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Euthymic bipolar disorder (euBD) patients exhibit deficits in neurocognitive and social cognitive functioning compared to healthy controls (HCs). Our prior research has shown that the excitatory/inhibitory (E/I) imbalance in the default mode network (DMN) is linked to executive function in euBD. Neurocognitive impairments are associated with social cognition deficits in individuals with mental disorders. Given this connection, this study posits E/I imbalance within the DMN is associated with social cognition, with executive function as a mediator.
Methods
Seventy-five HCs and 49 euBD individuals were recruited. Using the emotion recognition task, Diagnostic Analysis of Nonverbal Accuracy 2-Taiwan version (DANVA-2-TW) and cognitive flexibility task, Wisconsin Card Sorting Test (WCST), we assessed emotion recognition and prefrontal function. Proton magnetic resonance spectroscopy (1H-MRS) measured metabolites in the posterior cingulate cortex (PCC) and medial prefrontal cortex/anterior cingulate cortex (mPFC/ACC), quantifying excitatory glutamate+glutamine (Glx) and inhibitory GABA to calculate the E/I ratio.
Results
euBD patients showed poorer emotion recognition (p = 0.020) and poorer cognitive flexibility (fewer WCST categories completed, p = 0.002). A negative association was found between emotion recognition and the E/I ratio in the mPFC/ACC of the BD patients (r = −0.30, p = 0.034), which was significantly mediated by cognitive flexibility (Z = −2.657, p = 0.007).
Conclusion
The BD patients demonstrate deficits in emotion recognition, linked to an altered E/I balance in the prefrontal cortex, and the cognitive flexibility, a key aspect of executive function, mediates the impact of the E/I ratio on emotion recognition accuracy in euBD patients.
Swirling waves frequently occur in a three-dimensional tank under a nearly resonant excitation with oblique excitation angle. The oblique excitation produces two excitation components and the secondary component triggers rotational waves. The detailed mechanism of the switch in circular direction is clearly described in this study. The evolution of the hydrodynamic forces (Fz) on the tank walls presents a beating phenomenon and the switch direction always occurs at the peak and trough of the envelope of the Fz history. The external excitation moment changes the circulation intensity, and finally the swirling wave becomes a single-direction wave, but only for a short time. The profile of the single-direction wave was determined by the dominant sloshing mode and the instantaneous tank motion was found to be a key factor to determine the consequent swirling flow circulating direction.
Supported by (1) medical research grants CMRPG3C0041/42 from Chang Gung Memorial Hospital and NRRPG2H0031 from Ministry of Science and Technology, Taiwan to Chemin Lin (2) NMRPG3G6031/32 from Ministry of Science and Technology, Taiwan to Shwu-Hua, Lee (3) the KKHo International Charitable Foundation to Tatia Lee.
Introduction:
Suicide rate tends to peak in old age, and major depression is the most salient risk factor for late-life suicide. However, few studies have focused on the neuroscientific facet of suicide in the context of late-life depression (LLD).
Methods:
We recruited 114 participants of LLD (28 with history of suicide attempt and 86 without) and 47 elderly controls. They received MRI scanning and behavioral assessment. White matter hyperintensity (WMH) was quantified by an automated segmentation algorithm and graph theoretical analysis was applied to resting-state fMRI. We used ANCOVA to compare group difference in WMH loading and multivariate generalized linear model to compare global and local topological parameters in fMRI signals, controlling for demographics. Partial correlation was conducted between imaging parameters and behavioral data in group of suicide attempters.
Results:
We found significant higher WMH in suicide attempters than those of LLD without suicide attempts and elderly controls (F =7.091; p = 0.001). Suicide attempters also had increased betweenness centrality (BC) in right superior occipital gyrus (SOG) (Bonferroni corrected), right precuneus (False positive corrected) and right superior temporal gyrus (uncorrected) and decreased BC in left hippocampus (uncorrected). In suicide attempters, higher BC in right SOG correlated with higher WMH, higher depression severity, higher illness awareness and insight, and lower cognitive function (digit backward), while higher BC in right precuneus correlated with higher decrease awareness and insight and higher cognitive function (digit backward).
Conclusion:
Resonating with the vascular hypothesis in LLD, higher WMH was found in those having history of suicide attempts. However, the re-organized brain topology changes are related with divergent cognitive function and convergent heightened disease insight.
The Doba gabbro was collected from an exploration well through the Cretaceous Doba basin of southern Chad. The gabbro is composed mostly of plagioclase, clinopyroxene and Fe–Ti oxide minerals and displays cumulus mineral textures. Whole-rock 40Ar–39Ar step-heating geochronology yielded a Late Permian plateau age of 257 ± 1 Ma. The major and trace elemental geochemistry shows that the gabbro is tholeiitic in composition and has trace element ratios (i.e. La/YbN > 7; Sm/YbPM > 3.4; Nb/Y > 1; Zr/Y > 5) indicative of a basaltic melt derived from a garnet-bearing mantle source. The moderately enriched Sr–Nd isotopes (i.e. ISr = 0.70495 to 0.70839; ɛNd(T) = −1.0 to −1.3) fall within the mantle array (i.e. OIB-like) and are similar to other Late Permian plutonic rocks of North-Central Africa (i.e. ISr = 0.7040 to 0.7070). The enriched isotopic composition of the Doba gabbro contrasts with the more depleted compositions of the spatially associated Neoproterozoic post-Pan-African within-plate granites. The contrasting Nd isotope composition between the older within-plate granites and the younger Doba gabbro indicates that different mantle sources produced the rocks and thus may mark the southern boundary of the Saharan Metacraton.
Glycogen stored in skeletal muscle is the main fuel for endurance exercise. The present study examined the effects of oral hydroxycitrate (HCA) supplementation on post-meal glycogen synthesis in exercised human skeletal muscle. Eight healthy male volunteers (aged 22·0 (se 0·3) years) completed a 60-min cycling exercise at 70–75 % and received HCA or placebo in a crossover design repeated after a 7 d washout period. They consumed 500 mg HCA or placebo with a high-carbohydrate meal (2 g carbohydrate/kg body weight, 80 % carbohydrate, 8 % fat, 12 % protein) for a 3-h post-exercise recovery. Muscle biopsy samples were obtained from vastus lateralis immediately and 3 h after the exercise. We found that HCA supplementation significantly lowered post-meal insulin response with similar glucose level compared to placebo. The rate of glycogen synthesis with the HCA meal was approximately onefold higher than that with the placebo meal. In contrast, GLUT4 protein level after HCA supplementation was significantly decreased below the placebo level, whereas expression of fatty acid translocase (FAT)/CD36 mRNA was significantly increased above the placebo level. Furthermore, HCA supplementation significantly increased energy reliance on fat oxidation, estimated by the gaseous exchange method. However, no differences were found in circulating NEFA and glycerol levels with the HCA meal compared with the placebo meal. The present study reports the first evidence that HCA supplementation enhanced glycogen synthesis rate in exercised human skeletal muscle and improved post-meal insulin sensitivity.
Solder pots used in wave soldering are usually made using different kinds of steel. Dissolution and interfacial reactions of the Fe substrate in molten Sn-Pb and Sn-Cu solders are investigated in this study. FeSn2 phase is formed in the Sn-0.7wt%Cu/Fe couples reacted at 250, 400, and 500 °C, as well as in the Sn-37wt%Pb/Fe couples reacted at 250 and 400 °C. The activation energies of formation are 123 and 121 kJ/mol in the Sn-Cu/Fe and Sn-Pb/Fe couples, respectively. FeSn phase is the reaction product in the Sn-37wt%Pb/Fe couples reacted 500 °C. The dissolution rates of Fe in the Sn-0.7wt%Cu melt are much higher than those in-the Sn-37wt%Pb melt. The FeSn2 phase layer in the Sn-Cu/Fe couple is not as dense as that in the Sn-Pb/Fe couple and accounts for the very different dissolution rates. Detachment of the reaction FeSn2 phase into the solder matrix is observed in the Sn-Cu/Fe couples, and is a potential contaminant source in wave soldering.
In this work, the charge-trapping distributions of polysilicon-oxide-nitride-oxide-silicon (SONOS) structure are studied. The trapping energy level of SiNx films with different composition ratio deposited by low-pressure chemical vapor deposition (LPCVD) were first characterized by photoluminescence (PL) measurement. Moreover, using F-N/CHE program and charge pumping techniques, the vertical location and the lateral distribution of programmed charges are investigated in the nitride films with different composition ratio. The study offers strong evidence that the density of charge-trapping levels in the Si-rich nitride is higher than the standard nitride. A simple qualitative model and calculation explains that the trapping level distributions in the SiNx films are shallower by increasing relative Si-content. Furthermore, we have observed the nitride trap vertical location was changed by adjusted Si/N composition ratio. And the lateral distribution of hot electron programmed charges in the modified nitride is broader than that in the standard nitride because it offered more charge-trapping sites and shallower charge-trapping levels. In summary, the study can help researchers to understand the nitride charge-trapping mechanism and the analysis of optical/electrical characteristics.
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