Rapid extragranular plasticity in the absence of thalamocortical plasticity in the developing primary visual cortex

Monocular deprivation during early postnatal development remodels the circuitry of the primary visual cortex so that most neurons respond poorly to stimuli presented to the deprived eye. This rapid physiological change is ultimately accompanied by a matching anatomical loss of input from the deprived eye. This remodeling is thought to be initiated at the thalamocortical synapse. Ocular dominance plasticity after brief (24 hours) monocular deprivation was analyzed by intrinsic signal optical imaging and by targeted extracellular unit recordings. Deprived-eye responsiveness was lost in the extragranular layers, whereas normal binocularity in layer IV was preserved. This finding supports the hypothesis that thalamocortical organization is guided by earlier changes at higher stages.     

Interhemispheric transfer of plasticity in the cerebral cortex

Each half of the body surface is represented topographically in the contralateral cerebral hemisphere. Physiological data are presented showing that homotopic regions of primary somatosensory cortex are linked such that plasticity induced in one hemisphere, in the form of receptive field expansion brought about by a small peripheral denervation, is immediately mirrored in the other hemisphere. Neurons which display the plasticity show no responsiveness to stimulation of the ipsilateral body surface. This suggests that the pathways and mechanisms mediating this transfer are specific to the role of maintaining balance, or integration, between corresponding cortical fields.     

应用微卫星图谱定位稻米性状的QTL

以两系杂交稻强优组合培矮64s／E32的1个加倍单倍体(doubledhaploid，DH)群体(含有86个株系)为供试材料，利用福建农林大学遗传工程实验室已构建的微卫星标记连锁图，应用复合区间作图法对控制水稻糙米性状(粒长、粒宽和粒重)的QTL进行定位。在本试验中共定位了18个QTL，其中8个控制粒长。4个控制粒宽，6个控制粒重，它们对粒长、粒宽和粒重表型变异的贡献冯分别为78．61％、68．62％和72．06％。     

Reactivation of ocular dominance plasticity in the adult visual cortex

In young animals, monocular deprivation leads to an ocular dominance shift, whereas in adults after the critical period there is no such shift. Chondroitin sulphate proteoglycans (CSPGs) are components of the extracellular matrix (ECM) inhibitory for axonal sprouting. We tested whether the developmental maturation of the ECM is inhibitory for experience-dependent plasticity in the visual cortex. The organization of CSPGs into perineuronal nets coincided with the end of the critical period and was delayed by dark rearing. After CSPG degradation with chondroitinase-ABC in adult rats, monocular deprivation caused an ocular dominance shift toward the nondeprived eye. The mature ECM is thus inhibitory for experience-dependent plasticity, and degradation of CSPGs reactivates cortical plasticity.     

SD大鼠Barrel脑区氧化酶活性区域及其特殊细胞构筑研究

【目的】确定控制大鼠胡须感觉的大脑皮质Barrel脑区的氧化酶活性区和该区的细胞构筑,为研究大脑皮质功能奠定基础。【方法】用多聚甲醛固定后的SD鼠脑组织修块、切片,应用氧化酶酶组织化学法及尼氏染色和尼氏复染等方法定位了SD鼠Barrel脑区,并观察了其脑区特殊的细胞构筑。【结果】SD鼠Barrel脑区定位结果表明,控制SD鼠胡须感觉的Barrel脑区高氧化酶活性区域位于皮层下约405~720μm;脑区的神经细胞成特殊的环状分布,通常在控制1根胡须的Barrel桶内同时包括数目不等的亚结构,亦成类似的环状排列,在这些小圆环状亚结构中包含有排布规则的高活性氧化酶细胞。【结论】Barrel脑区的精细排布及其内部存在的圆环状细胞亚结构,提示这些结构在感觉皮层神经网络运作中发挥着重要作用。     

A map of visual space induced in primary auditory cortex

Maps of sensory surfaces are a fundamental feature of sensory cortical areas of the brain. The relative roles of afferents and targets in forming neocortical maps in higher mammals can be examined in ferrets in which retinal inputs are directed into the auditory pathway. In these animals, the primary auditory cortex contains a systematic representation of the retina (and of visual space) rather than a representation of the cochlea (and of sound frequency). A representation of a two-dimensional sensory epithelium, the retina, in cortex that normally represents a one-dimensional epithelium, the cochlea, suggests that the same cortical area can support different types of maps. Topography in the visual map arises both from thalamocortical projections that are characteristic of the auditory pathway and from patterns of retinal activity that provide the input to the map.     

Regional changes in calcium underlying contraction of single smooth muscle cells

The role of calcium in regulating the contractile state of smooth muscle has been investigated by measuring calcium and contraction in single smooth muscle cells with the calcium-sensitive dye fura-2 and the digital imaging microscope. The concentration of free calcium in the cytoplasm increased after stimulation of the cells by depolarization with high potassium or by application of carbachol. Changes in calcium always preceded contraction. The increase in calcium induced by these stimuli was limited to less than 1 microM. Calcium within the nucleus was also subject to a limitation of its rise during contraction. Intranuclear calcium rose from 200 nM at rest to no more than 300 nM while cytoplasmic calcium rose to over 700 nM. These apparent ceilings for both cytoplasmic and intranuclear calcium may result either from negative feedback of calcium on cytoplasmic and nuclear calcium channel gating mechanisms, respectively, or from the presence of calcium pumps that are strongly activated at the calcium ceilings.     

Visual instruction of the neural map of auditory space in the developing optic tectum

Neural maps of visual and auditory space are aligned in the adult optic tectum. In barn owls, this alignment of sensory maps was found to be controlled during ontogeny by visual instruction of the auditory spatial tuning of neurons. Large adaptive changes in auditory spatial tuning were induced by raising owls with displacing prisms mounted in spectacle frames in front of the eyes; neurons became tuned to sound source locations corresponding to their optically displaced, rather than their normal, visual receptive field locations. The results demonstrate that visual experience during development calibrates the tectal auditory space map in a site-specific manner, dictating its topography and alignment with the visual space map.     

大比例尺地形图数据库地物变化研究

为实现城市大比例尺地形图数据库的持续更新,在大比例尺地形图图式及地形图要素几何特征和属性项多寡的基础上,采用中华人民共和国国家标准《GB/T7929--1995,1∶500,1∶1 000,1∶2 000地形图图式》的地物要素分类方法,将大比例尺地形图数据的变化分类为图元对象或地理对象的变化、图层(或专题)的变化以及数据集的变化.对图元对象或地理对象的变化的内容进行了具体描述,包括产生、消失或版本变化,将这种描述记录在地形图数据库编辑软件的日志表中可以实现地形图的增量更新.     

橡胶种子、橡胶种子油的营养及食用安全性研究

\t\t\t\t\t目的\t\t\t\t\t评价日粮中配合不同比例的橡胶籽仁对蛋鸡生产性能和鸡蛋品质的影响。\t\t\t\t\t\t\t\t\t\t\t\t\t方法\t\t\t\t\t选取72只26周龄的健康海兰褐蛋鸡,随机分成6组,每组设4个重复,每个重复3只鸡,对照组饲喂玉米—豆粕型基础日粮,试验Ⅰ~Ⅴ组分别饲喂配合5%、10%、15%、20%和25%橡胶籽仁的同型日粮。各组日粮营养水平一致,试验期10周。\t\t\t\t\t\t\t\t\t\t\t\t\t结果\t\t\t\t\t与对照组相比,试验组日粮中配合橡胶籽仁对蛋鸡产蛋率、料蛋比和腹脂率影响差异不显著(P>0.05);平均日采食量Ⅰ、Ⅱ组与对照组差异不显著(P>0.05),Ⅲ、Ⅳ、Ⅴ组显著低于对照组(P<0.05);平均鸡蛋质量Ⅴ组显著低于对照组(P<0.05),Ⅰ至Ⅳ组与对照组差异不显著(P>0.05);蛋鸡体重Ⅱ组显著高于对照组(P<0.05),Ⅰ、Ⅲ、Ⅳ、Ⅴ组与对照组差异不显著(P>0.05)。蛋壳厚度、蛋形指数、蛋壳质量、蛋黄质量、蛋壳比、蛋黄比、蛋黄胆固醇和丙二醛含量试验组与对照组相比均无显著差异(P>0.05)。\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t结论\t\t\t\t\t日粮中配合5%~25%的橡胶籽仁不影响产蛋鸡产蛋率、料蛋比和蛋品质,但会减少蛋鸡采食量,且配合量达到25%会降低平均鸡蛋质量。\t\t\t\t     

鸡胚发育过程中垂体促乳素的表达及其细胞的发育

利用免疫荧光标记方法研究了鸡胚发育过程中垂体促乳素(PRL)细胞的发生。结果表明，在鸡胚发育的第14.5天可观察到有少量PRL免疫荧光阳性细胞散在分布于腺垂体前叶。随着胚龄的增加，垂体PRL细胞的体积逐渐增大。细胞直径从第14.5天的6.83μm增加到第20.5天的11.24μm，胞核直径从4.27μm增加到5.99μm。PRL细胞占腺垂体细胞总数的百分比在胚胎发育的第14.5天为0.86％，第20.5天增加到18.85％，并且分布于整个腺垂体前叶。细胞多呈索状排列或团状分布。研究结果表明。鸡胚垂体催乳素细胞的增殖、分化和对PRL的分泌功能主要发生和建立于胚胎发育后期。     

不同海拔油松和华山松林乔木层生物量与蓄积量的动态变化

【目的】探索秦岭火地塘林区不同海拔油松和华山松林林分生长变化趋势,为森林经营措施的制定提供理论依据。【方法】通过树木年轮学的方法,运用已有的生物量和材积回归方程,反演出1977-2011年秦岭火地塘林区不同海拔油松和华山松林乔木层生物量、生产力和蓄积量的动态变化特征。【结果】35年间不同海拔油松和华山松林乔木层生物量和蓄积量均增长迅速,且油松的增速一直快于华山松;油松林的生物量和蓄积量在海拔1 550~1 650m最大,生物量从1977年的44.40t/hm2增长到2011年的214.67t/hm2,蓄积量从54.98m3/hm2增长到237.50m3/hm2;华山松林的生物量和蓄积量在海拔1 850~2 000m最大,生物量从1977年的16.74t/hm2增长到2011年的182.75t/hm2,蓄积量从25.20m3/hm2增长到225.14m3/hm2;2种森林类型的生产力均随林龄的增大波动上升,在2001年左右达到最大值,随后生产力呈现下降趋势,同一树种不同海拔生产力波动趋势较一致。【结论】环境差异、人为干扰是造成不同海拔间林分生物量、蓄积量产生差异的主要因素;生物学特性和林分环境的共同作用导致了不同森林类型生物量和蓄积量的差异;不同海拔间生产力波动变化的一致性,在一定程度上反映了树木生长对气候因子的响应。     

X-ray diffraction study of the ultrathin Al2O3 layer on NiAl110

Ultrathin Al2O3 layers on alloys are used as templates for model catalysts, tunneling barriers in electronic devices, or corrosion-resistant layers. The complex atomic structure of well-ordered alumina overlayers on NiAl110 was solved by surface x-ray diffraction. The oxide layer is composed of a double layer of strongly distorted hexagonal oxygen ions that hosts aluminum ions on both octahedral and tetrahedral sites with equal probability. The alumina overlayer exhibits a domain structure that can be related to characteristic growth defects and is generated during the growth of a hexagonally ordered overlayer (Al2O3) on a body-centered cubic (110) substrate (NiAl).     

超声/紫外/O3/H2O2处理去除水中DDT的研究

[目的]研究超声/紫外/O3/H2O2处理去除水中DDT的效果,为建立新的去除水中DDTs的AOPs技术提供参考。[方法]配制一定浓度的DDT水溶液,分别采用超声、紫外、O3/H2O2、超声/紫外和超声/紫外/O3/H2O2组合处理,并用超声/紫外/O3/H2O2组合处理北江佛山段水样,用GC-EDC方法检测DDT含量变化,比较各处理方法的DDT去除率。[结果]水中DDT去除率分别为:超声波处理为45%～56%、紫外光处理近70%、超声/紫外联合处理超过80%、O3/H2 O2处理为28%～32%、超声/紫外/O3/H2 O2处理为91%,而北江水样DDT去除率达到85%。[结论]超声/紫外/O3/H2O2联合处理可有效去除水中DDT。     

普安银鲫胚胎发育过程消化酶活性变化研究

采用生物化学方法测定和分析了普安银鲫(Carassius auratus)未受精卵与受精卵及胚胎发育过程中消化酶活性及其变化。结果显示,受精卵与未受精卵相比,5种酶活力均高于未受精卵,未受精卵与受精卵消化酶活力顺序均为:淀粉酶>胰蛋白酶>脂肪酶>胃蛋白酶>纤维素酶。胚胎发育不同时期,5种消化酶各自出现不同的变化模式,淀粉酶活力呈波浪式下降趋势,胰蛋白酶、脂肪酶、胃蛋白酶、纤维素酶活力均呈升高趋势。     

三层交换与VLAN技术在校园网中的应用

三层交换是路由功能和二层交换的技术集成，基于三层交换的VLAN划分使网络以予网内线速交换和子网间的线速路由来达到线速通信。由于这种特殊性，三层交换和VLAN技术已成为中小型校园网的有效解决方案。在简述这种解决方案优点的基础上，通过组建校园网的实例，探讨了利用三层交换和VLAN技术组建一个可伸缩智能化校园网的过程，表明这种技术对提高校园网络安全性和校园网络管理性能有积极作用。图1参6     

以2b-RAD技术构建凡纳滨对虾遗传连锁图谱及生长性状QTL定位

【目的】构建凡纳滨对虾高密度遗传连锁图谱,并对生长相关性状进行QTL定位,筛选出生长性状相关候选基因,为后续开展凡纳滨对虾分子标记辅助育种、生长相关功能基因精细定位研究等提供理论依据。【方法】以耐低盐选育凡纳滨对虾为父本,厄瓜多尔野生凡纳滨对虾为母本,单尾交配,以2个亲本及150个F₁代个体为作图群体,通过2b-RAD测序挖掘SNP分子标记并构建遗传连锁图谱;结合生长性状表型数据,使用MapQTL 6.0在构建的遗传连锁图谱上对体质量、全长、体长、头胸甲长、头胸甲宽、头胸甲高等13个生长相关性状进行QTL定位。筛选QTL区间SNP分子标记附近的基因,经GO功能注释及KEGG信号通路富集分析,挖掘生长相关候选基因;并采用实时荧光定量PCR检测候选基因在凡纳滨对虾不同组织及不同群体间的表达情况。【结果】构建的凡纳滨对虾遗传连锁图谱包括3136个SNPs标记,分布在44个连锁群上;总图谱全长为5430.54 cM,平均图距为1.73 cM。生长性状QTL定位共产生79个生长性状相关QTLs,LOD范围为3.00~11.04,可解释的表型变异范围为9.0%~28.8%。根据GO功能注释及KEGG信号通路富集分析结果,最终筛选出4个生长相关候选基因（TOB2、CRAT、CCT6、KLF4）。4个候选基因在凡纳滨对虾各组织中均普遍表达,且CCT6、KLF4和TOB2基因在耐低盐选育家系群体中的相对表达量均高于常规的凡纳滨对虾群体,其中CCT6基因表达差异达显著水平（P<0.05）。【结论】基于2b-RAD技术构建的凡纳滨对虾遗传连锁图谱鉴定出79个与生长性状相关的QTLs,并筛选出4个与凡纳滨对虾生长性状相关的候选基因（CCT6、KLF4、TOB2和CRAT）。可见,以2b-RAD技术结合QTL定位能高效、快捷挖掘出凡纳滨对虾生长性状相关候选基因,为开展分子标记辅助育种、生长相关功能基因精细定位研究等提供技术支持。     

2BM-2／3型免耕播种机的研制

２ＢＭ-２／３型免耕播种机与小四轮拖拉机相配套，能够一次完成扒秸破茬松土、播种施肥、覆土镇压等作业，播种沟低于地面５ｃｍ左右，还能起到探墒播种的作用。也适应于硬茬地和翻耕地，对麦茬地按时间复播玉米、大豆、向日葵等作物也有重要意义。     

生物发酵床对育肥猪舍氨气和硫化氢浓度季节动态的影响

为了研究生物发酵床对育肥猪舍空气环境的影响,2010年1月10日至2010年12月10日在定西某猪舍进行气体采集测定试验,对利用生物发酵床技术(试验组)和普通水泥地面饲养(对照组)圈舍内氨气(NH3)和硫化氢(H2s)2种气体的季节浓度变化进行了研究.结果表明:生物发酵床技术组冬季猪舍环境温度显著高于普通水泥地面饲养组...