Browsing by Author "Chen H."

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    Configuration mixing of angular-momentum-projected triaxial relativistic mean-field wave functions. II. Microscopic analysis of low-lying states in magnesium isotopes
    (2011) Yao J.M.; Mei H.; Chen H.; Meng J.; Ring P.; Vretenar D.
    The recently developed structure model that uses the generator coordinate method to perform configuration mixing of angular-momentum projected wave functions, generated by constrained self-consistent relativistic mean-field calculations for triaxial shapes (3DAMP+GCM), is applied in a systematic study of ground states and low-energy collective states in the even-even magnesium isotopes 20-40Mg. Results obtained using a relativistic point-coupling nucleon-nucleon effective interaction in the particle-hole channel and a density-independent δ interaction in the pairing channel are compared to data and with previous axial 1DAMP+GCM calculations, both with a relativistic density functional and the nonrelativistic Gogny force. The effects of the inclusion of triaxial degrees of freedom on the low-energy spectra and E2 transitions of magnesium isotopes are examined. © 2011 The American Physical Society.
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    Disrupted functional connectivity in social anxiety disorder: a resting-state fMRI study
    (2011-05-25) Ding J.; Chen H.; Qiu C.; Liao W.; Warwick, James M.; Duan X.; Zhang W.; Gong Q.
    Dysfunction of the corticolimbic circuitry has been highlighted in social anxiety disorder (SAD) during social stimuli. However, few studies have investigated functional connectivity in SAD during the resting state, which may improve our understanding of SAD pathophysiology. The aim of this study was to investigate whether whole-brain functional connectivity might be aberrant in SAD patients, and if so, whether these changes are related to the measured clinical severity. Seventeen SAD patients and 19 healthy controls participated in resting-state functional magnetic resonance imaging. The brain was first divided into 90 paired brain regions and functional connectivity was then estimated by temporal correlation between each of these regions. Furthermore, connections that were significantly disrupted in SAD patients were correlated with clinical severity measured using the Liebowitz Social Anxiety Scale. Compared with healthy controls, SAD patients showed decreased positive connections within the frontal lobe and decreased negative connections between the frontal and occipital lobes. In particular, the weaker negative connections between the frontal lobe, which mainly involved the right median prefrontal cortex, and the occipital lobe had a significant positive correlation with the severity of SAD symptoms. The results support the hypothesis that some abnormalities of functional connectivity exist in SAD patients, which relate to the frontal cortex and occipital cortex. In addition, decreased functional connectivity between the frontal and occipital lobes and within the frontal lobe might be related to abnormal information processing and reflect disturbed neural organization resulting in defective social cognition, which could represent an early imaging biomarker for SAD. © 2011 Elsevier Inc. All rights reserved.
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    Energy density functional analysis of shape evolution in N=28 isotones
    (2011) Li Z.P.; Yao J.M.; Vretenar D.; Niksic T.; Chen H.; Meng J.