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The articulation of efficiency and justice through institutions. Theoretical dialogue between D. C. North and A. MacIntyre
No full textPublisher Copyright: © 2024 Pontificio Seminario Mayor San Rafael. All rights reserved.The theoretical and practical search to articulate efficiency and justice has history and present relevance. The objective of this paper is a theoretical dialogue between D. C. North and A. MacIntyre to articulate efficiency and justice across institutions. This articulation has –as its broader horizon– an interdisciplinary approach to the relationship between economic theory and ethics. From economic science, as an alternative to the concept of Paretian efficiency, North speaks of adaptive efficiency: institutions – understood as rules of human interaction – seek to be efficient in a process of adaptation over time. From ethics, MacIntyre contributes from an Aristotelian-Thomistic vision of distributive justice. MacIntyre recognizes that institutions are necessary for practices in communities but warns of the danger of institutional corruption. A place for this articulation is companies –organizations for North– where adaptive efficiency can occur if institutions –rules for human interaction– decentralize decision-making, specify contracts and property rights well. Companies, understood by MacIntyre as workplaces, are institutions that pursue common goods and that support the practices of these communities
Recuento de células somáticas en vacas lecheras como indicador de mastitis subclínica en etapa de ordeña
No full textLa glándula mamaria es un órgano vulnerable a la entrada de microorganismos patógenos, es por ello que frente a su ingreso produce una patología infecto contagiosa llamada mastitis, la cual es considerada altamente prevalente afectando la calidad y cantidad de la leche producida. Se considera una patología multifactorial ya que está asociada a la sanidad de la glándula mamaria, agentes infecciosos, rutina de manejo y genética. Es una reacción inflamatoria de la glándula mamaria, produciendo alteraciones organolépticas de la leche, un aumento del número de células somáticas por la presencia de microorganismos y cambios en la funcionalidad de la glándula mamaria. Se puede presentar de forma clínica y subclínica, definiendo así su tratamiento. El presente estudio aborda la mastitis subclínica, caracterizada por no producir inflamación observable de la glándula mamaria, cambios macroscópicos en la leche o signología clínica en el animal. Por lo anterior, se detecta únicamente con pruebas que permitan realizar el diagnóstico mediante el recuento de células somáticas. La detección temprana de mastitis es primordial para disminuir la progresión de la patología, pérdidas en cantidad, calidad de la leche y tratamientos costosos. Por lo anterior, la pregunta de investigación que se plantea es ¿el recuento de células somáticas servirá como un indicador de mastitis en un rebaño? Se tomaron muestras de leche a 136 vacas de Lácteos San Sebastián, en la Región del Ñuble, y se determinó el recuento de células somáticas mediante Control Lechero Oficial. Posteriormente se estratificó porcentualmente el número de vacas de acuerdo al recuento de células y el grado de mastitis subclínica y se analizó la relación entre la cantidad de células somáticas y el número de partos en los animales. Finalmente, se reportó una tasa de positividad a mastitis subclínica de un 31%. A su vez, se determinó la existencia de una correlación positiva leve aunque estadísticamente significativa entre el número de animales mastitis subclínica y la cantidad de partos (coeficiente de Spearman = 0,23, p-value = 0,007). Pese a que la tasa de positividad encontrada es menor a la reportada por otros autores, la mastitis genera importantes pérdidas en la industria láctea, por lo que su detección temprana de ésta nos permite tomar una serie de medidas en tratamiento y prevención de esta. Al mismo tiempo, se plantea el Control Lechero Oficial como una herramienta para la supervisión de la salud del rebaño en futuras investigaciones.The mammary gland is an organ vulnerable to the entry of pathogenic microorganisms, which is why it produces an infectious pathology called mastitis, which is considered highly prevalent and affects the quality and quantity of milk produced. It is considered a multifactorial pathology since it is associated to the health of the mammary gland, infectious agents, management routine and genetics. It is an inflammatory reaction of the mammary gland, producing organoleptic alterations in the milk, an increase in the number of somatic cells due to the presence of microorganisms and changes in the functionality of the mammary gland. It can present in clinical and subclinical forms, thus defining its treatment. The present study deals with subclinical mastitis, characterized by not producing observable inflammation of the mammary gland, macroscopic changes in the milk or clinical signs in the animal. Therefore, it is detected only with tests that allow diagnosis by somatic cell count. Early detection of mastitis is essential to reduce the progression of the pathology, losses in quantity and quality of milk and costly treatments, and therefore, the research question is: Will the somatic cell count serve as an indicator of mastitis in a herd? Milk samples were taken from 136 cows of Lácteos San Sebastián, in the Ñuble Region, and the somatic cell count was determined by Official Dairy Control. Subsequently, the number of cows was stratified according to the cell count and the degree of subclinical mastitis, and the relationship between the number of somatic cells and the number of calvings in the animals was analyzed. Finally, a subclinical mastitis positivity rate of 31% was reported. A slight but statistically significant positive correlation was found between the number of subclinical mastitis animals and the number of calvings (Spearman's coefficient = 0.23, p-value = 0.007). Although the positivity rate found is lower than that reported by other authors, mastitis generates important losses in the dairy industry, so its early detection allows us to take a series of measures in its treatment and prevention. At the same time, the Official Dairy Control is proposed as a tool for monitoring herd health in future research
Biological role of fructose in the male reproductive system : Potential implications for prostate cancer
No full textPublisher Copyright: © 2023 Wiley Periodicals LLC.Background: Over the last 20 years, fructose has gradually emerged as a potential metabolic substrate capable of promoting the growth and progression of various cancers, including prostate cancer (PCa). The biological and molecular mechanisms that underlie the effects of fructose on cancer are beginning to be elucidated. Methods: This review summarizes the biological function of fructose as a potential carbon source for PCa cells and its role in the functionality of the male reproductive tract under normal conditions. Results: The most recent biological advances related to fructose transport and metabolism as well as their implications in PCa growth and progression suggest that fructose represent a potential carbon source for PCa cells. Consequently, fructose derivatives may represent efficient radiotracers for obtaining PCa images via positron emission tomography and fructose transporters/fructose-metabolizing enzymes could be utilized as potential diagnostic and/or predictive biomarkers for PCa. Conclusion:: The existing data suggest that restriction of fructose from the diet could be a useful therapeutic strategy for patients with PCa
Inflation and late-time accelerated expansion driven by k -essence degenerate dynamics
No full textPublisher Copyright: © 2024 authors. Published by the American Physical Society.We consider a k-essence model in which a single scalar field can be responsible for both primordial inflation and the present observed acceleration of the cosmological background geometry, while also admitting a nonsingular de Sitter beginning of the Universe (it arises from de Sitter and ends in de Sitter). The early one is driven by a slow-roll potential, and the late one is driven by a dynamical dimensional reduction process which freezes the scalar field in a degenerate surface, turning it into a cosmological constant. This is done by proposing a realizable stable cosmic time crystal, although giving a different interpretation to the "moving ground state", in which there is no motion because the system loses degrees of freedom. Furthermore, the model is free of pathologies such as propagating superluminal perturbations, negative energies, and perturbation instabilities
Hybrid DMS-ZVS-PWM with In-depth Mathematical Model for Boosting Efficiency of Grid-Connected SEPIC Differential Mode Inverter
No full textPublisher Copyright: AuthorsSingle-stage differential mode inverters (DMI) have been extensively utilized in three-phase grid-connected systems due to several advantages, such as few semiconductor devices resulting from their simple and modular configuration. Nevertheless, the modulation and control strategy require further enhancement to enable more efficient power conversion across various operations. Therefore, this paper introduces a detailed analytical model of the SEPIC-DMI, leading to the development of a hybrid discontinuous modulation scheme pulse width modulation (DMS-PWM), which incorporates zero voltage switching (ZVS), denoted as Hybrid DMS-ZVS-PWM approach. In the proposed strategy, the duty cycle of SEPIC-DMI is zero for one-third of the grid frequency cycle, which leads to minimizing conduction and switching power losses. Moreover, the voltage stress on the components is significantly reduced due to DMS-PWM. For ZVS, a simplified active-clamp circuit is proposed and designated using a single switch and two small capacitors. The proposed active-clamp circuit is integrated into the SEPIC-DMI to verify SEPIC power switches’ ZVS and zero current switching (ZCS). The ZVS/ZCS improves the inverter efficiency by major minimization in power losses. The mathematical derivations and performance measurements (simulation and experiment) are provided to show the superiority of the proposed hybrid DMS-ZVS-PWM method. The peak efficiency of SEPIC-DMI is enhanced from 90% to 94%, and the voltage stress is curtailed in all components with 13%.Single-stage differential mode inverters (DMI) have been extensively utilized in three-phase grid-connected systems due to several advantages, such as few semiconductor devices resulting from their simple and modular configuration. Nevertheless, the modulation and control strategy require further enhancement to enable more efficient power conversion across various operations. Therefore, this paper introduces a detailed analytical model of the SEPIC-DMI, leading to the development of a hybrid discontinuous modulation scheme pulse width modulation (DMS-PWM), which incorporates zero voltage switching (ZVS), denoted as Hybrid DMS-ZVS-PWM approach. In the proposed strategy, the duty cycle of SEPIC-DMI is zero for one-third of the grid frequency cycle, which leads to minimizing conduction and switching power losses. Moreover, the voltage stress on the components is significantly reduced due to DMS-PWM. For ZVS, a simplified active-clamp circuit is proposed and designated using a single switch and two small capacitors. The proposed active-clamp circuit is integrated into the SEPIC-DMI to verify SEPIC power switches’ ZVS and zero current switching (ZCS). The ZVS/ZCS improves the inverter efficiency by major minimization in power losses. The mathematical derivations and performance measurements (simulation and experiment) are provided to show the superiority of the proposed hybrid DMS-ZVS-PWM method. The peak efficiency of SEPIC-DMI is enhanced from 90% to 94%, and the voltage stress is curtailed in all components with 13%
Optimización de la distribución de distritos y la asignación de escaños para mejorar Representatividad en la Cámara de Diputados de Chile
No full textPublisher Copyright: © 2024 by the authors.This paper presents a mathematical programming model to simultaneously create districts and allocate seats in Chile’s Chamber of Deputies, improving representativeness. In addition, it explicitly incorporates constraints that ensure the contiguity of the communes that form the districts while respecting natural and administrative boundaries. Implementing specific strategies and methods has resulted in significant enhancements in particular metrics used to assess the degree of representativeness. These improvements have effectively addressed certain shortcomings and resulted in more accurate and reliable representation measurements in the given context. This study proposes a novel mathematical programming model that simultaneously tackles district creation and seat allocation for Chile’s Chamber of Deputies. This integrated approach aims to achieve a more representative body. The results demonstrate a substantial decrease in malapportionment, from 11.07 in the 2015 reform to 6.55 under the proposed model. Furthermore, the sum of deviations has diminished, and the number of overrepresented districts has decreased from 17 to 13 out of 28 districts. Consequently, the malapportionment has been significantly reduced and falls within the permissible range of deviations, as outlined by the European Commission for Democracy through Law
Factors influencing teaching choice as predictors of Teacher Identity in prospective Special Education teachers
No full textPublisher Copyright: © 2024, AUFOP. All rights reserved.La identidad docente ha sido estudiada como un constructo amplio, mutable e influenciado por múltiples factores durante su desarrollo. Pocas investigaciones han abordado los factores que podrían explicar la identidad docente durante la formación del profesorado de Educación Especial. El objetivo es establecer la capacidad explicativa de los factores motivacionales y perceptuales para la elección de la carrera sobre la identidad docente. Se empleó un enfoque cuantitativo con un diseño transversal explicativo. Participaron 180 estudiantes de la carrera de Pedagogía en Educación Especial de 10 universidades chilenas. Se aplicó el Fit-Choice Scale y la Escala de Medida de la Identidad Docente. Los datos fueron analizados con una regresión lineal bayesiana. Los resultados muestran que los factores de percepción por sí solos podrían explicar el comportamiento de la identidad docente, mientras que el modelo conjunto entre los factores de motivación, los factores de percepción para la elección de la carrera y variables sociodemográficas como la edad y tener un familiar docente muestra una mayor capacidad explicativa respecto de la identidad docente. Se espera que los resultados de esta investigación constituyan una aproximación a la explicación de los factores que influyen en el desarrollo de la identidad docente en futuros profesores de Educación Especial
Diagnóstico de dermatitis alérgica por picadura de pulga en perro doméstico (canis lupus familiaris) : Revisión bibliográfica
Get PDFLa dermatitis por alergia a las pulgas (DAP) es una enfermedad cutánea frecuente en el perro doméstico (Canis lupus familiaris), que se caracteriza por manifestar una irritación dérmica debido a las sustancias alergénicas presentes en la saliva de la pulga, provocando como principal signo clínico el prurito. El diagnóstico de la DAP se basa principalmente en un completo examen clínico en busca de presencia de pulgas o heces de pulga, así como la demostración de hipersensibilidad a través de pruebas cutáneas intradérmicas. El estudio se centró en analizar los signos clínicos y diferentes opciones de diagnóstico utilizados en la literatura científica sobre DAP en perros. Se realizó una revisión sistemática de artículos publicado entre los años 2000 y 2023, utilizando bases de datos académicas como PubMed, Scielo y Google Scholar. Los artículos fueron evaluados mediante criterios de elegibilidad, publicados en idioma inglés y español con enfoques diagnósticos aplicables. Se identificaron 15 estudios relevantes que proporcionaron información detallada sobre la presentación clínica de la enfermedad y sus respectivos enfoques diagnósticos. Los hallazgos revelaron que el prurito es el signo clínico más predominante reportado en los perros con DAP, seguido de eritema, pápulas y alopecia. Los métodos diagnósticos más utilizados incluyeron las pruebas intradérmicas y examen clínico general para la detección de signos clínicos. Se propuso un algoritmo diagnóstico basado en estos resultados, con el objetivo de direccionar el manejo diagnóstico de la DAP.Flea allergy dermatitis (FAD) is a common skin disease in the domestic dog (Canis lupus familiaris), characterized by dermal irritation due to allergenic substances present in flea saliva, causing pruritus as the main clinical sign. The diagnosis of DAP is based on a thorough clinical examination for fleas or flea feces and the demonstration of hypersensitivity through intradermal skin tests. The study focused on analyzing the clinical signs and different diagnostic options used in the scientific literature on DAP in dogs. A systematic review of articles published between 2000 and 2023 was performed, using academic databases such as PubMed, Scielo and Google Scholar. The articles were evaluated using eligibility criteria, published in English and Spanish with applicable diagnostic approaches. Fifteen relevant studies were identified that provided detailed information on the clinical presentation of the disease and their respective diagnostic approaches. The findings revealed that pruritus is the most predominant clinical sign reported in dogs with DAP, followed by erythema, papules, and alopecia. The most common diagnostic methods included intradermal testing and general clinical examination for detectingclinical signs. A diagnostic algorithm based on these results was proposed, with the aim of supporting the diagnostic accuracy and guiding the management of DAP, promoting the welfare of affected dogs
Gold(Ⅰ) organometallics with alkynyl and N-heterocyclic carbene ligands and their medicinal and computational chemistry evaluation as prospective anticancer drugs
No full textPublisher Copyright: © 2024Gold(Ⅰ) organometallics of the type alkynylgold(Ⅰ)(NHC) (where NHC = N-heterocyclic carbene) 5a – 5f and 6a/b were prepared and evaluated as prospective anticancer agents by computational and medicinal chemistry methods. DFT calculations showed similar stability for the series, with differing dipole moments, depending on the substituents on the alkynyl and the NHC ligands. Studies in cancer cell lines indicated in general that the complexes with the largest dipole moments exhibited the highest antiproliferative activity in comparison with structurally closely related complexes. Thus, complexes 5f, (with 4-fluoroethynylbenzene as alkynyl precursor), and 6b, (with mestranol as alkynyl precursor) containing the same methoxy‑substituted NHC ligand showed in general the strongest biological activity. Protein binding studies confirmed a high affinity to albumin (around 90 %) and cellular uptake studies indicated an increased uptake of the most active complex 5f
Urban Meteorology, Pollutants, Geomorphology, Fractality, and Anomalous Diffusion
No full textPublisher Copyright: © 2024 by the authors.The measurements, recorded as time series (TS), of urban meteorology, including temperature (T), relative humidity (RH), wind speed (WS), and pollutants (PM10, PM2.5, and CO), in three different geographical morphologies (basin, mountain range, and coast) are analyzed through chaos theory. The parameters calculated at TS, including the Lyapunov exponent (λ > 0), the correlation dimension (DC 0), the Hurst exponent (0.5 0), the loss of information ( < 0), and the fractal dimension (D), show that they are chaotic. For the different locations of data recording, CK is constructed, which is a proportion between the sum of the Kolmogorov entropies of urban meteorology and the sum of the Kolmogorov entropies of the pollutants. It is shown that, for the three morphologies studied, the numerical value of the CK quotient is compatible with the values of the exponent α of time t in the expression of anomalous diffusion applied to the diffusive behavior of atmospheric pollutants in basins, mountain ranges, and coasts. Through the Fréchet heavy tail study, it is possible to define, in each morphology, whether urban meteorology or pollutants exert the greatest influence on the diffusion processes