Genomic landscape of the global oak phylogeny.

The tree of life is highly reticulate, with the history of population divergence emerging from populations of gene phylogenies that reflect histories of introgression, lineage sorting and divergence. In this study, we investigate global patterns of oak diversity and test the hypothesis that there are regions of the oak genome that are broadly informative about phylogeny. We utilize fossil data and restriction-site associated DNA sequencing (RAD-seq) for 632 individuals representing nearly 250 Quercus species to infer a time-calibrated phylogeny of the world's oaks. We use a reversible-jump Markov chain Monte Carlo method to reconstruct shifts in lineage diversification rates, accounting for among-clade sampling biases. We then map the > 20 000 RAD-seq loci back to an annotated oak genome and investigate genomic distribution of introgression and phylogenetic support across the phylogeny. Oak lineages have diversified among geographic regions, followed by ecological divergence within regions, in the Americas and Eurasia. Roughly 60% of oak diversity traces back to four clades that experienced increases in net diversification, probably in response to climatic transitions or ecological opportunity. The strong support for the phylogeny contrasts with high genomic heterogeneity in phylogenetic signal and introgression. Oaks are phylogenomic mosaics, and their diversity may in fact depend on the gene flow that shapes the oak genome.

High Tourniquet Failure Rates Among Non-Medical Personnel Do Not Improve with Tourniquet Training, Including Combat Stress Inoculation: A Randomized Controlled Trial.

BACKGROUND: The rate of failing to apply a tourniquet remains high. HYPOTHESIS: The study objective was to examine whether early advanced training under conditions that approximate combat conditions and provide stress inoculation improve competency, compared to the current educational program of non-medical personnel. METHODS: This was a randomized controlled trial. Male recruits of the armored corps were included in the study. During Combat Lifesaver training, recruits apply The Tourniquet 12 times. This educational program was used as the control group. The combat stress inoculation (CSI) group also included 12 tourniquet applications, albeit some of them in combat conditions such as low light and physical exertion. Three parameters defined success, and these parameters were measured by The Simulator: (1) applied pressure ≥ 200mmHg; (2) time to stop bleeding ≤ 60 seconds; and (3) placement up to 7.5cm above the amputation. RESULTS: Out of the participants, 138 were assigned to the control group and 167 were assigned to the CSI group. The overall failure rate was 80.33% (81.90% in the control group versus 79.00% in the CSI group; P value = .565; 95% confidence interval, 0.677 to 2.122). Differences in pressure, time to stop bleeding, or placement were not significant (95% confidence intervals, -17.283 to 23.404, -1.792 to 6.105, and 0.932 to 2.387, respectively). Tourniquet placement was incorrect in most of the applications (62.30%). CONCLUSIONS: This study found high rates of failure in tourniquet application immediately after successful completion of tourniquet training. These rates did not improve with tourniquet training, including CSI. The results may indicate that better tourniquet training methods should be pursued.Tsur, AM, Binyamin, Y, Koren, L, Ohayon, S, Thompson; P, Glassberg, E. High tourniquet failure rates among non-medical personnel do not improve with tourniquet training, including combat stress inoculation: a randomized controlled trial. Prehosp Disaster Med. 2019;34(3):282-287.

Comparative systematics and phylogeography of Quercus Section Cerris in western Eurasia: inferences from plastid and nuclear DNA variation.

Oaks (Quercus) comprise more than 400 species worldwide and centres of diversity for most sections lie in the Americas and East/Southeast Asia. The only exception is the Eurasian sect. Cerris that comprises about 15 species, most of which are confined to western Eurasia. This section has not been comprehensively studied using molecular tools. Here, we assess species diversity and provide a first comprehensive taxonomic and phylogeographic scheme of western Eurasian members of sect. Cerris using plastid (trnH-psbA) and nuclear (5S-IGS) DNA variation with a dense intra-specific and geographic sampling. Chloroplast haplotypes primarily reflected phylogeographic patterns originating from interspecific cytoplasmic gene flow within sect. Cerris and its sister section Ilex. We identified two widespread and ancestral haplotypes, and locally restricted derived variants. Signatures shared with Mediterranean species of sect. Ilex, but not with the East Asian Cerris oaks, suggest that the western Eurasian lineage came into contact with Ilex only after the first (early Oligocene) members of sect. Cerris in Northeast Asia had begun to radiate and move westwards. Nuclear 5S-IGS diversification patterns were more useful for establishing a molecular-taxonomic framework and to reveal hybridization and reticulation. Four main evolutionary lineages were identified. The first lineage is comprised of Q. libani, Q. trojana and Q. afares and appears to be closest to the root of sect. Cerris. These taxa are morphologically most similar to the East Asian species of Cerris, and to both Oligocene and Miocene fossils of East Asia and Miocene fossils of western Eurasia. The second lineage is mainly composed of the widespread Q. cerris and the narrow endemic species Q. castaneifolia, Q. look, and Q. euboica. The third lineage comprises three Near East species (Q. brantii, Q. ithaburensis and Q. macrolepis), well adapted to continental climates with cold winters. The forth lineage appears to be the most derived and comprises Q. suber and Q. crenata. Q. cerris and Q.  trojana displayed high levels of variation; Q. macrolepis and Q. euboica, previously treated as subspecies of Q. ithaburensis and Q. trojana, likely deserve independent species status. A trend towards inter-specific crosses was detected in several taxa; however, we found no clear evidence of a hybrid origin of Q. afares and Q. crenata, as currently assumed.