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Species,growth form,and biogeographic diversity of summit vegetation along an elevation gradient in the tropical Andes:a baseline for climate change monitoring

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Journal of Mountain Science 2022年第12期19卷 3441-3457页

作者： Luis D.LLAMBI Luis e.GAMeZ Roxibell PeLAYO Carmen J.AZOCAR Jesus e.torres Nelson J.MARQUeZ Monica B.BeRDUGO Francisco CUeSTA Lirey A.RAMIReZ Institute of environmental and ecological Sciences(ICAe) University of Los AndesMérida5101Venezuela Consorcium for Susteinable Development of the Andean eco-Region(CONDeSAN) Calle Germán Alemán E12-123Quito170504Ecuador Laboratory of Dendrology Environmental and Forestry FacultyUniversity of Los AndesMérida5101Venezuela ecological Plant Geography Faculty of GeographyUniv.of MarburgDeutschhausstrasse 10Marburg35032Germany Group of Biodiversity Environment and Health Research(BIOMAS)University of Las AméricasQuito170125Ecuador

Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate *** understanding spatiotemporal changes in plant species composition,richness and community structure along tropical alpine altitudinal gradients is of primary importance,both the functional and historical/biogeographic dimensions of vegetation diversity remain largely *** used Generalized Linear Models and multivariate analyses to assess changes in species,growth forms,and biogeographic groups richness and abundance,in response to habitat variables along an elevation gradient in seven summits(3800 to 4600 m asl)in the Venezuelan Andes,studied using the standardized approach of the GLORIA-Andes monitoring *** habitat variables assessed were soil temperature(-10 cm),soil organic matter,slope inclination,and substrate *** found 113 species,representing72 genera,32 families,13 growth forms,and seven biogeographic origins,that included 25%of endemic *** observed richer vegetation,both in terms of species and growth forms,in summits with higher soil temperatures and higher SOM content,as well as higher biogeographic origin richness with increasing soil *** presence of holarctic elements increased toward higher elevations,while the occurrence of austral antarctic elements increased toward lower *** results indicate that biogeographic and functional approaches to vegetation diversity capture well the effect of abiotic filtering on community structuring in these tropical alpine *** findings constitute an important baseline for monitoring vegetation dynamics linked to climate change in the Venezuelan Andes by highlighting the functional and historical perspective on vegetation analyses,in contrast with more traditional approaches,based only on taxonomic species diversity.

关键词： Alpine vegetation Biogeography elevation gradient Functional diversity Páramo Soil organic matter Temperature Tropical Andes

Prevalence of vacA, cagA and babA2 genes in Cuban Helicobacter pylori isolates

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World Journal of Gastroenterology 2009年第2期15卷 204-210页

作者： Lino e.torres Karelia Melián Arlenis Moreno Jordis alonso Carlos A Sabatier Mayrín Hernández Ludisleydis Bermúdez Boris L Rodríguez Department of Microbiology and Immunology Biotechnology Division National Centre for Scientif ic Research Ciudad de La Habana Cuba Department of Gastroenterology Medical and Chirurgic Research Centre (CIMEQ) Ciudad de La Habana Cuba Anatomopathology Department Medical and Chirurgic Research Centre (CIMEQ) Ciudad de La Habana Cuba

AIM： To investigate the prevalence of vacuolating cytotoxin （vacA）, cytotoxin associated gene A （cagA） and blood adhesion binding antigen （babA2） genotypes of Helicobacter pylori （H pylori） isolates from Cuban dyspeptic patients. MeTHODS： DNA was extracted from Hpylori-positive cultures taken from 130 dyspeptic patients. Genotyping was performed by PCR, using specific primers for vacA （s1, s2, m1, m2）, cagA and babA2 genes. endoscopic observations and histological examinations were used to determine patient pathologies. ReSULTS： vacA alleles s1, s2, m1 and m2 were detected in 96 （73.8%）, 34 （26.2%）, 75 （57.7%） and 52 isolates （40%）, respectively, while the cagA gene was detected in 95 isolates （73.2%）. One hundred and seven isolates （82.3%） were babA2-positive. A significant correlation was observed between vacAs1m1 and cagA and between vacAs1ml and babA2 genotypes （P 〈 0.001 and P 〈 0.05, respectively） and between babA2 genotype and cagA status （P 〈 0.05）; but, no correlation was observed between vacAsl and babA2 genotypes. eighty five （65.4%） and 73 （56.2%） strains were type 1 （vacAsl-cagA-positive） and ＂triplepositive＂（vacAs1-cagA-babA2-positive）, respectively, and their presence was significantly associated with duodenal ulcer （P 〈 0.01 and P 〈 0.001, respectively）. CONCLUSION： The distribution of the main virulence factors in the Cuban strains in this study resembled that of the Western-type strains, and the more virulent H pylori isolates were significantly associated with duodenal ulcer, ulcer disease being the worst pathology observed in the group studied.

关键词： Cuban dyspeptic patients He/icobacterpylori vacA, cagA and babA

elenoside increases intestinal motility

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World Journal of Gastroenterology 2006年第44期12卷 7143-7148页

作者： e Navarro SJ alonso R Navarro J Trujillo e Jorge Department of Pharmacology Faculty of Medicine University of La Laguna 38071 La Laguna Apdo. 55 Tenerife Canary Islands Spain Department of Medical and Chirurgical Sciences University of Las Palmas Gran Canaria Canary Islands Spain Centro de Productos Naturales y Agrobiologia CSIC Tenerife Canary Islands Spain

AIM： TO study the effects of elenoside, an arylnaphthalene lignan from Justicia hyssopifolia, on gastrointestinal motility in vivo and in vitro in rats. MeTHODS： Routine in vivo experimental assessments were catharsis index, water percentage of boluses, intestinal transit, and codeine antagonism. The groups included were vehicle control （propylene glycol-ethanolplant oil-tween 80）, elenoside （i.p. 25 and 50 mg/kg）, cisapride （i.p. 10 mg/kg）, and codeine phosphate （intragastric route, 50 mg/kg）. In v/tro approaches used isolated rat intestinal tissues （duodenum, jejunum, and ileum）. The effects of elenoside at concentrations of 3.2 ×10^4, 6.4 ×10^4 and 1.2 ×10^3 mol/L, and cisapride at 10^6 mol/L were investigated. ReSULTS： elenoside in vivo produced an increase in the catharsis index and water percentage of boluses and in the percentage of distance traveled by a suspension of activated charcoal. Codeine phosphate antagonized the effect of 25 mg/kg of elenoside. In vitro, elenoside in duodenum, jejunum and ileum produced an initial decrease in the contraction force followed by an increase. elenoslde resulted in decreased intestinal frequency in duodenum, jejunum, and ileum. The in vitro and in vivo effects of elenoside were similar to those produced by cisapride. CONCLUSION： elenoside is a lignan with an action similar to that of purgative and prokinetics drugs. elenoside, could be an alternative to cisapride in treatment of gastrointestinal diseases as well as a preventive therapy for the undesirable gastrointestinal effects produced by opioids used for mild to moderate pain.

关键词： elenoside Gastrointestinal motility, Smail intestine preparation

Numerical analysis of rapid drawdown: Applications in real cases

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Water Science and engineering 2016年第3期9卷 175-182页

作者： eduardo e. alonso Nuria M. Pinyol Department of Civil and environmental engineering Universitat Politecnica de Catalunya (UPC) Barcelona 08034 Spain Centre Internacional de Metodes Numerics en enginyeria (CIMNe) Barcelona 08034 Spain

In this study, rapid drawdown scenarios were analyzed by means of numerical examples as well as modeling of real cases with in situ measurements. The aim of the study was to evaluate different approaches available for calculating pore water pressure distributions during and after a drawdown. To do that, a single slope subjected to a drawdown was first analyzed under different calculation alternatives, and numerical results were discussed. Simple methods, such as undrained analysis and pure flow analysis, implicitly assuming a rigid soil skeleton, lead to significant errors in pore water pressure distributions when compared with coupled flow-deformation analysis. A similar analysis was performed for the upstream slope of the Glen Shira Dam, Scotland, and numerical results were compared with field measurements during a controlled drawdown. Field records indicate that classical undrained calculations are conservative but unrealistic. Then, a recent case of a major landslide triggered by a rapid drawdown in a reservoir was interpreted. A key aspect of the case was the correct characterization of permeability of a representative soil profile. This was achieved by combining laboratory test results and a back analysis of pore water pressure time records during a period of reservoir water level fluctuations. The results highlight the difficulty of predicting whether the pore water pressure is overestimated or underestimated when using simplified approaches, and it is concluded that predicting the pore water pressure distribution in a slope after a rapid drawdown requires a coupled flow-deformation analysis in saturated and unsaturated porous media.

关键词： Hydro-mechanical coupling Coupled flow-deformation analysis Numerical analysis Drawdown Landslide Pore water pressure

Parameters Affecting the Fuel Cell Reactions on Platinum Bimetallic Nanostructures

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electrochemical energy Reviews 2023年第1期6卷 830-853页

作者： Nicolas alonso‑Vante IC2MP UMR-CNRS 7285University of Poitiers4 rue Michel Brunet86072 PoitiersFrance

In this paper the electrochemical properties of some platinum-based nanoalloys are *** revision is centered on electrocatalytic materials generated via the carbonyl chemical route(CCR).In considering the effects of segregation in these bimetals,the reaction of the hydrogen oxidation(HOR)and oxygen reduction(ORR)in the alkaline medium was *** reaction kinetics of these electrochemical processes in the alkaline electrolyte is still a *** the design of high-performance platinum-based electrocatalysts,it is of importance to know that the kinetics of HOR and ORR also depends on the Pt *** electrochemical analysis,based on the study of Pt nanoalloyed surfaces with different Pt-adsorbate interactions,was taken into account.A clear trend in the HOR as well as the ORR activity,in the alkaline electrolyte,was established,revealing that the activity changes in the order PtSn/Ce former,and for the latter Pt/C(Tek)ecisive effect of the Pt-H_(ad)energy on the HOR kinetics on Pt surfaces apparently depends on the oxophilicity role of the metal to favor M-OH_(ad).The apparent electronic effect is not evident on these materials,except if a strong metal interaction is induced per se with either the carbon or oxide supports,e.g.,the Pt/SnO_(2)-C interface in acidic *** effects of Pt-H_(ad)energy on HOR kinetics were found with the oxophilicity of the sp^(2)domains of carbon that serve as anchoring or nucleation sites for platinum *** results were compared with the literature data,and it turns out that this type of strong metal support interaction(SMSI)modification is favorably induced by UV–VIS irradiation and outperforms Pt-Mmaterials to some *** for HOR or ORR,it is shown that non-noble metals not only act as a surrogate metal for Pt utilization by inducing a compressive stress effect between the Pt atoms in the outermost layer but also participat

关键词： electrocatalysts HOR HeR ORR Pt-based materials Bimetallic Carbon domains

Could mammalian inorganic polyphosphate be a crucial signaling molecule in neurological disorders?

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Neural Regeneration Research 2024年第4期19卷 701-702页

作者： Renata torres Da Costa Maria e.Solesio Rutgers University Department of BiologyCamdenNJUSA

Since the early stages of life on earth,cellular metabolism has evolved to adapt to fluctuations in nutrient and oxygen *** this context,mammals,which are probably the organisms that show one of the highest levels of metabolic complexity,have developed an elegant system that uses constant and rechargeable energy sources of modulate their *** homeostasis is especially important in the central nervous system,as neurons and other cells in the brain are highly susceptible to fluctuations in nutrients and oxygen availability.

关键词： metabolism homeostasis neurological

NeCAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael K.e.Schafer Sudena Wang Michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal eF-hand calcium-binding proteins 1–3(NeCAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one eF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NeCAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NeCAB2 interacts with predominantly striatal G-protein-coupled receptors, while NeCAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NeCAB proteins exhibit distinct subcellular localizations: NeCAB1 is found in the nucleus and cytosol, NeCAB2 resides in endosomes and the plasma membrane, and NeCAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NeCAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NeCAB proteins by controlling the availability of protein–protein interaction domains situated between the eF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium eF hand mitochondria nervous system signal transduction

Behavior of materials for earth and rockfill dams:Perspective from unsaturated soil mechanics

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Frontiers of Structural and Civil engineering 2010年第1期4卷 1-39页

作者： eduardo e.alonso Rafaela CARDOSO Universidad Politécnica de Cataluña BarcelonaSpain Instituto Superior Técnico LisbonPortugal

The basis of the design of earth and rockfill dams is focused on ensuring the stability of the structure under a set of conditions expected to occur during its *** mechanical and hydraulic conditions must be considered since pore pressures develop during construction,after impoundment and in *** instability phenomena caused by transient flow and internal erosion must be *** prediction of the hydromechanical behavior of traditional and non-traditional materials used in the construction of dams is therefore *** materials used for dam’s construction cover a wide range from clayey materials to *** a broad sense they are compacted materials and therefore unsaturated materials.A summary of the current level of knowledge on the behavior of traditional materials used in the construction of dams is presented in the *** compacted materials(with a significant clay fraction),rockfill and compacted soft rocks are studied with more *** latter are non-traditional *** are analysed because their use,as well as the use of mixtures of soil and rock,is becoming more necessary for sustainability reasons.

关键词： dams unsaturated soil mechanics suction rockfill clayey soil mixture

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工程屏障中的气体迁移(英文)

岩石力学与工程学报 2006年第4期25卷 693-708页

作者： eduardo e. alonso 加泰罗尼亚理工大学(UPC)岩土工程系

建立了高放废物工程屏障体系变形与二相流(偏重于气体迁移)的耦合模型。同时,介绍模型的创新点,在于引入了由变形有关的可变渗透性界面来模拟回填材料和坚硬岩石或混凝土结构之间的关系。压力、应力和体积含水量的计算结果与实测值的对... 详细信息

建立了高放废物工程屏障体系变形与二相流(偏重于气体迁移)的耦合模型。同时,介绍模型的创新点,在于引入了由变形有关的可变渗透性界面来模拟回填材料和坚硬岩石或混凝土结构之间的关系。压力、应力和体积含水量的计算结果与实测值的对比较吻合。研究结果表明:此模型可精确描述在大规模现场试验中的真实过程。

关键词：高放废物含砂膨润士废物处理气体迁移原位试验本构模型反分析