Comparative Study of LiMn2O4 Thin Films Heat-treated by Conventional and Rapid Thermal Annealing

Cathode material LiMn2O4 thin films were prepared by solution deposition followed by conventional thermal annealing （CTA） and rapid thermal annealing （RTA） using lithium acetate and manganese acetate as starting materials. The phase and surface morphology identification was done by X-ray diffraction and scanning electron microscopy. The electrochemical properties of the thin films were carried out by cyclic voltammetry, chargedischarge experiments, electrochemical impedance spectroscopy and potential step technique. The results show that both thin films are homogeneous and crack-free. Compared with the CTA derived thin films, the RTA derived ones with smaller grain size are more smooth and dense. The CTA and RTA derived LiMn2O4 thin films deliver the capacity of 34.5μAh/（cm^2·μm） and 38μAh/（cm^2·μm） ） and show the capacity loss of 0.050% and 0.037% per cycle after being cycled 100 times, respectively. The diffusion coefficient of lithium ion in the CTA derived LiMn2O4 thin-film electrode is 4.59×10^-11cm^2/s, and that of lithium ion in the RTA derived one is 3.86×10^-11cm^2/s.

Theoretical Study of Agricultural High-tech Industrialization

This paper introduces the characteristics of the agricultural high-tech industries,and points out that the agricultural high-tech industries are intelligence-intensive and knowledge-intensive industries with the characteristics of high investment,high risk,high value-added, which focuses on constant innovation,having strong horizontal and vertical linkages with other enterprises and showing the trend of internationalization.The connotation of agricultural high-tech industrialization is analyzed as follows:Agricultural high-tech industrialization is the process of transformation of the agricultural high-tech achievements to the agricultural high-tech industries; essentially the marketization and commercialization of agricultural high technology; the manifestation of scale and level of agricultural high-tech industries; the manifestation of social impact,social status and social role of agricultural high-tech industries.The development strategies are put forward for agricultural high-tech industrialization:(1) Bringing the research of agricultural high technology into the orbit of the market economy; (2) Implementing the new mechanism to closely link agricultural high technology with modern rural enterprises; (3) Building the agricultural high-tech team with a larger size and high level; (4) Further improving the construction of the agricultural high-tech industrial development zone; (5) Solving the issues concerning agricultural intellectual property and patent; (6) Increasing policy guidance and support efforts for agricultural high-tech industries.

Transplantation of neural stem progenitor cells from different sources for severe spinal cord injury repair in rat

Neural stem progenitor cell(NSPC)transplantation has been regarded as a promising therapeutic method for spinal cord injury(SCI)repair.However,different NSPCs may have different therapeutic effects,and it is therefore important to identify the optimal NSPC type.In our study,we compared the transcriptomes of human fetal brain-derived NSPCs(BNSPCs),spinal cord-derived NSPCs(SCNSPCs)and H9 embryonic stem-cell derived NSPCs(H9-NSPCs)in vitro and subsequently we transplanted each NSPC type on a collagen scaffold into a T8-9 complete SCI rat model in vivo.In vitro data showed that SCNSPCs had more highly expressed genes involved in nerve-related functions than the other two cell types.In vivo,compared with BNSPCs and H9-NSPCs,SCNSPCs exhibited the best therapeutic effects;in fact,SCNSPCs facilitated electrophysiological and hindlimb functional recovery.This study demonstrates that SCNSPCs may be an appropriate candidate cell type for SCI repair,which is of great clinical significance.

Lineage tracing reveals the origin of Nestin-positive cells are heterogeneous and rarely from ependymal cells after spinal cord injury

Nestin is expressed extensively in neural stem/progenitor cells during neural development, but its expression is mainly restricted to the ependymal cells in the adult spinal cord. After spinal cord injury(SCI), Nestin expression is reactivated and Nestinpositive(Nestin;) cells aggregate at the injury site. However, the derivation of Nestin;cells is not clearly defined. Here, we found that Nestin expression was substantially increased in the lesion edge and lesion core after SCI. Using a tamoxifen inducible CreER(T2)-loxP system, we verified that ependymal cells contribute few Nestin;cells either to the lesion core or the lesion edge after SCI. In the lesion edge, GFAP+astrocytes were the main cell type that expressed Nestin;they then formed an astrocyte scar.In the lesion core, Nestin;cells expressed αSMA or Desmin, indicating that they might be derived from pericytes. Our results reveal that Nestin;cells in the lesion core and edge came from various cell types and rarely from ependymal cells after complete transected SCI, which may provide new insights into SCI repair.

Single-cell RNA sequencing reveals Nestin+active neural stem cells outside the central canal after spinal cord injury

Neural stem cells(NSCs)in the spinal cord hold great potential for repair after spinal cord injury(SCI).The ependyma in the central canal(CC)region has been considered as the NSCs source in the spinal cord.However,the ependyma function as NSCs after SCI is still under debate.We used Nestin as a marker to isolate potential NSCs and their immediate progeny,and characterized the cells before and after SCI by single-cell RNA-sequencing(scRNA-seq).We identified two subgroups of NSCs:the subgroup located within the CC cannot prime to active NSCs after SCI,while the subgroup located outside the CC were activated and exhibited the active NSCs properties after SCI.We demonstrated the comprehensive dynamic transcriptome of NSCs from quiescent to active NSCs after SCI.This study reveals that Nestin+cells outside CC were NSCs that activated upon SCI and may thus serve as endogenous NSCs for regenerative treatment of SCI in the future.