Analysis of very low quality speech for mask-based enhancement

The complexity of the speech enhancement problem has motivated many different solutions. However, most techniques address situations in which the target speech is fully intelligible and the background noise energy is low in comparison with that of the speech. Thus while current enhancement algorithms can improve the perceived quality, the intelligibility of the speech is not increased significantly and may even be reduced. Recent research shows that intelligibility of very noisy speech can be improved by the use of a binary mask, in which a binary weight is applied to each time-frequency bin of the input spectrogram. There are several alternative goals for the binary mask estimator, based either on the Signal-to-Noise Ratio (SNR) of each time-frequency bin or on the speech signal characteristics alone. Our approach to the binary mask estimation problem aims to preserve the important speech cues independently of the noise present by identifying time-frequency regions that contain significant speech energy. The speech power spectrum varies greatly for different types of speech sound. The energy of voiced speech sounds is concentrated in the harmonics of the fundamental frequency while that of unvoiced sounds is, in contrast, distributed across a broad range of frequencies. To identify the presence of speech energy in a noisy speech signal we have therefore developed two detection algorithms. The first is a robust algorithm that identifies voiced speech segments and estimates their fundamental frequency. The second detects the presence of sibilants and estimates their energy distribution. In addition, we have developed a robust algorithm to estimate the active level of the speech. The outputs of these algorithms are combined with other features estimated from the noisy speech to form the input to a classifier which estimates a mask that accurately reflects the time-frequency distribution of speech energy even at low SNR levels. We evaluate a mask-based speech enhancer on a range of speech and noise signals and demonstrate a consistent increase in an objective intelligibility measure with respect to noisy speech.Open Acces

Class Separation Improvements in Pixel Classification Using Colour Injection

This paper presents an improvement in the colour image segmentation in the Hue Saturation (HS) sub-space. The authors propose to inject (add) a colour vector in the Red Green Blue (RGB) space to increase the class separation in the HS plane. The goal of the work is the development of an algorithm to obtain the optimal colour vector for injection that maximizes the separation between the classes in the HS plane. The chromatic Chrominace-1 Chrominance-2 sub-space (of the Luminance Chrominace-1 Chrominance-2 (YC1C2) space) is used to obtain the optimal vector to add. The proposal is applied on each frame of a colour image sequence in real-time. It has been tested in applications with reduced contrast between the colours of the background and the object, and particularly when the size of the object is very small in comparison with the size of the captured scene. Numerous tests have confirmed that this proposal improves the segmentation process, considerably reducing the effects of the variation of the light intensity of the scene. Several tests have been made in skin segmentation in applications for sign language recognition via computer vision, where an accurate segmentation of hands and face is required

Thirty-day outcomes in frail older patients discharged home from the emergency department with acute heart failure: effects of high-risk criteria identified by the DEED FRAIL-AHF trial

Objectives: To study the effect of high-risk criteria on 30-day outcomes in frail older patients with acute heart failure (AHF) discharged from an emergency department (ED) or an ED's observation and short-stay areas. Material and methods: Secondary analysis of discharge records in the Older AHF Key Data registry. We selected frail patients (aged > 70 years) discharged with AHF from EDs. Risk factors were categorized as modifiable or nonmodifiable. The outcomes were a composite endpoint for a cardiovascular event (revisits for AHF, hospitalization for AHF, or cardiovascular death) and the number of days alive out-of-hospital (DAOH) within 30 days of discharge. Results: We included 380 patients with a mean (SD) age of 86 (5.5) years (61.2% women). Modifiable risk factors were identified in 65.1%, nonmodifiable ones in 47.8%, and both types in 81.6%. The 30-day cardiovascular composite endpoint occurred in 83 patients (21.8%). The mean 30-day DAOH observed was 27.6 (6.1) days. Highrisk factors were present more often in patients who developed the cardiovascular event composite endpoint: the rates for patients with modifiable, nonmodifiable, or both types of risk were, respectively, as follows in comparison with patients not at high risk: 25.0% vs 17.2%, P = .092; 27.6% vs 16.7%, P = .010; and 24.7% vs 15.2%, P = .098). The 30-day DAOH outcome was also lower for at-risk patients, according to type of risk factor present: modifiable, 26.9 (7.0) vs 28.4 (4.4) days, P = .011; nonmodifiable, 27.1 (7.0) vs 28.0 (5.0) days, P = .127; and both, 27.1 (6.7) vs 28.8 (3.4) days, P = .005). After multivariate analysis, modifiable risk remained independently associated with fewer days alive (adjusted absolute difference in 30-day DAOH, -1.3 days (95% CI, -2.7 to -0.1 days). Nonmodifiable factors were associated with increased risk for the 30-day cardiovascular composite endpoint (adjusted absolute difference, 10.4%; 95% CI, -2.1% to 18.7%). Conclusion: Risk factors are common in frail elderly patients with AHF discharged home from hospital ED areas. Their presence is associated with a worse 30-day prognosis

Evaluación e intervención en el desarrollo de competencias éticas en estudiantes universitarios

Depto. de Antropología Social y Psicología SocialFac. de Ciencias Políticas y SociologíaFALSEsubmitte

Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay

We reconstruct the rare decays $B^+ \to K^+\mu^+\mu^-$, $B^0 \to K^{*}(892)^0\mu^+\mu^-$, and $B^0_s \to \phi(1020)\mu^+\mu^-$ in a data sample corresponding to $4.4 {\rm fb^{-1}}$ collected in $p\bar{p}$ collisions at $\sqrt{s}=1.96 {\rm TeV}$ by the CDF II detector at the Fermilab Tevatron Collider. Using $121 \pm 16$ $B^+ \to K^+\mu^+\mu^-$ and $101 \pm 12$ $B^0 \to K^{*0}\mu^+\mu^-$ decays we report the branching ratios. In addition, we report the measurement of the differential branching ratio and the muon forward-backward asymmetry in the $B^+$ and $B^0$ decay modes, and the $K^{*0}$ longitudinal polarization in the $B^0$ decay mode with respect to the squared dimuon mass. These are consistent with the theoretical prediction from the standard model, and most recent determinations from other experiments and of comparable accuracy. We also report the first observation of the $B^0_s \to \phi\mu^+\mu^- decay and measure its branching ratio${\mathcal{B}}(B^0_s \to \phi\mu^+\mu^-) = [1.44 \pm 0.33 \pm 0.46] \times 10^{-6}$using$27 \pm 6$signal events. This is currently the most rare$B^0_s$ decay observed.Comment: 7 pages, 2 figures, 3 tables. Submitted to Phys. Rev. Let

Search for a New Heavy Gauge Boson Wprime with Electron + missing ET Event Signature in ppbar collisions at sqrt(s)=1.96 TeV

We present a search for a new heavy charged vector boson $W^\prime$ decaying to an electron-neutrino pair in $p\bar{p}$ collisions at a center-of-mass energy of 1.96\unit{TeV}. The data were collected with the CDF II detector and correspond to an integrated luminosity of 5.3\unit{fb}^{-1}. No significant excess above the standard model expectation is observed and we set upper limits on $\sigma\cdot{\cal B}(W^\prime\to e\nu)$. Assuming standard model couplings to fermions and the neutrino from the $W^\prime$ boson decay to be light, we exclude a $W^\prime$ boson with mass less than 1.12\unit{TeV/}c^2 at the 95\unit{%} confidence level.Comment: 7 pages, 2 figures Submitted to PR

Measurements of the properties of Lambda_c(2595), Lambda_c(2625), Sigma_c(2455), and Sigma_c(2520) baryons

We report measurements of the resonance properties of Lambda_c(2595)+ and Lambda_c(2625)+ baryons in their decays to Lambda_c+ pi+ pi- as well as Sigma_c(2455)++,0 and Sigma_c(2520)++,0 baryons in their decays to Lambda_c+ pi+/- final states. These measurements are performed using data corresponding to 5.2/fb of integrated luminosity from ppbar collisions at sqrt(s) = 1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. Exploiting the largest available charmed baryon sample, we measure masses and decay widths with uncertainties comparable to the world averages for Sigma_c states, and significantly smaller uncertainties than the world averages for excited Lambda_c+ states.Comment: added one reference and one table, changed order of figures, 17 pages, 15 figure

Search for heavy bottom-like quarks decaying to an electron or muon and jets in ppˉp\bar{p} collisions at s=1.96\sqrt{s}=1.96 TeV

We report the most sensitive direct search for pair production of fourth-generation bottom-like chiral quarks ($b'$) each decaying promptly to $tW$. We search for an excess of events with an electron or muon, at least five jets (one indentified as due to a $b$ or $c$ quark) and an imbalance of transverse momentum using data from $p\bar{p}$ collisions collected by the CDF II detector at Fermilab with an integrated luminosity of 4.8 fb$^{-1}$. We observe events consistent with background expectation and calculate upper limits on the $b'$ pair production cross section ($\sigma_{b\bar{b'}}\lesssim 30$ fb for $m_{b'}>$375 GeV/$c^2$) and exclude $m_{b'}<372$ \gevcc at 95% confidence level.Comment: For submission to PR

Extracción enzimática de esteviolglucósidos en jugo de mora (Rubus Adenotrichus)

The goals of the study were to evaluate yield of the blackberry juice preparation, and at same time of the extraction of sweetener glycosides from dehydrated stevia leaves (Stevia rebaudiana Bertoni), by using enzymatic preparations. Five enzyme preparations were evaluated during the preparation of the sweetener with these glycosides. Two levels of the variables studied were evaluated: enzyme concentration (100 and 200ppm), and incubation period (15 30min), and using two extraction solvents at two temperatures: water and blackberry juice (at 50 and 35 °C, respectively). Efficiency and yield was analyzed by determining suspended insoluble solids (SIS), soluble solids (SS), and quantitation by cromatografía líquida de alta eficacia o High Performance Liquid Chromatography (HPLC) of the main esteviolglucósidos (stevioside and rebaudioside A). Statistical analysis data shown that the incubation time and the enzyme concentration in the enzyme complex did not affect total soluble solids values, but it does in the concentration of SIS, when using the commercial preparation Pectinex Ultra AFPL, as compared with the rest of the tested samples. Similarly, it is shown statistically significant differences in assessing the enzyme-time binomial, in the steviolglycosides extraction in water and blackberry juice. A high concentration of stevioside and rebaudioside A were achieved when using Pectinex Clear, at a concentration of 200 ppm during 30 seconds. However, the obtained values are similar to concentrations quantified in the control sample showing a slight influence of enzymes in the extraction of both steviolglycosides. This result corroborates that the diffusion of these compounds from the leaves to the medium, occurs primarily by the solubility thereof, rather than by hydrolysis caused by specific enzymes used in the study.Como estrategia para alcanzar mayor rendimiento en el procesamiento de pulpa de mora y al mismo tiempo extraer los esteviolglucósidos presentes en hojas deshidratadas de estevia (Stevia rebaudiana Bertoni), fueron evaluados 5 preparados enzimáticos durante la elaboración de un jugo de mora. Se evaluaron dos niveles de las variables consideradas: concentración de enzima (100 y 200ppm) y tiempo de incubación (15 y 30min) en dos medios de extracción: agua y pulpa de mora (a 50 y 35°C, respectivamente). La eficiencia del tratamiento fue analizado a través de la determinación de sólidos insoluasbles en suspensión, sólidos solubles y cuantificación por HPLC de esteviósido y rebaudiósido A.  En base al análisis estadístico aplicado se pudo afirmar que no existe ningún efecto,  ni en el tiempo de incubación, ni en la concentración del complejo enzimático, sobre los valores resultantes de sólidos solubles totales, pero si en los SIS, del preparado comercial ®Pectinex Ultra AFPL. En relación a la extracción de esteviolglucósidos, tanto en los ensayos de extracción en jugo de mora como en agua, hay diferencias estadísticamente significativas al valorar el binomio enzima*tiempo.  Las concentraciones más altas de esteviolglucósidos fueron alcanzadas empleando 200ppm de ®Pectinex Clear durante 30 segundos. A pesar de ello, los valores obtenidos son similares a las concentraciones cuantificadas en la muestra testigo lo que corrobora que la difusión de estos compuestos de las hojas al medio, ocurre principalmente por la solubilidad de los mismos, más que por la hidrólisis originada por las enzimas especificas empleadas en el estudio.

Production and characterization of cassava (Manihot esculenta crantz) flours using different thermal treatments

The aim of this study was to produce flours from the edible portion of cassava (Manihot esculenta Crantz) roots, treat them by heat in different forms (normal and pressure cooking, in limited and excess water conditions, and in the presence or absence of NaCl) and characterize them in their chemical composition, physical and functional properties. The flour preparation procedure affected both the chemical composition and gelatinization profile. The control (raw flour) and heat-treated samples displayed a set-back reduction. Pregelatinized flours showed decreased consistency and absorption indices, and augmented departure time, stability, tolerance index and time to breakdown values, as compared to control sample. These flours are suggested as potential ingredients in new or conventional product development