365 research outputs found
Una Estimación Del Consumo De Madera En España Entre 1860 Y 1935
The main objective of this paper is to contribute a continuous annual series of timber consumption in Spain for the period 1860-1935, an unexplored topic in Spanish economic history. Then the paper estimates a standard consumption function trying to explain the behavior of the serie. The main conclusion is that Spanish timber consumption had a positive GDP elasticity (0,47) with a growth in both traditional and new utilities of timber, regardles of the evolution of the prices of the product. This suggests that the economic growth of the period was not only based on new technologies and new raw materials, but also on a growing use of an organic and traditional product like timber.timber, comsumption function
Not Only Subterranean Forests: Wood Consumption And Economic Development In Britain (1850-1938)
The essential aim of this paper is to analyze wood consumption in Great Britain over the period 1850-1938. We calculate the apparent consumption of wood in Britain, taking into account both net imports of wood and the home harvest of wood. Then we develop some quantitative exercises which correlate wood consumption with GDP, and with prices of wood and iron (as an alternative material to wood). The main conclusion is that, although wood had lost its economic centrality after the energetic transition, wood consumption continued to grow in Britain both in absolute and relative terms, showing a positive elasticity to GDP superior to the unity. The decline of wood prices in the long run, the innovations affecting wood exploitation and treatment, and the fact that wood was used in a wide range of economic activities, can explain that growth in consumption. Britain faced the increase in wood demand relying almost totally on imports. Thus, although British economic development was to a great extent focussed on what has been called the “subterranean forests” of coal, simultaneously supported large tracts of foreign forest.wood, forest history, industrialization, consumption function
Business Networks and Social Capital in Basque Industrialization (1886–1925)
The aim of this article is to analyse the potential role that social capital played in the industrialization of the Basque Country. The province of Gipuzkoa, together with the neighbouring Bizkaia (Biscay), was one of the most dynamic provinces in Spain in terms of the creation of companies. Using information obtained from the registration of new companies in the Mercantile Register, and through social network analysis, we try to measure the importance that social capital may have had in this process. The methodology is tested with the case study of the arms industry in Eibar, one of the most important sectors in the region.
Reduction of the transverse effective charge of optical phonons in ZnO under pressure
This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 96, 231906 (2010) and may be found at https://doi.org/10.1063/1.3447798."From Raman scattering on a-plane wurtzite ZnO crystals we obtained a decreasing splitting between longitudinal and transversal optical phonons with A1 and E1 symmetry as a function of hydrostatic pressure up to 5.5 GPa. Consequently, the transverse effective charge (e∗T) exhibits a strong reduction with increasing pressure, yielding 2.17–14.6×10−3 P/GPa and 2.04–13.7×10−3 P/GPa (in units of the elementary charge) for the A1 and E1 phonons, respectively. We find a clear systematic in the linear pressure coefficient of e∗T with bond polarity for the series of wide-band gap semiconductors SiC, AlN, GaN, and ZnO.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, Bauelement
Prospección de poblaciones de macrófitos acuáticos amenazados: el ejemplo de Potamogeton praelongus
Contrasting intrainterstadial climatic evolution between high and middle North Atlantic latitudes: A close-up of Greenland Interstadials 8 and 12
Three highly resolved pollen and sea surface temperature records from the Iberian margin (36â "42°N) reveal the local evolution of vegetation and climate associated with the rapid climatic variability of marine isotope stage 3. The comparison of the climate at these midlatitudes with δD and d excess from Greenland ice cores shows that the northâ south climatic gradient underwent strong variations during the long Greenland Interstadials (GIs) 8 and 12. After the Northern Hemispheric rapid warming at the Greenland Stadial (GS)â GI transition, the trend during the first part of the GI is a Greenland cooling and an Iberian warming. This increase of the North Atlantic climatic gradient led to moisture transportation to Greenland from midlatitudes (lightest d excess) and to a drying episode in Iberia. The subsequent temperature decrease in Greenland and Iberia associated with the precipitation increase in the latter region occurred when the major source of Greenland precipitation shifted to lower latitudes (d excess increase)
Intake of Nutrient and Non-Nutrient Dietary Antioxidants. Contribution of Macromolecular Antioxidant Polyphenols in an Elderly Mediterranean Population
The intake of antioxidants in the diet is a useful parameter to estimate the potential of diet to prevent chronic diseases associated with oxidative stress and ageing. The objective was to estimate the intake of nutrient and non nutrient antioxidants associated with the dietary fiber matrix in a healthy and functionally independent population aged over 80, estimating the intake of antioxidant nutrients and including soluble low molecular weight and macromolecular polyphenols in the non-nutrient antioxidant group. Specific nutrients related to oxidative stress (copper, zinc, selenium, manganese, vitamins A, C and E) were ingested in optimal quantities according to reference values. Total intake of non-nutrient antioxidants was 2196 mg/person/day, and macromolecular polyphenols were found to be the main dietary antioxidants, contributing 71% to the total intake of phenolic compounds. The intake, metabolism and physiological effects of all nutrient and non-nutrient dietary antioxidants must therefore be taken into account when evaluating their health benefits
Programa de Educación para la detección precoz del cáncer testicular en adolescentes.
Introducción: El cáncer de testículo es el tumor más frecuente en varones de entre 20 y 34 años. La detección temprana de esta patología supone una disminución de la morbimortalidad a consecuencia de la enfermedad y su tratamiento; lo que otorga una importancia destacada a la autoexploración testicular como primera medida de detección precoz. Pocos son los varones que aseguran realizar un autoexamen testicular periódicamente, bien por falta de concienciación, o por desconocimiento del procedimiento para realizarlo. Objetivos: Desarrollar un Programa de Salud dirigido a adolescentes de 4ºESO para aumentar los conocimientos sobre la autoexploración testicular, concienciación del cáncer de testículo, y la detección precoz. Metodología: Se ha realizado una búsqueda bibliográfica sobre el cáncer de testículo y las formas de detección, haciendo énfasis en la autoexploración testicular como forma de detección precoz. Posteriormente se ha desarrollado un Programa de Salud, seleccionando un grupo de adolescentes de 4ºESO para llevarlo a cabo. Conclusiones: La falta de información sobre el cáncer de testículo, y el déficit de conocimiento sobre la autoexploración testicular constituyen la causa principal de la no realización de autoexamen en los varones jóvenes; por lo que deben desarrollarse programas de educación para esta población, dirigidos a la concienciación y formación en el tema. Palabras clave: “cáncer testicular”, “autoexploración”, “prevención”, “programa de salud”
Design of nanostructured siloxane-gelatin coatings: Immobilization strategies and dissolution properties
Owing to the outstanding service life of metallic prostheses, a substantial effort has been put into their surface modification to improve biocompatibility and reduce metallic ion diffusion. To satisfy these requirements, the coating materials obtained using the sol-gel method, with its wide range of tuning properties, have been extensively explored. The well-known biocompatibility of these materials makes them good candidates for different biomedical applications. We designed a series of siloxane-gelatin hybrids to be used as coatings for metallic implants or in controlled delivery systems. Two different matrixes were designed based on methyltrimethoxysilane (MTMOS), tetraethoxysilane (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) alkoxysilane precursors. In one hybrid coating gelatin was physically entrapped and in the other it was linked to the siloxane network by covalent bonds. Synthesis parameters were established by studying the sol-gel reaction using 29Si nuclear magnetic resonance (29Si NMR), which also allowed quantification of the network connectivity. Dissolution and degradation studies showed the effectiveness of GPTMS as a covalent coupling agent between the silica and gelatin phases; it increased the stability of the coatings in aqueous media. The aim of this study was to design a set of hybrid materials with highly tailorable properties, suitable for their potential biomedical application
Estudio sobre el efecto de la secuenciación neurodinámica en el test del nervio mediano en sujetos asintomáticos
Introducción: Los test neurodinámicos llevan a cabo una serie de movimientos corporales que producen acontecimientos mecánicos y fisiológicos en el sistema nervioso. El orden de los movimientos podría influir en las respuestas. Se desconoce el mecanismo subyacente más relevante por lo que existe necesidad de mayor investigación sobre la secuenciación neurodinámica en poblaciones asintomáticas, de tal manera que los signos en la clínica puedan interpretarse con respecto a hallazgos normales.Objetivos: Analizar el efecto de la secuenciación neurodinámica en el test del nervio mediano en sujetos asintomáticos para las variables rango de movimiento articular, localización, intensidad y calidad de los síntomas.Metodología: La muestra final la formaron 32 voluntarios asintomáticos (64 casos). Un evaluador llevó a cabo las secuencias próximo-distal y disto-proximal en el test del nervio mediano y otro examinador colocó el goniómetro para recoger el rango de movimiento articular. Se registró la localización (mapa corporal), intensidad (EVA) y calidad de los síntomas (descriptores).Resultados: Se obtuvieron diferencias estadísticamente significativas en los rangos de movimiento al comparar ambas secuencias (pConclusión: Los resultados parecen indicar que el orden de los movimientos del test neurodinámico para el nervio mediano en sujetos asintomáticos, influye en el rango de movimiento articular alcanzado. Las variables calidad e intensidad de los síntomas no mostraron diferencias entre secuencias.<br /
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