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The role of retinoic acid in the commitment to meiosis

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Asian Journal of Andrology 2021年第6期23卷 549-554页

作者： Rachel L Gewiss m Christine Schleif michael D Griswold School of molecular Biosciences and Center for Reproductive Biology Washington State UniversityPullmanWA 99164USA

male meiosis is a complex process whereby spermatocytes undergo cell division to form haploid *** review focuses on the role of retinoic acid(RA)in meiosis,as well as several processes regulated by RA before cell entry into meiosis that are critical for proper meiotic entry and ***,we discuss RA metabolism in the testis as well as the roles of stimulated by retinoic acid gene 8(STRA8)and mEIOSIN,which are responsive to RA and are critical for *** assert that transcriptional regulation in the spermatogonia is critical for successful meiosis.

关键词： meiosis retinoic acid spermatogenesis testis

metachronal propulsion of non-Newtonian viscoelastic mucus in an axisymmetric tube with ciliated walls

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Communications in Theoretical Physics 2021年第3期73卷 43-54页

作者： S Shaheen K maqbool R Ellahi Sadiq m Sait Department of mathematics and Statistics International Islamic UniversityIslamabadPakistan Fulbright Fellow Department of Mechanical EngineeringUniversity of California RiversideCAUnited States of America Center for Communications and IT Research Research InstituteKing Fahd University of Petroleum&MineralsDhahran-31261Saudi Arabia

Cilia-induced flow of viscoelastic mucus through an idealized two-dimensional model of the human trachea is *** cilia motion is simulated by a metachronal wave pattern which enables the mobilization of highly viscous mucus even at nonzero Reynolds *** viscoelastic mucus is analyzed with the upper convected maxwell viscoelastic formulation which features a relaxation time and accurately captures normal stress generation in shear *** governing equations are transformed from fixed to wave(laboratory)frame with appropriate variables and resulting differential equations are perturbed about wave *** trachea is treated as an axisymmetric ciliated *** and axial distributions in axial velocity are calculated via the regular perturbation method and pressure rise is computed with numerical integration using symbolic software mATHEmATICA^(‘Tm’).The influence of selected parameters which is cilia length,and maxwell viscoelastic material parameter *** time for prescribed values of wave number are visualized *** rise is observed to increase considerably with elevation in both cilia length and relaxation time whereas the axial velocity is markedly *** simulations provide some insight into viscous-dominated cilia propulsion of rheological mucus and also serve as a benchmark for more advanced modeling.

关键词： viscoelastic mucus ciliated surface trachea inertial flow axisymmetric tube rheology flow

Referring Expressions: A Unified Approach

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外国语 2001年第2期24卷 1-22页

作者： K.m. Jaszczolt Department of Linguistics University of Cambridge

0. Introduction

关键词：语言学语言表达方式语言交际语言目的

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Default meanings

外国语 2006年第5期29卷 2-17页

作者： K.m.Jaszczolt University of Cambridge U.K.

In this paper I present some aspects of the controversy surrounding the semantics/pragmatics boundary and offer a possible solution in the form of Default Semantics. First, I present a brief introduction to Paul Grice’s approach to meaning as intentional communication. Next, I address the problem of the unit og which truth conditions should be predicated, assuming after Grice that the most successful approach to meaning has to make use of truth conditions. Further, I extend the discussion to some aspects of neo-Gricean pragmatics, most notably the issue of pragmatic processing that contributes to the truth-conditional representation and the proposed shortcuts through this processing in the form of default meanings. In the main part, I present the theory of Default Semantics (Jaszczolt 2005a), assess some arguments in favour of such an interactive theory of meaning that combines information from various sources, and address the issue of compositionality of meaning so conceived. In the final part, I apply the theory of Default Semantics to expressions with future-time reference in English in order to demonstrate the advantages of a framework that combines various types of information about utterance meaning in one, merged semantic representation. The main advantage turns out to be, in this domain, the unified treatment of all expressions with future-time reference.

关键词： semantics/pragmatics boundary underdetermination of meaning Default Semantics futurity in English compositionality of meaning merger representation utterance interpretation

Interevent times estimation of major and continuous earthquakes in Hormozgan region based on radial basis function neural network

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Geodesy and Geodynamics 2016年第1期7卷 64-75页

作者： m.R.mosavi m.Kavei m.Shabani Y.Hatem Khani Department of Electrical Engineering Iran University of Science and Technology Department of Physics University of Hormozgan Department of Electrical Engineering University of Imam Khomeini Marine Sciences

This paper presents a new method to estimate the time of important earthquakes in Hormozgan region with magnitude greater than 5.5 based on the Radial Basis Function （RBF） Neural Network （NN） models. Input vector to the network is composed of different seisrnicity rates between main events that are calculated in convenient and reliable way to create optimized training methods. It helps network with a limited number of training data to estimation. It is common for earthquakes modeling by data-driven methods in this case. In addition, the proposed method is combined with Rosenberg cluster method to remove aftershocks events from the history of catalog for NN to better process the data. The results show that created RBF model successfully estimates the interevent times between large and sequence earthquakes that can be used as a tool to predict earthquake, so that comparison with other NN structure, for example multi- Layer Perceptron （mLP） NN, reveals the superiority of the proposed method. Because of superiority proposed method has higher accuracy, lower costs and simpler network structure.

关键词： Interevent timesRadial basis functionNeural networksEarthquakes

Wormhole solutions and energy conditions in f(R,G)gravity

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Communications in Theoretical Physics 2021年第11期73卷 131-141页

作者： m Farasat Shamir G mustafa Saad Waseem mushtaq Ahmad National University of Computer and Emerging Sciences Lahore CampusPakistan Department of mathematics Shanghai UniversityShanghai200444China National University of Computer and Emerging Sciences Chiniot-Faisalabad CampusPakistan

In this manuscript,the traversable wormhole solutions have been explored in modified f(R,G)gravity by taking into consideration the model f(R,G)=R+rG2,where R is the Ricci curvature scalar and G is the Gauss–Bonnet *** acceptable form of the redshift function has been incorporated which is a non-constant in nature along with the implementation of those already defined in literature,the two shape functions namely b(r)=r/exp(r-r0)and b(r)=r0log(r+1)/log(r0+1).It is shown by studying the energy condition and through the graphical analysis that the null energy bounds for the effective energy-momentum tensor are generally violated for the presence of the ordinary matter in modified f(R,G)*** conditions associated with the matter content threading the wormhole geometries are evaluated and in general are found to favor the null energy conditions in the vicinity of the wormhole throat,the existence of the nonexotic wormhole geometries threaded by the matter has been confirmed under this gravity.

关键词： f(R,G)gravity energy conditions wormholes shape function

Wild bee distribution near forested landscapes is dependent on successional state

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Forest Ecosystems 2020年第2期7卷 159-171页

作者： Katherine A.Odanaka Sandra m.Rehan Department of Biological Sciences University of New HampshireDurhamNHUSA Department of Biology York UniversityTorontoONCanada

Background:Forested landscapes are valuable sources of ecosystem services especially in areas dedicated to intense agricultural *** from forest margin is known to influence the wild bee community in the landscape surrounding forested *** little is known regarding how bee communities distribute themselves in landscapes that exhibit different forest successional ***:We examined how land use type and distance from the forest edge affect the abundance and richness of the wild bee community across four forest successional *** were collected in sites representing four stages of forest succession and analyzed using generalized linear mixed models with negative binomial ***:Wild bee diversity is reduced in forested environments that maintain dense stands of trees and high canopy ***,distance from the forest edge was an important factor determining wild bee distribution in successional stages adjacent to forest ***,we found that bees maintain high specificity for distinct successional states and ***:Our results demonstrate how different successional stages can harbor different bee species and highlight the ability of microhabitats to act as reservoirs of bee diversity in and around forest ***,we found that maximizing successional patchiness across forested landscapes increases the amount of available habitat that can support a diverse suite of bees with different nesting biologies and behaviors.

关键词： Pollinator Forest margin Bee habitat Nesting biology Wild bees

Controlling the magnetic state of the proximate quantum spin liquid α-RuCl_(3) with an optical cavity

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npj Computational materials 2023年第1期9卷 265-274页

作者： Emil Viñas Boström Adithya Sriram martin Claassen Angel Rubio max Planck Institute for the Structure and Dynamics of matter Luruper Chaussee 14922761 HamburgGermany Department of Physics Stanford UniversityStanfordCA 94305USA Department of Physics and Astronomy University of PennsylvaniaPhiladelphiaPA 19104USA Center for Computational Quantum Physics Flatiron InstituteSimons FoundationNew York CityNY 10010USA

Harnessing the enhanced light-matter coupling and quantum vacuum fluctuations resulting from mode volume compression in optical cavities is a promising route towards functionalizing quantum materials and realizing exotic states of ***,we extend cavity quantum electrodynamical materials engineering to correlated magnetic systems,by demonstrating that a Fabry-Pérot cavity can be used to control the magnetic state of the proximate quantum spin liquidα-RuCl_(3).Depending on specific cavity properties such as the mode frequency,photon occupation,and strength of the light-matter coupling,any of the magnetic phases supported by the extended Kitaev model can be *** particular,in the THz regime,we show that the cavity vacuum fluctuations alone are sufficient to bringα-RuCl_(3) from a zigzag antiferromagnetic to a ferromagnetic *** external pumping of the cavity in the few photon limit,it is further possible to push the system into the antiferromagnetic Kitaev quantum spin liquid state.

关键词： state quantum magnetic

The regulatory subunits of PI3K, p85α and p85β, differentially affect BRD7-mediated regulation of insulin signaling

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Journal of molecular Cell Biology 2021年第12期13卷 889-901页

作者： Junsik m.Lee Renyan Liu Sang Won Park Division of Endocrinology Boston Children’s HospitalHarvard Medical SchoolBostonMA 02115USA

Bromodomain-containing protein 7 (BRD7) has been shown to interact with the regulatory subunit of phosphatidylinositol 3-kinase(PI3K), p85, in the insulin signaling pathway. Here, we show that upregulation of hepatic BRD7 improves glucose homeostasiseven in the absence of either p85 isoform, p85a or p85b. However, BRD7 leads to differential activation of downstream effectorproteins in the insulin signaling pathway depending on which isoform of p85 is present. In the presence of only p85a, BRD7 overexpression increases phosphorylation of insulin receptor (IR) upon insulin stimulation, without increasing the recruitment of p85to IR substrate. Overexpression of BRD7 also increases activation of Akt in response to insulin, but does not affect basal phosphorylation levels of Akt. meanwhile, the phosphorylation of glycogen synthase kinase 3b (GSK3b) is increased by overexpression ofBRD7. On the other hand, in the presence of only p85b, BRD7 overexpression does not affect phosphorylation levels of IR, and Aktphosphorylation is not affected by insulin stimulation following BRD7 upregulation. However, BRD7 overexpression leads to increased basal phosphorylation levels of Akt and GSK3b. These data demonstrate that BRD7’s action on glucose homeostasis doesnot require the presence of both p85 isoforms, and p85a and p85b have unique roles in insulin signaling in the liver.

关键词： PI3K BRD7 Akt insulin signaling