Medial Frontal White and Gray Matter Contributions to General Intelligence

The medial orbitofrontal cortex (mOFC) and rostral anterior cingulate cortex (rACC) are part of a wider neural network that plays an important role in general intelligence and executive function. We used structural brain imaging to quantify magnetic resonance gray matter volume and diffusion tensor white matter integrity of the mOFC-rACC network in 26 healthy participants who also completed neuropsychological tests of intellectual abilities and executive function. Stochastic tractography, the most effective Diffusion Tensor Imaging method for examining white matter connections between adjacent gray matter regions, was employed to assess the integrity of mOFC-rACC pathways. Fractional anisotropy (FA), which reflects the integrity of white matter connections, was calculated. Results indicated that higher intelligence correlated with greater gray matter volumes for both mOFC and rACC, as well as with increased FA for left posterior mOFC-rACC connectivity. Hierarchical regression analyses revealed that DTI-derived FA of left posterior mOFC-rACC uniquely accounted for 29%–34% of the variance in IQ, in comparison to 11%–16% uniquely explained by gray matter volume of the left rACC. Together, left rACC gray matter volume and white matter connectivity between left posterior mOFC and rACC accounted for up to 50% of the variance in general intelligence. This study is to our knowledge the first to examine white matter connectivity between OFC and ACC, two gray matter regions of interests that are very close in physical proximity, and underscores the important independent contributions of variations in rACC gray matter volume and mOFC-rACC white matter connectivity to individual differences in general intelligence

DECIGO pathfinder

DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) which is a future space gravitational wave antenna. DECIGO is expected to provide us fruitful insights into the universe, in particular about dark energy, a formation mechanism of supermassive black holes, and the inflation of the universe. Since DECIGO will be an extremely large mission which will formed by three drag-free spacecraft with 1000m separation, it is significant to gain the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. The conceptual design and current status of the first milestone mission, DPF, are reviewed in this article

The status of DECIGO

DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) is the planned Japanese space gravitational wave antenna, aiming to detect gravitational waves from astrophysically and cosmologically significant sources mainly between 0.1 Hz and 10 Hz and thus to open a new window for gravitational wave astronomy and for the universe. DECIGO will consists of three drag-free spacecraft arranged in an equilateral triangle with 1000 km arm lengths whose relative displacements are measured by a differential Fabry-Perot interferometer, and four units of triangular Fabry-Perot interferometers are arranged on heliocentric orbit around the sun. DECIGO is vary ambitious mission, we plan to launch DECIGO in era of 2030s after precursor satellite mission, B-DECIGO. B-DECIGO is essentially smaller version of DECIGO: B-DECIGO consists of three spacecraft arranged in an triangle with 100 km arm lengths orbiting 2000 km above the surface of the earth. It is hoped that the launch date will be late 2020s for the present

Countercurrent Flow Limitation at the Junction between the Surge Line and the Pressurizer of a PWR

An experimental study on countercurrent flow limitation (CCFL) in vertical pipes is carried out. Effects of upper tank geometry and water levels in the upper and lower tanks on CCFL characteristics are investigated for air-water two-phase flows at room temperature and atmospheric pressure. The following conclusions are obtained: (1) CCFL characteristics for different pipe diameters are well correlated using the Kutateladze number if the tank geometry and the water levels are the same; (2) CCFL occurs at the junction between the pipe and the upper tank both for the rectangular and cylindrical tanks, and CCFL with the cylindrical tank occurs not only at the junction but also inside the pipe at high gas flow rates and small pipe diameters; (3) the flow rate of water entering into the vertical pipe at the junction to the rectangular upper tank is lower than that to the cylindrical tank because of the presence of low frequency first-mode sloshing in the rectangular tank; (4) increases in the water level in the upper tank and in the air volume in the lower tank increase water penetration into the pipe, and therefore, they mitigate the flow limitation

White matter integrity and gray matter volume.

<p>Abbreviations: OFC, orbitofrontal cortex; ACC, anterior cingulate cortex, mOFC, medial orbitofrontal cortex; rACC, rostral part of anterior cingulate cortex.</p>a)<p>Mean fractional anisotropy values for bilateral mOFC-rACC white matter connections.</p>b)<p>Gray matter volumes for the ROIs (i.e. anterior mOFC, posterior mOFC, and rACC).</p><p>White matter integrity and gray matter volume.</p

Correlations between the ROI volumes or mOFC-rACC FA and WIAS-III full scale IQ.

<p>Abbreviations: ROI, region of interest; WAIS-III, Wechsler Adult Intelligence Scale-Third Edition (WAIS-III; Wechsler, 1997); IQ, intelligent quotient; FA, fractional anisotropy; mOFC, medial orbitofrontal cortex; rACC, rostral anterior cingulate cortex</p><p>Correlations between the ROI volumes or mOFC-rACC FA and WIAS-III full scale IQ.</p

Scatter plot of correlations between WAIS-III Full Scale IQ and left posterior mOFC-rACC FA values (N = 25).

<p>Scatter plot of correlations between WAIS-III Full Scale IQ and left posterior mOFC-rACC FA values (N = 25).</p

The stochastic cloud connecting the medial orbitofrontal cortex (mOFC) and the rostral anterior cingulate cortex (rACC).

<p>The red structure is the mOFC, the purple is the rACC, and the light green is the stochastic cloud connecting the mOFC and rACC.</p

Neuropsychological test scores.

<p>Abbreviations: WAIS-III, Wechsler Adult Intelligence Scale-Third Edition (WAIS-III; Wechsler, 1997); IQ, intelligent quotient; WCST, Wisconsin Card Sorting Test (WCST; Heaton, 1981); TMT, Trail Making Test (TMT; Reitan, 1992).</p><p>Neuropsychological test scores.</p