Sequelae of early trauma from a neurobiological perspective

Childhood trauma is one of the most well-established risk factors for the development of mental disorders. Due to the availability of new technologies, we are now beginning to understand how early trauma gets under the skin and exerts a sustained influence on various domains of psychological functioning and health. In the present review we will first briefly summarize what is currently known about the neurobiological effects of childhood trauma. We will then consider genetic and epigenetic factors as possible mechanisms mediating the biological embedding of childhood trauma.Der Zusammenhang zwischen frühen Traumatisierungen in der Kindheit und einem erhöhten psychischen Erkrankungsrisiko ist in der Fachliteratur seit Langem gut belegt. Erst in den letzten Jahren beginnen wir aufgrund technologischer Fortschritte zu verstehen, wie frühe Traumatisierungen körperlich niedergeschrieben werden und sich so ein Leben lang auf verschiedene Aspekte unseres Verhaltens und Erlebens auswirken können. In der vorliegenden Übersicht wird zunächst der aktuelle Erkenntnisstand zu den neurobiologischen Auswirkungen von Kindheitstraumata kurz zusammengefasst. Danach werden genetische und epigenetische Faktoren als mögliche Mechanismen der biologischen Einbettung betrachtet

Prediction of slope instabilities due to deep-seated gravitational creep

International audienceDeep-seated gravitational creep in rock slopes, rock-flow or sackung is a special category of mass-movement, in which long-lasting small-scale movements prevail. The prime causes of these mass movements in the Alpine area seem to have been glacial retreat at ~15000 a B.P. Many sackung stabilize and some undergo the transition to rapid sliding. This paper concentrates on four mass-movements in crystalline complexes of the Austrian Alps which have been investigated for aspects of deep-seated gravitational creep and prediction of the transition to rapid sliding. The present-day extent of the creeping or sliding of the rock mass has been modelled by a process of progressive, stress induced damage. Subcritical crack growth has been assumed to control this process and also the velocity of the mass movement. A sliding surface and decreasing Coulomb stress at this surface as a function of slip is a precondition for instability. The development of the four examples has been modelled successfully by a rotational slider block model and the conception of subcritical crack growth and progressive smoothing of the sliding surface. The interrelations between velocity, pore water pressure, seismic activity and the state of the sliding surface have been derived. Finally we discuss how the hypothesis inherent in the models presented could be validated and used for prediction

Shot noise in ferromagnetic single electron tunneling devices

Frequency dependent current noise in ferromagnetic double junctions with Coulomb blockade is studied theoretically in the limit of sequential tunneling. Two different relaxation processes are found in the correlations between spin polarized tunneling currents; low frequency spin fluctuations and high frequency charge fluctuations. Spin accumulation in strongly asymmetric junctions is shown to lead to a negative differential resistance. We also show that large spin noise activated in the range of negative differential resistance gives rise to a significant enhancement of the current noise.Comment: 8 pages, 13 eps-figures include

Extrinsic Magnetotransport Phenomena in Ferromagnetic Oxides

This review is focused on extrinsic magnetotransport effects in ferromagnetic oxides. It consists of two parts; the second part is devoted to an overview of experimental data and theoretical models for extrinsic magnetotransport phenomena. Here a critical discussion of domain-wall scattering is given. Results on surfacial and interfacial magnetism in oxides are presented. Spin-polarized tunnelling in ferromagnetic junctions is reviewed and grain-boundary magnetoresistance is interpreted within a model of spin-polarized tunnelling through natural oxide barriers. The situation in ferromagnetic oxides is compared with data and models for conventional ferromagnets. The first part of the review summarizes basic material properties, especially data on the spin-polarization and evidence for half-metallicity. Furthermore, intrinsic conduction mechanisms are discussed. An outlook on the further development of oxide spin-electronics concludes this review.Comment: 133 pages, 47 figures, submitted to Rep. Prog. Phy

Identifying genetic differences between bipolar disorder and major depression through multiple GWAS.

Background; Accurate diagnosis of bipolar disorder (BD) is difficult in clinical practice, with an average delay between symptom onset and diagnosis of about 7 years. A key reason is that the first manic episode is often preceded by a depressive one, making it difficult to distinguish BD from unipolar major depressive disorder (MDD). Aims; Here, we use genome-wide association analyses (GWAS) to identify differential genetic factors and to develop predictors based on polygenic risk scores that may aid early differential diagnosis. Methods; Based on individual genotypes from case-control cohorts of BD and MDD shared through the Psychiatric Genomics Consortium, we compile case-case-control cohorts, applying a careful merging and quality control procedure. In a resulting cohort of 51,149 individuals (15,532 BD cases, 12,920 MDD cases and 22,697 controls), we perform a variety of GWAS and polygenic risk scores (PRS) analyses. Results; While our GWAS is not well-powered to identify genome-wide significant loci, we find significant SNP-heritability and demonstrate the ability of the resulting PRS to distinguish BD from MDD, including BD cases with depressive onset. We replicate our PRS findings, but not signals of individual loci in an independent Danish cohort (iPSYCH 2015 case-cohort study, N=25,966). We observe strong genetic correlation between our case-case GWAS and that of case-control BD. Conclusions; We find that MDD and BD, including BD with a depressive onset, are genetically distinct. Further, our findings support the hypothesis that Controls – MDD — BD primarily lie on a continuum of genetic risk. Future studies with larger and richer samples will likely yield a better understanding of these findings and enable the development of better genetic predictors distinguishing BD and, importantly, BD with depressive onset from MDD