Influence of Mn on the magnetocaloric effect of nanoperm-type alloys

In this paper, the influence of the Mn content on the magnetocaloric response of ribbon-shaped amorphous samples of Fe80−xMnxB20 x=10, 15, 18, 20, and 24 , has been studied. For this purpose, the temperature and field dependence of the magnetic entropy change SM have been obtained from magnetization curves. The partial substitution of Fe by Mn leads to a monotonous change in the Curie temperature TC of the alloys from 438 K for x=10 to 162 K for x=24, in agreement with the coherent-potential approximation. These Curie temperatures could make them good candidates to be used for magnetic refrigeration at room temperature. For an applied field of 1.5 T, the maximum entropy change SM pk passes from 1 J K−1 kg−1 x=10 to 0.5 J K−1 kg−1 x=24 , and the refrigerant capacity varies between 117 J kg−1 x=10 and 68 J kg−1 x=24 . A linear relationship between SM pk and the average magnetic moment per transition metal atom Fe,Mn has been presented. © 2010 American Institute of Physics

Alterations of antitumor and metabolic responses in L5178Y-R lymphoma-bearing mice after only 30-minute daily chronic stress exposure

Aim: In stress research, reducing times of stress induction may contribute to improving the well-being of experimental animals, especially in cancer models, already under physiological distress. To support this idea, we evaluated the effects of a short-timed stress protocol on endocrine, metabolic and immune indicators in mice bearing the L5178Y-R lymphoma. Materials and Methods: A 30-minute daily stress protocol was applied for 28 days to healthy and lymphoma-bearing BALB/c mice; body weight, plasma levels of corticosterone, norepinephrine, Th1/Th2 cytokines, insulin, and leptin, were measured. Results: We found a 12% significant decrease in body weight in non-tumor bearing mice under stress (p < 0.007). The disruption of weight evolution was accompanied by a stress induced 85% decrease in plasmatic leptin (p < 0.01) and total reduction of insulin. Tumor burden alone was associated to an increase in more than two-fold of plasmatic levels of norepinephrine (p < 0.008). Neither stress nor tumor or their combination, resulted in an elevation of systemic IL-6. IFN-γ levels were 20 times higher in lymphoma-bearing animals when compared with non-tumor bearing mice (p < 0.01); however, under stress, this response was reduced by half, indicating a suppressing effect of chronic stress on the antitumor immune response. Conclusion: A short-timed stress induction is enough to cause significant alterations in the metabolism and immunity of healthy and tumor-bearing mice, supporting the use of short-timed protocols as an efficient way to induce chronic stress that also considers concerns regarding the well-being of experimental animals in biomedical research

Relaciones Universidad - Empresa en el Contexto Paraguayo - Oportunidad para el Sistema de Innovación

[EN] This document outlines the development of the missions of universities as an evolutionary element of these organizations. The third mission is described as a participative link in social, business, entrepreneurial, and technological dimensions. Paraguayan universities currently have a limited theoretical, methodological, and technical understanding of the activities related to the third university mission. This document critically analyzes the national regulatory framework as a potential limitation to the exploitation of the knowledge, technologies, and capacities installed within the university. Envisioning the possibilities of third university mission activities allows for the dynamic enhancement of University-Enterprise Relationships (UER). The links between University-Enterprise Relationships (UER) require a robust contractual mechanism. Strengthening these mechanisms to facilitate the execution of these relationships not only presents an opportunity for innovation in the university environment but also as an economically beneficial possibility for the academic institution. Currently, the Autonomous University of Asunción has an Office of Research Results Transfer (OTRI) called Innova Lab - UAA. This entity represents an excellent opportunity to strengthen and promote the development of connections between UER in the city of Asunción. The office has all the necessary technical elements for the successful implementation of such relationships, including contractual models and specific linkage programs. These synergies will enable us to develop the third university mission at an international level and position the university at the forefront. The OTRI: Innova Lab - UAA serves as an interface structure, accompanying the process of transferring knowledge and technology to society through legal mechanisms in force in the country or location to be exploited. This enables diversification of income for researchers, inventors, students, and the rest of the university community through the protection of research and development results that may contain the potential to generate added value. Improving intra-institutional relationships by directing internal activities that allow for the management of research projects, prototype development, and innovation activities. This expands the opportunities for research results with the possibility of protection, envisioning technological and/or knowledge transfer. UER broadens the probabilities of generating such feedback opportunities to the system itself.[ES] El presente documento describe el desarrollo de las misiones de las Universidades como un elemento evolutivo de estas organizaciones. Siendo la tercera misional como un elemento de vinculación participativa en dimensiones sociales, empresarial, emprendedora y tecnológica. Las universidades paraguayas actualmente presentan una limitada comprensión teórica - metodológica y técnica de las actividades de las RUE a través de la tercera misión universitaria. El presente documento analiza documentalmente desde el marco normativo nacional como una posible limitante a la explotación de los conocimientos, tecnologías y capacidades instaladas de la universidad. Visualizar las posibilidades de las actividades de la tercera misión universitaria permite dinamizar las Relaciones Universidad Empresa (RUE). Los vínculos entre las relaciones universidad-empresa (RUE) necesitan un mecanismo contractual sólido. Reforzar estos mecanismos para facilitar la ejecución de estas relaciones no solo se presenta como una oportunidad para la innovación en el ámbito universitario, sino también como una posibilidad económica beneficiosa para la institución académica. En la actualidad, la Universidad Autónoma de Asunción cuenta con una Oficina de Transferencia de Resultados de Investigación (OTRI) denominada Innova Lab - UAA. Esta entidad representa una excelente oportunidad para fortalecer y fomentar el desarrollo de las conexiones entre RUE en la ciudad de Asunción. La oficina cuenta con todos los elementos técnicos necesarios para la implementación exitosa de este tipo de relaciones, incluyendo modelos contractuales y programas específicos de vinculación. Estas sinergias nos permitirán desarrollar la tercera misional de las universidades vigente a nivel internacional y colocar a la universidad como una organización a la vanguardia. La OTRI: Innova Lab - UAA es una estructura de interfaz, son oficinas acompañan el proceso de transferencia de conocimientos y de tecnología a la sociedad a través de mecanismos legales vigentes en el país o en el lugar a explotar. Permitiendo diversificar ingresos para los investigadores, inventores, estudiantes y resto de la comunidad universitaria, a través de la protección de los resultados de investigación y desarrollo que puedan contener una posibilidad de generar valor agregado. Mejorar las relaciones intra-institucionales direccionando actividades internas que permitan direccionar gestión de proyectos de: investigación, desarrollo de prototipos y actividades de innovación. A ampliarse las oportunidades de resultados de investigación con posibilidad de protección, visualizando la trasferencia tecnológica y/o de conocimientos. Las REU amplían las probabilidades de generar este tipo de oportunidades de retroalimentación al mismo sistema.Flores-Alatorre, JF.; Caballero-García, CR.; Arroyo-Vázquez, M.; Pacheco-Blanco, B. (2023). Relaciones Universidad - Empresa en el Contexto Paraguayo - Oportunidad para el Sistema de Innovación. Revista Internacional de Investigación en Ciencias Sociales. 19(2):351-372. https://doi.org/10.18004/riics.2023.diciembre.35135137219

The Mass-Metallicity relation explored with CALIFA: I. Is there a dependence on the star formation rate?

We present the results on the study of the global and local M-Z relation based on the first data available from the CALIFA survey (150 galaxies). This survey provides integral field spectroscopy of the complete optical extent of each galaxy (up to 2-3 effective radii), with enough resolution to separate individual HII regions and/or aggregations. Nearly $\sim$3000 individual HII regions have been detected. The spectra cover the wavelength range between [OII]3727 and [SII]6731, with a sufficient signal-to-noise to derive the oxygen abundance and star-formation rate associated with each region. In addition, we have computed the integrated and spatially resolved stellar masses (and surface densities), based on SDSS photometric data. We explore the relations between the stellar mass, oxygen abundance and star-formation rate using this dataset. We derive a tight relation between the integrated stellar mass and the gas-phase abundance, with a dispersion smaller than the one already reported in the literature ($\sigma_{\Delta{\rm log(O/H)}}=$0.07 dex). Indeed, this dispersion is only slightly larger than the typical error derived for our oxygen abundances. However, we do not find any secondary relation with the star-formation rate, other than the one induced due to the primary relation of this quantity with the stellar mass. We confirm the result using the $\sim$3000 individual HII regions, for the corresponding local relations. Our results agree with the scenario in which gas recycling in galaxies, both locally and globally, is much faster than other typical timescales, like that of gas accretion by inflow and/or metal loss due to outflows. In essence, late-type/disk dominated galaxies seem to be in a quasi-steady situation, with a behavior similar to the one expected from an instantaneous recycling/closed-box model.Comment: 19 Pages, 8 figures, Accepted for Publishing in Astronomy and Astrophysics (A&A

Principales resultados del estudio de mercado a empresas de la Ciudad de Asunción en el área de desarrollo e innovación y oportunidad en servicios de trasferencia en una Universidad de la Cd. de Asunción

El presente documento forma parte de los productos generados del proyecto creación de la Oficina de Trasferencia Tecnológica en la Universidad Autónoma de Asunción (UAA) financiado por el Consejo Nacional de Ciencia y Tecnología del Paraguay. El objetivo general de este estudio fue recopilar y analizar la información correspondiente al contexto de innovación y desarrollo actual en el Paraguay, para el desarrollo de la OTRI (Innova-Lab-UAA), en el periodo del 2020 al 2021. La metodología fue de tipo descriptivo trasversal con componentes analíticos y un enfoque fue cuantitativo. Entre los principales resultados encontramos que en el levantamiento de datos a 38 (treinta y ocho) empresas, el perfil de las mismas muestra que el 94,7% fueron empresas privadas, de las cuales el 84% lo son sin participación extranjera en el capital de la empresa y el 86,8% realizan operaciones comerciales a nivel nacional. Las empresas analizadas presentan un nivel de facturación de menos de 1000 millones de guaraníes en un 64%. En cuanto a sus necesidades sentidas del mercado en su componente de Innovación Empresarial encontramos que el 76,32% no ha participado en apoyos o incentivos del gobierno para la innovación; al 81,0% le interesaría participar en programas de fortalecimiento, mientras que solamente el 13,16% tiene un área de innovación y solo un 10,53% cuenta con fondos para la innovación. Hemos podido comprobar a través del estudio que existen las condiciones en el entorno productivo (empresas) para que se generen vínculos con el medio (universidad – empresa), a través de la instalación de una estructura de interfaz como las Oficinas de Trasferencia Tecnológica y de Resultados de Investigación (OTRI)

Where do seedlings go? A spatio-temporal analysis of seedling mortality in a semi-arid gypsophyte

Studies of seedling population dynamics often focus on survival because it provides an integrated measure of seedling performance. However, this approach involves a substantial loss of information because survival is the net result of a wide range of mechanisms. The present study overcomes these shortcomings by investigating spatial and temporal patterns in the causes of plant mortality in a population of Helianthemum squamatum seedlings. We use new point pattern analyses based on K functions combined with a new null model (‘‘independent labeling’’). A total of 871 seedlings of H. squamatum were mapped and regularly monitored over an 18-month period. More than 60% of seedlings died during this period. Causes of mortality were spatially structured, and these structures shifted through time. Small differences in either the time of emergence or the environment surrounding H. squamatum seedlings had profound influences on their fate. Seedlings emerging late in the season under the canopy of adult plants died from drought more often than expected, whereas those emerging earlier in the same microsite survived more than expected. The identity of neighbors also affected the spatio-temporal dynamics of mortality causes. Our results show that seedling-adult interactions cannot be easily predicted from simple models, and that the time of seedling emergence, its age and the identity of its neighbors determine the sign and the spatial scale of these interactions. The new methods introduced in this article open an avenue for the detailed analyses of the spatio-temporal dynamics of plant mortality and can help to disentangle the complexity of biotic interactions along environmental severity gradients

Salud bucodental y utilización de servicios odontológicos

En el Paraguay, los datos epidemiológicos sobre la salud bucodental y la utilización de los servicios en adultos son limitados, de ahí, la urgente necesidad de generar información para diseñar y establecer programas de salud pública acordes a las necesidades de dicha población. El objetivo de este estudio transversal retrospectivo fue determinar la situación de salud bucodental y el patrón de utilización de los servicios odontológicos de los pacientes atendidos en las cátedras de Operatoria Dental II y III de la carrera de Odontología de la Universidad Católica-Campus de Itapúa. La muestra incluyó 411 historias clínicas odontológicas de pacientes atendidos entre 2014 y 2017. La edad promedio de los pacientes fue de 28 años. La prevalencia de caries fue del 94,6%. El Índice de dientes cariados, perdidos y obturados promedio fue de 13,2 (DE± 6,9), siendo el mayor componente el de dientes cariados (7,0±4,5), seguido por el de dientes perdidos (4,4±5,7). Un alto porcentaje (77%) de los pacientes no tenía seguro médico al momento de consultar. El motivo de consulta actual del 42% fue la estética y el 64% sólo consulta al dentista cuando necesita. El valor promedio del índice de dientes cariados, perdidos y obturados (13,2) es catalogado como grave. El predominio de los componentes dientes cariados y perdidos es indicativo de un limitado acceso a los servicios odontológicos y tratamientos restauradores. Se requiere la instauración de estrategias de promoción de la salud y prevención de las afecciones bucodentales enmarcadas dentro de programas desde el primer nivel de atención

Consanguineous marriages and endemic malaria: can inbreeding increase population fitness?

<p>Abstract</p> <p>Background</p> <p>The practice of consanguineous marriages is widespread in countries with endemic malaria. In these regions, consanguinity increases the prevalence of α⁺-thalassemia, which is protective against malaria. However, it also causes an excessive mortality amongst the offspring due to an increase in homozygosis of recessive lethal alleles. The aim of this study was to explore the overall effects of inbreeding on the fitness of a population infested with malaria.</p> <p>Methods</p> <p>In a stochastic computer model of population growth, the sizes of inbred and outbred populations were compared. The model has been previously validated producing results for inbred populations that have agreed with analytical predictions. Survival likelihoods for different α⁺-thalassemia genotypes were obtained from the odds of severe forms of disease from a field study. Survivals were further estimated for different values of mortality from malaria.</p> <p>Results</p> <p>Inbreeding increases the frequency of α⁺-thalassemia allele and the loss of life due to homozygosis of recessive lethal alleles; both are proportional to the coefficient of inbreeding and the frequency of alleles in population. Inbreeding-mediated decrease in mortality from malaria (produced via enhanced α⁺-thalassemia frequency) mitigates inbreeding-related increases in fatality (produced via increased homozygosity of recessive lethals). When the death rate due to malaria is high, the net effect of inbreeding is a reduction in the overall mortality of the population.</p> <p>Conclusion</p> <p>Consanguineous marriages may increase the overall fitness of populations with endemic malaria.</p

A new WHO bottle bioassay method to assess the susceptibility of mosquito vectors to public health insecticides: results from a WHO-coordinated multi-centre study

BACKGROUND: The continued spread of insecticide resistance in mosquito vectors of malaria and arboviral diseases may lead to operational failure of insecticide-based interventions if resistance is not monitored and managed efficiently. This study aimed to develop and validate a new WHO glass bottle bioassay method as an alternative to the WHO standard insecticide tube test to monitor mosquito susceptibility to new public health insecticides with particular modes of action, physical properties or both. METHODS: A multi-centre study involving 21 laboratories worldwide generated data on the susceptibility of seven mosquito species (Aedes aegypti, Aedes albopictus, Anopheles gambiae sensu stricto [An. gambiae s.s.], Anopheles funestus, Anopheles stephensi, Anopheles minimus and Anopheles albimanus) to seven public health insecticides in five classes, including pyrethroids (metofluthrin, prallethrin and transfluthrin), neonicotinoids (clothianidin), pyrroles (chlorfenapyr), juvenile hormone mimics (pyriproxyfen) and butenolides (flupyradifurone), in glass bottle assays. The data were analysed using a Bayesian binomial model to determine the concentration-response curves for each insecticide-species combination and to assess the within-bioassay variability in the susceptibility endpoints, namely the concentration that kills 50% and 99% of the test population (LC50 and LC99, respectively) and the concentration that inhibits oviposition of the test population by 50% and 99% (OI50 and OI99), to measure mortality and the sterilizing effect, respectively. RESULTS: Overall, about 200,000 mosquitoes were tested with the new bottle bioassay, and LC50/LC99 or OI50/OI99 values were determined for all insecticides. Variation was seen between laboratories in estimates for some mosquito species-insecticide combinations, while other test results were consistent. The variation was generally greater with transfluthrin and flupyradifurone than with the other compounds tested, especially against Anopheles species. Overall, the mean within-bioassay variability in mortality and oviposition inhibition were < 10% for most mosquito species-insecticide combinations. CONCLUSION: Our findings, based on the largest susceptibility dataset ever produced on mosquitoes, showed that the new WHO bottle bioassay is adequate for evaluating mosquito susceptibility to new and promising public health insecticides currently deployed for vector control. The datasets presented in this study have been used recently by the WHO to establish 17 new insecticide discriminating concentrations (DCs) for either Aedes spp. or Anopheles spp. The bottle bioassay and DCs can now be widely used to monitor baseline insecticide susceptibility of wild populations of vectors of malaria and Aedes-borne diseases worldwide