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As técnicas conservacionistas são altamente relevantes para o uso sustentável do solo, especialmente em regiões do semiárido. O objetivo deste estudo foi investigar o impacto de técnicas conservacionistas na redução das perdas de sedimentos e no incremento da umidade do solo, utilizando parcelas sob chuva natural. O estudo foi realizado na Bacia do Rio Alto Ipanema, Brasil. O monitoramento experimental foi realizado em nove parcelas com diferentes condições de cobertura (solo descoberto; cobertura natural; cobertura morta; Palma Forrageira). A cobertura morta apresentou desempenho semelhante à cobertura vegetal arbórea natural, para controle de escoamento e perdas de sedimentos. A umidade do solo foi signifi cativamente maior nas parcelas com cobertura morta do que nas parcelas de solo descoberto. Adicionalmente, as linhas de Palma produziram resultados hidrológicos promissores. Experimentos complementares em laboratório, com chuvas simuladas, apresentaram resultados consistentes com as observações em campo, sob chuva natural.

Polymorphisms in the growth hormone (GH) and IGF type-1 (IGF1) genes have been associated with the economic traits in farm animals, including BW of some sheep breeds. However, it remains unknown if these polymorphisms also affect carcass traits in sheep. Thus, we aimed to identify polymorphisms in the GH and IGF1 genes in Santa Ines sheep in order to describe their allelic and genotypic frequencies as well as to test the hypotheses that they are associated with the carcass traits. Fragments of 4550 bp (IGF1) and 1194 bp (GH) were sequenced in up to 191 lambs. In all, 18 polymorphisms were identified in the IGF1 and 21 in the GH gene. The IGF1 polymorphisms rs430457475, rs412470350, rs409110739 and rs400113576 showed an additive effect on the internal carcass length (−0.9265±0.4223), rump girth (−2.9285±1.1473), rib yield (−1.0003±0.4588) and neck weight (−0.0567±0.0278), respectively. In addition, the polymorphisms rs58957314 in the GH affected the rib weight (−0.4380±0.1272) and rib yield (−2.2680±0.6970), loin weight (−0.1893±0.0516) and loin yield (−0.9423±0.3259), palette weight (−0.2265±0.0779) and palette yield (−0.9424±0.4184), leg weight (−0.3960±0.1375), neck weight (−0.0851±0.0394) and carcass finishing score (−0.1700±0.0839). These results allow us to conclude that there are polymorphisms in the IGF1 and GH genes associated with carcass traits in Santa Ines sheep, which can provide important information for marker-assisted selection.

Landfills and waste heaps require an engineered surface cover upon closure. The capping system can vary from a simple soil cover to multiple layers of earth and geosynthetic materials. Conventional design features a compacted soil layer, which suffers from drying out and cracking, as well as root and animal intrusion. Capillary barriers consisting of inclined fine-over-coarse soil layers are investigated as an alternative cover system. Under unsaturated conditions, the textural contrast delays vertical drainage by capillary forces. The moisture that builds up above the contact will flow downdip along the interface of the layers. Theoretical studies of capillary barriers have identified the hydraulic properties of the layers, the inclination angle, the length of the field and the infiltration rate as the fundamental characteristics of the system. However, it is unclear how these findings can lead to design criteria for capillary barriers. To assess the uncertainty involved in such approaches, experiments have been carried out in a 8 m long flume and on large scale test sites (40 m x 15 m). In addition, the ability of a numerical model to represent the relevant flow processes in capillary barriers has been examined.

Objective: To test the hypothesis that, controlling for socio-demographic factors, destructive behaviour among Aboriginal and non-Aboriginal female sole parents will not be significantly different., Method: This study took place among an urban population of sole parents in Adelaide, South Australia, living in government housing. Two sample subsets were made up of 52 Aboriginal and 45 non-Aboriginal mothers from similar postcodes. Trained interviewers administered a questionnaire which, in addition to basic demographic data, elicited information concerning finance, housing, upbringing, experience of abuse and police interaction. The major issue of concern in the study was suicide attempt., Results: 1-in-3 of the whole sample, 2-in-5 of the non-Aboriginal and 1-in-4 of the Aboriginal subset had attempted suicide at least once and half more than once. Statistical differences among 'attempters' vs. 'non-attempters', irrespective of ethnicity, included increased familial alcohol abuse, physical and sexual abuse, economic difficulty, poor self esteem and perceived discriminatory treatment by welfare agencies and, in the case of Aboriginals, by police., Conclusion: The social environment is critical to understanding destructive behaviour, including self-harm, regardless of culture or ethnicity. The data show that suicide attempts among female sole parents in State-housing is one of the few health indices for which Aboriginal statistics are less than for non-Aboriginals., Implications: It is evident that class, rather than ethnicity, better explains self-harm in this urban population. It is suggested that reluctance to access services, especially in times of crisis, relates in part to perceptions of care services and that, for Aboriginals, the value of culturally appropriate community-run services have specific public health and policy implications.