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Main environmental variables influencing the abundance of plant species under risk category

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Journal of Forestry Research 2022年第4期33卷 1209-1217页

作者： Pablo antúnez División de Estudios de Posgrado Universidad de la Sierra Juárez68725 Oax.México

Determining climatic and physiographic variables in Mexico’s major ecoregions that are limiting to biodiversity and species of high conservation concern is essential for their ***,at the national level to date,few studies have been performed with large data sets and crossconfirmation using multiple statistical ***,we used 25 endemic,rare and endangered species from 3610 sampling points throughout Mexico and 25 environmental attributes,including average precipitation for different seasons of the year,annual dryness index,slope of the terrain;and maximum,minimum and average temperatures to test our hypothesis that these species could be assessed with the same weight among all variables,showing similar indices of *** results using principal component analysis,covariation analysis by permutations,and random forest regression showed that summer precipitation,length of the frost-free period,spring precipitation,winter precipitation and growing season precipitation all strongly influence the abundance of tropical *** contrast,annual precipitation and the balance at different seasons(summer and growing season)were the most relevant variables on the temperate region *** dry areas,the minimum temperature of the coldest month and the maximum temperature of the warmest month were the most significant *** these different associations in different climatic regions could support a more precise management and conservation plan for the preservation of plant species diversity in forests under different global warming scenarios.

关键词： Correlative models Climate change Effect of topography Endemic species IUCN list Machine learning algorithms

Numerical simulation and analysis of water flow over stepped spillways

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Science China(Technological Sciences) 2009年第7期52卷 1958-1965页

作者： AMADOR antónio Hydraulic and Environmental Department Technologic School of Barreiro Barreiro 2830-144 Portugal

Numerical simulation of water flow over the stepped spillway is conducted using Mixture multiphase flow model. Different turbulence models are chosen to enclose the controlling equations. The turbulence models investigated are realizable k-ε model, SST k-ω model, v2-f model and LES model. The computational results by the four turbulence models are compared with experimental ones in the following aspects: mean velocity, the spanwise vorticity and the growth of the turbulent boundary layer thickness in the streamwise direction. It is found from the comparison that the realizable k-ε model, in which the rotation tensor is included, shows good performance for simulation of flows involving rotation, boundary layer and recirculation. The realizable k-ε model is the most efficient in simulating flow over stepped spillways. Further, the characteristics of water flow on the stepped spillway are studied in terms of the mean velocity profile normal to the pseudo-bottom and the pressure field on the steps based on the simulation results using realizable k-ε model.

关键词： stepped spillway turbulence model numerical simulation boundary layer

Calculations of Optical Rotation from Density Functional Theory

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Chinese Physics Letters 2007年第5期24卷 1207-1209页

作者： antǒnio Canal Neto Francisco Elias Jorge Departamento de Fisica Universidade Federal do Espírito Santo 29060-900 Vitória ES Brazil

Density function theory calculations of frequency-dependent optical rotations [α]ω for three rigid chiral molecules are reported. Calculations have been carried out at the sodium D line frequency, using the ADZP basis set and a wide variety of functionals. Gauge-invariant atomic orbitals are used to guarantee origin-independent values of [ω]D. In addition, study of geometry dependence of [ω]D is reported. Using the geometries optimized at the B3LYP/ADZP level, the mean absolute deviation of B3LYP/ADZP and experimental laiD values yields 60.1°/（dm g/cm^3）. According to our knowledge, this value has not been achieved until now with any other model.

关键词： MOLECULAR WAVE-FUNCTIONS BASIS-SETS MP2 HF

Generalized Hardy Spaces

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Acta Mathematica Sinica,English Series 2010年第9期26卷 1673-1692页

作者： Alexandre ALMEIDA antónio M.CAETANO Departamento de Matemática Universidade de Aveiro

Hardy spaces with generalized parameter are introduced following the maximal characterization approach. As particular cases, they include the classical Hp spaces and the Hardy-Lorentz spaces H^p,q. Real interpolation results with function parameter are obtained, Based on them, the behavior of some classical operators is studied in this generalized setting.

关键词： Generalized Hardy spaces maximal functions Poisson kernel interpolation with function parameter Riesz potentials singular integrals

Small dams/reservoirs site location analysis in a semi-arid region of Mozambique

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International Soil and Water Conservation Research 2021年第3期9卷 381-393页

作者： antònio dos Anjos Luís Pedro Cabral Department of GIS and Regional Planning Universidade Catdlica de MozambiqueBeiraSofalaMozambique NOVA Information Management School(NOVA IMS) Universidade Nova de Lisboa1070-312LisboaPortugal

The water crisis is one of the biggest human problems in developing countries,especially in semi-arid regions where it can form an obstacle to irrigation and cultivation,cattle raising and people's *** construction of small dams/reservoirs are a possible solution to remediate this *** infrastructures must be located in suitable areas to be *** study aimed to find the most suitable locations for small dams/reservoirs in the Tete province region,Mozambique,which has a pronounced water deficit A Geographical Information System(GIS)based approach was used to implement a multicriteria evaluation(MCE)analysis through an Analytic Hierarchical Process(AHP),which included local experts’*** main categories of suitability were identified:"Not suitable”(15%of total area),"Modestly suitable"(78%),and“Suitable"(7%).We found that 35 of the 38(92%)abandoned small dams/reservoirs were in areas classified as“Modestly suitable”confirming the robustness of our *** also found that most of the dams/reservoirs currently operating(78%)and planned(73%)are in modestly suitable *** finding suggests that the decision to construct dams/reservoirs may not have considered the most critical suitability factors identified in this *** data and/or additional criteria are required for the full understanding of finding out why so many dams/reservoirs failed before building new ones to address the population’s water needs in the region.

关键词： Water scarcity Multi-criteria evaluation Geographic information systems Remote sensing Mozambique

Aggregate Development and Organic Matter Storage in Mediterranean Mountain Soils

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Pedosphere 2010年第6期20卷 702-710页

作者： R.M.POCH M.antúNEZ Department of Environment and Soil Science University of Lleida. Centre Tecnològic Forestal de Catalunya

Soil aggregation and organic matter of soils from the pre-Pyrenean range in Catalonia (NE Spain) were studied,in order to assess their quality as carbon sinks and also to select the best soil management practices to preserve their *** stability,organic carbon and micromorphology were *** highest amount of organic carbon was found in alluvial,deep soils (228 Mg C ha -1 ),and the lowest was in a shallow,stony soil with a low plant cover (78 Mg C ha -1 ).Subsurface horizons of degraded soils under pastures were the ones with smaller and less-stable *** residues of organic matter (OM) were found mostly in interaggregate *** the aggregates there were some organic remains that were beginning to decompose,and also impregnative nodules of amorphous *** OM was evenly distributed among the aggregate fractions,the larger blocky peds had more specific surface,contained less decomposed OM and had a lower organic/mineral interphase than smaller crumb aggregates,which were also more *** carbon storage was affected primarily by the OM inputs in the surface *** order to store organic carbon over the mid- and long-term periods,the mechanisms favouring structuration through biological activity and creating small aggregates with intrapedal stable microporosities seemed to be the most effective.

关键词： aggregate stability Catalonia macroaggregates organic carbon soil carbon storage

Morpholino studies shed light on the signaling pathways regulating axon regeneration in lampreys

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Neural Regeneration Research 2022年第7期17卷 1475-1477页

作者： Daniel Sobrido-Cameán antón Barreiro-Iglesias Department of Functional Biology Faculty of BiologyCIBUSUniversidade de Santiago de CompostelaSantiago de CompostelaA CoruñaSpain Department of Zoology University of CambridgeCambridgeUK

Lampreys are one of the most ancient extant vertebrates and they have become an animal model of interest for the study of spontaneous axon regeneration after a traumatic central nervous system *** to most mammals,lamp... 详细信息

关键词： traumatic regeneration injury

Role of short chain fatty acids in gut health and possible therapeutic approaches in inflammatory bowel diseases

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World Journal of Clinical Cases 2022年第28期10卷 9985-10003页

作者： Marcos antônio Ferreira Caetano Patricia Castelucci Department of Anatomy Institute of Biomedical SciencesUniversity of São PauloSão Paulo 05508900SPBrazil

Inflammatory bowel diseases(IBDs) are characterized by inflammation in the gastrointestinal tract and include Ulcerative Colitis and Crohn’s *** diseases are costly to health services,substantially reduce patients’ quality of life,and can lead to complications such as cancer and even *** include abdominal pain,stool bleeding,diarrhea,and weight *** treatment of these diseases is symptomatic,seeking disease *** intestine is colonized by several microorganisms,such as fungi,viruses,and bacteria,which constitute the intestinal microbiota(IM).IM bacteria promotes dietary fibers fermentation and produces short-chain fatty acids(SCFAs) that exert several beneficial effects on intestinal *** can bind to G protein-coupled receptors,such as GPR41 and GPR43,promoting improvements in the intestinal barrier,anti-inflammatory,and antioxidant ***,SCFAs could be a therapeutic tool for ***,the mechanisms involved in these beneficial effects of SCFAs remain poorly ***,this paper aims to provide a review addressing the main aspects of IBDs,and a more detailed sight of SCFAs,focusing on the main effects on different aspects of the intestine with an emphasis on IBDs.

关键词： Ulcerative colitis Crohn’s disease Short-chain fatty acid Butyrate Inflammatory bowel diseases Free fatty acid receptor

Effect of pier shape and pier alignment on the equilibrium scour depth at single piers

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International Journal of Sediment Research 2016年第3期31卷 244-250页

作者： Cristina Fael Rui Lana antónio Cardoso Faculdade de Engenharia Universidade da Beira InteriorEdificio Ⅱ das EngenhariasCalcada Fonte da Lameiro Instituto Superior de Engenharia/Universidade do Algarve Instituto Superior Tecnico Universidade de Lisboa

The equilibrium scour depth at uniform single bridge piers depends on a large number of variables,including the pier horizontal cross-section shape and its alignment angle towards the flow *** influence of these variables has been studied by only a few researchers,mostly,on the basis of tests that were far from approaching *** experimental study aims at revisiting the influence of piers’ shape and alignment on local scouring for length-width ratios smaller than or equal to 4,by increasing the experimental *** five long-duration laboratory tests were run under steady,clear-water flow,close to the threshold for initiation of sediment *** pier shapes were considered:circular,rectangular square-nosed,rectangular round-nosed,oblong,and zero-spacing(packed) pile-groups;the tested skew-angles were 0°,30°,45°,60°,and 90°.It was concluded that i) the shape factor can be taken as 1.0,for rectangular round-nosed and oblong cross-section piers,and as 1.2,for rectangular squarenosed and packed pile-group cross-section piers,ii) the shape factor does not vary significantly with the duration of tests,this way confirming the robustness of the shape factors reported to date,iii) the effect of shape is present at skewed piers although the associated coefficients remain in the narrow range of1.0-1.2,and iv) for length-width ratios smaller than 4,the shape factor is of the same order of magnitude as the skew angle factor and should not be neglected.

关键词： Scour Pier shape Pier alignment