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Status and determinants of other gainful activities by farmers in mountainous rural regions of Gilgit-Baltistan,Pakistan

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Journal of Mountain Science 2021年第10期18卷 2520-2539页

作者： SHAHZAD Muhammad Abid AHMED Vaqar FISCHER christian Faculty of Science and Technology Free University of Bozen-BolzanoBolzano 39100Italy Sustainable Development Policy Institute Islamabad 44000Pakistan

Non-farm income sources are important for livelihood sustenance,especially in the mountainous regions of developing *** implement effective policies to improve economic development,policymakers need insights at the grassroots ***,there is a lack of empirical evidence in the context of *** study examines the current situation and the factors influencing the decision by farmers to engage in other gainful activities(OGAs)such as farm diversification and off-farm work in the northern mountainous regions of *** study is based on quantitative survey data obtained from 459 farm managers and qualitative data from 24 key informants from five different districts in *** a logistic regression model,a statistical analysis is conducted on farmer and farm characteristics to investigate the probability of farm managers to engage in *** survey results show that around 71%of farm managers are engaged in OGAs(with 24%in farm diversification,61%in offfarm work and 15%in both).The share of female farm managers is 51%in farm diversification while male farm managers dominate off-farm activities(69%).The most prevalent types of farm diversification are the processing of farm products and tourism-related farm work,while the main off-farm activities are setting up grocery stores outside the farm,having salaried jobs or engaging in other non-agricultural *** are significant differences between farmers with and without OGAs particularly regarding farmer characteristics,agricultural income and some other *** logit model results show that farmer characteristics mainly determine off-farm work activities while farm(and other)characteristics mostly explain farm *** findings suggest that OGAs primarily exist as livelihood *** diversification is linked with the long-term sustenance of agricultural activities while off-farm work is predominantly driven by economic *** types of OGAs re

关键词： Other gainful activities Off-farm work Farm diversification Gilgit-Baltistan Pakistan

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COVID-19:Insights into long-term manifestations and lockdown impacts

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Journal of Sport and Health Science 2023年第4期12卷 438-463页

作者： Erika Hilbold christian Bär Thomas Thum Institute of Molecular and Translational Therapeutic Strategies(IMTTS) Hannover Medical SchoolHannover 30625Germany Fraunhofer Cluster of Excellence Immune-Mediated Diseases(CIMD) Hannover 30625Germany Fraunhofer Institute for Toxicology and Experimental Medicine(ITEM) Hannover 30625Germany

Coronaviruses are pathogens thought to primarily affect the respiratory tracts of *** outbreak of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)in 2019 was also marked mainly by its symptoms of respiratory illness,which were named coronavirus disease 2019(COVID-19).Since its initial discovery,many other symptoms have been linked to acute SARS-CoV-2 infections as well as to the long-term outcomes of COVID-19 *** these symptoms are different categories of cardiovascular diseases(CVDs),which continue to be the main cause of death *** World Health Organization estimates that 17.9 million people die from CVDs each year,accounting for~32%of all deaths *** inactivity is one of the most important behavioral risk factors for *** COVID-19 pandemic has affected CVDs as well as the physical activity in different ***,we provide an overview of the current status as well as future challenges and possible solutions.

关键词： Cardiovascular disease COVID-19 Long COVID Physical activity Return to play

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Flow-structure interaction of an inverted flag in a water tunnel

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Science China(Physics,Mechanics & Astronomy) 2019年第12期62卷 57-67页

作者： YaoWei Hu JiangSheng Wang JinJun Wang christian Breitsamter Key Laboratory of Fluid Mechanics(Beihang University) Ministry of EducationBeijing 100191China Lehrstuhl fur Aerodynamik und Stromungsmechanik Technische Universitat MiinchenGarching 85748Germany

Herein, the dynamics and flow fields of an inverted flag are studied using hydrogen bubble flow visualization and particle image velocimetry technologies at different height-to-length ratios and flow velocities in a water tunnel. Results show that the heightto-length ratio of the inverted flag at which the critical flow velocity remains nearly constant is approximately 1.4. Moreover, a nonperiodic flapping phenomenon is observed under various height-to-length ratios. This phenomenon may be attributed to the existence of multiple equilibrium solutions to the self-excited vibration system, thus engendering chaos in the system comprising an inverted flag and surrounding fluid. Other indications that the system has entered chaos include multiple frequencies, nonoverlapping phase diagram, and positive Lyapunov exponent. Further discussion of the flow fields around the inverted flag reveals that the large-amplitude oscillation is due to the flow separation, while the flapping instability is a static divergence instability. In the large flapping mode, the starting leading-edge vortex(LEV) is wrapped by Kelvin-Helmholtz instabilities,which are arranged at almost uniform spacing along a circular path. In addition, the variation in position, circulation, and radius of the starting LEV are discussed in detail.

关键词： inverted flag modes aperiodic flapping LEV

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Chemical composition and formation mechanisms in the cathode-electrolyte interface layer of lithium manganese oxide batteries from reactive force field （ReaxFF） based molecular dynamics

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Frontiers in Energy 2017年第3期11卷 365-373页

作者： Sahithya REDDIVARI christian LASTOSKIE Ruofei WU Junliang ZHANG Perimeter College Georgia State University Clarkston GA 30021 USA Department of Civil and Environmental Engineering University of Michigan Ann Arbor MI 48109-2125 USA Institute of Fuel Cells MOE Key Laboratory of Power & Machinery Engineering Shanghai Jiao Tong University Shanghai 200240 China

Lithium manganese oxide （LiMn2O4） is a principal cathode material for high power and high energy density electrochemical storage on account of its low cost, non-toxicity, and ease of preparation relative to other cathode materials. However, there are well-documented problems with capacity fade of lithium ion batteries containing LiMn2O4. Experimental observations indicate that the manganese content of the electrolyte increases as an electrochemical cell containing LiMn2O4 ages, suggesting that active material loss by dissolution of divalent manganese from the LiMn2O4 surface is the primary reason for reduced cell life in LiMn2O4 batteries. To improve the retention of manganese in the active material, it is key to understand the reactions that occur at the cathode surface. Although a thin layer of electrolyte decomposition products is known to form at the cathode surface, the speciation and reaction mechanisms of Mn^2＋ in this interface layer are not yet well understood. To bridge this knowledge gap, reactive force field （ReaxFF） based molecular dynamics was applied to investigate the reactions occurring at the LiMn2O4 cathode surface and the mechanisms that lead to manganese dissolution. The ReaxFFMD simulations reveal that the cathode-electrolyte interface layer is composed of oxida- tion products of electrolyte solvent molecules including aldehydes, esters, alcohols, polycarbonates, and organic radicals. The oxidation reaction pathways for the electro- lyre solvent molecules involve the formation of surface hydroxyl species that react with exposed manganese atoms on the cathode surface. The presence of hydrogen fluoride （HF） induces formation of inorganic metal fluorides and surface hydroxyl species. Reaction products predicted by ReaxFF-based MD are in agreement with experimentally identified cathode-electrolyte interface compounds. An overall cathode-electrolyte interface reaction scheme is proposed based on the molecular simulation results.

关键词： lithium manganese oxide batteries reactiveforce field (ReaxFF) cathode-electrolyte interface layer,molecular dynamics

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Nature-based recreation for the elderly in urban areas:assessing opportunities and demand as planning support

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Ecological Processes 2022年第1期11卷 587-603页

作者： Chen Wen christian Albert Christina von Haaren School of Architecture and Urban Planning Huazhong University of Science and TechnologyLuoyu Road430074 WuhanChina Institute of Environmental Planning Leibniz University HannoverHannoverGermany Institute of Geography Ruhr University BochumBochumGermany

Background:With elderly people comprising a growing share of the population,landscape planners need to consider their specific requirements to enhance the opportunities for them to engage in nature-based recreation(NBR).However,few studies have spatially assessed the recreation potential,demand,and opportunities for elderly people in ***,this paper aimed to spatially model and investigate the NBR opportunities for and demand of elderly people in urban areas.A spatial framework based on the ESTIMAP recreation model was developed,considering special factors to better reflect elderly people’s preferences regarding NBR at the city *** particular,NBR opportunities were assessed considering landscape aesthetics,various types of facilities,and *** street network was used to understand elderly people’s walking behaviours regarding green spaces and related ***:A case study in Hannover,Germany,demonstrated the applicability of the proposed *** results illustrate the spatial heterogeneity of recreation options for the *** parts of Hannover’s green spaces offer high recreation opportunities for elderly *** of the existing green spaces lack diverse landscape compo-nents and sufficient supply of facilities,resulting in a compromise to aesthetics and recreational ***:The proposed method contributes to research on spatial planning and environmental justice by incorporating vulnerable groups’preferences and needs in spatially assessing *** planning implications highlight pocket gardens and greenways connecting communities and parks as development opportunities in the city.

关键词： Sustainability Nature-based recreation Population aging Landscape architecture GIS mapping Urban design

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Sedimentation acceleration of remanent iron oxide by magnetic flocculation

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China Particuology 2007年第1期5卷 145-150页

作者： Mathias Stolarski christian Eichholz Benjamin Fuchs Hermann Nirschl Institute of Mechanical Process Engineering and Mechanics (MVM) University of Karlsruhe 76131 Karlsruhe Germany DuPont Experimental Station Building E304 Wilmington DE 19880 USA

Sedimentation based processes are widely used in industry to separate particles from a liquid phase. Since the advent of the ＂Nanoworld＂ the demand for effective separation technologies has rapidly risen, calling for the development of new separation concepts, one of which lies in hybrid separation using the superposition of a magnetic field for magnetic particles. Possible product portfolio of such separation consists of pigment production, nanomagnetics production for electronics and bio separation, A promising step in that direction is magnetic field enhanced cake filtration, which has by now progressed from batch to continuous ooeration. In sedimentation processes in a mass force field the settling behaviour of particles strongly depends on physico-chemical properties, concentration and size distribution of the particles. By adjusting the pH, the interparticle forces, in particular the electrostatic repulsion, can be manipulated. For remanent magnetic particles such as magnetite, pre-treatment in a magnetic field could lead to a change of interparticle interactions. By magnetizing the particles apart from van der Waals attraction and electrostatic repulsion, an additional potential is induced, the magnetic attraction, which could easily dominate the other potentials and result in agglomeration in the primary minimum. By sedimentation analysis, a wide spectrum of parameters like pH, magnetic field strength and concentration have been investigated. The results show a strong increase of sedimentation velocity by magnetic flocculation of the raw suspension. This leads to a rise in throughput due to the acceleration of sedimentation kinetics by imparting a non-chemical interaction to the physico-chemical properties in the feed stream of the separation apparatus.

关键词： Magnetic flocculation Field enhanced separation Cake filtration Magnetic structuring Magnetic separation

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Early dynamics in plant community trait responses to a novel, more extreme hydrological gradient

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Journal of Plant Ecology 2019年第2期12卷 327-335页

作者： Andrea Oddershede Cyrille Violle Annette Baattrup-Pedersen Jens-christian Svenning christian Damgaard Section for Plant and Insect Ecology Department of BioscienceAarhus UniversityVejlsøvej 25DK-8600 SilkeborgDenmark Section for Ecoinformatics&Biodiversity Department of BioscienceAarhus UniversityNy Munkegade 114DK-8000 Aarhus CDenmark CEFE UMR 5175 CNRS-Universitéde Montpellier-UniversitéPaul-Valéry MontpellierEPHE-1919 route de MendeF-34293 MontpellierCEDEX 5France Section for Stream and Wetland Ecology Department of BioscienceAarhus UniversityVejlsøvej 25DK-8600 SilkeborgDenmark

Aims For temperate regions such as Northern Europe,predicted climate change patterns include an increase in winter precipitation causing increased risk of flooding,whereas periods of droughts will become more frequent in *** aim of this study is to explore vari-ations in plant functional trait distributions along a hydrological gradient spanning from recurrent drought events to recurrent flood-ing-mimicking future precipitation *** The experiment was conducted in a controlled grassland experi-ment over a period of 3 years.A novel and more extreme hydro-logical regime was achieved by manipulating the flow of a nearby stream thereby creating a continuous hydrological gradient from flooding during winter to drought during *** commu-nity responses were recorded along this hydrological ***-weighted trait distribution changes along the gradient were described using null *** functional traits were con-sidered:seed mass,leaf dry matter content(LDMC),leaf area,leaf thickness,specific leaf area(SLA)and *** findings Over time,responses in plant functional traits changed at the community *** the study period consistent changes occurred in the mean trait value of several *** in relatively dry plots became dominated by species with water-conserving life strategies,represented by high seed mass and thick *** contrast,disturbance-resistant species(high leaf dry matter content)became dominant in flooded plots,indicating that persistence to flooding was the most important factor control-ling the functional structure in those ***,a high abundance of small-seeded species in flooded plots likely indicates higher frequency of species with higher dispersal ability through *** conclusion,plant traits are useful for predicting responses to climate change,but abrupt and extreme climate event may cause unexpected responses because they have no analog to previously more sta

关键词： functional diversity trait-environment relationship hydrology extreme events flooding

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Clustering of voltage-gated ion channels as an evolutionary trigger of myelin formation

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Neural Regeneration Research 2024年第8期19卷 1631-1632页

作者： Henrike Ohm Simone Rey christian Klambt Institut fur Neuro-und Verhaltensbiologie MunsterGermany

Neurons carry apical dendrites that perceive information and a basal axon that transmits the computed information towards its to *** axon originates at the axon hillock which is followed by the axon initial ***,action potentials are initiated that are based on millisecond long openings of specific voltagegated sodium and potassium channels that are conserved in all parahoxozoa(Placozoa,Cnidaria,Bilateria)(Li et al.,2015).

关键词： initiated carry potassium

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Tribological performance and microstructural evolution ofα-brass alloys as a function of zinc concentration

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Friction 2020年第6期8卷 1117-1136页

作者： Zhilong LIU Philipp MESSER-HANNEMANN Stephan LAUBE christian GREINER Institute for Applied Materials(IAM) Karlsruhe Institute of Technology(KIT)Karlsruhe 76131Germany KIT IAM-CMS MikroTribologie CentrumμTC Karlsruhe 76131Germany

Tailoring a material's properties for low friction and little wear in a strategic fashion is a long-standing goal of materials *** deformation plays a major role when metals are employed in a sliding contact;therefore,the effects of stacking fault energy and mode of dislocation glide need to be ***,we investigated how a decrease in the stacking fault energy affects friction,wear,and the ensuing sub-surface microstructure *** samples with increasing zinc concentrations of 5,15,and 36 wt%were tested in non-lubricated sphere-on-plate contacts with a reciprocating linear tribometer against Si3N4 *** the sliding distance from 0.5(single trace)to 5,000 reciprocating cycles covered different stages in the lifetime of a sliding *** the results among the three alloys revealed a profound effect of the zinc concentration on the tribological ***15 and CuZn36 showed similar friction and wear results,whereas CuZn5 had a roughly 60%higher friction coefficient(COF)than the other two ***15 and CuZn36 had a much smaller wear rate than *** dislocation motion in CuZn5 and CuZn15 allowed for dislocation self-organization into a horizontal line about 150 nm beneath the contact after a single trace of the *** feature was absent in CuZn36 where owing to planar dislocation slip band-like features under a 45°angle to the surface were *** results hold the promise to help guide the future development of alloys tailored for specific tribological applications.

关键词： brass tribology sliding contact microstructure stacking fault energy electron microscopy

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The effect of microclimate on wood decay is indirectly altered by tree species diversity in a litterbag study

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Journal of Plant Ecology 2017年第1期10卷 170-178页

作者： David Eichenberg Katherina Pietsch christian Meister Wenyong Ding Mingjian Yu christian Wirth Institut für Spezielle Botanik und Funktionelle Biodiversität University of LeipzigJohannisallee 21-23Leipzig 04103Germany College of Life Sciences Zhejiang University866 Yuhangtang RoadHangzhou 310058China German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5eLeipzig 04103Germany

Aims We studied the influence of tree species diversity on the dynamics of coarse wood decomposition in developing forest communities in a natural,topographically heterogeneous *** the litter bag technique,we investigated how and to which extent canopy tree species richness or the exclusion of mesoinvertebrates and macroinvertebrates affected wood decomposition in the light of natural variations in the *** compared the relative importance of the two aspects(experimental treatment versus microclimate)on wood decay rates using Schima superba as a standard *** Coarse woody debris(CWD)was deposited in litter bags with two different mesh sizes in a total of 134 plots along a gradient of canopy tree species richness(0-24 species).Wood decomposition was assessed at two consecutive time points,one and three years after deposition in the *** climatic conditions were assessed throughout the duration of the *** conditions were assessed both,directly in the field as well as indirectly via correlations with local *** used analysis of variance based approaches to assess the relative importance of the treatments(community tree species richness and macro invertebrate exclusion)and microclimatic conditions on wood *** Findings No direct influence of tree species richness on wood decay could be ***,the exclusion of macroinvertebrates significantly decreased wood decomposition *** addition,microclimatic conditions accounted for a substantial proportion of explained variance in the observed ***,wood decomposition was negatively affected by low mean temperatures and high variations in local humidity and ***,tree species richness as well as the respective species composition affected the presence of termites within forest ***,in turn,significantly increased the decay of *** strength of both,experimental treatment and microclimate increased with o

关键词： wood decomposition microclimate litter bag tree species diversity community composition

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