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By the end of last century the distribution range of Microtus arvalis in NW Spain greatly expanded and outbreaks began to be reported in recently-colonised agricultural habitats. Ever since, novel impacts to regional farming, biodiversity conservation and public health have recurrently been associated to vole outbreaks. Here we present the first attempt to reconstruct recent changes of common vole dynamics and distribution in the NW of the Iberian Peninsula. We compile published information for the last 50 years and describe a new methodological approach based on semi-quantitative data obtained from complementary sources. Our results show how, from late-1970s, the entire lowland plains of Castilla y León region were rapidly (< 20 years) filled in by expanding populations. Analyses of outbreaks also suggest a 5-year cyclic pattern from late-1970s onwards, contrasting with the typical 3-year cycle described in most populations of this species. Our results contribute to improve the current knowledge of rodent dynamics in Europe and may serve as a baseline to local pest management programmes.

Ecologically-based pest management using biological control has been successfully tested elsewhere, but it has never been evaluated for cyclic vole plagues in Europe. We report the first large-scale replicated experiment to study the usefulness of artificially increasing populations of Common kestrels (Falco tinnunculus) and Barn owls (Tyto alba) to control common vole populations in agricultural habitats where nesting sites for raptors are scarce. The first preliminary results suggest: 1) population density of both predator species may be increasing in response to both nest-site availability and rodent density; 2) voles are a major prey; and 3) vole density during an increase phase of the population cycle may be reduced near nest-boxes.

As the optical power transmitted by an optical fibre under tensile stress varies with strain, it can be used as a sensor for strain monitoring in structural elements. In the present work, quasi-static tensile tests of step index polymer optical fibres (POF) with simultaneous measurement of surface temperature and optical power are described. Young's modulus, yield stress and tensile strength are derived from experimental tests. Morphological characterization of the POF fibres using scanning electron microscope images and differential calorimetry technique is performed. The contributions of both elastic and plastic strain components to the variation of temperature and optical power loss are also estimated. The evolution of the POF mechanical properties as well as that of temperature and optical power loss is explained in terms of the progressive relative movement and alignment of the molecular chains in the direction of the applied load. Strain, temperature and optical power loss are then correlated. [ABSTRACT FROM AUTHOR]

Background: Increased serum immunoglobulin (Ig) E values are frequently found in alcoholics. Cytokines produced by T-helper-2 (Th2) lymphocytes are required for IgE synthesis. Chronic alcoholism is associated with altered cytokine balance. This study analyzed the relationship between Th1 and Th2 cytokine production by stimulated peripheral blood mononuclear cells (PBMCs) and serum IgE levels, both in atopic and nonatopic alcoholics. Methods: Twenty-five patients admitted to the hospital with alcohol withdrawal syndrome were included in the study. Five were classified as atopic and 20 as nonatopic by means of skin-prick tests. Interleukin-4 (IL-4), IL-10, IL-12, IL-13, and interferon γ were measured in the supernatants of 48-hr cultures of PBMCs stimulated with phytohemagglutinin. Total serum IgE was measured by chemiluminescent enzyme immunoassay. Results were compared with those of 15 healthy controls (seven atopics and eight nonatopics). Results: Total serum IgE concentrations were higher in alcoholics than in controls, in both atopic and nonatopic subjects. The ratio of IL-4 to interferon γ production by phytohemagglutinin-stimulated PBMCs (as an approach to Th2/Th1 balance) was significantly lower in alcoholics than in healthy controls, both in the atopic and in the nonatopic group. No difference was observed regarding IL-10, IL-12, and IL-13 production between alcoholics and controls. No correlation was demonstrated between cytokine production and total serum IgE levels in any group. Conclusions: Increased total serum IgE is observed in alcoholics together with a paradoxically low ratio of Th2 to Th1 cytokine production by phytohemagglutinin-stimulated PBMCs. These findings are independent of the atopic status of patients. [ABSTRACT FROM AUTHOR]

Abstract Rabbits are the staple prey for Black Kites in Matasgordas, south-western Spain. Because of their poor predatory skills, it has been considered that most of the Rabbits consumed by Kites were young and affected by myxomatosis. After rabbit haemorrhagic disease (RHD) arrived in Spain, and since most of the Rabbits affected were adults, it was expected that the raptor would benefit with the incorporation of larger Rabbits in its diet. In concordance with that prediction, during the immediate three years before the arrival of RHD (1987–89), average size of Rabbits consumed by nestling Black Kites were similar and corresponded to the size of those Rabbits affected by myxomatosis. However, after RHD arrival in 1990, sizes of Rabbits consumed by Kites increased, corresponding to the age more frequently affected by RHD. [ABSTRACT FROM AUTHOR]