167 research outputs found

    Underwater acoustic noise modelings and some consequences for array processing

    Get PDF
    The modeling of the underwater acoustics noises appears as an essential component of the design of sonar or related systems . In a signal processing framework, we present a review of different noises in this domain and of associated models . Those must be, in fact, matched to the processing of the received signais . Then, are presented examples of interactions between processing and noise modeling, trying to show the importance of this last in the obtained results . Complexity and diversity of the approaches imply that this synthesis can only be incomplete : it is limited to the second order modeling and to the passive systems.We present a review of different noises in this domain and of associated models. Those must be, in fact, matched to the processing of the received signals. Then, are presented examples of interactions between processing and noise modeling, trying to show the importance of this last in the obtained resultsLa modélisation des bruits d'acoustique sous-marine apparaît comme une composante fondamentale de la conception des systèmes sonar et systèmes analogues ou associés . On présente, dans l'esprit « traitement du signal », une revue de divers bruits rencontrés dans ce domaine et de diverses modélisations associées . Celles-ci se doivent d'être, dans les faits, adaptées au traitement effectué sur les signaux reçus . On présente donc des exemples d'interaction entre traitement et modélisation des bruits, tentant de mettre en évidence l'importance de cette dernière dans les résultats obtenus . La complexité et la diversité des approches font que cette synthèse ne peut être que partielle : en particulier, elle se limite aux modèles du second ordre et aux systèmes de traitement passifs

    Photo-fenton degradation of pentachlorophenol l: competition between additives and photolysis

    Get PDF
    [EN] In the present work, the photo-Fenton degradation of pentachlorophenol (PCP, 1 mg/L) has been studied under simulated and natural solar irradiation; moreover, the effect on the process efficiency of urban waste-derived soluble bio-based substances (SBO), structurally comparable to humic acids, has been investigated. Experiments showed a crucial role of PCP photolysis, present in the solar pilot plant and hindered by the Pyrex (R) filter present in the solar simulator. Indeed, the SBO screen negatively affects PCP degradation when working under natural solar light, where the photolysis of PCP is relevant. In contrast, in the absence of PCP photolysis, a significant improvement of the photo-Fenton process was observed when added to SBO. Furthermore, SBO were able to extend the application of the photo-Fenton process at circumneutral pH values, due to their ability to complex iron, avoiding its precipitation as oxides or hydroxides. This positive effect has been observed at higher concentration of Fe(II) (4 mg/L), whereas at 1 mg/L, the degradation rates of PCP were comparable in the presence and absence of SBO.This work was realized with the financial support of the academic interchange from the Marie Sklodowska-Curie Research and Innovation Staff Exchange project, funded by the European Commission H2020-MSCA-RISE-2014 within the framework of the research project Mat4treaT (Project number: 645551).Vergura, EP.; García-Ballesteros, S.; Vercher Pérez, RF.; Santos-Juanes Jordá, L.; Bianco Prevot, A.; Arqués Sanz, A. (2019). Photo-Fenton Degradation of Pentachlorophenol: Competition between Additives and Photolysis. Nanomaterials. 9(8):1-8. https://doi.org/10.3390/nano9081157S189

    Deux méthodes de comparaison d'images pour l'identification d'objets à partir de données prospectives

    Get PDF
    Cette étude aborde le problème de l'identification d'objets mobiles à partir de données délivrées par un senseur prospectif dont la conception est actuellement en cours. Le but est d'estimer la faisabilité d'une telle identification à l'aide d'outils disponibles à ce jour en reconnaissance des formes. On présente dans ce papier la réalisation complète d'une chaîne de simulation, comprenant à la fois la génération des données (non disponibles) et la mise en place de processus capables de les exploiter dans un but d'identification. Des paramètres variables contrôlent la nature des images (richesse, niveau de bruit) tout au long de la simulation, ceci afin de pouvoir prendre en compte des données de qualité variable

    Trazodone plus pregabalin combination in the treatment of fibromyalgia: a two-phase, 24-week, open-label uncontrolled study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Although trazodone is frequently used by fibromyalgia patients, its efficacy on this disease has not been adequately studied. If effective, pregabalin, whose beneficial effects on pain and sleep quality in fibromyalgia have been demonstrated, could complement the antidepressant and anxiolytic effects of trazodone. The aim of the present study was to assess the effectiveness of trazodone alone and in combination with pregabalin in the treatment of fibromyalgia.</p> <p>Methods</p> <p>This was an open-label uncontrolled study. Trazodone, flexibly dosed (50-300 mg/day), was administered to 66 fibromyalgia patients during 12 weeks; 41 patients who completed the treatment accepted to receive pregabalin, also flexibly dosed (75-450 mg/day), added to trazodone treatment for an additional 12-week period. Outcome measures included the Fibromyalgia Impact Questionnaire (FIQ), the Pittsburgh Sleep Quality Index (PSQI), the Beck Depression Inventory (BDI), the Hospital Anxiety and Depression Scale (HADS), the Brief Pain Inventory (BPI), the Short-Form Health Survey (SF-36), and the Patients' Global Improvement scale (PGI). Emergent adverse reactions were recorded. Data were analyzed with repeated measures one-way ANOVA and paired Student's t test.</p> <p>Results</p> <p>Treatment with trazodone significantly improved global fibromyalgia severity, sleep quality, and depression, as well as pain interference with daily activities although without showing a direct effect on bodily pain. After pregabalin combination additional and significant improvements were seen on fibromyalgia severity, depression and pain interference with daily activities, and a decrease in bodily pain was also apparent. During the second phase of the study, only two patients dropped out due to side effects.</p> <p>Conclusions</p> <p>Trazodone significantly improved fibromyalgia severity and associated symptomatology. Its combination with pregabalin potentiated this improvement and the tolerability of the drugs in association was good.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00791739">NCT00791739</a></p

    Current clinical applications of spectral tissue Doppler echocardiography (E/E' ratio) as a noninvasive surrogate for left ventricular diastolic pressures in the diagnosis of heart failure with preserved left ventricular systolic function

    Get PDF
    Congestive heart failure with preserved left ventricular systolic function has emerged as a growing epidemic medical syndrome in developed countries, which is characterized by high morbidity and mortality rates. Rapid and accurate diagnosis of this condition is essential for optimizing the therapeutic management. The diagnosis of congestive heart failure is challenging in patients presenting without obvious left ventricular systolic dysfunction and additional diagnostic information is most commonly required in this setting. Comprehensive Doppler echocardiography is the single most useful diagnostic test recommended by the ESC and ACC/AHA guidelines for assessing left ventricular ejection fraction and cardiac abnormalities in patients with suspected congestive heart failure, and non-invasively determined basal or exercise-induced pulmonary capillary hypertension is likely to become a hallmark of congestive heart failure in symptomatic patients with preserved left ventricular systolic function. The present review will focus on the current clinical applications of spectral tissue Doppler echocardiography used as a reliable noninvasive surrogate for left ventricular diastolic pressures at rest as well as during exercise in the diagnosis of heart failure with preserved left ventricular systolic function. Chronic congestive heart failure, a disease of exercise, and acute heart failure syndromes are characterized by specific pathophysiologic and diagnostic issues, and these two clinical presentations will be discussed separately

    MWP phase shifters integrated in PbS-SU8 waveguides

    Get PDF
    We present new kind of microwave phase shifters (MPS) based on dispersion of PbS colloidal quantum dots (QDs) in commercially available photoresist SU8 after a ligand exchange process. Ridge PbS-SU8 waveguides are implemented by integration of the nanocomposite in a silicon platform. When these waveguides are pumped at wavelengths below the band-gap of the PbS QDs, a phase shift in an optically conveyed (at 1550 nm) microwave signal is produced. The strong light confinement produced in the ridge waveguides allows an improvement of the phase shift as compared to the case of planar structures. Moreover, a novel ridge bilayer waveguide composed by a PbS-SU8 nanocomposite and a SU8 passive layer is proposed to decrease the propagation losses of the pump beam and in consequence to improve the microwave phase shift up to 36.5° at 25 GHz. Experimental results are reproduced by a theoretical model based on the slow light effect produced in a semiconductor waveguide due to the coherent population oscillations. The resulting device shows potential benefits respect to the current MPS technologies since it allows a fast tunability of the phase shift and a high level of integration due to its small size

    Assessment of left ventricular diastolic function in children after successful repair of aortic coarctation

    Get PDF
    The purpose of the study was an assessment of left ventricular diastolic function in children after the successful repair of aortic coarctation (CoA). The prospective study concerned 32 pediatric patients after the CoA surgery. Tissue Doppler imaging parameters including strain and strain rate and the conventional echocardiographic indexes were analyzed in patients and healthy controls. Analysis of mitral annulus velocities, E–E′ ratio, strain, and strain rate of left ventricular mid-cavity segments and conventional indexes of mitral inflow showed the worsening of left ventricular diastolic mechanics in the study group compared to healthy controls. The E/E′ ratio was significantly higher in the study group compared to the control group (8.30 ± 3.24 vs. 6.95 ± 1.36; p < 0.05). The early diastolic strain rate to late diastolic strain rate ratio as well as early to late diastolic strain ratio of the left ventricular mid-cavity segments were significantly lower in the study group compared to healthy controls (1.81 ± 0.63 vs. 3.74 ± 1.53; p < 0.001 and 1.20 ± 0.49 vs. 3.41 ± 1.26; p < 0.001). No differences of the pulmonary venous flow parameters between those two groups were observed. The left ventricular diastolic mechanics in hypertensive patients after CoA repair did not differ from normotensive subjects. Hypertensive and normotensive children after surgical repair of CoA are found to have worsening of the left ventricular diastolic mechanics suggesting the impairment of the active myocardial relaxation

    Tissue Doppler echocardiographic quantification. Comparison to coronary angiography results in Acute Coronary Syndrome patients

    Get PDF
    BACKGROUND: Multiples indices have been described using tissue Doppler imaging (DTI) capabilities. The aim of this study was to assess the capability of one or several regional DTI parameters in separating control from ischemic myocardium. METHODS: Twenty-eight patients with acute myocardial infarction were imaged within 24-hour following an emergent coronary angioplasty. Seventeen controls without any coronary artery or myocardial disease were also explored. Global and regional left ventricular functions were assessed. High frame rate color DTI cineloop recordings were made in apical 4 and 2-chamber for subsequent analysis. Peak velocity during isovolumic contraction time (IVC), ejection time, isovolumic relaxation (IVR) and filling time were measured at the mitral annulus and the basal, mid and apical segments of each of the walls studied as well as peak systolic displacement and peak of strain. RESULTS: DTI-analysis enabled us to discriminate between the 3 populations (controls, inferior and anterior AMI). Even in non-ischemic segments, velocities and displacements were reduced in the 2 AMI populations. Peak systolic displacement was the best parameter to discriminate controls from AMI groups (wall by wall, p was systematically < 0.01). The combination IVC + and IVR< 1 discriminated ischemic from non-ischemic segments with 82% sensitivity and 85% specificity. CONCLUSION: DTI-analysis appears to be valuable in ischemic heart disease assessment. Its clinical impact remains to be established. However this simple index might really help in intensive care unit routine practice

    Trazodone for the treatment of fibromyalgia: an open-label, 12-week study

    Get PDF
    Background: Despite its frequent use as a hypnotic, trazodone has not been systematically assessed in fibromyalgia patients. In the present study have we evaluated the potential effectiveness and tolerability of trazodone in the treatment of fibromyalgia. Methods: A flexible dose of trazodone (50-300 mg/day), was administered to 66 fibromyalgia patients for 12 weeks. The primary outcome measure was the Pittsburgh Sleep Quality Index (PSQI). Secondary outcome measures included the Fibromyalgia Impact Questionnaire (FIQ), the Beck Depression Inventory (BDI), the Hospital Anxiety and Depression Scale (HADS), the Brief Pain Inventory (BPI), the Short-Form Health Survey (SF-36), and the Patients' Global Improvement Scale (PGI). Trazodone's emergent adverse reactions were recorded. Data were analyzed with repeated measures one-way ANOVA and paired Student's t test. Results: Trazodone markedly improved sleep quality, with large effect sizes in total PSQI score as well on sleep quality, sleep duration and sleep efficiency. Significant improvement, although with moderate effect sizes, were also observed in total FIQ scores, anxiety and depression scores (both HADS and BDI), and pain interference with daily activities. Unexpectedly, the most frequent and severe side effect associated with trazodone in our sample was tachycardia, which was reported by 14 (21.2%) patients. Conclusions: In doses higher than those usually prescribed as hypnotic, the utility of trazodone in fibromyalgia management surpasses its hypnotic activity. However, the emergence of tachycardia should be closely monitored. Trial registration: This trial has been registered with ClinicalTrials.gov number NCT-00791739

    EEMlab: A graphical user-friendly interface for fluorimetry experiments based on the drEEM toolbox

    Full text link
    [EN] Fluorescence has been widely employed for the characterization of organic matter. In particular, excitation emission matrixes (EEM) provide important qualitative information on its composition. However, the application of this technique is limited by the mathematical complexity involved, which requires the use of PARAFAC for deconvolution of the EEM in their components. To overcome the numerical problem specific MATLAB toolboxes for the PARAFAC deconvolution have been implemented (e.g. drEEM). This toolbox is widely used by the scientific community but its intrinsic complexity in terms of programming knowledge makes it difficult to use. In this regard and in order to facilitate the first approximation to the PARAFAC programming problem, this paper describes and offers to the community the EEMlab software application: a graphical user-firendly interface for fluorimetry experiments based on the drEEM toolbox. The interface is developed in order to facilitate not only the intuitive use of the drEEM (no previous MATLAB knowledge is needed) but also to automate many repetitive tasks (as the data load or the modeling loop) or even to manage the different formats of files being produced by all the devices involved in the process. In order to validate the EEMlab, the same experiment documented by the drEEM is reproduced. In addition, the EEMlab is tested again with conducting a new fluorimetry experiment and the results are presented at the end of the paper. Finally to appoint a reference to the public web site pabmitor.webs.upv.es/eemlab in where all the components of the EEMlab GUI (software, tutorial and datasets) are publicly available to the readers.The authors want to thank the financial support of the Generalitat Valenciana, Conselleria d'Educacio, Cultura i Esport (Spain) [GV/2015/074]. The authors want to thank the financial support of Ministerio de Educacion y Ciencia (Spain)(CTQ2015-69832-C4-4-R). Sara Garcia-Ballesteros would like to thank Ministerio de Economia y Competitividad (Spain) for her fellowship (BES-2013-066201). The authors want to thank Dr. F.S. García Einschlag who has independently tested the EEMlab and helped the authors to improve and validate the final version of the application.Micó Tormos, P.; García-Ballesteros, S.; Mora Carbonell, M.; Vicente Candela, R.; Amat Payá, AM.; Arqués Sanz, A. (2019). EEMlab: A graphical user-friendly interface for fluorimetry experiments based on the drEEM toolbox. Chemometrics and Intelligent Laboratory Systems. 188:6-13. https://doi.org/10.1016/j.chemolab.2019.03.001S61318
    corecore