122 research outputs found

    Contribución al conocimiento de crustáceos y rotíferos del Delta del Ebro

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    Hydrologic and landscape changes in the Middle Ebro River (NE Spain): implications for restoration and management

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    The changes of landscape (1927–2003), discharge regime and anthropic activities with the river-floodplain of one reach at the Middle Ebro River (NE Spain) were investigated with the objective to identify the factors that best explain the natural ecotope succession and propose a realistic restoration option with consideration of the landscape dynamics during the last century and the socio-economic context. Our results indicate that hydrological and landscape patterns have been dramatically changed during the last century as a consequence of human alteration of the fluvial dynamics within the studied reach. The magnitude and variability of river discharge events have decreased at the end of the last century, and flood protection structures have disrupted the river floodplain connectivity. As a result, the succesional pathways of riparian ecotopes have been heavily modified because natural rejuvenation no longer takes place, resulting in decreased landscape diversity. It is apparent from these data that floodplain restoration must be incorporated as a significant factor into river management plans if a more natural functioning wants to be retrieved. The ecotope structure and dynamics of the 1927–1957 period should be adopted as the guiding image, whereas current hydrologic and landscape (dykes, raised surfaces) patterns should be considered. Under the current socio-economic context, the more realistic option seems to create a dynamic river corridor reallocating dykes and lowering floodplain heights. The extent of this river corridor should adapt to the restored flow regime, although periodic economic investments could be an option if the desired self-sustained dynamism is not reached

    Síndrome de boca ardiente: estudio retrospectivo de 140 casos en una muestra de la población catalana

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    En este trabajo se presentan los resultados del análisis de factores etiológicos y clínicos y su relación con el síndrome de la boca ardiente (SBA) en una muestra de la población catalana (Barcelona, España). El objetivo del presente estudio es establecer las relaciones entre el síndrome de boca ardiente (SBA) y las siguientes variables: edad, sexo, depresión, depresión enmascarada, cancerofobia, sensación de boca seca, sensación de cuerpo extraño y quemazón, contribuyendo, así, al estudio epidemiológico de esta enfermedad en Cataluña. Se estudian 140 historias clínicas de pacientes diagnosticados con la enfermedad y 140 historias clínicas de pacientes control. Los datos fueron analizados estadísticamente para examinar las relaciones y frecuencias de las variables y la enfermedad. Los resultados obtenidos servirán para entender mejor las posibles relaciones de los factores etiológicos y clínicos estudiados con la enfermedad, así como el desarrollo del SBA y sus implicaciones en la población catalana.The results of analyzing etiologic and clinical factors, and their connection with the burning mouth syndrome (BMS) in a sample of Catalan (Barcelona, Spain) population are presented in this work. The purpose of this study is to establish connections between BMS and the following variables: age, sex, overt depression, masked depression, cancerophobia, dry mouth, foreign body sensation in the mouth, and burning. 140 clinical cases of patients diagnosed with the disease and 140 cases of control patients are studied here. The data were statistically analyzed to study connections as well as the disease and variables frequency. The obtained results will help understanding possible connections of the studied etiologic and clinical factors with the disease, as well as the course of BMS, and its consequences in the Catalan population

    Nurse species could facilitate the recruitment of mangrove seedlings after hydrological rehabilitation

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    Changes in hydrology are one of the main causes of mangrove degradation; however, the reforestation of mangrove has been the main restoration activity and very little information on how pioneer species can facilitate the colonization and development of the mangrove species is available. After carrying out a water reconnection as the sole restoration action, secondary succession has occurred in the mangrove rehabilitation area of Celestun (Yucatan, SE Mexico). Two pioneer species, Batis maritima and Salicornia virginica were observed in plots with different coverage (0%, 20%, 100%) where the three natural mangrove species were established, with Laguncularia racemosa as the dominant species in density. The greatest interstitial mean salinity (79.9 g/kg) was recorded in the plots with 20% cover, while the lowest salinity (40.7 g/kg) was recorded in the plots with 100% of coverage. At the end of sampling period nutrient content (carbon, nitrogen and phosphorus) and organic matter in the sediment were greatest in the plots with 100% cover, whereas the lowest concentrations were observed in the site devoid of vegetation. The percentage cover of S. virginica and B. maritima changed over time; in the plot that started with 100% cover it decreased until it disappeared at the end of the study period, whereas it increased in the plots with 20% and 0% cover. This study shows that B. maritima and S. virginica has a function as "facilitator species" initially colonizing the bare soil and modifying its conditions (decreasing interstitial salinity and increasing nutrient), which favored colonization and growing of mangrove seedlings

    From national monopoly to Multinational Corporation: how regulation shaped the road towards telecommunications internationalization

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    One of the consequences of major regulatory reform of the telecommunications sector from the end of the 1970s – particularly, privatization, liberalization and deregulation – was the establishment of a new business environment which permitted former national telecommunications monopolies to expand abroad. From the 1990s, a number of these firms, particularly those based in Europe, joined the rankings of the world’s leading Multinational Corporations. Their internationalization was uneven, however: while some firms internationalised strongly, others ventured abroad much slower. This article explores how the regulatory framework within which telecommunications incumbents evolved over the long-term shaped their subsequent, uneven, paths to internationalization. Two case studies representing ´maximum variation´ are selected: Telefónica, whose early and unrelenting expansion transformed it into one of the world’s most international of Multinational Corporations, and BT, whose overseas ventures failed and, with eroding domestic market share, forced the firm to partially retreat, becoming the least international of the large European incumbents. Long-term ownership, access to capital, management style and exposure to liberalization strongly influenced firms’ approaches to internationalizatio

    Seven-year mortality in heart failure patients with undiagnosed diabetes : an observational study

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    Background: Patients with type 2 diabetes mellitus and heart failure have adverse clinical outcomes, but the characteristics and prognosis of those with undiagnosed diabetes in this setting has not been established. Methods: In total, 400 patients admitted consecutively with acute heart failure were grouped in three glycaemic categories: no diabetes, clinical diabetes (previously reported or with hypoglycaemic treatment) and undiagnosed diabetes. The latter was defined by the presence of at least two measurements of fasting plasma glycaemia ≥ 7 mmol/L before or after the acute episode.Group differences were tested by proportional hazards models in all-cause and cardiovascular mortality during a 7-year follow-up. Results: There were 188 (47%) patients without diabetes, 149 (37%) with clinical diabetes and 63 (16%) with undiagnosed diabetes. Patients with undiagnosed diabetes had a lower prevalence of hypertension, dyslipidaemia, peripheral vascular disease and previous myocardial infarction than those with clinical diabetes and similar to that of those without diabetes. The adjusted hazards ratios for 7-year total and cardiovascular mortality compared with the group of subjects without diabetes were 1.69 (95% CI: 1.17-2.46) and 2.45 (95% CI: 1.58-3.81) for those with undiagnosed diabetes, and 1.48 (95% CI: 1.10-1.99) and 2.01 (95% CI: 1.40-2.89) for those with clinical diabetes. Conclusions: Undiagnosed diabetes is common in patients requiring hospitalization for acute heart failure. Patients with undiagnosed diabetes, despite having a lower cardiovascular risk profile than those with clinical diabetes, show a similar increased mortality

    Repetitive levosimendan infusions for patients with advanced chronic heart failure in the vulnerable post-discharge period

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    Hospitalization for acute heart failure (HF) is associated with a substantial morbidity burden and with associated healthcare costs and an increased mortality risk. However, few if any major medical innovations have been witnessed in this area in recent times. Levosimendan is a first-in-class calcium sensitizer and potassium channel opener indicated for the management of acute HF. Experience in several clinical studies has indicated that administration of intravenous levosimendan in intermittent cycles may reduce hospitalization and mortality rates in patients with advanced HF; however, none of those trials were designed or powered to give conclusive insights into that possibility. This paper describes the rationale and protocol of LeoDOR (levosimendan infusions for patients with advanced chronic heart failure), a randomized, double-blind, placebo-controlled, international, multicentre trial that will explore the efficacy and safety of intermittent levosimendan therapy, in addition to optimized standard therapy, in patients following hospitalization for acute HF. Salient features of LeoDOR include the use of two treatment regimens, in order to evaluate the effects of different schedules and doses of levosimendan during a 12 week treatment phase, and the use of a global rank primary endpoint, in which all patients are ranked across three hierarchical groups ranging from time to death or urgent heart transplantation or implantation of a ventricular assist device to time to rehospitalization and, lastly, time-averaged proportional change in N-terminal pro-brain natriuretic peptide. Secondary endpoints include changes in HF symptoms and functional status at 14 weeks
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