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    Effect of acute sodium bicarbonate and caffeine co-ingestion on repeated sprint performance in recreationally trained individuals: a randomized controlled trial

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    24 p.Introduction: The acute and isolated ingestion of sodium bicarbonate (NaHCO3) and caffeine (CAF) improves performance and delays fatigue in high-intensity tasks. However, it remains to be elucidated if the coingestion of both dietary supplements stimulates a summative ergogenic effect. This study aimed to examine the effect of the acute coingestion of NaHCO3 and CAF on repeated-sprint performance. Methods: Twenty-five trained participants (age: 23.3 [4.0] y; sex [female/male]: 12/13; body mass: 69.6 [12.5] kg) participated in a randomized, double-blind, placebo (PLA) -controlled, crossover study. Participants were assigned to 4 conditions: (1) NaHCO3 + CAF, (2) NaHCO3, (3) CAF, or (4) PLA. Thus, they ingested 0.3 g/kg of NaHCO3, 3 mg/kg of CAF, or PLA. Then, participants performed 4 Wingate tests (Wt), consisting of a 30-second all-out sprint against an individualized resisted load, interspersed by a 1.5-minute rest period between sprints. Results: Peak (Wpeak) and mean (Wmean) power output revealed a supplement and sprint interaction effect (P = .009 and P = .049, respectively). Compared with PLA, NaHCO3 + CAF and NaHCO3 increased Wpeak performance in Wt 3 (3%, P = .021) and Wt 4 (4.5%, P = .047), while NaHCO3 supplementation increased mean power performance in Wt 3 (4.2%, P = .001). In Wt 1, CAF increased Wpeak (3.2%, P = .054) and reduced time to Wpeak (-8.5%; P = .008). Plasma lactate showed a supplement plus sprint interaction (P < .001) when NaHCO3 was compared with CAF (13%, P = .031) and PLA (23%, P = .021). Conclusion: To summarize, although the isolated ingestion of CAF and NaHCO3 improved repeated-sprint performance, the coingestion of both supplements did not stimulate a synergic ergogenic effect

    Estructura económica y sincronización de los ciclos económicos: evidencia de los estados de México

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    Estudios recientes documentan que la creciente integración económica entre México y los Estados Unidos, originada por el Tratado de Libre Comercio de América del Norte (TLCAN), transformó heterogéneamente las estructuras económicas de los estados de México. Este estudio provee evidencia que lo anterior alteró la naturaleza y el grado de sincronización económica entre ellos. Además, ilustra que existe una relación positiva, y cada vez más significativa a partir de 1994, entre la sincronización económica y la sofisticación de las estructuras económicas de los estados [medida por el Índice de Complejidad Económica (ICE)]. Con mayor integración económica, los shocks se trasmiten más fácilmente entre las economías estatales con estructuras económicas similares, ya sea porque sus características las hagan sensibles a las mismas clases de shocks o porque se las transfieren unas a otras, al estar más vinculadas. Nuestros resultados complementan la comprensión de la evolución económica de los estados durante el periodo analizado.According to recent studies, the growing economic integration between Mexico and the United States, that resulted from the North American Free Trade Agreement (NAFTA), heterogeneously transformed the economic structure of Mexico’s states. This study provides evidence that this, in turn, altered the degree and nature of economic synchronization among them. Furthermore, it shows evidence of an increasingly significant positive relationship from 1994 on between economic synchronization and the level of sophistication of states’ economic structures [measured by the Economic Complexity Index (ECI)]. As economic integration increases, it becomes easier for shocks to be transmitted between state economies with similar economic structures, either because their characteristics make them more sensitive to the same kinds of shocks or simply because they are so closely linked. Our results help provide a greater understanding of the states’ economic evolution during the period analyzed

    Titanium-catalyzed synthesis of polymyrcene and polyanethol and application as sustainable additives for poly(lactic acid)

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    The replacement of fossil-derived plastics with those obtained from bio-based resources, which present suitable performance to be employed as commodity plastics is currently an important field of research, given the urgent need to transition from a fossil-based to a more sustainable economy. In this context, this work is focused on the application of a catalytic system based on silsesquioxane-cyclopentadienyl titanium complexes for the preparation of bio-based polymers, which can be used as additives to improve the poor material properties of a biodegradable polymer such as poly(lactic acid) (PLA). These titanium complexes, when activated with methylaluminoxane or with triflate salts, are shown to be capable of the polymerization of two bio-based monomers: myrcene and anethole. It is notable that polymerizations with these two distinct monomers take place through different mechanisms. The resulting polymyrcene (PMy) and polyanethol (PAN) have been applied as modifiers for PLA. Binary blends of PMy and PLA exhibited a considerable decrease in Tg and the promotion of PLA crystallization for a PMy content below 15 wt%. The mechanical properties of the PLA/PMy blends also displayed plasticization, with a decrease in the elastic modulus and enhanced plasticity, which resulted in less fragile systems compared to pure PLA. Morphological analysis has indicated a partially miscible, phase-separated system with micron-sized domains. In contrast, PAN completely inhibited PLA crystallization and the PLA/PAN blends were immiscible, but well-dispersed, a phase-separated system was obtained in solvent-casting film preparation with very small PAN domains. The blends showed higher tensile modulus than pure PLA and an absence of plastic behaviour, resulting in more fragile systems upon the addition of PAN to PLA

    Growth in small cities: the case of Aragon (Spain)

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    In this paper, we analyse the effects of productive specialisation and diversity on population growth at the local level in Aragon, a NUTS 2 region in Spain. This region is characterised by a highly uneven population distribution, with numerous small cities, and a large proportion of small businesses. We estimate panel data models considering data from 2000 to 2015 at the local level, encompassing 577 municipalities. Our results show that both localisation and urbanisation have a statistically significant positive effect on growth in Aragonese municipalities but only in cities with a population threshold of 3,000 or more inhabitants.En este trabajo analizamos los efectos de la especialización y diversidad productiva en el crecimiento de la población a nivel local en Aragón, una región NUTS 2 de España. Esta región se caracteriza por una distribución de la población altamente desigual, con numerosas ciudades pequeñas, y una elevada proporción de empresas pequeñas. Estimamos modelos de datos panel considerando datos desde el año 2000 al 2015 a nivel local que abarcan 577 municipios. Nuestros resultados muestran que tanto la especialización como la diversidad tienen un efecto positivo estadísticamente significativo en el crecimiento de los municipios aragoneses, pero solo en aquellas ciudades con una población superior a los 3.000 habitantes

    Cómo abordar la pragmática en segundas lenguas en personas con Trastorno del Espectro Autista (TEA)

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    El Trastorno del Espectro Autista (TEA) es una condición neurológica y del desarrollo que afecta a la interacción social, la comunicación y el comportamiento de una persona. Se caracteriza por patrones de comportamiento repetitivos, dificultades en la comunicación verbal y no verbal, así como obstáculos a la hora de comprender las normas sociales implícitas para interactuar con otros hablantes. Esto supone complicaciones en su competencia pragmática por la falta de comprensión de los enunciados implícitos, las inferencias, la interpretación de segundas intenciones o la comprensión de la ironía, los dobles sentidos o el sarcasmo. Estos problemas se deben, en parte, a la deficiencia en el desarrollo de la Teoría de la Mente, ya que presentan déficits en la comprensión de creencias, intenciones y emociones tanto propias como ajenas. Consecuentemente, el estudio de la pragmática en L2/ LE en estudiantes con TEA es clave para comprender mejor las dificultades que enfrenta este perfil de estudiantes en los contextos comunicativos. La presente obra expone aquellas dificultades comunicativas relacionadas con la competencia pragmática en estudiantes con TEA y propone herramientas para que la enseñanza a este grupo cubra sus necesidades y déficits lingüísticos y mejore su desarrollo comunicativo

    Scientists' warning to humanity for long-term planetary thinking on biodiversity and humankind preservation, a cosmic perspective

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    We are all made of stars,? the song claims. Indeed, as Carl Sagan said, we are made of star stuff. But we often forget the message of unity ingrained in such reality. The typical narrow short-term perspective characterizing human planning, combined with self-interest, frequently leads to a tragedy of the commons where the very same resources essential for survival or prosperity are compromised or destroyed (Hardin 1968). Such selfish exploitation of common goods sits at the base of many current global problems, including the depletion of natural resources, accelerated climate change, and the loss of biodiversity. Fortunately, there is an increasing awareness of the importance of the natural environment, and an emerging paradigm shift is attempting to ameliorate the negative consequences of global problems for our children and subsequent generations. However, most if not all current plans are somehow shortsighted. For example, the Sustainable Development Goals adopted by the United Nations in 2015 set their targets for the year 2030. The United Nations Climate Change Conferences of the Parties implicitly or explicitly set their purposes for one or a few generations. The question is whether short-term goals and vision will be enough?or even adequate?to ensure the preservation of most life forms, including humanity, into the distant future. Although short-term targets are essential to trigger the necessary immediate action, shouldn&apos;t biodiversity preservation thinking and planning occur on a much longer time frame? If so, what is the appropriate time frame

    The contribution of acorn and soil N to early development of Chinese cork oak (Quercus variabilis Blume) seedlings under contrasting soil fertility conditions

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    40 p.Several studies have addressed the role of soil fertility on acorn N remobilization during seedling growth, but have focused on very early development stages or have assessed remobilization at a coarse grain ontogenetic scale making it difficult to know the precise time when seedlings switch from acorn N to soil N use. We cultivated Quercus variabilis seedlings under two distinct soil N fertility and assessed their growth, acorn N remobilization, and absorption of soil N at five distinct development stages, spanning from the incipient shoot emergence to the completion of the second flush of growth. Acorn N contributed more to seedling N content than soil N at all development stages. Seedlings began to uptake substantial amounts of soil N after the completion of leaf expansion during the first shoot flush of growth, coinciding with a fine root area that reached 50% of the maximum value observed at the end of the study. Roots became less dependent on acorn N before shoots. Soil fertility, rather than seedling growth rate, determined soil N uptake after the completion of leaf expansion in the first shoot flush of growth. We conclude that the acorn is the primary N source for Q. variabilis seedlings until the completion of the first shoot flush of growth. Soil fertility does not significantly affect either the amount of N remobilized from acorns or the switch from acorn N to massive soil N use, suggesting a minimal effect of forest microhabitat fertility on acorn N utilization by Q. variabilis seedlings.Gobierno de EspañaComunidad de MadridNational Natural Science Foundation of ChinaChina Scholarship Counci

    Technological transformation in HRM through knowledge and training: Innovative business decision making

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    Human resource management (HRM) is a crucial aspect of the global economy, and there is a wealth of literature available on various aspects of managing human resources. There is a need to take these concepts and turn them into practical applications, and organizations and academic institutions have a vital role to play. By providing training and digital tools to enhance innovation and decision making, these entities can prepare the next generation of human resources and business leaders for the challenges they may face. This is especially relevant in light of the economic impact of pandemics and other unpredictable global events, which can have long-lasting effects on the economy. To address these challenges, a study was conducted to explore the potential use of business game simulators (BGS) as a solution. The results of the study are promising, showing that BGS can enhance pandemic preparedness, increase competitiveness, and provide a more comprehensive organizational viewpoint. To explore this hypothesis, the study used specific constructs, which were subjected to empirical processing and analysis. The results indicate that simulating past pandemics through BGS can help HRM and businesses be better prepared for future crises, and the BGS learning approach can offer a more realistic, global perspective for organization

    Subsidios a la vivienda para los hogares de renta baja: un panorama

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    Este trabajo pasa revista a una variedad de cuestiones asociadas al diseño de los subsidios a la vivienda dirigidos a los hogares de renta baja. Se discuten los programas basados en la oferta (i.e., vivienda pública y vivienda construida o rehabilitada por el sector privado con ayudas públicas) y los orientados a la demanda (i.e., vales de alquiler y certificados de alquiler), así como la evidencia empírica sobre sus efectos.In this paper we review a variety of issues related to the design of low-income housing subsidies. We discuss project-based assistance (i.e., public housing and privately-owned subsidized projects) and tenant-based assistance (i.e., rent vouchers and rent certificates), as well as the empirical evidence concerning their effects

    Challenged global economics amid conflict in warring countries

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    This research delves into the multifaceted challenges posed to society and regional development in the wake of Russia"s invasion of Ukraine, with a specific focus on the period spanning from February 2022 to February 2023 as a response to the social and entrepreneurial threats that have appeared due to the conflict. In addition, this research seeks not only to alleviate prevailing uncertainties but also to facilitate a comprehensive understanding of the economic landscape by identifying causal factors and providing a relevant contextual framework for the threats to society and regional development in the aftermath of Russia"s invasion of Ukraine, which affects sustainability both economically and socially. These disruptions have given rise to unprecedented uncertainties that could potentially trigger an irreversible cascade of shortages, leading to escalating costs of critical or irreplaceable products that directly affect regional development. This paper scrutinizes this intricate process, aiming to discern underlying patterns and mitigate the prevailing uncertainty&#8212;a state that challenges rational decisionmaking. In this pursuit, established economic theories are deployed to provide comprehensive insights into the evolving reality. Through an in-depth analysis of the interplay between the Covid-19 pandemic, the ensuing economic crisis, and the ramifications of the Ukraine-Russia conflict, this research reveals a stark decline in economic growth. In addition, the present study explores potential solutions, emphasizing the importance of enhancing workforce skills through meticulously designed educational strategies and promoting gender diversity in science, technology, engineering and mathematics (STEM) programs

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