皱纹盘鲍人工诱导雌核发育精子遗传失活的初步研究

用波长253．7nm，光照强度1．108mW/cm^2的不同剂量紫外线照射皱纹盘鲍（Haliotis discus hannai Ino)精子，然后与皱纹盘鲍的正常卵受精。在0－120s的照射范围内，受精作用都仍能正常发生，从早期胚胎存活率上可观察到“Hertwig”效应的存在，单倍体和非整倍体胚胎在孵化前死亡。在150000个精子／cm^2的条件下，精液厚度5mm左右，经70s以上紫外线照射后，精子染色体可完全失活。     

皱纹盘鲍对河流弧菌-Ⅱ苗免疫的研究

于１９９３－１９９５年，用免疫法防治皱纹盘鲍脓疱病，河流弧菌－ＩＩ分离自大连水产养殖公司，太平洋海珍品养殖公司的患脓疱病的皱纹盘鲍；健康皱纹盘鲍，由大连水产养殖公司石庙苗种厂提供，鲍血淋巴细胞的体外培养吞噬实验，取健康皱纹盘鲍的血淋巴与肝素和菌液铵一定比例混合后，置湿盒内３７℃培养３０ｍｉｎ，取一滴涂片，吕氏液染色后观察，用该病原菌制做菌苗，大量扩增病原菌，用０．１％－１．０％的甲醛洗下菌苔，处理     

用6－甲氨基嘌呤诱导贻贝四倍体胚胎

在滤过海水中以４×１０（－４）ｍｏｌ·Ｌ（－１）６－甲氨基Ｃ嘌呤（６－ＤＭＡＰ）处理贻贝Ｍｙｔｉｌｕｓｅｄｕｌｉｓ受精卵或胚胎，受精激活后５０或１２０ｍｉｎ处理２０—３０ｍｉｎ，分别抑制第一或第二次有丝分裂，以诱导四倍体胚胎。顶荧光显微观察表明，６－ＤＭＡＰ有效地抑制了第一和第二次卵裂。它使细胞核染色质分散，抑制了原核的移动和染色体的分离，并防碍卵裂沟和极叶的形成，从而诱导出四倍体胚胎。对第一次卵裂的抑制产生８２．８％的四倍体胚胎；第二次卵裂抑制产生５８．６％的四倍体胚胎。由于６－ＤＭＡＰ如此有效，而且价格便宜以及对人体无害，与沿用的化学诱导剂细胞松弛素Ｃ．Ｂ．相比，它应该可以成为双壳类软体动物染色体操作研究的理想化学诱导剂之一。     

药物诱导虾夷扇贝四倍体的初步研究

1992－2000年采用细胞松驰素B（CB）、秋水仙素、6－二甲基氨基嘌呤（6－DMAP）以及咖啡因等药物抑制虾夷扇贝第一极体（PB1）释放、PB1和第二极体（PB2）释放以及抑制第一次卵裂等方法，诱导虾夷扇贝四倍体。结果表明，CB、6－MDAP和秋水仙素抑制扇贝第一次卵裂秀发四倍体的比例低于25％；采用CB抑制PB1可有效地诱导产生四倍体，从授精后42min提前到15－22min开始处理，抑制PB1的放出有助于提高四倍体的比例，在12℃，处理开始和终止时间分别在授精后20－22min t 62-67min时（即PB2始出现时），面盘幼虫四倍体率最高，为56．5％。采用CB和咖啡因共同抑制PB1放出，未见四倍体比例有升高现象。四倍体处理组发育至面盘幼虫时间比对照组晚48h左右，处理组在受精后10d时水中仍有少量浮游的、染色体数目在21－28条之间的非整倍体畸形担轮幼虫。     

6-DMAP诱导太平洋牡蛎三倍体——4.四倍体现象的研究

１９９６～１９９７年,在进行６－二甲基氨基嘌呤（６－ＤＭＡＰ）诱导太平洋牡蛎产生三倍体的实验过程中,发现一定数量的四倍体。解剖法获取精卵,人工授精。染色体倍性鉴别采用染色体计数法。（１）三因素四水平Ｌ１６（４５）正交设计。试验平行重复２次。最高四倍体诱导率为４０．０±０．０％。太平洋牡蛎四倍体各诱导因素的最优水平组合：当精卵混合２０ｍｉｎ时,将受精卵浸泡在含６－ＤＭＡＰ４５０μｍｏｌＬ－１的海水中１０ｍｉｎ;决定四倍体产生的三因素的主次顺序：６－ＤＭＡＰ浓度→诱导时机→诱导持续时间。（２）三因素三水平Ｌ９（３４）正交设计。试验平行重复３次。最高四倍体诱导率为９．６±４．９％。诱导太平洋牡蛎四倍体各因素的最优水平组合：当５０％受精卵出现第一极体时,将受精卵浸泡在含６－ＤＭＡＰ４５０μｍｏｌＬ－１的海水中１５ｍｉｎ;决定四倍体产生的三因素的主次顺序：诱导时机→６－ＤＭＡＰ浓度→诱导持续时间。     

栉孔扇贝四倍体的研究Ⅰ:细胞松驰素B诱导

利用细胞松驰素Ｂ抑制栉孔扇贝Ｃｈｌａｍｙｓ（Ａｚｕｍａｐｅｃｔｅｎ）ｆａｒｒｅｒｉ受精卵的第一极体的放出和第一次有丝分裂获得四倍体。在２０℃条件下，卵子受精后１０ｍｉｎ，０．５μｇ／ｍｌ的ＣＢ持续处理１０ｍｉｎ、２０ｍｉｎ抑制第一极体排出，结果三倍体率和四倍体率分别为３８．３８％、３９．７５％和２８．４２％、３０．２４％；在２０℃条件下，卵子受精后１ｈ，０．５μｇ／ｍｌ的ＣＢ持续处理１０、１５、２０、２５ｍｉｎ抑制第一次有丝分裂，结果四倍体率分别为２１．３６％、２７．５７％、２８．４１％、２９．３５％。结合处理后幼虫的Ｄ形率，在抑制第一极体放出和第一次卵裂中，ＣＢ处理持续１０ｍｉｎ均为最好     

用6—甲氨基嘌呤诱导贻贝四倍体胚胎

在滤过海水中以４×１０＾－４ｍｏｌ·Ｌ＾－１６－甲氨基Ｃ嘌呤（６－ＤＭＡＰ）处理贻贝Ｍｙｔｉｌｕｓ ｅｄｕｌｉｓ受精卵或胚胎，受精激活后５０或１２０ｍｉｎ处理２０－３０ｍｉｎ，分别抑制第一或第二次有丝分裂，以诱导四倍体胚胎。顶荧光显微观察表明，６－ＤＭＡＰ有效地抑制了第一和第二次卵裂。它使细胞核染色质分散，抑制了原核的移动和染色体的分离，并防碍卵裂沟和极叶的形成，从而诱导出四倍体胚胎。对第一次卵裂     

热休克诱导斑马鱼异源三倍体的研究

于１９９７年５月在广东省珠海市集斑马鱼和豹纹斑马鱼,采用热休克方法研究阻止第三极体排放诱导异源三倍体斑马鱼的适宜条件。按正交实验方案组合诱导参数,结果表明：在卵受精后２ｍｉｎ,采用３９℃持续处理２ｍｉｎ,三倍化率可达５３．８％,原肠期相对存活率为９１．０％,尾芽期相对存活率为９１％,孵化期相对存活率为９１．１％。本研究分析了热休克处理的参数与三倍体出现率和胚胎相对存活率的关系,并得出诱导参数中起始     

皱纹盘鲍对氯霉素的通透性吸收与扩散

在海水溶液中的氯霉素分子可以越过皱纹盘鲍Ｈａｌｉｏｔｉｓ ｄｉｓｃｕｓ ｈａｎｎａｉ Ｉｎｏ的体表结构进入其血淋巴液中。鲍血淋巴液中氯霉素的浓度与药浴液的氯霉素浓度，温度均呈线性关系，药浴时间的效应表现的Ｓ形逼近曲线。在２０℃的海水中，鲍血淋巴液中的氯霉素向体外扩散的半衰期为４２ｍｉｎ。     

几种诱导物质对皱纹盘鲍幼虫变态的相互作用

本文研究用不同浓度的氯化钾（ＫＣｌ）、γ－氨基丁酸（ＧＡＢＡ）和足粘液相结合对皱纹盘鲍幼虫变态的影响，从中找出皱纹盘鲍幼虫诱导变态的最佳条件，为人工育苗提供科学依据。     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification

An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.     

A Review of Some Environmental Issues Affecting Marine Mining

This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.     

Increased Particle Fluxes at the INDEX Site Attributable to Simulated Benthic Disturbance

Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.     

Determination of In Situ Sediment Shear Strength from Advanced Piston Corer Pullout Forces

The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.