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Journal of Mountain Science 2016年第7期13卷 1139-1153页

作者： José Antonio lópez-SáEZ Francisca AlBA-SáNCHEZ sandra robles-lópez Sebastián PéREZ-DíAZ Daniel ABEl-SCHAAD Silvia SABARIEGO-RUIZ Arthur GlAIS Research Group Archaeobiology Institute of History CSIC Dept.Botany Faculty of Sciences University of Granada Dept.of Plant Biology Faculty of Biology Complutense University lETG CAEN GEOPHEN-UMR 6554 CNRS University of Caen-Normandie

A high-altitude peat sequence from the heart of the Spanish Central System(Gredos range) was analysed through a multi-proxy approach to determine the sensitivity of high-mountain habitats to climate, fire and land use changes during the last seven hundred years, providing valuable insight into our understanding of the vegetation history and environmental changes in a mountain pass close to a traditional route of transhumance. The pollen data indicate that the vegetation was dominated by shrublands and grasslands with scattered pines in high-mountain areas, while in the valleys cereals, chestnut and olive trees were cultivated. Strong declines of high-mountain pines percentages are recorded at 1540, 1675, 1765, 1835 and 1925 cal AD, which may be related to increasing grazing activities and/or the occurrence of anthropogenic fires. The practice of mountain summer farming and transhumance deeply changed and redesigned the landscape of the high altitudes in central Spain(Gredos range) since the Middle Ages, although its dynamics was influenced in some way by climate variability of the past seven centuries.

关键词： Climate and human impacts Fire late Holocene Gredos range Vegetation history

The anthocyanin's role on the food metabolic pathways,color and drying processes:An experimental and theoretical approach

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Food Bioscience 2022年第3期47卷 91-110页

作者： sandra Peñaloza Cornelio Delesma Jesús Muñiz lópez-Ortiz A. Instituto de Energías Renovables Universidad Nacional Autónoma de MéxicoPriv.Xochicalco s/nCol.CentroTemixco62580MorelosMexico

This review is intended to cover the works related to the anthocyanin behavior in food that is subjected to *** experimental and theoretical results available in scientific literature are *** increase in anthocyanin concentration has been observed upon thermal ***,a conclusive explanation is still *** accessible studies suggest an increase in concentration during maturations,which could be related to the enzymatic *** possible enzymes involved in such a procedure have also been covered,including their role played in the *** possible activation mechanisms and the related factors such as temperature,pH,oxygen contents and the presence of UV-light irradiation were also ***,the metabolic pathways were also explored including experimental evaluation and theoretical models based on atomistic methodologies such as density functional theory(DFT).This review is aimed to provide a comprehensive overview of the probable mechanisms behind the increase of anthocyanin concentration during drying.

关键词： Anthocyanin Metabolic pathway PAl CHS UFGT HPlC Theoretical model

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ANCIENT EGYPT

Journal of Ancient Civilizations 2019年第1期34卷 83-111,127页

作者： sandra l.lippert CNRS ASM 5140Montpellier

The last 15 years or so have seen a marked increase in the publication of handbooks,manuals,lexica and encyclopaedia on various academic disciplines and *** consequence is that overview articles on ancient Egyptian law have also ***,the scope and content of such articles and chapters depend on the one hand on the expectations,specifications and word count parameters given by the editors,and on the other on the individual take of the *** five chapters1 by Richard Jasnow and Joe Manning that add up to almost 240 pages,Egyptian law fully takes its place alongside other Near Eastern legal systems in the chronologically ordered Handbook of Oriental Studies(HdO)double volume edited by Ray Westbrook,and the only reproach that one might find with the quasi-exhaustive handling of the subject is that the citations favour secondary literature over text editions and thus complicate access to the primary sources.

关键词： legal law Eastern

Diversity of dictyostelid social amoebae in high latitude habitats of Northern Sweden

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Fungal Diversity 2013年第1期58卷 185-198页

作者： Allison l.Perrigo sandra l.Baldauf Maria Romeralo Program in Systematic Biology Department of Organismal BiologyEvolutionary Biology CenterUppsala UniversityNorbyvägen 18D75236 UppsalaSweden

The dictyostelid social amoebae(Dictyostelia)occur in terrestrial habitats *** has been observed previously that their diversity decreases with increasing latitude and *** we look at dictyostelid diversity in the high latitude habitats of Northern *** were recovered from soil samples using traditional plating methods and then identified using morphological characters and molecular sequence(small subunit ribosomal RNA)*** total,nine species were recovered,including two new species,described herein as Dictyostelium barbibulus and Polysphondylium *** species diversity found here is discussed in relation to previous findings in the area as well as other high-latitude studies,and biogeographical patterns are *** total number of species found in Northern Sweden is lower than the numbers recorded for regions further south in Europe,a finding consistent with a latitudinal gradient of species *** findings highlight the benefit of using molecular data for accurate species identification in Dictyostelia and the need for a continued sampling effort to better understand their diversity and distribution,especially in high latitude habitats.

关键词： Cellular slime mold Dictyostelium Molecular identification New species Protist biogeography Sweden

HP0953-hypothetical virulence factor overexpresion and localization during Helicobacter pylori infection of gastric epithelium

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World Journal of Gastroenterology 2022年第29期28卷 3886-3902页

作者： Nancy K Arteaga-Resendiz Gerardo E Rodea Rosa María Ribas-Aparicio Alma l Olivares-Cervantes Juan Arturo Castelán-Vega Joséde Jesús Olivares-Trejo sandra Mendoza-Elizalde Edgar O lópez-Villegas Christian Colín Pamela Aguilar-Rodea Alfonso Reyes-lópez Marcela Salazar García Norma Velázquez-Guadarrama laboratorio de Investigación en Enfermedades Infecciosas Hospital Infantil de México Federico GómezMexico City 06720Mexico Posgrado en Biomedicina y Biotecnología Molecular Laboratorio de Producción y Control de BiológicosEscuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico laboratorio de Adquisición de Hierro Universidad Autónoma de la Ciudad MéxicoPosgrado Ciencias GenómicaMexico City 03100Mexico laboratorio Central de Microscopía Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico Centro de estudios económicos y sociales en salud Hospital Infantil de México Federico GómezMexico City 06720Mexico laboratorio de Investigación en Biología del Desarrollo y Teratogénesis Experimental Hospital Infantil de México Federico GómezMexico City 06720Mexico

BACKGROUND The high prevalence and persistence of Helicobacter pylori(H. pylori) infection, as well as the diversity of pathologies related to it, suggest that the virulence factors used by this microorganism are varied. Moreover, as its proteome contains 340hypothetical proteins, it is important to investigate them to completely understand the mechanisms of its virulence and survival. We have previously reported that the hypothetical protein HP0953 is overexpressed during the first hours of adhesion to inert surfaces, under stress conditions, suggesting its role in the environmental survival of this bacterium and perhaps as a virulence *** To investigate the expression and localization of HP0953 during adhesion to an inert surface and against gastric(AGS) *** Expression analysis was performed for HP0953 during H. pylori adhesion. HP0953 expression at 0,3, 12, 24, and 48 h was evaluated and compared using the Kruskal-Wallis equality-of-populations rank test. Recombinant protein was produced and used to obtain polyclonal antibodies for immunolocalization. Immunogold technique was performed on bacterial sections during adherence to inert surfaces and AGS cells, which was analyzed by transmission electron microscopy. HP0953 protein sequence was analyzed to predict the presence of a signal peptide and transmembrane helices, both provided by the ExPASy platform, and using the GlYCOPP platform for glycosylation sites. Different programs, via, I-TASSER, RaptorX, and HHalign-Kbest, were used to perform three-dimensional *** HP0953 exhibited its maximum expression at 12 h of infection in gastric epithelium *** technique revealed HP0953 localization in the cytoplasm and accumulation in some peripheral areas of the bacterial body, with greater expression when it is close to AGS *** analysis revealed the presence of a signal peptide that interacts with the transmembrane region and then allows the release of the protein

关键词： Hypothetical protein HP0953 Adherence Helicobacter pylori Glycocalyx Virulence factor Persistence

Assessment of conventional and air-jet wheel deflectors for drag reduction of the DrivAer model

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Advances in Aerodynamics 2021年第1期3卷 512-539页

作者： Kaloki l.Nabutola sandra K.S.Boetcher Department of Mechanical Engineering Embry-Riddle Aeronautical UniversityDaytona BeachFLUSA

Aerodynamic drag is a large resistance force to vehicle motion,particularly at highway *** wheel deflectors were designed to reduce the wheel drag and,consequently,the overall vehicle drag;however,they may actually be detrimental to vehicle aerodynamics in modern *** the present study,computational fluid dynamics simulations were conducted on the notchback DrivAer model-a simplified,yet realistic,open-source vehicle model that incorporates features of a modern passenger *** and air-jet wheel deflectors upstream of the front wheels were introduced to assess the effect of underbody-flow deflection on the vehicle *** wheel-deflector designs with varying heights were observed and compared to 45◦and 90◦air-jet wheel *** conventional wheel deflectors reduced wheel drag but resulted in an overall drag increase of up to 10%.For the cases studied,the 90◦air jet did not reduce the overall drag compared to the baseline case;the 45◦air jet presented drag benefits of up to 1.5%at 35 m/s and *** to conventional wheel deflectors,air-jet wheel deflectors have the potential to reduce vehicle drag to a greater extent and present the benefit of being turned off at lower speeds when flow deflection is undesirable,thus improving efficiency and reducing emissions.

关键词： Vehicle aerodynamics Wheel and wheelhouse aerodynamics Automotive Active flow control Passive flow control DrivAer

A geometric interpretation of the transition density of a symmetric lévy process

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Science China Mathematics 2012年第6期55卷 1099-1126页

作者： JACOB Niels KNOPOVA Victorya lANDWEHR sandra SCHIllING Renél. Department of Mathematics Swansea UniversitySingleton ParkSwansea SA28PPUK V.M.Glushkov Institute of Cybernetics NAS of Ukraine 03187KievUkraine Heinrich Heine University Düsseldorf German Diabetes Center at the Heinrich Heine University DüsseldorfLeibniz Center for Diabetes ResearchInstitute of Biometrics and EpidemiologyAuf'm Hennekamp 6540225 DüsseldorfGermany Institut für Mathematische Stochastik Technische Universität Dresden01062 DresdenGermany

We study for a class of symmetric levy processes with state space R^n the transition density pt（x） in terms of two one-parameter families of metrics, （dt）t〉o and （δt）t〉o. The first family of metrics describes the diagonal term pt （0）; it is induced by the characteristic exponent ψ of the levy process by dr（x, y） = √tψ（x - y）. The second and new family of metrics 6t relates to √tψ through the formula exp（-δ^2t（x,y））=F[e^-tψ/pt（0）]（x-y）,where Y denotes the Fourier transform. Thus we obtain the following ＂Gaussian＂ representation of the tran- sition density： pt（x） = pt（O）e^-δ^2t（x,0） where pt（O） corresponds to a volume term related to √tψ and where an ＂exponential＂ decay is governed by 5t2. This gives a complete and new geometric, intrinsic interpretation of pt（x）.

关键词： transition function estimates levy processes metric measure spaces heat kernel bounds in-finitely divisible distributions self-reciprocal distributions

Assessment of food supplementation and surveillance as techniques to reduce damage caused by black capuchin monkeys Sapajus nigritus to forest plantations

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Current Zoology 2014年第5期60卷 581-590页

作者： sandra Bos MIKICH laboratory of Ecology (laborat6rio de Ecologia) Embrapa Florestas Caixa Postal 319 CEP 83411-000 Colombo PR Brazil Black Capuchin Monkey Program (Programa Macaco-prego) National Fund for the Control of Forest Pests (Fundo Nacional de Controle de Pragas Florestais) Dieter liebsch Environmental Consulting (Dieter liebsch Consultoria Ambiental) Curitiba PR Brazil dieterliebsch@yahoo.com.br

Black capuchin monkeys Sapajus nigritus are among several mammalian species that damage forest plantations, pri- marily plantations of pine trees （Pinus spp.） in South Brazil. Management practices to reduce these damages include supplemen- tary food offerings and plantation surveillance. To assess the efficiency of these techniques, four treatments were evaluated： feeding （F, with supplementary bananas and maize）, surveillance （S, in situ, wherein men patrolled the plantations, deterring the monkeys）, feeding ＋ surveillance （FS） and control （no procedures）（C）. The efficiency assessment of each treatment involved the number of recorded primate sightings in the treatments with the presence of guards （S and FS） and a damage inventory of the outskirts of the experimental points immediately before and after the experiment. These data were complemented by a simulta- neous study of the availability of fruit, the primary item in the diet of this primate species, in the remnant native forest in the study area. Most sightings of S. nigritus occurred early in the morning, and in general, sightings were inversely proportional to the availability of native fruits. This trend was most evident in treatment FS, most likely due to the presence of food. Treatments F and FS exhibited higher percentages of damage, indicating that these are inefficient management techniques. Treatment S exhi- bited the lowest damage rate, but at a high cost, making this technique difficult to apply over large expanses. The development of other management techniques, such as environmental enrichment and the use of deterrents, is recommended to minimize the damage caused by capuchins in forest plantations [Current Zoology 60 （5）： 581-590, 2014].

关键词： Cebus Damage control Wildlife management Pinus Food provisioning

An overview of the phylogeny and diversity of eukaryotes

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植物分类学报 2008年第3期46卷 263-273页

作者： sandra l. BAlDAUF Department of Evolution Genomics and Systematics Evolutionary Biology Centre University of Uppsala Norbyvaigen 18 D Uppsala 75236 Sweden

Our understanding of eukaryote biology is dominated by the study of land plants, animals and fungi. However, these are only three isolated fragments of the full diversity of extant eukaryotes. The majority of eu-karyotes, in terms of major taxa and probably also sheer numbers of cells, consists of exclusively or predomi-nantly unicellular lineages. A surprising number of these lineages are poorly characterized. Nonetheless, they are fundamental to our understanding of eukaryote biology and the underlying forces that shaped it. This article consists of an overview of the current state of our understanding of the eukaryote tree. This includes the identity of the major groups of eukaryotes, some of their important, defining or simply interesting features and the pro-posed relationships of these groups to each other.

关键词：真核生物多样性系统演化真菌

Biocompatibility and electrochemical evaluation of ZrO_(2) thin films deposited by reactive magnetron sputtering on MgZnCa alloy

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Journal of Magnesium and Alloys 2021年第6期9卷 2019-2038页

作者： Benjamín Millán-Ramos Daniela Morquecho-Marín Phaedra Silva-Bermudez David Ramírez-Ortega Osmary Depablos-Rivera Julieta García-lópez Mariana Fernández-lizárraga JoséVictoria-Hernández Dietmar letzig Argelia Almaguer-Flores sandra E.Rodil Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Posgrado en Ciencia e Ingeniería de Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina RegenerativaInstituto Nacional de Rehabilitación Luis Guillermo IbarraCDMX 14389Mexico Posgrado en Ciencias Médicas Odontológicas y de la SaludUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico Instituto de Ciencias Aplicadas y Tecnologia Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Posgrado de Doctorado en Ciencias en Biomedicina y Biotecnología Molecular Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCDMX 11340Mexico Institute of Material and Process Design Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Magnesium Innovation Centre MagIC Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany laboratorio de Biointerfases Facultad de OdontologíaDivisión de Estudios de Posgrado e InvestigaciónUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico

Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be ***_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and *** this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was ***-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss *** results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the *** ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare ***,the ZrO_(2)coating prevents the adhesion and biofilm formation of ***.

关键词： Zirconium dioxide Magnetron sputtering Short-term degradation H_(2)evolution