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Objective To evaluate the improvement of superficial temporal artery⁃middle cerebral artery (STA⁃MCA) bypass combined with encephalo⁃myo⁃synangiosis (EMS) on cognitive function in patients with moyamoya disease (MMD). Methods Total 37 patients with MMD treated with STA⁃MCA+EMS in Tianjin Medical University General Hospital from July 2017 to June 2020 were reviewed. Mini⁃Mental State Examination (MMSE), Auditory Verbal Learning Test (AVLT), Trail Making Test⁃A (TMT⁃A), Trail Making Test⁃B (TMT⁃B), Verbal Fluency Test (VFT) and Rey⁃Osterrieth Complex Figure Test (ROCFT) were used to evaluate overall cognitive function, memory, attention, executive function, language function and visuospatial function in all patients one week before surgery and 6 months after surgery. Results Compared with one week before surgery, the MMSE score [24 (23, 26) score vs. 25.00 (23.50, 27.00) score; Z=⁃4.201, P=0.000] and ROCFT score [28 (23, 30) score vs. 31.00 (28.50, 32.00) score; Z=⁃3.968, P=0.004] increased, while the TMT⁃A test [69.00 (56.00, 87.50) s vs. 42 (37, 48) s; Z=⁃5.144, P=0.002] and TMT⁃B test [177 (168, 190) s vs. 138 (133, 144) s; Z=⁃5.309, P=0.001] decreased at 6 months after surgery. There was no statistic difference of AVLT⁃1R (Z=⁃1.595, P=0.113), AVLT⁃5R (Z=⁃1.573, P=0.121) and VFT (Z=⁃1.616, P=0.124) before and after surgery. Conclusions STA⁃MCA+EMS can improve the overall cognitive function, attention, executive function and visuospatial ability of patients with MMD, but has no significant effect on short⁃term memory, long⁃term memory and language function, and can improve cognitive function and the quality of life.

Using density functional theory in the noncollinear approximation, the behavior of quantum states of hole qubits in a Ge/Co:ZnO system was studied in this work. A detailed analysis of the electronic structure and the distribution of total charge density and hole states was carried out. It was shown that in the presence of holes, the energetically more favorable quantum state is the state |0˃, in contrast to the state |1˃ when there is no hole in the system. The favorability of hole states was found to be dependent on the polarity of the applied electric field.

Byzantine fault-tolerant algorithm is vital to ensure the distributed system such as blockchain reaching consistency.The performance of algorithm affects the security and stability of the system.In view of the low efficiency and lack of incentive mechanism of existing consensus algorithms,a rational practical Byzantine fault-tolerant consensus algorithm with evolutionary game is proposed.Firstly,the trustworthiness of nodes in the consensus process is determined by node trust evaluation,the reputation value is used as the basis for the consensus enthusiasm of rational nodes,consensus nodes are divided based on reputation value,and the consensus method of node network fragmentation is adopted to improve consensus efficiency;secondly,the evolutionary game model is established for the impact of link dynamics between nodes in the consensus process on the reputation value,and based on the existence of the reputation stabilization strategy,an incentive mechanism based on reputation value rewards is designed to enhance the enthusiasm of consensus nodes to participate in consensus.Simulation results show that the consensus algorithm has a throughput increase of 40%,and the reputation evolution game model designed for nodes has a rapid convergence effect in the consensus process.

High energy ball milling and spark plasma sintering(SPS) were used to make high density pure W bulk, the relative density of samples can reach more than 97.0%. TZM alloy powder was laid on the surface of the W bulk, SPS was used to sinter TZM and join W with TZM at the same time. This experiment realized the joining between W bulk and TZM powder without interlayer. The effects of sintering temperature and cooling rate on the microstructure and mechanical properties of W/TZM alloy joints were investigated.The results show that W is well joined with TZM alloy, and there are no holes, microcracks and unwelded defects in the interface. When the sintering temperature is within the scope of 1400-1600℃, W/TZM joints shear strength increases with the increase of sintering temperature. The shear strength of the joints obtained by rapid cooling is higher than that of the joints with slow cooling at the same sintering temperature. When the sintering temperature is 1600℃ and taken rapid cooling, the shear strength of joint is higher than that of the other samples, the maximum shear strength is 159.7 MPa.

High energy ball milling and spark plasma sintering(SPS) were used to make high density pure W bulk, the relative density of samples can reach more than 97.0%. TZM alloy powder was laid on the surface of the W bulk, SPS was used to sinter TZM and join W with TZM at the same time. This experiment realized the joining between W bulk and TZM powder without interlayer. The effects of sintering temperature and cooling rate on the microstructure and mechanical properties of W/TZM alloy joints were investigated.The results show that W is well joined with TZM alloy, and there are no holes, microcracks and unwelded defects in the interface. When the sintering temperature is within the scope of 1400-1600℃, W/TZM joints shear strength increases with the increase of sintering temperature. The shear strength of the joints obtained by rapid cooling is higher than that of the joints with slow cooling at the same sintering temperature. When the sintering temperature is 1600℃ and taken rapid cooling, the shear strength of joint is higher than that of the other samples, the maximum shear strength is 159.7 MPa.

The data reported in this article are structural and physicochemical properties for bare and F, O, OH and CH3O-functionalized Nbn+1Cn (n = 1, 2, 3 and 4) MXenes. The structural properties are presented as top views and side views from the X direction of the optimal structures of studied MXenes. The physicochemical properties include quantum capacitances, electrostatic potentials and electronic properties such as the projected density of states (PDOS) and band structures. Further interpretation and discussion of these data can be obtained from the article entitled âPossibility of bare and functionalized niobium carbide MXenes for electrode materials of supercapacitors and field emittersâ (Xin and Yu, 2017) [1].

Abstract Single-walled carbon nanotubes (SWCNTs) offer great potential for field-effect transistors and integrated circuit applications due to their extraordinary electrical properties. To date, as-made SWCNT transistors are usually p-type in air, and it still remains challenging for realizing n-type devices. Herein, we present efficient and reversible electron doping of semiconductor-enriched single-walled carbon nanotubes (s-SWCNTs) by firstly utilizing decamethylcobaltocene (DMC) deposited by a simple spin-coating process at room temperature as an electron donor. A n-type transistor behavior with high on current, large I on /I off ratio and excellent uniformity is obtained by surface charge transfer from the electron donor DMC to acceptor s-SWCNTs, which is further corroborated by the Raman spectra and the ab initio simulation results. The DMC dopant molecules could be reversibly removed by immersion in N, N-Dimethylformamide solvent, indicating its reversibility and providing another way to control the carrier concentration effectively as well as selective removal of surface dopants on demand. Furthermore, the n-type behaviors including threshold voltage, on current, field-effect mobility, contact resistances, etc. are well controllable by adjusting the surface doping concentration. This work paves the way to explore and obtain high-performance n-type nanotubes for future complementary CMOS circuit and system applications.