187 research outputs found

    Toeplitz operators, pseudo-homogeneous symbols and moment maps on the complex projective space

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    Following previous works for the unit ball, we define quasi-radial pseudo-homogeneous symbols on the projective space and obtain the corresponding commutativity results for Toeplitz operators. A geometric interpretation of these symbols in terms of moment maps is developed. This leads us to the introduction of a new family of symbols, extended pseudo-homogeneous, that provide larger commutative Banach algebras generated by Toeplitz operators. This family of symbols provides new commutative Banach algebras generated by Toeplitz operators on the unit ball

    (S)TEM structural and compositional nanoanalyses of chemically synthesized glutathione-shelled nanoparticles

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    This work is focused on the characterization by transmission and scanning–transmission electron microscopy-related techniques of core–shell nanoparticles synthesized via chemical methods. Diferent semiconducting, pure metallic or oxide materials have been utilized as the core (cadmium telluride, gold, magnetite, or magnetite covered with gold) of the nanoparticle, while they have been, in all cases, functionalized by a thin amorphous glutathione layer, with the goal of using the nanoparticles in biomedical applications such as biomarkers, and computerized tomography and image magnetic resonance contrast agents. The results show that it is possible to visualize the glutathione layer using spectroscopic and imaging techniques, associated with electron microscopy (such as energy-dispersive X-ray spectroscopy and high-resolution transmission electron microscopy images), that this layer is present at the surfaces of all observed nanoparticles, and that it is no thicker than a few nanometers. Electron microscopy also revealed that the nanoparticles core is crystalline and, in average, around 5-nm size.Spanish Ministry of Economy and Competitiveness MAT2015-67354-R (Program “Plan I+D+i”, subprogram “Retos”)Spanish Ministry of Education and Culture Grants ICARO-173873Spanish Ministry of Education and Culture Grants FPU16-0438

    Consequences of the Covid-19 pandemic on complex multimorbid elderly: Follow-up of a community-based cohort. SAMAC3 Study

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    ©2023. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Accepted version of a Published Work that appeared in final form in Journal of Nursing Scholarship. To access the final edited and published work see https://doi.org/10.1111/jnu.12860Background: The restrictions imposed during the management of the pandemic led to lack of care of other health problems. Purpose: To assess changes in the health status of complex multimorbidity elderly, functional and cognitive capacities, perception of the social surroundings, care pro vided by the nurses, including nursing diagnosis and interventions, use of health ser vices, adverse events, and use of devices and technical help during the first 6 months of the Covid-19 pandemic. Design: A 1-year longitudinal cohort study was conducted. Methods: Ninety-seven complex multimorbid elderly attended in primary care were evaluated every 3 months in a health area of the Spanish National Health System (SNHS). The research was called “SAMAC3 study”. Results: Significant negative changes were observed in the functional and cognitive ca pacity of the elderly, and in several nursing diagnoses. A decrease was observed in the frequency of visit to the nurses, hospital admittance, length of hospital stays, and falls. Conclusions: The functional and cognitive capacities of the cohort became worse. However, a significant decrease in the frequency of use of health services was ob served. The nurses detected significant changes in activity-exercise, cognitive perception, and roles-relationships, but their interventions were mostly centered on resolving clinical matters that required immediate attention. Clinical Relevance: The present study allowed us to observe that a situation of social and health stress has worsened the health indicators of multimorbid elderly, and the clinical care of community nurses was insufficient to providing care for the deteriora tion of the physical and cognitive domains

    Four-channel self-compensating single-slope ADC for space environments

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    A multichannel high-resolution single-slope analogue-to-digital converter (SS ADC) is presented that automatically compensates for process, voltage and temperature variations, as well as for radiation effects, in order to be used in extreme environmental conditions. The design combines an efficient implementation by using a feedback loop that ensures an inherently monotonic and very accurate ramp generation, with high levels of configurability in terms of resolution and conversion rate, as well as input voltage range. The SS ADC was designed in a standard 0.35 μm CMOS technology. Experimental measurements of the performance and stability against radiation and temperature are presented to verify the proposed approach

    A Front-End ASIC for a 3-D Magnetometer for Space Applications by Using Anisotropic Magnetoresistors

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    This paper presents an application-specific integrated circuit (ASIC) aimed for an alternative design of a digital 3-D magnetometer for space applications, with a significant reduction in mass and volume while maintaining a high sensitivity. The proposed system uses magnetic field sensors based on anisotropic magnetoresistances and a rad-hard mixed-signal ASIC designed in a standard 0.35 μm CMOS technology. The ASIC performs sensor-signal conditioning and analogue-to-digital conversion, and handles calibration tasks, system configuration, and communication with the outside. The proposed system provides high sensitivity to low magnetic fields, down to 3 nT, while offering a small and reliable solution under extreme environmental conditions in terms of radiation and temperature.Ministerio de Ciencia e Innovación AYA2011-29967-C05-05, AYA2009-14212-C05-04, AYA2008-06420-C04-0

    OWLs: A mixed-signal ASIC for optical wire-less links in space instruments

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    This paper describes the design of a mixed-signal ASIC for space application and the techniques employed for radiation hardening and temperature effects compensation. The work is part of a planned long-term effort and collaboration between "Instituto de Microelectrónica de Sevilla (IMSE)", "Universidad de Sevilla (US)", and "Instituto Nacional de Técnica Aeroespacial (INTA)" aimed to consolidate a group of experienced mixed-signal space-ASIC designers. The initiative is partially funded by the Spanish National Research Program. The ASIC performs the function of an optical digital transceiver for diffuse-light intra-satellite optical communications. It has been designed in a 0.35μm CMOS technology from austriamicrosystems (ams). The chip has been manufactured and verified from a functional perspective. Radiation characterization is planned for the third quarter of 2012. Power- and temperature-stress tests, as well as life-tests are also planned for this next quarter, and will be carried out by Alter Technology TÜV Nord S.A.U. Given the previous characterization of the technology [1] and the hardening techniques employed in the design and layout, radiation is not expected to be a problem. The specified environmental limits are a pedestal hard limit of 50KRads with the goal of maximizing TID tolerance, SEU and SET LET-thresholds above 70MeV/(mg/cm2), and latchup free behavior up to the same LET limit. Concerning temperature, the specified operation range is from -90 to +125ºC, while the non-operating temperature range is from -135 to +150ºC.Ministerio de Ciencia e Innovación (MICINN) MEIGA AYA2009-14212-C05-04, AYA2008-06420-C04-0

    Superficial Characteristics and Functionalization Effectiveness of Non-Toxic Glutathione-Capped Magnetic, Fluorescent, Metallic and Hybrid Nanoparticles for Biomedical Applications

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    An optimal design of nanoparticles suitable for biomedical applications requires proper functionalization, a key step in the synthesis of such nanoparticles, not only for subsequent crosslinking to biological targets and to avoid cytotoxicity, but also to endow these materials with colloidal stability. In this sense, a reliable characterization of the effectiveness of the functionalization process would, therefore, be crucial for subsequent bioconjugations. In this work, we have analyzed glutathione as a means to functionalize four of the most widely used nanoparticles in biomedicine, one of which is a hybrid gold-magnetic-iron-oxide nanoparticle synthetized by a simple and novel method that we propose in this article. We have analyzed the colloidal characteristics that the glutathione capping provides to the different nanoparticles and, using information on the Z-potential, we have deduced the chemical group used by glutathione to link to the nanoparticle core. We have used electron microscopy for further structural and chemical characterization of the nanoparticles. Finally, we have evaluated nanoparticle cytotoxicity, studying cell viability after incubation with different concentrations of nanoparticles, showing their suitability for biomedical applications

    Local Lung Immune Response to Mycobacterium bovis Challenge after BCG and M. bovis Heat-Inactivated Vaccination in European Badger (Meles meles)

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    [EN] Tuberculosis (TB) vaccination could be used as a key part of integrated strategies for the disease’s control if an effective and safe vaccine under field conditions is obtained. Recent studies in Spain have evaluated the protective efficacy of two oral vaccines against experimental challenge with live intra-bronchial Mycobacterium bovis in captive badgers: the live-attenuated M. bovis BCG vaccine (Danish strain) and a heat-inactivated M. bovis (HIMB) vaccine. With the objective of increasing the knowledge of the cellular development progress of infection and generating further tools to discriminate between mild and severe TB lesions between and within animals, the immunopathology of tuberculous lesions was studied to characterize the local immune response (cell type profile) within lung granulomas from control (non-vaccinated), BCG vaccinated and HIMB-vaccinated experimentally infected badgers with M. bovis. Four immunohistochemical protocols, for the specific detection of macrophages, T lymphocytes, B lymphocytes and plasma cells within TB granulomas in formalin fixed sections of the right middle lung lobe (lobe targeted for the M. bovis delivery), were performed. Immunolabelled sections were scanned and five randomly selected areas were analyzed with digital image analysis software. The results were expressed as the proportion of the positively immunolabelled area within the total area of the selected site. Data was analyzed using the statistical analysis software (SAS). In the three treatment groups, macrophages were the most abundant inflammatory cells within the granulomas, followed by B lymphocytes and plasma cells. T lymphocyes were absent in those granulomas. This would suggest a predominance of a non-specific innate response mediated by phagocytic cells over an adaptative humoral immune response. The proportion of macrophages and plasma cells was higher in BCG and HIMB-vaccinated badgers, respectively, suggesting the establishment of an adaptative humoral response in HIMB-vaccinated badgers. The lower bacterial load at the lung level, as well as the volume of lesions in lungs using magnetic resonance imaging in badgers with the HIMB vaccine in relation with local immune response presented, must be highlighted, since it would be an advantage in favor of its use under field conditions in terms of reducing TB transmission and environmental contaminationSIThis work has been funded by Ministerio de Ciencia, Innovación y Universidades (MCIU) and the Agencia Estatal de Investigación (AEI) reference project RTI2018-096010-B-C21 (FEDER co-funded) and, by PCTI 2018–2020 (GRUPIN: IDI2018-000237) and FEDER. Ms. Cristina Blanco Vázquez was granted with a predoctoral fellowship funded by INIA-CCAA (FPI-INIA) (2018 call). Ms. Ileana Z. Martínez was supported by a Fundación Carolina PhD scholarship (2017 call). We have received funds by RTI2018-096010-B-C21 (FEDER co-funded) to cover publication cost

    Detección de Rickettsia sp. en la garrapata café del perro Rhipicephalus sanguineus (Acari: Ixodidae) en Matamoros, Coahuila, México

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    Se colectaron al azar 217 garrapatas sobre 72 perros domésticosen el municipio de Matamoros, Coahuila, éstas fueron identificadascomo Rhipicephalus sanguineus Latreille. Con la intención de determinar la presencia de la bacteria (Rickettsia sp.) causante de la fiebre manchada de las Montañas Rocosas (FMMR), las garrapatas se agruparon en muestras (n = 100) para pruebas moleculares, las hembras repletas de sangre fueron diseccionadas para obtener el contenido estomacal y los órganos internos. Las ninfas y los machos se maceraron para exponer el contenido interno. Empleando la técnica de CTAB se obtuvo ADN de cada pool, el cual fue sometido a ensayos de PCR para amplificar el gen gltA para la detección de Rickettsias. Se reporta la presencia de Rickettsia sp. en una frecuencia del 4% (4). El presente trabajo constituye el primer registro del agente causal de la fiebre manchada Rickettsia sp. en órganos internos de la garrapata café del perro, R. sanguineus a través de técnicas moleculares en el municipio de Matamoros, Coahuila, región endémica de esta enfermedad.

    Casos de estudio en México y Latinoamérica

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    Ante la presencia de conflictos sociales y territoriales, las comunidades organizadas buscan estrategias de solución y confrontación. Es el estudio de dichos movimientos, lo que motiva a la publicación de éste libro: Respuestas comunitarias ante conflictos ambientales. Casos de estudio en México y Latinoamérica, reúne catorce textos que analizan las respuestas sociales y documentan la acción colectiva de comunidades que se han organizado para autogestionar soluciones ante conflictos territoriales, económicos y ambientales, en su propio entorno. Las aportaciones de investigadores y activistas, desde enfoques teóricos y metodológicos particulares, exponen casos de estudio sobre organizaciones formales e informales que se han conformado para afrontar los retos que representan proyectos productivos como fábricas cementeras, mineras, puertos, productores de energía, entre otros. Los enfoques analíticos tocan también temas nodales en el estudio de la acción colectiva como la ética, el despojo, los derechos humanos y las estrategias de comunicación y visibilización. Este material, que reúne estudios hechos en distintos lugares de México y Latinoamérica, es un compendio de métodos de investigación y un acercamiento al estudio de los movimientos sociales.UAEMEX, CONACyT, SE
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