Studies on early development of Nibea miichthioides

本文对状黄姑鱼的胚胎和仔、稚鱼各发育阶段的形态特征进行了描述。绝状黄姑鱼的受精卵为圆球形浮性卵，无色透明。在水温20~23℃，盐度26~30的条件下，经24H35MIn陆续孵出仔鱼。胚胎发育分为26期。初孵仔鱼至孵化后4日龄为仔鱼前期；孵化后5~22日龄为仔鱼后期；孵化后23~32日龄为雅鱼期；孵化后33日龄进入幼鱼早期。仔、稚鱼培育水温18~28C，盐度20~30。仔鱼2日龄稍开口，3~4日龄为混合营养阶段，是仔鱼的主要危险期。The morphological characteristics of early development of Nibea miIYhthioides Chu, Lo &Wu are described.The fertilized egg is spherical in shape,transparent and buoyant' The lar-vae began hatching 24 h and 35 min after fertilization at water temperatures of 20～23℃ andsalinities of 26～30.Embrjonic development can be devided into 26 stages.The prelarvalstage developed from newly hatched larva of 4 days after hatching,the postlarval stage devel-oped,during 5～22d after hatching;the juvenile stage developed,from 23 to 32d after hatch。ing.The juvenile reached the early young stage 33d after hatching.The larvae and juvenileswere reared at water temperatures of 18～28℃ and salinities of 20～30.The 2d larval slightly opened.The mixed endogenous and exogenous nutrition occurred in 3～4d after hatching,or rather the most dangerous period.福建省自然科学基金!C9600

A Study On Feeding Behavior Ecology of Nibea Miichthicides At Eearly Stages

本文描述了(鱼免)状黄姑鱼早期发育阶段仔、稚鱼的摄食模式。前期仔鱼主要以“S-攻击型”模式摄食,辅以“前冲甩头”姿态摄食;后期仔鱼以“l-攻击型”模式摄食。稚鱼以“咬食攻击型”模式摄食。文中对上述行为的生态学意义也进行了讨论,并探讨了该研究在苗种生产中的指导意义。This paper studied the main modes of feeding behavior of the early life stages of Nibea miichthicides.There were four types of feeding behavior in the early life stages: (1)"S - posture attack"; (2)Struck at the prey with head swimming; (3)"L -posture attack" and (4)"Bitting attack".The ecological and practical significances of feeding behavior were discussed also.福建省自然科学基金;项目编号为C9600

INDUCED OVULATION AND SPAWNING OFMUDSKIPPER INSIDE ARTIFICIAL NEST

报道了人工制作的陶瓷管道诱导大弹涂鱼 Boleophthalmus pectinirostris产卵的研究结果。未经激素催熟的亲鱼放入产卵池内7—12d未见产卵，经一次激素注射催熟的亲鱼放入产卵池内第3天开始交配产卵和受精，入池后5d未能产卵雌鱼的卵母细胞开始退化吸收。雌鱼不仅在管道内产卵，而且也将卵产在管道外、池底和池壁，产卵时间集中在下半夜的02：00—04：00，不同产卵池中管道的产卵率差别很大。卵子粘附在管道不同部位的数量和受精率均不相同。强迫配对的亲鱼虽有产卵，但卵子不受精。Induced ovulation and spawning of mudskipper inside artificial nests were car-ried out in this study. The results show that the females could not ovulate and spawnwithin 7-10 days without any hormonal induction of ovulation, whereas others could o-vulate and spawn 3 days after hormonal injection. Spawning usually occurred during 2:00 to 4:00 in the morning. The spawning percentages of the artificial nests laid onto dif-ferent pools varied from 1% to 55. 6%. Apart from laying eggs inside the artificialnests, the females also laid eggs on the outer surface of the artificial nests and on thebottom of the pools as well. Only about 10 - 15 percents of females could spawn,whereas most females could not spawn although they were mature. Oocytes of the nonspawning females began to degenerate 5 days after they were introduced to the spawningponds. Fertilizing rates of the mature eggs adhering onto the artificial nests varied from10% to 89 %. When both females and males were restrained inside the artificial nestswith a ratio of 1: 1 or 1: 2, the female could reluctantly spawn, but the eggs were notfertilized.福建省自然科学基金资助项目（B0010005，B9910006

Numerical Analysis of Reverse Flow in Inverted U-tube of Steam Generator Under Natural Circulation

在自然循环工况下,倒U型管蒸汽发生器(inverted U-tube steam; generator,UTSG)内有部分倒U型管会发生倒流现象,严重影响一回路系统的自然循环能力.采用计算流体力学(computational; fluid; dynamics,CFD)方法对自然循环工况下UTSG一次侧流体的流动特性进行三维数值模拟研究.结果表明:在低质量流量下,倒流集中发生在短管侧,; 而等长倒U型管中同时出现了倒流和正流的现象,这与入口腔室分配给各个倒U型管的初始质量流量有关.随着UTSG入口质量流量的增加,UTSG倒流管数减; 少;随着一次侧入口温度的升高,UTSG进出口压降为负值,压降绝对值逐渐增大,倒流管数增多.Under natural circulation condition,reverse flow occurs within some; tubes in inverted U-tube steam generator (UTSG), which can seriously; influence the capacity of natural circulation of primary loop system.In; this study,the computational fluid dynamics (CFD) method is used to; simulate the primary side, flow characteristics of UTSG under natural; circulation condition.The results show that at a low mass flow; rate,reverse flow mostly occurs at the short pipe side, while reverse; flow as well as normal flow simultaneously occur in equal length; U-tubes.This phenomenon is related to the initial mass flow rate; assigned to each inlet tube by the inlet chamber.The less the initial; mass flow rate is,the more likely the reverse flow occurs.With the; increase of the inlet mass flow rate of UTSG,the number of the reverse; flow pipes of UTSG is reduced.With the increase of the primary inlet; temperature,the pressure drop of UTSG is negative,the absolute value of; the difference of pressure increases gradually,and the number of the; reverse flow tubes increases.福建省自然科学基

Induced maturation and spawning by pheromones in female mudskipper (Boleophthalmus pectinirostris)

成熟大弹涂鱼的卵巢、精巢和储精囊稀释液中的性外激素以及缩宫素和脱氧皮质酮 (DOC)能诱导第 4时相的大弹涂鱼卵母细胞在离体培养的条件下发育成熟 ,成熟率与性外激素的种类和剂量有关 .前列腺素E1(PGE1)单独使用的效果不明显 ,但与人绒毛膜促性腺激素 (HCG)混合使用时显著提高了卵母细胞的成熟率 .以卵巢、精巢和储精囊稀释液以及PGE1分别注射雌性大弹涂鱼 ,剂量为 0 .0 1cm3/尾的卵巢液、0 .1cm3/尾的储精囊液、0 .1cm3/尾的精巢液以及剂量为 1 0 μg/尾的PGE1都有诱导卵母细胞成熟的作用 ,其中储精囊液的作用最为显著 .在人工管道中放置大弹涂鱼成熟亲鱼卵巢、精巢或储精囊的稀释液 ,有诱导异性亲鱼进入管道内的作用 ,其中以储精囊液对雌鱼的吸引作用尤为明显 .放置于陶瓷管道或海绵管道内的卵巢、精巢或储精囊稀释液都能诱导大弹涂鱼产卵 ,在陶瓷管道的产卵量和受精率显著高于海绵管道 .Maturation of the 4th phase oocytes of mudskipper was induced in vitro by pheromones in the extract of the ovary, testis and seminal vesicle,as well as oxytocini and deoxycorticosterone (DOC). Maturation rates of oocytes related to not only pheromones but also their dosa- ges. The single use of PGE 1 was not effective in induction of maturation, but the combination of prostaglandin E 1(PGE 1) with HCG had a coordinated effect in improving ovulation. Maturation of female mudskippers with the 4th stage of ovary were effectively induced by injections of the extract of the ovary at dosages of 0.01cm 3/a fish and 0.1cm 3/a fish, seminal vesicle at dosages of 0.01cm 3 /a fish and 0.1cm 3/a fish, testis at dosage of 0.1cm 3/a fish and PGE 1 at dosage of 10μg/a fish. Among the three gonadal extract, seminal vesicle one was the most effective in the induction of maturation. Compared with the controls, those artificial nests, which had the extract of the ovary, testis and seminal vesicle inside, attracted more fish to enter into. The glands' extract attracted more heterosexual mudskippers than homosexual ones to enter the nests. Especially, the extract of seminal vesicle was more effective in attracting heterosexual individuals than ovary and testis. Female mudskippers could be induced to spawn or attracted to enter nests by the extract of glands set inside the ceramic nests. Time of spawning, the number of spawned eggs and the fertilizing rates of matured eggs were related to the types of the nests.国家自然科学基金资助项目 (30 170 739) ;; 福建省自然科学基金资助项目 (B0 0 10 0 0 5

Influence of pressure on the thermal performance of the S−CO2{\rm{S}} - {\rm{C}}{{\rm{O}}_2} Brayton cycle

为了研究${\rm{S}} -; {\rm{C}}{{\rm{O}}_2}$布雷顿循环中工作温度、压力以及换热器的换热能力对系统的热效率的影响。通过计算机数值模拟的方法,建立了; ${\rm{S}} -; {\rm{C}}{{\rm{O}}_2}$闭式再压缩布雷顿循环的热力模型。在换热器换热能力一定的条件下,通过调整压缩机出口压力、压比以及换热器压; 降等参数,研究系统循环最大热效率的变化。计算结果表明,压缩机出口压力以及压比均存在最优值,当压力超过一定数值后,增大系统压力并不能提高热效率。换; 热器的压降对系统热效率影响显著,并影响系统最大热效率情况下的再压缩份额。To study the effects of the working temperatures and pressures, and heat; exchanger (HX) characteristics on the thermal efficiency of the cycle,; an ${\rm{S}} - {\rm{C}}{{\rm{O}}_2}$ recompression closed cycle model; was established using numerical simulation. By adjusting the outlet; pressure of the compressor, and the pressure ratio and pressure loss; inside the HXs, the maximum thermal efficiency of the ${\rm{S}} -; {\rm{C}}{{\rm{O}}_2}$ Brayton cycle was studied. Results show that both; pressure and pressure ratio have an optimal value. When the pressure; exceeds a certain value, the thermal efficiency of the cycle cannot be; improved by further pressure enhancement. Pressure loss significantly; affects the thermal efficiency of the cycle and,at the same time,affects; the re-compression ratio of the cycle for maximum thermal efficiency.教育部重点实验室开发基金项

地方认同视角下居民对农业文化遗产认知及保护态度——以福州茉莉花与茶文化系统为例

居民对农业文化遗产的认知态度影响其行为选择,并对农业文化遗产的保护及可持续发展具有重要意义。基于人文地理学及环境心理学领域的地方认同理论,选择历史认同、现实认同、情感认同及行为认同4个维度变量,通过问卷调查,以福州居民对全球重要农业文化遗产"福州茉莉花与茶文化系统"的认知及保护态度作为研究对象,并通过构建福州居民农业文化遗产认知及保护规律定量分析居民认知态度、保护行为与人口特征之间的关系。结果表明:(1)福州居民对茉莉花与茶文化系统的行为认同维度得分高于其他维度,且福州市民各维度得分均高于外来居民;(2)受访居民对农业文化遗产的地方认同与其年龄、受教育水平、收入水平及在福州居住时间长短的关系较为密切;(3)通过构建福州居民农业文化遗产认知及保护规律发现,福州居民对农业文化遗产的保护行为主要受其对该遗产项目认知态度的影响,与居民人口特征相关性较弱。拓展农业文化遗产领域的研究视角及方法,促进农业文化遗产地动态保护与可持续发展具有参考价值

Expression and functional studies of roundabout 4

<p>Roundabout (Robo) receptors were first identified in neurons as guidance molecules, however growing evidence suggests that they also play a role in other cells. The aim of this thesis was to characterise the expression and function of a novel endothelial specific member of this family, Robo4. This study revealed that Robo4 is expressed primarily in vessels but also differentially expressed in tumour vessels. Interestingly Robo4 was primarily located within cytoplasmic vesicles coated with clathrin, suggesting that the presence of Robo4 on the cell surface is being tightly regulated. Overexpression of Robo4 induced filopodia and pseudopodia formation and actin re-organisation into stress fibres. It co-localised with actin and tubulin suggesting an important interaction between Robo4 and the cytoskeleton. Robo4's function in endothelial cells was directly investigated using two approaches, overexpression using adenovirus and knockdown using small interfering RNA. Functional cell-based assays revealed that disrupting Robo4's level of expression negatively affects endothelial cell functions that are required during angiogenesis, such as proliferation, migration and tubulogenesis. Overexpression of a truncated version of Robo4, which lacks the C-terminus, provided clues regarding Robo4's function. The intracellular domain is critical for Robo4's localisation and its association with the cytoskeleton. It is also required for pseudopodia formation. Other findings include possible cleavage of Robo4 and Robo4 homodimerisation and heterodimerisation with Robo1. Taken together, the findings presented in this study strongly suggest a role for Robo4 in endothelial cell guidance. Cell guidance during angiogenesis is poorly understood therefore the identification of a new molecule potentially involved in this mechanism will hopefully help elucidate the process.</p

一种油浸式变压器内部检测机器人

本发明公开了一种油浸式变压器内部检测机器人，垂直推进组件包括：槽道和设置在槽道中的垂直推进器；水平推进组件包括：水平喷射泵、喷射泵连接头以及分别设置在中壳体外部的喷射口和进液口，水平喷射泵通过喷射泵连接头分别连接喷射口和进液口，其中：垂直螺旋桨推进器产生向上或向下的推力，使机器人实现上浮或下潜运动，水平喷射泵在至少一个方向上产生推力，使机器人在水平面内的前、后、左或右方向实现移动或转动。本发明的油浸式变压器内部检测机器人，能够保证机器人在变压器内部的多自由度运动的可靠性，有效避免在变压器内部空间发生卡住或缠绕的情况；结构精简合理，进一步减小机器人的体积和重量，使集成更多功能，便于维修和维护