689 research outputs found
Características clínicas y manejo de la fibrilación auricular en los servicios de urgencias hospitalarios
Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Medicina. Fecha de lectura: 25 de Marzo de 2011
An improved descriptor of cluster stability: application to small carbon clusters
Producción CientíficaThe mass spectra of gas-phase clusters in cluster beams have a rich structure where the relative heights of the peaks compared to peaks corresponding to clusters of neighbor sizes reveal the stability of the clusters as a function of the size N. In an analysis of the published mass spectrum of carbon clusters cations C + N with N ≤16 we have employed the most common descriptor of cluster stability, which is based on comparing the total energy of the cluster of size N with the averaged energies of clusters with sizes N+1 and N-1. Those energies have been obtained from density functional calculations. The comparison between the stability function and the mass spectrum leaves some experimental features unexplained; in particular, the correlation with the detailed variation of the height of the mass peaks as a function of size N is not satisfactory. We then propose a novel stability descriptor which improves matters substantially, in particular the correlation with the detailed variation of the height of the mass peaks. The new stability index is based on comparing the atom-evaporation energy of the cluster of size N with the averaged atom-evaporation energies of clusters with sizes N+1 and N-1. The substantial improvement achieved is attributed to the fact that evaporation energies are quantities directly connected with the processes controllig the cluster abundances in the beam.Ministerio de Economía, Industria y Competitividad ( Grants MAT2017-85089-C2-1-R / RYC-2015-17730)Junta de Castilla y Leon (Grant VA021G18)Universidad de Valladolid (Grupo de Física de Nanoestructuras), y Unión Europea a través de ERC-Synergy Program (Grant ERC-2013-SYG610256 NANOCOSMOS
Hydrogen quenches the size effects in carbon clusters
Producción CientíficaA characteristic fingerprint of atomic clusters is that their properties can vary in a non-smooth way with the cluster size N. This is illustrated herein by studying the cluster size dependence of several properties of neutral CN and cationic C+N carbon clusters: C–C bond lengths, cluster structure, intrinsic cluster stability, ionization energy, and spatial distribution of the reactivity index for charge exchange with electrophiles. Nonetheless, clusters can lose the size dependence of their properties by interaction with other chemical species, which is rationalized in this study by analyzing carbon clusters fully saturated with hydrogen to form linear alkanes, CNH2N+2. In all cases, the lowest energy structures are zigzagging linear chains, the variations of C–C bond lengths and Image ID:c9cp01114e-t1.gif angles with alkane size are very minor and smooth, the stability function shows practically no structure as a function of the alkane size, the ionization energies just decrease smoothly with alkane size, and the spatial distribution of the reactivity index is analogous and highly delocalized in all the alkanes. In summary, the interaction of carbon clusters with hydrogen to form alkanes quenches all the size-dependent features that the carbon clusters originally owned. The arrival at the quenching of the size effects follows an involved path. In each CNHn family with fixed N, the values of the properties of the molecules like the ionization potential, the electron affinity, and others show sizable oscillations as the number of hydrogen atoms grows from the pure carbon cluster to the alkane.Ministerio de Economía, Industria y Competitividad ( grants MAT2017-85089-C2-1-R / RYC-2015-17730)Comunidad de Madrid (FotoArt-CM Project P2018/NMT-4367)Junta de Castilla y León (Grant VA021G18)Universidad de Valladolid (GIR Grupo de Física de Nanoestructuras),y Unión Europea mediante el programa ERC-Synergy (Grant ERC-2013-SYG-610256 Nanocosmos
Incidence, Clinical Characteristics, Risk Factors and Outcomes of Acute Coronary Syndrome in Patients With COVID-19: Results of the UMC-19-S10
COVID-19; SARS-Cov-2; Síndrome coronari agutCOVID-19; SARS-Cov-2; Síndrome coronario agudoCOVID-19; SARS-Cov-2; Acute coronary syndromeBackground: There is a lack of knowledge about the real incidence of acute coronary syndrome (ACS) in patients with COVID-19, their clinical characteristics, and their prognoses. Objective: We investigated the incidence, clinical characteristics, risk factors, and outcomes of ACS in patients with COVID-19 in the emergency department. Methods: We retrospectively reviewed all COVID-19 patients diagnosed with ACS in 62 Spanish emergency departments between March and April 2020 (the first wave of COVID-19). We formed 2 control groups: COVID-19 patients without ACS (control A) and non-COVID-19 patients with ACS (control B). Unadjusted comparisons between cases and control subjects were performed regarding 58 characteristics and outcomes. Results: We identified 110 patients with ACS in 74,814 patients with COVID-19 attending the ED (1.48% [95% confidence interval {CI} 1.21-1.78%]). This incidence was lower than that observed in non-COVID-19 patients (3.64% [95% CI 3.54-3.74%]; odds ratio [OR] 0.40 [95% CI 0.33-0.49]). The clinical characteristics of patients with COVID-19 associated with a higher risk of presenting ACS were: previous coronary artery disease, age ≥60 years, hypertension, chest pain, raised troponin, and hypoxemia. The need for hospitalization and admission to intensive care and in-hospital mortality were higher in cases than in control group A (adjusted OR [aOR] 6.36 [95% CI 1.84-22.1], aOR 4.63 [95% CI 1.88-11.4], and aOR 2.46 [95% CI 1.15-5.25]). When comparing cases with control group B, the aOR of admission to intensive care was 0.41 (95% CI 0.21-0.80), while the aOR for in-hospital mortality was 5.94 (95% CI 2.84-12.4). Conclusions: The incidence of ACS in patients with COVID-19 attending the emergency department was low, around 1.48%, but could be increased in some circumstances. Patients with COVID-19 with ACS had a worse prognosis than control subjects with higher in-hospital mortalit
Thermal differences in the plantar surface of skin the foot after using three different lining materials for plantar orthotics.
The lining materials of plantar orthoses are chosen for their hardness, breathability, and moisture absorption, but without there being any clear scientific criterion. Thermographic analysis would provide information about the thermal response of the sole of the foot, and would thereby allow the choice to be adapted in accordance with this criterion. The objective of this study was to evaluate plantar temperatures after the use of three materials with different characteristics. Plantar temperatures were analyzed by using a FLIR E60BX thermographic camera on 36 participants (15 men and 21 women, 24.6 ± 8.2 years old, 67.1 ± 13.6 kg, and 1.7 ± 0.09 m). Measurements were made before and after (3 h) the use of three lining materials for plantar orthoses (Material 1: PE copolymer; Material 2: EVA; Material 3: PE-EVA copolymer) on different days. For Material 1 (PE), the temperature under the heel was significantly higher after exercise, increasing from 30.8 ± 2.9 °C to 31.9 ± 2.8 °C (p = 0.008), and negative correlations were found between room temperature and the pre/post temperature difference for the big toe (r = −0.342, p = 0.041) and the 1st metatarsal head (r = −0.334, p = 0.046). No significant pre/post temperature differences were found with the other materials. The three materials thermoregulated the plantar surface efficiently by maintaining the skin temperature at levels similar to those evaluated before exercise. If PE is used as a lining material, it should be avoided for the heel area in patients with hyperhidrosis or those with a tendency to suffer from skin pathologies due to excess moisture
Type of judge and decisions in dismissal cases: An analysis of Labour Courts in Spain
El objetivo de este artículo es profundizar en la relación existente entre las decisiones judiciales de lo social en España en los casos de despido y los costes asociados a la extinción de los contratos laborales. Primero justificamos que los cambios en la probabilidad de que un juez falle a favor de un trabajador afectan a los costes de despido del empleador. En segundo lugar, examinamos cómo difiere dicha probabilidad cuando el juez es titular o sustituto. Se observa una mayor dispersión en la resolución de los casos de los jueces sustitutos, y un significativo repunte en los años de crisis económica de los fallos judiciales a favor del trabajador al considerar los jueces titulares, siendo este más débil en los casos de los sustitutosThe aim of this paper is to examine in detail the relationship between the decisionsof the Spanish labour courts regarding dismissal, and the costs associated with the terminationof employment contracts. We explain the changes in the probability that a judge ruling infavour of a worker affects the effective firing costs that the employer faces. We also examine how this probability differs depending on whether the judge is in charge of the court or is asubstitute. There is a greater dispersion in the resolution of cases when there are substitute judges, with a significant rise, during the economic crisis, of court decisions in favour of theworkers with permanent judges, which is less so with substitute judge
SIGPAC y series multitemporales LANSAT 15 TM como estrategia híbrida de clasificación de usos de suelo para aplicaciones hidrológicas
El objetivo de este trabajo consiste en la obtención de un mapa de usos y coberturas de suelo para su
integración en un modelo hidrológico de balance de agua a lo largo de 2009. Los resultados de dicha
aplicación (evapotranspiración, humedad de suelo, necesidades de riego) se obtienen a escala de parcela,
con escala temporal diaria y contemplando los usos y coberturas más frecuentes en la zona. La herramienta
diseñada para aplicar el modelo (HidroMORE, Modelo Hidrológico de Estimación de Recarga y
Evapotranspiración) proporciona los resultados en forma de mapa imagen.
Con este fin, se presenta una alternativa híbrida de clasificación consistente en la combinación de la base de
datos vectorial del Sistema de Información Geográfica de Parcelas Agrícolas (SIGPAC), junto con una serie
multitemporal de imágenes Landsat 5 TM (Thematic Mapper) del año 2009. El primero aporta la definición
parcelaria, mientras que la segunda provee la información suficiente para resolver clases poco definidas en el
SIGPAC, especialmente la categoría ‘tierra arable’. Se utilizaron metodologías de teledetección como la
clasificación, la segmentación multitemporal y el NDVI (Normalized Difference Vegetation Index), junto con
herramientas SIG. El método propuesto supuso una mejora global de la precisión respecto a un método de
clasificación supervisada convencional del 20% para la zona de estudio en 2009, y con un coste operacional
muy bajo.The aim of this work consists on retrieving a land use-land cover map in order to integrate it in a water balance
model along 2009. The results of this application, i.e., evapotranspiration, soil moisture, irrigation rates, are
obtained at field scale, in a daily basis, and over the most representative agricultural uses. The model is
implemented in a computerized tool, HidroMORE, which provides image maps of the results.
A hybrid alternative of classification is presented for such hydrological application. It consisted in a
combination of the vectorial database from the Spanish Geographic Information System for Agricultural Plots
(SIGPAC) and a Landsat 5 TM multitemporal series of images for the year of study. The SIGPAC affords the
spatial shape of the plots, whereas the images allow the segmentation of some ambiguous categories, i.e.,
‘agricultural plots’. Remote sensing techniques (classification, segmentation, and NDVI, Normalized Difference
Vegetation Index) were used, as well as GIS tools. The proposed method improved by 20% the global accuracy comparing to a typical supervised classification in the study area along 2009, while the computational cost is
low
Android malware detection from Google Play meta-data: Selection of important features
Android malware has emerged in the last decade as a consequence of the increasing popularity of smartphones and tablets. While most previous work focuses on inherent characteristics of Android apps to detect malware, this study analyses indirect features to identify patterns often observed in malware applications. We show that modern Machine Learning techniques applied to collected metadata from Google Play can provide a first approach towards the detection of malware applications, and we further identify which features have the highest predictive power among the total.The authors would like to acknowledge the support of the project BigDatAAM (grant no. FIS2013-47532-C3-3-P) funded by the Spanish MINECO
Gestión económicamente optimizada del agua de riego en una explotación agrícola mediante el modelo "Mopeco"
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