基于语料库的中国学术英语口语认知立场表达型式研究

认知立场标记语是交际者借助词汇手段对所述命题表明自身立场的一种语言手段,是话语构建的重要资源。通过自建国内小型学术口语语料库,以MICASE(密歇根大学学术口语语料库)为参照库,围绕动词、副词、形容词三类认知立场标记语,比较了中外学者在学术英语认知立场表达型式上的异同。结果表明,国内学者在学术英语口语交流中使用认知立场标记语总频数高于本族语学者;其中,动词、副词、形容词的使用频率在中外学术交流中存在显著性差异;对于国内学者来说,模糊性副词使用不足。

Seepage-stress coupling constitutive model of anisotropic soft rock

To provide a seepage-stress coupling constitutive model that can directly describe the seepage-stress coupling relationship, a series of one-dimensional seepage-stress coupling tests on two kinds of soft rock (argillaceous siltstone and brown mudstone) were performed by using an MTS-815.02 tri-axial rock mechanics test system, with which the stress-strain curves according to the seepage variation were obtained. Based on the experimental results and by employing Hooke's law, the formulation of the coefficient of strain-dependent permeability was presented and introduced to establish a coupling model. In addition, the mathematical expression and the incremental formulation for coupling model were advanced, in which five parameters that can be respectively determined by using the experimental results were included. The calculated results show that the proposed coupling model is capable of simulating the stress-strain relationship with considering the seepage-stress coupling in the nonlinear elastic stage of two kinds of soft rock.

THE EQUIVALENCE BETWEEN 2Gs AND 2Es AND A NEW PROOF TO PUMPING LEMMA

In this paper, the concept of type 2 expressions (2Es for short) is briefly introduced, and it is proved strictly that CFL class is precisely the language class expressed by 2Es. A new proof using 2Es to pumping lemma for CFLs is geven.

Performance Analysis of Physical Layer Security over α-η-κ-μ Fading Channels

In this paper, we consider the secure data transmission over α-η-κ-μ fading channels, which are recently proposed to encompass nearly all the well-known statistical models adopted in the literature. In particular, we address the secrecy performance in terms of the average secrecy capacity(ASC) and the secrecy outage probability(SOP), for which novel analytical expressions are derived. Simulation results verify the analysis and demonstrate the impact of the physical parameters on the secrecy performance of this new channel fading model.

Structure,expression,and developmental function of early divergent forms of metalloproteinases in Hydra

Metalloproteinases have a critical role in a broad spectrum of cellular processesranging from the break-down of extracellular matrix to the processing of signaltransduction-related proteins.These hydrolytic functions underlie a variety of mechanisms related to developmental processes as well as disease states.Structural analysis of metalloproteinases from both invertebrate and vertebrate species indicates that these enzymes are highly conserved and arose early during metazoan evolution.In this regard,studies from vari-ous laboratories have reported that a number of classes of metalloproteinases are found in hydra,a member of Cnidaria,the second oldest of existing animal phyla.These studies demonstrate that the hydra genome contains at least three classes of metalloproteinases to include members of the 1)astacin class,2)matrix met-alloproteinase class,and 3)neprilysin class.Functional studies indicate that these metalloproteinases play diverse and important roles in hydra morphogenesis and cell differentiation as well as specialized functions in adult polyps.This article will review the structure,expression,and function of these metalloproteinases in hydra.

Motion Estimation of an Omnidirectional Mobile Robot

The motion＇s generation consists in finding an analytic expression of a motion according to time. A Map road type planner or Cell decomposition provide to the motion generator some possible free crossing points of collision. The global trajectory＇s interpolation by a polynomial is generally not possible, because the degree of the polynomial increases with the number of crossing points which can generate vibrations or loops of the. trajectory. The solution consists in using polynomials in an inferior degree and to build the motion in pieces. The theoretical developments concern the motion＇s generation, the modeling of the vehicle, then the management of its redundancy steam-power. All these methods contribute to improve the robot precision （accuracy）. The authors are presenting the motion＇s generator which constructs into lines a continuous trajectory C2 while enabling the transformation of the crossing points into lines. The generator presented here as part of omnidirectional robot is adaptable to any kind of vehicle.

Theory of numerical modeling of constitutive relation for geotechnical materials

Under the direction of the principle of interaction between plastic volumetric and shear strains, the general expression of constitutive relation for geotechnical materials has been derived within the framework of irreversible thermo- dynamics. The constitutive modeling, in fact, is an inverse problem that belongs to the medium inverse problems of model identification, which is expressed as a reversion of coefficient of differential equation. Thus the constitutive modeling of geotechnical materials will become the reversion of coefficient functions of the general expression of constitutive relation, which is carried out in the stress field （p,q） by means Of numerical techniques, so that is called numerical modeling. Applying the numerical modeling, a number of plasticity-based models for clay and sand have been obtained, which are able to characterize the fundamental features of deformation for geotechnieal materials. In addition, the approach of numerical modeling also can be applied to the situation of unsaturated soils by means of the Bishop＇s effective stress formula and Khalili＇s expression of effective stress parameter.

Modeling of shear wave velocity in limestone by soft computing methods

The main purpose of current study is development of an intelligent model for estimation of shear wave velocity in limestone. Shear wave velocity is one of the most important rock dynamic parameters. Because rocks have complicated structure, direct determination of this parameter takes time, spends expenditure and requires accuracy. On the other hand, there are no precise equations for indirect determination of it; most of them are empirical. By using data sets of several dams of Iran and neuro-genetic, adaptive neuro-fuzzy inference system （ANFIS）, and gene expression programming （GEP） methods, models are rendered for prediction of shear wave velocity in limestone. Totally, 516 sets of data has been used for modeling. From these data sets, 413 ones have been utilized for building the intelligent model, and 103 have been used for their performance evaluation. Compressional wave velocity （Vp）, density （7） and porosity （.n）, were considered as input parameters. Respectively, the amount of R for neuro-genetic and ANFIS networks was 0.959 and 0.963. In addition, by using GEP, three equations are obtained; the best of them has 0.958R. ANFIS shows the best prediction results, whereas GEP indicates proper equations. Because these equations have accuracy, they could be used for prediction of shear wave velocity for limestone in the future.

Heat Capacity and Thermal Expansion of Water and Helium

Original expressions for heat capacity CV and its components, vibrational and configurational components of thermal expansion coefficient were established. The values of CV, Cvib, Cconf, Cvib and Cconf for water and helium 4He were calculated.

A novel method for singularity analysis of the 6-SPS parallel mechanisms

Singularity analysis is a basic problem of parallel mechanism, and this problem cannot be avoided in both workspace and motion planning. How to express the singularity locus in an analytical form is the research emphasis for many researchers for a long time. This paper presents a new method for the singularity analysis of the 6-SPS parallel mechanism. The rotation matrix is described by quaternion, and both the rotation matrix and the coordinate vectors have been expanded to four-dimensional forms. Through analyzing the coupling relationship between the position variables and the orientation variables, utilizing properties of the quaternion, eight equivalent equations can be obtained. A new kind of Jacobian matrix is derived from those equations, and the analytical expression of the singularity locus is obtained by calculating the determinant of the new Jacobian matrix. The singularity analysis of parallel mechanisms, whose moving platform actuated by 6 links and the vertices of both the base and the moving platforms has been placed on a circle respectively, can be solved by this analytical expression.

The observational constraint on constant-roll inflation

We discuss the constant-roll inflation with constant ∈1 and constant η. By using the method of Bessel function approximation, the analytical expressions for the scalar and tensor power spectra, the scalar and tensor spectral tilts, and the tensor to scalar ratio are derived up to the first order of ∈1. The model with constant ∈2 is ruled out by the observations at the 3σ confidence level, and the model with constant η is consistent with the observations at the 1σ confidence level. The potential for the model with constant η is also obtained from the Hamilton-Jacobi equation. Although the observations constrain the constant-roll inflation to be the slow-roll inflation, the ns-r results from the constant-roll inflation are not the same as those from the slow-roll inflation even when η- 0.01.

Single-cell atlas of domestic pig cerebral cortex and hypothalamus

The brain of the domestic pig(Sus scrofa domesticus)has drawn considerable attention due to its high similarities to that of humans.However,the cellular compositions of the pig brain(PB)remain elusive.Here we investigated the single-nucleus transcriptomic profiles of five regions of the PB(frontal lobe,parietal lobe,temporal lobe,occipital lobe,and hypothalamus)and identified 21 cell subpopulations.The cross-species comparison of mouse and pig hypothalamus revealed the shared and specific gene expression patterns at the single-cell resolution.Furthermore,we identified cell types and molecular pathways closely associated with neurological disorders,bridging the gap between gene mutations and pathogenesis.We reported,to our knowledge,the first single-cell atlas of domestic pig cerebral cortex and hypothalamus combined with a comprehensive analysis across species,providing extensive resources for future research regarding neural science,evolutionary developmental biology,and regenerative medicine.

An investigation of non-Newtonian fluid flow due to metachronal beating of cilia in a tube

The aim of this study is to explain theoretically the role of ciliary motion on the transport of epididymal fluid through the ductus efferentes of the male reproductive track. For this purpose, a mathematical model has been developed for the flow of a non-Newtonian fluid in an axisymmetric tube due to metachronal wave of cilia motion for the more realistic consequences. Carreau viscous fluid model is considered to see the rheological effects on the pumping characteristics of the flow. Regular perturbation method has been employed to obtain the analytical expressions for the stream function, the velocity field and a relation between the pressure difference and the volume flow rate. It is found that the volume flow rate is influenced significantly by Weissenberg number We and the cilia length parameter ε. The computational results are presented graphically to see the effects of various physical parameters. Finally, the analysis is applied and compared with the observed value of the flow rate of spermatic fluid in the ductus efferentes of the male reproductive track. The volume flow rate is reported closed to the estimated value 6 × 10^-3 ml/h in the human ductus efferentes when We = 0.5 and e is near by 0.25.

Pituitary transcriptome profile of liver cancer mice with different syndromes reveals the relevance of pituitary to the cancer and syndromes

OBJECTIVE: To investigate the relevance of the pituitary to liver syndromes and cancer by studying the pituitary transcriptome profile in liver cancer mice with different syndromes.METHODS: The quantitative four diagnosis and syndrome differentiation methods were used to screen normal control mice without syndromes(NC), liver cancer mice with poisonous pathogenic factors syndrome(PPFS), and Qi deficiency syndrome mice(QDS). An Affymetrix Gene Chip MouseExon 1.0 ST Array was performed to detect the gene expression of different groups. Gene clustering was applied to analyze the gene expression patterns of the PPFS and QDS groups compared with the NC group. The transcriptional networks analysis tool, Fun Net, was used to enrich the biological categories of differentially expressed genes in the PPFS and QDS groups.RESULTS: Biological categories of differentially expressed genes showed that excessive metabolism and extracellular matrix interaction, insufficient communication of cells(especially nerve cells), and the bidirectional regulation of genetic information processing were enriched in both syndromes. However, the degree of excessive metabolism in the PPFS group was higher than that in the QDS group.The hyperfunction of cancer and infection, and the hypofunction of the nervous and endocrine systems were obvious in the QDS group.CONCLUSION: The pituitary plays an important role in the development of liver cancer and syndromes. This study further studied the role of the pituitary in the combination of disease and syndromes.

Quasi-Conical Quantum Dot: Electron States and Quantum Transitions

The exactly solvable model of quasi-conical quantum dot, having a form of spherical sector, is proposed. Due to the specific symmetry of the problem the separation of variables in spherical coordinates is possible in the one- electron Sehrodinger equation. Analytical expressions for wave function and energy spectrum are obtained. It is shown that at small values of the stretch angle of spherical sector the problem is reduced to the conical QD problem. The comparison with previously performed works shows good agreement of results. As an application of the obtained results, the quantum transitions in the system are considered.