999 resultados para hemodynamic measurements


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In a leading service economy like India, services lie at the very center of economic activity. Competitive organizations now look not only at the skills and knowledge, but also at the behavior required by an employee to be successful on the job. Emotionally competent employees can effectively deal with occupational stress and maintain psychological well-being. This study explores the scope of the first two formants and jitter to assess seven common emotional states present in the natural speech in English. The k-means method was used to classify emotional speech as neutral, happy, surprised, angry, disgusted and sad. The accuracy of classification obtained using raw jitter was more than 65 percent for happy and sad but less accurate for the others. The overall classification accuracy was 72% in the case of preprocessed jitter. The experimental study was done on 1664 English utterances of 6 females. This is a simple, interesting and more proactive method for employees from varied backgrounds to become aware of their own communication styles as well as that of their colleagues' and customers and is therefore socially beneficial. It is a cheap method also as it requires only a computer. Since knowledge of sophisticated software or signal processing is not necessary, it is easy to analyze

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Little is known about the residual effects of crop residue (CR) and phosphorus (P) application on the fallow vegetation following repeated cultivation of pearl millet [Pennisetum glaucum (L.) R. Br.] in the Sahel. The objective of this study, therefore, was (i) to measure residual effects of CR, mulched at annual rates of 0, 500, 1000 and 2000 kg CR ha^-1, broadcast P at 0 and 13 kg P ha^-1 and P placement at 0, 1, 3, 5 and 7 kg P ha^-1 on the herbaceous dry matter (HDM) 2 years after the end of the experiment and (ii) to test a remote sensing method for the quantitative estimation of HDM. Compared with unmulched plots, a doubling of HDM was measured in plots that had received at least 500 kg CR ha^-1. Previous broadcast P application led to HDM increases of 14% compared with unfertilised control plots, whereas no residual effects of P placement were detected. Crop residue and P treatments caused significant shifts in flora composition. Digital analysis of colour photographs taken of the fallow vegetation and the bare soil revealed that the number of normalised green band pixels averaged per plot was highly correlated with HDM (r=0.86) and that red band pixels were related to differences in soil surface crusting. Given the traditional use of fallow vegetation as fodder, the results strongly suggest that for the integrated farming systems of the West African Sahel, residual effects of soil amendments on the fallow vegetation should be included in any comprehensive analysis of treatment effects on the agro-pastoral system.

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For millennia oasis agriculture has been the backbone of rural livelihood in the desertic Sultanate of Oman. However, little is known about the functioning of these oasis systems, in particular with respect to the C turnover. The objective was to determine the effects of crop, i.e. alfalfa, wheat and bare fallow on the CO2 evolution rate during an irrigation cycle in relation to changes in soil water content and soil temperature. The gravimetric soil water content decreased from initially 24% to approximately 16% within 7 days after irrigation. The mean CO2 evolution rates increased significantly in the order fallow (27.4 mg C m^−2 h^−1) < wheat (45.5 mg C m^−2 h^−1) < alfalfa (97.5 mg C m^−2 h^−1). It can be calculated from these data that the CO2 evolution rate of the alfalfa root system was nearly four times higher than the corresponding rate in the wheat root system. The decline in CO2 evolution rate, especially during the first 4 days after irrigation, was significantly related to the decline in the gravimetric water content, with r = 0.70. CO2 evolution rate and soil temperature at 5 cm depth were negatively correlated (r = -0.56,n = 261) due to increasing soil temperature with decreasing gravimetric water content.

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Absolute Kr 4s-electron photoionization cross sections as a function of the exciting-photon energy were measured by photon-induced fluorescence spectroscopy (PIFS) at improved primary-energy resolution. The cross sections were determined from threshold to 33.5 eV and to 90 eV with primary-photon bandwidths of 25 meV and 50 meV, respectively. The measurements were compared with experimental data and selected theoretical calculations for the direct Kr 4s-electron photoionization cross sections.

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Summary: Productivity, botanical composition and forage quality of legume-grass swards are important factors for successful arable farming in both organic and conventional farming systems. As these attributes can vary considerably within a field, a non-destructive method of detection while doing other tasks would facilitate a more targeted management of crops, forage and nutrients in the soil-plant-animal system. This study was undertaken to explore the potential of field spectral measurements for a non destructive prediction of dry matter (DM) yield, legume proportion in the sward, metabolizable energy (ME), ash content, crude protein (CP) and acid detergent fiber (ADF) of legume-grass mixtures. Two experiments were conducted in a greenhouse under controlled conditions which allowed collecting spectral measurements which were free from interferences such as wind, passing clouds and changing angles of solar irradiation. In a second step this initial investigation was evaluated in the field by a two year experiment with the same legume-grass swards. Several techniques for analysis of the hyperspectral data set were examined in this study: four vegetation indices (VIs): simple ratio (SR), normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) and red edge position (REP), two-waveband reflectance ratios, modified partial least squares (MPLS) regression and stepwise multiple linear regression (SMLR). The results showed the potential of field spectroscopy and proved its usefulness for the prediction of DM yield, ash content and CP across a wide range of legume proportion and growth stage. In all investigations prediction accuracy of DM yield, ash content and CP could be improved by legume-specific calibrations which included mixtures and pure swards of perennial ryegrass and of the respective legume species. The comparison between the greenhouse and the field experiments showed that the interaction between spectral reflectance and weather conditions as well as incidence angle of light interfered with an accurate determination of DM yield. Further research is hence needed to improve the validity of spectral measurements in the field. Furthermore, the developed models should be tested on varying sites and vegetation periods to enhance the robustness and portability of the models to other environmental conditions.

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TCP flows from applications such as the web or ftp are well supported by a Guaranteed Minimum Throughput Service (GMTS), which provides a minimum network throughput to the flow and, if possible, an extra throughput. We propose a scheme for a GMTS using Admission Control (AC) that is able to provide different minimum throughput to different users and that is suitable for "standard" TCP flows. Moreover, we consider a multidomain scenario where the scheme is used in one of the domains, and we propose some mechanisms for the interconnection with neighbor domains. The whole scheme uses a small set of packet classes in a core-stateless network where each class has a different discarding priority in queues assigned to it. The AC method involves only edge nodes and uses a special probing packet flow (marked as the highest discarding priority class) that is sent continuously from ingress to egress through a path. The available throughput in the path is obtained at the egress using measurements of flow aggregates, and then it is sent back to the ingress. At the ingress each flow is detected using an implicit way and then it is admission controlled. If it is accepted, it receives the GMTS and its packets are marked as the lowest discarding priority classes; otherwise, it receives a best-effort service. The scheme is evaluated through simulation in a simple "bottleneck" topology using different traffic loads consisting of "standard" TCP flows that carry files of varying sizes

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This paper presents the implementation details of a coded structured light system for rapid shape acquisition of unknown surfaces. Such techniques are based on the projection of patterns onto a measuring surface and grabbing images of every projection with a camera. Analyzing the pattern deformations that appear in the images, 3D information of the surface can be calculated. The implemented technique projects a unique pattern so that it can be used to measure moving surfaces. The structure of the pattern is a grid where the color of the slits are selected using a De Bruijn sequence. Moreover, since both axis of the pattern are coded, the cross points of the grid have two codewords (which permits to reconstruct them very precisely), while pixels belonging to horizontal and vertical slits have also a codeword. Different sets of colors are used for horizontal and vertical slits, so the resulting pattern is invariant to rotation. Therefore, the alignment constraint between camera and projector considered by a lot of authors is not necessary

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Introducción: A los pacientes con Insuficiencia Cardíaca (IC) estadio D candidatos a trasplante cardiaco se les realiza la determinación de las presiones de la arteria pulmonar por CCD considerada como prueba de oro. Se decidió conocer si la medición de las presión de la arteria pulmonar obtenidas por ECO TT tenían concordancia con las obtenidas por el CCDen estos paciente que fueron evaluados para trasplante cardiaco. Metodología: Se realizó una recolección retrospectiva de los datos consignados en las historias clínicas de todos los pacientes que fueron receptores de un trasplante cardiaco en la FCI-IC desde septiembre del 2005 hasta Mayo del 2013 y se determinó la concordancia entre la presión sistólica pulmonar evaluado por ECO TT y CCD. Resultados: Se incluyeron 46 pacientes. El 76,1% son hombres y con edad promedio de 46,4 ± 13,1. La PSAP estimada por CCD fue 48,3 ± 13,1 mmHg Vs 45,1 ± 12,1 mmHg por ECO TT. La fracción de eyección fue 15,1 ± 4,06% (IC: 13,95-16,36). El 75,9% de los pacientes tenían HTP moderada y severa. La concordancia entre la PSAP determinada por ambos métodos fue 0,475 (I,C: 0.256 - 0.694), y el coeficiente de correlación intraclase fue de 0,090, indicando una baja concordancia entre los dos métodos. Discusión: La determinación de las presiones pulmonares determinada por ECO TT tiene mala concordancia con las obtenidas por CCD. No se debe usar este estudio para excluir los pacientes candidatos a trasplante cardiaco ni para evaluar las variaciones de las misma en la evolución de la enfermedad.

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El compromiso del sistema cardiovascular es frecuente en los pacientes en estado crítico, por tanto la monitorización hemodinámica es esencial para un tratamiento apropiado dirigido a objetivos terapéuticos en este grupo de pacientes. La monitorización hemodinámica del gasto cardíaco y la estimación del volumen intravascular son fundamentales para el manejo de los pacientes pediátricos en estado crítico, la medición del gasto cardíaco es uno de los principales elementos para evaluar la situación hemodinámica y la perfusión tisular de un paciente ayudando a dirigir el tratamiento y a monitorizar la respuesta clínica en pacientes con choque séptico. La hipovolemia es una causa común para la falla circulatoria en pacientes en condición crítica, el encontrar un método confiable para medición de precarga es importante para guiar la administración de líquidos. Tradicionalmente se han utilizado medidas de la volemia asociadas como la presión venosa central (PVC), frecuencia cardiaca (FC), presión arterial (PA) y el gasto urinario. Estos indicadores tienen grandes factores de distracción que hacen que su valor sea limitado y por tanto se tengan que buscar alternativas más confiables. En años recientes se han postulado parámetros dinámicos para la evaluación de la precarga, entre ellos uno de los mas ampliamente estudiado es la medición de la variabilidad de Volumen sistólico (VVS); Este valor se basa en el concepto de que durante la inspiración, la disminución del retorno venoso produce una disminución del Volumen sistólico, lo cual se manifiesta como una disminución en la onda de pulso; Por tanto en una situación de hipovolemia esta diferencia será mayor, dado que será más evidente la disminución del volumen al final de la diástole. En adultos este parámetro se ha convertido en una herramienta útil para evaluar estado de volumen de los pacientes que se encuentran en estado crítico y ha demostrado su utilidad para predecir respuesta a administración de fluidos en diferentes poblaciones de pacientes. En la actualidad no hay estudios en niños que comparen la medición de VVS contra dichas medidas tradicionales de volemia.

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Introducción: La evaluación de injertos vasculares de submucosa de intestino delgado para la regeneración de vasos sanguíneos ha producido una permeabilidad variable (0-100%) que ha sido concurrente con la variabilidad en las técnicas de fabricación. Metodología: Investigamos los efectos de fabricación en permeabilidad y regeneración en un diseño experimental de 22factorial que combino: 1) preservación (P) o remoción (R) de la capa estratum compactum del intestino, y 2) deshidratada (D) o hidratada (H), dentro de cuatro grupos de estudio (PD, RD, PH, RH). Los injertos fueron implantados en las Arterias Carótidas de porcinos (ID 4.5mm, N=4, 7d). Permeabilidad, trombogenicidad, reacción inflamatoria, vascularización, infiltración de fibroblastos, perfil de polarización de macrófagos y fuerza tensil biaxial fueron evaluadas. Resultados: Todos los injertos PD permanecieron permeables (4/4), pero tuvieron escasa vascularización e infiltración de fibroblastos. El grupo RD permaneció permeable (4/4), presentó una extensa vascularización e infiltración de fibroblastos, y el mayor número del fenotipo de macrófagos (M2) asociado a regeneración. El grupo RH presentó menor permeabilidad (3/4), una extensa vascularización e infiltración de fibroblastos, y un perfil dominante de M2. El grupo PH presentó el menor grado de permeabilidad, y a pesar de mayor infiltración celular que PD, exhibió un fenotipo de macrófagos dominante adverso. La elasticidad de los injertos R evolucionó de una manera similar a las Carótidas nativas (particularmente RD, mientras que los injertos P mantuvieron su rigidez inicial. Discusión: Concluimos que los parámetros de fabricación afectan drásticamente los resultados, siendo los injertos RD los que arrojaron mejores resultados.

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Introducción: La simpatectomía es el tratamiento de la hiperhidrosis palmar y consiste en denervación simpática de miembros superiores que produce un efecto en el flujo sanguíneo al impactar la respuesta vasoconstrictora. El cambio en el flujo sanguíneo se puede evaluar a través de la onda fotopletismográfica. Metodología: Se realizaron 2 sesiones (presimpatectomía y postsimpatectomía) de 10 minutos en cada miembro superior en 28 pacientes obteniendo 79 señales fotopletismográficas distribuidas así: 37 presimpatectomía y 42 señales postsimpatectomía. De cada señal se analizó 1.5 minutos donde se tienen 80 ondas de fotopletismografía y se miden 6 variables: 1. Componente AC (componente pulsátil), 2. Componente DC (componente no pulsátil), 3. Relación entre AC/DC (índice de perfusión), 4. Area bajo la curva (AUC), 5. Tiempo entre el inicio de la onda y pico sistólico (T_DA) y 6. Tiempo entre cada onda de pulso (T_DD). Resultados: Aumentó 120% el componente AC y disminuyó 78% en DC del miembro superior derecho (MSD) con 99% de confiabilidad (p<0.001) entre presimpatectomía (n=18) y postsimpatectomía (n=21). AC/DC aumentó 55% con 95% de confiabilidad entre presimpatectomía (n=19) y postsimpatectomía (n=21) en el miembro superior izquierdo (p<0.05). No se encontró diferencia para T_DA, T_DD ni AUC. Discusión y Conclusión: La simpatectomía en pacientes con hiperhidrosis palmar produce un cambio en el flujo sanguíneo de los miembros superiores evidenciado por los cambios en el componente no pulsátil (DC) y pulsátil (AC) que es secundario a la vasodilatación consecuencia del bloqueo simpático por la denervación quirúrgica de los ganglios simpáticos torácicos.

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Atmospheric downwelling longwave radiation is an important component of the terrestrial energy budget; since it is strongly related with the greenhouse effect, it remarkably affects the climate. In this study, I evaluate the estimation of the downwelling longwave irradiance at the terrestrial surface for cloudless and overcast conditions using a one-dimensional radiative transfer model (RTM), specifically the Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART). The calculations performed by using this model were compared with pyrgeometer measurements at three different European places: Girona (NE of the Iberian Peninsula), Payerne (in the East of Switzerland), and Heselbach (in the Black Forest, Germany). Several studies of sensitivity based on the radiative transfer model have shown that special attention on the input of temperature and water content profiles must be held for cloudless sky conditions; for overcast conditions, similar sensitivity studies have shown that, besides the atmospheric profiles, the cloud base height is very relevant, at least for optically thick clouds. Also, the estimation of DLR in places where radiosoundings are not available is explored, either by using the atmospheric profiles spatially interpolated from the gridded analysis data provided by European Centre of Medium-Range Weather Forecast (ECMWF), or by applying a real radiosounding of a nearby site. Calculations have been compared with measurements at all sites. During cloudless sky conditions, when radiosoundings were available, calculations show differences with measurements of -2.7 ± 3.4 Wm-2 (Payerne). While no in situ radiosoundings are available, differences between modeling and measurements were about 0.3 ± 9.4 Wm-2 (Girona). During overcast sky conditions, when in situ radiosoundings and cloud properties (derived from an algorithm that uses spectral infrared and microwave ground based measurements) were available (Black Forest), calculations show differences with measurements of -0.28 ± 2.52 Wm2. When using atmospheric profiles from the ECMWF and fixed values of liquid water path and droplet effective radius (Girona) calculations show differences with measurements of 4.0 ± 2.5 Wm2. For all analyzed sky conditions, it has been confirmed that estimations from radiative transfer modeling are remarkably better than those obtained by simple parameterizations of atmospheric emissivity.

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This study investigates the relation between physical measurements of pure-tones, third-octave bands of noise and third-octave bands of speech and subjective judgments of auditory threshold, most-comfortable listening level (MCL) and uncomfortable-listening level (UCL) for three normally hearing listeners.

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This study provides detailed information on the ability of healthy ears to generate distortion product otoacoustic emissions (DPOAEs).