Magnetic resonance imaging based volumetry:a primary approach to unravelling the brain

Magnetic resonance(MR)imaging based volumetry is recognized as an important technique for studying the brain.In this review,two principle volumetric methods using high resolution MR images were introduced,namely the Cavalieri method and the voxel based morphometry(VBM).The Cavalieri method represents a manual technique that allows the volume of brain structures to be estimated efficiently with no systematic error or sampling bias,whereby the VBM represents an automated image analysis which involves the use of statistical parametric mapping of the MR imaging data.Both methods have been refined and applied extensively in recent neuro- science research.The present paper aims to describe the development of methodologies and also to update the knowledge of their applica- tions in studying the normal and diseased brain.     

Mating behaviour and maternal care in the tropical savanna funnel-web spider Aglaoctenus lagotis Holmberg (Araneae: Lycosidae)

Despite their abundance and diversity, Neotropical spiders have been the subject of relatively few studies of behavioural ecology. The sexual behaviour and maternal care of the spider Aglaoctenus lagotis (Lycosidae) is described here. We performed experimental manipulations to test the hypothesis that males are attracted by female cues in the web. Two predictions were tested: (a) webs used by a virgin female will attract more males than webs used by an inseminated female; (b) the main cue in the web is chemical, so webs recently used by virgin females will attract more males than those that are not recently used. Additionally, we tested the hypothesis that maternal care increases offspring survivorship. Results showed that males are attracted by recently used webs (z = 0.0015; p = 0.037; z-test) and webs of virgin females (z = 0.041; p = 0.036, z-test). Male sexual behaviour presented three different categories: court, pre-mate and mate. After the mating, the females built a cocoon that was transported adhered to the spinnerets and held by the last pair of legs. After the hatching of the eggs, the young migrated to the dorsal region of the mother's body for 5 days. During maternal care the mother eliminates a yellowish drop from its oral cavity, which is collected by the young. During the development of the young until adulthood, the offspring that have their mother present in the first stages of life have greater survival compared with those without maternal care. Our results make it possible to perform comparative analyses between a South American Lycosidae species and other species distributed worldwide.     

Immunocytochemical localization of GnRH (gonadotropin releasing hormone) systems in the brain of a marine teleost fish,the sole

Summary The GnRH system was studied in the brain of the sole by immunocytochemistry (peroxidase-antiperoxidase method) (PAP) using antibodies to synthetic salmon GnRH (s-GnRH). Two centers containing immunoreactive cell bodies were observed in the forebrain, one located at the junction between the olfactory bulbs and the telencephalon and the other in the preoptic area. Numerous immunoreactive fibers were found, especially in the telencephalon, hypothalamus, pituitary, optic tectum and retina.     

关于企业内部创新模式的探讨

在组织内部形成创新方案的模式，即组织要在内部组建创新团队，并为团队提供自由空间，使创新团队能够从技术、个人、组织等三个角度研究并提出创新方案，然后，综合基于三个角度创新方案的优点，形成综合最佳方案。     

天冬氨酸对家鸽顶盖脑片Ⅱa—f层神经元电活动的影响

利用离体脑片技术，在５１例家鸽顶盖脑片上用玻璃微电极胞外记录了家鸽顶盖Ⅱａ－ｆ亚层神经元的自发放电活动。根据家鸽顶盖Ⅱａ－ｆ 层神经元自发放电活动的特征，将Ⅱａ－ｆ亚层神经元自发放电分为３种类型：慢而不规则型、快连续型和周期性簇状放电型。天冬氨酸（Ａｓｐ）对不同形式放电单位的作用均以兴奋为主，这种兴奋作用能被Ｎ－甲基－Ｄ－天冬氨酸（ＮＭＯＡ）增强，Ｄ－α－氨基－己二酸（Ｄ－α－ＡＡ）能阻断ＡＳＰ的     

民营小企业如何化解员工培训与人才流失的矛盾

员工培训是民营小企业发展的内在动力和必然要求，培训能够提高员工综合素质，增加员工个人利益，提升企业综合竞争力。目前民营小企业在员工培训上还远没有形成一套科学规范的体系，经费投入很少，更没有对教育培训实施有效的评估，员工参与教育培训的机会不多。其根本原因在于人才流失现象非常严重，培训与流失矛盾十分突出。化解员工培训与人才流失的矛盾应该从员工培训入手，一方面，通过加强培训并辅以其他措施来留住人才，另一方面，通过稳定人才来促进员工培训。     

未知相关噪声下的广义波达方向估计算法

针对未知相关噪声情况下信源波达方向的估计,提出一种适用于均匀线阵的广义波达方向估计算法。该算法利用修正后的协方差差分算法,有效地消除了阵元间的相关噪声的影响。不同于以前的算法,提出的算法通过对接收数据的前后向空间平滑协方差矩阵进行共轭运算得到新的变换矩阵,因此修正后的协方差差分矩阵是个实部为零的厄米特矩阵,从而有效地降低了特征分解过程的计算量。本算法能解决相关噪声下,同时分辨相干与非相干信源的问题。理论分析和仿真结果均表明所提算法的有效性。     

Extracellular matrix and neuronal movement

Summary During brain development, both neuronal migration and axon guidance are influenced by extracellular matrix molecules present in the environment of the migrating neuronal cell bodies and nerve fibers. Glial laminin is an extracellular matrix protein which these early brain cells preferentially attach to. Extracellular glycosaminoglycans are suggested to function in restricting neuronal cell bodies and axons from certain brain areas. Since laminin is deposited along the radial glial fibers and along the developing nerve pathways in punctate form, the punctate assemblies may be one of the key factors in routing the developing neurons in vivo. This review discusses the role of laminin in neuronal movement given the present concept of the extracellular matrix molecules and their proposed interactions.     

Effect of phospholipids on purified lipoamidase

Summary Phospholipids were added to purified lipoamidase from porcine brain microsomal membranes, and changes in lipoamidase activity were examined. Approximately twofold activation of lipoamidase activity occurred upon the addition of phosphatidylethanolamine. On the other hand, phosphosphatidylserine, cardiolipin, and phosphatidic acid reduced the enzyme activity by approximately 80%. This pattern of the activation of lipoamidase by phosphatidylethanolamine and its inhibition by phosphatidylserine is similar to the pattern for adenylate cyclase, and contrasts with the pattern for ATPase.     

MMDS的信号传播及系统设计

分析ＭＭＤＳ的天线及信号传播特性，并根据这些特性和工程的实际需要探讨了发射系统的工程设计方法和抗干扰措施。