Aplicación del motor de inducción lineal como unidad motriz en un tren subterráneo de diseño convencional

Este trabajo describe una investigación realizada para determinar una posible aplicación del motor de inducción lineal en trenes subterráneos de diseño convencional. El estudio se realiza en base a una configuración especial propuesta, que consiste en un cierto número de primarios colocados sobre la vía y entre los rieles; los primarios se van conectando a una red de frecuencia normal a medida que el tren avanza v son alcanzados por el secundario que va ubicado bajo los coches. A partir de una curva fuerza-distancia v suponiendo un modelo ideal para el motor de inducción lineal, se establecen las ecuaciones necesarias para determinar la curva velocidad-distancia. Se desarrolla un método para determinar el consumo anticipado de energía. Se incluyen resultados numéricos de un ejemplo específico

Influences of thermal environment on fish growth

Indexación: Scopus.Thermoregulation in ectothermic animals is influenced by the ability to effectively respond to thermal variations. While it is known that ectotherms are affected by thermal changes, it remains unknown whether physiological and/or metabolic traits are impacted by modifications to the thermal environment. Our research provides key evidence that fish ectotherms are highly influenced by thermal variability during development, which leads to important modifications at several metabolic levels (e.g., growth trajectories, microstructural alterations, muscle injuries, and molecular mechanisms). In Atlantic salmon (Salmo salar), a wide thermal range (ΔT 6.4°C) during development (posthatch larvae to juveniles) was associated with increases in key thermal performance measures for survival and growth trajectory. Other metabolic traits were also significantly influenced, such as size, muscle cellularity, and molecular growth regulators possibly affected by adaptive processes. In contrast, a restricted thermal range (ΔT 1.4°C) was detrimental to growth, survival, and cellular microstructure as muscle growth could not keep pace with increased metabolic demands. These findings provide a possible basic explanation for the effects of thermal environment during growth. In conclusion, our results highlight the key role of thermal range amplitude on survival and on interactions with major metabolism-regulating processes that have positive adaptive effects for organisms.http://onlinelibrary.wiley.com/doi/10.1002/ece3.3239/ful

Neoseiulus californicus (Acari: Phytoseiidae, McGregor): o ácaro predador dominante em pomares comerciais de macieira conduzidos nos Sistema Convencional e Produção Integrada.

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Methane production from mixed tropical savanna and forest vegetation in Venezuela

International audienceMeasurements of methane concentrations in the boundary layer in the northern part of the Guayana shield, Venezuela, during the wet season (October 1988), showed the presence of substantial methane surface emissions. The measuring site is within the savanna climate region, but is affected by emissions from savanna and forest vegetation. From day versus night concentration measurements, with higher concentrations during night, a methane source strength near the site of 3?7×1011 molecules/cm2/s can be estimated, which includes emissions from small tracts of flooded soils, termites and especially tropical vegetation. Extrapolated to the entire savanna, this may imply a methane source of ~30?60 Tg yr?1 similar to the one calculated for tropical vegetation on the basis of recently published in vitro plant emission experiments by Keppler et al. (2006), which indicate emissions of ~30 Tg yr?1 for tropical savannas and grasslands and ~78 Tg yr?1 for tropical forests

Cultural animation in health research: An innovative methodology for patient and public involvement and engagement

Background A significant challenge in Patient and Public Involvement and Engagement (PPIE) in health research is to include a wide range of opinions and experiences, including from those who repeatedly find themselves at the margins of society. Objective To contribute to the debate around PPIE by introducing a bottom‐up methodology: cultural animation (CA). Cultural Animation is an arts‐based methodology of knowledge co‐production and community engagement which employs a variety of creative and participatory exercises to help build trusting relationships between diverse participants (expert and non‐experts) and democratize the process of research. Design Three CA full‐day workshops for the research project “A Picture of Health.” Participants Each workshop was attended by 20‐25 participants including 4 academics, 5 retired health professionals who volunteered in the local community and 15 community members. Participants ranged in age from 25 to 75 years, and 80% of the participants were women over the age of 60. Results The CA workshops unearthed a diversity of hidden assets, increased human connectivity, led to rethinking of and co‐creating new health indicators and enabled participants to think of community health in a positive way and to consider what can be developed. Discussion Cultural animation encourages participants to imagine and create ideal pictures of health by experimenting with new ways of working together. Conclusion We conclude by highlighting the main advantages to PPIE as follows: CA provides a route to co‐produce research agendas, empowers the public to engage actively with health professionals and make a positive contribution to their community

Universal arrays

A word on $q$ symbols is a sequence of letters from a fixed alphabet of size $q$. For an integer $k\ge 1$, we say that a word $w$ is $k$-universal if, given an arbitrary word of length $k$, one can obtain it by removing entries from $w$. It is easily seen that the minimum length of a $k$-universal word on $q$ symbols is exactly $qk$. We prove that almost every word of size $(1+o(1))c_qk$ is $k$-universal with high probability, where $c_q$ is an explicit constant whose value is roughly $q\log q$. Moreover, we show that the $k$-universality property for uniformly chosen words exhibits a sharp threshold. Finally, by extending techniques of Alon [Geometric and Functional Analysis 27 (2017), no. 1, 1--32], we give asymptotically tight bounds for every higher dimensional analogue of this problem.Comment: 12 page

Porcine reproductive and respiratory syndrome prevalence and processing fluids use for diagnosis in United States breeding herds

Processing fluids have been recently adopted by the U.S. swine industry as a breeding herd PRRS monitoring tool due to their increased representativeness of animals within the herd. Here, we use the Morrison Swine Health Monitoring Project (MSHMP) database, representative of ~50% of the U.S. swine breeding herd, to describe processing fluids submissions for PRRS diagnosis and their relation to PRRS prevalence and time to stability over time between 2009 and 2020.info:eu-repo/semantics/publishedVersio

Cross talk between adipose tissue and placenta in obese and gestational diabetes mellitus pregnancies via exosomes

Obesity is an important public health issue worldwide, where it is commonly associated with the development of metabolic disorders, especially insulin resistance (IR). Maternal obesity is associated with an increased risk of pregnancy complications, especially gestational diabetes mellitus (GDM). Metabolism is a vital process for energy production and the maintenance of essential cellular functions. Excess energy storage is predominantly regulated by the adipose tissue. Primarily made up of adipocytes, adipose tissue acts as the body’s major energy reservoir. The role of adipose tissue, however, is not restricted to a “bag of fat.” The adipose tissue is an endocrine organ, secreting various adipokines, enzymes, growth factors, and hormones that take part in glucose and lipid metabolism. In obesity, the greater portion of the adipose tissue comprises fat, and there is increased pro-inflammatory cytokine secretion, macrophage infiltration, and reduced insulin sensitivity. Obesity contributes to systemic IR and its associated metabolic complications. Similar to adipose tissue, the placenta is also an endocrine organ. During pregnancy, the placenta secretes various molecules to maintain pregnancy physiology. In addition, the placenta plays an important role in metabolism and exchange of nutrients between mother and fetus. Inflammation at the placenta may contribute to the severity of maternal IR and her likelihood of developing GDM and may also mediate the adverse consequences of obesity and GDM on the fetus. Interestingly, studies on maternal insulin sensitivity and secretion of placental hormones have not shown a positive correlation between these phenomena. Recently, a great interest in the field of extracellular vesicles (EVs) has been observed in the literature. EVs are produced by a wide range of cells and are present in all biological fluids. EVs are involved in cell-to-cell communication. Recent evidence points to an association between adipose tissue-derived EVs and metabolic syndrome in obesity. In this review, we will discuss the changes in human placenta and adipose tissue in GDM and obesity and summarize the findings regarding the role of adipose tissue and placenta-derived EVs, with an emphasis on exosomes in obesity, and the contribution of obesity to the development of GDM

Biology of Stress and Physical Performance

Regular physical training leads to physical capacity and optimal sports performance, and although this relationship is usually linear, the athlete’s adaptation is conditioned by multiple factors: environmental, genetic and psychological. Studies have shown that between 70 and 85% of successful and unsuccessful athletes can be identified using psychological measures of personality and mood, a level higher than chance, but insufficient for the purpose of selecting athletes. The research indicates that the mood of the athletes exhibits a dose-response relationship with their adaptation to the training load; This finding has shown potential to reduce the incidence of overtraining syndrome in athletes who undergo rigorous physical training, through early detection using scales of perception of their mood and physiological measures such as the testosterone / cortisol index. Thus, the genetic and epigenetic modifications of the factors that regulate the hypothalamic-pituitary-adrenal axis and, therefore, the response to stress, have recently been associated with a detrimental effect on physical performance and early manifestations of the overtraining syndrome and the abandonment of training and competences

Leadership development and its effects on organizational performance

Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 87-92).The current environment demands a better quality of leadership in organizations. In order to improve leadership capabilities, companies can create leadership development programs. However, not all companies embrace leadership development programs. Those who do usually have several types of programs and treat these programs as part of their strategic plan to address challenges that companies are likely to face in the future. Reviewing the leadership research, I find there is a positive relationship between leadership development programs and organizational performance. Reviewing the leadership program research, I find that most leadership development programs were created in response to significant challenges organizations were facing. I present the MIT Sloan Fellows program, as an alternative program that some companies and individuals are choosing for leadership development. The program uses the Four Capabilities Model as a leadership theory, focusing on the tasks and capabilities needed of leaders. I administered two surveys to the Sloan Fellows Class 2011. Surveys results suggest some of the benefits the program provides to individuals and organizations. Among these findings, my evidence shows that a higher percentage of "leader companies" have leadership development programs, in contrast to "follower companies" that usually do not have leadership development programs.by Jose A. Sanhueza.S.M