4,022 research outputs found

    Uso de hábitat de aves migratorias en el bosque sucesional de Cocha Cashu (Río Manu, Perú)

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    En el presente estudio se evaluaron las aves migratorias boreales y australes presentes desde el 15 de octubre al 15 de noviembre del 2014, para lo cual se emplearon ocho transectos diferenciados en cinco etapas del bosque sucesional en los márgenes izquierdo y derecho del río Manu correspondientes a  la Estación Biológica Cocha Cashu donde se registraron las especies de aves residentes y migratorias presentes realizando observaciones focales durante cinco minutos por cada especie migratoria encontrada, registrando la etapa de sucesión y el comportamiento mostrado; así mismo, se clasificaron las actividades de comportamiento en seis tipos: alimentación, locomoción, descanso, acicalado, vigilancia y agresión, obteniendo un registro total de 15 especies de aves migratorias,  las que representan al 16.3% del registro total de especies entre residentes y migratorias; entre el 24 al 26 de octubre incrementó el número de individuos por especie migratoria siendo Tyrannus tyrannus la especie con mayor número de individuos registrados. La etapa uno y la etapa tres son las que registran mayor presencia de aves migratorias; las actividades observadas con mayor porcentaje respecto al total de aves migratorias registradas fueron “vigilancia” con 34.16%, “locomoción” con 33.17% y “alimentación” con 25.74%. Varios estudios han demostrado que las aves migratorias exhiben una variación de espacio y tiempo  en el uso de hábitat y la selección entre hábitats alternativos al momento de realizar  escalas durante la migración.  Palabras clave: Cocha Cashu, bosque sucesional, aves migratorias,  río Manu, hábitat

    Influence of the molecular interaction in the value of molecular volume for the isotropicnematic transition of p-azoxianisol using th emodel HERSW in conjuntion with IPCM model

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    In this work, we analyzed the experimental pressure-temperature behavior in the Isotropic-Nematic phase transitionfor the liquid crystal p-azoxianisol at 1 atm using a development for the HERSW Conveg Peg model. Additionally, we obtained the values of the molecular volumes for the hard and attractive cores from theoretical quantum calculations at PM3, PM6 and B3LYP/6-311++G levels considering the molecular interaction among the liquidcrystals (PAA)5. We found that the best prediction for experimental data appears when the effect of the molecular interaction is considered in the volume calculation. Specifically for a/b=3.7, V0=70.86 A3 and a/bl=1.95 the best prediction was obtained

    Design Optimization of a Planar Spiral Inductor Using Space Mapping

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    This paper addresses the implementation of a computationally efficient optimization technique for designing structures simulated in 3D electromagnetic field solvers. A probe of concept is done by the EM-based optimization of a planar spiral inductor for high-power applications. The optimization technique employed is based on space mapping (SM) methods, more specifically on the Broyden-based input space mapping algorithm. Our optimization results confirm the efficiency of the proposed approach

    Appearance of room temperature ferromagnetism in Cu-doped TiO2δ_{2-\delta} films

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    In recent years there has been an intense search for room temperature ferromagnetism in doped dilute semiconductors, which have many potentially applications in spintronics and optoelectronics. We report here the unexpected observation of significant room temperature ferromagnetism in a semiconductor doped with nonmagnetic impurities, Cu-doped TiO2_2 thin films grown by Pulsed Laser Deposition. The magnetic moment, calculated from the magnetization curves, resulted surprisingly large, about 1.5 μB\mu_B per Cu atom. A large magnetic moment was also obtained from ab initio calculations using the supercell method for TiO2_2 with Cu impurities, but only if an oxygen vacancy in the nearest-neighbour shell of Cu was present. This result suggests that the role of oxygen vacancies is crucial for the appearance of ferromagnetism. The calculations also predict that Cu doping favours the formation of oxygen vacancies.Comment: 4 pages, 3 figures, published in Phys. Rev. B (Rapid Comm.

    Adaptación transcultural de un cuestionario para medir la calidad de vida de los pacientes con anticoagulación oral

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    ObjetivoAdaptar a la cultura y el idioma españoles un cuestionario desarrollado para evaluar la calidad de vida de los pacientes con tratamiento anticoagulante oral (TAO) y medir su validezDiseñoEstudio observacional, descriptivo, de validación de un instrumento de medida de calidad de vida relacionada con la salud. Emplazamiento. Atención primaria y atención especializadaParticipantesUn total de 225 pacientes que incluía a todos los pacientes de nuestro centro que utilizan TAO y una muestra consecutiva de pacientes con TAO del servicio de hematología del hospital de referenciaMediciones principalesTraducción directa,traducción inversa y prueba de validez. Análisis factorial y agrupación por dimensiones de los ítems, análisis de la consistencia interna y análisis de correlación ítem-total de la versión definitiva del cuestionario en españolResultadosLa edad media de los pacientes fue de 65 ± 13 años, el 51,1% era mujer y el 45,8% era controlado en atención primaria. En el estudio de validez se realizó un análisis factorial con la extracción de 5 factores que explican el 41,62% del valor total de la varianza y la obtención de una agrupación diferente de la original, con unvalor de alfa de Cronbach global de 0,82 y de 0,56–0,74 en las diferentes dimensiones y análisis de correlación ítem-total con valores estadísticamente significativos, excepto en la pregunta número 29ConclusionesTras realizar la adaptación a la cultura y el idioma españoles de un cuestionario desarrollado para evaluar la calidad de vida de los pacientes con TAO, se ha obtenido un instrumento útil y válido para nuestro entornoObjectiveTo adapt to Spanish culture and language a questionnaire developed to evaluate the quality of life of patients taking oral anticoagulation treatment (OAT) and to measure its validityDesignA descriptive observation study to validate an instrument to measure health-related quality of lifeSettingPrimary and specialist careParticipants225 patients, all the patients at our centre who were on OAT and a consecutive sample of patients on OAT from the referral hospital's haemotology serviceMain measurementsDirect translation, back- translation, and pilot study. Factor analysis and item-dimension grouping, internal consistency analysis and analysis of the item- total correlation of the definitive version of the questionnaire in SpanishResultsMean age was 65 (SD=13 years); 51% were women; 45.8% were monitored in PC. Validity study: factor analysis extracted 5 factors that explained 41.62% of total variance value and obtained a grouping different from the original; Cronbach's alpha was .82 overall and ran from .56 to .74 in the various dimensions; and item-total correlation analysis had statistically significant values,except for question 29ConclusionsAfter adaptation to Spanish culture and language of a questionnaire developed to evaluate the quality of life of patients taking OAT, it was found to be a useful instrument, valid for use in our milie

    Genomic landscape and immune-related gene expression profiling of epithelial ovarian cancer after neoadjuvant chemotherapy

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    Ovarian cancerCàncer d'ovariCáncer de ovarioPlatinum-based neoadjuvant chemotherapy followed by interval debulking surgery is an accepted treatment for patients with stage III or IV epithelial ovarian cancer who are not suitable for primary debulking surgery. The identification of suitable adjuvant treatments in these patients is an unmet need. Here, we explore potential genomic characteristics (mutational and immune-associated expression profiles) in a series of patients undergoing neoadjuvant chemotherapy. Tumor samples from biopsy and interval debulking surgery were analyzed for mutational landscape and immune profiling, together with detailed immunohistochemistry using different immune cell markers, and correlated with clinicopathological characteristics and potential response to neoadjuvant chemotherapy. No major differences in the mutational landscape were observed in paired biopsy and surgery samples. Genomic loss of heterozygosity was found to be higher in patients with total/near-total tumor response. The immune gene expression profile after neoadjuvant chemotherapy revealed activation of several immune regulation-related pathways in patients with no/minimal or partial response. In parallel, neoadjuvant therapy caused a significant increase of tumor-infiltrating lymphocyte population abundance, primarily due to an augmentation of the CD8+ T cell population. Remarkably, these changes occurred irrespective of potential homologous recombination defects, such as those associated with BRCA1/2 mutations. Our study strengthens the use of loss of heterozygosity as a biomarker of homologous repair deficiency. The changes of immune states during neoadjuvant chemotherapy reveal the dynamic nature of tumor-host immune interactions and suggest the potential use of immune checkpoint inhibitors or their combination with poly-ADP polymerase inhibitors in high stage and grade epithelial ovarian cancer patients undergoing neoadjuvant therapy.This study was funded by GlaxoSmithKline (GSK). I.L. position is funded by Fundación Científica Asociación Española Contra el Cáncer (AECC), Predoctoral AECC 2019 grant number PRDMA19024LODE. L. Morales position is funded by AECC, Postdoctoral AECC 2019 grant number POSTD19036MORA. This study was partially co-funded by European Regional Development Fund (FEDER) grants from Science and Innovation (SAF2015-66015-R and PID2019-110758RB-I00 to J.M.P.) and Instituto de Salud Carlos III (CIBERONC no. CB16/12/00228 to J.M.P.)

    Ecological Connectivity of Trypanosoma cruzi Reservoirs and Triatoma pallidipennis Hosts in an Anthropogenic Landscape with Endemic Chagas Disease

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    Traditional methods for Chagas disease prevention are targeted at domestic vector reduction, as well as control of transfusion and maternal-fetal transmission. Population connectivity of Trypanosoma cruzi-infected vectors and hosts, among sylvatic, ecotone and domestic habitats could jeopardize targeted efforts to reduce human exposure. This connectivity was evaluated in a Mexican community with reports of high vector infestation, human infection, and Chagas disease, surrounded by agricultural and natural areas. We surveyed bats, rodents, and triatomines in dry and rainy seasons in three adjacent habitats (domestic, ecotone, sylvatic), and measured T. cruzi prevalence, and host feeding sources of triatomines. Of 12 bat and 7 rodent species, no bat tested positive for T. cruzi, but all rodent species tested positive in at least one season or habitat. Highest T. cruzi infection prevalence was found in the rodents, Baiomys musculus and Neotoma mexicana. In general, parasite prevalence was not related to habitat or season, although the sylvatic habitat had higher infection prevalence than by chance, during the dry season. Wild and domestic mammals were identified as bloodmeals of T. pallidipennis, with 9% of individuals having mixed human (4.8% single human) and other mammal species in bloodmeals, especially in the dry season; these vectors tested >50% positive for T. cruzi. Overall, ecological connectivity is broad across this matrix, based on high rodent community similarity, vector and T. cruzi presence. Cost-effective T. cruzi, vector control strategies and Chagas disease transmission prevention will need to consider continuous potential for parasite movement over the entire landscape. This study provides clear evidence that these strategies will need to include reservoir/host species in at least ecotones, in addition to domestic habitats.This study was funded by the Secretaria de Salud and Consejo Nacional de Ciencia y Tecnología (CONACyt) project MOR-2004-CO2-012 to JMR, and by the Universidad Nacional Autónoma de México (PAPIIT project 225408 to VS-C, and the Sistema de Informática para la Biodiversidad y el Ambiente [SIBA], and Tecnologías para la Universidad de la Información y la Computación. AEGC was funded with a scholarship from CONACyT for a M. Sc. degree in vector-borne diseases at the Instituto Nacional de Salud Publica. CNIC is funded with a scholarship from CONACyT for studies at the graduate program in Biomedical Sciences of the Universidad Nacional Autonoma de Mexico
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