ABUELAS Y ABUELOS DEL S.XXI, CON NIÑAS Y NIÑOS DEL S. XXI. ¿QUÉ PODEMOS HACER?

Getting to grandparents is one of the vital experiences that will make us live a new stage in our lives. But it is also a situation that some people are not prepared and therefore do not take it with the same philosophy.Some people think to have grandchildren makes them "old" while others / think is a reborn, recover enthusiasm and energy.This essentially practical workshop brings to the undecided and also a little afraid or uncomfortable because it forces them to change the order of their lives, strategies to deal with their new stage with positivity.It first offered a theoretical information about the evolution of children and based on how they learn and guidelines to act.Giving importance to aspects of transmission of values, the complicity with the grandchildren and awareness about belonging to the "tribe" as an educational entity. Belonging to this tribe gives them the possibility of participating fully in society.This 'active ageing' means understand this stage of life as one cycle of personal growth, adding "life years and not years to life".Key words: ageing, tribe, complicity, ethical valuesResumen.Llegar a abuelos/as es una de las experiencias vitales que nos hará vivir una etapa nueva en nuestras vidas. Pero también es una situación para la que algunas personas no están preparadas y por lo tanto no se lo toman con la misma filosofía.El tener nietos/as algunos piensan que les convierte en “viejos” mientras que otros/as piensan que es un renacer, recuperan la ilusión y las energías.Este taller fundamentalmente práctico aporta a los indecisos y también un poco atemorizados o incómodos porque les obliga a cambiar el orden de sus vidas, estrategias para afrontar con positividad su nueva etapa.Les ofrece primero una información teórica sobre la evolución de los niños/as y basándonos en cómo aprenden, pautas para actuar.Dando suma importancia a los aspectos de transmisión de valores, la complicidad con los nietos/as y la toma de conciencia sobre la pertenencia a la “tribu” como ente educativo. La pertenencia a esta tribu les da la posibilidad de participar plenamente en la sociedad.Este “envejecimiento activo” implica entender esta etapa de la vida como un ciclo más de crecimiento personal, añadiendo “vida a los años y no años a la vida”.Palabras clave: envejecimiento, tribu, complicidad, valores.

Age-regulated expression of genetic and environmental variation in fitness traits. 2. Genetic effects and variances for viability among crosses from a factorial mating of six selected Leghorn strains

White Leghorn strains were crossed reciprocally in a complete factorial mating producing 6 pure strains and 30 strain-crosses, which were kept for two laying cycles: 133–496 d of age and 547–909 d. Hens were housed for lay individually in four two-tiered batteries of cages. Strain additive effects (Ai), strain sex-linked effects (Zi), strain-cross heterotic effects (hij) and residual effects were calculated using regression. Viability was high in the first cycle of egg production with only 1 to 3% mortality in each of the four 11-wk periods, but lower in the second cycle decreasing with age. There was significant variation among strains in additive autosomal and sex-linked genetic effects and strain-cross heterotic effects, which increased with age in the second cycle. Heterosis for viability was positive in some strain-crosses and negative in others with considerable changes with age. The magnitude of heterotic effects was generally greater than the magnitude of additive or sex-linked genetic effects for viability. These results imply that different genotypes mount subtly different genetic responses to the problems of viability with advancing age and that more than one theory of ageing could apply. The results are discussed in relation to the theoretical aspects of ageing genetics. Key words: Ageing, fitness, viability, genetic effects, genetic variation, environmental variation

Dynamics of the Ventilatory Response to Step Changes in End-Tidal PCO2 in Older Humans

The purpose of this study was to examine the ventilatory response to carbon dioxide (CO2) in young and older men. Six square-wave steps of end-tidal CO2 (PETCO2) were administered in euoxia (PETO2 = 100 torr), hyperoxia (PETO2 = 500 torr), and mild hypoxia (PETO2 = 60 torr) The peripheral and central chemoreflex loops were described by three parameters including a gain (gp and gc), time constant of the response(τp, τc), and a time delay (Tp, Tc), respectively. The young and older men showed similar characteristics for Tp and Tc, with Tp, being 3 to 5 s shorter than Tc. In hypoxia, the ventilatory responses of the old group were characterised by a significantly smaller gc and a smaller gp. In hypoxia, τc was significantly shortened from its euoxic value in the young group, but not in the old group. Thus, this study demonstrated that in older men, the ventilatory responses to CO2 in euoxia and hyperoxia are similar to younger men, while in hypoxia the ventilatory responses are characterised by smaller gain terms. Key words: ageing, hypercapnia, hypoxia, hyperoxia, control of breathing