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Objective To explore the multiple specific biomarkers and cognitive compensatory mechanisms of mild traumatic brain injury (mTBI) patients at recovery stage. Methods The experiment was performed in two sections. In Section I, using event-related potential, event-related oscillation and spatial phase-synchronization, we explored neural dynamics in 24 volunteered healthy controls (HC) and 38 patients at least 6 months post-mTBI (19 with epidural hematoma, EDH; 19 with subdural hematoma, SDH) during a Go/NoGo task. In Section II, according to the neuropsychological scales, patients were divided into sub-groups to assess these electroencephalography (EEG) indicators in identifying different rehabilitation outcomes of mTBI. Results In Section I, mean amplitudes of NoGo-P3 and P3d were decreased in mTBI patients relative to HC, and NoGo-theta power in the non-injured hemisphere was decreased in SDH patients only. In Section II, patients with chronic neuropsychological defects exhibited more serious impairments of intra-hemispheric connectivity, whereas inter-hemispheric centro-parietal and frontal connectivity were enhanced in response to lesions. Conclusions EEG distinguished mTBI patients from healthy controls, and estimated different rehabilitation outcomes of mTBI. The centro-parietal and frontal connectivity are the main compensatory mechanism for the recovery of mTBI patients. Significance EEG measurements and network connectivity can track recovery process and mechanism of mTBI.

The diagrams of intergranular volume versus cementation volume brought up by Houseknecht (1987) and Ehrenberg (1989), are extensively used around the globe to assess the relative significance of compaction and cementation to porosity reduction in sandstones. However, Houseknecht (1987) overlooked the fact that the bulk sediment volume is dynamically compressed during burial, which directly leads to deviation in evaluating original porosity loss. The present discussion is based on the theoretical and contrastive analysis. These analyses indicate the compactional porosity loss calculated by Ehrenberg's (1989) method is always greater than Houseknecht's (1987) method with a maximum difference of 12.7%. In contrast, the cementation porosity loss using Ehrenberg's (1989) method is always less than Houseknecht's (1987). Besides, the demonstration based on the data of Wei et al. (2020) also supports Ehrenberg (1989). Therefore, the method proposed by Ehrenberg (1989) should be highly recommended to be granted as a reference far and wide.

To obtain the pollution agglomeration characteristics of insulators and its effect mechanism of Ultra High-Voltage DC transmission lines under natural sedimentary condition, a natural pollution accumulation system was set up and used to analyze the micro-shape features of the surface insulators on different conditions. The experimental results show that the surface pollution is respectively distributed as chain and granular shapes on the DC charged insulator and electrically neutral insulator, which indicates that the pollution agglomeration characteristics are influenced by the DC electric field significantly. Meanwhile, the radius of the pollution particles on the DC charged insulator is larger than that on the uncharged insulator. Based on the thermodynamics and electrostatics theory, this paper proposed the model of electric dipole between aerosol groups to explain the characteristics of the pollution distribution on the surface of the DC charged insulator and revealed the mechanism of aerosol particles radius affected by DC electric field. The conclusions of this paper can provide an experimental and theoretical basis for the UHV DC external insulation pollution characteristics and insulator flashover.

For HVAC and HVDC transmission lines which are partially in parallel in one corridor, coupling parameters between AC and DC transmission lines can be changed due to the length of extension sections which are not in parallel. And the generated electromagnetic coupling components at the two terminals of the DC line contain the effects of line parameters of extension sections. In this paper, the coupling components on the DC line, not all of which is in parallel with the AC line are studied in detail. The DC line is longer than the AC line and it may have extension sections on the both sides. Firstly, a new methodology is presented to calculate the coupling components of HVAC line upon HVDC line in the above situation. Then, the correctness and applicability of this method is illustrated and validated through a case study. Meanwhile, the key factors affecting the coupling between the AC and DC lines are analyzed. Finally, some suggestions have been proposed to provide as a construction reference which aims to optimize the electromagnetic coupling components on the DC line.

Hydrogen sulfide as the third endogenous gaseous mediator had protective effects against traumatic brain injury-induced neuronal damage in mice. However, the exact pathophysiological mechanism underlying traumatic brain injury is complicated and the protective role of H2S is not yet fully known. Therefore, we combined the mechanical injury (scratch) with secondary injury including metabolic impairment (no glucose) together to investigate the underlying cellular mechanism of hydrogen sulfide in vitro models of traumatic brain injury. In the present study, we found that H2S could prevent the scratch-induced decrease in the expression of cystathionine-β-synthetase, a key enzyme involved in the source of hydrogen sulfide, and endogenous hydrogen sulfide generation in PC12 cells. We also found that hydrogen sulfide could prevent scratch-induced cellular injury, alteration of mitochondrial membrane potential, intracellular accumulation of reactive oxygen species and cell death (autophagic cell death and apoptosis) in PC12 cells. It was also found that blocking PI3K/AKT pathway by LY294002, abolished the protection of H2S against scratch-induced cellular reactive oxygen species level and NRF2 accumulation and function in the nucleus. These results suggest that hydrogen sulfide protects against cell damage induced by scratch injury through modulation of the PI3K/Akt/Nrf2 pathway. This study raises the possibility that hydrogen sulfide may have therapeutic efficacy in traumatic brain injury.