953 resultados para 1209 Estadística


Relevância:

10.00% 10.00%

Publicador:

Resumo:

El litoral de Alicante ha sufrido grandes transformaciones territoriales desde las décadas de 1960 y 1970 a raíz de la actividad turística. Uno de los servicios que necesita esta actividad, entre otros, es el abastecimiento de agua potable. En este sentido, por su papel estratégico, el suministro de agua en alta es decisivo para abastecer a los municipios turístico-residenciales. El objetivo de este estudio es conocer y analizar los diferentes sistemas de abastecimiento de agua en alta en la costa de Alicante, sus características, infraestructuras, recursos hídricos disponibles y medidas de gestión llevados a cabo. Algunas de las conclusiones extraídas son el papel estratégico que ejercen en el territorio, especialmente con el agua, un recurso escaso y de vital importancia para la orla costera alicantina, sobre todo en los meses estivales.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Restriction fragment length polymorphism (RFLP) analysis of chloroplast (cp) DNA is a powerful tool for the study of microevolutionary processes in land plants, yet has not previously been applied to seaweed populations. We used cpDNA-RFLP, detected on Southern blots using labeled total plastid DNA, to search for intraspecific and intrapopulational cpDNA RFLP polymorphism in two species of the common red algal genus Ceramium in Ireland and Britain. In C. botryocarpum one polymorphism was detected in one individual among 18 from two populations. Twenty-six individuals of C. virgatum from five populations at three locations exhibited a total of four haplotypes. One was frequent (80.8% of individuals); the others were rare (7.7, 7.7 and 4.2%) and were private to particular populations. Polymorphism was observed in two populations. The corrected mean was 2.26 +/- 0.36 haplotypes per population, which was within the typical range determined for higher plants using similar techniques. The spatial distribution of haplotypes was heterogeneous, with highly significant population differentiation (P = 0.00018; Fisher's exact test). Intraspecific polymorphism in C. virgatum had no impact on species-level phylogenetic reconstruction. This is the first unequivocal report of both intraspecific and intrapopulational cpDNA-RFLP polymorphism in algae.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Diagnostic-based modeling (DBM) actively combines complementary advantages of numerical plasma simulations and relatively simple optical emission spectroscopy (OES). DBM is applied to determine spatial absolute atomic oxygen ground-state density profiles in a micro atmospheric-pressure plasma jet operated in He–O2. A 1D fluid model with semi-kinetic treatment of the electrons yields detailed information on the electron dynamics and the corresponding spatio-temporal electron energy distribution function. Benchmarking this time- and space-resolved simulation with phase-resolved OES (PROES) allows subsequent derivation of effective excitation rates as the basis for DBM. The population dynamics of the upper O(3p3P) oxygen state (? = 844 nm) is governed by direct electron impact excitation, dissociative excitation, radiation losses, and collisional induced quenching. Absolute values for atomic oxygen densities are obtained through tracer comparison with the upper Ar(2p1) state (? = 750.4 nm). The resulting spatial profile for the absolute atomic oxygen density shows an excellent quantitative agreement to a density profile obtained by two-photon absorption laser-induced fluorescence spectroscopy.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Objective: This Student Selected Component (SSC) was designed to equip United Kingdom (UK) medical students to engage in whole-person care. The aim was to explore students' reactions to experiences provided, and consider potential benefits for future clinical practice.

Methods: The SSC was delivered in the workplace. Active learning was encouraged through facilitated discussion with and observation of clinicians, the palliative team, counselling services, hospital chaplaincy and healing ministries; sharing of medical histories by patients; and training in therapeutic communication. Assessment involved reflective journals, literature appraisal, and role-play simulation of the doctor-patient consultation. Module impact was evaluated by analysis of student coursework and a questionnaire.

Results: Students agreed that the content was stimulating, relevant, and enjoyable and that learning outcomes were achieved. They reported greater awareness of the benefit of clinicians engaging in care of the "whole person" rather than "the disease." Contributions of other professions to the healing process were acknowledged, and students felt better equipped for discussion of spiritual issues with patients. Many identified examples of activities which could be incorporated into core teaching to benefit all medical students.

Conclusion: The SSC provided relevant active learning opportunities for medical students to receive training in a whole-person approach to patient care.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We analyze the effect of a quantum error correcting code on the entanglement of encoded logical qubits in the presence of a dephasing interaction with a correlated environment. Such correlated reservoir introduces entanglement between physical qubits. We show that for short times the quantum error correction interprets such entanglement as errors and suppresses it. However, for longer time, although quantum error correction is no longer able to correct errors, it enhances the rate of entanglement production due to the interaction with the environment.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The generation of entanglement between two oscillators that interact via a common reservoir is theoretically studied. The reservoir is modeled by a one-dimensional harmonic crystal initially in thermal equilibrium. Starting from a separable state, the oscillators can become entangled after a transient time, that is of the order of the thermalization time scale. This behaviour is observed at finite temperature even when the oscillators are at a distance significantly larger than the crystal's interparticle spacing. The underlying physical mechanisms can be explained by the dynamical properties of the collective variables of the two oscillators which may decouple from or be squeezed by the reservoir. Our predictions can be tested with an ion chain in a linear Paul trap. Copyright (C) EPLA, 2011

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In previous experiments suggesting that previewing visual landscapes speeds homing from familiar release sites, restricted access to olfactory cues may have artefactually encouraged homing pigeons, Calumba livia, to resort to visual landmark orientation. Since evidence for the role of visual landmarks in wide-ranging avian orientation is still equivocal, Braithwaite & Guilford's (1991, Proc. R. Sec. Lond. Ser. B, 245, 183-186) 'previewing' experiments were replicated: birds were allowed or denied visual access to a familiar site prior to release, but allowed ample access to olfactory cues. In experiment 1, allowing birds to preview familiar sites for 5 min prior to release enhanced homing speeds by about 12%. In experiment 2, modified to reduce between-day effects on variation, previewing enhanced homing speeds by about 16%. These experiments support the conclusion that visual landmarks remote from sight of the loft are an important component of the familiar area map, although the nature of the landmarks and how they are encoded remain to be determined. (C) 1997 The Association for the Study of Animal Behaviour.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

When a collection of phenotypically diverse organisms compete with each other for limited resources, the population can evolve into tightly localised clusters. Past studies have neglected the effects of demographic noise and studied the population on a macroscopic scale, where cluster formation is found to depend on the shape of the curve describing the decline of competition strength with phenotypic distance. Here we show how including the effects of demographic noise leads to a radically different conclusion. Two situations are identified: a weak-noise regime in which the population exhibits patterns of fluctuation around the macroscopic description, and a strong-noise regime where clusters appear spontaneously even in the case that all organisms have equal fitness. editor's choice Copyright (C) EPLA, 2012

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Gas adsorption experiments have been carried out on a copper benzene tricarboxylate metal-organic framework material, HKUST-1. Hydrogen adsorption at 1 and 10 bar (both 77 K) gives an adsorption capacity of 11.16 mmol H-2 per g of HKUST-1 (22.7 mg g(-1), 2.27 wt %) at 1 bar and 18 mmol per g (36.28 mg g(-1), 3.6 wt %) at 10 bar. Adsorption of D-2 at 1 bar (77 K) is between 1.09 (at 1 bar) and 1.20(at < 100 mbar) times the H-2 values depending on the pressure, agreeing with the theoretical expectations. Gravimetric adsorption measurements of NO on HKUST-1 at 196 K (1 bar) gives a large adsorption capacity of similar to 9 mmol g(-1), which is significantly greater than any other adsorption capacity reported on a porous solid. At 298 K the adsorption capacity at 1 bar is just over 3 mmol g(-1). Infra red experiments show that the NO binds to the empty copper metal sites in HKUST-1. Chemiluminescence and platelet aggregometry experiments indicate that the amount of NO recovered on exposure of the resulting complex to water is enough to be biologically active, completely inhibiting platelet aggregation in platelet rich plasma.