Preparation and characteristics of moulded biodegradable cellulose fibers/MPU-20 composites (CFMCs) by steam injection technology

In this work, the moulded cellulose fibers/MPU-20 composites (CFMCs) with apparent specific gravity lower than 100 kg/m³ and thickness of 20–200 mm have been successfully manufactured using a new design of steam injection technology and equipment. It was found that the CFMCs have good cushioning properties, with a cushion factor lower than 4. Two yield deformation stages were observed in the compressive process. Compressive stress–strain and cushion factor-stain curves were measured as a function of steam injection pressure, transmission time, holding time, MPU-20 resin dosage and apparent specific gravity. Chemical groups, crystallinity, and thermal properties of samples were studied through the use of FTIR spectroscopy, X-ray diffraction (XRD), and DTA–TGA. In addition, the microstructure and morphology were investigated by scanning electron microscope (SEM) and atomic force microscope (AFM).     

钛合金表面沉积AlTiN涂层的生物摩擦磨损特性研究

采用高度离子化脉冲工艺(H.I.P)在医用钛合金Ti6Al4V表面制备AlTiN涂层;在摩擦磨损试验机上测试了涂层在37℃的模拟人体生理血清液润滑条件下的摩擦磨损性能,并与之和未经涂层的Ti6Al4V合金作比较.结果表明,相同条件下,经沉积AlTiN涂层的试样磨损量仅为基材的1.2%,摩擦系数仅0.007,表现出良好的抗磨损特性;并用SEM、EDS、XRD等,对涂层的生物摩擦磨损性能进行了分析.     

Real‐time monitoring and control of the load phase of a protein A capture step

The load phase in preparative Protein A capture steps is commonly not controlled in real‐time. The load volume is generally based on an offline quantification of the monoclonal antibody (mAb) prior to loading and on a conservative column capacity determined by resin‐life time studies. While this results in a reduced productivity in batch mode, the bottleneck of suitable real‐time analytics has to be overcome in order to enable continuous mAb purification. In this study, Partial Least Squares Regression (PLS) modeling on UV/Vis absorption spectra was applied to quantify mAb in the effluent of a Protein A capture step during the load phase. A PLS model based on several breakthrough curves with variable mAb titers in the HCCF was successfully calibrated. The PLS model predicted the mAb concentrations in the effluent of a validation experiment with a root mean square error (RMSE) of 0.06 mg/mL. The information was applied to automatically terminate the load phase, when a product breakthrough of 1.5 mg/mL was reached. In a second part of the study, the sensitivity of the method was further increased by only considering small mAb concentrations in the calibration and by subtracting an impurity background signal. The resulting PLS model exhibited a RMSE of prediction of 0.01 mg/mL and was successfully applied to terminate the load phase, when a product breakthrough of 0.15 mg/mL was achieved. The proposed method has hence potential for the real‐time monitoring and control of capture steps at large scale production. This might enhance the resin capacity utilization, eliminate time‐consuming offline analytics, and contribute to the realization of continuous processing. Biotechnol. Bioeng. 2017;114: 368–373. © 2016 The Authors. Biotechnology and Bioengineering published by Wiley Periodicals, Inc.     

基于信息技术基础架构库理念的HIS运行维护管理

针对当前医院信息系统运行维护所遇到的问题,结合医院信息技术部门所做的日常工作,总结遇到的问题以及发展瓶颈,利用信息技术基础架构库理念的核心,即将信息技术与业务相结合使其系统化、流程化,研究设计一套基于信息技术基础架构库理念的医院信息网络运行维护管理模式,将维护人员从平日被动的救火模式转换成一个将日常业务、项目管理、服务提供变为自动化、规范化的管理模式,从而实现精细化管理。     

稳定表达GLP-1类似物的CHO细胞株的构建及培养工艺研究

胰高血糖素样肽-1(Glucagon like peptide-1,GLP-1)是一种治疗II型糖尿病的潜在药物,针对其在体内半衰期短和在酵母中表达的批次间不稳定等问题,课题组前期对其进行改造,成功利用p MH3载体在中国仓鼠卵巢(Chinese hamster ovary,CHO)细胞中表达人血清白蛋白(human serum albumin,HSA)融合蛋白NGGH[6×His-tag+Ek+2×GLP-1(A2G)+HSA]。现利用新型载体pcDNA3.1,构建含融合蛋白的真核表达质粒pcDNA3.1/NGGH,经电击转染转入CHO细胞中。G418抗性压力筛选后利用一种新型的细胞成像系统高效快速地筛选出高表达单克隆株。表达的目的蛋白经WB(Western blot)验证显示,产物具有GLP-1和HSA的双抗原性。经悬浮驯化稳定后,通过批次筛选得到一株稳定的高表达细胞株,产量为58mg/L。利用5L AP20激流式生物反应器扩大培养重组细胞,对p H和溶氧控制条件进行了优化。结果显示,在p H6.8~7.4,溶氧(dissolved oxygen,DO)两相控制的条件下,蛋白质最终表达量可达148mg/L。     

L’humanisation au prisme des pierres taillées

Knapped stone tools constitute an interesting evidence of the mental abilities of their makers. Almost imperishable, they bear visible traces of the successive removals they come from, and of the flaking techniques used. On that basis, we present a few remarkable achievements along the evolution of prehistoric lithic technology, and discuss their capabilities. The tools of the oldest Palaeolithic already surpass the nut cracking from Chimpanzees. Some core reductions into flakes, as early as 2.3 My, show a repeated organization of the removals, and the capacity to prevent a problem. The regular and symmetrical hand-axes from Africa and Europe, appearing between 1 and 0.5 My, provide evidence of a mental template and hence a capacity of conceptualization. The Levalloisian core reduction, somewhat more recent, give evidence of a goal structured method: the technical actions were hierarchized and subordinate to morphological intentions.     

基于整合宏组学技术认识腐生生境功能微生物区系

微生物区系在天然生境中分布广泛,利用传统纯培养等方法无法全面认识其分布和功能,因此被认为是地球上的"暗物质"。随着新一代测序技术与高分辨率质谱技术的快速发展,研究者可以在非培养条件下全面快速分析天然生境中微生物组及其动态变化,这开启了微生物组时代,使得研究地球上"暗物质"成为可能,从而改变了微生物学研究的现状。腐生生境作为生物地球化学循环的重要推动部分,因其高效降解转化有机废弃物能力而被广泛关注。腐生生境由于原料多变、环境复杂等原因未能被全面深入研究,而整合宏组学技术则为解析相关生境微生物区系的多样性及其功能动态演替规律奠定了技术基础。基于整合宏组学数据分析与环境参数的优化,可以在认识微生物组及其功能的动态水平上,针对复杂物料建立高效降解转化的绿色转化工艺,促进农牧业废弃物无害化和资源化利用进程。     

Climate trends account for stalled wheat yields in Australia since 1990

Global food security requires that grain yields continue to increase to 2050, yet yields have stalled in many developed countries. This disturbing trend has so far been only partially explained. Here, we show that wheat yields in Australia have stalled since 1990 and investigate the extent to which climate trends account for this observation. Based on simulation of 50 sites with quality weather data, that are representative of the agro‐ecological zones and of soil types in the grain zone, we show that water‐limited yield potential declined by 27% over a 26 year period from 1990 to 2015. We attribute this decline to reduced rainfall and to rising temperatures while the positive effect of elevated atmospheric CO₂ concentrations prevented a further 4% loss relative to 1990 yields. Closer investigation of three sites revealed the nature of the simulated response of water‐limited yield to water availability, water stress and maximum temperatures. At all three sites, maximum temperature hastened time from sowing to flowering and to maturity and reduced grain number per m² and average weight per grain. This 27% climate‐driven decline in water‐limited yield is not fully expressed in actual national yields. This is due to an unprecedented rate of technology‐driven gains closing the gap between actual and water‐limited potential yields by 25 kg ha^?1 yr^?1 enabling relative yields to increase from 39% in 1990 to 55% in 2015. It remains to be seen whether technology can continue to maintain current yields, let alone increase them to those required by 2050.     

复杂型Stanford B型主动脉夹层腔内修复术中左锁骨下动脉重建方式分析

目的:总结复杂型Stanford B型主动脉夹层中左锁骨下动脉重建的经验和方法。方法:2010年4月至2016年5月,共有43例复杂型Stanford B型主动脉夹层采用腔内修复术治疗,并均重建左锁骨下动脉,其中右腋动脉-左腋动脉人工血管旁路18例,开窗技术14例,烟囱技术11例。结果:均成功手术,无术中死亡,术后造影显示支架敷贴良好,定位准确,左锁骨下动脉血流通畅。术后无头晕症状,双上肢血压差均在15 mmHg之内。1例术后5天并发逆行性A型夹层猝死。肾功能衰竭2例,行透析治疗后治愈。随访38例,失访4例,随访时间2~33月(17.0士5.2月),1例患者术后45天猝死;术后3月、1年复查主动脉CTA均示支架无移位。1例I型内漏,术后8月复查CTA示内漏消失;1例术后9月人工血管内血栓形成,中段狭窄约40%;2例并发支架远端动脉瘤形成。结论:腋动脉人工血管旁路术、开窗技术、烟囱技术进行左锁骨下动脉重建,联合主动脉腔内修复术治疗复杂型Standford B型主动脉夹层,可以取得满意的临床效果。     

猕猴桃果实采后生理研究进展

猕猴桃（Actinidia chinensis Planch.）属于呼吸跃变型果实,采后易软化腐烂,不耐贮藏,如何延长猕猴桃果实贮藏期限已成为猕猴桃产业发展壮大亟待解决的问题。猕猴桃果实采后生理变化强烈影响果实的贮藏期限和果实品质,特别是呼吸作用、乙烯合成及其信号转导系统和果实软化等,并且它们与猕猴桃贮藏保鲜技术的研发与应用密切相关。本文重点从这3个方面就国内外相关研究进展进行综述,并讨论它们对猕猴桃耐贮性的影响,以期为猕猴桃耐贮新品种的培育和贮藏保鲜技术的研发提供理论依据。