1,294 research outputs found
Aspectos clínicos del síndrome de Ehlers-Danlos
Se realiza una revisión bibliográfica de conjunto de los aspectos clínicos más significativos
del síndrome de Ehlers-Danlos. Se recogen datos estadísticos, características raciales,
morfotipo e interpretación patogénica actual. Se ha prestado especial atención a su comportamiento
hereditario y su fácil confusión con otras afecciones musculares o neurogénicas. Se analizan
sus síntomas más característicos, formas clínicas y complicaciones neurológicas, intestinales,
cardíacas, vasculares y cutáneas.A review of the literature concerning the most significant clinical aspects of the
Ehlers-Danlos syndrome is presented. Statistical data, race characteristics, morphotype and
current pathogenic theories are summarised. Special atention has been paid to the hereditary
behaviour and the easy misdiagnosis with other muscular and neurological entities. The usual
symptoms, clinical types, neurological, cardiac, vascular and cutaneous complications are discussed
Damageable contact between an elastic body and a rigid foundation
AbstractIn this work, the contact problem between an elastic body and a rigid obstacle is studied, including the development of material damage which results from internal compression or tension. The variational problem is formulated as a first-kind variational inequality for the displacements coupled with a parabolic partial differential equation for the damage field. The existence of a unique local weak solution is stated. Then, a fully discrete scheme is introduced using the finite element method to approximate the spatial variable and an Euler scheme to discretize the time derivatives. Error estimates are derived on the approximate solutions, from which the linear convergence of the algorithm is deduced under suitable regularity conditions. Finally, three two-dimensional numerical simulations are performed to demonstrate the accuracy and the behaviour of the scheme
Amplitude and phase representation of quantum invariants for the time dependent harmonic oscillator
The correspondence between classical and quantum invariants is established.
The Ermakov Lewis quantum invariant of the time dependent harmonic oscillator
is translated from the coordinate and momentum operators into amplitude and
phase operators. In doing so, Turski's phase operator as well as
Susskind-Glogower operators are generalized to the time dependent harmonic
oscillator case. A quantum derivation of the Manley-Rowe relations is shown as
an example
Oligodendroglioma anaplásico en el nervio óptico de un perro
Los gliomas son tumores no neuronales del tejido nervioso. En el Sistema Nervioso Central (SNC) dependiendo de su origen se clasifican en astrocitomas, oligodendrogliomas, tumores mixtos (oligoastrocitomas), ependimomas y papilomas de plexos coroideos. La retina y el nervio óptico pertenecen al SNC. Aunque las neoplasias primarias de la retina y el nervio óptico son bastante infrecuentes, son los meningiomas los tumores primarios más comunes siendo los gliomas más raros
The role of green and traditional supplier attributes on business performance
Supplier evaluation and selection are fundamental tasks since they are part of the production process and even initiate the supply chain (SC). Despite their importance in the production system, supplier evaluation and selection may be challenging activities to be performed if companies look at the wide range of available evaluation techniques and methodologies, which now seek to integrate both traditional and green attributes. In addition, companies may refuse to take into account green attributes during the supplier selection process, because they do not know their impact on commercial benefits. To overcome this limitation, this study examines the Mexican manufacturing sector and measures the impact of supplier traditional attributes and green attributes on business performance, namely production process benefits and commercial benefits. As data collection instrument, we administered a survey to 253 supplier evaluators and selectors; then, using the gathered data, we constructed a structural equation model. The model includes four variables to determine the impact of traditional and green attributes on business performance: green attributes, traditional attributes, production process benefits, and commercial benefits. The results indicate that all the latent variables have positive direct effects on one another. For instance, process benefits show the largest effects on commercial benefits, but the most significant effect is caused by traditional attributes on commercial benefits through green attributes and production process benefits. © 2017 by the authors
Depositional style and tectonostratigraphic evolution of the El Bierzo Tertiary Subbasin (Pyrenean orogen, NW Spain)
El Bierzo Tertiary sub-basin (Oligocene–Miocene, NW Spain) is a small remnant of the western Duero Basin, a nonmarine broken foreland basin developed in front of the Cantabrian Mountains (Pyrenean orogen). The alluvial infill of El Bierzo Tertiary sub-basin consists of a coarsening-upward succession from fluvial (Toral Formation) to alluvial-fan deposits (Las Médulas Formation) and reflects the uplift of the Cantabrian Mountains, in the north, and then of the related Galaico-Leoneses Mountains, in the south. These alluvial deposits show signs of having been laid down mainly by catastrophic flows (flood-dominated systems) and consist of three main depositional elements, namely, flood-plain fines, and lobe and channel conglomerates and sandstones. The vertical stacking patterns of these deposits and their relationships to the Alpine structures permit to unravel the tectonosedimentary evolution of the basin. The alluvial-plain element is the main constituent of a wide unconfined alluvial plain (Toral Formation) during the early stages of basin evolution, whereas the channel and lobe elements form a set of relatively small, laterally confined alluvial fans (Las Médulas Formation) fed first from the north and then from the south. Las Médulas deposits form two superposed units, the lower unit, cut by the Alpine thrusts, shows a progradational character, and the upper unit, which postdates most of the thrusts but not the youngest ones, displays a composite retrogradational trend. This organisation reflects the interplay between thrust emplacement and alluvial-fan sedimentation and suggests that maximum progradation took place during the climax of Alpine deformation
Assessing job performance using brief self-report scales: The case of the individual work performance questionnaire
Job performance is considered the “ultimate dependent variable” in human resource management, turning its assessment into a capital issue. The present study analyzes the functioning of a brief 18-item self-report scale, the Individual Work Performance Questionnaire (IWPQ), which measures the main dimensions of job performance (task performance, contextual performance, and counterproductive behaviors) in a wide variety of jobs. Participants were 368 employees who voluntarily answered a questionnaire including the IWPQ, other performance scales, and the NEO-FFI. Descriptive statistics, exploratory structural equation modeling, and correlations were performed. Results show that the IWPQ has a tridimensional structure with adequate reliability, exhibits significant associations with other measures of performance, and its association with personality traits is similar in terms of direction and strength of the correlations between other job performance measures and personality. We conclude that the IWPQ is an adequate measure of job performance but with emphasis on behaviors aimed toward organizations.
El desempeño laboral es considerado la “variable dependiente definitiva” en recursos humanos, convirtiendo su evaluación en algo crucial. El presente estudio analiza el funcionamiento de una escala autoinformada breve de 18 ítems, el Individual Work Performance Questionnaire (IWPQ), que mide las principales dimensiones del desempeño laboral (desempeño de tarea, desempeño contextual y comportamientos contraproductivos en el trabajo) en una amplia variedad de trabajos. Los participantes fueron 368 empleados que voluntariamente completaron un cuestionario que incluía el IWPQ, otras escalas de desempeño y el NEO-FFI. Se llevaron a cabo estadísticos descriptivos, modelos exploratorios de ecuaciones estructurales y correlaciones. Los resultados muestran que el IWPQ tiene una estructura tridimensional con una fiabilidad adecuada, mostrando asociaciones significativas con el resto de medidas de desempeño. En cuanto a los factores de personalidad, el IWPQ muestra correlaciones similares a las de los otros instrumentos de desempeño analizados. Se concluye que el IWPQ es un instrumento adecuado para medir de manera breve y autoinformada el desempeño laboral, pero con énfasis en los comportamientos dirigidos hacia la organización
Do young dating app users and non-users differ in mating orientations?
In recent years, dating apps have changed the way people meet and communicate with potential romantic and/or sexual partners. There exists a stereotype considering that these apps are used only for casual sex, so those apps would not be an adequate resource to find a long-term relationship. The objective of this study was to analyze possible individual differences in the mating orientations (short-term vs. long-term) between users and non-users of dating apps. Participants were 902 single students from a mid-size Spanish university, of both sexes (63% female, and 37% male), aged between 18 and 26 years (M = 20.34, SD = 2.05), who completed a battery of online questionnaires. It was found that, whereas dating apps users had a higher short-term mating orientation than non-users (more frequent behavior, higher desire, and more positive attitude), there were no differences in the long-term orientation as a function of use/non-use. Considering this, dating apps are a resource with a strong presence of people interested on hooking-up while, simultaneously, not a bad (nor good) option for finding long-term love
Graph Creation, Visualisation and Transformation
We describe a tool to create, edit, visualise and compute with interaction
nets - a form of graph rewriting systems. The editor, called GraphPaper, allows
users to create and edit graphs and their transformation rules using an
intuitive user interface. The editor uses the functionalities of the TULIP
system, which gives us access to a wealth of visualisation algorithms.
Interaction nets are not only a formalism for the specification of graphs, but
also a rewrite-based computation model. We discuss graph rewriting strategies
and a language to express them in order to perform strategic interaction net
rewriting
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