141 research outputs found

    Time-frequency analysis of normal and abnormal biological signals

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    Due to the non-stationary, multicomponent nature of biomedical signals, the use of time-frequency analysis can be inevitable for these signals. The choice of the proper time-frequency distribution (TFD) that can reveal the exact multicomponent structure of biological signals is vital in many applications, including the diagnosis of medical abnormalities. In this paper, the instantaneous frequency (IF) estimation using four well-known TFDs is applied for analyzing biological signals. These TFDs are: the Wigner-Ville distribution (WVD), the Choi-Williams distribution (CWD), the Exponential T-distribution (ETD) and the Hyperbolic T-distribution (HTD). Their performance over normal and abnormal biological signals as well as over multicomponent frequency modulation (FM) signals in additive Gaussian noise was compared. Moreover, the feasibility of utilizing the wavelet transform (WT) in IF estimation is also studied. The biological signals considered in this work are the surface electromyogram (SEMG) with the presence of ECG noise and abnormal cardiac signals. The abnormal cardiac signals were taken from a patient with malignant ventricular arrhythmia, and a patient with supraventricular arrhythmia. Simulation results showed that the HTD has a superior performance, in terms of resolution and cross-terms reduction, as compared to other time-frequency distributions

    Client side decompression technique provides faster DNA sequence data delivery

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    DNA sequences are generally very long chains of sequentially linked nucleotides. There are four different nucleotides and combinations of these build the nucleotide information of sequence files contained in data sources. When a user searches for any sequence for an organism, a compressed sequence file can be sent from the data source to the user. The compressed file then can be decompressed at the client end resulting in reduced transmission time over the Internet. A compression algorithm that provides a moderately high compression rate with minimal decompression time is proposed in this paper. We also compare a number of different compression techniques for achieving efficient delivery methods from an intelligent genomic search agent over the Interne

    Investigation of the structural and functional relationships of oneogene proteins

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    Proteins are the biomolecular workhorses driving the most biological processes in any living organism. These processes are based on selective interactions between particular proteins. So far, the rules governing the coding of the protein's biological function, i.e. its ability to selectively interact with other biomolecules, have not been elucidated. The resonant recognition model (RRM) is a novel physicomathematical approach established to analyze the interaction between a protein and its target. The RRM assumes that the specificities of protein interactions are based on the resonant electromagnetic energy transfer at the specific frequency for each interaction. One of the main applications of this model is to predict the location of a protein's biological active site(s) using digital signal processing. This paper incorporates the continuous wavelet transform (CWT) into the RRM to predict the active sites, for a chosen protein example. We have investigated the oncogene functional group using digital signal analysis methods, in particular Fourier transform and CWT; determined oncogenes' characteristic frequency and functional active sites; and performed the design of the peptide analogous. The results obtained provide new insights into the structure-function relationships of the analyzed oncogene protein family

    Aggregation of frictional particles due to capillary attraction

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    Capillary attraction between identical millimeter sized spheres floating at a liquid-air interface and the resulting aggregation is investigated at low Reynolds number. We show that the measured capillary forces between two spheres as a function of distance can be described by expressions obtained using the Nicolson approximation at low Bond numbers for far greater particle sizes than previously assumed. We find that viscous hydrodynamics interactions between the spheres needs to be included to describe the dynamics close to contact. We then consider the aggregates formed when a third sphere is added after the initial two spheres are already in contact. In this case, we find that linear superposition of capillary forces describes the observed approach qualitatively but not quantitatively. Further, we observe an angular dependence of the structure due to a rapid decrease of capillary force with distance of separation which has a tendency to align the particles before contact. When the three particles come in contact, they may preserve their shape or rearrange to form an equilateral triangle cluster - the lowest energy state - depending on the competition between attraction between particles and friction. Using these observations, we demonstrate that a linear particle chain can be built from frictional particles with capillary attraction.Comment: accepted for Physical Review

    Development of a conductive photoresist with a mixture of SU-8 and HCL doped polyaniline

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    A novel electrically conductive photoresist has been formulated to fabricate microcomponents. The developed conductive photoresist is based upon SU-8 photopolymer, an insulating negative-tone epoxy, in which protonically doped polyaniline (PANI) nanoparticles have been dispersed to enhance the electrical properties. The characteristics of this new conductive photoresist have been studied via electrical measurements. The process for preparing the conductive films from the combination of EB (Emeraldine base) PANI, SU-8 and NMP (N-methyl-2-pyrrolidinone) will be presented. Different weight percentages (wt%) of SU-8 in the above combination have been prepared and spin coated to form thin-films which have been protonated with HCl. The conductivities of the thin- films were measured using a four point probe. The highest conductivity achieved was approximately 1.6 S/cm for the mixture of 10 wt% of SU-8 25 with EB-PANI mixed with NMP. The morphology of the thin-films was studied using a scanning electron microscopy (SEM)

    ‘The International Teacher Leadership project,’ a case of international action research.

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    Copyright CARNThe paper arises from the International Teacher Leadership project, a research and development project involving researchers and practitioners in 14 European countries. The paper provides a conceptual exploration of the idea of teacher leadership and its role in educational reform, central to which is the idea that teachers, regardless of their level of power and organisational position, can engage in the leadership of enquiry-based development activity aimed at influencing their colleagues and embedding improved practices in their schools. The paper provides an outline of the project’s methodology which builds on that used in the Carpe Vitam Leadership for Learning project (Frost, 2008a). It is a form of collaborative action research which is highly developmental and discursive. It seeks to identify principles, strategies and tools that can be applied in a range of cultural settings. The paper includes a thematic analysis of the cultural contexts and policy environments of the participating countries in order to identify the obstacles to teacher leadership and to inform the nature of the support strategies employed

    Influence of a Concurrent Exercise Training Intervention during Pregnancy on Maternal and Arterial and Venous Cord Serum Cytokines: The GESTAFIT Project

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    The aim of the present study was to analyze the influence of a supervised concurrent exercise-training program, from the 17th gestational week until delivery, on cytokines in maternal (at 17th and 35th gestational week, and at delivery) and arterial and venous cord serum. Fifty-eight Caucasian pregnant women (age: 33.5 +/- 4.7 years old, body mass index: 23.6 +/- 4.1kg/m(2)) from the GESTAFIT Project (exercise (n = 37) and control (n = 21) groups) participated in this quasi-experimental study (per-protocol basis). The exercise group followed a 60-min 3 days/week concurrent (aerobic-resistance) exercise-training from the 17th gestational week to delivery. Maternal and arterial and venous cord serum cytokines (fractalkine, interleukin (IL)-1 beta, IL-6, IL-8, IL-10, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha) were assessed using Luminex xMAP technology. In maternal serum (after adjusting for the baseline values of cytokines), the exercise group decreased TNF-alpha (from baseline to 35th week, p = 0.02), and increased less IL-1 beta (from baseline to delivery, p = 0.03) concentrations than controls. When adjusting for other potential confounders, these differences became non-significant. In cord blood, the exercise group showed reduced arterial IL-6 and venous TNF-alpha (p = 0.03 and p = 0.001, respectively) and higher concentrations of arterial IL-1 beta (p = 0.03) compared to controls. The application of concurrent exercise-training programs could be a strategy to modulate immune responses in pregnant women and their fetuses. However, future research is needed to better understand the origin and clearance of these cytokines, their role in the maternal-placental-fetus crosstalk, and the influence of exercise interventions on them

    Identification of candidate genes associated with fibromyalgia susceptibility in southern Spanish women: the al‑Ándalus project

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    Candidate-gene studies on fibromyalgia susceptibility often include a small number of single nucleotide polymorphisms (SNPs), which is a limitation. Moreover, there is a paucity of evidence in Europe. Therefore, we compared genotype frequencies of candidate SNPs in a well-characterised sample of Spanish women with fibromyalgia and healthy non-fibromyalgia women.This work was supported by the Spanish Ministry of Economy and Competitiveness [I+D+i DEP2010-15639, I+D+i DEP2013-40908-R to M.D.-F.; BES-2014-067612 to F.E.-L.]; the Spanish Ministry of Education [FPU2014/02518 to M.B.-C.]; the ConsejerĂ­a de Turismo, Comercio y Deporte, Junta de AndalucĂ­a [CTCD-201000019242-TRA to M.D.-F.]; ConsejerĂ­a de Salud, Junta de AndalucĂ­a [PI-0520-2016 to M.D.-F.], and the University of Granada, Plan Propio de InvestigaciĂłn 2016, Excellence actions: Units of Excellence; Unit of Excellence on Exercise and Health (UCEES). This work is part of a Ph.D. Thesis conducted in the Biomedicine Doctoral Studies of the University of Granada, Spai

    The Evolution of Expressing and Exchanging Cyber-Investigation Information in a Standardized Form

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    The growing number of investigations involving digital traces from various data sources is driving the demand for a standard way to represent and exchange pertinent information. Enabling automated combination and correlation of cyber-investigation information from multiple systems or organizations enables more efficient and comprehensive analysis, reducing the risk of mistakes and missed opportunities. These needs are being met by the evolving open-source, community-developed specification language called CASE, the Cyber-investigation Analysis Standard Expression. CASE leverages the Unified Cyber Ontology (UCO), which abstracts and expresses concepts that are common across multiple domains. This paper introduces CASE and UCO, explaining how they improve upon prior related work. The value of fully-structured data, representing provenance, and action lifecycles are discussed. The guiding principles of CASE and UCO are presented, and illustrative examples of CASE are provided using the default JSON-LD serialization
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