Antiviral activity of some derivatives of 2-styrylquinoline

Zusammenfassung In Mäuseversuchen wurde gezeigt, dass gewisse Styrylquinoline in vivo eine Wirkung gegen Semliki-Forest-Virus haben.     

Detection of complement-producing cells with macrophage antiserum

Résumé Exposé d'une méthode utilisant un antisérum macrophage hautement spécifique de lapin pour rendre apparente et identifier des cellules sécrétant du C4 dans les exudations du péritoine du cobaye.     

TNF ligands: is TALL-1 a trimer or a virus-like cluster?

Native TALL-1 (B-cell activation factor, BAFF; also known as BlyS) was initially described as a homotrimer, but Liu and colleagues claim that it is a 60-subunit complex on the basis of their results from X-ray crystallography and size-exclusion chromatography. They consider TALL-1 60-mers to be the biologically active form, and the arrangement of the 60-mers resembles that of the capsid of satellite tobacco necrosis virus. Here we show that active TALL-1 is trimeric under normal physiological conditions and that formation of higher-order oligomers is an artefact of tagging the amino terminus of the protein with a histidine tag.     

A possible terrestrial analogue for haematite concretions on Mars

Recent exploration has revealed extensive geological evidence for a water-rich past in the shallow subsurface of Mars. Images of in situ and loose accumulations of abundant, haematite-rich spherical balls from the Mars Exploration Rover 'Opportunity' landing site at Meridiani Planum bear a striking resemblance to diagenetic (post-depositional), haematite-cemented concretions found in the Jurassic Navajo Sandstone of southern Utah. Here we compare the spherical concretions imaged on Mars to these terrestrial concretions, and investigate the implications for analogous groundwater-related formation mechanisms. The morphology, character and distribution of Navajo haematite concretions allow us to infer host-rock properties and fluid processes necessary for similar features to develop on Mars. We conclude that the formation of such spherical haematite concretions requires the presence of a permeable host rock, groundwater flow and a chemical reaction front.     

Quality assessment of the human genome sequence

As the final sequencing of the human genome has now been completed, we present the results of the largest examination of the quality of the finished DNA sequence. The completed study covers the major contributing sequencing centres and is based on a rigorous combination of laboratory experiments and computational analysis.     

The DNA sequence and comparative analysis of human chromosome 5

Chromosome 5 is one of the largest human chromosomes and contains numerous intrachromosomal duplications, yet it has one of the lowest gene densities. This is partially explained by numerous gene-poor regions that display a remarkable degree of noncoding conservation with non-mammalian vertebrates, suggesting that they are functionally constrained. In total, we compiled 177.7 million base pairs of highly accurate finished sequence containing 923 manually curated protein-coding genes including the protocadherin and interleukin gene families. We also completely sequenced versions of the large chromosome-5-specific internal duplications. These duplications are very recent evolutionary events and probably have a mechanistic role in human physiological variation, as deletions in these regions are the cause of debilitating disorders including spinal muscular atrophy.     

基于密度依赖模型的广州制造业企业死亡风险研究

本文分析在同一个产业环境中不同组织形式的演化特征,概括它们之间的竞争和协作关系,判断这些关系对制造业中组织演化的影响,在此基础上提出有利于广州制造业持续发展的调控对策和建议。本文利用组织生态学中的种群密度依赖原理及时变变量Cox模型分析广州制造业企业死亡风险,得出以下结论:（1）2000年-2012年期间,广州制造业的种群密度与组织死亡风险呈正向的关系;（2）组织年龄与组织死亡风险呈负向的关系,且组织年龄可以抑制种群密度对组织死亡的影响;（3）在相同的组织年龄水平下多元化企业面临的死亡风险大于专一型企业的死亡风险,并且随着组织年龄的增大,两者的死亡风险差距逐渐扩大;（4）种群密度对外资企业死亡风险的影响大于对内资企业死亡风险的影响。但外资企业一旦存活,随之组织年龄的增大,其死亡风险跟内资企业面临的死亡风险基本相同;（5）种群密度对非劳动密集型企业死亡风险的影响大于对劳动密集型企业的死亡风险。     

Probable heat capacity signature of the supersolid transition

Liquid 4He enters the superfluid state and flows without friction below 2.176 K. Thin liquid films adsorbed on solid substrates undergo the same transformation, although at a lower temperature. When the substrate is subjected to oscillatory motion a portion of the film, known as the superfluid fraction, decouples from the oscillation. A similar phenomenon has been observed in solid 4He, in which a fraction of the solid seems to decouple from the motion of the surrounding lattice. Although this observation has been replicated in various laboratories, no thermodynamic signature of the possible supersolid transition has been seen. Here we report the finding of a heat capacity peak that coincides with the onset of mass decoupling. This complementary experimental evidence supports the existence of a genuine transition between the normal solid and supersolid phases of 4He.     

粉煤灰微波改性及其对甲基橙的吸附性能

将取自于热电厂的粉煤灰(FA)球磨5h得到超细粉煤灰(UFA),再经过微波处理得到微波辐照改性超细粉煤灰(MFA),并研究其对水溶液中甲基橙的吸附性能。动力学研究结果表明,改性粉煤灰对甲基橙的吸附符合二级吸附动力学模型,通过模型计算出的FA,UFA和MFA的二级吸附速率常数(k2)分别为9.30×10-3,13.00×10-3,18.35×10-3g.mg-1.min-1;热力学研究结果表明,吸附过程可以用Langmuir方程描述。计算吸附热力学参数ΔG,ΔS和ΔH,FA,UFA和MFA对甲基橙的吸附焓(ΔH)分别为-23.03,-25.98和-29.42kJ·mol-1。ΔG和ΔH均为负值,表明吸附为一自发的放热过程。     

鬼箭锦鸡儿细胞毒活性成分研究

 运用中压柱色谱和高效制备液相色谱方法对藏药鬼箭锦鸡儿的化学成分进行分离纯化,利用现代波谱技术鉴定所分离化合物的结构,并对所得到的化合物进行体外抗肝癌活性测试.从鬼箭锦鸡儿乙醇提取物中分离得到8个单体化合物,分别鉴定为6,7,3′-三羟基-4′-甲氧基异黄酮（1）、3,7-二羟基-4′-甲氧基黄酮（2）、3-甲氧基-4,9-二羟基紫檀素（3）、7,3′-二羟基-5′-甲氧基异黄酮（4）、6,7-二羟基-4′-甲氧基异黄酮（5）、3,9-二甲氧基-8-羟基紫檀素（6）、3,9-二甲氧基-4-羟基紫檀素（7）和3-甲氧基-4-羟基高丽槐素（8）,所有的化合物为首次从该植物中分离得到.采用MTT法对化合物1～8进行体外抗肝癌活性测试,结果显示所有的化合物对2个肝癌细胞株HepG2和Hep3B均有抑制作用,它们的IC50值范围为22.5～104.7μg/mL.