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BackgroundOur understanding of the complex relationship between schizophrenia symptomatology and etiological factors can be improved by studying brain-based correlates of schizophrenia. Research showed that impairments in value processing and executive functioning, which have been associated with prefrontal brain areas [particularly the medial orbitofrontal cortex (MOFC)], are linked to negative symptoms. Here we tested the hypothesis that MOFC thickness is associated with negative symptom severity.MethodsThis study included 1985 individuals with schizophrenia from 17 research groups around the world contributing to the ENIGMA Schizophrenia Working Group. Cortical thickness values were obtained from T1-weighted structural brain scans using FreeSurfer. A meta-analysis across sites was conducted over effect sizes from a model predicting cortical thickness by negative symptom score (harmonized Scale for the Assessment of Negative Symptoms or Positive and Negative Syndrome Scale scores).ResultsMeta-analytical results showed that left, but not right, MOFC thickness was significantly associated with negative symptom severity (β std = -0.075; p = 0.019) after accounting for age, gender, and site. This effect remained significant (p = 0.036) in a model including overall illness severity. Covarying for duration of illness, age of onset, antipsychotic medication or handedness weakened the association of negative symptoms with left MOFC thickness. As part of a secondary analysis including 10 other prefrontal regions further associations in the left lateral orbitofrontal gyrus and pars opercularis emerged.ConclusionsUsing an unusually large cohort and a meta-analytical approach, our findings point towards a link between prefrontal thinning and negative symptom severity in schizophrenia. This finding provides further insight into the relationship between structural brain abnormalities and negative symptoms in schizophrenia.

ObjectiveBased on the role of the superior temporal gyrus (STG) in auditory processing, language comprehension and self-monitoring, this study aimed to investigate the relationship between STG cortical thickness and positive symptom severity in schizophrenia.MethodThis prospective meta-analysis includes data from 1987 individuals with schizophrenia collected at seventeen centres around the world that contribute to the ENIGMA Schizophrenia Working Group. STG thickness measures were extracted from T1-weighted brain scans using FreeSurfer. The study performed a meta-analysis of effect sizes across sites generated by a model predicting left or right STG thickness with a positive symptom severity score (harmonized SAPS or PANSS-positive scores), while controlling for age, sex and site. Secondary models investigated relationships between antipsychotic medication, duration of illness, overall illness severity, handedness and STG thickness.ResultsPositive symptom severity was negatively related to STG thickness in both hemispheres (left: βstd = -0.052; P = 0.021; right: βstd = -0.073; P = 0.001) when statistically controlling for age, sex and site. This effect remained stable in models including duration of illness, antipsychotic medication or handedness.ConclusionOur findings further underline the important role of the STG in hallmark symptoms in schizophrenia. These findings can assist in advancing insight into symptom-relevant pathophysiological mechanisms in schizophrenia.

Subcortical structures, which include the basal ganglia and parts of the limbic system, have key roles in learning, motor control and emotion, but also contribute to higher-order executive functions. Prior studies have reported volumetric alterations in subcortical regions in schizophrenia. Reported results have sometimes been heterogeneous, and few large-scale investigations have been conducted. Moreover, few large-scale studies have assessed asymmetries of subcortical volumes in schizophrenia. Here, as a work completely independent of a study performed by the ENIGMA consortium, we conducted a large-scale multisite study of subcortical volumetric differences between patients with schizophrenia and controls. We also explored the laterality of subcortical regions to identify characteristic similarities and differences between them. T1-weighted images from 1680 healthy individuals and 884 patients with schizophrenia, obtained with 15 imaging protocols at 11 sites, were processed with FreeSurfer. Group differences were calculated for each protocol and meta-analyzed. Compared with controls, patients with schizophrenia demonstrated smaller bilateral hippocampus, amygdala, thalamus and accumbens volumes as well as intracranial volume, but larger bilateral caudate, putamen, pallidum and lateral ventricle volumes. We replicated the rank order of effect sizes for subcortical volumetric changes in schizophrenia reported by the ENIGMA consortium. Further, we revealed leftward asymmetry for thalamus, lateral ventricle, caudate and putamen volumes, and rightward asymmetry for amygdala and hippocampal volumes in both controls and patients with schizophrenia. Also, we demonstrated a schizophrenia-specific leftward asymmetry for pallidum volume. These findings suggest the possibility of aberrant laterality in neural pathways and connectivity patterns related to the pallidum in schizophrenia.

Gamma-ray transition edge sensors (TESs) are intensively studied not only to measure isotopic composition of nuclear materials but to monitor transuranic radionuclides inside the human body. We have recently proposed a thick-trilayer membrane as an alternative to silicon-nitride (Si x N y ) single-layer ones. It consists of silicon dioxide (SiO 2 ), Si x N y , and SiO 2 layers. Their total thickness is 6.9 μ m and exhibits almost the same thermal conductance as conventional Si x N y ones with 1- μ m thickness. The thick-trilayer membrane is expected to have better mechanical strength against implementing heavy-bulk absorbers. In this paper, the gamma-ray TES with the thick-trilayer membrane is used to carry out the spectroscopy for the nuclear radiation source. Neptunium-237 and its decay product Protactinium-233 emit 86.5 and 86.6-keV lines, respectively, and they are clearly resolved by four pixels with the full-width-half-maximum (FWHM) resolution of ( 43.7 ± 0.9 ) eV. Furthermore, their intensity ratio agrees with the radioactive equilibrium between the two nuclides. Our experimental results predict that a vast array of pixel formats will reduce the statistical uncertainty in less measuring time. [ABSTRACT FROM AUTHOR]

A fully functioning programmable voltage standard chips with double- and triple-stacked MoSi2 barrier Josephson junctions with over 100,000 junctions operating simultaneously on a 1cm x 1 cm chip are presented. The maximum output voltages of the double- and triple-stacked chips are 2.6 V and 3.9 V, with respective operating current margins of 2 mA and 1 mA.

Thick membranes of the gamma-ray transition-edge sensor (γ -TES) generally exhibit great mechanical strength and can support a bulk metal absorber typical for γ -TES. However, for conventional silicon-nitride (SixNy) membranes, thermal conductance (G) is proportional to the thickness, indicating that thicker membranes provide larger thermal-fluctuation noise in TESs. We propose a thick-trilayer membrane consisting of the silicon oxide (SiO2), SixNy, and SiO2 layers. The SixNy layer accounts for 5.8 μm of the total 6.9 μm, and thus, it is expected to be hard compared with conventional SixNy membranes with a typical thickness below 1 μm. G of the trilayer membrane is characterized as a function of heat-transport distance (L), and the G-L relation follows that of the intermediate model between ballistic and diffusive transports. Resulting G of the thick-trilayer membrane is 1.1–1.7 nW/K, which is not far from the one reported by conventional SixNy membranes. Gamma-ray spectroscopy around 93 keV is carried out based on series biased 5-pixels TES. The best full-width-half-maximum energy resolution among all pixels under characterization is 43.1 ± 1.6 eV for 93-keV, which is close to the median value of a state-of-the-art 236-pixels γ -TES in the literature. The measured low-frequency noise can be represented by theoretical phonon noise and its excess component with the same order as conventional ones. The thick-trilayer membrane is demonstrated to be able to work without any problems in a γ -TES regime. [ABSTRACT FROM AUTHOR]

Vertically stacked Josephson junctions with very thin intermediate electrodes are fabricated on a Si wafer using the direct current magnetron sputtering method. Experiments are performed to determine the occurrence of synchronous switching of the junctions and the magnetic field dependence of the critical currents. Results indicate that synchronous switching takes place between the lower and upper junctions. Three types of responses for an external magnetic field are also observed.

Fabrication of stacked double and triple Josephson junctions with NbN electrodes and TiN[subscript x] barriers is described and discussed.