Recording cerebellar neuron activities in swimming goldfish   总被引：1，自引：0，他引：1  

Noritaka Matsumoto  Masayuki Yoshida  Kazumasa Uematsu 《Fisheries Science》2007,73(3):512-521

ABSTRACT:   Neuronal activities were investigated in the cerebellum of immobilized and swimming goldfish Carassius auratus . Extracellularly recorded neural activities of the cerebellum in immobilized goldfish were characterized and classified into five types. Based on the waveforms and recording depths, these five neural activity types were estimated to originate from three identified classes of cerebellar neurons: Purkinje cells, eurydendroid cells, and granule cells. Chronic recording of cerebellar neuron activities in unrestrained goldfish was performed for more than 100 h. During the chronic recordings, a submersible amplifier attached to the goldfish head, and a multielectrode array developed for the present study were used. Neuronal activities in the cerebellum of free-swimming fish could also be classified into five types as in the immobilized condition. Firing patterns of two neurons identified as Purkinje cells and eurydendroid cells were analyzed during turning movements of the goldfish. The firing patterns of these neurons changed in relation to turning movements. Although some improvements are required, the chronic recording method developed in the present study can be applied to further investigations concerning the direct relationship between brain neural activities and certain behavior.  相似文献   

电麻醉对西伯利亚鲟幼鱼行为特性与血清离子浓度的影响   总被引：5，自引：0，他引：5  

冯广朋  庄平  章龙珍  陈宁宁  姚志峰  孟彦羽 《海洋渔业》2009,31(1)

研究了不同强度电麻醉对西伯利亚鲟幼鱼行为特性与血清离子浓度的影响。西伯利亚鲟电麻醉阶段包括部分失去平衡期、完全失去平衡期、完全麻醉期和鳃动停止期等4个时期。电麻醉时西伯利亚鲟呈现趋阳性;随着电压升高,到达各麻醉阶段时间与恢复时间逐渐缩短。西伯利亚鲟到达完全麻醉期时间在15 V、20 V、25 V、35 V组间均有显著差异,在30 V与35 V时分别仅为97.0 s和68.8 s,而恢复时间为0 s。各试验组西伯利亚鲟在电麻醉时鳃动频率均增加,而恢复阶段均降低。电麻醉对西伯利亚鲟摄食与活动状态均无显著影响。随着电压升高,钾离子与镁离子浓度先下降后上升,钙离子则先上升后下降。钠离子与氯离子浓度变化较大,均是15 V组时浓度最低,20 V时浓度最高。磷离子浓度呈现增高趋势。pH值在麻醉后降低,对照组与其余各组均有显著性差异。因此西伯利亚鲟幼鱼适宜电麻醉强度为25~30 V,电麻醉是种较好的麻醉方法,具有广泛的应用前景。  相似文献   

光照和水流对巴布亚硝水母存活时间及存活率的影响     

杨翠华  王玮  王文章 《水产科学》2011,30(9):555-558

利用人工繁殖的巴布亚硝水母30个碟状体、幼水母和成体水母,分别设立了静止和合适水流及3个光照水平,研究了不同光照和水流对其碟状体、幼水母和成体存活时间及存活率的影响。试验结果表明,光照的性质和时间决定了巴布亚硝水母碟状体和幼水母的存活率,对成体的存活时间也有显著影响。水流对碟状体有显著影响,而对幼水母和成体来说则是必须的。自然光照条件下,水母体色较浅,呈蓝色,随着卤素灯光照时间延长,体色变深,呈蓝褐色。水流还与水母的某些行为有关,在流水环境中水母喜欢聚集和逆水游动。  相似文献   

南通近岸海域水质现状与趋势分析     

方南娟  梅肖乐 《河北渔业》2012,(12):11-13

根据2005-2010年南通近岸海域的水质监测,对该区域的水质状况和趋势作出分析和评价。结果表明:影响该海域水质的主要污染因子是磷酸盐,部分站位出现无机氮超标。近岸海域水质总体变化基本稳定,部分污染物略呈上升的趋势。  相似文献   

莱州湾芙蓉岛西侧人工鱼礁建设对周边海域潮流场和水交换的影响研究#br#     

岳英洁  贺志鹏  冷星  于冬 《海洋渔业》2022,44(1):9-17

为探究人工鱼礁建设对周边海域潮流场和水交换产生的影响,基于Mike21HD潮流模型,对莱州湾芙蓉岛西侧人工鱼礁建设前后周边海域潮流场和水交换变化情况进行了数值模拟研究。结果表明,相较于鱼礁建设前,涨急时,从平面分布上,鱼礁区东西向流速呈增加趋势,南北向流速呈递减趋势;从垂向分布上,流速变化:底层>中层>表层,底层流速最大增加量8.6cm·s^-1、最大减小量4.3cm·s^-1,增加量大于1cm·s^-1的区域与鱼礁区最远距离为303m,减小量大于1cm·s^-1的区域距鱼礁区最远距离为574m。落急时,平面流速变化趋势与涨急时基本一致;垂向分布上,底层流速最大增加量7.9cm·s^-1,最大减小量3.6cm·s^-1,增加量大于1cm·s^-1的区域与鱼礁区最远距离为271m,减小量大于1cm·s^-1的区域与鱼礁区最远距离为333m。鱼礁建设后周边海域水交换率增加约0.1%。人工鱼礁投放后,只改变了礁区局部海域的水动力环境,对湾内其他海域没有影响。  相似文献   

Dual effects of reversed winter–spring temperatures on year‐to‐year variation in the recruitment of chub mackerel (Scomber japonicus)     

Hitoshi Kaneko  Takeshi Okunishi  Takashi Seto  Hiroshi Kuroda  Sachihiko Itoh  Shinya Kouketsu  Daisuke Hasegawa 《Fisheries Oceanography》2019,28(2):212-227

To clarify the effects of temperature on the recruitment of chub mackerel (Scomber japonicus) in the North Pacific, we investigated the influence of winter surface temperature (WST) on spawners at the time of maturity around the spawning grounds and the influence of ambient spring temperature on larvae using estimated temperature (ET) obtained from particle tracking experiments. We found a significant positive correlation between ET approximately 10 days following hatching and the recruitment per spawning stock biomass (RPS) after 2000. The closer (more meandering) the Kuroshio Current (KC) axis was in relation to the spawning ground, the higher (lower) the spring surface temperature and the higher (lower) RPS was in the spawning ground. In contrast, WST inside KC near the maturity/spawning ground was significantly negatively correlated with RPS. A significant negative correlation between the temperatures in winter and spring was detected in the area after 2000, when the conditions of the Pacific decadal oscillation index and the stability of the Kuroshio Extension were synchronous, indicating that KC shifted northward during this time. The reversed temperature pattern was consistent with the winter–spring movement of KC axis in the offshore direction and was correlated with the winter–spring difference in the intensity of the Aleutian low. These results suggest that the annual variation in chub mackerel recruitment after 2000 was strongly affected by the combined effects of ambient temperature because of the reversal of conditions that occurred between winter and spring around the maturity/spawning ground, which was related to the KC path.  相似文献   

水下圆形重力式网箱缆绳张力对波、流的响应特性     

刘圣聪  黄六一  倪益  程晖  赵芬芳  王欣欣  梁振林  KINOSHITA Takeshi 《水产学报》2019,43(6):1518-1526

通过模型试验研究了周长40 m、网高10 m的HDPE圆形升降式网箱沉降在水下时的缆绳张力。试验采用狄克逊准则,模型大比例尺λ=10和小比例尺λa=λd=2;网箱采用网格形式锚泊系统。试验时前主缆绳水平方向与波流夹角为0°,试验流速为0、5、10和15 cm/s,波浪周期范围1.3～2.2 s,波高范围10～30 cm。在各试验条件下对主缆绳和系框绳以及浮框绳张力进行了测试,以受力最大的缆绳为研究对象,分析了缆绳最大张力与波流因子之间的关系。结果显示:①在纯流作用下,前主缆绳受力最大;在纯波作用下,后侧主缆绳受力最大,最大张力随波高增大呈线性增长趋势,随周期变化的影响较小。②在波流作用下,高流速、低波高、高波周期条件时前主缆绳受力最大;在低流速、高波高、低波周期时后侧主缆绳受力最大;前主缆绳受水流作用影响较大,后侧主缆绳受波浪作用影响较大。③在波流作用下,各缆绳最大张力随波高、流速增大而增大,随周期增大而减小;后侧主缆绳最大张力无量纲量随波陡增大且基本呈线性增长趋势。  相似文献   

永磁式涡流缓速器制动性能影响因素敏感性分析     

赵小波  姬长英  赵国柱 《农业机械学报》2009,40(10):18-23

在分析永磁式涡流缓速器制动力矩与结构参数关系的基础上,将均匀设计和回归分析方法引入到永磁式涡流缓速器制动性能影响因素敏感性分析中。以某型号的永磁式涡流缓速器为例,建立了制动力矩随转子鼓内半径、永磁体周向长度、气隙宽度、转子鼓轴向宽度和永磁体高度5个结构参数变化的回归模型,重点讨论了结构参数间交互作用以及各结构参数对制动力矩的影响程度,基于均匀试验设计和制动性能敏感性分析的结果,采用全排列法对结构参数进行了优化。  相似文献   

牧草收割机械的现状和发展趋势   总被引：4，自引：0，他引：4  

傅美贞 《农机化研究》2009,31(6)

针对浙江省牧草畜牧业和草坪种植业的发展,分析了国内外草业收割机械的现状以及浙江省发展牧草收割机械的机遇,并提出浙江省牧草收割机械应向价格低廉、与已普及的农机具配套使用、适合小田块和丘陵地区作业的牧草收割机械方向发展,认为研制一种既能适用于牧草收割与荒地杂草的整理又能适用于绿化草坪的维护和修剪的中小型割草机是十分必要的.  相似文献   

辽西地区节水农业发展现状及对策   总被引：1，自引：0，他引：1  

张莹  孙占祥  李爽  冯良山  杨宁  刘洋  惠成章  侯志研  杨玉辉 《节水灌溉》2009,(9)

为保障粮食安全,保障农业的可持续发展,必须大力发展节水农业.通过调查辽西地区的节水农业发展现状,得出目前节水农业在农村发展中存在的问题,并提出今后节水农业的工作重点和对策.对节水农业的更好更快发展具有一定的指导意义.  相似文献