Interpolymer radical coupling: A toolbox complementary to controlled radical polymerization

The current review focuses on the relevance and practical benefit of interpolymer radical coupling methods. The latter are developing rapidly and constitute a perfectly complementary macromolecular engineering toolbox to the controlled radical polymerization techniques (CRP). Indeed, all structures formed by CRP are likely to be prone to radical coupling reactions, which multiply the available synthetic possibilities. Basically, the coupling systems can be divided in two main categories. The first one, including the atom transfer radical coupling (ATRC), silane radical atom abstraction (SRAA) and cobalt-mediated radical coupling (CMRC), relies on the recombination of macroradicals produced from a dormant species. The second one, including atom transfer nitroxide radical coupling (ATNRC), single electron transfer nitroxide radical coupling (SETNRC), enhanced spin capturing polymerization (ESCP) and nitrone/nitroso mediated radical coupling (NMRC), makes use of a radical scavenger in order to promote the conjugation of the polymer chains. More than a compilation of macromolecular engineering achievements, the present review additionally aims to emphasize the particularities, synthetic potential and present limitations of each system.     

农业机械产品数字化设计技术及展望

针对数字化设计技术的定义分析了其特点，阐述了当今数字化设计技术研究的热点——计算机辅助概念设计、知识工程、虚拟原型技术；探讨了机械产品数字化设计技术的研究现状及未来的发展趋势，即突出产品创新设计、重视虚拟现实技术、强调产品协同设计；数字化设计技术作为国家中长期科学技术发展规划优先扶持的主题，其应用将会使传统的农业机械设计制造技术发生革命性的变化。     

南京广电网络客户服务系统组成及维护管理

本文主要介绍了南京广电网络客户服务系统的组成结构、主要设备及功能应用,对广电客服系统现有关键设备的工作原理和技术特点进行了简要分析论述,对系统维护操作和管理应急情况提出了相应处理方法和实际解决方案。     

Optimizing use of the structural chemical analyser (variable pressure FESEM‐EDX raman spectroscopy) on micro‐size complex historical paintings characterization

The novel Structural Chemical Analyser (hyphenated Raman spectroscopy and scanning electron microscopy equipped with an X‐ray detector) is gaining popularity since it allows 3‐D morphological studies and elemental, molecular, structural and electronic analyses of a single complex micro‐sized sample without transfer between instruments. However, its full potential remains unexploited in painting heritage where simultaneous identification of inorganic and organic materials in paintings is critically yet unresolved. Despite benefits and drawbacks shown in literature, new challenges have to be faced analysing multifaceted paint specimens. SEM?Structural Chemical Analyser systems differ since they are fabricated ad hoc by request. As configuration influences the procedure to optimize analyses, likewise analytical protocols have to be designed ad hoc. This paper deals with the optimization of the analytical procedure of a Variable Pressure Field Emission scanning electron microscopy equipped with an X‐ray detector Raman spectroscopy system to analyse historical paint samples. We address essential parameters, technical challenges and limitations raised from analysing paint stratigraphies, archaeological samples and loose pigments. We show that accurate data interpretation requires comprehensive knowledge of factors affecting Raman spectra. We tackled: (i) the in‐FESEM?Raman spectroscopy analytical sequence, (ii) correlations between FESEM and Structural Chemical Analyser/laser analytical position, (iii) Raman signal intensity under different VP‐FESEM vacuum modes, (iv) carbon deposition on samples under FESEM low‐vacuum mode, (v) crystal nature and morphology, (vi) depth of focus and (vii) surface‐enhanced Raman scattering effect. We recommend careful planning of analysis strategies prior to research which, although time consuming, guarantees reliable results. The ultimate goal of this paper is to help to guide future users of a FESEM‐Structural Chemical Analyser system in order to increase applications.     

中蜂囊状幼虫病毒VP1基因的优化表达及其免疫原性分析

目的原核表达优化的中蜂囊状幼虫病毒(Chinese sacbrood virus,CSBV)的VP1基因,并分析其免疫原性。方法根据大肠埃希菌密码子偏爱性对野生型CSBV VP1(wt VP1)基因进行优化(opti VP1),将基因wt VP1和opti VP1分别克隆至p GEX-6P-1原核表达系统,构建原核表达质粒p GEX-6P-wt VP1和p GEX-6P-opti VP1,分别转化E.coli BL21,经IPTG诱导表达,并对诱导温度、IPTG终浓度及诱导时间进行优化,诱导蛋白经Western blot鉴定;重组蛋白经GSH-琼脂糖凝胶层析纯化;分别用PBS、纯化的GST标签蛋白、纯化的重组蛋白及CSBV纯化病毒免疫小鼠,经间接ELISA法检验各组小鼠的血清抗体效价。结果优化后的VP1基因序列降低了密码子影响指数,提高了密码子适应指数;质粒p GEX-6P-wt VP1和p GEX-6P-opti VP1经鉴定证明构建正确;最佳诱导表达条件为:IPTG终浓度0.8 mmol/L,30℃,220 r/min诱导8 h;诱导表达蛋白占菌体总蛋白百分比由wt VP1菌株(5.49±0.30)%提高至opti VP1菌株(59.7±0.51)%,纯化后纯度可达0.5 mg/ml;兔抗GST标签抗体及兔抗CSBV血清均与优化后的重组蛋白发生特异性反应;重组蛋白组小鼠二免后可产生较高水平抗体,明显高于PBS组和GST标签蛋白组(P0.05)。结论通过密码子优化实现了CSBV结构基因VP1的高效表达,表达蛋白可诱导小鼠机体产生特异性抗体,具有良好的免疫原性,为探讨CSBV感染的分子发病机制和制备抗CSBV病毒的多克隆抗体奠定了基础。     

横河DCS在连续PET生产中应用

介绍了YOKOGAWA公司的CENTUM VP在连续PET生产中的应用情况,以某一具体连续PET项目为例简述了控制系统硬件软件配置,以及具体的硬件软件组态过程,其中重点以酯化釜流程为例介绍了复杂控制方案的组态。     

ATM网络VP带宽动态管理策略的研究

文章介绍了一种适合于混合业务类型、非均匀业务流两步长VP动态带宽管理策略，分析了带宽管理策略的带宽利用率、连接阻塞概率和带宽分配处理负载，对其进行了计算机模拟仿真，并与固定步长动态带宽管理策略进行了分析比较。     

四种不同气调包装的冷却猪肉在冷藏过程中的理化及感官变化

冷却猪肉分别采取真空包装、CO-MAP(CO+CO2+N2)包装、高氧-MAP(高浓度O2+CO2+N2)和低氧-MAP(低浓度O2+CO2+N2)包装后,在(4±1℃)贮存三周,每周测定各项理化指标(TVB-N和TBARS),并进行感官评定。结果表明:1)采用CO-MAP包装的冷却猪肉在贮存过程中不仅TVB-N和TBARS较低,而且红色稳定无任何异味。2)真空包装组的冷却猪肉在贮存期间TVB-N和TBARS也较低,在贮存末期呈淡紫色有轻微异味。3)含氧气调包装中,冷却猪肉的TVB-N值和TBARS值相对较高,特别是脂肪氧化加速,鲜红色泽1周后很快变为褐色,并有不良气味产生,所以含氧包装仅适合保质期在1周以内的冷却猪肉。     

不同气调包装对冷却猪肉在冷藏过程中的微生物变化的研究

冷却猪肉分别采取真空包装、CO-MAP(CO+CO2+N2)包装、高氧-MAP(高浓度O2+CO2+N2)和低氧-MAP(低浓度O2+CO2+N2)包装后,在(4±1℃)贮存三周,每周测定各项微生物的变化。结果表明:1)CO-MAP和真空包装在贮存末期的优势菌为乳酸菌而含氧气调包装的优势菌是假单胞菌属。2)CO-MAP组可抑制腐败细菌的生长除对乳酸菌抑制作用较弱外,对假单胞菌、肠杆菌科菌均具有很强的抑制作用,其对腐败菌的抑制作用明显好于真空包装组。     

EGFR-Binding Peptides: From Computational Design towards Tumor-Targeting of Adeno-Associated Virus Capsids

The epidermal growth factor receptor (EGFR) plays a central role in the progression of many solid tumors. We used this validated target to analyze the de novo design of EGFR-binding peptides and their application for the delivery of complex payloads via rational design of a viral vector. Peptides were computationally designed to interact with the EGFR dimerization interface. Two new peptides and a reference (EDA peptide) were chemically synthesized, and their binding ability characterized. Presentation of these peptides in each of the 60 capsid proteins of recombinant adeno-associated viruses (rAAV) via a genetic based loop insertion enabled targeting of EGFR overexpressing tumor cell lines. Furthermore, tissue distribution and tumor xenograft specificity were analyzed with systemic injection in chicken egg chorioallantoic membrane (CAM) assays. Complex correlations between the targeting of the synthetic peptides and the viral vectors to cells and in ovo were observed. Overall, these data demonstrate the potential of computational design in combination with rational capsid modification for viral vector targeting opening new avenues for viral vector delivery and specifically suicide gene therapy.