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141.
To meet the challenge of implementing rapidly advanced, time-consuming medical image processing algorithms, it is necessary to develop a medical image processing technology to process a 2D or 3D medical image dynamically on the web. But in a premier system, only static image processing can be provided with the limitation of web technology. The development of Java and CORBA (common object request broker architecture) overcomes the shortcoming of the web static application and makes the dynamic processing of medical images on the web available. To develop an open solution of distributed computing, we integrate the Java, and web with the CORBA and present a web-based medical image dynamic processing methed, which adopts Java technology as the language to program application and components of the web and utilies the CORBA architecture to cope with heterogeneous property of a complex distributed system. The method also provides a platform-independent, transparent processing architecture to implement the adva  相似文献   
142.
<正> This paper shows how the so called von Karman model can be obtained as a singular limitof a modified Mindlin-Timoshenko system when the modulus of elasticity in shear k tends to infinity,provided a regularizing term through a fourth order dispersive operator is added.Introducing dampingmechanisms,the authors also show that the energy of solutions for this modified Mindlin-Timoshenkosystem decays exponentially,uniformly with respect to the parameter k.As k→∞,the authors obtainthe damped von Karman model with associated energy exponentially decaying to zero as well.  相似文献   
143.
Family change, when adults depart or arrive around children, raises policy issues. Its measurement depends upon the evidence collected and from whom. This paper compares British children's histories obtained from fathers and mothers. The evidence, on one birth cohort of parents, comes from two sources: the National Child Development Study and the ONS Longitudinal Study. The resulting account of family change is not substantially different between parents. There is some under-reporting of children not living with their fathers. This is due to under-reporting by those included in the studies and to under-representation in them of absent fathers and lone parents.  相似文献   
144.
Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today's complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system (embedded in a multiple intelligent agent system) is proposed to predict the financial health of a company. In our model, each individual agent (classifier) makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge (represented by features) about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset.  相似文献   
145.
ATransportProtocolandItsFormalDescriptionforLocalNetworksLiLayuanWuhanTransportationUniversity,430063,P.R.China(ReceivedMay4...  相似文献   
146.
147.
The theorem of the paper Aggregation of Equivalence Relations, by Fishburn and Rubinstein, states a result already known. This theorem improves a result from Mirkin (1975) and appears as a corollary occurring in Leclerc (1984).
Resume L'unique théorème de l'article Aggregation of Equivalence Relations de Fishburn et Rubinstein est déja connu. Il améliore, en fait, un résultat de Mirkin (1975) et apparait en tant que corollaire dans Leclerc (1984).
  相似文献   
148.
Poly(MePEG2000cyanoacrylate-co-hexadecylcyanoacrylate) (PEG-PHDCA) nanoparticles have demonstrated their capacity to reach the rat central nervous system after intravenous injection. For insight into the transport of colloidal systems across the blood-brain barrier (BBB), we developed a relevant in vitro rat BBB model consisting of a coculture of rat brain endothelial cells (RBECs) and rat astrocytes. The RBECs used in our model displayed and retained structural characteristics of brain endothelial cells, such as expression of P-glycoprotein, occludin and ZO-1, and immunofluorescence studies showed the specific localization of occludin and ZO1. The high values of transendothelial electrical resistance and low permeability coefficients of marker molecules demonstrated the functionality of this model. The comparative passage of polyhexadecylcyanoacrylate and PEG-PHDCA nanoparticles through this model was investigated, showing a higher passage of PEGylated nanoparticles, presumably by endocytosis. This result was confirmed by confocal microscopy. Thanks to a good in vitro/in vivo correlation, this rat BBB model will help in understanding the mechanisms of nanoparticle translocation and in designing new types of colloidal carriers as brain delivery systems.Received 4 March 2005; accepted 14 April 2005  相似文献   
149.
The 13-amino acid peptide neurotensin (NT) was discovered over 30 years ago and has been implicated in a wide variety of neurotransmitter and endocrine functions. This review focuses on four areas where there has been substantial recent progress in understanding NT signaling and several functions of the endogenous peptide. The first area concerns the functional activation of the high-affinity NT receptor, NTR-1, including the delineation of the NT binding pocket and receptor domains involved in functional coupling to intracellular signaling pathways. The development of NT receptor antagonists and the application of genetic and molecular genetic approaches have accelerated progress in understanding NT function in several areas, including the involvement of NT in antipsychotic drug actions, psychostimulant sensitization and the modulation of pain, and these are reviewed in that order. There is now substantial evidence indicating that NT is required for certain antipsychotic drug actions and that the peptide plays a key role in stress-induced analgesia.Received 18 March 2005; received after revision 9 May 2005; accepted 23 May 2005  相似文献   
150.
Diacylglycerol (DAG) was discovered as a potent lipid second messenger with protein kinase C (PKC) as its major cellular target more than 25 years ago. There is increasing evidence of significant complexity within lipid signaling, and the classical DAG-PKC model no longer stands alone but is part of a larger bioactive lipid universe involving glycerolipids and sphingolipids. Multiple layers of regulation exist among PKC- and DAG-metabolizing enzymes such as phosphatidylcholine (PC)-specific phospholipase D, and cross-talk exists between the glycerolipid and sphingolipid pathways, with PKC at the center. Currently, there is intense interest in the question of whether DAG derived from PC can function as a lipid second messenger and regulate PKC analogous to DAG derived from phosphatidylinositol-4,5-bisphosphate (PIP2). To address these issues and incorporate DAG-PKC and other signaling pathways into an expanded view of cell biology, it will be necessary to go beyond the classical approaches and concepts.Received 29 November 2004; received after revision 18 January 2005; accepted 4 March 2005This work is dedicated to the memory of Dr. Yasutomi Nishizuka, the discoverer of protein kinase C, who was both a gentleman and a scientist.  相似文献   
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