马氏珠母贝胚胎和早期幼虫冷冻的研究

0～4℃下,不同发育时期的马氏珠母贝(Pinctada martensii)胚胎和幼虫在不同浓度的DMSO抗冻保护液中放置30min后,置室温恢复,并以不同浓度的DMSO作为抗冻保护液,通过缓慢降温对不同发育时期的胚胎和早期幼虫进行超低温(-196℃)冷冻、35℃水浴快速解冻。结果表明:低温下DMSO对胚胎和早期幼虫活力影响较弱;马氏珠母贝的囊胚和担轮幼虫存活率较低。当DMSO体积分数为14%时,原肠胚的存活率为10%左右,且部分胚胎能够继续发育至D形幼虫;当DMSO体积分数为14%、16%时,解冻后的D形幼虫存活率超过49.9%,其中大部分存活48h以上。     

Temperature effects on the embryo development and hatching of the spiny lobster Sagmariasus verreauxi

Factors affecting the development of the embryos and production of larvae of the spiny lobster Sagmariasus verreauxi were investigated. Mature lobsters were collected from the fishery in New Zealand and held in captivity until they moulted, mated, and extruded eggs. For females, moulting took place in winter (July/August) and mating occurred 58–88 days later in early spring. The ovigerous females were then held at three temperatures and embryo development monitored at approximately weekly intervals. Mean times to hatch were 55, 75, and 130 days at 20°C, 17°C, and 13°C respectively. The total number of larvae that hatched from each female ranged from 0.97 to 1.4 million. The theoretical temperature at which embryo development ceases (a biological zero) for S. verreauxi, of 9.4°C, was calculated from data on the appearance of the median eye, the eyes and the chromatophores, and the time to hatch. An eye index formula was also derived to allow prediction of time to hatch at a range of temperatures using the cumulative difference between the rearing temperature and the biological zero. First instar phyllosomas from embryos reared at 20°C were significantly smaller than those from 17°C and 13°C but there was no significant difference in fitness. This study shows that hatching can be spread over a number of months, without significantly affecting larval quality, simply by manipulating holding temperature.     

冰相雨胚转化水汽密度差的实验研究

我国的降水云系多属混合云。成雨机制中固相雨胚的形成对自然降水和人工增雨都具有十分重要的意义。该文通过飞机外场催化试验指出固相雨胚的形成过程不仅转化过冷云水，还可转化冰水面饱和水汽密度差Δρ（g/m3）。为在低过冷云水含量（SLWC）（g/m3）的云中实施人工增雨提供了重要的实验依据。并将使降水形成理论日臻完善。     

用mRNA差异显示技术分析中华绒螯蟹早期发育的基因表达

用中华绒螯蟹（Eriocheir sinensis)未受精卵、受精卵、二细胞胚、囊胚、原物胚为材料，提取总RNA，分别用Oligod T12GA、GC、AC3种锚定引物合成以上5种材料的cDNA第一链，然后以此cDNA为模板用30种随机引物进行PCR扩增，琼脂糖凝胶电泳分析。得出了5个早期发育的特异表达片段。结果表明，未受精卵、受精卵、二细胞胚之间的差异不大，都表面为母型调控，囊胚期有新mRNA的转录，开始进入合子型调控。     

四种重金属对鮸状黄姑鱼胚胎和仔鱼的毒性

本文研究了汞、铜、锌和铬四种重金属对鮸状黄姑鱼（Ｎｉｂｅａ ｍｉ－ ｉｃｈｔｈｉｏｉｄｅｓ）胚胎发育和仔鱼存活的影响。结果表明;在试验浓度范围内,胚胎发育受 阻,受精卵孵化率显著低于对照组,初孵仔鱼出现不同程度的畸形,这些重金属对鮸 状黄姑鱼仔鱼的毒性强弱依次为Ｈｇ~２＋＞Ｃｕ~２＋＞Ｚｎ２＋＞Ｃｒ~６＋。根据实验数据求得四种 重金属对鮸状黄姑鱼仔鱼的２４、４８、７２和９６ｈ ＬＣ_５０值及安全浓度。     

Comparative performances of eggs and embryos of sea urchin (Paracentrotus lividus) in toxicity bioassays used for assessment of marine sediment quality

The potential toxicity of sediments from various ports was assessed by means of two different liquid-phase toxicity bioassays (acute and chronic) with embryos and eggs of sea urchin Paracentrotus lividus. Performances of embryos and eggs of P. lividus in these bioassays were compared for their interchangeable applicability in integrated sediment quality assessment. The obtained endpoints (percentages of normally developed plutei and fertilized eggs) were linked to physical and chemical properties of sediments and demonstrated dependence on sediment contamination. The endpoints in the two bioassays were strongly correlated and generally exhibited similar tendency throughout the samples. Therein, embryos demonstrated higher sensitivity to elutriate exposure, compared to eggs. It was concluded that these tests could be used interchangeably for testing toxicity of marine sediments. Preferential use of any of the bioassays can be determined by the discriminatory capacity of the test or vulnerability consideration of the test subject to the surrounding conditions.     

超级单体风暴中大冰雹增长机制的模拟研究

为调查超级单体中大冰雹的运行增长机制,使用三维冰雹分档对流云模式结合三维粒子运行增长模式,对一例超级单体风暴进行了数值模拟.实测风暴的结构如中气旋、弱回波区、前悬回波等被很好地模拟再现,显示了模式对超级单体具有良好的模拟能力.雹胚在风暴发展阶段由过冷雨滴冻结产生,主要分布在主上升气流区上部,在主上升气流区西北侧中高层也有相当数量的雹胚粒子,冰雹主要分布在主上升气流区东侧.风暴发展阶段产生的雹胚有7％～8％增长到1 cm以上,1％左右增长到2 cm以上,这些大冰雹绝大多数起源于主上升气流区北侧的高层云区,气旋性进入主上升气流区按照简单的上—下形式增长,少数大冰雹起源于主上升气流区西北侧风暴后部中高层,气旋性地沿着主上升气流区的边缘按照下—上—下形式运动增长,表明了超级单体中大冰雹存在两条增长路径.     

美洲鲥的人工繁殖及胚胎发育的研究

2007～2009年,利用深井水及设有钢架保温大棚的土池成功进行了美洲鲥(Alosa sapidissima)的亲鱼培育与人工繁殖的研究,同时观察了美洲鲥的胚胎发育过程.结果表明:2龄美洲鲥在池塘中经专池培育并采用激素+不饱和脂肪酸+维生素E投喂、水流刺激等培育措施使雌雄鱼的性腺成熟率达60％～80％.性腺成熟的亲鱼经生态调控促使产卵或人工催产繁殖,生态调控促使产卵中水温保持在16～23℃,池水始终保持流动状态,50对美洲鲥亲鱼自4月中下旬至5月底陆续产卵,共收集鱼卵9.0万粒,平均受精率10％,孵化率70％～80％;人工催产试验中,采用LHRH-A2+鱼类催产助剂、LHRH-A2+HCG+DOM+鱼类催产助剂和LHRH-A2+HCG+鱼类催产助剂3种催产剂配伍,背鳍基部两针注射法,催产率20％～100％,获卵10.57万粒,受精率0～21.5％,孵化率0～70％.美洲鲥受精卵呈卵圆形,卵膜径为(4.03±0.25)mm,根据胚胎的外形与内部主要特征,胚胎发育分为7个生理阶段30个具体发育时期,在水温(20±1)℃下,历时约71 h40 min完成整个胚胎发育过程.     

岱衢洋大黄鱼(Pseudosciaena crocea)胚胎与仔稚幼鱼发育

对养殖岱衢洋大黄鱼进行人工催产、自然产卵获得受精卵,在人工培育条件下观察了其胚胎及仔稚幼鱼发育过程。结果表明:1)岱衢洋大黄鱼受精卵呈圆球形,浮性;2)在水温23.0~24.0℃、盐度22.1条件下胚胎发育历时25.5h,主要经历了卵裂期、囊胚期、原肠胚期、神经胚期、器官形成期及孵化期等阶段;3)在水温22.0~24.0℃、盐度22.1~23.4条件下,仔鱼发育经历了前期仔鱼(0~7日龄)和后期仔鱼(8~18日龄);4)19日龄进入稚鱼前期,各鳍齐全;5)29日龄进入稚鱼后期,鳞片出现;6)36日龄以后全身被鳞,进入幼鱼期。仔稚幼鱼生长方程为TL=0.570 3 D+0.750 1(R2=0.965 8),全长和日龄呈极显著线性相关。     

旬邑冰雹云的数值模拟及累积带特征

在中国科学院大气物理研究所三维完全弹性冰雹云模式的基础上,把雨滴冻结过程作了进一步改进,增加了雨滴冻结成霰的过程.并利用改进后的模式模拟了陕西省旬邑县1999年7月17日的冰雹云个例,发现该例雹云中冰雹胚胎主要是冻滴,在雹云发展的初期阶段雹云中存在过冷雨水累积带,并且该处是雹胚产生的主要区域,雹块的增长主要通过雹与云水的碰并过程增长.对旬邑县1997～1999年14例冰雹云过程的模拟结果表明,旬邑冰雹云中冰雹胚胎以冻滴为主,绝大多数冰雹云都存在过冷雨水累积带,累积带维持时间约6 min,厚度4 km左右.