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Introducción: El hipotiroidismo es un trastorno endocrino común que resulta de la deficiencia de la hormona tiroidea. La prevalencia de hipotiroidismo manifiesto aumenta con la edad, con más del 10% de las mujeres mayores de 60 años que tienen hipotiroidismo subclínico. El Objetivo principal de este estudio fue evaluar la comparativa de la dosis matutina versus vespertina de levotiroxina en el tratamiento del hipotiroidismo. Metodologia:152 pacientes con hipotiroidismo primario sin tratamiento previo se dividieron en grupos de dosificación matutino (Grupo 1) y vespertino (Grupo 2) y se evaluó el cambio en el perfil bioquímico, el funcionamiento físico y la calidad de vida durante el transcurso de 12 semanas de estudio. Resultados: Al final de las 12 semanas, 70 (90,90 %) sujetos del Grupo 1 y 72 (96 %) del Grupo 2 alcanzaron el eutiroidismo. En la evaluación, los síntomas y las puntuaciones clínicos totales mejoraron en ambos grupos al final de las 6 y 12 semanas. Se observó una mejora significativa en el perfil tiroideo en ambos grupos al final de las 6 y 12 semanas (Pvalor

El Queso de Prensa, también llamado Costeño es elaborado artesanalmente a partir de leche cruda de vaca en la región de la Costa Chica del estado de Guerrero. Con el fin de conocer las características de los quesos artesanales mexicanos, el objetivo de esta investigación fue analizar los cambios en el recuento de bacterias mesófilas aerobias (BMA), microorganismos coliformes totales (CT), bacterias ácido lácticas (BAL) y estafilococos coagulasa positivos (ECP), durante la maduración (5, 30, 60 y 90 días) de quesos de prensa, elaborados por cuatro diferentes queserías (A, B, C y D) de Cuajinicuilapa, Guerrero, México. Una porción (25 g) de cada muestra de queso se homogeneizó con diluyente de peptona (225 ml) y se prepararon diluciones desde 10 -1 a 10 -6 con las que se sembraron placas 3M TM PetrifilmTM. Después de incubar a diferentes condiciones, según el tipo de microorganismo, se hicieron recuentos de BMA, CT, BAL y ECP. Los resultados mostraron que conforme avanzó el tiempo de maduración del Queso de Prensa, la carga microbiana disminuyó: BMA de 4 a 2, CT de 6 a 3, BAL de 6 a 2 y ECP de 5 a 2 log10 UFC g-1. Los cambios en los recuentos de los grupos bacterianos estudiados, pueden ser atribuidos a las transiciones fisicoquímicas y microbiológicas propias de la maduración del queso y a las características de la microbiota presente en cada una de las queserías. Los resultados de esta investigación aportan elementos para la caracterización microbiana de los quesos artesanales mexicanos.

En el presente tratado de cirugía plástica ofrecemos algunos de los procedimientos más relevantes en cirugía plástica y reconstructuiva. Ofrecemos los métodos más modernos en esta importante especialidad que ofrece una mejor calidad de vida en los pacientes.

La presente edición ofrece una serie de temas sobre Neurología en la práctica médica. Se hace una presentación clásica de la patología o procedimiento tomando en cuenta el accionar del médico general o el interno residente en dicha especialidad. Cuando ha sido posible se incluye un estudio de caso y bibliografía más reciente con epidemiología del Ecuador o Latinoamérica.

Altres ajuts: acords transformatius de la UAB A major foundation of trait-based ecology is that traits have an impact on individual performance. However, trait-growth relationships have not been extensively assessed in trees, especially outside tropical ecosystems. In addition, measuring traits directly related to physiological processes remains difficult and the differences between inter- and intraspecific relationships are seldom explored. Here, we use individual-level data on a set of hydraulic, leaf and stem traits to assess their ability to predict basal area increment (BAI) and growth efficiency (BAI per unit of tree leaf area, GE) among and within species for six dominant tree species along a water availability gradient under Mediterranean climate (Catalonia, NE Spain). Measured traits include: leaf mass per area (LMA), leaf nitrogen concentration (N), leaf C isotopic composition (δC), the leaf water potential at turgor loss (P), stem wood density (WD) and branch-level estimates of the Huber value (Hv), sapwood- and leaf-specific hydraulic conductivity (K and K) and resistance to xylem embolism (P). Trait-growth associations were generally weak, particularly for BAI and within species. High values of both growth metrics were associated with 'conservative' leaf and hydraulic traits. In particular, BAI was negatively associated with K (and wood density), while GE increased with LMA, allocation to sapwood relative to leaves (Hv) and resistance to xylem embolism (P). Climate effects on BAI and GE were indirectly mediated by changes in traits, stand structure and tree basal area. Overall, these results suggest that maintaining functionality over extended periods of time may be more important than maximum gas exchange or hydraulic capacity to achieve high radial growth under Mediterranean climates. Our study reveals that widely used 'functional traits' may be poor predictors of tree growth variability along environmental gradients. Moreover, trait effects (when present) do not necessarily conform to simple hypotheses based on our understanding of organ-level processes. An improved understanding of trait coordination along common axes of variation together with a revaluation of the variables that better reflect whole-tree performance can greatly improve our understanding of trait-growth relationships. A free Plain Language Summary can be found within the Supporting Information of this article.

Summary Land surface models (LSMs) typically use empirical functions to represent vegetation responses to soil drought. These functions largely neglect recent advances in plant ecophysiology that link xylem hydraulic functioning with stomatal responses to climate.We developed an analytical stomatal optimization model based on xylem hydraulics (SOX) to predict plant responses to drought. Coupling SOX to the Joint UK Land Environment Simulator (JULES) LSM, we conducted a global evaluation of SOX against leaf‐ and ecosystem‐level observations.SOX simulates leaf stomatal conductance responses to climate for woody plants more accurately and parsimoniously than the existing JULES stomatal conductance model. An ecosystem‐level evaluation at 70 eddy flux sites shows that SOX decreases the sensitivity of gross primary productivity (GPP) to soil moisture, which improves the model agreement with observations and increases the predicted annual GPP by 30% in relation to JULES. SOX decreases JULES root‐mean‐square error in GPP by up to 45% in evergreen tropical forests, and can simulate realistic patterns of canopy water potential and soil water dynamics at the studied sites.SOX provides a parsimonious way to incorporate recent advances in plant hydraulics and optimality theory into LSMs, and an alternative to empirical stress factors., See also the Commentary on this article by Anderegg & Venturas, 226: 1535–1538.

The motivation for this research work is to make delivery of the updated diagnostic study of the use of digital technology in libraries in Paraguay, taking as shows those that are located in the centers concerning education or headers, in the country called institutions center. Aiming at the investigative work on improving the availability and access to the information material for the benefit of the education and research. For the data collection uses the technique of observation and non-structured interview with the staff of the library, and to national benchmarks in technology development. Thus, the article presents the encroachment of technology, giving assessments in the national ICT concepts, digital divide and information literacy. To the knowledge that the libraries are centers for information, recreation and culture, the use and application of digital technology is considered appropriate and necessary to support the librarian management, with use of the technology. The quality and excellence in the management of libraries is given in the services it provides to its environment, its community, hence the usufruct of the technology located in the unit of information or library as a reference in the country. Forward in order to be the protagonist in technological innovations with the growth of the knowledge of citizenship in the literacy, communication and use of the information provided by the same. Is achieved citizens gradual incursion of technology, with research work objectives in promoting the sharing of information through technology, developing databases and the creation of networks towards the improvement of the availability and access to information materials. Resulting from this process, the effect of cooperative and collaborative information units in gathering information either directly for the educational community.

Characterizing functional trait variation and covariation, and its drivers, is critical to understand the response of species to changing environmental conditions. Evolutionary and environmental factors determine how traits vary among and within species at multiple scales. However, disentangling their relative contribution is challenging and a comprehensive trait–environment framework addressing such questions is missing in lichens. We investigated the variation in nine traits related to photosynthetic performance, water use and nutrient acquisition applying phylogenetic comparative analyses in lichen epiphytic communities on beech across Europe. These poikilohydric organisms offer a valuable model owing to their inherent limitations to buffer contrasting environmental conditions. Photobiont type and growth form captured differences in certain physiological traits whose variation was largely determined by evolutionary processes (i.e. phylogenetic history), although the intraspecific component was non-negligible. Seasonal temperature fluctuations also had an impact on trait variation, while nitrogen content depended on photobiont type rather than nitrogen deposition. The inconsistency of trait covariation among and within species prevented establishing major resource use strategies in lichens. However, we did identify a general pattern related to the water-use strategy. Thus, to robustly unveil lichen responses under different climatic scenarios, it is necessary to incorporate both among and within-species trait variation and covariation.

International audience; Summary Trait variability in space and time allows plants to adjust to changing environmental conditions. However, we know little about how this variability is distributed and coordinated at different organizational levels. For six dominant tree species in northeastern Spain (three Fagaceae and three Pinaceae) we quantified the inter- and intraspecific variability of a set of traits along a water availability gradient. We measured leaf mass per area (LMA), leaf nitrogen (N) concentration, carbon isotope composition in leaves (δ13C), stem wood density, the Huber value (Hv, the ratio of cross-sectional sapwood area to leaf area), sapwood-specific and leaf-specific stem hydraulic conductivity, vulnerability to xylem embolism (P50) and the turgor loss point (Ptlp). Differences between families explained the largest amount of variability for most traits, although intraspecific variability was also relevant. Species occupying wetter sites showed higher N, P50 and Ptlp, and lower LMA, δ13C and Hv. However, when trait relationships with water availability were assessed within species they held only for Hv and Ptlp. Overall, our results indicate that intraspecific adjustments along the water availability gradient relied primarily on changes in resource allocation between sapwood and leaf area and in leaf water relations.

Different functional and structural strategies to cope with water shortage exist both within and across plant communities. The current trend towards increasing drought in many regions could drive some species to their physiological limits of drought tolerance, potentially leading to mortality episodes and vegetation shifts. In this paper, we study the drought responses of Quercus ilex and Pinus sylvestris in a montane Mediterranean forest where the former species is replacing the latter in association with recent episodes of drought-induced mortality. Our aim was to compare the physiological responses to variations in soil water content (SWC) and vapor pressure deficit (VPD) of the two species when living together in a mixed stand or separately in pure stands, where the canopies of both species are completely exposed to high radiation and VPD. P. sylvestris showed typical isohydric behavior, with greater losses of stomatal conductance with declining SWC and greater reductions of stored non-structural carbohydrates during drought, consistent with carbon starvation being an important factor in the mortality of this species. On the other hand, Q. ilex trees showed a more anisohydric behavior, experiencing more negative water potentials and higher levels of xylem embolism under extreme drought, presumably putting them at higher risk of hydraulic failure. In addition, our results show relatively small changes in the physiological responses of Q. ilex in mixed vs. pure stands, suggesting that the current replacement of P. sylvestris by Q. ilex will continue.

Background and aims The relationship between plant carbon economy and drought responses of co-occurring woody species can be assessed by comparing carbohydrate (C) dynamics following drought and rain periods, relating these dynamics to species' functional traits. We studied nine woody species coexisting in a continental Mediterranean shrubland that experienced severe drought effects followed by rain. Methods We measured total non-structural carbohydrates (NSC) and soluble sugars (SS) in roots and stems during drought and after an autumn rain pulse in plants exhibiting leaf loss and in undefoliated ones. We explored whether their dynamics were related to foliage recovery and functional traits (height [H], specific leaf area [SLA], wood density [WD]). Key results During drought, NSC concentrations were overall lower in stems and roots of plants experiencing leaf loss, while SS decreases were smaller. Roots had higher NSC concentrations than stems. After the rain, NSC concentrations continued to decrease, while SS increased. Green foliage recovered after rain, particularly in plants previously experiencing higher leaf loss, independently of NSC concentrations during drought. Species with lower WD tended to have more SS during drought and lower SS increases after rain. In low-WD species, plants with severe leaf loss had lower NSC relative to undefoliated ones. No significant relationship was found between H or SLA and C content or dynamics. Conclusions Our community-level study reveals that, while responses were species-specific, C stocks overall diminished in plants affected by prolonged drought and did not increase after a pulse of seasonal rain. Dynamics were faster for SS than NSC. We found limited depletion of SS, consistent with their role in basal metabolic, transport and signalling functions. In a scenario of increased drought under climate change, NSC stocks in woody plants are expected to decrease differentially in coexisting species, with potential implications for their adaptive abilities and community dynamics.

[EN] Non-structural carbohydrates (NSC) in plant tissue are frequently quantified to make inferences about plant responses to environmental conditions. Laboratories publishing estimates of NSC of woody plants use many different methods to evaluate NSC. We asked whether NSC estimates in the recent literature could be quantitatively compared among studies. We also asked whether any differences among laboratories were related to the extraction and quantification methods used to determine starch and sugar concentrations. These questions were addressed by sending sub-samples collected from five woody plant tissues, which varied in NSC content and chemical composition, to 29 laboratories. Each laboratory analyzed the samples with their laboratory-specific protocols, based on recent publications, to determine concentrations of soluble sugars, starch and their sum, total NSC. Laboratory estimates differed substantially for all samples. For example, estimates for Eucalyptus globulus leaves (EGL) varied from 23 to 116 (mean = 56) mg g(-1) for soluble sugars, 6-533 (mean = 94) mg g-1 for starch and 53-649 (mean = 153) mg g-1 for total NSC. Mixed model analysis of variance showed that much of the variability among laboratories was unrelated to the categories we used for extraction and quantification methods (method category R-2 = 0.05-0.12 for soluble sugars, 0.10-0.33 for starch and 0.01-0.09 for total NSC). For EGL, the difference between the highest and lowest least squares means for categories in the mixed model analysis was 33 mg g-1 for total NSC, compared with the range of laboratory estimates of 596 mg g-1. Laboratories were reasonably consistent in their ranks of estimates among tissues for starch (r = 0.41-0.91), but less so for total NSC (r = 0.45-0.84) and soluble sugars (r = 0.11-0.83). Our results show that NSC estimates for woody plant tissues cannot be compared among laboratories. The relative changes in NSC between treatments measured within a laboratory may be comparable within and between laboratories, especially for starch. To obtain comparable NSC estimates, we suggest that users can either adopt the reference method given in this publication, or report estimates for a portion of samples using the reference method, and report estimates for a standard reference material. Researchers interested in NSC estimates should work to identify and adopt standard methods., M.G.R. was funded by McMaster fellowship (1158.C). S.P. was funded by Juan de la Cierva contract (MCI project) and project ARBALMONT/786-2012 (OPAN, MAAMA, Spain). F.P. was funded by Fondecyt 11121175. U.N. and M.T. were funded by the Estonian Ministry of Education and Science, grant IUT-8-3. N.G.M. and L.T.D. were funded by DOE-BER. H.D.A. was funded by LANL-LDRD. J.M.-V. was funded by the Spanish Government (CGL 2010-16376). S.H. was funded by the Montana Institute on Ecosystems' Graduate Enhancement Award from NSF EPSCoR Track-1 NSF-IIA-1443108. Valuable comments from Dr Mauricio Mencuccini (University of Edinburgh), Dan Binkley (Colorado State University) and two anonymous reviewers were also greatly appreciated.

This article aims to analyze some of the reasons that scientific research should be done in public universities in Paraguay. The importance of research to the development of human resources and highlights not only preparing generating high but also because it stimulates curiosity, innovation and creativity. It thus builds the foundation for the development of the country. In this work the need for greater coordination between the science and technology agencies and universities on the platform of applied research and technology is emphasized. It thus seeks to answer one of the many national problems such as inter-agency cooperation as a route for the transfer of information generated for achieving a better country. As a result, it emphasizes the influence of research activities in today's culture, as well as the importance for the assessment of the universities themselves