Neutralizing human monoclonal antibodies binding multiple serotypes of botulinum neurotoxin

Botulism, a disease of humans characterized by prolonged paralysis, is caused by botulinum neurotoxins (BoNTs), the most poisonous substances known. There are seven serotypes of BoNT (A-G) which differ from each other by 34-64% at the amino acid level. Each serotype is uniquely recognized by polyclonal antibodies, which originally were used to classify serotypes. To determine if there existed monoclonal antibodies (mAbs) capable of binding two or more serotypes, we evaluated the ability of 35 yeast-displayed single-chain variable fragment antibodies generated from vaccinated humans or mice for their ability to bind multiple BoNT serotypes. Two such clonally related human mAbs (1B18 and 4E17) were identified that bound BoNT serotype A (BoNT/A) and B or BoNT/A, B, E and F, respectively, with high affinity. Using molecular evolution techniques, it proved possible to both increase affinity and maintain cross-serotype reactivity for the 4E17 mAb. Both 1B18 and 4E17 bound to a relatively conserved epitope at the tip of the BoNT translocation domain. Immunoglobulin G constructed from affinity matured variants of 1B18 and 4E17 were evaluated for their ability to neutralize BoNT/B and E, respectively, in vivo. Both antibodies potently neutralized BoNT in vivo demonstrating that this epitope is functionally important in the intoxication pathway. Such cross-serotype binding and neutralizing mAbs should simplify the development of antibody-based BoNT diagnostics and therapeutics.     

Asymmetric anatase TiO₂ nanocrystals with exposed high-index facets and their excellent lithium storage properties

In this work, we demonstrate a unique organic solvent system to synthesize asymmetric anatase TiO(2) nanocrystals with a bipyramidal structure, where the upper pyramid is bound by (201) facets, and the lower pyramid is bound by (401) surfaces. Due to the high surface energy of these (401) high-index facets, the nanocrystals tend to assemble on these facets to minimize the free energy, leading to the formation of a dandelion-like hierarchical structure.     

未来油品零售业的电子化服务

介绍了未来油品零售业网上服务的的发展阶段及其需要解决的问题，指出加油站的非燃料服务是增加加油站效益的重要途径，同时分析了加油站电子服务的现状及前景。     

世界LNG市场贸易现状与发展趋向

阐述了世界LNG生产能力和市场贸易现状，分析了推动LNG需求上升的因素。预计随着LNG短期现货贸易的持续扩大、LNG供应成本的不断降低以及LNG贸易更加趋于全球化，世界传统的LNG贸易格局将被打破。     

高纯过氧化氢的生产及应用

简单介绍了高纯过氧化氢的规格和分析方法，详述了各种高纯过氧化氢制造技术，综述了国内外高纯过氧化氢的生产应用现状和发展趋势。     

灭蝇胺复配剂对美洲斑潜蝇田间防效

田间试验结果表明,50%灭蝇胺+杀螟丹WP 1 000~2 000倍液,86%灭蝇胺+敌敌畏OF、50%灭蝇胺+毒死蜱1 000倍液防治美洲斑潜蝇,其杀虫效果90%左右,保苗效果80%左右,持效期10 d以上。试验浓度范围内对黄瓜苗安全。     

High-performance antiferroelectric ceramics via multistage phase transition

Lead-based antiferroelectric (AFE) ceramics have attracted increasing interest in pulse power systems owing to their high-energy storage and power densities. However, the single AFE–ferroelectric (FE) phase transition in conventional AFE materials usually leads to premature polarization saturation and low breakdown strength, which are disadvantageous to energy storage performance. In this study, high energy storage performance was achieved in Pb_0.94−xLa_0.04Ca_x[Nb_0.02(Zr_0.99Ti_0.01)_0.975]O₃ (PLCNZT) AFE ceramics by constructing electric-field-induced multiple phase transitions. A maximum recoverable energy storage density of 12.15 J/cm³ and a high energy efficiency of 85.4% were obtained for the PLCNZT ceramic with x = 0.03 at 420 kV/cm. These excellent properties are attributed to the AFE–FE Ⅰ-FE Ⅱ multiple phase transitions induced by Ca²⁺ doping, which effectively enhances the breakdown strength. This result indicates that field-induced multiple phase transitions significantly improve the energy storage of AFE materials.     

超声波降解全氟丁酸水溶液

全氟丁酸(PFBA)作为全氟辛烷磺酸基化合物(PFOs)和全氟辛酸化合物(PFOA)的替代品,相对于PFOS和PFOA,因水溶解度更大和碳链短等特点造成PFBA更难处理和代谢[1-2].     

前置胎盘合并瘢痕子宫剖宫产术35例临床分析

目的探讨前置胎盘合并瘢痕子宫剖宫产患者的临床分析。方法将瘢痕组35例和对照组(非瘢痕组)35例临床表现进行对比,进行观察。结果瘢痕组患者并发症的概率远高于对照组,瘢痕组围产儿早产和窒息的概率也远高于对照组,P<0.05。结论大力提倡自然分娩,降低剖宫产率,能有效避免凶险性前置胎盘的发生,降低母婴死亡率。     

炉膛火焰温度场图象处理试验研究

借助于计算机图象获取、处理技术，本文提出了一种简单有效的全炉膛火焰二维温度场分布计测方法。以辐射定律为基础对这种方法的基本原理和特点进行了介绍。然后，对一台试验炉的燃烧火焰进行了实验测定，对所摄图象进行了滤波等必要的处理，最后显示了火焰的温度场，以及对燃烧火焰的初步诊断结果。可望将此方法应用于电站锅炉的燃烧监测与管理系统中。