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Ordered Patterns of (3+1)-Dimensional Hadronic Gauged Solitons in the Low-Energy Limit of Quantum Chromodynamics at a Finite Baryon Density, Their Magnetic Fields and Novel BPS Bounds
No full textPublisher Copyright: © 2024 by the authors.In this paper, we will review two analytical approaches to the construction of non-homogeneous Baryonic condensates in the low-energy limit of QCD in (3+1) dimensions. In both cases, the minimal coupling with the Maxwell (Formula presented.) gauge field can be taken explicitly into account. The first approach (which is related to the generalization of the usual spherical hedgehog ansatz to situations without spherical symmetry at a finite Baryon density) allows for the construction of ordered arrays of Baryonic tubes and layers. When the minimal coupling of the Pions to the (Formula presented.) Maxwell gauge field is taken into account, one can show that the electromagnetic field generated by these inhomogeneous Baryonic condensates is of a force-free type (in which the electric and magnetic components have the same size). Thus, it is natural to wonder whether it is also possible to analytically describe magnetized hadronic condensates (namely, Hadronic distributions generating only a magnetic field). The idea of the second approach is to construct a novel BPS bound in the low-energy limit of QCD using the theory of the Hamilton–Jacobi equation. Such an approach allows us to derive a new topological bound which (unlike the usual one in the Skyrme model in terms of the Baryonic charge) can actually be saturated. The nicest example of this phenomenon is a BPS magnetized Baryonic layer. However, the topological charge appearing naturally in the BPS bound is a non-linear function of the Baryonic charge. Such an approach allows us to derive important physical quantities (which would be very difficult to compute with other methods), such as how much one should increase the magnetic flux in order to increase the Baryonic charge by one unit. The novel results of this work include an analysis of the extension of the Hamilton–Jacobi approach to the case in which Skyrme coupling is not negligible. We also discuss some relevant properties of the Dirac operator for quarks coupled to magnetized BPS layers
Diseño de un sistema de gestión y administración de personal para el departamento de post venta de la empresa PV EQUIP S.A.
Get PDFPV Equip S.A. es una empresa representante y distribuidora de equipos médicos establecida en Chile desde 1989, con oficina central en Santiago, cuyo foco principal es entregar soluciones tecnológicas para el mercado de la salud en Chile. Es una empresa con una gran presencia en el mercado a través de sus marcas representadas, en donde podemos mencionar a GE Healthcare (antigua división de salud de General Electric), Maquet, Zoll Medical, Masimo, entre otras. Está considerada dentro de las empresas de tamaño mediano, con un equipo humano de 131 colaboradores, lo que le permite atender necesidades del área de la salud a lo largo de todo Chile, desde Arica a Puerto Williams. Como empresa distribuidora de tecnología de alta complejidad, y que tiene como principales clientes a Hospitales y Clínicas a lo largo del país, un foco importante de su operación está puesto en su gerencia de post venta, gerencia que tiene dentro de sus actividades principales cumplir con todos los temas técnicos asociados a los equipos, tanto para temas preventivos como correctivos. A lo largo de su trayectoria, y a través de su gerencia de post venta PV Equip ha logrado establecer una gran relación con sus clientes, esto sustentado por el nivel de cumplimiento en los compromisos establecidos y tiempos de respuesta asociados a los temas técnicos del equipamiento, aunque de todas formas no es un camino exento de problemas y que debe mantener una visión de mejora continua para no estancarse e ir de la mano con las nuevas exigencias que vayan presentando los clientes. Esta propuesta apunta a ser un aporte relacionado con la gestión del personal técnico de PV Equip, apuntando principalmente a temas de programación de tareas, distribución de las actividades u otros elementos asociados a la organización de las personas que ejecutan los trabajos de mantención correctiva y preventiva en terreno. Además de analizar las potenciales causas que generan una distribución ineficiente de los técnicos a la hora de programar las actividades, también se entregan algunas propuestas de mejora, desde el punto de vista de la ingeniería, que aportan directamente a la empresa tanto de un punto de vista económico, como también para el cumplimiento de los objetivos que existen hacia los clientes.PV Equip S.A. is a medical equipment representative and distributor company established in Chile since 1989, with headquarters in Santiago, whose focus is to deliver technological solutions for the health market in Chile. It is a company with a great presence in the market through its represented brands, where we can mention GE Healthcare (former health division of General Electric), Maquet, Zoll Medical, Masimo, among others. It is considered among medium-sized companies, with a team of 131 employees, which allows it to meet needs in the health area throughout Chile, from Arica to Puerto Williams. As a highly complex technology distribution company, and whose main customers are Hospitals and Clinics throughout the country, an important focus of its operation is placed on its aftersales management, management that has among its main activities to comply with all the technical issues associated with the equipment, both for preventive and corrective issues. Throughout its history, and through its after-sales management, PV Equip has managed to establish a great relationship with its customers, this is supported by the level of compliance with the established commitments and response times associated with the technical issues of the equipment, although in any case it is not a path without problems and that must maintain a vision of continuous improvement so as not to stagnate and go from the hand in hand with the new demands that customers present. This proposal aims to be a contribution related to the management of PV Equip's technical staff, aiming at issues of task scheduling, distribution of activities or other elements associated with the organization of the people who conduct corrective and preventive maintenance work in the field. In addition to analyzing the potential causes that generate an inefficient distribution of technicians when scheduling activities, some proposals for improvement are also delivered, from the point of view of engineering, which contribute directly to the company both from an economic point of view, and for the fulfillment of the objectives that exist towards customers
Repensando el mito de origen de la arquitectura en América. El ejemplo de Chile
No full textEl siguiente artículo, indaga sobre el lugar desde donde se sitúa la historia oficial de la arquitectura en el continente americano a partir de la idea de la cabaña primitiva como mito fundacional. Utilizando el caso de Chile como ejemplo, se plantea la inexistencia en los relatos que buscan dar con el origen a las arquitecturas nacionales de las preexistencias construidas de los pueblos originarios que habitaban los territorios previo a la llegada de los conquistadores españoles. A modo de propuesta, se hace un paralelo desde el relato del surgimiento simbólico de la arquitectura en el mundo occidental, con las características y relevancias de algunos ejemplos de patrimonio vernáculo construido indígena en Chile. Así, buscamos hacer una reflexión que posibilite un cambio en los referentes discursivos fundantes de la arquitectura en nuestro continente
Uso de midazolam intranasal en crisis epilépticas en perros (canis lupus familiaris) : revisión bibliográfica
No full textLa epilepsia es un síndrome que reúne una serie de signos que se manifiestan en un cuadro convulsivo, que son manifestaciones transitorias causadas por actividad neuronal anormal. La rapidez para detener las convulsiones se relaciona con la gravedad del daño neurológico que se pueda generar. En emergencias, las benzodiazepinas son usadas como tratamiento para detener las convulsiones, siendo el Diazepam intrarrectal el más utilizado como tratamiento, pero sus limitaciones han generado la búsqueda de alternativas más accesibles y fácil administración. Una de las opciones es el Midazolam intranasal, con las ventajas que proporciona la absorción nasal, permite una rápida absorción y penetración a través la barrera hematoencefálica. Es por esto, que vista la urgencia que significan las crisis epilépticas y los distintos problemas asociados a los tratamientos y vías de administración usados para su cese y las ventajas que ofrecería la administración intranasal de Midazolam frente a otros tratamientos y sus vías de aplicación, se plantea la interrogante ¿Es efectivo el uso de Midazolam intranasal como terapia de rescate en crisis epilépticas? Esta revisión tuvo como objetivo la fundamentación del uso de Midazolam intranasal en crisis epilépticas en perros, la cual se realizó a través de la lectura de artículos científicos que tienen relación con los tratamientos de primera línea y el uso de Midazolam intranasal, los cuales fueron encontrados en las bases de datos ProQuest, Web of Science y Science Direct, metabuscador Pubmed y motor de búsqueda Google académico que no superaran la ventana temporal entre los años 2010 a 2024. Se realizó la recopilación de información y finalmente la selección del material que se incluyó en esta revisión con el fin de fundamentar el uso extrahospitalario de Midazolam intranasal en crisis epilépticas en perros, la cual fue ordenada mediante tablas en las cuales se agruparon los datos según los siguientes aspectos: buscador, año de publicación, autor(es), tipo de estudio, peso bibliográfico y factor de impacto y los resultados de estos fueron ordenados en tablas según los parámetros utilizados. En los estudios se describió una tasa de éxito sobre el 50% en detener las convulsiones y un tiempo de cese inferior a un minuto, así como una mayor facilidad en la aplicación y menor tiempo de preparación del producto. Se destaca la administración intranasal del Midazolam como una opción práctica debido a su facilidad de aplicación y a la rápida acción, especialmente útil en casos extrahospitalarios. Se recomienda el uso de Midazolam intranasal como una alternativa más eficaz y segura en ciertos contextos hospitalarios y extra-hospitalarios.Epilepsy is a syndrome that brings together a series of signs that manifest themselves in a convulsive picture, which are transient manifestations caused by abnormal neuronal activity. The speed at which seizures are stopped is related to the severity of the neurological damage that may be generated. In emergencies, benzodiazepines are used as treatment to stop seizures, being the intrarectal Diazepam the most used as treatment, but its limitations have generated the search for more accessible and easy administration alternatives. One of the options is intranasal Midazolam, with the advantages of nasal absorption, allowing rapid absorption and penetration through the blood-brain barrier. Therefore, given the urgency of epileptic seizures and the different problems associated with the treatments and routes of administration used for their cessation and the advantages offered by intranasal administration of Midazolam compared to other treatments and their routes of application, the question arises: Is the use of intranasal Midazolam effective as rescue therapy in epileptic seizures? This review aimed at substantiating the use of intranasal Midazolam in epileptic seizures in dogs, which was done through the reading of scientific articles related to first-line treatments and the use of intranasal Midazolam, which were found in the ProQuest, Web of Science and Science Direct databases, Pubmed meta-search engine and Google academic search engine that did not exceed the time window between 2010 and 2024. The collection of information and finally the selection of the material to be included in this review was carried out in order to support the out-of-hospital use of intranasal Midazolam in epileptic seizures in dogs, which was sorted by tables in which the data were grouped according to the following aspects: search engine, year of publication, author(s), type of study, bibliographic weight and impact factor and the results of these were sorted in tables according to the parameters used. The studies described a success rate of over 50% in stopping seizures and a cessation time of less than one minute, as well as greater ease of application and shorter product preparation time. Intranasal administration of Midazolam is highlighted as a practical option due to its ease of application and rapid action, especially useful in out-of-hospital cases. The use of intranasal Midazolam is recommended as a more effective and safer alternative in certain hospital and out-of-hospital contexts
Electric corrections to π-π scattering lengths in the linear sigma model
No full textPublisher Copyright: © 2024 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.In this article, we analyze the role of an external electric field, in the weak field approximation, on π-π scattering lengths. The discussion is presented in the frame of the linear sigma model. To achieve this, we take into account all one-loop corrections in the s, t, and u channels associated with the insertion of a Schwinger propagator for charged pions, focusing on the region characterized by small values of the electric field. Furthermore, one of the novelties of our work is the explicit calculation of box diagrams, which were previously overlooked in discussions regarding magnetic corrections. It turns out that the electric field corrections have an opposite effect with respect to magnetic corrections calculated previously in the literature
Brain clocks capture diversity and disparities in aging and dementia across geographically diverse populations
No full textPublisher Copyright: © The Author(s) 2024.Brain clocks, which quantify discrepancies between brain age and chronological age, hold promise for understanding brain health and disease. However, the impact of diversity (including geographical, socioeconomic, sociodemographic, sex and neurodegeneration) on the brain-age gap is unknown. We analyzed datasets from 5,306 participants across 15 countries (7 Latin American and Caribbean countries (LAC) and 8 non-LAC countries). Based on higher-order interactions, we developed a brain-age gap deep learning architecture for functional magnetic resonance imaging (2,953) and electroencephalography (2,353). The datasets comprised healthy controls and individuals with mild cognitive impairment, Alzheimer disease and behavioral variant frontotemporal dementia. LAC models evidenced older brain ages (functional magnetic resonance imaging: mean directional error = 5.60, root mean square error (r.m.s.e.) = 11.91; electroencephalography: mean directional error = 5.34, r.m.s.e. = 9.82) associated with frontoposterior networks compared with non-LAC models. Structural socioeconomic inequality, pollution and health disparities were influential predictors of increased brain-age gaps, especially in LAC (R² = 0.37, F² = 0.59, r.m.s.e. = 6.9). An ascending brain-age gap from healthy controls to mild cognitive impairment to Alzheimer disease was found. In LAC, we observed larger brain-age gaps in females in control and Alzheimer disease groups compared with the respective males. The results were not explained by variations in signal quality, demographics or acquisition methods. These findings provide a quantitative framework capturing the diversity of accelerated brain aging
El Santo Rosario: un puente entre lo terrenal y lo espiritual a largo de la historia
No full textEl presente estudio nos da a conocer la evolución histórica que ha tenido el Santo Rosario en la Iglesia Católica, desde sus inicios como devoción mariana, pasando por quienes le destacaron en distintas épocas, hasta las cartas y encíclicas que han sido levantadas por diferentes pontífices que invitan a su rezo, destacando los beneficios espirituales que conlleva la práctica constante de este
LA CONFLICTIVIDAD EN EL USO DE LAS AGUAS SERVIDAS TRATADAS EN LA CUENCA DEL MAIPO-MAPOCHOUNA PERSPECTIVA DESDE LA ESCASEZ HÍDRICA
No full textPublisher Copyright: © (2024), (SciELO-Scientific Electronic Library Online). All Rights Reserved.We analyze the existing conflict between farmers and drinking water companies around the property of treated wastewater that is evacuated to the Mapocho river, product of the supply and sanitation of the city of Santiago, and that is used by the irrigators that are located downstream of the discharge points of the treatment plants. The conflict warned here now has a new element: a regulatory framework that, from the year 2022, establishes a priority in the use of water for human consumption and sanitation, distorting the equitable redistribution of water resources in times of drought
Is It Possible to Improve the Perceived Quality of Life of Overweight or Obese Older People through a Multicomponent Physical Exercise Program?
No full textCo-ocurrencia de dos plásmidos que codifican genes transferibles blaNDM-1 y tet(Y) en Acinetobacter bereziniae resistente a carbapenémicos.
No full textPublisher Copyright: © 2024 by the authors.Acinetobacter bereziniae has emerged as a significant human pathogen, acquiring multiple antibiotic resistance genes, including carbapenemases. This study focuses on characterizing the plasmids harboring the blaNDM-1 and tet(Y) genes in two carbapenem-resistant A. bereziniae isolates (UCO-553 and UCO-554) obtained in Chile during the COVID-19 pandemic. Methods: Antibiotic susceptibility testing was conducted on UCO-553 and UCO-554. Both isolates underwent whole-genome sequencing to ascertain their sequence type (ST), core genome multilocus sequence-typing (cgMLST) profile, antibiotic resistance genes, plasmids, and mobile genetic elements. Conjugation experiments were performed for both isolates. Results: Both isolates exhibited broad resistance, including resistance to carbapenems, third-generation cephalosporins, fluoroquinolones, tetracycline, cotrimoxazole, and aminoglycosides. Both isolates belong to sequence type STPAS1761, with a difference of 17 out of 2984 alleles. Each isolate carried a 47,274 bp plasmid with blaNDM-1 and aph(3′)-VI genes and two highly similar plasmids: a 35,184 bp plasmid with tet(Y), sul2, aph(6)-Id, and aph(3″)-Ib genes, and a 6078 bp plasmid containing the ant(2″)-Ia gene. Quinolone-resistance mutations were identified in the gyrA and parC genes of both isolates. Importantly, blaNDM-1 was located within a Tn125 transposon, and tet(Y) was embedded in a Tn5393 transposon. Conjugation experiments successfully transferred blaNDM-1 and tet(Y) into the A. baumannii ATCC 19606 strain, indicating the potential for horizontal gene transfer. Conclusions: This study highlights the critical role of plasmids in disseminating resistance genes in A. bereziniae and underscores the need for the continued genomic surveillance of this emerging pathogen. The findings emphasize the importance of monitoring A. bereziniae for its potential to cause difficult-to-treat infections and its capacity to spread resistance determinants against clinically significant antibiotics.Acinetobacter bereziniae has emerged as a significant human pathogen, acquiring multiple antibiotic resistance genes, including carbapenemases. This study focuses on characterizing the plasmids harboring the blaNDM-1 and tet(Y) genes in two carbapenem-resistant A. bereziniae isolates (UCO-553 and UCO-554) obtained in Chile during the COVID-19 pandemic. Methods: Antibiotic susceptibility testing was conducted on UCO-553 and UCO-554. Both isolates underwent whole-genome sequencing to ascertain their sequence type (ST), core genome multilocus sequence-typing (cgMLST) profile, antibiotic resistance genes, plasmids, and mobile genetic elements. Conjugation experiments were performed for both isolates. Results: Both isolates exhibited broad resistance, including resistance to carbapenems, third-generation cephalosporins, fluoroquinolones, tetracycline, cotrimoxazole, and aminoglycosides. Both isolates belong to sequence type STPAS1761, with a difference of 17 out of 2984 alleles. Each isolate carried a 47,274 bp plasmid with blaNDM-1 and aph(3′)-VI genes and two highly similar plasmids: a 35,184 bp plasmid with tet(Y), sul2, aph(6)-Id, and aph(3″)-Ib genes, and a 6078 bp plasmid containing the ant(2″)-Ia gene. Quinolone-resistance mutations were identified in the gyrA and parC genes of both isolates. Importantly, blaNDM-1 was located within a Tn125 transposon, and tet(Y) was embedded in a Tn5393 transposon. Conjugation experiments successfully transferred blaNDM-1 and tet(Y) into the A. baumannii ATCC 19606 strain, indicating the potential for horizontal gene transfer. Conclusions: This study highlights the critical role of plasmids in disseminating resistance genes in A. bereziniae and underscores the need for the continued genomic surveillance of this emerging pathogen. The findings emphasize the importance of monitoring A. bereziniae for its potential to cause difficult-to-treat infections and its capacity to spread resistance determinants against clinically significant antibiotics