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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

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

A comparative study of the morphometry of sperm head components in cattle, sheep, and pigs with a computer-assisted fluorescence method

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Asian Journal of Andrology 2016年第6期18卷 840-843页

作者： Jesus l Yaniz Sara Capistros sandra Vicente-Fiel Carlos O Hidalgo Pilar Santolaria TECNOGAM research group Environmental Sciences Institute (IUCA) Department of Animal Production and Food Sciences University of Zaragoza Huesca Spain Animal Genetics and Reproduction Area Regional Agrifood Research and Development Service (SERIDA) 33394 Deva Gijan Spain

The aim of this study was to compare the sperm nuclear and acrosomal morphometry of three species of domestic artiodactyls; cattle （Bos taurus）, sheep （Ovis aries）, and pigs （Sus scrofa）. Semen smears of twenty ejaculates from each species were fixed and labeled with a propidium iodide-Pisum sativum agglutinin （PI/PSA） combination. Digital images of the sperm nucleus, acrosome, and whole sperm head were captured and analyzed. The use of the PI/PSA combination and CASA-Morph fluorescence-based method allowed the capture, morphometric analysis, and differentiation of most sperm nuclei, acrosomes and whole heads, and the assessment of acrosomal integrity with a high precision in the three species studied. For the size of the head and nuclear area, the relationship between the three species may be summarized as bull 〉 ram 〉 boar. However, for the other morphometric parameters （length, width, and perimeter）, there were differences in the relationships between species for sperm nuclei and whole sperm heads. Bull sperm acrosomes were clearly smaller than those in the other species studied and covered a smaller proportion of the sperm head. The acrosomal morphology, small in the bull, large and broad in the sheep, and large, long, and with a pronounced equatorial segment curve in the boar, was species-characteristic. It was concluded that there are clear variations in the size and shape of the sperm head components between the three species studied, the acrosome being the structure showing the most variability, allowing a clear distinction of the spermatozoa of each species.

关键词： artiodactyls computer-assisted sperm morphometry analysis fluorescence microscopy image analysis sperm morphometry

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

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

Almost sure, l1-and l2-growth behavior of supercritical multi-type continuous state and continuous time branching processes with immigration

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Science China Mathematics 2020年第10期63卷 2089-2116页

作者： Mátyás Barczy sandra Palau Gyula Pap MTA-SZTE Analysis and Stochastics Research Group Bolyai InstituteUniversity of SzegedSzeged H-6720Hungary Department of Statistics and Probability Instituto de Investigaciones en Matemáticas Aplicadas y en SistemasUniversidad Nacional Autònoma de MéxicoCiudad de México 04510México Bolyai Institute University of SzegedSzeged H-6720Hungary

Under a first order moment condition on the immigration mechanism,we show that an appropriately scaled supercritical and irreducible multi-type continuous state and continuous time branching process with immigration(CBI process)converges almost *** an x log(x)moment condition on the branching mechanism does not hold,then the limit is *** this x log(x)moment condition holds,then we prove l1 convergence as *** projection of the limit on any left non-Perron eigenvector of the branching mean matrix is ***,in addition,a suitable extra power moment condition on the branching mechanism holds,then we provide the correct scaling for the projection of a CBI process on certain left non-Perron eigenvectors of the branching mean matrix in order to have almost sure and l1 ***,under a second order moment condition on the branching and immigration mechanisms,we prove l2 convergence of an appropriately scaled process and the above-mentioned projections as well.A representation of the limits is also provided under the same moment conditions.

关键词： multi-type continuous state and continuous time branching processes with immigration almost sure l1-and l2-growth behaviour

In search for novel strategies towards neuroprotection and neuroregeneration: is PPARα a promising therapeutic target?

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Neural Regeneration Research 2015年第9期10卷 1409-1412页

作者： sandra Moreno Maria Paola Cerù Department of Science-lIME University Roma Tre Department of life Health and Environmental Sciences University of L’AquilaCoppito (AQ) Italy

Peroxisome proliferator activated receptors： In the early 1990s, seminal work on rodent liver demonstrated that the hypolipidemic effect of xenobiotics, referred to as peroxisome proliferators, was mediated by a member of steroid hormone receptor superfamily, thus designated peroxisome proliferator-activated receptors （PPARs）（Issemann and Green, 1990; Dreyer et al., 1992）. The research field opened by this discovery led to the identification of three isotypes, namely PPARa （NR1C1）, PPAR[3/6 （NRIC2）, PPARy （NRIC3）, in a wide range of tissues. All these receptors act as ligand-activated transcription factors, binding lipid molecules with different, though overlapping, specificity.

关键词： PPAR a promising therapeutic target is PPAR

Comparison of different statistical approaches to evaluate morphometric sperm subpopulations in men

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Asian Journal of Andrology 2016年第6期18卷 819-823页

作者： Jesus l Yaniz sandra Vicente-Fiel Caries Soler Pilar Recreo Teresa Carretero Araceli Bono Jose M Berne Pilar Santolaria TECNOGAM research group Environmental Sciences Institute (IUCA) Department of Animal Production and Food Sciences Higher Polytechnic School University of Zaragoza Ctra. Cuarte S/N 22071 Huesca Spain Department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Valencia Spain R+D Department Proiser R+D Scientific Park University of Valencia 46980 Paterna Valencia Spain TECNOGAM research group Environmental Sciences Institute (IUCA) Departament of Human Anatomy and Histology Faculty of Health and Sport Sciences of Huesca Plaza Universidad 3 22002 Huesca Spain TECNOGAM research group Environmental Sciences Institute (IUCA) Hospital General San Jorge de Huesca Area de Urologla Av. Martfnez de Velasco 36 22004 Huesca Spain

This study was designed to characterize morphometric sperm subpopulations in normozoospermic men by using different statistical methods and examining their suitability to classify correctly different sperm nuclear morphologies present in human ejaculates. Ejaculates from 21 normozoospermic men were collected for the study. After semen collection and analysis, samples were prepared for morphometric determination. At least 200 spermatozoa per sample were assessed for sperm morphometry by computer-assisted sperm morphometry analysis （CASA-Morph） using fluorescence. Clustering and discriminant procedures were performed to identify sperm subpopulations from the morphometric data obtained. Clustering procedures resulted in the classification of spermatozoa into three morphometric subpopulations （large-round 30.4%, small-round 46.6%, and large-elongated 22.9%）. In the second analysis, using discriminant methods, the classification was made independently of size and shape. Three morphological categories according to nuclear size （small 〈10.90 μm^2, intermediate 10.91-13.07 μm^2, and large 〉13.07 μm^2） and four categories were defined on 400 canonical cells （100 × 4） from 10 men according to sperm nuclear shape （oval, pyriform, round, and elongated）. Thereafter, the resulting classification functions were used to categorize 4200 spermatozoa from 21 men. Differences in the class distribution were observed among men from both clustering and discriminant procedures. It was concluded that the combination of CASA-Morph fluorescence-based technology with multivariate cluster or discriminant analyses provides new information on the description of different morphometric sperm subpopulations in normal individuals, and that important variations in the distribution of morphometric sperm subpopulations may exist between men, with possible functional implications.

关键词： computer-assisted sperm morphometry analysis man sperm subpopulations