Aerogel-based metasurfaces for perfect acoustic energy absorption

International audienceThe unusual viscoelastic properties of silica aerogel plates are efficiently used to design subwavelength perfect sound absorbers. We theoretically, numerically and experimentally report a perfect absorbing metamaterial panel made of periodically arranged resonant building blocks consisting of a slit loaded by a clamped aerogel plate backed by a closed cavity. The impedance matching condition is analyzed using the Argand diagram of the reflection coefficient, i.e., the trajectory of the reflection coefficient as a function of frequency in the complex plane. The lack or excess of losses in the system can be identified via this Argand diagram in order to achieve the impedance matching condition. The universality of this tool can be further exploited to design more complex metasurfaces for perfect sound absorption, thus allowing the rapid design of efficient absorbing metamaterials

El Portugal Salazarista frente a la democracia. El asesinato de Humberto Delgado y sus implicaciones internacionales

Con motivo de los cincuenta años del asesinato del general Humberto Delgado y su compañera Arajaryr Campos, en mafzo de 2015 se celebró en Badajoz, un congreso de historia sobre uno de los miembros más destacados de la oposición a la dictadura portuguesa, víctima en tierras españolas de un crimen de estado urdido por la policía política de Salazar. Entre los participantes de estas intensas jornadas de reflexión y debate se contaron algunos de los mayoles expertos en la historia de ias dictaduras ibéricas, de las relaciones entre ellas, y de la propia figura de Humberto Delgado. La calidad de las presentaciones animó a los organizadores del congreso a hacerlas accesibles a un amplio público, resultando la publicación que el lector tiene ahora en sus manos.info:eu-repo/semantics/publishedVersio

IMU-based monitoring of discharged patients with COVID-19 for the assessment of in-home recovering

No abstract available.publishe

Influence of the Incorporation of Basic or Amphoteric Oxides on the Performance of Cu-Based Catalysts Supported on Sepiolite in Furfural Hydrogenation

Cu-based catalysts supported on sepiolite have been tested in vapor-phase hydrogenation of furfural. The incorporation of basic or amphoteric metal oxides (magnesium oxide, zinc oxide, or cerium oxide) improves the catalytic behavior, reaching a maximum furfural conversion above 80% after 5 h of reaction at 210 ºC. In all cases, the main product is furfuryl alcohol, obtaining 2-methylfuran in lower proportions. The incorporation of these metal oxide species ameliorates the dispersion of metallic Cu nanoparticles, increasing the number of available Cu(0)-sites, which enhances the catalytic performance. The presence of acid sites favors the hydrogenolysis of furfuryl alcohol towards 2-methylfuran, although it also causes an increase of carbon species on its surface, which is associated with the catalytic deactivation of the catalyst along the time-on-stream.This research was funded by the Ministry of Economy and Competitiveness (Spain), grant numbers (CTQ2015-64226-C3-3-R, IEDI-2016-00743), Junta de Andalucía (Spain) (P12-RNM-1565), and FEDER (European Union) funds

Educación financiera, asesoramiento, estudio de pre-inversión y cultura de ahorro: factores de colocación de microcréditos

The present investigation is interested in the determination of the factors associated with the placement of microcredits in the Jardín Azuayo cooperative, Yanuncay office. The study is quantitative, exploratory, descriptive, and correlational. Part of a finite population of 9,206 research subjects. The research subjects are all active members of the Cooperativa Jardín Azuayo Yanuncay office. 103 study subjects were studied using an instrument validated by expert judgment and with a Cronbach's alpha of 0.884. The research is non-probabilistic and intentional. It was found that financial education, financial advice, pre-investment study, and savings culture are strongly correlated with the placement of microcredits. It is concluded that the analysis of the partner must be deeper considering the environment that is found and use this research for continuous improvement in advice on credit issues.La investigación se desenvuelve en el sector financiero de la economía popular y solidaria. El propósito consiste en determinar los factores asociados a la colocación de microcréditos en el caso de estudio la cooperativa de ahorro y crédito Jardín Azuayo, oficina Yanuncay. El estudio es de tipo cuantitativo y de alcance exploratorio, descriptivo y correlacional. La población es finita de 9 mil 206 sujetos de estudio, los socios activos de la entidad financiera cooperativa. El marco muestral son los listados de socios. Con un 95% de nivel de confianza se estableció un tamaño de muestra de 383 encuestas. La validación del cuestionario se hizo por criterio de jueces y la confiabilidad se midió por coeficiente de Alpha de Cronbach de 0,884. Se encontró que la educación financiera, el asesoramiento financiero, el estudio de pre inversión y la cultura de ahorro están correlacionados con la colocación de los micro créditos

Agricultural Practices to Mitigate Soil Degradation and Increase Carbon Capture

The implementation of new practices and their results to prevent or mitigate soil degradation and increase carbon capture were presented in this paper. The study was made on "Los Barzaga" farm, in the province of Guantanamo, where poor drainage conditions, low soil fertility and erosion affect 90% of the area, causing greater degradation and reduction of production. Several soil preservation and improvement procedures were established, considering the limiting factors identified. The physical and chemical indexes were evaluated, and the carbon reserves were monitored. The practices implemented (live and dead barriers, rill and reservoir correction), contributed to a 62 t. ha-1 reduction of soil loss, with positive changes in apparent density, infiltration and compacting velocity, and nutrient contents. Additionally, soil carbon increased to 20.67%

Actions to Restore Degraded Soil in the Southern Coastline of Guantanamo

ABSTRACT In the southern coastline of the province of Guantanamo, Cuba, there are communities that have lost several hectares of soil and biodiversity due to land mismanagement. "Los Cerezos" community is located in the municipality of Imias, as part of the “Eliomar Noa” UBPC (Basic Unit for Cooperated Production), which uses 99.2% of their areas for livestock raising. The land is on hills covered with xerophytic bushes; signs of degradation are clearly observed. Restoration is one alternative to revert this situation. It constitutes an effective preservation technique implemented by man to achieve optimum recovery of degraded ecosystems close to their original states. The aim of this paper is to evaluate the results achieved after recovery of local soils, using restoration techniques. Research was done in a fragmented forest, on typical red-brown fersiallitic soil, where the limiting factors were determined (rills, slopes, effective depth, organic matter content, rocks, and erosion), as well as other negative factors that may have an effect on vegetation growth. Common Ligum-vitae (Guaiacum officinalis L.) was used for reforestation due to its adaptability to the ecosystem. The restoration works helped create the conditions for progressive recovery of the areas and mitigate soil degradation, with a decrease in losses of 1 036 t. ha-1 every year, thanks to barrier accumulation

A Spanish adaptation of the Quality in Psychiatric Care Inpatient (QPC-IP) instrument: Psychometric properties and factor structure

Background and aim: Western countries share an interest in evaluating and improving quality of care in the healthcare field. The aim was to develop and examine the psychometric properties and factor structure of the Spanish version of the Quality in Psychiatric Care-Inpatient (QPC-IP) instrument. Methods: A psychometric study was conducted, translating the QPC-IPS instrument into Spanish, revision of the instrument by a panel of experts, and assessing its psychometric properties. 150 psychiatric inpatients completed the QPC-IP. Test-retest reliability was assessed by re-administering the questionnaire to 75 of these patients. Results: After conducting pilot testing and a cognitive interview with 30 inpatients, it was determined that the QPC-IPS was adequate and could be self-administered. A Cronbach's alpha of 0.94 was obtained for the full instrument and values of 0.52-0.89 for the various dimensions of the questionnaire. Test re test reliability: The Intraclass Correlation Coefficient for the full questionnaire was 0.69, while for the individual dimensions values between 0.62 and 0.74 were obtained, indicating acceptable temporal stability. Convergent validity was analysed using 10-point numerical satisfaction scale, giving a positive correlation (0.49). Confirmatory factor analysis revealed six factors consistent with the original scale. The Spanish version yielded adequate results in terms of validity and reliability. Conclusion: Our findings provide evidence of the convergent validity, reliability, temporal stability and construct validity of the Spanish QPC-IP for measuring patient quality in psychiatric care in Spanish hospitals. Hospital administrators can use this tool to assess and identify areas for improvement to enhance quality in psychiatric car

Spanish adaptation of the quality in psychiatric care-outpatient (QPC-OP) instrument community mental health patients' version: psychometric properties and factor structure

Background: Health systems in the field of mental health are strongly committed to community models that allow patients to be attended in their own environment. This helps them to maintain their family and social ties while trying to avoid costly hospital admissions. The patients' perspective is a key component in the assessment of the quality of psychiatric care and can even determine their adherence to the devices where they are treated. However, there are few instruments with adequate psychometric properties for the evaluation of the quality of psychiatric care in community mental health. The Quality in Psychiatric Care - Outpatient (QPC-OP) instrument has adequate psychometric properties to assess the quality of psychiatric care from the patients' perspective. The aim of this study was to adapt and validate the Spanish version of the QPC-OP instrument. Methods: A translation and back‑translation of the instrument was carried out. To examine its psychometric properties, the instrument was administered to 200 patients attending various community mental health services. To assess test‑retest reliability, the instrument was readministered after 7‑14 days (n = 98). Results: The Confirmatory Factor Analysis revealed a structure of 8 factors identical to the original version, with an adequate model fit. The internal consistency coefficient (Cronbach's alpha) was 0.951. The intraclass correlation coeff icient was 0.764 (95% IC: 0.649 - 0.842), and higher than 0.70 in 5 of the 8 factors. Additionally, an EFA was performed and revealed that the instrument could behave in a unifactorial or four factor manner in the sample analyzed. Conclusions: Results show that the Spanish version of the QPC-OP instrument is valid and reliable for the assessment of quality of psychiatric care in the community setting