containing Bacopa monnieri L.

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Journal of Integrative Medicine 2016年第1期14卷 44-50页

作者： Amrita Mishra Arun K.Mishra om Prakash Tiwari Shivesh Jha Central Facility of Instrumentation School of Pharmaceutical SciencesIFTM University Department of Pharmaceutical Sciences Birla Institute of Technology

OBJECTIVE： Ayurvedic formulations are preferred over other formulations as well as commercialized on broad level to treat various ailments. The World Health Organization has established certain guidelines for quality control of heavy metals and pesticide residues. Bacopa monnieri, a popular herb with immunomodulator and memory-enhancing properties is the chief constituent of several Ayurvedic formulations, which include Brahmi Vati （BV）, Brahmi Ghrita （BG） and Saraswat Churna （SC）, etc. In view of the World Health Organization guidelines, two products of each formulation from six different manufacturers were purchased from Ayurvedic Pharmacy, Bulanala-Varanasi, India for testing heavy metal and pesticide residue. METHODS： In the present study, all the formulations--BY, BG and SC--were selected for estimation of four heavy metals namely lead （Pb）, cadmium （Cd）, chromium （Cr） and nickel （ni） by a plasma emission spectrophotometer. Organochlorine pesticidal residues were estimated for dichlorodiphenyl trichloroethane, isom.rs of hexachlorocyclohexane （HCH） and a-endosulfan, etc. in total 12 samples of test formulations containing Bacopa monnieri L. using gas chromatography technique. rESULTS： Out of 12 samples, Pb, Cd, Cr and ni were present in all samples but below the permissible limit. Although atrazine, aldrin, dialdrin were in below detection limit, but other pesticides were detected in some samples as oxamyl, hexachlorocyclohexanes （α-HCH, β-HCH and y-HCH）, dichlorodiphenyl trichloroethane and dichlorodiphenyl dichloroethylene. COnCLUSIOn： The presence of heavy metals in evaluation of heavy metals and pesticide residue the formulations was low to cause toxicity. However n every batch is necessary.

关键词： Ayurvedic formulations heavy metals pesticide residues drug contamination

Study nanostructure of a Biomaterial with Medicine Therapeutic Activity

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Microscopy research 2016年第2期4卷 32-38页

作者： Marilú Chávez-Castillo Martha Lilia Domínguez-Patiño rosa María Melgoza-alem.n Centro de Investigación en Ingeniería y Ciencias Aplicadas Universidad Autónoma del Estado de Morelos Cuernavaca México Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de Morelos Cuernavaca México

In Mexico, the medicinal plants have been for used since ancient times and still continue to use by rural populations to treat conditions such as infectious diseases (skin, gastrointestinal or respiratory), metabolics, inflammatory problems, among others. This work includes a proposal that initiates the study and development of new biomaterials or vehicles with therapeutic application. The nanomolecular interaction of the organic extract of a plant (EOV) Distictis buccinatoria (dc) with different materials inert supports of inorganic type (bentonite, gel) determining their and combined anti-inflammatory activity is studied individually [1] [2]. The importance of the characterization of biomaterials by scanning electron microscopy (SEM) is ability to analyze the structure on the surface of materials (organic, inorganic and biological) in the micro and nanometrics levels in order to correlate it with the sample surface properties such as roughness, interfacial phenomena, etc. With this technique we can also perform the chemical analysis at different levels (micro and nano) for information on the nature and composition of the materials [3] [4]. The biomaterial shows that higher anti-inflammatory activity is to be generated through the combination of EOV-gel, the nanostructure interaction SEM shows integrated particles agglome-rated form and porous due to the presence of EOV and some flat areas indicated the gel preponderance situation generated by the low interaction between materials of organic type and polar type (gel).

关键词： Biomaterials nanomolecular Anti-Inflamatory Vehicles

High-yield synthesis and liquid-exfoliation of two- dimensional belt-like hafnium disulphide

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nano research 2018年第1期11卷 343-353页

作者： Harneet Kaur Sandeep Yadav Avanish K. Srivastava nidhi Singh Shyama rath Jorg J. Schneider om P. Sinha ritu Srivastava national Physical Laboratory Council of Scientific and Industrial Research Dr. K. S. Krishnan Road New Delhi I I O012 India Academy of Scientific and Innovative research NPL New Delhi 110012 India Technische Universitat Darmstadt Eduard-ZintMnstitut f~r Anorganische und Physikalische Chemie 12 105 117 Alarich-Weiss-Str 12 64287 Darmstadt Germany DepartmentofPhysics andAstrophysics University of Delhi Delhi 110007 India Amity Institute of nanotechnology Amity University UP Sector 125 Noida Uttar Pradesh 201313 India

Producing environmentally stable monolayers and few-layers of hafnium disulphide （HfS2） with a high yield to reveal its unlocked electronic and optoelectronic applications is still a challenge. HfS2 is a layered two-dimensional material of group-IV transition metal dichalcogenides. For the first time, we demonstrate a simple and cost-effective method to grow layered belt-like nanocrystals of HfS2 with a notably large interlayer spacing followed by their chemical exfoliation. Various microscopic and spectroscopic techniques confirm that these as-grown crystals exfoliate into single or multiple layers in a few minutes using solvent assisted ultrasonification method in n-cyclohexyl-2- pyrrolidone. The exfoliated nanosheets of HfS2 exhibit an indirect bandgap of 1.3 eV with high stability against surface degradation. Furthermore, we demonstrate that these nanosheets hold potential for electronic applications by fabricating a field-effect transistor based on few-layered HfS2, exhibiting a field-effect mobility of 0.95 cm2/（V.s） with a high on/off current modulation ratio of 10,000 in ambient conditions. The method is scalable and has a potential significance for both academic and industrial purposes.

关键词： two-dimensionalmaterials hafnium disulphide nano-crystals liquid-phase exfoliation environment-stabili~ field-effect transistor

Pure and Mixed Plantations of <i>Eucalyptus camaldulensis</i>and <i>Cupressus lusitanica</i>: Their Growth Interactions and Effect on Diversity and Density of Undergrowth Woody Plants in relation to Light

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Open Journal of Forestry 2015年第4期5卷 375-386页

作者： Shiferaw alem Jindrich Pavlis Josef Urban Jiri Kucera Department of Forest Botany Dendrology and Geobiocenology Mendel University in Brno Zemedelska 3/613 00 Brno Czech Republic EMS Brno Turisticka 5 621 00 Brno Czech Republic

Published results on the growth interactions of non-nitrogen fixing mixed plantations species, and their impact on the regeneration of woody plants are scant. This paper addresses the growth interactions of pure and mixed plantations of Eucalyptus camaldulensis and Cupressus lusitanica and their impact on the regeneration of woody plants in relation with light. Data on the regenerated woody plants, individual characteristics of the plantation species and light reaching under the canopies were collected using sample plots (n = 4) with a size of 20 m × 20 m for each plantation type. The result showed that, E. camaldulensis was suppressing the growth of C. lusitanica while its growth was favored when it was mixed with C. lusitanica (p re were no significant differences between the pure and mixed plantations in their diversity and density of undergrowth woody plants (p > 0.05). Density of plantation trees were found not having a significant relationship with diversity of species (p = 0.801). There was a significant but not direct relationship between light reached in the understory of the canopies and diversity of species in the plantations (p = 0.027). Overall, the result indicated that both the pure and the mixed plantations were favoring the recruitment of woody plants.

关键词： Diversity Growth Light Mixed Plantation Pure Plantation Woody Plants