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Humans and mice separated more than 60 million years ago. Since then, evolution has led to a multitude of changes in their genomic sequences. The divergence of genes has resulted in differences both in the innate and adaptive immu...
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Humans and mice separated more than 60 million years ago. Since then, evolution has led to a multitude of changes in their genomic sequences. The divergence of genes has resulted in differences both in the innate and adaptive immune systems. In this chapter, we focus on species difference with regard to immunoglobulin class switch recombination (CSR). We have compared the immunoglobulin constant region gene loci from human and mouse, with an emphasis on the switch regions, germ line transcription promoters, and 3' enhancers. We have also compared pathways/factors that are involved in CSR. Although there are remarkable similarities in the cellular machinery involved in CSR, there are also a number of unique features in each species.
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A better understanding of the biological roles and the pathological consequences of thiol-dependent enzymes has emerged in recent years, and hence considerable progress has been made in identifying and delineating cysteine proteas...
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A better understanding of the biological roles and the pathological consequences of thiol-dependent enzymes has emerged in recent years, and hence considerable progress has been made in identifying and delineating cysteine proteases that can be considered promising drug targets from those involved in housekeeping functions. Cysteine proteases have been implicated in a wide variety of disease processes ranging from cardiovascular, inflammatory, viral and immunological disorders to cancer. The first milestone in drug development of cysteine protease inhibitors has probably been reached, as IDN-6556 (a broad spectrum caspase inhibitor) has recently received Orphan Drug label by the U.S. Food and Drug Administration for use in the treatment of the patients undergoing liver transplantation and other solid organ transplantation. IDN-6556, which blocks apoptosis, is in Phase II human clinical trial in patients undergoing liver transplantation. In addition, more than ten cysteine protease inhibitors are presently at various phases of clinical development/trials for diverse diseases. This review emphasises on the new development from the literature reports since the year 2000 in the exploration of potential cysteine proteases as prospective drug targets, and the investigation of promising inhibitors that can potentially be developed for the treatment of human diseases. Transglutaminases, another class of thiol-dependent enzymes, are not discussed here.
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Let N-epsilon denote the maximum number of spikes that a solution to Carrier's problem epsilon(2)y '' = 1 - y(2) -2(1-x(2))y, y(-1) = y(1) = 0 can have, where epsilon is a small positive parameter. We show that N epsilon is asympt...
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Let N-epsilon denote the maximum number of spikes that a solution to Carrier's problem epsilon(2)y '' = 1 - y(2) -2(1-x(2))y, y(-1) = y(1) = 0 can have, where epsilon is a small positive parameter. We show that N epsilon is asymptotically equal to [K/epsilon], where K = 0.4725. and the square brackets represent the greatest integer less than or equal to the quantity inside. If n(epsilon) stands for the number of solutions to this problem, then it is also shown that 4N(epsilon) - 3 收起
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This paper presents the development and validation of a parallel unstructured-grid fluid-structure interaction (FSI) solver for the simulation of unsteady incompressible viscous flow with long elastic moving and compliant boundari...
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This paper presents the development and validation of a parallel unstructured-grid fluid-structure interaction (FSI) solver for the simulation of unsteady incompressible viscous flow with long elastic moving and compliant boundaries. The Navier-Stokes solver on unstructured moving grid using the arbitrary Lagrangian Eulerian formulation is based on the artificial compressibility approach and a high-order characteristics-based finite-volume scheme. Both unsteady flow and FSI are calculated with a matrix-free implicit dual time-stepping scheme. A membrane model has been formulated to study fluid flow in a channel with an elastic membrane wall and their interactions. This model can be employed to calculate arbitrary wall movement and variable tension along the membrane, together with a dynamic mesh method for large deformation of the flow field. The parallelization of the fluid-structure solver is achieved using the single program multiple data programming paradigm and message passing interface for communication of data. The parallel solver is used to simulate fluid flow in a two-dimensional channel with and without moving membrane for validation and performance evaluation purposes. The speedups and parallel efficiencies obtained by this method are excellent, using up to 16 processors on a SGI Origin 2000 parallel computer. A maximum speedup of 23.14 could be achieved on 16 processors taking advantage of an improved handling of the membrane solver. The parallel results obtained are compared with those using serial code and they are found to be identical. Copyright (c) 2005 John Wiley & Sons, Ltd.
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Consider approximating functions based on a finite number of their samples. We show that adaptive algorithms are much more powerful than nonadaptive ones when dealing with piecewise smooth functions. More specifically, let F-r(1) ...
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Consider approximating functions based on a finite number of their samples. We show that adaptive algorithms are much more powerful than nonadaptive ones when dealing with piecewise smooth functions. More specifically, let F-r(1) be the class of scalar functions f : [ 0, T] -> R whose derivatives of order up to r are continuous at any point except for one unknown singular point. We provide an adaptive algorithm A(n)(ad) that uses at most n samples of f and whose worst case L-p error (1 收起
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This paper is concerned with the positive solutions of the boundary-value problem epsilon u '' - sigma(u) = -gamma, u(0) = u(1) = 0, where epsilon is a small positive parameter and gamma is a positive constant. The nonlinear term ...
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This paper is concerned with the positive solutions of the boundary-value problem epsilon u '' - sigma(u) = -gamma, u(0) = u(1) = 0, where epsilon is a small positive parameter and gamma is a positive constant. The nonlinear term sigma(u) behaves like a cubic; it vanishes only at u = 0, where sigma'(0) > 0 and sigma ''(0) < 0. This problem arises in a study of phase transitions in a slender circular cylinder composed of an incompressible phase-transforming material. Here, we determine the number of solutions to the problem for any given gamma, derive asymptotic formulas for these solutions, and show that the error terms associated with these formulas are exponentially small, except for one critical value of gamma. Our approach is again based on the shooting method used previously by Ou & Wong (Stud. Appl. Math. 112 (2004), 161-200).
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Fast and high-quality document clustering algorithms play an important role in providing intuitive navigation and browsing mechanisms by organizing large amounts of information into a small number of meaningful clusters. In partic...
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Fast and high-quality document clustering algorithms play an important role in providing intuitive navigation and browsing mechanisms by organizing large amounts of information into a small number of meaningful clusters. In particular, clustering algorithms that build meaningful hierarchies out of large document collections are ideal tools for their interactive visualization and exploration as they provide data-views that are consistent, predictable, and at different levels of granularity. This paper focuses on document clustering algorithms that build such hierarchical solutions and (i) presents a comprehensive study of partitional and agglomerative algorithms that use different criterion functions and merging schemes, and (ii) presents a new class of clustering algorithms called constrained agglomerative algorithms, which combine features from both partitional and agglomerative approaches that allows them to reduce the early-stage errors made by agglomerative methods and hence improve the quality of clustering solutions. The experimental evaluation shows that, contrary to the common belief, partitional algorithms always lead to better solutions than agglomerative algorithms; making them ideal for clustering large document collections due to not only their relatively low computational requirements, but also higher clustering quality. Furthermore, the constrained agglomerative methods consistently lead to better solutions than agglomerative methods alone and for many cases they outperform partitional methods, as well.
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The purpose of this paper is to reveal the influence of dissipation on travelling wave solutions of the generalized Pochhammer-Chree equation with a dissipation term, and provides travelling wave solutions for this equation. Apply...
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The purpose of this paper is to reveal the influence of dissipation on travelling wave solutions of the generalized Pochhammer-Chree equation with a dissipation term, and provides travelling wave solutions for this equation. Applying the theory of planar dynamical systems, we obtain ten global phase portraits of the dynamic system corresponding to this equation under various parameter conditions. Moreover, we present the relations between the properties of travelling wave solutions and the dissipation coefficient r of this equation. We find that a bounded travelling wave solution appears as a bell profile solitary wave solution or a periodic travelling wave solution when r = 0; a bounded travelling wave solution appears as a kink profile solitary wave solution when r > 0 is large; a bounded travelling wave solution appears as a damped oscillatory solution when r > 0 is small. Further, by using undetermined coefficient method, we get all possible bell profile solitary wave solutions and approximate damped oscillatory solutions for this equation. Error estimates indicate that the approximate solutions are meaningful.
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Out-of-pocket (OOP) payments are the principal means of financing health care throughout much of Asia. We estimate the magnitude and distribution of OOP payments for health care in fourteen countries and territories accounting for...
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Out-of-pocket (OOP) payments are the principal means of financing health care throughout much of Asia. We estimate the magnitude and distribution of OOP payments for health care in fourteen countries and territories accounting for 81% of the Asian population. We focus on payments that are catastrophic, in the sense of severely disrupting household living standards, and approximate such payments by those absorbing a large fraction of household resources. Bangladesh, China, India, Nepal and Vietnam rely most heavily on OOP financing and have the highest incidence of catastrophic payments. Sri Lanka, Thailand and Malaysia stand out as low to middle income countries that have constrained both the OOP share of health financing and the catastrophic impact of direct payments. In most low/middle-income countries, the better-off are more likely to spend a large fraction of total household resources on health care. This may reflect the inability of the poorest of the poor to divert resources from other basic needs and possibly the protection of the poor from user charges offered in some countries. But in China, Kyrgyz and Vietnam, where there are no exemptions of the poor from charges, they are as, or even more, likely to incur catastrophic payments.
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Clustering has a wide range of applications in life sciences and over the years has been used in many areas ranging from the analysis of clinical information, phylogeny, genomics, and proteomics. The primary goal of this article i...
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Clustering has a wide range of applications in life sciences and over the years has been used in many areas ranging from the analysis of clinical information, phylogeny, genomics, and proteomics. The primary goal of this article is to provide an overview of the various issues involved in clustering large biological datasets, describe the merits and underlying assumptions of some of the commonly used clustering approaches, and provide insights on how to cluster datasets arising in various areas within life sciences. We also provide a brief introduction to CLUTO, a general purpose toolkit for clustering various datasets, with an emphasis on its applications to problems and analysis requirements within life sciences.
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