THAWS: automated design and deployment of heterogeneous wireless sensor networks

This research focuses on the design and implementation of a tool to speed-up the development and deployment of heterogeneous wireless sensor networks. The THAWS (Tyndall Heterogeneous Automated Wireless Sensors) tool can be used to quickly create and configure application-specific sensor networks, based on a list of application requirements and constraints. THAWS presents the user with a choice of options, in order to gain this information on the functionality of the network. With this information, THAWS uses code generation techniques to create the necessary code from pre-written templates and well-tested, optimized software modules from a library, which includes an implementation of novel plug-and-play sensor interface. These library modules can also be modified at the code generation stage. The application code and necessary library modules are then automatically compiled to form binary instruction files for each node in the network. The binary instruction files then wirelessly propagate through the network, and reprogram the nodes. This completes the task of targeting the wireless network towards a specific sensing application. THAWS is an adaptable tool that works with both homogeneous and heterogeneous networks built from wireless sensor nodes that have been developed in the Tyndall National Institute. Its advantage over traditional methods of WSN development is simplification of development

Extracellular RNA – a new predictor and a supposable mechanism of in-stent restenosis

Department of Interventional Cardiology, Institute of Cardiology, Chisinau, the Republic of MoldovaBackground: The evaluation of new predictors of negative coronary remodeling after angioplasty remains an adequate approach of interventional cardiology in the diagnosis and prognosis of in-stent restenosis (ISR). Previously we have demonstrated on a murine model of atherosclerosis that extracellular RNA (eRNA) increases proportionally to vascular injury progression, and a first activation of the blood RNAase is changed by its steady quantitative decline, a reason that suggests a plausible role of eRNA in coronary neointima hyperplasia. Material and methods: This article is aimed at the study of eRNA amount in a tissue pattern of a stent with restenosis as well as its correlation with such inflammatory predictors as macrophage number and TNF-alpha expression. Using the techniques of confocal microscopy and immunohistochemistry we have first proved that eRNA level significantly increases in the coronary wall of segments with ISR (the specimens have been taken postmortem from 19 patients exposed to angioplasty). Results: The rise in the assay has been closely correlated to restenosis degree, and in muscular media it has been 2-4 times beyond the control range estimated in the adjacent coronary segment without negative vascular remodeling. In the restenosis zone eRNA has risen by about 130% from minimal to severe ISR. Moreover, its level has been found markedly increased earlier also comparatively to the control pattern: by 62% in moderate and 128% in severe ISR. A key disclosed evidence is that eRNA is positively correlated with TNF-alpha level (r = +0.88) and the number of macrophages (r = +0.84), whereas the last is notably enhanced depending on ISR progression. Conclusions: The obtained outcomes result in 2 opportunities: 1. eRNA may be a feasible predictor of negative coronary remodeling, facilitating the prognosis of ISR risk; 2. eRNA may be singled out as a factor involved in the pathogenesis of neointima formation and hyperplasia due to its relation to the inflammatory process

The extracellular matrix collagen in the coronary in-stent restenosis

Department of Interventional Cardiology, Institute of Cardiology, Chisinau, the Republic of MoldovaBackground: Extracellular matrix is underlined as an important factor regulating morphofunctional integrity of vascular wall, and is actively involved in vascular remodeling. Although collagen turnover activation is supported in mechanical artery injury, its character remains still unknown in the in-stent restenosis (ISR). The aim of this study is to evaluate the change of collagen type I and type III metabolism and metalloproteinase-2 (MMP2) expression in ISR. Material and methods: Using the confocal microscopy and immunochemistry techniques, the expression of collagen I and III, the markers of collagen I synthesis and degradation (PICP and CITP), as well as the expression of MMP2 and its tissue inhibitor (TIMMP2) have been assayed in the tissue pattern of ISR taken from 19 died patients. In 24 patients with ISR the markers of collagen I turnover were determined in blood also and compared with markers of 11 healthy persons. Results: The collagen I degradation is markedly increased in ISR and prevails over its synthesis while the collagen III degradation is enough preserved that led to collagen III/I ratio raising by 4-7 times already in minimal ISR. The CITP value is progressively increasing during restenosis exacerbation that is associated with a similar decline of PICP resulted consequently in a 7-10 fold elevation of the CITP/PICP ratio in muscular media of restenosis. Importantly to note that analogous changes of collagen type I turnover markers are established in blood in patients with ISR: PINP decreasing by 53.32% and CITP rise by 187.6%. The collagen I metabolism modification was accompanied by multiply MMP2 quantity increase and TIMPP2 diminution. Conclusions: 1. Extracellular matrix reorganization is a hallmark of the in-stent restenosis basically being exhibited by excessive collagen I degradation and preserved collagen III, splitting in conditions of MMP2/TIMMP2 ratio raising proportionally to ISR degree. 2. The shift of the circulating markers of collagen I turnover (PINP and CITP) is near to marker dynamics estimated in restenosis tissue that suggests their diagnostic and predictive role concerning ISR evolution

Phase growth control in low temperature PLD Co: TiO2 films by pressure

This paper reports on the structural and optical properties of Co-doped TiO2 thin films grown onto (0001)Al2O3 substrates by non-reactive pulsed laser deposition (PLD) using argon as buffer gas. It is shown that by keeping constant the substrate temperature at as low as 310 degrees C and varying only the background gas pressure between 7 Pa and 70 Pa, it is possible to grow either epitaxial rutile or pure anatase thin films, as well as films with a mixture of both polymorphs. The optical band gaps of the films are red shifted in comparison with the values usually reported for undoped TiO2, which is consistent with n-type doping of the TiO2 matrix. Such band gap red shift brings the absorption edge of the Co-doped TiO2 films into the visible region, which might favour their photocatalytic activity. Furthermore, the band gap red shift depends on the films' phase composition, increasing with the increase of the Urbach energy for increasing rutile content. (C) 2012 Elsevier B.V. All rights reserved

Kernel Matching Pursuit for Large Datasets

Kernel matching pursuit is a greedy algorithm for building an approximation of a discriminant function as a linear combination of some basis functions selected from a kernel-induced dictionary. Here we propose a modification of the kernel matching pursuit algorithm that aims at making the method practical for large datasets. Starting from an approximating algorithm, the weak greedy algorithm, we introduce a stochastic method for reducing the search space at each iteration. Then we study the implications of using an approximate algorithm and we show how one can control the trade-off between the accuracy and the need for resources. Finally, we present some experiments performed on a large dataset that support our approach and illustrate its applicability