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Birds of the Kangchenjunga Landscape,the Eastern Himalaya:status,threats and implications for conservation

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Avian Research 2018年第4期9卷 381-393页

作者： Pratikshya Kandel Ishana Thapa Nakul chettri Rebecca Pradhan Eklabya Sharma International Centre for Integrated Mountain Development GPO Box 3226KathmanduNepal Bird Conservation Nepal KathmanduNepal Royal Society for Protection of Nature(RSPN) ThimphuBhutan

Birds are reliable and widely used indicators for conservation planning and monitoring. We reviewed birds of the Kangchenjunga Landscape, a transboundary complex shared by Bhutan, India and Nepal in the Eastern Himalaya. Using 119 literature, we analyzed the bird survey efforts in the landscape, their taxonomic representation, global threat status, distribution patterns, and habitat preferences. We also discussed the potential threats and conservation challenges and documented current conservation efforts and government policies. Most of the bird surveys are carried out in India followed by Nepal and Bhutan. A total of 618 bird species belonging to 19 orders and 77 families are recorded. Passeriformes is the dominant order that constitutes 62% of the total records listed from the landscape. Among the families, Muscicapidae is the most common and diversely represented family. There are 41 species of birds that are categorized as threatened under IUCN Red List. Of the total birds occurring in the landscape, the highest number of bird species(95%) was documented from India, followed by Nepal(55%) and Bhutan(34%). Of them, 24% of the species were found to occur in the tropical zone. Forested habitat is widely used by 63% of the total species followed by wetlands(16%). Despite promising policies and legal provisions, the landscape faces numerous challenges including habitat loss and fragmentation, hunting and trapping, unsustainable extraction of natural resources, invasive alien species, unregulated tourism and global climate change. We suggest protection and management of birds through strengthening Important Bird and Biodiversity Areas, reduction in forest encroachment and habitat destruction, conservation awareness programmes and comprehensive bird surveys with long term monitoring to assess the impact of environmental change as some of the approaches to conserve the rich avifaunal diversity of the landscape.

关键词： Avifauna Transboundary landscape Nepal India Bhutan Biodiversity Conservation

Serrated flow accompanied with dynamic type transition of the Portevin-Le Chatelier effect in austenitic stainless steel

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Journal of Materials Science & Technology 2023年第2期133卷 154-164页

作者： Seung-Yong Lee Sita chettri Ritupan Sarmah Chikako Takushima Jun-ichi Hamada Nobuo Nakada Department of Materials Science and Engineering Tokyo Institute of Technology4259 Nagatsuta-choMidori-kuYokohama-shiKanagawa-ken 226-8503Japan Department of Physics Tezpur UniversityNappamTezpur 784028India Research and Development Center Nippon Steel Stainless Steel CorporationHikari 743-8550Japan

In order to further understand high-temperature deformation behavior and its-related mechanical prop-erties,the Portevin-Le Chatelier(PLC)effect in an Fe-19Cr-13Ni-0.2C austenitic stainless steel was in-vestigated using high-temperature digital image correlation(DIC)*** the tensile testing at temperatures from 473 to 623 K,different types of serrated flow appeared even at a constant applied strain rate,and the type transition took place dynamically in a certain order with deformation *** analysis revealed that the dynamic type transition of the serrated flow obeys the PLC band propagation behavior,and that the transition of the PLC band propagation behavior could be attributed to the PLC band nucleation *** modeling also proved that the nucleation manner of PLC band nu-cleation is determined by the spatial-temporal coupling effect.

关键词： Dynamic strain aging(DSA) Austenitic stainless steel(γ-STS) Portevin-Le Chatelier(PLC)effect Digital image correlation(DIC) Local strain distribution

Impact of land cover change on a mountain ecosystem and its services:case study from the Phobjikha valley,Bhutan

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Ecosystem Health and Sustainability 2017年第9期3卷 16-28页

作者： Sunita Chaudhary Dago Tshering Tshering Phuntsho Kabir Uddin Bandana Shakya Nakul chettri Ecosystem Services International Centre for Integrated Mountain Development(ICIMOD)KathmanduNepal Research Program Royal Society for Protection of Nature(RSPN)ThimphuBhutan Department of Geography and Planning Macquarie UniversitySydneyAustralia

Introduction:Mountains occupy 24%of the global land surface and are home to 12%of the world’s population;they host the world’s principal biomes and supply a diverse array of ecosystem *** they are also highly sensitive to both natural and human induced changes,which can affect service provision meant for one third of *** research on impacts of land cover change from mountains at the local scale are limited,especially in developing countries,which poses a barrier to informed planning for sustainable *** being in the forefront as contributor towards global conservation goals,a case study following a systematic research framework considering quantitative,qualitative and geospatial tools was ***:Respondents identified and ranked 24 ecosystem services,among which the provisioning services were the most important,followed by cultural,regulating,and supporting *** was the most important land cover type for services,followed by marsh,scrub,water bodies,and *** area of forest declined by 2%and marsh by 7%over the 32-year period,suggesting a potential decrease in ecosystem services,which was also observed by the local ***:It was observed that 80%of the local people are still directly dependent on the diverse ecosystems for *** subtle,the decrease in land cover has implications for livelihoods of the people and the rich biodiversity of the *** communities for local development needs guidance for identifying trade-offs in land cover types in sustainable *** integrated and holistic approach focusing on both conservation and community development should be used to manage and develop the valley and the region ***:We recommend diversifying the limited livelihood strategies(potato farming and livestock grazing)to reduce the potential vulnerability of the local community and reduce the pressure on forest and *** land use planning

关键词： forest valley Impact

Nonlinear Coupling of Kinetic Alfvén Waves and Ion Acoustic Waves in the Inner Heliosphere

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Research in Astronomy and Astrophysics 2024年第10期24卷 141-158页

作者： Mani K.chettri Vivek Shrivastav Rupak Mukherjee Nidhi Gaur R.P.Sharma Hemam D.Singh Department of Physics Sikkim UniversityGangtokSikkimIndia DAV Public School Sector 14GurugramHaryanaIndia Plasma Simulation Laboratory Department of Energy Science and EngineeringIndian Institute of Technology DelhiDelhiIndia

We study the nonlinear coupling of kinetic Alfvén waves with ion acoustic waves applicable to the Earth’s radiation belt and near-Sun streamer belt solar wind using dynamical equations in the form of modified Zakharov *** simulations show the formation of magnetic field filamentary structures associated with density humps and dips which become turbulent at later times,redistributing the energy to higher *** magnetic power spectra exhibit an inertial range Kolmogorov-like spectral index value of-5/3 for k_(⊥)ρ_(i)<1 followed by a steeper dissipation range spectra with indices~-3 for the radiation belt case and~-4 for the nearSun streamer belt solar wind case,here k_(⊥)andρ_(i)represent the wavevector component perpendicular to the background magnetic field and the ion thermal gyroradius,*** quasilinear theory in terms of the Fokker-Planck equation in the region of wavenumber turbulent spectra,we find the particle distribution function flattening in the superthermal tail population which is the signature of particle energization and plasma heating.

关键词： Sun:chromosphere Sun:corona Sun:heliosphere

Plant diversity of the Kangchenjunga Landscape, Eastern Himalayas

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Plant Diversity 2019年第3期41卷 153-165页

作者： Pratikshya Kandel Nakul chettri Ram P.Chaudhary Hemant Kumar Badola Kailash S.Gaira Sonam Wangchuk Namgay Bidha Yadav Uprety Eklabya Sharma International Centre for Integrated Mountain Development Kathmandu Nepal Research Centre for Applied Science and Technology (RECAST) Kathmandu Nepal G B Pant National Institute of Himalayan Environment and Sustainable Development (GBPNIHESD) Sikkim India Nature Conservation Division Department of Forest and Park Services Thimphu Bhutan

The Kangchenjunga Landscape (KL) in the Eastern Himalayas is a transboundary complex shared by Bhutan, India, and Nepal. It forms a part of the ‘Himalayan Biodiversity Hotspot’ and is one of the biologically richest landscapes in the Eastern Himalayas. In this paper, we use secondary information to review and consolidate the knowledge on the flora of the KL. We reviewed 215 journal articles, analysed the history of publications on the flora of the KL, their publication pattern in terms of temporal and spatial distribution and key research areas. Our review shows that the landscape has a long history of botanical research that dates back to the 1840s and progressed remarkably after the 1980s. Most of the studies have been carried out in India, followed by Nepal and Bhutan. The majority of these have been vegetation surveys, followed by research on ethnobotanical aspects and Non-Timber Forest Products (NTFPs). This paper describes the forest types and characteristic species of the KL and details the species richness, diversity and dominant families of seed plants. A total of 5198 species of seed plants belonging to 1548 genera and 216 families have been recorded from the landscape, including 3860 dicots, 1315 monocots and 23 gymnosperms. Among families, Orchidaceae is the most diversely represented family in terms of species richness. This paper also draws attention to the threatened and endemic flora of the KL, including 44 species that are threatened at national and global level and 182 species that are endemic. Finally, the paper reviews the major challenges facing the KL, the conservation efforts and practices that are currently in place and recommends systematic and comprehensive floral surveys, particularly long-term data collection and monitoring and transboundary collaboration, to address the existing knowledge gaps on floral diversity of the KL.

关键词： Floral diversity Transboundary landscape Nepal India Bhutan Biodiversity

A New Furunculosis Challenge Method for Evaluation of Vaccine Efficacy in Rainbow Trout

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Open Journal of Immunology 2016年第4期6卷 136-147页

作者： Moonika H. Marana Jiwan K. chettri Jakob Skov Inger Dalsgaard Per W. Kania Kurt Buchmann Department of Veterinary Disease Biology Faculty of Health and Medical Sciences University of Copenhagen Frederiksberg Denmark National Veterinary Institute Technical University of Denmark Frederiksberg Denmark

Experimental infection of fish for vaccine efficacy studies is associated with several limitations. Administration of live bacteria with the purpose of causing disease in fish can be performed by co-habitation, immersion or injection. We have developed a new Aeromonas salmonicida challenge method for rainbow trout and have applied it for evaluation of furunculosis vaccine efficacy. The method reveals development of systemic immunity in fish as live bacteria are introduced in the tail fin epidermis distant from the vaccine injection site (peritoneal cavity). This method seeks to mimic natural infection in fish farms where tail biting and therefore bacterial exposure to tail fin ulcers is widespread. By use of a multi-needle device ten epidermal perforations were introduced in the dorsal part of the tail fin of anaesthetized rainbow trout (vaccinated or naive). Subsequently 100 μL (3.4 × 108 colony-forming units (CFU) mL-1) of a 48 hour culture of Aeromonas salmonicida subsp. salmonicida strain 090710-1/23 was placed at the perforation site for 60 sec whereafter fish were allowed to regain consciousness in clean freshwater. Immunohistochemistry and scanning electron microscopy illustrated the spread of bacteria from the injection site. Classical furunculosis symptoms associated with a high morbidity rate were observed in control fish whereas vaccinated fish exhibited a significantly higher survival.

关键词： Aeromonas salmonicida Challenge Method Furunculosis Immunization Salmonids