380 research outputs found
Instantaneous Reactive Power Theory in the Geometric Algebra Framework
In this paper, a new approach for instantaneous reactive power analysis in the geometric
algebra (GA) environment is presented. The different formulations of the instantaneous reactive
power theory (IRPT) proposed, to date, have been developed in three-phase systems. There, an
instantaneous power variable, and two/three reactive power variables, all handled independently,
were introduced. Thanks to GA, it is possible to carry out a global treatment where an instantaneous
power multivector is defined. Thus, in the same multidimensional entity all the power variables
are included. From the instantaneous power multivector, the instantaneous power current and
the instantaneous reactive current are determined. It should be noted that in this mathematical
framework there is no limitation on the number of phases, and the extension of the IRPT to the
analysis of multi-phase systems appears in a natural manner. In this study, a systematic approach
with the most relevant definitions and theorems corresponding to the proposed methodology has
been established. Two practical cases of five-phase and three-phase systems have been included to
apply the new established formulation
Principal Component Analysis Applied to Digital Pulse Shape Analysis for Isotope Discrimination
Digital pulse shape analysis (DPSA) techniques are becoming increasingly important for
the study of nuclear reactions since the development of fast digitizers. These techniques allow us to
obtain the (A, Z) values of the reaction products impinging on the new generation solid-state detectors.
In this paper, we present a computationally efficient method to discriminate isotopes with similar
energy levels, with the aim of enabling the edge-computing paradigm in future field-programmable
gate-array-based acquisition systems. The discrimination of isotope pairs with analogous energy
levels has been a topic of interest in the literature, leading to various solutions based on statistical
features or convolutional neural networks. Leveraging a valuable dataset obtained from experiments
conducted by researchers in the FAZIA Collaboration at the CIME cyclotron in GANIL laboratories,
we aim to establish a comparative analysis regarding selectivity and computational efficiency, as this
dataset has been employed in several prior publications. Specifically, this work presents an approach
to discriminate between pairs of isotopes with similar energies, namely, 12,13C, 36,40Ar, and 80,84Kr,
using principal component analysis (PCA) for data preprocessing. Consequently, a linear and cubic
machine learning (ML) support vector machine (SVM) classification model was trained and tested,
achieving a high identification capability, especially in the cubic one. These results offer improved
computational efficiency compared to the previously reported methodologies.Grant TED2021-131075B-I00 funded byMCIN/AEI/10.13039/501100011033. Grant PID2021-127711NB-I00 funded by MCIN/AEI/10.13039/501100011033
Photoelectrical reading in ZnO/Si NCs/p-Si resistive switching devices
The increasing need for efficient memories with integrated functionalities in a single device has led the electronics community to investigate and develop different materials for resistive switching (RS) applications. Among these materials, the well-known Si nanocrystals (NCs) have demonstrated to exhibit RS properties, which add to the wealth of phenomena that have been studied on this model material platform. In this work, we present ZnO/Si NCs/p-Si resistive switching devices whose resistance state can be electrically read at 0 V under the application of low-power monochromatic illumination. The presented effect is studied in terms of the inner structural processes and electronic physics of the device. In particular, the creation of conductive filaments through the Si NC multilayers induces a low-resistance path for photogenerated carriers to get extracted from the device, whereas in the pristine state charge extraction is strongly quenched due to the insulating nature of the NC-embedding SiO2 matrix. In addition, spectral inspection of the generated photocurrent allowed unveiling the role of Si NCs in the reported effect. Overall, the hereby shown results pave the way to obtain memories whose RS state can be read under low-power conditions
Diversidad y origen geográfico del recurso vegetal en los huertos familiares de Quintana Roo, México
El huerto familiar (HF) es un sistema agrícola que funciona como fuente de recursos naturales y sitio para el manejo y conservación de especies vegetales nativas e introducidas. Un ejemplo de su importancia se presenta en el área maya de la península de Yucatán, México. La conquista española es un aspecto fundamental en el desarrollo y evolución del HF, evento que favoreció la introducción de especies vegetales, lo que contribuyó a enriquecer y diversificar la flora del HF de la región. Actualmente, esta introducción es un proceso favorecido por la globalización comercial, fenómeno que ha generado cambios en el HF debido al abandono de las actividades del campo y a la búsqueda de recursos económicos fuera de éste. En la península de Yucatán se observa con mayor claridad en el estado de Quintana Roo, en donde el desarrollo socioeconómico ha favorecido que muchos campesinos mayas emigren de sus comunidades para buscar trabajo en las zonas turísticas. Para conocer el estado actual del recurso vegetal, se estudió la diversidad y origen geográfico de las especies vegetales presentes en el HF de Quintana Roo. Se caracterizaron 120 HF en tres regiones del estado: norte, maya y sur. Se registraron 449 especies correspondientes a 93 familias y 329 géneros. La familia mejor representada fue la Fabaceae con el 9.35% y el género mejor representado fueCitruscon el 2.0%. La región con mayor diversidad fue el norte (H’= 5,684). Las especies introducidas fueron principalmente de origen americano (65,8%). Recientemente, la globalización ha favorecido la introducción de especies de origen asiático, como el nim (Azadirachta indica) y el rambután (Nephelium lappaceum). Esto muestra la importancia de este fenómeno en la riqueza y diversidad actual de los huertos familiares de Quintana Roo
Preoperative toxoplasma gondii serostatus does not affect long-term survival of cardiac transplant recipients: analysis of the Spanish Heart Transplantation Registry
[Abstract] Background. It's unclear whether pre-transplant T. gondii seropositivity is associated with impaired survival in heart transplant recipients.
Objectives. To test the above-mentioned hypothesis in the Spanish Heart Transplantation Registry.
Methods. Post-transplant outcomes of 4048 patients aged > 16 years who underwent first, single-organ heart transplantation in 17 Spanish institutions from 1984 to 2014 were studied. Long-term post-transplant survival and survival free of cardiac death or retransplantation of 2434 (60%) T. gondii seropositive recipients and 1614 (40%) T. gondii seronegative recipients were compared.
Results. T. gondii seropositive recipients were older, had higher body mass index, and presented higher prevalence of hypertension, hypercholesterolemia, COPD and Cytomegalovirus seropositivity than T. gondii seronegative recipients. In univariable analysis, pre-transplant T. gondii seropositivity was associated with increased post-transplant all-cause mortality (non-adjusted HR 1.15; 95% CI 1.04–1.26). However, this effect was no longer statistically significant after multivariable adjustment by recipient's age and sex (adjusted HR 1.01, 95% CI 0.92–1.11). Extended multivariable adjustment by other potential confounders showed similar results (adjusted HR 0.99, 95% CI 0.89–1.11). T. gondii seropositivity had no significant effect on the composite outcome cardiac death or retransplantation (non-adjusted HR 1.08, 95% CI 0.95–1.24, p = 0.235). The distribution of the causes of death was comparable in T. gondii seropositive and T. gondii seronegative recipients. No statistically significant impact of donor's T. gondii serostatus or donor-recipient T. gondii serostatus matching on post-transplant survival was observed.
Conclusions. Our analysis did not show a significant independent effect of preoperative T. gondii serostatus on long-term outcomes after heart transplantation
Uso de compuestos nutracéuticos en nuevas formulaciones de piensos acuícolas
Trabajo presentado en las X Jornadas de Acuicultura en el Litoral Suratlántico: Nuevos retos y perspectivas para la sostenibilidad de la acuicultura, celebrado entre el 22 y 23 de noviembre de 2023 en Huelva.[EN] Different strategies have been followed to improve the aquaculture of main European farmed fish, such as genetic selection, refinements in culture conditions or enhanced feed formulation and management. However,
more knowledge is required to exploit fish phenotypic plasticity to obtain those that better match aquaculture or market conditions. The overall objective of this mini-review is to identify the latest productive traits recently
performed, mainly in commercial carnivorous species, and underlying biological processes that would be susceptible to improve the competitivity of aquaculture sector through nutritional issues. Thus, this work is
framed within the concepts of Circular Economy and Blue Growth, where it is intended to point out the use of natural compounds extracted from seaweeds, microalgae and by-products of the industry for their inclusion in
aquafeeds, allowing a more efficient use of more sustainable vegetable protein sources, and also to evaluate if these nutraceutical compounds counteract detrimental effects observed by nutritional interventions or
environmentally challenged.[ES] La producción acuícola ha seguido diferentes estrategias para su optimización a lo largo de las últimas décadas, como el desarrollo de la selección genética, la mejora de las condiciones de cultivo, o el avance en la
formulación y gestión de los piensos. Sin embargo, se requiere más conocimiento para explotar la plasticidad fenotípica de los peces para obtener aquellos que se ajusten mejor a las condiciones de la acuicultura o del
mercado. El objetivo general de esta mini-revisión es identificar los últimos avances realizados recientemente, principalmente en especies carnívoras comerciales, y los procesos biológicos subyacentes que serían
susceptibles de mejorar la competitividad del sector acuícola a través de intervenciones nutricionales. Así, este trabajo se enmarca dentro de los conceptos de Economía Circular y Crecimiento Azul, donde se pretende señalar el uso de compuestos naturales extraídos de algas, microalgas y subproductos de la industria para su inclusión en alimentos acuícolas, permitiendo un uso más eficiente de fuentes de proteínas vegetales más sostenibles, y también evaluar si estos compuestos nutracéuticos son capaces de contrarrestar los efectos perjudiciales observados por las formulaciones inadecuadas o desafiados por factores ambientales estresantes.This work was supported by the Projects “FEDER-UCA18-107182”, “FisioBream-II Call for Young Researchers CEI⋅MAR 2019”, “ALGAE4FISH-CEI·MAR Empresa 2018”, “VALINVA-CEI·MAR Empresa 2019”, “SeriBlue-CEI·MAR Empresa 2020”, and co-financed by the spin-off LifeBioencapsulation S.L. (Almería) and Biotechnology Biopolym S.A. (Granada)
Near barrier scattering of 8He on 208Pb
The exotic nucleus 8He is investigated by means of the measurement of the
angular distributions of the elastic channel and the 6He and 4He fragment yields produced
in the collision with a 208Pb target at two energies around the Coulomb barrier, 16 and
22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of
extracting information about the structure of 8He and the relevant reaction mechanisms.
In this contribution, details of the experimental setup and preliminary data on elastic cross
sections are reported
Calidad de las elecciones a titular del Ejecutivo en el Centro y Centro-occidente de México
Este libro, que tiene por objetivo analizar la calidad de las elecciones celebradas entre 2006 y 2011 para ocupar la titularidad del Poder Ejecutivo de las 14 entidades federativas de la República Mexicana que conforman las regiones Centro y Centro-occidente de este país, ha sido elaborado por investigadores pertenecientes a la Red Nacional de Investigación sobre la Calidad de la Democracia en México (Renicadem), la cual cuenta con un equipo de investigación en cada una de las entidades federativas del país. A su vez, esta Red constituye una de las cuatro líneas temáticas que componen la red temática del Conacyt “Sociedad civil y calidad de la democracia”. Con todo, la presente obra puede considerarse, en dos sentidos, como el resultado parcial de estudios realizados por investigadores que conforman la mencionada Renicadem. Por un lado, trata sólo de una de las varias dimensiones que esta Red ha establecido como necesarias para analizar la calidad de la democracia: la calidad electoral (otras dimensiones, que se encuentran en proceso de investigación, son calidad de vida, rendición de cuentas y Estado de derecho). También es parcial porque no abarca la totalidad de la República Mexicana, sino únicamente a las 14 entidades indicadas.UAE
Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)
This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe
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