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Selective and taxon-dependent effects of semi-feral cattle grazing on tree regeneration in an old-growth Mediterranean mountain forest

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Forest Ecosystems 2020年第1期7卷 128-140页

作者： Xavier fortuny Christopher Carcaillet Sandrine Chauchard Ecole Pratique des Hautes Etudes(EPHE) PSL University75014 ParisFrance Laboratoire d’ cologie des Hydrosystèmes Naturels et Anthropisés(UMR5023 CNRS UniversitéLyon 1ENTPE)69622 VilleurbanneFrance Universitéde Lorraine AgroParisTechINRAEUMR Silva54000 NancyFrance

Background:In Mediterranean mountain socio-ecosystems,both grazing by livestock and the dry season may influence tree ***,the relative contributions of these drivers are poorly known,even though present and future canopy composition might result from past and present variations in climate and herbivore *** study aims to test how semi-feral cattle presence and season affect tree ***:The study was conducted using permanent plots inside and outside a cattle exclosure in an old-growth Mediterranean *** and seedlings were counted five times per year(winter,early spring,middle spring,summer,fall)and monitored over 7 ***:Semi-feral cattle exclusion increased Acer,Fagus,Ilex,Pinus,Prunus and Quercus sapling densities and increased Acer,Fraxinus,Ilex,Quercus and Sorbus seedling ***,the dry season did not exert any noticeable effects on the sapling or seedling densities of any of the studied ***:Semi-feral cattle presence may limit tree regeneration through taxon-dependent effects,which suggests that the current decrease in grazing livestock across the Mediterranean basin will modify recruitment processes and,likely,future forest ***:Semi-feral cattle presence acts as a selective driver of tree community composition.

关键词： Cattle Climate Experiment Herbivory Forest pastoralism

Closed 3-stop Center and Periphery in Graphs

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Acta Mathematica Sinica,English Series 2012年第3期28卷 439-452页

作者： Linda EROH Ralucca gera Steven J. WINTERS department of Mathematics University of Wisconsin Oshkosh department of Applied Mathematics Naval Postgraduate School

A delivery person must leave the central location of the business, deliver packages at a number of addresses, and then return. Naturally, he/she wishes to reduce costs by finding the most efficient route. This motivates the following： Given a set of k distinct vertices S = {x1, x2,..., xk } in a simple graph G, the closed k-stop-distance of set S is defined to be

关键词： Central appendage number peripheral appendage number Steiner distance

Biochemical dissection of STAT3 signaling in amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第11期20卷 3229-3230页

作者： Savina Apolloni Nadia d’Ambrosi department of Biology University of Rome Tor VergataRomeItaly

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease characterized by the loss of upper and lower motor neurons,clinically marked by muscle atrophy and *** the clinical course is highly variable,the average time from the onset of symptoms to the need for respiratory support or death is 3-5 *** is the most prevalent motor neuron disease in adults,occurring at a rate of 2 per 100,000 individuals and affecting 5.4 per 100,000 individuals overall.

关键词： STAT3 dissection sclerosis

A Systems Approach for Analyzing Vegetative and Soil degradation in Arnigad Micro-watershed of Indian Himalayan Region

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Journal of Mountain Science 2010年第4期7卷 315-326页

作者： Mohit gera Prem L.Sankhayan Ole Hofstad Govt. of J&K VanbhavanBelow GumatJammu-180001(J&K) India department of Ecology and Natural Resource Management Norwegian University of Life Sciences(UMB)P.O.Box 5003N-1432 sNorway

This study analyzes the vegetative and soil degradation,measured as biomass and soil loss,for Arnigad micro-watershed located in Indian Himalayan state of Uttarakhand,in systems framework by using dynamic linear programming bio-economic *** focus is at investigating the effects of alternate policy regimes,i.e.,introduction of improved energy sources for cooking along with substitution of existing local livestock breeds with improved breed,reduction in human population growth and introduction of high yielding varieties of main crops including paddy,maize and *** model horizon extended over a period of 25 years,i.e.,from 2006 to *** was found that the model scenario incorporating increased use of improved energy sources along with substitution of local cows by improved cows could be the most effective policy option in reducing vegetative and soil *** vegetative biomass density declined to 19.76% compared to 35.24% in the BASE scenario and soil erosion loss was also lowered by 29.13%.Also,the reduction of population growth rate to half of the BASE scenario led to minor improvements in *** of high yielding varieties of main crops slightly increased vegetative degradation but reduced soil loss(8.35%) with respect to the BASE *** a phenomenon could be explained in terms of changed crop mix resulting in reduced amount of crop by-products requiring increased lopping of tree branches for animal *** policy option of the increased use of improved energy sources along with substitution of improved breed of cows resulted in 9.58% higher *** of high yielding varieties of crops led to 1.92% increase in income,but the income decreased by 1.25 % when population growth was reduced to *** usefulness of the model lies in analyzing the systems behavior in its entirety where the results can predict the possible direction of change as a result of manipulation in alternate economic regimes.

关键词： Bio-economic model dynamic linearprogramming Improved energy sources Vegetativeand soil degradation Soil erosion Indian Himalayanregion

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

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Neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： danko Jeremic Lydia Jiménez-díaz Juan d.Navarro-López NeuroPhysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s disease(Ad)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in Ad,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

Remaking a connection:molecular players involved in post-injury synapse formation

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Neural Regeneration Research 2025年第6期20卷 1719-1720页

作者： diogo Tomé Ramiro d.Almeida iBiMEd-Institute of Biomedicine Department of Medical SciencesUniversity of AveiroAveiroPortugal CNC-Center for Neuroscience and Cell Biology University of CoimbraCoimbraPortugal

Functional recovery from central nervous system(CNS)trauma depends not only on axon regeneration or compensatory sprouting of uninjured fibers but also on the ability of newly grown axons to establish functional synapses with appropriate *** several studies have successfully promoted long-distance axonal regeneration in distinct CNS injury models,none of them have resulted in a viable therapeutic approach for patient recovery.A possible reason may be the lack of new synaptogenesis for reestablishing the circuitry lost after ***,we discuss how our understanding of the mechanisms that instruct synapse formation in the injured nervous system may contribute to the design of new strategies to promote functional restoration in traumatic CNS disorders.

关键词： viable injury instru

The impact of northern Indian Ocean rivers on the Bay of Bengal using NEMO global ocean model

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Acta Oceanologica Sinica 2020年第3期39卷 45-55页

作者： Atul Srivastava Anitha gera Imran MMomin Ashis Kumar Mitra Ankur Gupta National Centre for Medium Range Weather Forecasting Noida 201309India Jaypee University Anoopshahr Bulandshahr 203309India

The effect of river runoff over the northern Indian Ocean(NIO) especially over the Bay of Bengal(Bo B) has been studied using global Nucleus for European Modelling of the Ocean(NEMO). Two sensitivity experiments, with and without river runoff are conducted and the influence of river runoff on the Indian Ocean hydrography,stratification and circulation features are studied. It is found that due to river runoff surface salinity over the northern Bo B decreases by more than 5 and the East India Coastal Current strengthens by 2 cm/s during post monsoon season. The fresh river water reaches up to 15°N in the Bo B and is the main cause for low salinity *** surface temperature in the northwestern Bo B increases by more than 0.2℃ due to the river runoff in summer monsoon while surface cooling upto 0.2℃ is seen in north-west part of Bo B in winter season. The seasonal mixed layer depth in the region is found to be dependent on river runoff. The effect of vertical shear and Brunt Vaisala frequency on stratification is also examined. The ocean water becomes highly stratified up to 3 035 m due to the river runoff. It is found that the energy required for mixing is high in the northern and coastal Bo B.

关键词： Bay of Bengal sea surface temperature salinity mixed layer depth stratification

An Optimization Framework for Travel Pattern Interpretation of Cellular data

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International Journal of Transportation Science and Technology 2013年第3期2卷 167-182页

作者： Sarit Freund Hillel Bar-gera department of Industrial Engineering Ben-Gurion University of the Negev P.O.Box 653Beer-Sheva 84105

Collection of travel data by traditional survey methods is costly,thus limiting the amount of data being collected,as well as their frequency and *** technologies offer new types of data collection *** particular,cellular systems generate substantial amounts of data,including records regarding the connection between handsets(phones)and base stations(antenna).These records,collected by cellular service providers for various internal purposes,may provide an excellent source of information regarding travel,with several critical advantages relative to traditional travel surveys:low cost,large sample,long duration,and high response *** data has some limitations too,particularly with respect to accuracy and traveler identity;therefore,such data cannot provide a complete replacement for traditional surveys,but it can complement and enhance *** paper explores methods for identifying travel patterns from cellular data.A primary challenge in this research is to provide an interpretation of the raw data that distinguishes between activity durations and travel durations.A novel framework is proposed for this purpose,based on a grading scheme for candidate interpretations of the raw data.A genetic algorithm is used to find interpretations with high grades,which are considered as the most reasonable *** proposed method is tested on a dataset of records covering 9454 cell-phone users over a period of one *** evaluation of the resulting interpretations is presented.

关键词： antenna travel Cellular

MOdELING A SOLId BOUNdARY AS A FLUId OF INFINITE VISCOSITY

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Chinese Journal of Mechanical Engineering 2000年第1期13卷 2-9页

作者： Gingold Harry gera.dinesh West Virginia University U. S. A West Virginia University 美国

A new approach to model viscosity in the conservation of momentum equations is presented and discussed. Coefficient of viscosity is modeled in such a way that it reaches asymptotically to infinity at the solid boundary but still yields a finite value for the shear stress at the solid wall. Basic objective of this research is to show that certain combinations of higher order normal velocity gradients become zero at the solid boundary. Malled solutions for the Couette flow and Poiseuille flow between two parallel plates are obtained by modeling the coefficient of viscosity in a novel way. Also, viscous drag computed by our model is expected to yield higher values than the values predicted by the existing models, which matches closely to the experimental data.

关键词： Coefficient of viscosity Solid boundary Viscous drag