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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

Thermal desorption of mercury from lignite in a high-temperature furnace and in power plant mills

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International Journal of Coal Science & Technology 2022年第5期9卷 150-159页

作者： anne-Christin Kropp Kathrin Gebauer Michael Beckmann Institute of Process Engineering and Environmental Technology Faculty of Mechanical Science and EngineeringTU Dresden01062 DresdenGermany

In this article,the binding forms of two lignite samples are determined by thermal desorption using a high-temperature *** mercury compound,such as HgCl2,has a specifc binding strength whose decomposition requires a certain thermal ***,the release of mercury from pure substances and lignite samples was analyzed in a high-temperature *** released mercury is determined with a Mercury Vapor *** obtained characteristic temperature range and peak of the mercury release were compared between lignite samples and mercury pure *** the lignite samples investigated,the binding form of mercury was then identifed as Humic *** organic compounds vaporize at lower *** half of the mercury bound in the lignite was already released at 350℃.Furthermore,the question arises whether mercury is already released during the grinding-drying process in the coal mill of a power *** two power plants,lignite samples were taken simultaneously at the feeder before entering the coal mill and at the dust line *** samples were analyzed for mercury *** results show that up to one third of the mercury was already released in the coal *** vaporized mercury enters the combustion chamber detached from the *** stated analysis methods and the results presented in this article contribute to the understanding of the mercury binding forms in *** also shows the potential of thermal coal pretreatment as a favorable alternative mercury separation technology to others such as activated carbon dosing.

关键词： Mercury binding forms Thermal desorption Mercury release Coal mill Coal pretreatment

Soil microbial response to waste potassium silicate drilling fluid

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Journal of Environmental Sciences 2015年第3期27卷 189-198页

作者： Linjun Yao M.anne Naeth Allen Jobson Department of Renewable Resources University of Alberta School of Land Science and Technology China University of Geosciences (Beijing)

Potassium silicate drilling fluids （PSDF） are a waste product of the oil and gas industry with potential for use in land reclamation. Few studies have examined the influence of PSDF on abundance and composition of soil bacteria and fungi. Soils from three representative locations for PSDF application in Alberta, Canada, with clay loam, loam and sand textures were studied with applications of unused, used once and used twice PSDF. For all three soils, applying ≥40 m^3/ha of used PSDF significantly affected the existing soil microbial flora. No microbiota was detected in unused PSDF without soil. Adding used PSDF to soil significantly increased total fungal and aerobic bacterial colony forming units in dilution plate counts, and anaerobic denitrifying bacteria numbers in serial growth experiments. Used PSDF altered bacterial and fungal colony forming unit ratios of all three soils.

关键词： Drilling waste Potassium silicate drilling fluid Soil Microbiota

Silicone rubbers for dielectric elastomers with improved dielectric and mechanical properties as a result of substituting silica with titanium dioxide

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International Journal of Smart and Nano Materials 2015年第4期6卷 268-289页

作者： Liyun Yu anne Ladegaard Skov The Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of Denmark2800 Kgs.LyngbyDenmark

One prominent method of modifying the properties of dielectric elastomers(DEs)is by adding suitable metal oxide ***,almost all commercially available sili-cone elastomers are already heavily filled with silica to reinforce the otherwise rather weak silicone network and the resulting metal oxide filled elastomer may contain too much *** therefore explore the replacement of silica with titanium dioxide to ensure a relatively low concentration of *** silicone rubber(LSR)has relatively low viscosity,which is favorable for loading inorganic *** the present study,four commercial LSRs with varying loadings of silica and one benchmark room-temperature vulcanizable rubber(RTV)were *** resulting elastomers were evaluated with respect to their dielectric permittivity,tear and tensile strengths,electrical breakdown,thermal stability and dynamic *** silicone elasto-mers with high loadings of nano-sized titanium dioxide(TiO_(2))particles were also *** best overall performing formulation had 35 wt.%TiO_(2) nanoparticles in the POWERSIL®XLR LSR,where the excellent ensemble of relative dielectric permittivity of 4.9 at 0.1 Hz,breakdown strength of 160 V µm^(−1),tear strength of 5.3 MPa,elongation at break of 190%,a Young’s modulus of 0.85 MPa and a 10% strain response(simple tension)in a 50 Vμm^(−1) electric field was obtained.

关键词： silicone rubber titanium dioxide dielectric permittivity mechanical properties electrical breakdown

Analytical solution for a strong free-surface water vortex describing flow in a full-scale gravitational vortex hydropower system

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Water Science and Engineering 2021年第1期14卷 72-79页

作者： Vladimir Joel Alzamora Guzman Julie anne Glasscock Energy Research Group Kadagaya Research Centre for Appropriate TechnologyJunin 12866Peru

Strong free-surface water vortices are found throughout industrial hydraulic systems used for water treatment,flow regulation,and energy *** models using the volumetric flow rate as a model input have generally been semi-empirical,and have tended to have some limitations in terms of the design of practical hydropower *** this study,an analytical model of a strong free-surface water vortex was *** model only requires the water head and geometric parameters as its inputs and calculates the maximum volumetric flow rate,aircore diameter,and rotational *** experimental depthedischarge data from a full-scale gravitational vortex hydropower system,unavailable in the relevant literature,were obtained,and the simulated results showed excellent agreement with the experimental *** data could be used to verify similar models using laboratory-scale physical models in order to investigate the scaling *** contrast to previous models,this model does not assume a constant average velocity across the vortex radius and allows precise calculation of the resultant velocity ***,this model presents advantages in turbine design for energy generation systems.

关键词： Gravitational vortex Velocity measurements Scalability Analytical model Microhydropower

Optimal machining conditions for turning Ti-6Al-4V using response surface methodology

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Advances in Manufacturing 2013年第4期1卷 329-339页

作者： Satyanarayana Kosaraju Venu Gopal anne Department of Mechanical Engineering National Institute of TechnologyWarangal

Machining titanium is one of ever-increasing magnitude problems due to its characteristics such as low thermal conductivity, modulus of elasticity and work hardening. The efficient titanium alloy machining involves a proper selection of process parameters to minimize the tangential force （Fz） and surface roughness （Ra）. In the present work, the performance of PVD/TiA1N coated carbide inserts was investigated using response surface methodology （RSM） for turning Ti-6A1-4V. The effects of process parameters such as speed （v）, feed （/＇）, depth of cut （d） and back rake angle （Ty） on Fz and Ra were investi- gated. The experimental plan used for four factors and three levels was designed based on face centered, central composite design （CCD）. The experimental results indi- cated that Fz increased with the increase in d, f and decreased with the increase in v and yy, whereas Ra decreased with the increase in v and 7y, and increased with d and v. The goodness of fit of the regression equations and model fits （R2） for Fz and Ra were found to be 0.968 and 0.970, which demonstrated that it was an effective model. A confirmation test was also conducted in order to verify the correctness of the model.

关键词： Ti-6Al-4V - Response surfacemethodology ~ Cutting force ~ Surface roughness