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Traditional approaches of quantifying population-level exposure to air pollution assume that concentrations of air pollutants at the residential address of the study population are representative for overall exposure. This introduces potential bias in the quantification of human health effects. Our study combines new UK Census data comprising information on workday population densities, with high spatio-temporal resolution air pollution concentration fields from the WRF-EMEP4UK atmospheric chemistry transport model, to derive more realistic estimates of population exposure to NO2, PM2.5 and O3. We explicitly allocated workday exposures for weekdays between 8:00 am and 6:00 pm. Our analyses covered all of the UK at 1 km spatial resolution. Taking workday location into account had the most pronounced impact on potential exposure to NO2, with an estimated 0.3 μg m−3 (equivalent to 2%) increase in population-weighted annual exposure to NO2 across the whole UK population. Population-weighted exposure to PM2.5 and O3 increased and decreased by 0.3%, respectively, reflecting the different atmospheric processes contributing to the spatio-temporal distributions of these pollutants. We also illustrate how our modelling approach can be utilised to quantify individual-level exposure variations due to modelled time-activity patterns for a number of virtual individuals living and working in different locations in three example cities. Changes in annual-mean estimates of NO2 exposure for these individuals were considerably higher than for the total UK population average when including their workday location. Conducting model-based evaluations as described here may contribute to improving representativeness in studies that use small, portable, automatic sensors to estimate personal exposure to air pollution.

Two preference tests were conducted with 16 lactating dairy cows in which they were allowed to choose between strawyard and cubicle housing systems. The two tests each of 14 days duration examined preferences at high and low space allowances. All cows had previous experience of both systems, but in the week prior to the preference tests, half the animals were housed in a strawyard and half in a cubicle system. This prior treatment was found to have no significant influence on subsequent choice of housing system. Continuous video recordings showed that the mean proportion of time over 14 days spent in the strawyard and cubicle areas was 66:34 at high space allowance and 68:32 at low space allowance respectively. In the second week of test at both space allowances, the total lying time proportion in the strawyard and cubicles was 91:09 indicating a strong preference to lie in the strawyard area, even when the area was restricted at the low space allowance. Social rank and dominance values were determined prior to the tests, and were found to correlate more strongly with age than with liveweight. They did not significantly influence the choice of housing system at either space allowance. The occurrence of minority preferences for the cubicle system suggests that using preference as an indicator of welfare, may lead to the development of systems which will not provide the best welfare for all animals.Dois testes de preferência foram conduzidos em 16 vacas leiteiras em lactação as quais tiveram que escolher entre confinamento com baias (com divisórias na área de repouso) ou sem baias (sem divisórias na área de repouso). Os dois testes, cada um com 14 dias de duração examinaram preferência dos animais em diferentes disponibilidades de espaço. Todas as vacas tinham experiência prévia nos dois tipos de confinamentos, mas, na semana anterior aos testes de preferência, metade dos animais foram mantidos no confinamento sem baias e a outra metade no confinamento com baias. Não foi observada influência desse tratamento prévio na escolha do tipo de confinamento pelos animais. O registro continuo, através de vídeo mostrou que, depois de 14 dias, a proporção mêdia de tempo despendido nas áreas dos confinamento sem e com baias foi respectivamente de 66:34 quando havia maior disponibilidade de espaço e de 68:32 quando havia menor disponibilidade de espaço. Na segunda semana dos dois testes verificou-se que, em ambas disponibilidade de espaço a proporção total de tempo em repouso no confinamento sem e com baias foi de 91:09, indicando uma forte preferência dos animais para se deitarem na área do confinamento sem baias, mesmo quando o espaço disponível para os mesmos foi restringido. Ordem social e valor de dominância foram determinados antes dos testes e verificou-se que correlacionavam mais fortemente com idade do que com peso vivo. Eles não tiveram influência significativa na escolha do sistema de confinamento pelos animais em ambas disponibilidades de espaço. A escolha do sistema de confinamento com baias pela minoria dos animais sugere que o fato de se usar testes de preferência como indicador de bem-estar pode levar ao desenvolvimento de sistemas que não fornecem o melhor bem-estar para todos os animais.

Se evaluó la dinámica degradativa de forrajes, en muestras de una pradera permanente (Lolium perenne L.), manejadas a dos alturas de pradera, alta y baja. Las muestras consistieron en forraje disponible a ras de suelo (FD) y en forraje aparentemente consumido por vacas lecheras en pastoreo continuo (FS). La degradabilidad ruminal se estudió usando la técnica de las bolsas de dacrón y los datos fueron ajustados a una ecuación exponencial. La fracción soluble (g/kg MS), de la materia seca (MS) (299 v/s 351, s.e.d.= 5,4), de la materia organica (MO) (304 v/s 376, s.e.d.= 3,3) y del nitrógeno (250 v/s 301, s.e.d.= 6,4), fueron significativamente mayores (P