Different localization of reserpine and tyramine within the 5-hydroxytryptamine organelles of blood platelets

Zusammenfassung Die subzelluläre Lokalisation von Reserpin und Tyramin in Blutplättchen von Kaninchen erfolgt in vitro und in vivo grösstenteils in den 5-Hydroxytryptamin (5HT)-Organellen. Dabei reichert sich Reserpin vorwiegend in der Membran, Tyramin hauptsächlich im Inneren der Organellen an. Es wird vermutet, dass Reserpin in bezug auf 5HT-Freisetzung an der Membran und Tyramin im Inneren der 5HT-Organellen angreift.     

Evidence for cultivar adoption and emerging complexity during the mid-Holocene in the La Plata basin

Multidisciplinary investigations at the Los Ajos archaeological mound complex in the wetlands of southeastern Uruguay challenge the traditional view that the La Plata basin was inhabited by simple groups of hunters and gatherers for much of the pre-Hispanic era. Here we report new archaeological, palaeoecological and botanical data indicating that during an increasingly drier mid-Holocene, at around 4,190 radiocarbon (14C) years before present (bp), Los Ajos became a permanent circular plaza village, and its inhabitants adopted the earliest cultivars known in southern South America. The architectural plan of Los Ajos during the following Ceramic Mound Period (around 3,000-500 14C yr bp) is similar to, but earlier than, settlement patterns demonstrated in Amazonia, revealing a new and independent architectural tradition for South America.     

Blue emission from hydrogen-containing a-Si：H／SiO2 multilayers and the investigation of its mechanism

A series of hydrogen-containing a-Si:H/SiO2 multilayers with different a-Si:H sublayer thickness were fabricated by layer-by-layer deposition and in situ plasma oxidation in a plasma-enhanced chemical vapor deposition system (PECVD). Optical induced blue emission from the samples was observed by the naked eye at room temperature, which has never been reported in the luminescence study of Si/SiO2 multilayers up to now. Both the photoluminescence (PL) peak and the absorption edge show a blue shift as the a-Si:H sublayer thickness decreases. The origin of the blue emission and the effect of hydrogen are discussed.     

Horizontal gene transfer from Eukarya to Bacteria and domain shuffling: the α-amylase model

-Amylases are present in all kingdoms of the living world. Despite strong conservation of the tertiary structure, only a few amino acids are conserved in interkingdom comparisons. Animal -amylases are characterized by several typical motifs and biochemical properties. A few cases of such -amylases have been previously reported in some eubacterial species. We screened the bacterial genomes available in the sequence databases for new occurrences of animal-like -amylases. Three novel cases were found, which belong to unrelated bacterial phyla: Chloroflexus aurantiacus, Microbulbifer degradans, and Thermobifida fusca. All the animal-like -amylases in Bacteria probably result from repeated horizontal gene transfer from animals. The M. degradans genome also contains bacterial-type and plant-type -amylases in addition to the animal-type one. Thus, this species exhibits -amylases of animal, plant, and bacterial origins. Moreover, the similarities in the extra C-terminal domains (different from both the -amylase domain C and the starch-binding domain), when present, also suggest interkingdom as well as intragenomic shuffling.Received 17 October 2003; accepted 6 November 2003     

A missense mutation in Tbce causes progressive motor neuronopathy in mice

Mice that are homozygous with respect to the progressive motor neuronopathy (pmn) mutation (chromosome 13) develop a progressive caudio-cranial degeneration of their motor axons from the age of two weeks and die four to six weeks after birth. The mutation is fully penetrant, and expressivity does not depend on the genetic background. Based on its pathological features, the pmn mutation has been considered an excellent model for the autosomal recessive proximal childhood form of spinal muscular atrophy (SMA). Previously, we demonstrated that the genes responsible for these disorders were not orthologous. Here, we identify the pmn mutation as resulting in a Trp524Gly substitution at the last residue of the tubulin-specific chaperone e (Tbce) protein that leads to decreased protein stability. Electron microscopy of the sciatic and phrenic nerves of affected mice showed a reduced number of microtubules, probably due to defective stabilization. Transgenic complementation with a wildtype Tbce cDNA restored a normal phenotype in mutant mice. Our observations indicate that Tbce is critical for the maintenance of microtubules in mouse motor axons, and suggest that altered function of tubulin cofactors might be implicated in human motor neuron diseases.     

履带式推土机粘弹性悬挂机构的开发研究

对履带式推土机行走机构的振动特性进行测试 ,建立起推土机缓冲系统模型 ,经对模型特性参数对传递率影响的分析 ,确定出参数的合理值域。把阻尼材料诺模图曲线数字化 ,做到了计算机对诺模图动态曲线的自动查询 ,实现了阻尼缓冲结构的动态优化。掌握了阻尼缓冲结构的设计理论和方法 ,已应用于 2 4 2kW履带式推土机粘弹性悬挂机构的开发。     

Web Services在大型旋转机械在线诊断系统中的应用

Web Services是实现信息发布的一种软件与通讯技术。提出了Web Services技术与设备故障诊断技术结合的全新思路,将设备的工艺流程、工艺参数、信号特征、故障推理诊断结论等通过软件与通讯的方式实现数据的动态交换和人机界面(HMI)的交互,供用户操作,从而形成网络化的系统信息发布。介绍了Web Services的基本原理和特点,结合国家“十五”计划“八六三”项目课题“网络化、智能化大型旋转机械在线诊断系统”,对在线诊断系统中信息发布的常见内容进行了归纳分类,描述如何采用DELPHI6 Web Services组件,实现网络化、智能化大型旋转机械在线诊断系统的信息发布、查询等功能。     

Behaviourally driven gene expression reveals song nuclei in hummingbird brain

Hummingbirds have developed a wealth of intriguing features, such as backwards flight, ultraviolet vision, extremely high metabolic rates, nocturnal hibernation, high brain-to-body size ratio and a remarkable species-specific diversity of vocalizations. Like humans, they have also developed the rare trait of vocal learning, this being the ability to acquire vocalizations through imitation rather than instinct. Here we show, using behaviourally driven gene expression in freely ranging tropical animals, that the forebrain of hummingbirds contains seven discrete structures that are active during singing, providing the first anatomical and functional demonstration of vocal nuclei in hummingbirds. These structures are strikingly similar to seven forebrain regions that are involved in vocal learning and production in songbirds and parrots--the only other avian orders known to be vocal learners. This similarity is surprising, as songbirds, parrots and hummingbirds are thought to have evolved vocal learning and associated brain structures independently, and it indicates that strong constraints may influence the evolution of forebrain vocal nuclei.     

工业园区规划理念与功能布局研究

通过对临汾段店工业园区控制性详细规划设计理念和功能布局的论述,提出以中、高技术产业为主,集科、工、贸于一体,多功能、综合性的现代化、花园式的城市功能区是工业园区发展的方向。