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the paternal epigenome and embryogenesis： poising mechanisms for development

Asian Journal of Andrology 2011年第1期13卷 76-80页

作者： timothy g Jenkins Douglas t Carrell Andrology and IVF Laboratories Department of Surgery University of Utah Salt Lake City UT 84108 USA Department of Obstetrics and gynecology University of Utah School of Medicine Salt Lake City UT 84108 USA Department of Physiology University of Utah School of Medicine Salt Lake City UT 84108 USA

the scope of paternal contributions during early embryonic development has long been considered limited. Dramatic changes in chromatin structure throughout spermatogenesis have been thought to leave the sperm void of complex layers of epigenetic regulation over the DNA blueprint, thus leaving the balance of that regulation to the oocyte. However, recent work in the fields of epigenetics and male factor infertility has placed this long-held, and now controversial dogma, in a new light. Elegant studies investigating chromatin and epigenetic modifications in the developing sperm cell have provided new insights that may establish a more critical role for the paternal epigenome in the developing embryo. DNA methylation, histone tail modifications, targeted histone retention and protamine incorporation into the chromatin have great influence in the developing sperm cell. Perturbations in the establishment and/or maintenance of any of these epigenetic marks have been demonstrated to affect fertility status, ranging in severity from mild to catastrophic. Sperm require this myriad of chromatin structural changes not only to serve a protective role to DNA throughout spermatogenesis and future delivery to the egg, but also, it appears, to contribute to the developmental program of the future embryo. this review will focus on our current understanding of the epigenetics of sperm. We will discuss sperm-specific chromatin modifications that result in genes essential to development being poised for activation early in embryonic development, the disruption of which may result in reduced fecundity.

关键词： chromatin DNA methylation embryogenesis epigenetics histone modification male infertility

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Lattice BgK Simulation of Multipolar Vortex Formation

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Advances in Applied Mathematics and Mechanics 2010年第5期2卷 533-544页

作者： gábor Házi gábor tóth theoretical thermohydraulics group MTA KFKI Atomic Energy Research InstituteH-1525Konkoly Th29-33BudapestHungary Department of Physics and Chemistry Széchényi István UniversityH-9026Egyetem Tér 1GyörHungary

Analytical and numerical studies have shown that multipolar vortices can emerge in two-dimensional flow due to azimuthal normal mode perturbations of shielded *** has been found that mode 2 and 3 perturbations can lead to the formation of stable tripoles and quadrapoles,respectively,while higher order modes result in more complex unstable compound *** have used the lattice Boltzmann method to simulate the effect of azimuthal perturbations on shielded vortices at moderate Reynolds *** have found that azimuthal normal mode perturbations result in the formation of multipoles,which decay due to viscous *** could also observe that the outcome of such simulations is very sensitive to the displacement of perturbations above wavenumber-3 excitations,in spite of the significant viscosity we used.

关键词： Lattice Boltzmann method shielded vortex stability

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Pointwise Convergence of Cone-like Restricted two-dimensional Fejér Means of Walsh-Fourier Series

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Acta Mathematica Sinica,English Series 2010年第12期26卷 2295-2304页

作者： gyrgy gt Kroly NAgY Institute of Mathematics and Computer Sciences College of Nyíregyhza

For the two-dimensional Walsh system, gat and Weisz proved the a.e. convergence of Fejer means σnf of integrable functions, where the set of indices is inside a positive cone around the identical function, that is, β^-1≤n1/n2 ≤β is provided with some fixed parameter ~ 〉 1. In this paper we generalize the result of gat and Weisz. We not only generalize this theorem, but give a necessary and sufficient condition for cone-like sets in order to preserve this convergence property.

关键词： Walsh group Walsh system pointwise convergence Fejer means

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Construction of an Energy-Efficient Detour Non-Split Dominating Set in WSN

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Computers, Materials & Continua 2022年第10期73卷 689-700页

作者： g.Sheeba t.M.Selvarajan Department of Mathematics Government Engineering CollegeTrivandrum695035India Department of Mathematics Noorul Islam Centre for Higher EducationKumaracoilThuckalay629175India

Wireless sensor networks(WSNs)are one of the most important improvements due to their remarkable capacities and their continuous growth in various ***,the lifetime of WSNs is very confined because of the delimited energy limit of their sensor *** is the reason why energy conservation is considered the main exploration worry for *** this energy-efficient routing is required to save energy and to subsequently drag out the lifetime of *** this report we use the Ant Colony Optimization(ACO)method and are evaluated using the genetic Algorithm(gA),based on the Detour non-split dominant set(gA)In this research,we use the energy efficiency returnee non-split dominating set(DNSDS).A set S⊆V is supposed to be a DNSDS of g when the graph g=(V,E)is expressed as both detours as well as a non-split dominating set of *** the detour non-split domination number be addressed asγ_dns(g)and is the minimum order of its detour non-split dominating *** DNSDS of orderγdns(g)is aγdns-set of ***,theγ_dns(g)of various standard graphs is resolved and some of its general properties are contemplated.A connected graph usually has an order n with detour non-split domination number as n or n–1 are *** connected graphs of order n≥4 and detour diameter D≤4 with detour non-split dominating number n or n−1 or n−2 are additionally *** considering any pair of positive integers to be specific a and b,there exists a connected graph g which is normally indicated as dn(g)=a,γ(g)=b andγdns(g)=a+b−2,hereγdns(g)indicates the detour domination number and dn(g)indicates the detour number of a *** time is taken for the construction and the size of DNSDS are considered for examining the performance of the proposed *** simulation result confirms that the DNSDS nodes are energy efficient.

关键词： Domination number non-split domination number detour number detour non-split domination number

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Residuated Completely Simple Semigroups

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Algebra Colloquium 2014年第2期21卷 181-194页

作者： t.S. Blyth g.A. Pinto Mathematical Institute University of St Andrews Scotland Instituto Piaget Campus Universitario de Almada Quinta da Arreinela de Cima 2800-305 Almada Portugal Universidade Atlantica Instituto de Investigagao Cientifica e Tecnologica Fabrica da Polvora 2730-036 Barcarena Portugal

We consider particular compatible orders on a given completely simple semi- group Sx= M（（x）; I, A; P） where （x） is an ordered cyclic group with x 〉 1 and p11= x-1. Of these, only the lexicographic and bootlace orders yield residuated semigroups. With the lexicographic order, Sx is orthodox and has a biggest idempotent. With the bootlace order, the maximal idempotents of Sx are identified by specific locations in the sandwich matrix. In the orthodox case there is also a biggest idempotent and, for sandwich matrices of a given size, uniqueness up to ordered semigroup isomorphism is established.

关键词： lexicographic order bootlace order residuated completely simple semigroup

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the law as it relates to subsidence as a consequence of mining activity in Britain

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中国有色金属学会会刊：英文版 2005年第S1期15卷 258-261页

作者： g. t. Powell K. Leighfield University of glamorgan Wales United KingdomUniversity of Glamorgan Wales United Kingdom

Subsidence as a consequence of mining activity has been an onerous problem associated with mineral extraction in Britain. Mining law as it relates to subsidence has developed over several centuries. this paper will outline the legal implications for mineral subsidence and compensation, considering both common law and statute. Particular reference is made to the extraction of coal, salt in brine, protection of public utilities, working facilities orders, ironstone and ancient mining rights.

关键词： subsidence compensation coal working facilities orders

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Stochastic earthquake source model for ground motion simulation

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 1-34页

作者： P.R.Lekshmy S.t.g.Raghukanth Department of Civil Engineering

In the analysis and design of important structures with relatively long life spans, there is a need to generate strong motion data for possible large events. the source of an earthquake is characterized by the spatial distribution of slip on the fault plane. For future events, this is unknown. In this paper, a stochastic earthquake source model is developed to address this issue. Here, 1D and 2D stochastic models for slip distribution developed by Lavallée et al.(2006) are used. the random field associated with the slip distribution is heavy-tailed stable distribution which can be used for large events. Using 236 past rupture models, the spectral scaling parameter and the four stable or Levy's parameters against empirical relationship for known quantities like magnitude or fault length are developed. the model is validated with data from 411 stations of 1999 Chi-Chi earthquake. the simulated response spectrum showed good agreement to actual data. Further the proposed model is used to generate ground motion for the 1993 Killari Earthquake where strong motion data is not available. the simulated mean peak ground velocity was in turn related to the intensity(MSK) and compared against values in the literature.

关键词： stochastic slip distribution ground motion Levy’s parameters Killari earthquake

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Reciprocating sliding wear properties of sintered Al-B_(4)C composites

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International Journal of Minerals,Metallurgy and Materials 2022年第6期29卷 1261-1269页

作者： Mahmut Can Şenel Yusuf Kanca Mevlüt gürbüz Mechanical Engineering Department Ondokuz Mayıs UniversitySamsun 55169Turkey Mechanical Engineering Department Hitit UniversityÇorum 19169Turkey

the fabrication of boron carbide reinforced aluminum matrix composites(Al-B_(4)C)with various contents of B_(4)C(1wt%,6wt%,15wt%,and 30wt%)was performed by powder metallurgy,and the influence of the content of B_(4)C on their mechanical and tribological behavior was *** Al-30B_(4)C composites recorded the highest density(~2.54 g/cm^(3)),lowest porosity(4%),maximum Vickers hardness(HV~75),lowest weight loss(0.4 mg),and lowest specific wear rate(0.00042 mm^(3)/(N·m))under a load of 7 N,with an enhancement of 167%in hardness,a decrease of 75.8%in weight loss,and a decrease of 76.7%in the specific wear rate compared with pure *** addition,the scanning electron microscope images of the worn surface revealed that the Al-B_(4)C composite has the narrowest wear groove of 0.85 mm at a load of 7 N,and the main wear mechanism was observed as an abrasive wear *** to the friction analysis,the coefficient of friction between surfaces increased with increasing boron carbide content and with decreasing applied *** conclusion,B_(4)C is an effective reinforcement material in terms of tribological and mechanical performance of the Al-B_(4)C composites.

关键词： aluminum boron carbide composite wear friction

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Finite element models to represent seismic activity of the Indian plate

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geoscience Frontiers 2017年第1期8卷 81-91页

作者： S.Jayalakshmi S.t.g.Raghukanth Department of Civil Engineering Indian Institute of TechnologyMadras 600036India

Quantification of seismic activity is one of the most challenging problems faced by earthquake engineers in probabilistic seismic hazard analysis. Currently, this problem has been attempted using empirical approaches which are based on the regional earthquake recurrence relations from the available earth- quake catalogue. However, at a specified site of engineering interest, these empirical models are asso- ciated with large number of uncertainties due to lack of sufficient data. Due to these uncertainties, engineers need to develop mechanistic models to quantify seismic activity. A wide range of techniques for modeling continental plates provides useful insights on the mechanics of plates and their seismic activity. Among the different continental plates, the Indian plate experiences diffused seismicity. In India, although Himalaya is regarded as a plate boundary and active region, the seismicity database indicates that there are other regions in the Indian shield reporting sporadic seismic activity. It is expected that mechanistic models of Indian plate, based on finite element method, simulate stress fields that quantify the seismic potential of active regions in India, this article explores the development of a finite element model for Indian plate by observing the simulated stress field for various boundary conditions, geological and theological conditions. the study observes that the magnitude and direction of stresses in the plate is sensitive to these conditions, the numerical analysis of the models shows that the simulated stress field represents the active seismic zones in India.

关键词： Indian platePlate driving forcesFinite element modeSeismicityCratons

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Probabilistic assessment of surface level seismic hazard in India using topographic gradient as a proxy for site condition

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geoscience Frontiers 2015年第6期6卷 847-859页

作者： t.g.Sitharam Sreevalsa Kolathayar Naveen James Department of Civil Engineering Indian Institute of Science Department of Civil Engineering Indian School of Mines

this paper presents spatial variation of seismic hazard at the surface level for India,covering 6-38°N and 68-98°*** most recent knowledge on seismic activity in the region has been used to evaluate the hazard incorporating uncertainties associated with the seismicity parameters using different modeling *** types of seismic source models,*** sources,gridded seismicity model and areal sources,were considered to model the seismic sources and different sets of ground motion prediction equations were used for different tectonic provinces to characterize the attenuation *** hazard estimation at bedrock level has been carried out using probabilistic approach and the results obtained from various methodologies were combined in a logic tree *** seismic site characterization of India was done using topographic slope map derived from Digital Elevation Model *** paper presents estimation of the hazard at surface level,using appropriate site amplification factors corresponding to various site classes based on V_（S30） values derived from the topographic *** variation of surface level peak horizontal acceleration（PHA） for return periods of 475 years and 2475 years are presented as contour maps.

关键词： PSHA PgA topography Site amplification India

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