On the uniqueness and global dynamics of AdS spacetimes

We study global aspects of complete, non-singular asymptotically locally AdS spacetimes solving the vacuum Einstein equations whose conformal infinity is an arbitrary globally stationary spacetime. It is proved that any such solution which is asymptotically stationary to the past and future is itself globally stationary. This gives certain rigidity or uniqueness results for exact AdS and related spacetimes.Comment: 18pp, significant revision of v

Management of domesticated boer goat (Capra hircus) and free ranging kudu (Tragelaphus strepsiceros) in a production system

International audienc

Environmental-genotype responses in livestock to global warming: A southern African perspective

Global warming will change Southern Africa’s environments from grass dominated vegetation to dry woodland and desert with a vegetation of C4 dominated grasses, whereas the grazing capacity is expected to decline by more than 30%. Animals will also be more exposed to parasites and diseases, mainly as a result of an increase in temperature. An improved understanding of the adaptation of livestock to their production environments is thus important, but the measurement of adaptation is complex and difficult. Proxy-indicators for adaptation, such as reproductive and production traits, can however be used. Adaptation can also be characterized indirectly by describing the production environment in which a breed or population has been kept over a period of time and to which it has become adapted. By describing production environments it will be possible to identify breeds or genotypes that may be adapted to the changed environment of an area. In respect of quantitative breeding technology, fixed and random effects that account for spatial and temporal variation in production environments will have to be identified and physiological breeding value estimations may be necessary. Tools will need to be developed to overlay geo-referenced data sets available onto the different production environments in order to quantify them. Gene or marker assisted selection may play an important role in selection for disease and parasite resistance or tolerance, since it is difficult to measure these traits directly. The development of a high-throughput SNP or gene chip (genomic selection based on Single Nucleotide Polymorphisms) may enhance the utilization of marker assisted selection. Recent research has indicated that the inclusion of information from DNA analysis into BLUP breeding values may result in substantial increases in genetic gain at reduced cost. Strategies that utilizes EBVs derived from genomic analyses (genomic EBVs), together with conventional mixed model methodology, may speed up the process of breeding animals that are adapted to the newly created environment as a result of global warming.Keywords: Global warming, livestock production, adaptation, animal breedin

Correlations between physical and chemical defences in plants: tradeoffs, syndromes, or just many different ways to skin a herbivorous cat?

� Most plant species have a range of traits that deter herbivores. However, understanding of how different defences are related to one another is surprisingly weak. Many authors argue that defence traits trade off against one another, while others argue that they form coordinated defence syndromes. � We collected a dataset of unprecedented taxonomic and geographic scope (261 species spanning 80 families, from 75 sites across the globe) to investigate relationships among four chemical and six physical defences. � Five of the 45 pairwise correlations between defence traits were significant and three of these were tradeoffs. The relationship between species’ overall chemical and physical defence levels was marginally nonsignificant (P = 0.08), and remained nonsignificant after accounting for phylogeny, growth form and abundance. Neither categorical principal component analysis (PCA) nor hierarchical cluster analysis supported the idea that species displayed defence syndromes. � Our results do not support arguments for tradeoffs or for coordinated defence syndromes. Rather, plants display a range of combinations of defence traits. We suggest this lack of consistent defence syndromes may be adaptive, resulting from selective pressure to deploy a different combination of defences to coexisting species

Teenage pregnancy and parenthood: the role of fathers

From the research available in America and Britain it would appear that the men who father children by teenage mothers tend to be a few years older than their teenage partners, although a minority may be significantly older. With regard to the factors associated with fatherhood there are striking similarities to the literature on teenage mothers. Like teenage mothers young fathers tend to be from low socio-economic backgrounds, experience lower educational attainment and fewer employment opportunities than their childless peers. Similarly they tend to experience greater psychological and emotional difficulties and may have a history of delinquent behaviour.These young fathers are involved in a variety of relationships with teenage mothers, few of which result in marriage and many of which result in the breakdown of cohabitation or the termination of the relationship. This pattern of increasing relationship breakdown over time is related to decreasing paternal contact with children in both America and Britain. Often conflictual relationships with teenage mothers or maternal grandparents and a lack of financial resources are cited by young fathers as barriers to their continued involvement and contact with their children. However, the mothers are much more likely to cite paternal disinterest as the reason for a lack of paternal involvement and there is some indication that mothers and fathers have different views on the level of practical involvement expected from fathers. While most of quantitative data on the subject provides a rather negative picture of paternal involvement, qualitative research highlights how many young fathers genuinely want to be involved with their children and would have more contact and input if they could.While much less is known about the support provided to young fathers in comparison with their female counterparts, there is some suggestion that the support and role expectations provided by the paternal grandmother may influence how involved young fathers are. There is also some indication that a sizeable minority of young men may receive no such support from their family and may also be treated with hostility or ignored by the maternal grandparents. Young fathers also report limited or no contact with midwives, health visitors and social workers