Propuesta de metodología para el análisis exergético de una turbina a gas de ciclo simple

El análisis exergético de una turbina a gas permite la evaluación individual de sus componentes, hallando así la destrucción de exergía y la eficiencia exergética de cada uno de estos. Partiendo de esta premisa, esta tesis presenta una sólida base teórica que explora el funcionamiento de este equipo y se adentra en la Primera y la Segunda Ley de la Termodinámica, con la finalidad de proponer una metodología para realizar un análisis exergético a una turbina a gas. Para cumplir este objetivo, primero se revisa las características de una turbina a gas desde un punto de vista mecánico y termodinámico, para luego describir el marco teórico bajo el cual se desarrollan los análisis energético y exergético. Una vez planteados, esta tesis aplica la metodología a la turbina a gas marca Rover del Laboratorio de Energía de la PUCP. Finalmente, para validar la metodología, se analiza los resultados y posteriormente estos se contrastan con trabajos similares, a fin de revisar la consistencia de los mismos. Los resultados obtenidos en este trabajo determinan que se puede evaluar los flujos de exergía del equipo. La máxima destrucción de exergía se da en la cámara de combustión. En el caso de la turbina evaluada, esta representa el 56% de la exergía total destruida, componente en el cual también se obtiene la peor eficiencia exergética, que solo asciende al 51%, en comparación con los otros componentes de la turbina que bordean el 90%. Del mismo modo, se establece que, como producto del ciclo Brayton simple bajo el cual opera la turbina, la destrucción de la exergía de los gases de combustión al ser liberados al ambiente representa una importante pérdida que ocupa el segundo lugar, y que en el caso de la turbina evaluada llega a más del 30% de exergía destruida.Tesi

Not all stressors are equal : behavioral and endocrine evidence for development of contextual fear conditioning after a single session of footshocks but not of immobilization

Exposure of animals to footshocks (FS) in absence of any specific cue results in the development of fear to the compartment where shocks were given (contextual fear conditioning), and this is usually evaluated by time spent freezing. However, the extent to which contextual fear conditioning always develops when animals are exposed to other stressors is not known. In the present work we firstly demonstrated, using freezing, that exposure of adult rats to a single session of FS resulted in short-term and long-term contextual fear conditioning (freezing) that was paralleled by increased hypothalamic-pituitary-adrenal (HPA) activation. In contrast, using a similar design, no HPA or behavioral evidence for such conditioning was found after exposure to immobilization on boards (IMO), despite this stressor being of similar severity as FS on the basis of standard physiological measures of stress, including HPA activation. In a final experiment we directly compared the exposure to the two stressors in the same type of context and tested for the development of conditioning to the context and to a specific cue for IMO (the board). We observed the expected high levels of freezing and the conditioned HPA activation after FS, but not after IMO, regardless of the presence of the board during testing. Therefore, it can be concluded that development of fear conditioning to context or particular cues, as evaluated by either behavioral or endocrine measures, appears to be dependent on the nature of the aversive stimuli, likely to be related to biologically preparedness to establish specific associations

Epigenetic mechanisms during ageing and neurogenesis as novel therapeutic avenues in human brain disorders

Ageing is the main risk factor for human neurological disorders. Among the diverse molecular pathways that govern ageing, epigenetics can guide age-associated decline in part by regulating gene expression and also through the modulation of genomic instability and high-order chromatin architecture. Epigenetic mechanisms are involved in the regulation of neural differentiation as well as in functional processes related to memory consolidation, learning or cognition during healthy lifespan. On the other side of the coin, many neurodegenerative diseases are associated with epigenetic dysregulation. The reversible nature of epigenetic factors and, especially, their role as mediators between the genome and the environment make them exciting candidates as therapeutic targets. Rather than providing a broad description of the pathways epigenetically deregulated in human neurological disorders, in this review, we have focused on the potential use of epigenetic enzymes as druggable targets to ameliorate neural decline during normal ageing and especially in neurological disorders. We will firstly discuss recent progress that supports a key role of epigenetic regulation during healthy ageing with an emphasis on the role of epigenetic regulation in adult neurogenesis. Then, we will focus on epigenetic alterations associated with ageing-related human disorders of the central nervous system. We will discuss examples in the context of psychiatric disorders, including schizophrenia and posttraumatic stress disorders, and also dementia or Alzheimer's disease as the most frequent neurodegenerative disease. Finally, methodological limitations and future perspectives are discussed.EU Joint Programme-Neurodegenerative Disease Research (JPND; EPI-AD Consortium)RecerCaixa Foundation, Federación Española de Enfermedades Raras (FEDER)Federación Española de Enfermedades Neuromusculares (ASEM)Fundación Isabel GemioAsociación Española Contra el Cáncer (AECC)Ministerio de Sanidad, Servicios Sociales e Igualda

Crowdfunding como herramienta estratégica para la gestión sostenible de iniciativas culturales : plataforma virtual de crowdfunding con base en eventos musicales en la ciudad de Lima

En los últimos años se ha venido incrementando la valoración de las organizaciones, independientemente de su sector, por la innovación y su contribución como fuente de ventaja competitiva. Ante tal situación, han surgido diversos modelos de negocio en los cuales se intenta transponer elementos de los modelos ya existentes e innovar en función a esto. Un claro ejemplo de esto, es el crowdfunding como modelo de negocio que concentra elementos del financiamiento masivo y el trabajo colectivo como fuentes de creación de valor. Las industrias culturales por otro lado, contienen dentro de ellas una percepción de riesgo alto, donde el financiamiento tradicional no suele apostar y el núcleo creativo no se encuentra conectado con factores como la tecnología y la gestión. Hacer una convergencia de un modelo de negocio como crowdfunding que postula una inversión de bajo riesgo con una industria como la musical que se encuentra dentro de las industrias culturales no es tarea fácil pero ciertamente, rompe paradigmas acerca de que la cultura y sus componentes no son rentables. La investigación de este proyecto profesional busca ir más allá de lo establecido como rentable y no rentable e introducir en la ciudad de Lima el modelo de financiamiento alternativo como crowdfunding, dotándolo de características que mezclan planeamiento estratégico principalmente para la sostenibilidad de los eventos musicales dentro de la industria musical, postulándolo como herramienta estratégica y como elemento de plan de marketing que cualquiera del núcleo creativo de este sector debería considerar. La investigación de carácter cualitativo va desde los casos internacionales de las páginas más exitosas de crowdfunding y lo que se encuentra existente en el Perú en un estado incipiente pero con potencial a descubrir y explotar; hasta las entrevistas a diversos actores del ecosistema de eventos musicales y los focus group desarrollados al segmento objetivo conformado por personas de 18 a 40 años, con acceso a internet de los niveles socio-económicos A, B, C. En efecto, se encontró información relevante para poder entender las características del contexto limeño y las principales barreras a superar dentro del proceso, con lo que este proyecto profesional termina con una propuesta de plan de negocio aproximativa que permite mirar más de cerca la posibilidad de implementar en la ciudad de Lima una plataforma de crowdfunding para eventos musicales, consolidándose como una herramienta estratégica, útil y rentable para el núcleo creativo, combinando los eventos musicales, estrategias de gestión y la tecnología. Este proyecto profesional busca generar valor social como económico y que el modelo de negocio de crowdfunding que ya recauda millones de dólares a lo largo del mundo, pueda iniciarse de manera sólida en la ciudad de Lima y posteriormente, en todo el territorio peruano.Tesi

Mechanisms of coronavirus pathogenicity and virus-host interactions

Trabajo presentado en la Conference on the Cooperation and Collaboration on Prevention and Control of Animal Diseases, celebrada en Hangzhou (China), del 21 al 23 de mayo de 2019Coronaviruses (CoVs) are important human and animal pathogens mainly causing respiratory and enteric infections with diverse severity. The presence of CoVs in bats, as animal reservoirs, and their ability for interspecies transmission have recently led to the emergence of novel CoVs responsible for epidemics in humans and livestock. In order to develop protection strategies against CoV infections, our laboratory is interested in the identification of (i) Viral factors involved in virulence and (ii) Host signaling pathways contributing to pathogenesis, using human coronaviruses SARS- and MERS-CoVs as model systems

Un estudio sobre el potencial del uso de residuos lignocelulósicos

En este trabajo, se presentan diversos estudios relacionados con el aprovechamiento de residuos lignocelulósicos para diversas aplicaciones, como la obtención de azúcares, combustibles, alcoholes, plásticos, entre otros. Además, se muestran diversos métodos para combatir la recalcitrancia generada por la lignina en los residuos lignocelulósicos, y las diferentes técnicas para el aprovechamiento de estos residuos

Explanatory Factors for Periprosthetic Infection in Total Knee Arthroplasty

There are many studies whose results reveal possible risk factors for developing an infection after a total knee arthroplasty (TKA). The objective of this study is to analyse the risk factors that depend on the hospital and, especially, if the patellar replacement influences the appearance of periprosthetic infection. A retrospective study was performed, where data from the electronic registry of patients of people over 18 and who had undergone TKA, between the years 2015 and 2018, were reviewed. Dependent variables on the patients and the health care system were collected. The possible associations between the factors and the appearance of infection after TKA were studied using univariate and multivariate regression analyses. A total of 907 primary knee arthroplasties were included in the study. Those patients who had their patella replaced had a significantly higher risk of developing an infection (OR 2.07; 95% confidence interval 1.01–6.31). Likewise, patients who underwent surgery by surgeons with more than 10 years of experience were more than twice as likely to become infected than those operated on by younger surgeons (OR 2.64; 95%CI 1.01–6.97). Male patients were also found to be three times more likely to be infected than women (OR 2.99; 95%CI 1.32–5.74). Those interventions that were longer had a higher risk of infection. The same happened with patients who stayed in the hospital for a longer period of time. The rest of the variables did not show statistically significant results. In this study, it was found that the replacement of the patella may be a factor of infection, but it should be corroborated with randomized clinical trials. Furthermore, patients who underwent longer surgeries or those with prolonged hospital stays should be closely monitored to detect infection as soon as possible and establish the most appropriate treatment

Nature-based strategies to regenerate the functioning and biodiversity of vineyards

16 páginas.- 2 figuras.- 1 Box.- 138 referenciasGrapevine is one of the most important perennial fruit crops worldwide. Historically, vineyards were compatible with soil conservation practices and multitrophic biodiversity, but vineyards are now generally eroded and biologically impoverished, making them more susceptible to pests and diseases. However, the idiosyncrasy of the wine sector places wine growers in a unique position to lead the adoption of a range of sustainable management strategies and, thus, to pioneer a wider transformation of the agricultural sector. In this article, we provide an overview of nature-based management strategies that may be used for the regeneration of the functioning and biodiversity of vineyards and that may also lead to improved plant nutrition, grape berry quality and the suppression of pathogens and pests. These strategies include the use of microbial and nonmicrobial biostimulants, fertilization with organic amendments as well as foliar fertilization with nature-based products, the use of cover crops and the reintegration of livestock in vineyards, especially sheep. We will also pay special attention to the implementation of circular economy in the vineyard in relation to the previously mentioned management strategies and will also discuss the importance of considering all these aspects from a holistic and integrative perspective, rather than taking them into account as single factors. Assuming the integral role of soils in the functioning of agroecosystems, soils will be considered transversally across all sections. Finally, we will argue that the time is now ripe for innovation from the public and private sectors to contribute to the sustainable management of vineyards while maintaining, or even improving, the profit margin for farmers and winemakers.This review article is, in part, the result of a workshop (I Jornadas ‘Suelos Vivos’ para la regeneración de la vida en suelos de viñedos gaditanos; https://suelosvivos.es/i-jornadas-suelos-vivos/) carried out within the context of the ‘Suelos Vivos’ Regional Operational Group of the EIP-Agri, which was celebrated between 23 and 24 March 2023 in Puerto Real, Cádiz. Raúl Ochoa-Hueso was supported by the Ramón y Cajal programme from the MICINN (RYC-2017 22032), by the Spanish Ministry of Science and Innovation for the I + D + i project PID2019-106004RA-I00 funded by MCIN/AEI/10.13039/501100011033, by the Fondo Europeo de Desarrollo Regional (FEDER) y la Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático ‘01 - Refuerzo de la investigación, el desarrollo tecnológico y la innovación’): P20_00323 (FUTUREVINES), and by the Fondo Europeo Agrícola de Desarrollo Rural (FEADER) through the ‘Ayudas a Grupos operativos de la Asociación Europea de Innovación (AEI) en materia de productividad y sostenibilidad agrícolas’, Referencia: GOPC-CA-20-0001. Manuel Delgado-Baquerizo acknowledges support from TED2021-130908B-C41/AEI/10.13039/501100011033/Unión Europea NextGenerationEU/PRTR and from the Spanish Ministry of Science and Innovation for the I + D + i project PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033. Cristina Lazcano acknowledges support from the California Department of Food and Agriculture (21-0433-021-SF) and the Foundation for Food and Agriculture Research (FFAR, CA21-SS-0000000193). Lilia Serrano-Grijalva thanks the European Union's Horizon 2020 research and innovation programme who funded her work under the Marie Skłodowska-Curie Grant Agreement No. 890874Peer reviewe

EDUCACIÓN AMBIENTAL Y SOCIEDAD. SABERES LOCALES PARA EL DESARROLLO Y LA SUSTENTABILIDAD

Este texto contribuye al análisis científico de varias áreas del conocimiento como la filosofía social, la patología, la educación para el cuidado del medio ambiente y la sustentabilidad que inciden en diversas unidades de aprendizaje de la Licenciatura en Educación para la Salud y de la Maestría en Sociología de la SaludLas comunidades indígenas de la sierra norte de Oaxaca México, habitan un territorio extenso de biodiversidad. Sin que sea una área protegida y sustentable, la propia naturaleza de la región ofrece a sus visitantes la riqueza de la vegetación caracterizada por sus especies endémicas que componen un paisaje de suma belleza