Compensatory recombination phenomena of neurological functions in central dysphagia patients

We speculate that cortical reactions evoked by swallowing activity may be abnormal in patients with central infarction with dysphagia. The present study aimed to detect functional imaging features of cerebral cortex in central dysphagia patients by using blood oxygen level-depen- dent functional magnetic resonance imaging techniques. The results showed that when normal controls swallowed, primary motor cortex （BA4）, insula （BA13）, premotor cortex （BA6/8）, supramarginal gyrus （BA40）, and anterior cingulate cortex （BA24/32） were activated, and that the size of the activated areas were larger in the left hemisphere compared with the right. In re- current cerebral infarction patients with central dysphagia, BA4, BA13, BA40 aild BA6/8 areas were activated, while the degree of activation in BA24/32 was decreased. Additionally, more areas were activated, including posterior cingulate cortex （BA23/31）, visual association cortex （BA18/19）, primary auditory cortex （BA41） and parahippocampal cortex （BA36）. Somatosen- sory association cortex （BA7） and left cerebellum in patients with recurrent cerebral infarction with central dysphagia were also activated. Experimental findings suggest that the cerebral cortex has obvious hemisphere lateralization in response to swallowing, and patients with recurrent cerebral infarction with central dysphagia show compensatory recombination phenomena of neurological functions. In rehabilitative treatment, using the favorite food of patients can stimu- late swallowing through visual, auditory, and other nerve conduction pathways, thus promoting compensatory recombination of the central cortex functions.

Electrolytic production of Ti-Ge intermetallics from oxides in molten CaCl_2-NaCl

Titanium germanium intermetallics （TixGey）were directly prepared from titanium oxide （TiO2） and germanium oxide（GeO2） powders mixture by using an electrodeoxidation process. The electrochemical experiment was carried out in a molten fluxCaCl2-NaCl at 800℃ with a potential of 3.0 V. The results show that monolithic germanide Ti5Ge3 intermetallic can be directlyproduced from TiO2-GeO2 or CaTiO3-GeO2 precursors （both molar ratios are 5：3）, and the obtained Ti5Ge3 powders exhibithomogenous particle structure. In addition, the phase composition of the final product can be dramatically affected by the initialmolar ratio of TiO2 to GeO2. The reaction mechanism of the electrodeoxidation process was discussed based on the experimentalresults. It is suggested that the electrodeoxidation process is an environmentally friendly method for the preparation of Ti-Geintermetallics.

Molten salt electrosynthesis of silicon carbide nanoparticles and their photoluminescence property

A one-step molten salt electrochemical strategy was proposed to synthesize SiC nanoparticles from ultra-fine silicon dioxide/carbon(SiO_(2)/C)mixtures.The electrosynthesis process and physicochemical properties of the synthesized products were systematically analyzed via X-ray diffraction,electron microscopy,Raman spectroscopy and photoluminescence spectroscopy,etc.A combined chemical/electrochemical reaction,electrochemical deoxidation,and in-situ carbonization reaction mechanism was proposed to reveal the electrochemical synthesis process of SiC nanoparticles from SiO_(2)/C in molten CaCl_(2).The as-prepared SiC with particle size ranging from 8 to 14 nm possesses a polycrystalline structure.In addition,the SiC nanoparticles demonstrate obvious photoluminescence property due to the synergetic size effect and microstructural characteristics.

Room-temperature Self-healing and Recyclable PDMS Elastomers with Superior Mechanical Properties for Triboelectric Nanogenerators

Polydimethylsiloxane(PDMS)is an electron-withdrawing material that is widely used in triboelectric nanogenerators(TENGs).However,PDMS has poor mechanical properties after curing and is easily damaged when subjected to long-term workloads.Thus,the long-term stable operation of TENGs under mechanical deformation cannot be guaranteed.In this work,multiple hydrogen bonds and aromatic disulfide bonds were introduced into PDMS elastomers.These elastomers exhibited high toughness(a tensile strength of 1.91 MPa and an elongation at break of 340%),good recyclability,and room-temperature self-healing properties(healing efficiency of 96.4%in 24 h).Recyclable sandwich-like triboelectric nanogenerators with excellent electrical output performance(13.5 V)and room-temperature self-healing performance(24 h,98%recovery of self-generating performance)were prepared by utilizing the hydrogen bonding between the PDMS elastomer and MXene.The work reported herein offers theoretical guidance and a compelling strategy for developing high-performance TENG negative friction layers.

动态共价键高分子材料的研究进展

动态共价键在外界刺激(光、热、力、pH)作用下处于可逆的断裂和重新形成的平衡,与传统热固性树脂相比,动态共价键交联的高分子材料(Vitrimer或类玻璃高分子)的分子拓扑结构可动态调整,重排,且其结构构筑和性能研究对于高分子材料的加工成型、循环回收以及自愈合具有重要意义.本文以可逆共价键反应为线索,整理分析了动态共价键的类型及其动态影响因素,对多种动态共价键在高分子材料设计和构建中的应用做出评述,并对动态共价键高分子材料的未来发展作了展望.

Bone Metabolic Markers in Patients with Obstructive Sleep Apnea Syndrome

Background： Obstructive sleep apnea syndrome （OSAS） is prevalent in obesity and is associated with many metabolic abnormalities. The relationship between OSAS and bone metabolism is still unclear. The aim of this study was to investigate the relationship between the severity of OSAS and bone metabolic markers. Methods： A total of 119 obese males were enrolled in this study in spring months from 2015 to 2017. All candidates underwent polysomnography, and their bone mineral density （BMD） and the serum levels of total procollagen type 1 N-tenninal propeptide （t-P I NP）, N-terminal midfragment ofosteocalcin （N-MID）, [3-C-terminal telopeptide of type 1 collagen （β-CTX）, vitamin D （VD）, and parathyroid hormone （PTH） were measured. The analysis of variance and Pearson correlation analysis were performed for data analyses. Results： No significant differences in the mean values of BMD were observed among the obesity, mild-to-moderate OSAS, and severe OSAS groups; and the serum levels oft-P1NP and [3-CTX in the severe OSAS group were significantly higher than those in the obesity group （48.42 ±23.78 ng/ml vs. 31.98 ± 9.85 ng/ml, P 〈 0.001 ; 0.53 ± 0.24 ng/ml vs. 0.41 ±0.13 ng/ml, P 0.011, respectively）. The serum level of VD in the obesity group was significantly higher than those in the mild-to-moderate and severe OSAS groups （both P 〈 0.001 ）, and decreased as the severity of OSAS increased （P 〈 0.001）. The serum level of PTH in the severe OSAS group was significantly higher than those in the obesity and mild-to-moderate OSAS groups （both P 〈 0.001 ）. The results of correlation analysis indicated that the level of apnea-hypopnea index （AHI） was correlated with the levels oft-P1NP （r = 0.396, P 〈 0.001 ）, VD （r = 0.404, P 〈 0.001 ）, and PTH （r = 0.400, P 〈 0.001 ）, whereas the level of minimum 02 saturation （SaO2min） was correlated with the levels ofVD （r = 0.258, P=0.016） andPTH（r= 0.376, P〈0.001）. Conclusions： The levels of bone resorption and formation markers in patients with severe OSAS were significantly increased compared to obese men, and the severity of OSAS was correlated with the serum levels of t-P1NP, VD, and PTH.