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Semen analysis： a new manual and its application to the understanding of semen and its pathology

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Asian Journal of Andrology 2010年第1期12卷 11-13页

作者： anne M. Jequier PIVET Medical Centre Leederville Western Australia 6007 Australia

This article reviews the latest edition of the World Health Organization＇s manual on seme instructional guide. The methodology used in the assessment of the usual variables in semen many of the less common, but very valuable, sperm function tests. Seminal fluid preparatio such as in vitro fertilization and intrauterine insemination are also outlined in the manual. useful techniques for the assessment of seminal fluid. It will be a very useful manual for an analyses of seminal fluid.

关键词： laboratory practice male infertility semen analysis

The Polycomb Complex PRC1:Composition and Function in Plants

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Journal of Genetics and Genomics 2013年第5期40卷 231-238页

作者： anne Molitor Wen-Hui Shen Institut de Biologie Moléculaire des Plantes du CNRS Université de Strasbourg12 rue du Général Zimmer67084 StrasbourgFrance Institut J.-P.Bourgin UMR1318 INRA-AgroParisTechINRAroute de Saint Cyr78026 VersaillesFrance

Polycomb group（PcG） proteins are crucial epigenetic regulators conferring transcriptional memory to cell *** assemble into multi-protein complexes,e.g.,Polycomb Repressive Complex 1 and 2（PRC1,PRC2）,which are thought to act in a sequential manner to stably maintain gene ***2 induces histone H3 lysine 27（H3K27） trimethylation（H3K27me3）,which is subsequently read by PRCl that further catalyzes H2A monoubiquitination（H2Aub1）,creating a transcriptional silent chromatin ***2 components are conserved in plants and have been extensively characterized in *** contrast,PRCl composition and function are more diverged between animals and *** more recently,PRC1 existence in plants has been *** we review the aspects of plant specific and conserved PRC1 and highlight critical roles of PRC1 components in seed embryonic trait determinacy,shoot stem cell fate determinacy,and flower development in Arabidopsis.

关键词： Epigenetics Chromatin Histone modifications Polycomb PRC1 Arabidopsis development

Circadian regulation of Limulus visual functions:A role for octopamine and cAMP

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Current Zoology 2010年第5期56卷 518-536页

作者： Jasbir S.DALAL Barbara-anne BATTELLE Whitney Laboratory for Marine Bioscience and the Departments of Neuroscience and Biology University of Florida Department of Internal Medicine and Division of Human Nutrition and Metabolic Diseases University of Texas Southwestern Medical Center

The purpose of this contribution is to review our current understanding of the source and biochemistry of the circadian efferent input to the eyes of the American horseshoe crab Limuluspolyphemus and the impact of this input on the structure, physiology and biochemistry of Limulus eyes. Special emphasis is given to the role of the biogenic amine octopamine and bio- chemical cascades it activates in the eyes. In addition to reviewing published data, we present new data showing that octopamine elevates cAMP levels in Limulus lateral eyes, and we partially characterize the pharmacology of the receptors involved in this response. We also present new data showing that octopamine regulates gene expression in Limulus lateral eyes by activating a cAMP cascade

关键词： Horseshoe crab Circadian rhythms Oetopamine Photoreceptors Substance P Arrestin

Purification of solar cell silicon materials through filtration

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Rare Metals 2006年第Z1期25卷 180-185页

作者： CIFTJA Arjan ENGH Thorvald Abel KVITHYLD anne Department of Materials Science and Engineering Norwegian University of Science and Technology Trondheim N-7491 Norway

Silicon is the material most commonly used in the manufacturing of photovoltaic (PV) cells. In the current study, laboratory experiments of purification of solar cell silicon materials through filtration are carried out. Inclusion removal from silicon was investigated. The purpose is to achieve clean silicon materials for solar cells. Silicon samples and filter samples were analyzed using microscope observation, EPMA, and X-ray detection. Silicon nitride (Si3N4) and silicon carbide (SiC) particles are the main non-metallic inclusions present in top-cut silicon scrap. Almost all inclusions larger than 10 μm can be removed from silicon by the porous foam filter. In mass fraction, more than 90% inclusions are removed. Si3N4 particles are mainly removed on the top surface of the filter, and SiC particles are mainly removed by entering the pores and attaching to the filter material. SiC inclusions are not only simply attached on the surface of the filter material, but are found also inside the filter material. There are SiC bridges near the filter materials. These bridges may fill the spaces between filter material, and this will further retard inclusions passing through the filter. Three-dimensional turbulent fluid flow and inclusion motion in the filter was calculated. Both experimental observation and fluid flow simulation indicate that most of the inclusions are entrapped at the upper part of the filter.

关键词： solar cell silicon inclusions filtration nitrides carbides fluid flow

Comparisons of corrosion behaviour for X65 and low Cr steels in high pressure CO2-saturated brine

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Journal of Materials Science & Technology 2020年第6期41卷 21-32页

作者： Yong Hua Sikiru Mohammed Richard Barker anne Neville Institute of Functional Surfaces School of Mechanical Engineering University of Leeds Leeds LS2 9JT United Kingdom

Appropriate materials for injection pipelines and tubing for carbon dioxide geologic storage is fundamental to ensure asset integrity and save *** paper evaluates the corrosion behaviour of X65,1Cr,3Cr and 5Cr,which have the potential to be injection pipeline/tubing *** influence of steel Cr content on the general and localised corrosion behaviour was investigated at time periods from 6 to 192 h at 60℃and 100 *** evolution,morphology and chemistry of corrosion products on the surface of each material were evaluated using a combination of scanning electron microscopy,energy dispersive X-ray spectroscopy and X-ray diffraction and related to their overall corrosion *** indicate that prior to the formation of protective films on the steel surfaces,the resistance of the materials to corrosion increase with increasing Cr content(Corrosion resistance:X651Cr>3Cr>5Cr).In terms of the corrosion products on X65,both inner amorphous and outer crystalline corrosion layers consist of *** the Cr-containing steels,the outer layer also comprises FeCO3,but the inner layer is enriched with Cr,and is predominantly amorphous Cr(OH)*** extent of localised corrosion(determined using surface profilometry)is noticeably less for X65 compared to the Cr-containing *** paper raises questions about the benefits that low Cr steels offer towards extending component design life compared to carbon steel under the test conditions considered here.

关键词： Carbon dioxide Corrosion X65 Low-Cr steels Iron carbonate Chromium hydroxide

Zygotic chromosomal structural aberrations after paternal drug treatment

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Asian Journal of Andrology 2015年第6期17卷 939-941页

作者： anne Marie Downey Bernard Robaire Departments of Pharmacology and Therapeuticsand of Obstetrics and Gynecology McGill UniversityMontreal Quebec Canada.

In recent years, the field of male-mediated reproductive toxicology has received growing attention. It is now well-established that many drugs, chemicals, and environmental factors can harm male germ cells by inducing DNA damage. Male germ cells have extensive repair mechanisms that allow detection and repair of damaged DNA during the early phases of spermatogenesis. However, during the later phase of spermiogenesis, when the haploid spermatids undergo chromatin condensation and become transcriptionally quiescent, their ability to repair damaged DNA is lost. It is also thought that the highly compacted chromatin of the sperm can protect DNA against damage. Therefore, it is expected that late spermatids will be most susceptible to DNA damaging agents. Unrepaired or misrepaired damage in the germ cells leads to the generation of spermatozoa with DNA damage that can be transmitted to the next generation. Fortunately, the maternal DNA repair machinery is capable of recognizing and repairing, at least to some degree, damaged paternal DNA after fertilization in the zygote. Therefore, the efficiency of the maternal repair machinery will greatly influence the risk of transmitting paternal DNA damage to offspring.

关键词： Zygotic chromosomal treatment

Classical and non-classical MHC I molecule manipulation by human cytomegalovirus： so many targets--but how many arrows in the quiver？

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Cellular & Molecular Immunology 2015年第2期12卷 139-153页

作者： anne Halenius Carolin Gerke Hartmut Hengel Institute of Virology University Medical Center Albert-Ludwig-University Freiburg Freiburg Germany

Major mechanisms for the recognition of pathogens by immune cells have evolved to employ classical and non-classical major histocompatibility complex class I （MHC I） molecules. Classical MHC I molecules present antigenic peptide ligands on infected cells to CD8＋ T cells, whereas a key function for non-classical MHC I molecules is to mediate inhibitory or activating stimuli in natural killer （NK） cells. The structural diversity of MHC I puts immense pressure on persisting viruses, including cytomegaloviruses. The very large coding capacity of the human cytomegalovirus allows it to express a whole arsenal of immunoevasive factors assigned to individual MHC class I targets. This review summarizes achievements from more than two decades of intense research on how human cytomegalovirus manipulates MHC I molecules and escapes elimination by the immune system.

关键词： antigen presentation CD8+ T cells NK cells human cytomegalovirus immune evasion KIR

Seed wasp invasions promoted by unregulated seed trade affect vegetal and animal biodiversity

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Integrative Zoology 2012年第3期7卷 228-246页

作者： Marie-anne AUGER-ROZENBERG Alain ROQUES French National Institute for Agricultural Research(INRA) Forest Ecology(UR633)OrleansFrance

Cone and seed insects are considered the most important predators of tree seeds during the pre-dispersal phase of *** them,exotic seed chalcids in the genus Megastigmus invaded Europe as a result of the rapidly-increasing and mostly unregulated seed trade for afforestation and ornamental *** their economic impact in seed orchards,until recently,little attention was paid to the ecological impact of these *** the present study,selected case studies of alien Megastigmus *** considered to assess their specific impact on the potential of natural regeneration of native woody plants and on the native entomofauna competing for seed *** re-analyzed data from former studies that did not focus on these ecological interactions and,here,present previously unpublished *** of Douglas-fir,true cedars,true firs and wild roses were sampled all over Europe,and the relative importance of the native and invasive chalcid species was assessed as well as their specific impact on seed *** most cases,the recent arrival of alien chalcids resulted in a significant decrease in the regeneration potential of the host *** the absence of competitors,alien chalcids occupied the entire seed niche in Douglas-fir,but their impact tended to decrease after the arrival of invasive seed *** firs,alien chalcids tended to displace the native chalcids,but not in wild roses and cedars,where their damage was *** biological traits that might explain invasive success of alien chalcids are ***,no general invasive patterns seem to exist.

关键词： ecological impact invasion Megastigmus seed trade

MYB Transcription Factors as Regulators of Phenylpropanoid Metabolism in Plants

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Molecular Plant 2015年第5期8卷 689-708页

作者： Jingying Liu anne Osbourm Pengda Ma College of Life Sciences Northwest A&F University Yangling 712100 China Department of Metabolic Biology John Innes Centre Norwich NR4 7UH UK

Phenylpropanoid-derived compounds represent a diverse family of secondary metabolites that originate from phenylalanine. These compounds have roles in plant growth and development, and in defense against biotic and abiotic stress. Many of these compounds are also beneficial to human health and welfare. V-myb myeloblastosis viral oncogene homolog （MYB） proteins belong to a large family of transcription factors and are key regulators of the synthesis of phenylpropanoid-derived compounds. This review summarizes the current understanding of MYB proteins and their roles in the regulation of phenylpropanoid metabolism in plants.

关键词： MYB monolignol flavonoid phenolic acid stilbene