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The research progress in thermal aging resistant silicone rubber based heat-proof materials in recent years was reviewed with 46 references. The inorganic modification effects of nano-carbon materials, graphite powder, talc powder, transition metal oxides and fiber fillers on the thermal aging resistance and mechanical properties of silicone rubber based heat-proof materials were emphatically introduced, and the main research directions of thermal aging resistant silicone rubber based heat-proof materials in the future were pointed out.

Lithium metal batteries offer a huge opportunity to develop energy storage systems with high energy density and high discharge platforms. However, the battery is prone to thermal runaway and the problem of lithium dendrites accompanied by high energy density and excessive charge and discharge. This study presents an assisted assembly technique (AAT) based on flexible barium titanate (BTO) and poly-(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanofibers for preparation of a battery separator. AAT was used to combine the BTO diaphragms with high thermal stability and the PVDF-HFP diaphragms with good Elasticity and piezoelectricity, and the thermal stability was improved by 200 and 125% increase in battery cycle life compared to PVDF-HFP diaphragms alone. And demonstrated excellent thermal closure performance between 160 and 200 °C. Furthermore, the piezoelectric effect of the composite film prevents the growth of lithium dendrites in the vertical direction, avoiding the trouble of lithium dendrites penetrating the battery separator. Therefore, the two safety guarantee properties of the composite separator greatly enhance the safety and service life of the battery, which allows the application of lithium batteries to be further improved in the application scenario and application scale. [ABSTRACT FROM AUTHOR]

Piezoelectric catalysis is a way of renewable energy conversion, which involves the application of an external mechanical force to a piezoelectric catalyst. In this work, piezoelectric NiFe2O4 nanofibers with surface oxygen vacancies were successfully synthesized by electrospinning and annealing processes. The introduction of surface oxygen vacancies in NiFe2O4 nanofibers can effectively increase the piezo-catalytic degradation rates by 75% for organic dyes and increase the piezoelectric catalytic hydrogen peroxide generation by 39% in pure water. The piezoelectric catalytic mechanism has been discussed. The oxygen defects enhanced the charge transfer rate and the activation of molecular oxygen, providing more reaction sites for the catalytic process. It was confirmed that superoxide radicals (•O2–) played an important role in the whole catalytic process since force-generated electrons (e–) and holes (h+) migrated to the nanofiber surface and redox reactions occurred under the action of the internal electric field. This work provides a piezoelectric catalyst to achieve efficient degradation of dyes and produce hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Objective To explore the relationship between MRI types and epilepsy control following tumor removal of dysembryoplastic neuroepithelial tumor (DNT). Methods The clinical and follow-up data of DNT cases were retrospectively collected from January 2012 to July 2019, and the data were further analyzed with respect to prognostic factors. Results Epilepsy occurred in all cases. According to MRI-based classification, 8 patients belonged to type I, 4 patients were type II, and the other 2 patients were type III. Tumor total removal was performed in all cases. Postoperative pathological HE staining confirmed each tumor simple contained specific neuronal components in all cases, and in 13 cases, synaptin (Syn), oligodendrocyte transcription factor 2 (Olig-2) and neuronal nuclear antigen (NeuN) were positive in routine immunohistochemical staining. In the postoperative follow-up period from 6-84 months, Engel I outcome was achieved in all type I cases and 2 type II cases, Engel III was in 2 type II cases, Engel II was in 2 type III cases. Conclusions Postoperative seizure control in PNT may be closely associated with the MRI types, and type I may have a better prognosis in seizure control following tumor removal than type II and type III. [ABSTRACT FROM AUTHOR]

Normally, only noncentrosymmetric structure of the materials can potentially be piezoelectric. Thus, it is limited in the field of piezoelectricity for the centrosymmetric structure of the material. In this work, the performance of piezoelectricity is successfully achieved from centrosymmetric SrFeO 3- x by modulating oxygen vacancies, which have a surface piezoelectric potential up to 93 mV by using Kelvin-probe force microscopy (KPFM). Moreover, the piezoelectric effects of SrFeO 3- x are also evaluated by piezoelectric catalytic effect and density functional theory calculations (DFT). The results show that the piezo-catalytic degradation of tetracycline reaches 96% after 75 min by ultrasonic mechanical vibration and the production of H 2 O 2 by SrFeO 3- x piezoelectric synthesis could reach 1821 µmol L -1 . In addition, the DFT results indicate that the intrinsic effect of oxygen vacancies effectively promotes the adsorption and activation of O 2 and H 2 O as well as intermediates and improves the piezoelectric catalytic activity. This work provides an effective basis for realizing the piezoelectricity of centrosymmetric materials and regulating the development of piezoelectric catalytic properties., (© 2023 Wiley‐VCH GmbH.)

Traditional SrTiO 3 (STO) materials have high brittleness and poor deformation resistance. In this work, macroscopically flexible iron-doped SrTiO 3 (SFTO) nanofibrous membranes were prepared by electrospinning and calcination, which can be easily isolated and can maintain integrity to recycle as photocatalysts. Moreover, the SFTO nanofibrous membranes showed enhanced photocatalytic performance under strong acids (pH = 2) and strong alkalis (pH = 12). The SFTO nanofibrous membranes increased the catalytic rate of Congo red (CR) dye by about 10 times in visible light. The mechanism of photocatalytic activity enhancement was discussed by the combined effects of hydroxyl radicals and superoxide radicals. The successful preparation of SFTO nanofibrous membranes has offered a simple and economical approach to photocatalysis as well as environmental remediation.

Immune thrombocytopenia (ITP) is a common acquired autoimmune hematological disorders. Platelet autoantibodies lead to the decrease of platelet production and (or) increase of its destruction. The latest researches showed that the abnormal tryptophan metabolism mediated by indoleamine-2, 3-dioxygenase(IDO) is related with the pathogenesis of ITP. The patients with ITP show less expression of IDO, reduction of Treg cells and increase of autoreactive T cells and autoantibodies. CTLA-4-Ig can improve the expression of IDO in the patients with ITP, which also can inhibit the proliferation and activation of self-reactive T cells. Thus, clarifying the abnormal tryptophan metabolism mediated by IDO may provide a new idea for improving the understand of the pathogenesis and treatment of ITP. This review focuses on reasearch progress of the tryptophan metabolism mediated by IDO and ITP.

Objective: To investigate the therapeutic effect of vascular endothelial growth factor (VEGF) gene expression mediated by recombinant AAV1 (rAAV1) vector in brain ischemia and the mechanism thereof., Methods: Sixty-four SD rats were randomly divided into 2 equal groups and received intra-ventricular injection with rAAV1-VEGF or rAAV1-lacZ as controls. 21 days later the rats underwent transient middle cerebral artery occlusion (MCAO). Neurological severity score (NSS) was recorded 1, 2, 3, 7, 14, and 21 days after MCAO. 48 rats were sacrificed 21 days after MCAO and brains were taken out from 48 rats. Immune quantitative analysis was used to identify the quantity of VEGF expression. Immunohistochemistry was used to identify the site of VEGF expression. Immunofluorescence double labeling of von Willebrand factor (vWF) and 5-bromodeoxy-uridine (BrdU) was performed to detect the proliferation of endothelial cells. Fluorescein isothiocyanate (FITC)-dextran was infused into the caudal vein of 8 rats from each group and then the rats were killed with their brains taken out to evaluate the cerebral microvessel perfusion and microvessel density., Results: The NSSs of the VEGF group 7, 14, and 21 days after MCAO were all significantly lower than those of the control group (all P < 0.05), and the VEGF165 protein expression quantity was 27 times as that of the control group (P < 0.05). Immunohistochemistry demonstrated that VEGF expression was distributed mainly in the caudate putamen, corpus callosum, choroid plexus, and hippocampus in the VEGF group, while no expression was detected in the control group. The microvessel density of the VEGF group was 157 +/- 13, significantly higher than that of the control group [(89 +/- 9), P < 0.05]. BrdU +/vWF + endothelial cells were detected in the area adjacent to the MCAO. The density of microvessel infused with FITC-dextran was (152,617 +/- 13,076) microm2/mm2 in the VEGF group, significantly higher than that of the control group [(91,658 +/- 6577) microm2/mm2 P < 0.05]., Conclusion: rAAV1 mediates the VEGF gene expression in multiple structures in the brain and attenuates the neurological deficit of MCAO. VEGF gene transfer may stimulate angiogenesis and improves blood supply in brain. Neovascularization may be a therapeutic strategy for brain ischemia.

Objective: To investigate the effects of treatment of stroke in rats with bone marrow mesenchymal stem cells (BMSCs) and mechanism thereof., Methods: Bone marrow of a healthy volunteer was collected and the BMSCs were separated with density gradient centrifugation. The hBMSC were cultivated and harvested until the third passage. A number of adult male Sprague-Dawley rats received corresponding behavioral training before surgery and underwent transient middle cerebral arterial occlusion (MCAO) for 2 hours. Sixty of them showing the scores of 6 approximately 12 according to the modified neurological severity score system were randomly divided into 2 groups: treatment group (n = 48, injected into the cortex around the ischemic areas with hBMSCs 3x10(5)/15 microl) and control group (n = 12, injected with D-Hanks solution 15 microl 24 hours after the establishment of MCAO models. Morris water maze test, Rotarod test and adhesive-removal test were performed since the 4th day to the 32 day after transplantation once every 3 days. 1, 2, 3, and 4 weeks after the transplantation 12 rats from each group were killed randomly to take out their brains. Immunofluorescence was used to identify the migration, survival and differentiation of the hBMSC., Results: A large number of hBMSC could be seen within 2 weeks after transplantation. The number of hBMSC decreased since the 21st day after transplantation and few cells could be found at the end of 1 month after. No definite evidence supported the differentiation of neural cells derived from the hBMSCs during the whole process. Morris water maze test showed that the mean escape time 1 week after transplantation of the treatment group was (69 +/- 10) s, significantly shorter than that of the control group [(120 +/- 0) s, P < 0.05] The significant difference persisted until the 4(th) week (P > 0.05). Rotarod test with the speed of 10 r/min showed that the mean latency period 10 days after transplantation of the treatment group was (167 +/- 18) s, significantly longer than that of the control group [(37 +/- 19) s, P < 0.05]. The significant difference persisted until the experimental terminal. The adhesive-removal test showed that the mean latency period 13 days after transplantation of the treatment group was (33 +/- 8) s, significant shorter than that of the control group [(84 +/- 13) s, P < 0.05]. The significant difference persisted until the experimental terminal., Conclusion: Injection of hBMSCs into brain cortex improves neurological functional recovery after stroke. The transplanted cells can migrate and survive for a certain period, but no hBMSC express proteins phenotype of neural cells.

Objective: To explore the gene transfer efficiencies and different cell tropism of recombinant adeno-associated virus 1 (rAAV1), rAAV 2, and rAAV 5 in the hippocampus of adult rats, and select more suitable gene vectors for central nervous system (CNS) gene therapy., Methods: Eighteen SD male adult rat were divided into 3 groups randomly (n = 6), with every group being injected with the titre and volume matched rAAV1, rAAV2, and rAAV5 vectors. All these vectors contained enhanced green fluorescent protein (EGFP) sequences as a reporter gene. Animals were killed after 8 weeks. The coronal cryosections of brains were processed, and the EGFP gene expression was observed with fluorescence microscopy; the expression area and the number of EGFP positive cells were automatically measured using Image-Pro Plus 4.5 software. To identify their cell tropism in the CNS, the sections were counterstained with neuronal marker neuron-specific nuclear protein (NeuN) and the astrocyte marker glial fibrillary acidic protein (GFAP) and were examined with a confocal laser scanning microscope., Results: Eight weeks after adeno-associated virus gene transfer, the expression profile of EGFP demonstrated significant difference. Most of the pyramidal cell layers of CA1 to CA3 area and granular cell of dent gyrus were strongly transduced by rAAV1; whereas rAAV2 primarily transduced the cells of multiform layer in hilar region of the dentate gyrus; only a few pyramidal cells were transduced by rAAV5. Moreover, rAAV1 showed significantly wider distribution throughout the hippocampus, and the quantity of EGFP positive cells and the EGFP positive area were significantly more than those of rAAV2 and rAAV5 (P < 0.01). The counterstaining for NeuN and GFAP showed that rAAV1 was able to transduce both neurons and glia cells, whereas rAAV2 and rAAV5 transduced the neurons only., Conclusion: rAAV1 is an excellent transgene vector with higher efficiency and broader cell tropism in the CNS.