ON SOME KEY GEOLOGICAL PROBLEMS RELATED TO THE LINGLONG-JIAOJIA ORE-CENTRALIZED DISTRICT IN SHANDONG PROVINCE, CHINA

The Linglong-Jiaojia ore-centralized district is controlled by the tectonic stress field characterized by the combination of extension and strike-slip, and the dip, dip angle, pitch and pitch angle of the ore bodies are all constrained by the dynamic conditions of the tectonics. The metallotectonic series for the ore-centralized district belong to the type of a combination of extension and strike-slip and can be subdivided into four sub-series. The ore-forming process in the brittle regime can be disintegrated into two stages, i.e., the embryonic fracture stage and the megascopic fracture stage, and ore-forming process is rather common in the ore-centralized district at the former stage. Moreover, several key structural patterns and their features were discussed and a preliminary assessment about the ore-forming prospect in this district was made in the paper.     

珠江斑鱯的早期胚胎发育观察

观察了珠江斑鳠3批次受精卵的胚胎发育,描述及记录了胚胎发育各期的形态特征及所需时间。斑鳠的成熟卵子呈圆形,黄色,卵子直径为3.1~3.8 mm,吸水后最大卵径为4.0~4.2 mm,受精卵黏性很小。珠江斑鳠胚胎发育与其他硬骨鱼类基本相似,属于盘状卵裂。在水温(27.5±0.5)℃时,受精后约1 h 10 min进入胚盘形成期,受精2 h 15 min后进入卵裂期,受精后7 h 50 min,进入囊胚期,再经约13 h 45 min进入原肠期,受精后21 h15 min,胚孔封闭,当受精39 h 5 min后,心脏开始出现搏动,受精后55 h,仔鱼开始孵出。     

宽壳全海笋受精和早期胚胎发育过程的细胞学观察

用普通光镜和石蜡切片技术,系统观察了宽壳全海笋卵子在受精和早期胚胎发育过程中的外形和核相变化。结果发现,宽壳全海笋成熟未受精卵呈梨形或卵圆形,核相处于第一次成熟分裂前期,有明显的生发泡和核仁;精子为鞭毛型,全长(44.042±1.166)μm,头部呈椭圆形,前端的顶体略呈钝锥状;在水温24℃条件下,精、卵混合后,精子迅速附着于卵子表面,启动卵子发育;受精后6~9 min,生发泡逐渐萎缩、破裂,随后精子进入卵内并轻微膨胀;受精后20,30 min,受精卵先后排出第一、第二极体,完成第一次和第二次成熟分裂;成熟分裂结束后,精、卵核体积迅速膨胀,核膜重新出现,形成弥散状的雌、雄原核,雄原核形成略早于雌原核;受精后40 min左右,雌、雄原核在卵子中央以原核联合的方式结合,随后联合核的染色体共同排列在纺锤体的赤道板上,形成第一次有丝分裂的中期分裂相;随着有丝分裂的进行,染色体被纺锤丝拉向两极,结果在受精后约50 min形成2个大小不等的卵裂球,第一次卵裂结束;第二次卵裂过程与第一次卵裂基本相同,只是卵裂方向与第一次卵裂基本垂直,在受精后65~70 min,第二次卵裂完成,形成1大3小4个卵裂球。另外,实验中发现了少量的多精入卵和多极分离现象。     

驼背鲈的胚胎发育

对驼背鲈(Cromileptes altivelis)的胚胎发育过程进行了观察,描述其发育各期的形态特征及发育速度。驼背鲈成熟卵呈浮性,透明,平均卵径为810μm,油球一个。在水温25~27℃,盐度30条件下,胚胎发育时间为24 h 10 min。     

黄条鰤MSTN基因的克隆及其在早期发育中的表达特征

为解析肌肉生长抑制素(Myostatin,MSTN)基因在黄条鰤(Seriola aureovittata)生长发育过程中作用机制。本研究采用cDNA末端快速扩增法,克隆了黄条鰤MSTN基因的全长cDNA序列,采用荧光定量PCR(RT-qPCR)技术对MSTN mRNA在黄条鰤不同组织、胚胎发育过程以及仔稚幼鱼发育过程中的差异表达特征进行了研究。序列分析结果显示,MSTN基因全长cDNA为1828 bp,开放阅读框为1131 bp,编码了376个氨基酸。RT-qPCR分析表明,在检测的脑、垂体、肝脏、肌肉、脾脏、肾脏、鳃、心脏、胃、肠、头肾组织中MSTN mRNA均有表达,其在肌肉中表达量最高(P<0.05)。MSTN mRNA在胚体下包2/3时期至孵化期表达量显著升高,且在孵化期达到峰值(P<0.05)。MSTN mRNA在孵化后3天前表达量显著升高(P<0.05),在第20天降低至较低水平,25天后表达量再次显著升高,在第30天达到峰值(P<0.05)。研究结果首次揭示了MSTN基因在黄条鰤的胚胎及早期生长发育过程中发挥着重要作用,本研究为开展黄条鰤繁养殖、育种提供了理论参考。     

双棘刺尻鱼的胚胎发育和仔鱼早期发育研究

本研究报道了一种分布广泛的小型珊瑚礁鱼——双棘刺尻鱼（Centropyge bispinosa）的胚胎发育和仔鱼早期发育过程。结果表明,双棘刺尻鱼在关灯（日落）后10～20 min产出配子,其受精卵呈透明圆球状,卵直径为638.5±5.7 μm, 卵内存在单一油滴,直径为179.9±10.3 μm,油滴内部占据空间最多的是卵黄。在24.5 ℃的水温下受精后16 h 30 min孵化。初孵仔鱼体长为1 161.3±55.2 μm,大量器官尚未发育完全,无口和消化道,眼睛无色素沉淀,不具备主动游泳的能力。孵化后第1天其体长快速发育至2 241.7±54.2 μm,卵黄大部分被吸收,躯干上出现较大的色素细胞。孵化后第2天仔鱼体长发育速度减缓,增长至2 476.4±12.7 μm,但是同时重要器官如消化道、肛门发育完成,卵黄几乎全部被吸收。孵化后第3天,体长几乎没有增长,但是眼睛完成色素沉淀开始发挥功能,口部也发育完成,开始进入外源性营养阶段,有能力对猎物和捕食者做出反应。本研究为国内首次报道双棘刺尻鱼胚胎和幼体发育过程,为未来进一步开展该鱼的人工繁育工作奠定了基础。     

腺带刺沙蚕的早期发育

１９８３年７—１２月于室内进行了腺带刺沙蚕Ｎｅａｎｔｈｅｓｇｌａｎｄｉｃｉｎｃｔａ人工授精、孵化及幼体培养观察．该种沙蚕在性成熟时没有异沙蚕型出现。水温在１３．０—２９．３℃范围内，沙蚕均能完成胚胎发育和幼体发育。担轮幼虫期在膜内渡过，五刚节疣足幼虫开始摄食，七剧节疣足幼虫开始钻砂，沙蚕幼虫体节在２０节之前体节与体长呈明显的直线正相关。     

Fatty acids dynamics during embryonic development in genus Uca (Brachyura: Ocypodidae), from the mangroves of Inhaca Island,Mozambique

Variations in egg volume and fatty acid (FA) content through embryogenesis were evaluated in Uca species from Inhaca island, Mozambique. Egg volume increased 96.1%, 93.3%, 84.2%, 92.9%, 96.3%, respectively, in Uca annulipes, Uca inversa, Uca urvillei, Uca chlorophthalmus and Uca vocans (p < 0.05). Fatty acid content decreased through embryogenesis, showing its importance as fuel during embryonic development. Major fatty acids were 16:0, 18:0, 16:1n-7, 18:1n-9, 18:1n-7, 18:2n-6, 20:5n-3 and 20:4n-3. Unsaturated fatty acids (UFA) and saturated fatty acids (SFA) were used up at a similar rate for U. annulipes and U. inversa contrarily to the other three species. Within the UFA, MUFA were more consumed than PUFA for all species except U. chlorophthalmus. The high values detected for fatty acid trophic markers (essential C₁₈ and C₂₀ PUFAs) and odd-numbered fatty acid suggest that Uca species occupy medium trophic level, primarily omnivores and scavengers/detritivores consuming algae common in the intertidal habitats. The fatty acid consumption pattern during embryonic development was essentially similar between species with some variation as expected, as FA content varies within species mainly due to female feeding ecology, nutritional and physiological conditions, differential demands on resource allocation and geographic and seasonal variations in embryonic development.     

生物降解型消油剂处理燃料油对黄海胆（Glyptocidaris crenularis）胚胎发育的影响

对比研究了120#燃料油在加入消油剂前后对黄海胆胚胎生长发育的影响。将黄海胆(Glyptocidaris crenularis)胚胎分别暴露于10个不同质量浓度的120#燃料油分散液和经消油剂处理后的乳化液中,对照组为海水空白,单独消油剂海水为内置空白组,暴露30min后,测定随石油烃剂量的变化与暴露时间改变黄海胆胚胎发育及生长速率变化的规律。结果显示,试验组中黄海胆胚胎发育时间明显滞后,与暴露浓度呈正相关,且乳化液试验组滞后更为显著。石油烃暴露对黄海胆胚胎的半抑制效应浓度(EC50)随发育时间的推移逐渐降低,不同发育时期段,乳化液的EC50值均比分散液小。研究结果表明,120#燃料油暴露能影响黄海胆胚胎发育,经生物型消油剂处理后,其毒性增大。     

Three-dimensional Evolutionary Models of the Qiongxi Structures, Southwestern Sichuan Basin, China: Evidence from Seismic Interpretation and Geomorphology

Fold terminations are key features in the study of compressional fault-related folds. Such terminations could be due to loss of displacement on the thrust fault or/and forming a lateral or oblique ramp. Thus, high-quality seismic data would help unambiguously define which mechanism should be responsible for the termination of a given fault-related fold. The Qiongxi and Qiongxinan structures in the Sichuan Basin, China are examples of natural fault-propagation folds that possess a northern termination and a structural saddle between them. The folds/fault geometry and along-strike displacement variations are constrained by the industry 3-D seismic volume. We interpret that the plunge of the fold near the northern termination and the structural saddle are due to the loss of displacement along strike. The fault geometry associated with the northern termination changes from a flat-ramp at the crest of the Qiongxinan structure, where displacement is the greatest, to simply a ramp near the northern tip of the Qiongxi structure, without forming a lateral or oblique ramp. In this study, we also use the drainage pattern, embryonic structure preserved in the crest of the Qiongxinan structure and the assumption that displacement along a fault is proportional to the duration of thrusting to propose a model for the lateral propagation of the Qiongxinan and Qiongxi structures. Specifically, we suggest that the structure first initiated as an isolated fault ramp within brittle units. With increased shortening, the fault grows to link with lower detachments in weaker shale units to create a hybridized fault-propagation fold. Our model suggests a possible explanation for the lateral propagation history of the Qiongxinan and Qiongxi structures, and also provides an alternative approach to confirming the activity of the previous Pingluoba structure in the southwestern Sichuan Basin in the late Cenozoic.