Fabrication and Evaluation of N-Channel GaN Metal-Oxide-Semiconductor Field-Effect Transistors Based on Regrown and Implantation Methods.

We have demonstrated the enhancement-mode n-channel gallium nitride (GaN) metal-oxide field-effect transistors (MOSFETs) on homoepitaxial GaN substrates using the selective area regrowth and ion implantation techniques. Both types of MOSFETs perform normally off operations. The GaN-MOSFETs fabricated using the regrowth method perform superior characteristics over the other relative devices fabricated using the ion implantation technique.

Ultrathin silicon oxynitride layer on GaN for dangling-bond-free GaN/insulator interface.

Despite the scientific and technological importance of removing interface dangling bonds, even an ideal model of a dangling-bond-free interface between GaN and an insulator has not been known. The formation of an atomically thin ordered buffer layer between crystalline GaN and amorphous SiO would be a key to synthesize a dangling-bond-free GaN/SiO interface. Here, we predict that a silicon oxynitride (SiON) layer can epitaxially grow on a GaN(0001) surface without creating dangling bonds at the interface.

Reduced white matter integrity as a neural correlate of social cognition deficits in schizophrenia.

Background: The pathology of schizophrenia is thought to involve multiple gray and white matter regions. A number of studies have revealed impaired social cognition in schizophrenia. Some evidence suggests an association of this social cognition deficit with gray matter reductions in 'social brain' areas.

Brain volume and dysexecutive behavior in schizophrenia.

Objective: Behaviors associated with frontal/executive impairments are common in patients with schizophrenia. Our aim was to reconfirm that morphological brain abnormalities in schizophrenia patients would overlap the areas underpinning frontal systems behavior, and examine whether any specific association exists between abnormalities of brain structures and frontal behavioral deficits in schizophrenia patients.

Method: Twenty-six schizophrenia patients and 26 matched healthy controls underwent structural magnetic resonance imaging and their frontal function was assessed by a self-rating questionnaire, Frontal Systems Behavior Scale (FrSBe).

Reduced white matter integrity correlated with cortico-subcortical gray matter deficits in schizophrenia.

Background: The pathology of schizophrenia is thought to involve multiple brain regions and the connections among them. Although a number of MRI studies have demonstrated gray matter reductions and abnormal white matter integrity in schizophrenia, to date no study has investigated their association in the whole brain.

Methods: Twenty-seven schizophrenia patients and 33 healthy controls were recruited.

Theory of mind and frontal lobe pathology in schizophrenia: a voxel-based morphometry study.

Impaired ability to infer the mental states of others (theory of mind; ToM) is considered to be a key contributor to the poor social functioning of patients with schizophrenia. Although neuroimaging and lesion studies have provided empirical evidence for the neural basis of ToM ability, including the involvement of several prefrontal and temporal structures, the association between pathology of these structures and ToM impairment in schizophrenia patients is less well understood. To address this issue, we investigated structural brain abnormalities and ToM impairment in patients with schizophrenia, and examined the relationship between them.

Female specific anterior cingulate abnormality and its association with empathic disability in schizophrenia.

Evidence suggests that impairments of empathy are present in schizophrenia and that such deficits lead to social dysfunction. However, the relationship between brain morphological abnormalities of the disorder and empathic disabilities has not been fully investigated. As the anterior cingulate cortex (ACC) is one of the critical structures for empathy processing, the pathology of this structure might be a major source of social dysfunction, including interpersonal miscommunication in schizophrenia.

Structural abnormalities of the adhesio interthalamica and mediodorsal nuclei of the thalamus in schizophrenia.

Objective: Several studies have suggested the existence of thalamic volume reduction in patients with schizophrenia. However, the precise locus of volume reduction within the thalamus has scarcely been investigated. On the other hand, underdevelopment of the adhesio interthalamica [AI; Danos, P.

Anterior and posterior cingulum abnormalities and their association with psychopathology in schizophrenia: a diffusion tensor imaging study.

Evidence suggests that a disruption in limbic system network integrity and, in particular, the cingulate gyrus may play a role in the pathophysiology of schizophrenia. The cingulum bundles (CBs; posterior and anterior) are the most prominent white matter tracts in the limbic system, furnishing both input and output to the cingulate gyrus . In previous diffusion tensor imaging (DTI) studies, abnormal integrity has been demonstrated in the anterior CB portion, but not the posterior, in schizophrenia.

Anterior cingulate pathology and social cognition in schizophrenia: a study of gray matter, white matter and sulcal morphometry.

The anterior cingulate gyrus (ACG) is a critical structure for social cognitive processing; the pathology of this structure might be a major source of social dysfunction in schizophrenia. Multiple structural abnormalities of the ACG have been demonstrated in schizophrenia including changes in gray matter volume, white matter microstructures and macroscopic sulcal morphology. However, the interrelationships among these different abnormalities have not been investigated.