Middleware Design Framework for Mobile Computing

Mobile computing is one of the recent growing fields in the area of wireless networking. The recent standardization efforts accomplished in Web services, with their XML-based formats for registration/discovery, service description, and service access, respectively UDDI, WSDL, and SOAP, certainly represent an interesting first step towards open service composition, which MA supports for mobile computing are expected to integrate within their frameworks soon. A middle-ware that can work even if the network parameters are changed can be a better solution for successful mobile computing. A middle-ware is proposed for handling the entire existing problem in distributed environment. Middleware is about integration and interoperability of applications and services running on heterogeneous computing and communication devices. The services it provides - including identification, authentication, authorization, soft-switching, certification and security - are used in a vast range of global appliances and systems, from smart cards and wireless devices to mobile services and e-Commerce

Flow Analysis of Shale Oil and Gas

Imperial Users onl

Sulphated and Non-sulphated Disaccharides: Cellular And Molecular Mechanisms of Action in Macrophage Function

Sulphated disaccharides are degradation products of heparinase that are released by inflammatory cells at sites of inflammation. Recent studies have shown that heparin derived sulphated disaccharides inhibit macrophage TNF-α synthesis, delayed-type hypersensitivity, rat adjuvant and rat and mouse collagen induced arthritis, with indications that they act on T-cell and macrophage function. The mechanisms by which these occur are unknown. Therefore, this study aims to investigate the mechanism of action of sulphated disaccharides through which they produce an inhibitory effect. In this study, the impact of sulphated disaccharides was tested on monocyte-macrophage functions in vitro. In this study, it was established that sulphated disaccharides inhibit PMAstimulated macrophage-like cell differentiation (10⁻¹¹ – 10⁻⁴ M). The reduced numbers of adherent macrophages cells leads to the reduction of proinflammatory macrophages. Inhibition of phosphorylation of p38 and ERK1/2 was found and was directly proportional to sulphated disaccharide structural features, namely selective (HDS-I, HDS-III) or oligosulphation (SOS, DOS). Preincubation of monocytes with sulphated disaccharides inhibited PMA-induced calcium mobilisation. In addition, this study demonstrated that treatment with sulphated disaccharides induces a phenotypic switch of differentiated macrophages into an anti-inflammatory phenotype and also the pro-inflammatory phenotype into an anti-inflammatory phenotype. The current study provides an insight into the possibility of targeting inhibition of monocyte-macrophage-differentiation through inhibition of calcium mobilisation, leading to de-activation of p38 and ERK1/2 MAPK, TNF-α production, and ultimately inhibition of cell-differentiation induced cell surface adhesion molecule expression. In addition, sulphated disaccharides promote macrophage divergence towards an anti-inflammatory phenotype. The findings of this study indicate that sulphate disaccharides exhibit their inhibitory action even at very low concentrations, especially the oligosulphated compounds. Thus, suggesting a novel molecular mechanism for the treatment of macrophage-dependent chronic inflammatory diseases

A Multiple Hypothesis Testing Approach to Low-Complexity Subspace Unmixing

Subspace-based signal processing traditionally focuses on problems involving a few subspaces. Recently, a number of problems in different application areas have emerged that involve a significantly larger number of subspaces relative to the ambient dimension. It becomes imperative in such settings to first identify a smaller set of active subspaces that contribute to the observation before further processing can be carried out. This problem of identification of a small set of active subspaces among a huge collection of subspaces from a single (noisy) observation in the ambient space is termed subspace unmixing. This paper formally poses the subspace unmixing problem under the parsimonious subspace-sum (PS3) model, discusses connections of the PS3 model to problems in wireless communications, hyperspectral imaging, high-dimensional statistics and compressed sensing, and proposes a low-complexity algorithm, termed marginal subspace detection (MSD), for subspace unmixing. The MSD algorithm turns the subspace unmixing problem for the PS3 model into a multiple hypothesis testing (MHT) problem and its analysis in the paper helps control the family-wise error rate of this MHT problem at any level $\alpha \in [0,1]$ under two random signal generation models. Some other highlights of the analysis of the MSD algorithm include: (i) it is applicable to an arbitrary collection of subspaces on the Grassmann manifold; (ii) it relies on properties of the collection of subspaces that are computable in polynomial time; and ($iii$) it allows for linear scaling of the number of active subspaces as a function of the ambient dimension. Finally, numerical results are presented in the paper to better understand the performance of the MSD algorithm.Comment: Submitted for journal publication; 33 pages, 14 figure