878 resultados para History of mathematics in Spain


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Identifying the immunologic and virologic consequences of discontinuing antiretroviral therapy in HIV-infected patients is of major importance in developing long-term treatment strategies for patients with HIV-1 infection. We designed a trial to characterize these parameters after interruption of highly active antiretroviral therapy (HAART) in patients who had maintained prolonged viral suppression on antiretroviral drugs. Eighteen patients with CD4+ T cell counts ≥ 350 cells/μl and viral load below the limits of detection for ≥1 year while on HAART were enrolled prospectively in a trial in which HAART was discontinued. Twelve of these patients had received prior IL-2 therapy and had low frequencies of resting, latently infected CD4 cells. Viral load relapse to >50 copies/ml occurred in all 18 patients independent of prior IL-2 treatment, beginning most commonly during weeks 2–3 after cessation of HAART. The mean relapse rate constant was 0.45 (0.20 log10 copies) day−1, which was very similar to the mean viral clearance rate constant after drug resumption of 0.35 (0.15 log10 copies) day−1 (P = 0.28). One patient experienced a relapse delay to week 7. All patients except one experienced a relapse burden to >5,000 RNA copies/ml. Ex vivo labeling with BrdUrd showed that CD4 and CD8 cell turnover increased after withdrawal of HAART and correlated with viral load whereas lymphocyte turnover decreased after reinitiation of drug treatment. Virologic relapse occurs rapidly in patients who discontinue suppressive drug therapy, even in patients with a markedly diminished pool of resting, latently infected CD4+ T cells.

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The lacustrine deposits infilling the intramontane Guadix-Baza Basin, in the Betic Range of Southern Spain, have yielded abundant well-preserved lithic artifacts. In addition, the lake beds contain a wide range of micromammals including Mimomys savini and Allophaiomys burgondiae and large mammals such as Mammuthus and Hippopotamus together with the African saber-toothed felid Megantereon. The association of the lithic artifacts along with the fossil assemblages, themselves of prime significance in the Eurasian mammal biochronology, is providing new insight into the controversy of the human settlement in Southern Europe. Despite the importance of the artifacts and fossil assemblage, estimates of the geological age of the site are still in conflict. Some attempts at dating the sediments have included biochronology, uranium series, amino acid racemization, and stratigraphic correlation with other well-dated sections in the basin, but so far have failed to yield unambiguous ages. Here we present paleomagnetic age dating at the relevant localities and thus provide useful age constraints for this critical paleoanthropological and mammal site. Our data provide firm evidence for human occupation in Southern Europe in the Lower Pleistocene, around 1 mega-annum ago. The current view of when and how hominids first dispersed into Europe needs to be reevaluated.

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This paper argues that historical works in pharmacy are important tools for the clinician as well as the historian. With this as its operative premise, delineating the tripartite aspects of pharmacy as a business enterprise, a science, and a profession provides a conceptual framework for primary and secondary resource collecting. A brief history and guide to those materials most essential to a historical collection in pharmacy follows. Issues such as availability and cost are discussed and summarized in checklist form. In addition, a glossary of important terms is provided as well as a list of all the major U.S. dispensatories and their various editions. This paper is intended to serve as a resource for those interested in collecting historical materials in pharmacy and pharmaco-therapeutics as well as provide a history that gives context to these classics in the field. This should provide a rationale for selective retrospective collection development in pharmacy.

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This paper presents a brief survey of the idea of symmetry in mathematics, as exemplified by some particular developments in algebra, differential equations, topology, and number theory.

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We present the results of the analysis of satellite imagery to study light pollution in Spain. Both calibrated and non-calibrated DMSP-OLS images were used. We describe the method to scale the non-calibrated DMSP-OLS images which allows us to use differential photometry techniques in order to study the evolution of the light pollution. Population data and DMSP-OLS satellite calibrated images for the year 2006 were compared to test the reliability of official statistics in public lighting consumption. We found a relationship between the population and the energy consumption which is valid for several regions. Finally the true evolution of the electricity consumption for street lighting in Spain from 1992 to 2010 was derived; it has been doubled in the last 18 years in most of the provinces. (C) 2013 Elsevier Ltd. All rights reserved,

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BACKGROUND: Household service work has been largely absent from occupational health studies. We examine the occupational hazards and health effects identified by immigrant women household service workers. METHODS: Exploratory, descriptive study of 46 documented and undocumented immigrant women in household services in Spain, using a phenomenological approach. Data were collected between September 2006 and May 2007 through focus groups and semi-structured individual interviews. Data were separated for analysis by documentation status and sorted using a mixed-generation process. In a second phase of analysis, data on psychosocial hazards were organized using the Copenhagen Psychosocial Questionnaire as a guide. RESULTS: Informants reported a number of environmental, ergonomic and psychosocial hazards and corresponding health effects. Psychosocial hazards were especially strongly present in data. Data on reported hazards were similar by documentation status and varied by several emerging categories: whether participants were primarily cleaners or carers and whether they lived in or outside of the homes of their employers. Documentation status was relevant in terms of empowerment and bargaining, but did not appear to influence work tasks or exposure to hazards directly. CONCLUSIONS: Female immigrant household service workers are exposed to a variety of health hazards that could be acted upon by improved legislation, enforcement, and preventive workplace measures, which are discussed.

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The aim of this article is to highlight the importance of the history of public health for public health research and practice itself. After summarily reviewing the current great vitality of the history of collective health oriented initiatives, we explain three particular features of the historical vantage point in public health, namely the importance of the context, the relevance of a diachronic attitude and the critical perspective. In order to illustrate those three topics, we bring up examples taken from three centuries of fight against malaria, the so called “re-emerging diseases” and the 1918 influenza epidemic. The historical approach enriches our critical perception of the social effects of initiatives undertaken in the name of public health, shows the shortcomings of public health interventions based on single factors and asks for a wider time scope in the assessment of current problems. The use of a historical perspective to examine the plurality of determinants in any particular health condition will help to solve the longlasting debate on the primacy of individual versus population factors, which has been particularly intense in recent times.

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Tourism is the main economic activity in many towns in the province of Alicante in southeast Spain and has turned this area into a paradigmatic example of mass tourism on the Mediterranean coast. Since the 1960s, the province's coastal towns have opted for a development model centred on what is known as 'residential tourism' or 'second-home tourism', with few exceptions, such as Benidorm. We wish to put forward the argument that the main social agents in the tourism sector have not perceived the 'search for authenticity' as a factor that may attract tourists to this area. To this end, we will start by reviewing critically the theoretical discourse about the role played by authenticity in the motivation of tourists. Then we will discuss some of the results obtained from empirical, qualitative research that included 37 in-depth interviews. As a guide for our empirical research, we use a model based on the stakeholder theory. The epistemological difficulties faced by researchers do not justify certain critical arguments that try to highlight the impossibility of operationalising essential concepts and approaches such as that of authenticity. Therefore, it is necessary that empirical research continues to delve into the sociological keys that determine the 'search for authenticity' in the tourists' experience.

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Differential SAR Interferometry (DInSAR) is a remote sensing method with the well demonstrated ability to monitor geological hazards like earthquakes, landslides and subsidence. Among all these hazards, subsidence involves the settlement of the ground surface affecting wide areas. Frequently, subsidence is induced by overexploitation of aquifers and constitutes a common problem that affects developed societies. The excessive pumping of underground water decreases the piezometric level in the subsoil and, as a consequence, increases the effective stresses with depth causing a consolidation of the soil column. This consolidation originates a settlement of ground surface that must be withstood by civil structures built on these areas. In this paper we make use of an advanced DInSAR approach - the Coherent Pixels Technique (CPT) [1] - to monitor subsidence induced by aquifer overexploitation in the Vega Media of the Segura River (SE Spain) from 1993 to the present. 28 ERS-1/2 scenes covering a time interval of about 10 years were used to study this phenomenon. The deformation map retrieved with CPT technique shows settlements of up to 80 mm at some points of the studied zone. These values agree with data obtained by means of borehole extensometers, but not with the distribution of damaged buildings, well points and basements, because the occurrence of damages also depends on the structural quality of the buildings and their foundations. The most interesting relationship observed is the one existing between piezometric changes, settlement evolution and local geology. Three main patterns of ground surface and piezometric level behaviour have been distinguished for the study zone during this period: 1) areas where deformation occurs while ground conditions remain altered (recent deformable sediments), 2) areas with no deformation (old and non-deformable materials), and 3) areas where ground deformation mimics piezometric level changes (expansive soils). The temporal relationship between deformation patterns and soil characteristics has been analysed in this work, showing a delay between them. Moreover, this technique has allowed the measurement of ground subsidence for a period (1993-1995) where no instrument information was available.

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Paper submitted to the 44th European Congress of the European Regional Science Association, Porto, 25-29 August 2004.