Massive migration from the steppe is a source for Indo-European languages in Europe

We generated genome-wide data from 69 Europeans who lived between 8,000-3,000 years ago by enriching ancient DNA libraries for a target set of almost four hundred thousand polymorphisms. Enrichment of these positions decreases the sequencing required for genome-wide ancient DNA analysis by a median of around 250-fold, allowing us to study an order of magnitude more individuals than previous studies and to obtain new insights about the past. We show that the populations of western and far eastern Europe followed opposite trajectories between 8,000-5,000 years ago. At the beginning of the Neolithic period in Europe, ~8,000-7,000 years ago, closely related groups of early farmers appeared in Germany, Hungary, and Spain, different from indigenous hunter-gatherers, whereas Russia was inhabited by a distinctive population of hunter-gatherers with high affinity to a ~24,000 year old Siberian6 . By ~6,000-5,000 years ago, a resurgence of hunter-gatherer ancestry had occurred throughout much of Europe, but in Russia, the Yamnaya steppe herders of this time were descended not only from the preceding eastern European hunter-gatherers, but from a population of Near Eastern ancestry. Western and Eastern Europe came into contact ~4,500 years ago, as the Late Neolithic Corded Ware people from Germany traced ~3/4 of their ancestry to the Yamnaya, documenting a massive migration into the heartland of Europe from its eastern periphery. This steppe ancestry persisted in all sampled central Europeans until at least ~3,000 years ago, and is ubiquitous in present-day Europeans. These results provide support for the theory of a steppe origin of at least some of the Indo-European languages of Europe

A graphical vector autoregressive modelling approach to the analysis of electronic diary data

<p>Abstract</p> <p>Background</p> <p>In recent years, electronic diaries are increasingly used in medical research and practice to investigate patients' processes and fluctuations in symptoms over time. To model dynamic dependence structures and feedback mechanisms between symptom-relevant variables, a multivariate time series method has to be applied.</p> <p>Methods</p> <p>We propose to analyse the temporal interrelationships among the variables by a structural modelling approach based on graphical vector autoregressive (VAR) models. We give a comprehensive description of the underlying concepts and explain how the dependence structure can be recovered from electronic diary data by a search over suitable constrained (graphical) VAR models.</p> <p>Results</p> <p>The graphical VAR approach is applied to the electronic diary data of 35 obese patients with and without binge eating disorder (BED). The dynamic relationships for the two subgroups between eating behaviour, depression, anxiety and eating control are visualized in two path diagrams. Results show that the two subgroups of obese patients with and without BED are distinguishable by the temporal patterns which influence their respective eating behaviours.</p> <p>Conclusion</p> <p>The use of the graphical VAR approach for the analysis of electronic diary data leads to a deeper insight into patient's dynamics and dependence structures. An increasing use of this modelling approach could lead to a better understanding of complex psychological and physiological mechanisms in different areas of medical care and research.</p

Lateral injection of oxygen with the Bosporus plume - fingers of oxidizing potential in the Black Sea

Saline and warm Mediterranean water flowing through the Bosporus Strait maintains a permanent pycnocline with vertical separation of oxic (O(2)), suboxic (absence of O(2) and H(2)S), and anoxic (H(2)S) zones in the Black Sea. The stable suboxic zone implies restricted vertical mixing of the upper oxic and lower anoxic layers and limited vertical flux of oxygen that cannot balance the upward flux of sulfide. We report data that directly confirm massive lateral injections (>200 km from the Bosporus) of oxygen-enriched waters of the Bosporus plume, created by the mixing of shallow, cold, intermediate-layer Black Sea water with Mediterranean water. These plume waters are laterally injected into the oxic layer and, more importantly, into the suboxic and anoxic layers over several small vertical scales ("fingers" of similar to5 m) at water densities (sigma(1)) from 15.0 to 16.4. O(2) injection oxidizes Mn(II) to Mn(III,IV), which then oxidizes H(2)S. The onset of H(2)S detection occurs in deeper waters in the southwest (>170 m; sigma(1) approximate to 16.4) relative to the west central Black Sea (110 m; sigma(1) approximate to 16.2) and coincides with increased MnO(2) and S(8) formation in the southwest

Mood Regulation and Cognitive Reactivity in Depression Vulnerability

There is substantial evidence supporting the hypothesis that cognitive reactivity is an important variable in the etiology of depression. However, there is a lack of studies examining possible mechanisms that underlie cognitive reactivity. The present study tested whether two specific mood regulation processes differentially appear in vulnerable and non-vulnerable individuals, and whether they can account for differences in cognitive reactivity. In a cross-sectional experimental design, 20 formerly-depressed individuals (FD) were compared with 20 never-depressed individuals (ND). In an autobiographical memory task both groups differed concerning the use of positively and negatively toned emotion words: FD retrieved fewer positive emotion words than ND in the second phase of this task. Furthermore, FD with a high cognitive reactivity retrieved more negatively toned emotion words. In the ND group there was a different pattern: Subjects with a high cognitive reactivity retrieved less positively toned emotion words. Two different cognitive processes seem to account for cognitive reactivity in individuals who are at high versus low risk for depression