On the consequences of the uncertainty principle on the superconducting fluctuations well inside the normal state

We first argue that the collective behaviour of the Cooper pairs created by thermal fluctuations well above the superconducting transition temperature, Tc, is dominated by the uncertainty principle which, in particular, leads to a well-defined temperature, T^C, above which the superconducting coherence vanishes. On the grounds of the BCS approach, the corresponding reduced-temperature, ln(T^C/Tc), is estimated to be around 0.55, i.e., above T^C \approx 1.7Tc coherent Cooper pairs cannot exist. The implications of these proposals on the superfluid density are then examined using the Gaussian-Ginzburg-Landau approximation. Then we present new measurements of the thermal fluctuation effects on the electrical conductivity and on the magnetization in different low- and high-Tc superconductors with different dopings which are in excellent agreement with these proposals and that demonstrate the universality of ln(T^C/Tc).Comment: LaTeX, 10 pages, 3 figures, as published in Europhysics Letter

Changes in plasma biochemistry and body mass during incubation in the Yellow-legged Gull

The >Incubatory Reserves Constancy> hypothesis asserts that incubation could be a departure from breeding stress that allows for the maintenance or recovery of body reserves after laying effort (females) or territory defense (males) in those species with bi-parental incubation such as gulls. The plasma composition and body mass of incubating Yellow-legged Gulls (Larus cachinnans) were analyzed and related to the number of days after egg-laying. Female gulls showed an increase in uric acid and cholesterol levels, whereas males showed only an increase in uric acid values throughout this period. Moreover, females increased while males maintained their body masses. These results could reflect a recovery process after the laying effort supporting the Incubatory Reserves Constancy hypothesis in females. Uric acid and urea levels are positively correlated to body condition in Yellow-legged Gulls, which could be the result of a change in diet composition. This disagrees with recent findings on body composition in incubating gulls and could be related to variations in food availability among populations or years, and could reflect flexibility in the investment devoted by each sex.Peer Reviewe

An integrative approach to the anatomy of Syllis gracilis Grube, 1840 (Annelida) using micro-computed X-ray tomography

[Abstract] Background. The overall anatomy of the genus Syllis (Annelida: Syllidae) has been largely studied; however, an integrative approach considering different anatomical techniques has never been considered. Here, we use micro-computed X-ray tomography (micro-CT) to examine the internal anatomy of Syllis gracilis Grube, 1840, along with other widely available techniques. Methods. We studied the anatomy of the marine annelid S. gracilis through an integrative approach, including micro-CT along with stereo and light compound microscopy (STM, LCM), scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and histological sectioning (HIS). In this manner, we evaluated the applicability of micro-CT for the examination of annelid anatomy by testing whether the images obtained make it possible to visualize the main body structures, in comparison with other current techniques, of the various elements of its internal anatomy. Results. Overall external and internal body elements are clearly shown by the integrative use of all techniques, thus overcoming the limitations of each when studied separately.Any given method shows disparate results, depending on the body part considered. For instance, micro-CT provided good images of the external anatomy, including relevant characters such as the shape, length and number of articles of dorsal parapodial cirri. However, it is especially useful for the examination of internal anatomy, thus allowing for 3D visualization of the natural spatial arrangement of the different organs. The features best visualized are those of higher tissue density (i.e., body musculature, anterior parts of the digestive tract), particularly in 3D images of unstained specimens, whereas less electrodense tissues (i.e., the peritoneal lining of septa and nervous system) are less clearly visualized. The use of iodine stain with micro-CT has shown advantages against non-staining for the adequate observation of delicate elements of low density, such as the segmental organs, the connective between the ganglia, the ventral nerve cord and segmental nerves. Discussion. Main external anatomical elements of S. gracilis are well shown with micro-CT, but images show lesser optical resolution and contrast when compared to micrographs provided by SEM and CLSM, especially for fine structural features of chaetae. Comparison of micro-CT and HIS images revealed the utility and reliability of the former to show the presence, shape and spatial disposition of most internal body organs; the resolution of micro-CT images at a cellular level is, however, much lower than that of HIS, which makes both techniques complementary.Ministerio de Economía Industria y Competitividad; CGL2014-53332-C5-3-

Definition of an Artificial Reef Unit through Hydrodynamic and Structural (CFD and FEM) Models—Application to the Ares-Betanzos Estuary

[Abstract] The application of hydrodynamics to the definition of artificial reefs is of great interest since the positioning of the artificial reef modules on the sea floor alters the water velocity field, causing an appropriate circulation of nutrients and promoting a habitat for settling desired species. Nevertheless, the designs must be subjected to a structural calculation that will condition the constructive process to be applied. The present research proposes a methodology to determine the geometry of an artificial reef in terms of hydrodynamic and structural criteria. The solution proposed was analyzed through Computational Fluid Dynamics (CFD) and the Finite Element Method (FEM). Using concrete as base material for artificial reefs, four different dosages were proposed with different proportions of cement and water, leading to different mechanical properties, which determine different constructive strategies, such as dwell time in the mold. From the hydrodynamic point of view, it was found that the solution proposed provides a proper replacement of nutrients. From the structural point of view, it was found that the solution proposed does not need steel reinforcements in concrete, which improves the sustainability of the artificial reef. The four different concrete dosages will condition the constructive strategy through the dwelling time in the mold and, for any established production, the necessary number of molds (formworks).Xunta de Galicia; CN-10MMA003C

Anacardato de cálcio como promotor de crescimento para leitões na fase de creche

The objective of this work was to evaluate the effects of the dietary inclusion of calcium anacardate on the performance, diarrhea incidence, blood parameters, intestinal morphometry, and pH of gastrointestinal contents in piglets from 21 to 42 days of age. Sixty weaned Topigs piglets, with initial weight of 6.049±0.311 kg, were distributed in the following treatments: diet with or without antibiotic growth promoter (zinc bacitracin) and diets supplemented with increasing levels of calcium anacardate (0.4, 0.8, and 1.2%), with six replicates and two animals per experimental unit. No differences in performance (21 to 42 days of age), blood parameters, and villus height:crypt depth ratio were found between piglets fed diets containing calcium anacardate or antibiotic growth promoter. The replacement of the antibiotic growth promoter zinc bacitracin by calcium anacardate results in similar performance in piglets from 21 to 42 days of age, without changes in blood parameters and in the villus height:crypt depth ratio. The dietary inclusion of calcium anacardate does not decrease diarrhea incidence compared with the antibiotic zinc bacitracin.O objetivo deste trabalho foi avaliar os efeitos da inclusão do anacardato de cálcio em rações para leitões, dos 21 aos 42 dias de idade, sobre desempenho, ocorrência de diarreia, parâmetros sanguíneos, morfometria intestinal e pH dos conteúdos gastrintestinais. Foram avaliados 60 leitões desmamados da linhagem comercial Topigs, com peso inicial de 6,049±0,311 kg, distribuídos entre os seguintes tratamentos: rações com ou sem antibiótico promotor de crescimento (bacitracina de zinco) e rações contendo doses crescentes de anacardato de cálcio (0,4, 0,8 e 1,2%), com seis repetições e dois animais por unidade experimental. Não foram observadas diferenças no desempenho (21 a 42 dias de idade), nos parâmetros sanguíneos e na relação altura de vilosidade/profundidade de cripta entre leitões que receberam ração contendo anacardato de cálcio ou antibiótico promotor de crescimento. A substituição de antibiótico promotor de crescimento bacitracina de zinco pelo anacardato de cálcio resulta em desempenho semelhante de leitões dos 21 aos 42 dias de idade, e não altera os parâmetros sanguíneos e a relação altura de vilosidade/profundidade de cripta. A inclusão de anacardato de cálcio na ração não diminui a ocorrência de diarreia em comparação ao antibiótico bacitracina de zinco

A Perspective of Integrality. Ten years since the creation of UNLP Social Council

Desde la recuperación democrática las Universidades Nacionales Públicas han reconocido la importancia de la Extensión como la principal expresión del Compromiso Social Universitario. En la UNLP la reforma estatutaria del 2008 implicó un importante reconocimiento a la misma al precisarse sus alcances y significado. En base a ello y en un contexto de avance y consolidación de las organizaciones sociales en la vida social y política del país, la UNLP impulsó acciones que posibilitaron una mayor inserción en los territorios y una apertura a los diferentes actores sociales mediante la conformación del Consejo Social. A través de la construcción consensuada de una agenda comunitaria y de un permanente trabajo interactoral, el Consejo Social se propone abordar las principales problemáticas socio económicas, políticas, culturales y ambientales de la Región y acordar colectivamente estrategias de abordaje de las mismas. Desde su creación el Consejo Social ha llevado a cabo una experiencia que espera contribuir a la reorientación de las prácticas de docencia, investigación, transferencia y extensión, contribuyendo a la formación integral de los futuros profesionales, aportando a la consolidación de ciudadanías cada vez más democráticas. El propósito de este artículo es presentar la perspectiva y reflexiones surgidas a partir de la experiencia del Consejo Social, desarrollada desde su creación en 2010.Dossier: Prácticas universitarias e integralidad: escenarios y problemas actuales en diálogo con la sociedad.Especialización en Docencia Universitari

Una Perspectiva de la Integralidad. A 10 años de la creación del Consejo Social de la Universidad Nacional de La Plata

Since democratic recovery, the National Public Universities have recognized the importance of Extension as the main expression of the Social Commitment of Public Universities. In the UNLP, the statutory reform of 2008 implied an important recognition of this activity by specifying its scope and meaning. Based on this and in a context of progress and consolidation of social organizations in the social and political life of the country, the UNLP promoted actions that made possible a greater insertion in the territory, as well as an opening to different social actors, by means of the creation and consolidation of the Social Council. Through the consensual construction of a communitarian agenda and a permanent interactoral work, the Social Council intends to address the main socio-economic, political, cultural and environmental problems of the Region, collectively agreeing on strategies to address them. Since its creation, the Social Council has carried out a unique experience, which intends to contribute to the reorientation of teaching, research, transfer and extension practices, bettering a comprehensive training of future professionals, ultimately consolidating increasingly democratic citizenships. The purpose of this article is to present the perspective and reflections arising from the experience of the Social Council, developed since its creation in 2010.Desde la recuperación democrática las Universidades Nacionales Públicas han reconocido la importancia de la Extensión como la principal expresión del Compromiso Social Universitario. En la UNLP la reforma estatutaria del 2008 implicó un importante reconocimiento a la misma al precisarse sus alcances y significado. En base a ello y en un contexto de avance y consolidación de las organizaciones sociales en la vida social y política del país, la UNLP impulsó acciones que posibilitaron una mayor inserción en los territorios y una apertura a los diferentes actores sociales mediante la conformación del Consejo Social. A través de la construcción consensuada de una agenda comunitaria y de un permanente trabajo interactoral, el Consejo Social se propone abordar las principales problemáticas socio económicas, políticas, culturales y ambientales de la Región y acordar colectivamente estrategias de abordaje de las mismas. Desde su creación el Consejo Social ha llevado a cabo una experiencia que espera contribuir a la reorientación de las prácticas de docencia, investigación, transferencia y extensión, contribuyendo a la formación integral de los futuros profesionales, aportando a la consolidación de ciudadanías cada vez más democráticas. El propósito de este artículo es presentar la perspectiva y reflexiones surgidas a partir de la experiencia del Consejo Social, desarrollada desde su creación en 2010