Injectable hybrid inorganic nanoscaffold as rapid stem cell assembly template for cartilage repair

Cartilage injuries are often devastating and most cannot be cured because of the intrinsically low regenerative capacity of cartilage tissues. Although stem-cell therapy has shown enormous potential for cartilage repair, the therapeutic outcome has been restricted by low survival rates and poor chondrocyte differentiation in vivo. Here, we report an injectable hybrid inorganic (IHI) nanoscaffold that facilitates fast assembly, enhances survival and regulates chondrogenic differentiation of stem cells. IHI nanoscaffolds that strongly bind to extracellular matrix (ECM) proteins assemble stem cells through synergistic 3D cell–cell and cell–matrix interactions, creating a favorable physical microenvironment for stem-cell survival and differentiation in vitro and in vivo. Additionally, chondrogenic factors can be loaded into nanoscaffolds with a high capacity, which allows deep, homogenous drug delivery into assembled 3D stem-cell-derived tissues for effective control over the soluble microenvironment of stem cells. The developed IHI nanoscaffolds that assemble with stem cells are injectable. They also scavenge reactive oxygen species and timely biodegrade for proper integration into injured cartilage tissues. Implantation of stem-cell-assembled IHI nanoscaffolds into injured cartilage results in accelerated tissue regeneration and functional recovery. By establishing our IHI nanoscaffold-templated 3D stem-cell assembly method, we provide a promising approach to better overcoming the inhibitory microenvironment associated with cartilage injuries and to advance current stem-cell-based tissue engineering.     

江西移民记忆中的瓦屑坝

这里是废墟,数不清的瓦屑陶片堆起了一条长坝,片片瓦砾散落在绿杨衰草之间,流水泥沙之中。昔日的荣华变成了遐想,变成了供人凭吊的沼泽,绿装翠盖的芦苇芰荷遍布其间。几百万江西移民曾经带着诀别,带着失落从这里出发,渡过茫茫大湖,驶向一个未知的远方……     

小学道德与法治课程校本化实施的基本路径

道德与法治课程要落实立德树人的根本任务,发挥"道德情感启蒙"的教育作用,在拥有《课程标准》、系列文件和"文化母乳"般教材基础上,只有引导学校、教师找到校本化实施的基本路径,才能真正发挥其在课程体系中的政治引领和价值引领作用。这个路径就是以把握课标、吃透教材为基础,以基于学情、深化目标为灵魂,以"新鲜"事件为拓展资源,以便于操作的教学模式为关键,以提升品位、知行合一为策略。     

"十一五"期间我国高职教育规模发展途径及应注意的问题

“十一五”期间,我国高职教育的规模仍将不断发展。强化特色,进一步落实办学自主权,划转部分第三层次的普通高校举办高职教育等是高等职业教育规模发展的重要途径。在高职教育规模发展过程中还要注意规模与质量、就业之间的关系,注意合理构建高职教育的层次结构,完善高职教育的专业布局,实现高职和中职的有效衔接。     

地区法律保护与企业创新

基于各地区市场中介组织的发育和法律制度环境指数,以及手工搜集的各上市公司专利数据,利用Tobit回归模型,考察法律保护对企业创新的影响。研究发现:知识产权保护、市场组织服务条件显著地促进了企业创新,说明法律保护为企业创新活动提供了激励;对国有企业而言,律师、会计师等市场组织服务条件对于企业创新活动的影响不明显,表明国有企业在市场组织服务方面占有资源优势从而较少受到其约束;在社会信任程度低的地区,企业创新对法律保护的依赖程度更高,这反映了社会资本不足时,正式制度对市场发展的重要作用。     

基于车辆自动定位系统数据的地面公共交通运行时间可靠性分析(英文)

为了给公交线路车辆调度提供重要参数及给公交运营管理和居民公交出行提供决策依据,应用车辆自动定位系统数据对公共交通运行时间可靠性进行了分析. 基于对公共交通运行时间的统计分析,提出变异系数、分布宽度、运行速度、堵率、规划时间、预留时间等 6 个指标,构建了公共交通运行时间可靠性评价分析框架. 苏州市某公交线路实例分析结果表明,所提出的评价指标体系简单直观,能有效反映该线路公交车辆运行的效率和稳定性,且公共交通运行时间可靠性具有随不同时段变化的特征.     

中国体育价值选择的历史演变及展望

本文对体育价值选择的内涵及特征进行了阐述,将中国体育的历史进程分为6个阶段,并分析了每个阶段不同的体育价值选择,最后对中国未来的体育价值选择作出了展望,希望能为体育的可持续发展提供理论参考.     

职高学生参加体育活动兴趣的调查与分析

运用文献、调查和对比等多种研究方法,对平阳县职业技术学校520名学生参加体育活动兴趣进行调查分析,针对学生参加体育兴趣不高的原因,提出相应的对策与措施,以增强学生的体育意识,提高体育健身的能力,养成体育锻炼的习惯,达到终身受益的目的。     

区域一体化对城市创新能力驱动研究——基于长三角的实证分析

长三角更高质量一体化发展标志着各种资源要素在长三角区域内的配置效率将进一步提升,有利于形成更强的区域创新能力。本文基于2005—2017年长三角城市统计数据,考察了区域一体化对城市创新能力的驱动作用,并对其中的影响机制和异质性进行了深入分析。结果显示：(1)区域一体化对长三角城市创新能力具有显著的促进作用。(2)机制分析发现,一体化伴随的产业集聚并未形成创新能力提升机制,但一体化推动的区域内部产业转移机制有效提升了城市创新能力。(3)异质性分析表明,长三角区域一体化对非核心城市、欠发达城市、低财政分权城市具有更为显著的城市创新能力驱动作用。     

Water molecules bonded to the carboxylate groups at the inorganic–organic interface of an inorganic nanocrystal coated with alkanoate ligands

High-quality colloidal nanocrystals are commonly synthesized in hydrocarbon solvents with alkanoates as the most common organic ligand. Water molecules with an approximately equal number of surface alkanoate ligands are identified at the inorganic–organic interface for all types of colloidal nanocrystals studied, and investigated quantitatively using CdSe nanocrystals as the model system. Carboxylate ligands are coordinated to the surface metal ions and the first monolayer of water molecules is found to bond to the carboxylate groups of alkanoate ligands through hydrogen bonds. Additional monolayer(s) of water molecules can further be adsorbed through hydrogen bonds to the first monolayer of water molecules. The nearly ideal environment for hydrogen bonding at the inorganic–organic interface of alkanoate-coated nanocrystals helps to rapidly and stably enrich the interface-bonded water molecules, most of which are difficult to remove through vacuum treatment, thermal annealing and chemical drying. The water-enriched structure of the inorganic–organic interface of high-quality colloidal nanocrystals must be taken into account in order to understand the synthesis, processing and properties of these novel materials.