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Estudio de prefactibilidad técnico y económico para la comercialización de una aplicación móvil para varios restaurants de Santiago de Chile
No full textEl presente estudio tiene como finalidad el determinar la factibilidad estratégica,
técnica y económica de la creación la comercialización de una aplicación móvil
destinada a facilitar la división de cuentas en bares y restobares en Santiago de
Chile. Actualmente, salir a estos establecimientos es una actividad social muy
apreciada, pero la gestión de pagos grupales presenta inconvenientes,
generando tensiones entre los comensales y afectando la eficiencia del servicio.
El crecimiento del uso de aplicaciones móviles en el sector de alimentos y
bebidas en Chile refleja un mercado en expansión, aunque muchos locales aún
no adoptan soluciones tecnológicas para optimizar estos procesos.
La propuesta de la aplicación busca resolver estos problemas al proporcionar un
sistema que conecte a múltiples usuarios y al personal de servicio, facilitando la
división de cuentas en tiempo real y reduciendo la incertidumbre y conflictos
asociados. Desde un punto de vista económico, el análisis financiero muestra
que el proyecto es viable con diversas formas de financiamiento, presentando un
Valor Actual Neto (VAN) y una Tasa Interna de Retorno (TIR) positivos. Esto
respalda su factibilidad como una inversión atractiva y con proyección de éxito
en un nicho de mercado con alto potencial de crecimiento y desarrollo.
La comercialización de esta aplicación móvil no solo es viable desde una
perspectiva técnica y económica, sino que también representa una oportunidad
innovadora para mejorar la experiencia en bares y restobares, con una
proyección favorable para su implementación en el mercado chileno.The purpose of this study is to determine the strategic, technical and economic
feasibility of creating and marketing a mobile application intended to facilitate
the division of accounts in bars and restobars in Santiago, Chile. Currently,
leaving these establishments is a highly appreciated social activity, but the
management of group payments presents inconveniences, generating tensions
between diners and affecting the efficiency of the service. The growth in the use
of mobile applications in the food and beverage sector in Chile reflects an
expanding market, although many establishments have not yet adopted
technological solutions to optimize these processes.
The application proposal seeks to solve these problems by providing a system
that connects multiple users and service personnel, facilitating the division of
accounts in real time and reducing the uncertainty and associated conflicts.
From an economic point of view, the financial analysis shows that the project is
viable with various forms of financing, presenting a positive Net Present Value
(NPV) and Internal Rate of Return (IRR). This supports its feasibility as an
attractive investment with a projection of success in a market niche with high
potential for growth and development.
The commercialization of this mobile application is not only viable from a
technical and economic perspective, but also represents an innovative
opportunity to improve the experience in bars and restaurants, with a favorable
projection for its implementation in the Chilean market
Clones reactive to apoptotic cells and specific chemical adducts are prevalent among human thymic B cells
No full textPublisher Copyright: Copyright © 2024 Hertel, Aguiar, Mashiko, Núñez, Moore, Gao, Ausmeier, Roy and Zorn.Introduction: Thymus resident B cells were described more than 40 years ago. In early human life, these cells are found predominantly in the medulla and overwhelmingly display an unswitched IgM+ phenotype. The reactivity of thymic IgM B cells, however, is still unclear. Methods: Here, we generated 120 IgM-producing B cell clones from 3 separate thymus specimens obtained from infant, adolescent, and adult donors. Using flow cytometry and a unique high-dimensional ELISA platform, we investigated the clones’ reactivity to apoptotic cells as well as to common chemical adducts exposed on modified amino acids and other macromolecules. Results: Regardless of the age, approximately 30-40% of thymic IgM B cells reacted to apoptotic cells. Further, 30-40% displayed reactivity to at least one adduct, including malondialdehyde, Homocysteine, and NEDD 8. Four distinct reactivity patterns were identified through this profiling. Notably, a significant association was observed between reactivity to apoptotic cells, and to one or more adducts, suggesting that the same determinants were recognized in both assays. Additionally, thymic IgM B cells reactive to adducts were more likely to recognize intra-nuclear or intra-cytoplasmic structures in Hep-2 cells as revealed by immunofluorescence staining. Conclusion/Discussion: Collectively, our findings suggest that thymic IgM B cells actively uptake apoptotic bodies and cellular debris in the medulla by binding specific chemical adducts. This mechanism could underpin their antigen-presenting function and further support their role in T-cell negative selection
Fast FCS-MPC for neutral-point clamped converters with switching constraints
No full textPublisher Copyright: © 2024 Elsevier LtdModel Predictive Control algorithms have been recently developed for controlling grid-tied converters. However, the inclusion of the converter switching constraints in the optimization problem and the high computational burden are some of the main challenges of these algorithms. In this way, this paper proposes a Fast Finite Control Set Model Predictive Control algorithm with a low computational burden for a three-phase Neutral Point Clamped inverter considering its switching constraints. Initially, the vector with the unconstrained solution in the line-to-line voltage coordinates is obtained to minimize the current tracking error. Then, it is limited to ellipses as an intermediate step to ensure that the selected voltage vector is feasible and to restrict the switching transitions. The constrained vector is rounded to the nearest inverter line-to-line voltage vector to be implemented in the next sampling period. The NPC redundant phase-voltage vectors are generated online to avoid the potentially destructive switching transitions. The neutral point is balanced by minimizing a cost function, considering the obtained redundant phase voltage vectors, and is evaluated at most twice in each sampling period. As both control objectives are treated in a cascaded sequence, the proposed Fast FCS-MPC avoids the design of weighting factors and has the advantages of low computational burden, fast transient response, and good steady-state performance. Finally, Hardware-in-the-Loop results are presented to compare the proposed Fast FCS-MPC to other strategies presented in the literature, and the effectiveness of the proposed algorithm is also demonstrated by means of an experimental prototype
Navigating job satisfaction in family firms during crisis
No full textPublisher Copyright: Copyright © 2024 Ibañez, Andrade-Valbuena and Llanos-Contreras.Occupational health is one of the aspects significantly affected during crisis periods. It is essential to learn about the factors that improve organizational capacity in coping with such shocks. This study investigates how the working environment of a family business influences job satisfaction during crises. Conducting a survey with 516 employees at the peak of the pandemic, the research utilizes structural equation analysis, revealing that family business environments can mitigate burnout, enhance affective commitment, and consequently, boost job satisfaction. The study highlights the need to manage burnout and utilize resources, such as employee commitment, for family firms to sustain job satisfaction amidst disruptions. It deepens the comprehension of family businesses’ crisis response, emphasizing the significance of human resource commitment and management. The investigation illuminates the dynamic interplay between the work environment, employee well-being, and organizational resilience, providing valuable insights for both theoretical understanding and practical application
Which fits better?. Centered and non-Centered coordination modes of small endohedral Fullerenes, insights from Ti@C28 and Zr@C28
No full textPublisher Copyright: © 2024 Elsevier B.V.The endohedral metallic fullerenes (EMF), exhibit the interplay between stabilizing interaction and steric hindrance effects owing to the internal size provided by the fullerene cage. The small C 28 fullerene, offers the smallest cavity realized to encapsulate metal ions. The characterized energy minima structure for Ti@C 28 exhibits a non-centered disposition of the Ti atom in a spherical cage, in contrast to Zr@C 28, where Zr atom is located at the very center. Here, we explore variations of the 3d-Ti-π-C 28 bonding interaction from a centered conformation towards the non-centered disposition in comparison to Zr@C 28. Our results show that in such structures, a variation of both electrostatic and orbital character of the metal-cage interaction can be observed. Interestingly, the orbital term is largely favored underlying the more effective bonding in the latter conformation, playing a crucial role in the determination of the coordination mode. In addition, molecular dynamics simulations were employed to determine the endohedral atom variation at 300°K, denoting that Zr@C 28 cage exhibits more structural variation in comparison to Ti@C 28, owing to the movement of a more fitted metal center induces larger variations to the cage distance
Avances en la neuropatogénesis y neurodegeneración del distemper canino : revisión bibliográfica
Get PDFEl virus del distemper canino (VDC) es un patógeno altamente contagioso causante del moquillo canino, una enfermedad neurológica grave en canidos. Las variedades de resultados en la infección por VDC, se deben a la interacción entre el virus y las células del sistema inmune. La presente revisión bibliográfica realizada es de tipo tradicional enfocada en los descubrimientos recientes de neurodegeneración y neuropatogénesis del VDC. Para ello, se implementó una estrategia de búsqueda en bases de datos disponibles en la biblioteca de la Universidad San Sebastián tales como: Medline, Scielo, Research gate, Metabuscador PUBMED y motores de búsqueda como Google Académico. Avances en la investigación de la etiopatogenia del VDC determino que la ruta de entrada más frecuente es la hematógena propagándose a través del LCR en las distintas estructuras cerebrales. La neuropatogenia reciente identificó receptores de interacción con el VDC tales como: SLAM, Nectina-4 y un tercer receptor que hasta hace poco constituía una incógnita, denominado GliaR, que permite la propagación viral intracerebral. La lesión desmielinizante se resumió en tres mecanismos que de manera simultánea actúan sobre los astrocitos, principal célula-objetivo del virus en su propagación y persistencia. Factores patogénicos asociados también participan del proceso: AQP4, enzima GS, polarización astrocítica fenotipo A1 y sobreexpresión de Survinina, que junto a una desregulación inmunológica proinflamatoria generan la enfermedad neurológica desmielinizante. La presente revisión concluye, que la neuropatogénesis neuronal con el desarrollo de complejos procesos proinflamatorios moleculares junto al acción neurodegenerativa de los astrocitos establecen la injuria desmielinizante observada.Canine Distemper virus (CDV) is a highly contagious pathogen that causes canine distemper, a serious neurological disease in canines. The variety of outcomes in DCV infection are due to the interaction between the virus and the cells of the immune system. The present bibliographic review carried out is of a traditional type focused on recent discoveries of neurodegeneration and neuropathogenesis of VDC. To do this, a search strategy was implemented in databases available in the San Sebastián University library such as: Medline, Scielo, Research gate, PUBMED Metasearch engine and search engines such as Google Scholar. Advances in research into the etiopathogenesis of CDV determined that the most frequent route of entry is hematogenous, spreading through the CSF in the different brain structures. Recent neuropathogenesis identified receptors that interact with the VDC such as: SLAM, Nectin-4 and a third receptor that until recently was unknown, called GliaR, which allows intracerebral viral spread. The demyelinating lesion was summarized in three mechanisms that simultaneously act on astrocytes, the main target cell of the virus in its spread and persistence. Associated pathogenic factors also participate in the process: AQP4, GS enzyme, astrocytic polarization phenotype A1 and overexpression of Survinin, which together with a proinflammatory immune deregulation generate the demyelinating neurological disease. The present review concludes that neuronal neuropathogenesis with the development of complex molecular proinflammatory processes together with the neurodegenerative action of astrocytes establishes the observed demyelinating injury
Evaluation of Fissures and Cracks in Bridges by Applying Digital Image Capture Techniques Using an Unmanned Aerial Vehicle
No full textPublisher Copyright: © 2023 by the authors.The evaluation of cracks and fissures in bridge structures is essential to ensure the long-term safety, durability, and functionality of these infrastructures. In this sense, processing grayscale images and adjusting brightness and contrast levels can improve the visibility of cracks and fissures in bridge structures. These techniques, complemented by professional expertise and efficient inspection tools such as Unmanned Aerial Vehicles (UAVs), allow for a comprehensive and accurate structural integrity assessment. This study used the edge detection technique to analyze photographs obtained with a low-cost UAV as a means of image capture. This tool was used to reach hard-to-reach areas where there could be damage, thus making it easier to detect fissures or cracks. To capture the failures, two case studies, a small bridge and a large bridge, were selected, both located in Concepción City in southern Chile. During both inspections, cracks were detected that could affect the structure of the bridges in the future. To analyze these findings, ImageJ software 1.54h was used, which allowed the length and thickness of the cracks to be measured and evaluated. In addition, to validate the procedure proposed, real values manually measured on-site were compared with those delivered by the software analyses, where no statistically significant differences were found. With the method presented in this study, it was possible to quantify the damage, following the bridge maintenance standards established by the Ministry of Public Works of Chile, whose inspection criteria can be applied to other projects worldwide
Adaptación y Validación de la Escala de Percepción de inequidad económica en la vida cotidiana
No full textPublisher Copyright: © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.The Perceived Economic Inequality in Everyday Life (PEIEL) scale was developed in Spain within the context of political and social psychology research. This study introduces an abbreviated version of the scale for potential application in health research among the Chilean population. This study examined the psychometric properties of the proposed adaptation and assessed its metric invariance across lower and higher income groups in a sample of Chilean adults aged 50 and older (n = 372 respondents; 64.1% women; mean age ± SD = 58.8 ± 5.2). Four experts reviewed the original scale items to create a shortened version, selecting those that effectively capture economic inequality in the Chilean context. Confirmatory factor analysis was employed to validate the proposed factorial structure and assess invariance. The results support the proposed factorial structure and establish scalar invariance, which indicates the instrument’s consistent measurement properties across income levels
4’–phenyl -2, 2’: 6’, 2’’-terpyridine Derivatives as Metal Chemosensors. Chelation and Fluorescence Capabilities Towards Zn(II), Cd(II), and Hg(II) From Experiment and Theory.
No full textBeing a black woman in the Chilean Academy. Tensions and reflectionsInterview with Luz Valoyes Chávez
No full textEntrevista realizada a la académica Luz Valoyes Chávez. Indaga sobre el racismo en la academica y las limitantes de producción de conocimiento de personas negras desde la experiencia de la entrevistada. Se realiza en sesiones de conversación y se presenta en base a cuatro preguntas que organizan el discurso. Se busca sensibilizar y derribar las dinámicas de violencia racial presentes en la producción de conocimiento en las universidades