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1.
Osteogenic glue that reproduces the natural bone composition represents the final frontier of orthopedic adhesives with the potential to revolutionize surgical strategies against comminuted fractures. However, it is difficult to achieve an all-in-one formula, which could provide flexible and reliable adhesiveness while avoiding interfering with or even promoting the healing of glued fractures. Herein, an osteogenic glue characterized by inorganic-in-organic integration between amine-modified mesoporous bioactive glass nanoparticles (AMBGN) and bioadhesive gelatin-dextran network (GelDex) is introduced as an all-in-one tool to flexibly adhere and splice bone fragments and subsequently guide fracture healing during degradation. Relying on such integration, a 4-fold improvement in cohesiveness is presented, followed by a nearly 5-fold enhancement in adhesive strength in ex vivo porcine bone samples. The reversible and re-adjustable adhesiveness also enables glue to effectively splice intricate fragments from highly comminuted fractures in the rabbit radius in an in vivo environment. Moreover, well-preserved organic–inorganic integrity during degradation of the glue guides sustained interfacial osteogenesis and achieve satisfying healing outcomes in glued fractures, as observed by the 2-fold improvement in biomechanical and radiological performance compared with commercially available cyanoacrylate adhesives. The current findings propose an all-in-one solution for the fixation of bone fragments during surgery.  相似文献   
2.
To solve the potential supply disruption in cruise-building supply chain, this study explores a supply system consisting of a monopoly supplier, a new entrant supplier, and a cruise-building manufacturer. A two-step option contract including diagnostic test and process improvement is designed to solve the order quantity allocation and to avoid supply disruption. The analysis combines the decision tree with the principal-agent model under information asymmetry. The result shows that the cruise-building manufacturer would like to allocate more orders to the unreliable supplier who implements process improvement. In the end, the detailed numerical analysis is implemented to justify the proposal.  相似文献   
3.
To minimize the cytotoxicity of shikonin and alkannin that arises through the generation of reactive oxygen species (ROS) and alkylation of the naphthazarin ring, two series of novel core‐scaffold‐modified shikonin and alkannin derivatives were designed. These derivatives, which differ in their configurational and positional isomerism (R‐, S‐, and 2‐ and 6‐isomers) were synthesized in high enantiomeric excess (>99 % ee). The selectivity of the dimethylated derivatives was significantly higher than the parent shikonin in vitro, but some side effects were still observed in vivo. Surprisingly, the dimethylated diacetyl derivatives with poor anticancer activity in vitro showed tumor‐inhibiting effects similar to paclitaxel without any toxicity in vivo. The anticancer activity of these derivatives is in agreement with their low ROS generation and alkylating capacity, emphasizing their potential as prodrugs. This strategy provides means to address the nonspecific cytotoxicity of naphthazarin analogues toward normal cells.  相似文献   
4.
A cheap and commercially available small molecule (namely EPPDI) is introduced to the active layer of N2200-based all polymer solar cells as a solid additive. EPPDI at the optimal ratio can improve the D-A nano-scale morphology and reduce trap density of the active layer by filling morphological spaces. As a result, the photovoltaic performance of the resulting devices based on PF2:N2200 are increased from 6.28% to 7.03% with significantly enhanced fill factor. This work demonstrates a facile approach for improving the performance of all polymer solar cells.  相似文献   
5.
【摘要】 目的 探讨慢性肾病是否为冠状动脉慢性完全闭塞病变(CTO)侧支循环形成不良的独立预测因素。 方法 2003年1月至2011年10月收治125例经冠状动脉造影确诊为CTO患者。运用Rentrop评分系统将患者分为有侧支循环组(99例)和无侧支循环组(26例);并用多因素Logistic回归分析校正混杂因素。结果 多因素Logistic回归分析表明,慢性肾病是CTO侧支循环形成不良的独立预测因素(OR = 5.22, P = 0.021)。结论 合并慢性肾病的CTO患者冠状动脉侧支循环形成不良的相对危险是不合并慢性肾病患者的5.22倍。

  相似文献   
6.
This research has investigated physical variables affecting indoor thermal comfort and subjective responses of thermal comfort of students in a university in Korea in which the weather is oceanic temperate climate, and has been performed to contribute to the research fields of Sustainable Thermal Standard and Adaptive Thermal Comfort (ATC). This research is based on the ISO 7730-2005 standard and the ATC theories and 4 main variables of PMV such as dry bulb temperature (Ta), relative humidity (RH), black bulb temperature (Tg), and air velocity (Va) are measured once a week during two regular semesters. A clothing insulation, a thermal sensation vote (TSV), an acceptability of thermal environment, and a preference for cooling and heating are investigated at the same time using a questionnaire. This study was carried out for 26 weeks during the spring season, from March to June 2009, and the autumn season, from September to December 2009. The main achievements of this study are as follows. Monthly Mean Outdoor Temperature (MMOT) and Operative Temperature (OT) in the classroom during research periods are 7.4∼23.3°C and 17.5∼29.0°C, respectively. The acceptability ratio of thermal environment shows over 80% when the range of OT in the classroom is 17∼25°C, and the range can be applicable to operative index of heating and cooling of classroom. The mean TSV of respondents is almost “neutral (0)” when the PMV in the classroom moves to “neutral (0)” and “slightly cool (−1)”, and the TSV is almost “+1.5” when the PMV moves to “slightly warm (+1)”. The acceptability ratio of thermal environment is slightly different from ASHRAE Standard 55-2004. So it is necessary to more investigate standard range of acceptability of thermal environment in oceanic temperate climate region using much more databases.  相似文献   
7.
8.
李超群  包海龙  杜科  陆敏珏 《供用电》2011,28(4):41-44,49
根据上海电网的实际情况和运行管理的特殊要求,进行上海电网继电保护标准化设计的研究,可作为对国家电网公司有关变电站继电保护及二次系统典型设计的贯彻落实和补充。介绍了上海电网220 kV线路保护标准化设计的背景,对照国家电网公司的有关规定,阐述了上海电网220 kV线路保护标准化设计的配置原则、组屏方案及设计要点。着重分析了标准化设计实施过程中存在的主要问题,并提出了解决问题的建议。  相似文献   
9.
阐述了电力电池储能系统规模化的集成技术和接入技术的研究和应用现状。分析了我国电力电池储能系统存在的主要问题,从需求、技术和经济的角度出发,指出了我国储能产业的发展前景,提出了促进大容量储能产业发展的政策建议。  相似文献   
10.
分析某220 kV变电站的周边环境对工程的影响因素以及变电站的工程概况,提出从深基坑设计角度对周边环境进行保护的2个技术措施,并指出效果。  相似文献   
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