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Putting things in place for fertilization： discovering roles for importin proteins in cell fate and spermatogenesis

Asian Journal of Andrology 2015年第4期17卷 537-544页

作者： Kate L Loveland Andrew T Major Romaly Butler Julia C Young david a jan Yoichi Miyamoto Department of Biochemistry and Molecular Biology Monash University Clayton VIC Australia Department of Anatomy and Developmental Biology Monash UniversityClayton VlC Australia Hudson Institute of Medical Research Monash Medical Centre Clayton VlC Australia School of Clinical Sciences Monash University ClaytonVlC Laboratory of Nuclear Transport Dynamics National Institutes of Biomedical Innovation Health and Nutrition Osaka Japan.

Importin proteins were originally characterized for their central role in protein transport through the nuclear pores, the only intracellular entry to the nucleus. This vital function must be tightly regulated to control access by transcription factors and other nuclear proteins to genomic DNA, to achieve appropriate modulation of cellular behaviors affecting cell fate. Importin-mediated nucleocytoplasmic transport relies on their specific recognition of cargoes, with each importin binding to distinct and overlapping protein subsets. Knowledge of importin function has expanded substantially in regard to three key developmental systems： embryonic stem cells, muscle cells and the germ line. In the decade since the potential for regulated nucleocytoplasmic transport to contribute to spermatogenesis was proposed, we and others have shown that the importins that ferry transcription factors into the nucleus perform additional roles, which control cell fate. This review presents key findings from studies of mammalian spermatogenesis that reveal potential new pathways by which male fertility and infertility arise. These studies of germline genesis illuminate new ways in which importin proteins govern cellular differentiation, includ ng v a d rect ng proteins to d st nct ntrace ular compartments and by determining cellular stress responses.

关键词： cell fate cell stress importin karyopherin nucleocytoplasmic transport spermatid spermatocyte spermatogenesis

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Pneumatic Measurements Downstream of a Radial Turbine Nozzle Cascade

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Journal of Thermal Science 2010年第1期19卷 42-46页

作者： Martin LUXA Rudolf DVORAK david SIMURDA jan VIMMR Department of Fluid Dynamics Institute of Thermomechanicsv.v.i.Academy of Science of the Czech RepublicPragueCzech Republic Department of Mechanics University of West Bohemia in PilsenPlzeňCzech Republic

This paper deals mainly with pneumatic measurements on a radial turbine nozzle cascade. The fill radial cascade guarantees the exit flow field periodicity downstream of it. A special traversing mechanism with a five - hole conical probe moving along a circular path behind the cascade was used for flow field investigation in this type of cascade with very low aspect ratio. The analyses of results of 2D and 3D pneumatic measurements including loss coefficient values are presented.

关键词： radial turbine cascade aspect ratio pneumatic measurement loss coefficient

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Hybrid LES/RANS Simulations of Compressible Flow in a Linear Cascade of Flat Blade Profiles

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Journal of Thermal Science 2024年第5期33卷 1839-1850页

作者： Jaromír PRIHODA Petr STRAKA david SIMURDA Petr SIDLOF jan LEPICOVSKY Institute of Thermomechanics of the Czech Academy of Sciences Dolejskova 1402/518200 Prague 5Czech Republic Aerospace Research and Test Centre Beranovych 13019905 PragueCzech Republic Technical University of Liberec Faculty of MechatronicsStudentska 246117 Liberec 1Czech Republic

The paper reports on 3D numerical simulations of unsteady compressible airflow in a blade cascade consisting of flat profiles using a hybrid LES/RANS approach including a transition *** a first step towards simulation of blade flutter in turbomachinery,various incidence angle offsets of the middle blade were *** simulations were run for the flow regime characterized by outlet isentropic Mach number M_(is)=0.5and zero *** results of the LES/RANS simulations(pressure and Mach number distributions)were compared to a baseline RANS model,and to experimental data measured in a high-speed wind *** numerical results show that both methods overpredict flow separation taking place at the leading *** this regard,the hybrid LES/RANS method does not provide superior results compared to the traditional RANS ***,the LES/RANS results also capture vortex shedding from the blunt trailing *** frequency of the trailing edge vortex shedding in CFD simulations matches perfectly the spectral peak recorded during wind tunnel measurements.

关键词： numerical simulation blade cascade hybrid LES/RANS

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Alternative feedstock for the production of activated carbon with ZnCl_(2):Forestry residue biomass and waste wood

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Carbon Resources Conversion 2022年第4期5卷 299-309页

作者： Dominik Bosch jan OBack david Gurtner Sara Giberti Angela Hofmann Anke Bockreis Josef Ressel Centre for Production of Activated Carbon from Municipal Residues Department of EnvironmentalProcess and Energy EngineeringMCI–The Entrepreneurial SchoolUniversitaetsstrasse 156020 InnsbruckAustria Unit of Environmental Engineering Department for InfrastructureUniversity of InnsbruckTechnikerstrasse 136020 InnsbruckAustria Department of Environmental Process and Energy EngineeringMCI–The Entrepreneurial SchoolUniversitaetsstrasse 156020 InnsbruckAustria Institute for Chemical and Energy Engineering BOKU-University of Natural Resources and Life ScienceGregor-Mendel-Strasse 331160 ViennaAustria Department of Civil ChemicalEnvironmentaland Materials EngineeringUniversit`a di BolognaVia Zamboni 3340126 BolognaItaly

In order to substitute fossil resources in activated carbon(AC)production,recent efforts have focused on the utilization of renewable raw *** with important wood industries offer two potentially underestimated resource types:forestry residue biomass(FRB)and waste wood(WW).Although these materials are widely available(approx.130 mio.m3a-1 FRB,approx.50 ***^(-1) WW in the EU),they are mostly valorised through energy production,as they are high in ashes and may be contaminated with organics and heavy *** this study,both FRB and WW were treated via one-step pyrolysis for AC ***_(2) was applied as activating agent at pyrolysis temperatures varying from 400 to 600℃ and residence times between 1 and 3 ***,76 samples were prepared and characterized thoroughly via elemental analysis,N_(2)/CO_(2) ad/-desorption,thermogravimetric analysis(TGA),scanning electron microscopy(SEM),and infrared spectroscopy(FTIR).The produced carbons showed specific surface areas of up to 1430 m2g􀀀1 and a pore size distribution with a micropore share of up to 80%.The presence of oxygen-containing functional groups was confirmed via *** feedstock contamination can be mitigated,as minerals and heavy metals could be leached out(up to-99.15%)by an additional wash step and organic contamination undergoes thermal cracking during *** presented study could be a next step in upcycling considerable waste streams from the wood sector through localised and non-fossil-based AC production.

关键词： Sustainable resources Waste wood Forestry residue Activated carbon Chemical activation Pyrolysis Porosity Functionalized surface

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PEPT study of particle motion for different riser exit geometries

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Particuology 2010年第6期8卷 623-630页

作者： Chian Wen Chan Anke Brems Shiva Mahmoudi jan Baeyens Jonathan Seville david Parker Thomas Leadbeater Joseph Gargiuli University of Warwick School of EngineeringCoventryCV4 7 ALUK Katholieke Universiteit Leuven Department of Chemical Engineeringde Croylaan463001LeuvenBelgium University of Birmingham School of Physics and AstronomyBirminghamB22 T15UK

Laboratory and industrial risers are equipped with exits of many different layouts, and numerous publications discuss the influence of riser exit geometry on local and overall solids hydrodynamics in the riser. The present paper reviews literature findings--mostly based upon indirect experimental techniques and often somewhat contradictory, Direct measurement of particle velocity and particle occupancy near and in the riser exit provide a better indication of the effect of riser exit geometry. Positron Emission Particle Tracking （PEPT） was used in this work for the first time to investigate the exit region of the riser, An abrupt or sharp exit causes particles to be knocked out of the gas flow, so forming a recirculation or reflux region in the upper part of the riser. This is much less pronounced with a curved or gradual exit.

关键词： CFB Riser Exit geometries Positron Emission Particle Tracking

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Beyond direct neighbourhood effects: higher-order interactions improve modelling and predicting tree survival and growth

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National Science Review 2021年第5期8卷 38-47页

作者： Yuanzhi Li Margaret M.Mayfield Bin Wang Junli Xiao Kamil Kral david janik jan Holik Chengjin Chu Department of Ecology State Key Laboratory of BiocontrolSchool of Life SciencesSun Yat-sen University Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain Guangxi Institute of BotanyGuangxi Zhuang Autonomous Region and Chinese Academy of Sciences Department of Silviculture Faculty of Forestry and Wood TechnologyMendel University in Brno School of Biological Sciences The University of Queensland Department of Forest Ecology Silva Tarouca Research Institute

It is known that biotic interactions are the key to species coexistence and maintenance of species *** studies focus overwhelmingly on pairwise interactions between organisms, ignoring complex higher-order interactions(HOIs). In this study, we present a novel method of calculating individual-level HOIs for trees, and use this method to test the importance of size-and distance-dependent individual-level HOIs to tree performance in a 25-ha temperate forest dynamic plot. We found that full HOI-inclusive models improved our ability to model and predict the survival and growth of trees, providing empirical evidence that HOIs strongly influence tree performance in this temperate forest. Specifically, assessed HOIs mitigate the competitive direct effects of neighbours on survival and growth of focal trees. Our study lays a foundation for future investigations of the prevalence and relative importance of HOIs in global forests and their impact on species diversity.

关键词： pairwise interactions indirect interactions density-dependent size- and distance-dependent Zofin Forest Dynamic Plot

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Molecular Dynamics Simulations of Nanoparticle Interactions with a Planar Wall:Does Shape Matter?

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Communications in Computational Physics 2013年第3期13卷 900-915页

作者： Andreas Fuchs david Kauzlaric Andreas Greiner Sauro Succi jan.G.Korvink Laboratory for Simulation Department of Microsystems Engineering(IMTEK)University of FreiburgGeorges-Kohler-Allee 10379110 FreiburgGermany School of Soft Matter Research Freiburg Institute for Advanced StudiesUniversity of FreiburgAlbertstr.1979104 FreiburgGermany Istituto Applicazioni Calcolo CNRvia dei Taurini 900185RomaItaly

We investigate the hydrodynamic interactions of spherical colloidal nano particles and nano tetrahedra near a planar wall by means of molecular dynamics(MD)simulations of rigid particles within an all-atom *** both spherical and nano-tetrahedral particles,we find that the parallel and perpendicular components of the local diffusion coefficient and viscosity,show good agreement with hydrodynamic theory of Fax´en and *** provides further evidence that low perturbations from sphericality of a nanoparticle’s shape has little influence on its local diffusive behaviour,and that for this particular case,the continuum theory fluid dynamics is valid even down to molecular scales.

关键词： Molecular dynamics simulation nanoparticle hydrodynamic interaction

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Bacteriocinogeny in experimental pigs treated with indomethacin and Escherichia coli Nissle

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World Journal of Gastroenterology 2011年第5期17卷 609-617页

作者： jan Bures david Smajs Jaroslav Kvetina Miroslav Frstl jan Smarda Darina Kohoutova Martin Kunes Jiri Cyrany Ilja Tacheci Stanislav Rejchrt Jirina Lesna Viktor Vorisek Marcela Kopacova 2nd Department of Medicine Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital500 05 Hradec KraloveCzech Republic Department of Biology Masaryk UniversityFaculty of Medicine625 00 BrnoCzech Republic Institute of Experimental Biopharmaceutics Joint Research Centre of Czech Academy of Sciences and PRO.MED.CS Praha a.s.500 02 Hradec KraloveCzech Republic Institute of Clinical Microbiology Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital500 05 Hradec KraloveCzech Republic Institute of Clinical Biochemistry and Diagnostics Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital500 05 Hradec KraloveCzech Republic

AIM： To evaluate bacteriocinogeny in short-term highdose indomethacin administration with or without probiotic Escherichia coli Nissle 1917 （EcN） in experimental ***： Twenty-four pigs entered the study： Group A （controls）, Group B （probiotics alone）, Group C （indomethacin alone） and Group D （probiotics and indomethacin）. EcN （3.5 × 10^10 bacteria/d for 14 d） and/or indomethacin （15 mg/kg per day for 10 d） were administrated orally. Anal smears before and smears from the small and large intestine were taken from all animals. Bacteriocin production was determined with 6 different indicator strains; all strains were polymerase chain reaction tested for the presence of 29 individual bacteriocinencoding determinants. RESULTS： The general microbiota profile was rather uniform in all animals but there was a broad diversity in coliform bacteria （parallel genotypes A, B1, B2 and D found）. In total, 637 bacterial strains were tested, mostly Escherichia coli （E. coli. There was a higher incidence of non-E：, coli strains among samples taken from the jejunum and ileum compared to that of the colon and rectum indicating predominance of E. coil strains in the large intestine. Bacteriocinogeny was found in 24/77 （31%） before and in 155/560 （28%） isolated bacteria at the end of the study. Altogether, 13 individual bacteriocin types （out of 29 tested） were identified among investigated strains. Incidence of four E. coli genotypes was equally distributed in all groups of E. coil strains, with majority of genotype A （ranging from 81% to 88%）. The following types of bacteriocins were most commonly revealed： colicins Ia/Ib （44%）, microcin V （18%）, colicin E1 （16%） and microcin H47 （6%）. There was a difference in bacteriocinogeny between control group A （52/149, 35%） and groups with treatment at the end of the study： B： 31/122 （25%, P = 0.120）; C： 43/155 （28%, P = 0.222）; D： 29/134 （22%, P = 0.020）. There was a significantly lower prevalence of colicin Ib, microcins H47 and V （pr

关键词： Bacteriocinogeny Escherichia coli Nissle1917 Experimental pigs Indomethacin

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Apochromatic X-ray focusing

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Light(Science & Applications) 2023年第7期12卷 1301-1308页

作者： Umut T.Sanli Griin Rodgers Marie-Christine Zdoraol Peng Qio jan Garrevoet Ken Vidar Falch Bert Muller Christian david Joan Vila-Comamala Paul Scherrer Institute Laboratory for X-ray Nanoscience and TechnologiesForschungsstrasse 1115232 ViligenSwitzerland Biomaterials Science Center Department of Biomedical EngineeringUniversity of BaselHegenheimermattweg 167 B4123 AllschwilSwitzerland Deutsches Elektronen-Synchrotron DESY Notkestr.8522607 HamburgGermany

Achromatic doublets are combinations of two individual lenses designed to focus different wavelengths of light in the same *** optics are improved versions of the achromatic schemes which extend the wavelength range *** achromatic and apochromatic optics are well-established for visible ***,X-ray achromatic lenses did not exist until very recently,and X-ray apochromatic lenses have never been experimentally ***,we create an X-ray apochromatic lens system using an appropriate combination of a Fresnel zone plate and a diverging compound refractive lens with a tuned separation *** energy-dependent performance of this apochromat was characterized at photon energies between 6.5 and 13.0 keV by ptychographic reconstruction of the focal spot and scanning transmission X-ray microscopy of a resolution test *** apochromat delivered a reconstructed focal spot size of 940×740 nm^(2).The apochromatic combination shows a four-fold improvement in the chromatic aberration correction range compared to an achromatic doublet ***,apochromatic X-ray optics have the potential to increase the focal spot intensity for a wide variety of X-ray applications.

关键词： chromatic optics correction

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Functional diversity and trait composition of butterfly and bird communities in farmlands of Central Romania

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Ecosystem Health and Sustainability 2015年第10期1卷 17-25页

作者： jan Hanspach Jacqueline Loos Ine Dorresteijn Henrik vonWehrden Cosmin Ioan Moga Alin david Leuphana University Faculty of SustainabilityScharnhorststrasse 121335 LueneburgGermany Leuphana University Center for MethodsScharnhorststrasse 121335 LueneburgGermany Educational-Ecological Association Ecotransilvania Tabacarilor 11A545400 SighisoaraRomania Department of Taxonomy and Ecology Babes-Bolyai UniversityClinicilor Strada 5-7400006 Cluj-NapocaRomania

Cultural landscapes all over the world harbor species communities that are taxonomically and functionally *** Eastern Europe,but also in many other regions of the world,the conservation of this farmland biodiversity is threatened by land use intensification and *** order to counteract the negative effects of land use change in such landscapes,a thorough understanding of the functional relationships between species and their environment is *** this study,we investigated the relationship of functional traits of butterfly and bird communities and environmental conditions in 120 sites in traditional farmlands of southern Transylvania,***,we compared taxonomic diversity(i.e.,Shannon diversity)with functional diversity(i.e.,functional dispersion),and second,we linked species traits to environmental variables by performing RLQ *** traits indicating reproduction,movement,and feeding behavior related with environmental variables describing heterogeneity,amount of woody vegetation,and topography at three different spatial *** found positive relationships between taxonomic and functional diversity,as well as strong linkages between species traits and environmental conditions for both ***,butterfly composition was most strongly influenced by land use type and life-history *** composition was most strongly related to the amount of woody vegetation and nesting and foraging *** conclude that maintaining the typical features of traditional farming landscapes,especially a small-scale heterogeneity in arable land and gradients of woody vegetation cover,would be desirable in order to sustain a high functional diversity in southern Transylvania in the future.

关键词： agricultural intensification bird communities butterfly communities farmland heterogeneity land abandonment low-intensive agriculture RLQ analysis Transylvania,Romania

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