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Occurrence data may provide unreliable thermal preferences and breadth of species

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Current Zoology 2015年第6期61卷 972-982页

作者： Sara VILLEn-perez Luis M. CARRASCAL Department of Biogeography and Global Change National Museum of Natural Sciences MNCN-CSIC. C/José Gutiérrez Abascal 2 28006 Madrid Spain.

Accurate information on the thermal preference and specialization of species is needed to understand and predict spe- cies geographical range size and vulnerability to climate change. Here we estimate the position and breadth of species within thermal gradients based on the shape of the response curve of species abundance to temperature. The objective of the study is to compare the measurements of this approach based on abundance data with those of the classical approach using species＇ occur- rence data. The relationship between species＇ relative abundance and minimum winter temperature of 106 bird species wintering in the Iberian Peninsula is modeled at 100 Km2 resolution with quadratic logistic regressions. From these models we calculated the preferred temperature of species as the temperature at which the abundance is maximized, and the thermal breadth of species as the relative area under the temperature-abundance curve. We also estimated the thermal preferences and breadth of species as the average temperature and temperature range of the UTM cells in which the species are present. The abundance-temperature response curves reveal that birds prefer higher temperatures to overwinter, and are more thermally selective, than is measured by the classical approach. Moreover, response curves detect a higher inter-specific variability in both thermal preferences and ther- mal breadth of species. As occurrence data gives the same weight to cells with one or many individuals, the average temperature of the cells in which the species is present roughly reflects the average temperature in the region of study and not the environ- mental preferences of species .

关键词： Abundance-temperature response curve Birds Species occurrence Thermal breadth Thermal preferences Winter

Misfolded amyloid-βstrains and their potential roles in the clinical and pathological variability of Alzheimer’s disease

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neural Regeneration Research 2023年第1期18卷 119-120页

作者： Sara Kelley nelson perez-Urrutia Rodrigo Morales Department of neurology University of Texas Health Science Center at HoustonHoustonTXUSA Centro Integrativo de Biologia y Quimica Aplicada(CIBQA) Universidad Bernardo O’HigginsSantiagoChile

Potential causes for the clinical and pathological variability observed in Alzheimer’s disease(AD):AD is an age-related neurodegenerative disorder characterized by the impairment of cognitive functions such as memory,learning,and *** commonly described clinical symptoms are due to particular pathological changes in the brain,including inflammation,synaptic loss,and neuronal *** changes are a consequence of the accumulation of abnormally folded amyloid-β(Aβ)and tau proteins in specific areas of the central nervous *** the progressive aging of the world’s population,the number of people affected by AD is expected to substantially and consistently increase in the coming *** positions AD as one of the main public health challenges in the near future.

关键词： clinical Alzheimer amyloid

Factors associated with H pylori epidemiology in symptomatic children in Buenos Aires,Argentina

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World Journal of Gastroenterology 2006年第33期12卷 5384-5388页

作者： Cinthia Goldman Andrés Barrado Mariana Janjetic norma Balcarce Eduardo Cueto Rua Masaru Oshiro María L Calcagno Margarita Martinez Sarrasague Julián Fuda Ricardo Weill Marcela Zubillaga Guillermo I perez-perez José Boccio Radioisotopes Laboratory and Laboratory of Stable Isotopes Applied to Biology and Medicine Physics Department School of Pharmacy and Biochemistry University of Buenos Aires Buenos Aires Argentina Laboratory of Stable Isotopes Applied to Biology and Medicine Physics Department School of Pharmacy and Biochemistry University of Buenos Aires Buenos Aires Argentina Gastroenterology Unit Hospital de nios "Superiora Sor María Ludovica" La Plata Argentina Health Center Di Matteo San Fernando Buenos Aires Argentina Mathematics Department School of Pharmacy and Biochemistry University of Buenos Aires Buenos Aires Argentina Agrarian Industries Department School of Agronomy University of Morón Buenos Aires Argentina Departments of Medicine and Microbiology New York University School of Medicine New York United States

AIM： To determine prevalence of H pylori infection in symptomatic children in Buenos Aires, Argentina, and to investigate factors associated with HpyloH positivity. METHODS： A total of 395 children with upper gastrointestinal symptoms referred to the Gastroenterology Unit of the Children Hospital ＂Sor Maria Ludovica＂ were evaluated for the presence of H py/or/by the ^13C-Urea Breath Test （^13C-UBT）. A questionnaire was applied to the recruited population. RESULTS： Prevalence of H pylo H infection was 40.0% in this population （mean age 9.97 ± 3.1 years）. The factors associated with H py/or/positivity were number of siblings （P 〈 0.001）, presence of pet cats （P = 0.03） and birds （P = 0.04） in the household, and antecedents of gastritis among family members （P = 0.01）. After multivariate analysis, number of siblings [Odds ratio （OR） = 1.39; 95% CI, 1.20-1.61] and contact with pet cats （OR = 1.76; 95% CI, 1.00-3.09） remained as variables associated with H pylori infection. COnCLUSIOn： The prevalence of H pylori infection in children with upper gastrointestinal symptoms in Argentina was similar to that reported in developed countries. Children from families with a higher crowding index and presence of pet cats have a higher risk of being colonized with Hpylori.

关键词： H pylori Children Epidemiology Urea breathtest Prevalence

Woodland Mediterranean birds can resist a dry extreme cold wave

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Current Zoology 2014年第4期60卷 429-437页

作者： Sara VILLEn-perez Luis M. CARRASCAL Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (CSIC) C/Jos6 Guti6rrez Abascal 228006 Madrid Spain

The ecological consequences of climate extreme events are still poorly understood, especially those related to cold episodes. Winter cold spells might imperil the energy balance of small passerines, thus compromising their survivorship. Here we analyze how the abundance and habitat use of three tree-gleaning passerine species wintering in a montane oakwood of central Spain at ca. 1,300 m a.s.1, was influenced by the cold wave that hit Europe in February 2012. We monitored temperature, wind and the relative abundance of great tit Parus major, blue tit Cyanistes caeruleus and long-tailed tit Aegithalos caudatus in 15 plots throughout three periods： before, during and after the cold wave. Our results clearly rule out widespread mortality and temporal migration of the studied passerine populations, as the abundance of these species did not diminish during the cold wave. Moreover, the species usually foraging higher in the tree canopy -and thus more exposed to windmoved to the less windy woodland plots （long-tailed tit） and reduced their foraging height above ground during the cold wave （long-tailed tit and blue tit）, probably to mitigate the deleterious effects of wind chill. Therefore, these forest birds were able to cope with a dry cold wave that was statistically extreme in terms of temperature and wind chill, according to the historic climate records of the region. It seems that, at least when foraging substrates are not heavily covered by snow or ice, Mediterranean birds can resist an extreme cold wave [Current Zoology 60 （4）： 429-437, 2014].

关键词： Cold wave Harsh weather Mediterranean oakwoods Temperature Tree-gleaning birds Wind chill

Role of chromosomal instability and clonal heterogeneity in the therapy response of breast cancer cell lines

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Cancer Biology & Medicine 2020年第4期17卷 970-985页

作者： natalia Vargas-Rondon Erika perez-Mora Victoria E.Villegas Milena Rondon-Lagos School of Biological Sciences Universidad Pedagogica y Tecnologica de ColombiaTunja 150003Colombia Biology Program Faculty of Natural SciencesUniversidad del RosarioBogota 111221Colombia

Objective:Chromosomal instability(CIn)is a hallmark of cancer characterized by cell-to-cell variability in the number or structure of chromosomes,frequently observed in cancer cell populations and is associated with poor prognosis,metastasis,and therapeutic *** cancer(BC)is characterized by unstable karyotypes and recent reports have indicated that CIn may influence the response of BC to chemotherapy ***,paradoxical associations between extreme CIn and improved outcome have been ***:This study aimed to 1)evaluate CIn levels and clonal heterogeneity(CH)in MCF7,ZR-751,MDA-MB468,BT474,and KPL4 BC cells treated with low doses of tamoxifen(TAM),docetaxel(DOC),doxorubicin(DOX),Herceptin(HT),and combined treatments(TAM/DOC,TAM/DOX,TAM/HT,HT/DOC,and HT/DOX)by using fluorescence in situ hybridization(FISH),and 2)examine the association with response to treatments by comparing FISH results with cell ***:Intermediate CIn was linked to drug sensitivity according to three characteristics:estrogen receptorα(ERα)and HER2 status,pre-existing CIn level in cancer cells,and the CIn induced by the ***α+/HER2-cells with intermediate CIn were sensitive to treatment with taxanes(DOC)and anthracyclines(DOX),while ERα-/HER2-,ERα+/HER2+,and ERα-/HER2+cells with intermediate CIn were resistant to these ***:A greater understanding of CIn and CH in BC could assist in the optimization of existing therapeutic regimens and/or in supporting new strategies to improve cancer outcomes.

关键词： Breast cancer chromosomal instability therapy resistance FISH clonal heterogeneity

Oxidation and Coatings for Power Generation： new Super Ultra Critical Steam Turbines

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中国腐蚀与防护学报 2009年第4期29卷 318-319页

作者： F. J. perez Grupo de Investigacion de Ingenieria de Superficies y Materiales nanoestructurados U. C. M. n°910627 Facultad de Ciencias Quimicas Universidad Complutense de Madrid. 28040 Madrid Spain

The steels with chromium contents between 9%and 12%wt are used for power plants with advanced steam oxidation *** present good creep properties as 9%Cr steels and good oxidation resistance,at the temperatures range between 500℃～600℃.In the last years numerous investigation in development of coatings has been realized with the aim the protected them against the oxidation in order to allow operation of steam turbines at 650℃.In this study,Al-Hf protective coatings were deposited by CVD-FBR on ferritic steel HCM-12A followed by a diffusion heat treatment,have shown to be protective at 650℃under steam for at least 3000 hours of laboratory steam exposure under atmospheric *** and composition of coatings were characterized by different techniques, such as scanning electron microscopy(SEM),electron probe microanalysis,and X-ray diffraction(XRD). On the other hand,volatile species by mass spectrometry(MS) and thermogravimetric measurements (TG) during the initial stages oxidation of the P92 ferritic steel without and of Al and Al/Si coating by chemical vapour deposition in fluidized bed reactors(CVD-FBR) at 650℃in Ar+20%H_2O for 150 h were *** order to go forward to coatings design the Thermocalc code is used as base for the MSdata. TG-MS experiments were conducted in a closed steam loop in order to obtain information about the oxyhydroxides formation as reaction between coatings and *** those results the role of the different coating element could be established and optimized for the coating *** oxidation mechanism based on the TG-MS results is *** morphology/composition and structure of the oxidized samples were also studied using SEM/EDS and XRD techniques.

关键词：氧化金属腐蚀防护

Driving Factors for Forest Fire Occurrence in Durango State of Mexico:A Geospatial Perspective

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Chinese Geographical Science 2010年第6期20卷 491-497页

作者： Diana Avila-Flores Marin Pompa-Garcia Xanat Antonio-nemiga Dante A Rodriguez-Trejo Eduardo Vargas-perez Javier Santillan-perez Forestry Division University of Chapingo Faculty of Forestry Juarez University of the State of DurangoRio Papaloapan and Durango Blvd Faculty of Geography Autonomous University of Mexico StateCerro de Coatepec s/nCiudad Universitaria

Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management *** the driving factors and understanding the contribution of each factor are essential for the management of forest fire *** objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,*** this purpose,data from forest fire records for a five-year period were *** spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square *** show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory *** addition,vegetation type and precipitation are also the main driving *** fitting model indicates obvious link between the *** fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire *** regulation of human activities is a key strategy for forest fire prevention.

关键词： forest fire Geographically Weighted Regression(GWR) land use forest management Durango State Mexico

Egg CD9 protein tides correlated with sperm oscillations tune the gamete fusion ability in mammal

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Journal of Molecular Cell Biology 2018年第6期10卷 494-502页

作者： Benjamin Ravaux Sophie Favier Eric perez and Christine Gourier Laboratoire de Physique Statistique Ecole Normale Superieure/PSL Research UniversityUPMC Univ Paris 06Universite Paris DiderotCNRS75005 ParisFrance

Mammalian fertilization involves membrane events-adhesion,fusion,sperm engulfment,membrane block to polyspermy-whose causes remain largely ***,specific oscillations of the sperm in contact with the egg were shown to be necessary for *** a microfluidic chip to impose the venue for the encounter of two gametes allowed real-time observation of the membrane remodelling occurring at the sperm/egg *** spatiotemporal mapping of egg CD9 revealed that this protein concentrates at the egg/sperm interface as a result of sperm oscillations,until a CDg-rich platform is nucleated on which fusion immediately takes *** 2-5 min after fusion,most of the CD9 leaves the egg for the external aqueous *** an egg membrane wave engulfs the sperm head in^25 *** results show that sperm oscillations initiate the CD9 recruitment that causes gamete fusion after which CD9 and associated proteins leave the membrane in a process likely to contribute to block *** highlight that the gamete fusion story in mammals is an unexpected interplay between mechanical constraints and proteins.

关键词： mammalian fertilization membrane dynamics real-time imaging CDg sperm oscillations gamete fusion

Glial kon/nG2 gene network for central nervous system repair

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neural Regeneration Research 2017年第1期12卷 31-34页

作者： Maria Losada-perez neale Harrison Alicia Hidalgo School of Biosciences University of BirminghamBirminghamEnglandUK Universidad Autonoma de Madrid MadridSpain

The glial regenerative response to central nervous system（CnS） injury,although limited,can be harnessed to promote regeneration and *** provokes the proliferation of ensheathing glial cells,which can differentiate to remyelinate axons,and partially restore *** response is evolutionarily conserved,strongly implying an underlying genetic *** mammals,it is elicited by nG2 glia,but most often newly generated cells fail to *** an important goal had been to find out how to promote glial differentiation following the proliferative response.A gene network involving notch and prospero（pros） controls the balance between glial proliferation and differentiation in flies and mice,and promotes CnS repair at least in fruit-flies.A key missing link had been how to relate the function of nG2 to this gene *** findings by Losada-perez et al.,published in JCB,demonstrated that the Drosophila nG2 homologue kon-tiki（kon） is functionally linked to notch and pros in *** engaging in two feedback loops with notch and Pros,in response to injury,Kon can regulate both glial cell number and glial shape homeostasis,essential for *** offers powerful genetics to unravel the control of stem and progenitor cells for regeneration and repair.

关键词： nG2 kon-tiki glia Drosophila injury regeneration repair CnS