Heat kernels and thermodynamics in Rindler space

We point out that using the heat kernel on a cone to compute the first quantum correction to the entropy of Rindler space does not yield the correct temperature dependence. In order to obtain the physics at arbitrary temperature one must compute the heat kernel in a geometry with different topology (without a conical singularity). This is done in two ways, which are shown to agree with computations performed by other methods. Also, we discuss the ambiguities in the regularization procedure and their physical consequences.

Singularity-free space-time

We show that the solution published in the paper by Senovilla [Phys. Rev. Lett. 64, 2219 (1990)] is geodesically complete and singularity-free. We also prove that the solution satisfies the stronger energy and causality conditions, such as global hyperbolicity, the strong energy condition, causal symmetry, and causal stability. A detailed discussion about which assumptions in the singularity theorems are not satisfied is performed, and we show explicitly that the solution is in accordance with those theorems. A brief discussion of the results is given.

Space and momentum representation analysis of Hartman's effect in wave packet transmission

The Hartman effect is analyzed in both the position and momentum representations of the problem. The importance of Wigner tunneling and deep tunneling is singled out. It is shown quantitatively how the barrier acts as a filter for low momenta (quantum speed up) as the width increases, and a detailed mechanism is proposed. Superluminal transmission is also discussed.

Approximation and support theorem for a wave equation in two space dimensions

We prove a characterization of the support of the law of the solution for a stochastic wave equation with two-dimensional space variable, driven by a noise white in time and correlated in space. The result is a consequence of an approximation theorem, in the convergence of probability, for equations obtained by smoothing the random noise. For some particular classes of coefficients, approximation in the Lp-norm for p¿1 is also proved.

Living with diabetes: quality of care and quality of life

Background: The aim of this research was to characterize the experience of living with diabetes mellitus (DM) and identify patients" opinions of the quality of care received and the results of interventions. Methods: A descriptive, exploratory evaluation study using qualitative methodology was performed. Participants consisted of 40 adult patients diagnosed with DM and followed up in a public hospital in Barcelona, Spain. A semistructured interview and a focus group were used and a thematic content analysis was performed. Results: Patients described DM as a disease that is difficult to control and that provokes lifestyle changes requiring effort and sacrifice. Insulin treatment increased the perception of disease severity. The most frequent and dreaded complication was hypoglycemia. The main problems perceived by patients affecting the quality of care were related to a disease-centered medical approach, lack of information, limited participation in decision-making, and the administrative and bureaucratic problems of the health care system. Conclusion: The bureaucratic circuits of the health care system impair patients" quality of life and perceived quality of care. Health professionals should foster patient participation in decision-making. However, this requires not only training and appropriate attitudes, but also adequate staffing and materials.

Living with diabetes: quality of care and quality of life

Background: The aim of this research was to characterize the experience of living with diabetes mellitus (DM) and identify patients" opinions of the quality of care received and the results of interventions. Methods: A descriptive, exploratory evaluation study using qualitative methodology was performed. Participants consisted of 40 adult patients diagnosed with DM and followed up in a public hospital in Barcelona, Spain. A semistructured interview and a focus group were used and a thematic content analysis was performed. Results: Patients described DM as a disease that is difficult to control and that provokes lifestyle changes requiring effort and sacrifice. Insulin treatment increased the perception of disease severity. The most frequent and dreaded complication was hypoglycemia. The main problems perceived by patients affecting the quality of care were related to a disease-centered medical approach, lack of information, limited participation in decision-making, and the administrative and bureaucratic problems of the health care system. Conclusion: The bureaucratic circuits of the health care system impair patients" quality of life and perceived quality of care. Health professionals should foster patient participation in decision-making. However, this requires not only training and appropriate attitudes, but also adequate staffing and materials.

L'ensenyament de la història i el living history

Hi ha diferents estratègies per apropar la història als escolars. La utilització de les fonts primàries (objectes, documents, etc.) esdevé una estratègia important per fer viure els temps passats. Els objectes i els documents del passat ens permeten intervenir a partir del plantejament d'enigmes i preguntes que l'alumnat pot anar resolent a partir d'una veritable recerca històrica. Una de les estratègies utilitzades en el món anglosaxó és el living history. Es tracta de "fer reviure" el passat a través de la representació de fets, estil de vida i personatges propis d'una època determinada. Aquesta estratègia s'empra en espais de presentació del patrimoni, especialment en museus i assentaments històrics i arqueològics. Dos elements són fonamentals en aquest tipus d'intervencions: la preparació del context de presentació del patrimoni i els mediadors entre la institució o espai patrimonial i els visitants. A continuació, es presenta, de manera concreta, el cas de Colonial Williamsburg, institució dels EUA pionera en la utilització d'aquesta estratègia de presentació i interpretació del patrimoni històric i arqueològic.

Space Competition and Time Delays in Human Range Expansions. Application to the Neolithic Transition

Space competition effects are well-known in many microbiological and ecological systems. Here we analyze such an effectin human populations. The Neolithic transition (change from foraging to farming) was mainly the outcome of a demographic process that spread gradually throughout Europe from the Near East. In Northern Europe, archaeological data show a slowdown on the Neolithic rate of spread that can be related to a high indigenous (Mesolithic) population density hindering the advance as a result of the space competition between the two populations. We measure this slowdown from a database of 902 Early Neolithic sites and develop a time-delayed reaction-diffusion model with space competition between Neolithic and Mesolithic populations, to predict the observed speeds. The comparison of the predicted speed with the observations and with a previous non-delayed model show that both effects, the time delay effect due to the generation lag and the space competition between populations, are crucial in order to understand the observations

Poverty and living arrangements among youth in Spain, 1980-2005

One of the most relevant demographic events in Spain from a recent historical perspective was the baby boom of the 1960s and 1970s. The “adapting to circumstances” of these generations of youth and their families through delayed emancipation and childbearing has been key in preventing a decline in their economic status. The results show that the reduction of the poverty risk among non-emancipated youth for the period 1980-2005 is explained by the fact that an increasing number of young Spaniards live with two employed parents. Thus, emancipation delay is found most in those families that can best afford it. Furthermore, the salaries of young workers remaining in the parental home have become an important factor in reducing their family poverty risk. On the other hand, fertility decline is readily explained by the economic difficulties young couples encounter in sustaining their offspring

Meta-structure correlation in protein space unveils different selection rules for folded and intrinsically disordered proteins

The number of existing protein sequences spans a very small fraction of sequence space. Natural proteins have overcome a strong negative selective pressure to avoid the formation of insoluble aggregates. Stably folded globular proteins and intrinsically disordered proteins (IDP) use alternative solutions to the aggregation problem. While in globular proteins folding minimizes the access to aggregation prone regions IDPs on average display large exposed contact areas. Here, we introduce the concept of average meta-structure correlation map to analyze sequence space. Using this novel conceptual view we show that representative ensembles of folded and ID proteins show distinct characteristics and responds differently to sequence randomization. By studying the way evolutionary constraints act on IDPs to disable a negative function (aggregation) we might gain insight into the mechanisms by which function - enabling information is encoded in IDPs.

Are we living longer but less healthy? Trends in mortality and morbidity in Catalonia (Spain), 1994-2011

Evidence on trends in prevalence of disease and disability can clarify whether countries are experiencing a compression or expansion of morbidity. An expansion of morbidity as indicated by disease have appeared in Europe and other developed regions. It is likely that better treatment, preventive measures and increases in education levels have contributed to the declines in mortality and increments in life expectancy. This paper examines whether there has been an expansion of morbidity in Catalonia (Spain). It uses trends in mortality and morbidity from major causes of death and links of these with survival to provide estimates of life expectancy with and without diseases and functioning loss. We use a repeated cross-sectional health survey carried out in 1994 and 2011 for measures of morbidity; mortality information comes from the Spanish National Statistics Institute. Our findings show that at age 65 the percentage of life with disease increased from 52% to 70% for men, and from 56% to 72% for women; the expectation of life unable to function increased from 24% to 30% for men and 40% to 47% for women between 1994 and 2011. These changes were attributable to increases in the prevalences of diseases and moderate functional limitation. Overall, we find an expansion of morbidity along the period. Increasing survival among people with diseases can lead to a higher prevalence of diseases in the older population. Higher prevalence of health problems can lead to greater pressure on the health care system and a growing burden of disease for individuals.

Nonpoint source pollution, space, time and asymetric information - a deposit refund approach

The incorporation of space allows the establishment of a more precise relationship between a contaminating input, a contaminating byproduct and emissions that reach the final receptor. However, the presence of asymmetric information impedes the implementation of the first-best policy. As a solution to this problem a site specific deposit refund system for the contaminating input and the contaminating byproduct are proposed. Moreover, the utilization of a successive optimization technique first over space and second over time enables definition of the optimal intertemporal site specific deposit refund system

Reflexiones sobre el espacio público = Thoughts on Public Space

En este artículo planteamos una aproximación a la idea de espacio público como articulador del conjunto de acontecimientos que intervienen en la vida de las ciudades. Entendemos este fenómeno como una red poliédrica y multidimensional, cuyo estudio pasa por el análisis de diversas problemáticas: la identificación de los límites entre espacio público y esfera pública; la conformación del espacio público construido; la aproximación teórica al fenómeno desde la contemporaneidad; la dimensión social del espacio público; y finalmente la perspectiva de la gestión de las ciudades. Todas estas dimensiones expresan una mirada crítica del objeto i ponen en valor niveles de trabajo interdisciplinar y multiescala, fundamentales para entender e intervenir en el espacio público de la ciudad contemporánea.

Public Art, strategies for the regeneration of public space

This paper discusses some of the key concepts in the consideration of public art as a central element in urban regeneration processes, especially in reference to its role in the processes of citizen participation.

Reflexiones sobre el espacio público = Thoughts on Public Space

En este artículo planteamos una aproximación a la idea de espacio público como articulador del conjunto de acontecimientos que intervienen en la vida de las ciudades. Entendemos este fenómeno como una red poliédrica y multidimensional, cuyo estudio pasa por el análisis de diversas problemáticas: la identificación de los límites entre espacio público y esfera pública; la conformación del espacio público construido; la aproximación teórica al fenómeno desde la contemporaneidad; la dimensión social del espacio público; y finalmente la perspectiva de la gestión de las ciudades. Todas estas dimensiones expresan una mirada crítica del objeto i ponen en valor niveles de trabajo interdisciplinar y multiescala, fundamentales para entender e intervenir en el espacio público de la ciudad contemporánea.