72 research outputs found

    Mismeasure of secondary sexual traits: An example with horn growth in the Iberian ibex

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    Monitoring programmes and studies focused on secondary sexual characters (SSCs) depend on the accuracy of measurements. However, methods of measurements of SSC, such as horns of ungulates, vary throughout the literature. Thus, the accuracy of horn growth measurements as proxies of true horn growth and the comparability of results inferred from different horn growth measurements may be questionable. We used the horns of Iberian ibex Capra pyrenaica to compare horn growth measurements and to analyse reliability with true horn growth. Our results reveal that measurements used in previous studies differed substantially from true horn growth and volume estimated as a barrel appeared as the best proxy of annular segments of horns in the Iberian ibex. Horn growth measurements are not necessarily mutually comparable, just as classical measurements are not necessarily representative of true horn growth. We discuss the wider implications of these results and suggest that biological processes linked to horns of ungulates should be reappraised using improved and accurate measurements because horn growth pattern is a key factor in sustainable management and conservation plans of ungulate species around the world. © 2012 The Authors. Journal of Zoology © 2012 The Zoological Society of London.Peer Reviewe

    A global risk assessment of primates under climate and land use/cover scenarios

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    Primates are facing an impending extinction crisis, driven by extensive habitat loss, land use change, and hunting. Climate change is an additional threat, which alone or in combination with other drivers, may severely impact those taxa unable to track suitable environmental conditions. Here, we investigate the extent of climate and land use/cover (LUC) change‐related risks for primates. We employed an analytical approach to objectively select a subset of climate scenarios, for which we then calculated changes in climatic and LUC conditions for 2050 across primate ranges (N=426 species) under a best‐ and a worst‐case scenario. Generalised linear models were used to examine whether these changes varied according to region, conservation status, range extent, and dominant habitat. Finally, we reclassified primate ranges based on different magnitudes of maximum temperature change, and quantified the proportion of ranges overall and of primate hotspots in particular that are likely to be exposed to extreme temperature increases. We found that, under the worst‐case scenario, 74% of Neotropical forest‐dwelling primates are likely to be exposed to maximum temperature increases up to 7°C. In contrast, 38% of Malagasy savanna primates will experience less pronounced warming of up to 3.5°C. About one quarter of Asian and African primates will face up to 50% crop expansion within their range. Primary land (undisturbed habitat) is expected to disappear across species’ ranges, whereas secondary land (disturbed habitat) will increase by up to 98%. With 86% of primate ranges likely to be exposed to maximum temperature increases >3°C, primate hotspots in the Neotropics are expected to be particularly vulnerable. Our study highlights the fundamental exposure risk of a large percentage of primate ranges to predicted climate and LUC changes. Importantly, our findings underscore the urgency with which climate change mitigation measures need to be implemented to avert primate extinctions on an unprecedented scale

    La actividad física como herramienta para reducir el absentismo laboral debido a enfermedad en trabajadores sedentarios. Una revisión sistemática

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    Fundamentos: Se ha sugerido que los programas de actividad física (AF) podrían reducir el absentismo laboral por motivos de enfermedad en trabajadores sedentarios. Esta revisión tuvo como objetivo examinar la evidencia científica disponible para estudiar los efectos de la AF sobre el absentismo laboral teniendo en consideración el diseño del programa de AF. Métodos: Se realizó una búsqueda bibliográfica en 4 bases de datos (Medline, Sportdiscus, Web of Science y Embase) de ensayos clínicos y estudios observacionales publicados sobre AF y absentismo laboral, en inglés y en español, desde el inicio de indización hasta diciembre de 2017, utilizando la metodología PRISMA. Resultados: Un total de 10 estudios publicados cumplieron con los criterios de elegibilidad establecidos. Las evidencias encontradas en la revisión sugieren que la AF es efectiva como medida para reducir el absentismo laboral por motivos de enfermedad. En general, los estudios señalaron que se observan mayores probabilidades de ausentarse del trabajo en trabajadores sedentarios que en los físicamente activos. Conclusiones: La AF en general parece disminuir el absentismo laboral. En concreto, la AF vigorosa podría obtener mejores resultados que la realizada a intensidad moderada, aunque faltan estudios de intervención más rigurosos y específicos, con un mayor control sobre las variables de intervención. Background: Physical Activity (PA) programs have been suggested to lower absenteeism due to illness in sedentary employees. The aim of this review was to examine available scientific literature in order to study PA effects in workplace absenteeism taking the program design into consideration. Methods: A search through 4 databases (Medline, Sportdiscus, Web of Science and Embase), from inception to December 2017, was conducted to identify control intervention and observational studies about PA and absenteeism published in either English or Spanish language using PRISMA procedures. Results: A total of 10 published studies between 1981 and 2017 met the inclusion criteria. Evidence from the review suggested that PA is effective in reducing illness-related absence. Likelihood of being off from workplace reported with sedentary workers reach more probabilities when compared with exercisers. Conclusions: General PA is considered paramount in order to lower employees'' absenteeism, which could be more related to vigorous training. However, there is a lack of rigorous and more specific studies about the issue. More focused on PA effect on absenteeism, adjusted by intervention variables, research would be desirable

    Some Reflections on Age Discrimination, Referees’ Retirement Ages and European Sports (Law)

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    Introduction: This paper is the first in a series of reflections on the relationship between discrimination, sport and the law, a body of work that has been motivated in part by the potential impact of the 2000 Equalities Directive upon European sports law, but also by developments in human rights jurisprudence and in the domestic laws of several jurisdictions. The phenomenon of age discrimination in sport, and the social and economic impact thereof, has been far less widely considered than is the case with other forms of sports discrimination (although the literature would miraculously emerge if the subject-matter were more directly concerned with men’s professional football). In contrast, free movement and competition law have impacted significantly upon sports provisions that discriminate on the basis of nationality; it is equally evident that age discrimination in the context of sports employment has not been considered with anything approaching the degree of sophistication that pervades our understanding of discrimination in occupation or employment on the grounds of disability, sexual orientation and religion/belief (the other discriminatory forms that are covered by the 2000 Directive); and our poor understanding of age-related sports discrimination generally stands in marked contrast to our appreciation of how challenges to discrimination on the grounds of sex and race have precipitated far-reaching changes to sports practices. Throughout the EU, with the possible exception of the Irish Republic, age discrimination law is far less advanced than is the case with discrimination which takes any of those other forms, the remedies are weaker and fewer people are aware of them. However, this state of affairs will undoubtedly change under the impact of the Equalities Directive, and even though the provisions themselves (and member states’ transposing of them) attract legitimate criticism, some longstanding practices of sports bodies are now open to challenge

    Resonance locking in giant planets indicated by the rapid orbital expansion of Titan

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    Saturn is orbited by dozens of moons, and the intricate dynamics of this complex system provide clues about its formation and evolution. Tidal friction within Saturn causes its moons to migrate outwards, driving them into orbital resonances that pump their eccen- tricities or inclinations, which in turn leads to tidal heating of the moons. However, in gi- ant planets, the dissipative processes that determine the tidal migration timescale remain poorly understood. Standard theories suggest an orbital expansion rate inversely pro- portional to the power 11/2 in distance1, implying negligible migration for outer moons such as Saturn’s largest moon, Titan. Here, we use two independent measurements ob- tained with the Cassini spacecraft to measure Titan’s orbital expansion rate. We find Titan rapidly migrates away from Saturn on a timescale of roughly 10 Gyr, corresponding to a tidal quality factor of Saturn of Q ≃ 100, which is more than a hundred times smaller than most expectations. Our results for Titan and five other moons agree with the predic- tions of a resonance locking tidal theory2, sustained by excitation of inertial waves inside the planet. The associated tidal expansion is only weakly sensitive to orbital distance, motivating a revision of the evolutionary history of Saturn’s moon system. In particular, it suggests Titan formed significantly closer to Saturn and has migrated outward to its current position

    Higher levels of physical fitness are associated with a reduced risk of suffering sarcopenic obesity and better perceived health among elderly. The EXERNET multi-center study

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    Objective: To evaluate the associations between physical fitness levels, health related quality of life (HRQoL) and sarcopenic obesity (SO) and to analyze the usefulness of several physical fitness tests as a screening tool for detecting elderly people with an increased risk of suffering SO. Design: Cross-sectional analysis of a population-based sample. Setting: Non-institutionalized Spanish elderly participating in the EXERNET multi-centre study. Participants: 2747 elderly subjects aged 65 and older. Measurements: Body weight, height and body mass index were evaluated in each subject. Body composition was measured by bioelectrical impedance. Four SO groups were created based on percentage of body fat and relative muscle mass; 1) normal group, 2) sarcopenic group, 3) obesity group and 4) SO group. Physical fitness was evaluated using 8 tests (balance, lower and upper body strength, lower and upper body flexibility, agility, walking speed and aerobic capacity). Three tertiles were created for each test based on the calculated scores. HRQoL was assessed using the EuroQol visual analogue scale. Results: Participants with SO showed lower physical fitness levels compared with normal subjects. Better balance, agility, and aerobic capacity were associated to a lower risk of suffering SO in the fittest men (odds ratio < 0.30). In women, better balance, walking speed, and aerobic capacity were associated to a lower risk of suffering SO in the fittest women (odds ratio < 0.21) Superior perceived health was associated with better physical fitness performance. Conclusions: Higher levels of physical fitness were associated with a reduced risk of suffering SO and better perceived health among elderly. SO elderly people have lower physical functional levels than healthy counterparts

    La actividad física organizada en las personas mayores, una herramienta para mejorar la condición física en la senectud

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    Fundamentos. Un nivel adecuado de condición física (CF) es fundamental para el logro de un envejecimiento saludable. El objetivo de este estudio consistió en evaluar el impacto de la actividad física (AF) organizada y el número de horas de práctica sobre el nivel de CF de las personas mayores. Método. En el estudio participaron 3104 personas mayores de 65 años de España, pertenecientes al Proyecto Multicéntrico EXERNET (722 hombres y 2382 mujeres; edad media: 72, 1±5, 3 años). La CF se evaluó mediante 8 test específicos para esta población. La participación en AF organizada se registró mediante un cuestionario. Las diferencias en la CF en función de la práctica y número de horas de AF se midieron con ANCOVA ajustando por edad, horas de caminar y de estar sentado. Resultados. Aquellos que no participaban en este tipo de actividad incrementaban su riesgo de tener un nivel bajo de CF en la mayoría de las variables evaluadas, observándose algunas diferencias entre sexos (OR: desde 1, 6 hasta 2, 6 en hombres y desde 1, 4 hasta 2, 2 en mujeres). En los hombres no se observó ninguna diferencia significativa entre practicar menos de 2, 2-4 o más de 4 horas (todos P>0, 05), a excepción de la fuerza del brazo izquierdo; sin embargo, las mujeres que realizaban más de 2 horas de AF organizada a la semana tenían mayor equilibrio, fuerza de piernas y de brazos, flexibilidad de piernas, velocidad al caminar y resistencia aeróbica que aquellas que asistían a este tipo de sesiones menos de 2 horas a la semana (P<0, 05). Conclusiones. La práctica de AF organizada produce un efecto beneficioso sobre la CF de las personas mayores independientemente de la edad, las horas que estén sentados o el tiempo que dediquen a caminar. Background. An adequate level of fitness is critical to achieving healthy ageing. The aim of this study was to evaluate the impact of organized physical activity (PA) and the number of hours of practice on the fitness levels of the elderly. Method. A total of 3104 people over 65 years old from Spain, belonging to the EXERNET Multicenter Project (722 men and 2382 women, mean age: 72.1 +/- 5.3 years) participated in the study. Fitness was evaluated by 8 specific tests for this population. Participation in organized PA was recorded through a questionnaire. Differences in fitness values depending on the participation in PA and the number of hours were measured with ANCOVA adjusting for age, hours of walking and sitting time. Results. Those who did not participate in this type of activity increased their risk of having a low level of fitness in most variables evaluated, with some differences between sexes (OR: from 1.6 to 2.6 in men and from 1.4 to 2.2 in women). In men, no significant differences were observed between practicing less than 2, 2-4 or more than 4 hours (P>0, 05), with an exception in the strength of the left arm. However, women who performed more than 2 hours a week in organized PA had better balance, strength of lower and upper extremities, flexibility of lower extremities, walking speed and aerobic capacity than those who performed less than 2 hours of PA a week (P<0, 05). Conclusions. The practice of organized PA produces a beneficial effect on the fitness of the elderly regardless of age, hours of walking and time sitting per day

    Carbohydrate Metabolism Is Essential for the Colonization of Streptococcus thermophilus in the Digestive Tract of Gnotobiotic Rats

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    Streptococcus thermophilus is the archetype of lactose-adapted bacterium and so far, its sugar metabolism has been mainly investigated in vitro. The objective of this work was to study the impact of lactose and lactose permease on S. thermophilus physiology in the gastrointestinal tract (GIT) of gnotobiotic rats. We used rats mono-associated with LMD-9 strain and receiving 4.5% lactose. This model allowed the analysis of colonization curves of LMD-9, its metabolic profile, its production of lactate and its interaction with the colon epithelium. Lactose induced a rapid and high level of S. thermophilus in the GIT, where its activity led to 49 mM of intra-luminal L-lactate that was related to the induction of mono-carboxylic transporter mRNAs (SLC16A1 and SLC5A8) and p27Kip1 cell cycle arrest protein in epithelial cells. In the presence of a continuous lactose supply, S. thermophilus recruited proteins involved in glycolysis and induced the metabolism of alternative sugars as sucrose, galactose, and glycogen. Moreover, inactivation of the lactose transporter, LacS, delayed S. thermophilus colonization. Our results show i/that lactose constitutes a limiting factor for colonization of S. thermophilus, ii/that activation of enzymes involved in carbohydrate metabolism constitutes the metabolic signature of S. thermophilus in the GIT, iii/that the production of lactate settles the dialogue with colon epithelium. We propose a metabolic model of management of carbohydrate resources by S. thermophilus in the GIT. Our results are in accord with the rationale that nutritional allegation via consumption of yogurt alleviates the symptoms of lactose intolerance
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