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• Key message: Variation among provenances of Acacia senegal (Senegalia senegal (L.) Britton) in their survival and growth in height and diameter at two sites in Senegal could be partly explained by the climate at their site of origin and also revealed genotype-by-environment interactions. Breeding programs and forest restoration projects should carefully select germplasm for optimal performance of this socioeconomically important tree species. • Context: Several studies have shown important differences in adaptive properties among provenances (origins) of African savanna tree species, but there is a lack of studies on how these differences are expressed in different environments and age and to what extent they reflect local adaptation. • Aims: This study investigates the survival and growth of trees from 15 African Acacia senegal (Senegalia senegal (L.) Britton) provenances tested in two environments and relates the differences among provenances to the climate at their site of origin and tree age. • Methods: The study is based on 14 years growth in a common garden trial at two sites (Bambey and Dahra, Senegal) that differ in water availability, followed up by later assessment after 23 years at one of the sites. • Results: The variation among provenances in survival, height, and diameter was significant, and differences could be partly explained by the climate at their site of origin. In general, provenances from dry sites survived better at both sites. However, we observed genotype-by-environmental interactions where provenances from dry sites on average performed relatively poorer in height and diameter at the wettest site (Bambey) compared to the drier site (Dahra), while the opposite was the case for provenances from wetter sites. • Conclusion: The results support that divergent selection creates and maintains local adaptation of Acacia senegal provenances in relation to growth (height and diameter) and survival in areas with different water availability. This has important implications for choice of appropriate planting material for tree planting and for conservation of genetic variation among natural populations, but also for prediction of the effects of climate change. [ABSTRACT FROM AUTHOR]

Context Peripheral populations especially those in the leading edge are isolated from rest of the areas in the species distribution range. This can make them less genetically diverse yet genetically distinct from the rest of the populations in the species distribution range. Evaluation of their genetic diversity is thus crucial in understanding the local adaptation potential of a species. Aims We investigated the genetic diversity and genotype by environment interaction at the northern parts of the distribution range of P. avium. Methods Quantitative genetic variation of growth, stem form, and spring phenology were assessed in progenies from 93 plus trees of P. avium selected from 43 locations at the north of the species distribution range in Sweden and tested at two Swedish sites and one Danish site. Results We find large quantitative genetic variation in growth and phenology at the northern part of the distribution range of P. avium. Only a limited genotype by environment interaction was observed with no clear indication of local adaptation at the northern parts of the species distribution. Conclusion We conclude that P. avium harbors a high level of genetic diversity at the north of its distribution range. Present patterns therefore reflect more likely the recent introduction of the species and dispersal dynamics rather than a long-term loss of diversity along South-North ecological clines during the Holocene. With no indications of genetic depletion in growth or phenology, the gene pool in the breeding program is considered suitable for the future propagation of the species in the tested area. [ABSTRACT FROM AUTHOR]

Case Presentation: A 49 year old man had ventricular fibrillation in his home, at room temperature, due to an ST-elevation myocardial infarction. He received Cardiac compression only resuscitation (CC-only) for 26 minutes by his wife, followed by four minutes of standard CPR by other lay persons until EMS-arrival. Gasping and moaning were observed during most of the CC-only period. The ambulance arrived at 30 minutes. The first ECG showed a fine ventricular fibrillation. Restoration of spontaneous circulation (ROSC) was achieved at 49 minutes after a total of four defibrillatory shocks. The patient recovered without any cerebral damage, and was discharged to his home after eight days hospitalization., Conclusions: This case demonstrates that early and powerful cardiac compressions alone without rescue breaths may maintain sufficient circulation and gas exchange to prevent neurological damage for more than 25 minutes. This should be kept in mind for Emergency Medical Dispatch Centrals giving Pre-arrival instructions to bystanders.