Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders

Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyperactivity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.National Institutes of HealthVoRSUNY DownstatePsychiatry and Behavioral SciencesInstitute for Genomics in HealthN/

Self-Consistent Subband Calculations of Al<sub>x</sub>Ga<sub>1-x</sub>N/(AlN)/GaN-Based High Electron Mobility Transistor

In this paper, there is an attempt to present the two dimensional electron gas (2DEG) transport characteristics of AlxGa1-xN/(AlN)/GaN-based High Electron Mobility Transistor (HEMT) using a self-consistent numerical method for calculating the conduction-band profile and subband structure. The subband calculations take into account the piezoelectric and spontaneous polarization effects and the Hartree and exchange-correlation interaction. Here the dependency of conduction band profile, subband energies, 2DEG sheet concentration and sheet resistance on various Al mole fractions of AlxGa1-xN barrier layer are presented by incorporating simulation as well as available experimental data. Introduction of very thin binary AlN layer at the heterojunction of AlxGa1-xN/GaN resulting high mobility at high sheet charge densities by increasing the effective and decreasing alloy disorder scattering. Devices based on this structure exhibit good DC and RF performance as an increase of . Owing to high 2DEG density , the proposed device leads to operate in microwave and millimeter wave applications.</jats:p

A Comparative 2DEG Study of InxAl1-xN/ (In, Al, Ga) N/GaN-based HEMTs

AbstractIn this paper a novel InxAl1-xN/GaN heterostructure device is proposed by introducing a thin binary layer of strained (In, Al, Ga)-N channel at the heterointerface. The spontaneous polarization fields of III-N ternary alloys are derived as per Vegard's rule. The band engineering leading to the formation of two dimensional electron gas (2DEG) has been discussed by simulating the different heterostructures by solving 1D Schrodinger and Poisson's equation self-consistently and the energy bands are calculated. Comparative studies of electronic transport properties of charge carriers in the 2DEG are also investigated for the different proposed structures. Charge concentrations throughout the structure were analyzed which show the confinement of charge carriers in the Quantum Well/2DEG at the heterointerface are maximum. The electric field variation with structure depth from surface to bottom and as a function of 2DEG density has also been investigated. High 2DEG density ensures high electric field is realized from the 2DEG study of different proposed heterostructures