Supporting Effective Caching in a Wide-Area Distributed Location Service.

Abstract. Globe is a wide-area distributed system that supports mobile objects. To track and locate objects, we use a worldwide distributed location service, implemented as a search tree. An object registers its current position by storing its address in a nearby leaf node of the tree. This knowledge propagates up to the top of the tree, so every object can be found from the root. Remote objects can cache the location of an object. However, if the object moves, the cache entry is no longer valid. In this paper, we show how caching can be made to work effectively even in the presence of mobile objects. vrije Universitei

The distributed ASCI supercomputer project

The Distributed ASCI Supercomputer (DAS) is a homogeneous wide-area distributed system consisting of four cluster computers at different locations. DAS has been used for research on communication software, parallel languages and programming systems, schedulers, parallel applications, and distributed applications. The paper gives a preview of the most interesting research results obtained so far in the DAS project

Hungarian studies : HS ; a journal of the International Association of Hungarian Studies and Balassi Institute

Replication in the World-Wide Web covers a wide range of techniques. Often, the redirection of a client browser towards a given replica of a Web page is performed after the client's request has reached the Web server storing the requested page. As an alternative, we propose to perform the redirection as close to the client as possible in a fully distributed and transparent manner. Distributed redirection ensures that we find a replica wherever it is stored and that the closest possible replica is always found first. By exploiting locality, we can keep latency low. © 2005 Elsevier B.V. All rights reserved

Chlorella modulates insulin signaling pathway and prevents high-fat diet-induced insulin resistance in mice

Aims The search for natural agents that minimize obesity-associated disorders is receiving special attention. In this regard, the present study aimed to evaluate the prophylactic effect of Chlorella vulgaris (CV) on body weight, lipid profile, blood glucose and insulin signaling in liver, skeletal muscle and adipose tissue of diet-induced obese mice. Main methods Balb/C mice were fed either with standard rodent chow diet or high-fat diet (HFD) and received concomitant treatment with CV for 12 consecutive weeks. Triglyceride, free fatty acid, total cholesterol and fractions of cholesterol were measured using commercial assay. Insulin and leptin levels were determined by enzyme-linked immunosorbent assay (ELISA). Insulin and glucose tolerance tests were performed. The expression and phosphorylation of IRβ, IRS-1 and Akt were determined by Western blot analyses. Key findings Herein we demonstrate for the first time in the literature that prevention by CV of high-fat diet-induced insulin resistance in obese mice, as shown by increased glucose and insulin tolerance, is in part due to the improvement in the insulin signaling pathway at its main target tissues, by increasing the phosphorylation levels of proteins such as IR, IRS-1 and Akt. In parallel, the lower phosphorylation levels of IRS-1ser307 were observed in obese mice. We also found that CV administration prevents high-fat diet-induced dyslipidemia by reducing triglyceride, cholesterol and free fatty acid levels. Significance We propose that the modulatory effect of CV treatment preventing the deleterious effects induced by high-fat diet is a good indicator for its use as a prophylactic-therapeutic agent against obesity-related complications. © 2013 Elsevier Inc. All rights reserved.Aims the search for natural agents that minimize obesity-associated disorders is receiving special attention. In this regard, the present study aimed to evaluate the prophylactic effect of Chlorella vulgaris (CV) on body weight, lipid profile, blood glucose and insulin signaling in liver, skeletal muscle and adipose tissue of diet-induced obese mice. Main methods Balb/C mice were fed either with standard rodent chow diet or high-fat diet (HFD) and received concomitant treatment with CV for 12 consecutive weeks. Triglyceride, free fatty acid, total cholesterol and fractions of cholesterol were measured using commercial assay. Insulin and leptin levels were determined by enzyme-linked immunosorbent assay (ELISA). Insulin and glucose tolerance tests were performed. The expression and phosphorylation of IR?, IRS-1 and Akt were determined by Western blot analyses. Key findings Herein we demonstrate for the first time in the literature that prevention by CV of high-fat diet-induced insulin resistance in obese mice, as shown by increased glucose and insulin tolerance, is in part due to the improvement in the insulin signaling pathway at its main target tissues, by increasing the phosphorylation levels of proteins such as IR, IRS-1 and Akt. In parallel, the lower phosphorylation levels of IRS-1ser307 were observed in obese mice. We also found that CV administration prevents high-fat diet-induced dyslipidemia by reducing triglyceride, cholesterol and free fatty acid levels. Significance We propose that the modulatory effect of CV treatment preventing the deleterious effects induced by high-fat diet is a good indicator for its use as a prophylactic-therapeutic agent against obesity-related complications951455