Seasonal variation in lysosomal destabilization in oysters,Crassostrea virginica

Lysosomal destabilization assays have been used as valuable biomarkers of pollutant exposures in a variety of bivalve and fish species. The responses of oysters, Crassostrea virginica, deployed at and native to various reference and degraded sites were evaluated for lysosomal destabilization during both summer and winter seasons. In both native and deployed oysters, lysosomal destabilization rates tended to be higher during the winter at both reference and polluted sites. There are at least two hypothetical explanations. Greater lysosomal destabilization rates may be related to physiological changes associated with mobilization of nutrient reserves during the winter and gametogenesis. However, lysosomal destabilization in deployed oysters was correlated with tissue metal concentrations. These data also support a second hypothesis that seasonal differences in physico-chemical factors (such as reduced levels of acid volatile sulfides) may increase the bioavailability of metals during the winter so that adverse effects are more pronounced.     

海洋底质图

根据第一个五年国民经济发展计划所拟定的关于扩大巴伦支海工业渔捞场的计划,在三十年代初期给苏维埃海洋地质学提供了编制底质图的任务。同时,为了支援我国的工业及保证航海的需要,也提出了控制苏联富饶的海洋资源的任务。 还在上古时代、在航海的早期,就萌发了对海底成分和特性的兴趣。我国在十八世纪、开始编制标有底质特性的原始航行图。以后,在所有国家的航行图上,通常注明底质的名称和它的颜色、或者其它特点的标记;这种底质标记的方法,目前还在采用,但它的缺     

南极沿海伯尔顿盐湖双刺镰状水蚤盐度耐性的季节变化

双刺镰状水蚤Drepanopus bispinosus为南极沿海伯尔顿盐湖(Burton lake)中的越冬种类之一,其雌性性成熟大约于每年的初冬季节,在随后8个多月的生活史中,经历了一个盐度从33(5月份)到39(11月份)的环境变化.本文报道了该水蚤雌性成体对环境盐度适应的季节差异,动物在冬季的耐低盐能力较夏季强,从冬季到夏季,动物对盐度的适应范围明显地向高盐度方向偏移,这与环境盐度对动物的驯化有关.在低盐水中,动物的呼吸率增高,且夏季大于冬季,因而进一步证实了环境盐度的变化对动物盐度适应性的影响.     

Oxidative stress in ecotoxicology: from the analysis of individual antioxidants to a more integrated approach

An integrate approach will be discussed for investigations on oxidative stress in xenobiotic toxicity. While the analysis of individual antioxidants is useful for their sensitivity and to understand the mode of action of a stressor, the integration with the analysis of the total antioxidant capacity provides a more holistic assessment of the overall biological significance of such variations. TOSC has a greater predictive value on the health condition of the organisms and allows to discriminate the different role of specific ROS in oxidative stress syndrome.     

Theoretical wind wave frequency spectra in deep water——Ⅰ. Form of spectrum

In this part ot the paper theoretical wind-wave spectra nave been derived oy (I) expressing the spectrum in series composed of exponential terms; (2) assuming that the spectrum satisfies a high order linear ordinary differential equation; (3) introducing proper parameters in the spectrum; and (4) making use of some known charateristics of wind-wave spectrum, for instance, the law governing the equilibrium range. The spectrum obtained contains the zero order moment of the spectrum m0, the peak frequency ω0 and the ratio R =ω/ω0 (ω being the mean zero-crossing frequency) as parameters. The shape of the nondimensional spectrum S(ω) = ω0S(ω)/m0(ω=ω/ω0) changes with R and theoretically reduces to a Dirac delta function δ(ω-1) when R = 1. A spectrum of simplified form is given for practical uses, in which R is replaced by a peakness factor P=S(1).     

大视野水下激光观察系统

严重受限的水下观察是无人遥控潜不器作业中的一个问题。小型二极管激励绿激光器的问世，使人科重新对作为克服某些水下观察问题手段的同步体积扫描产生了兴趣。由于所用光学装置的原因，同步扫描的局限之一在于所能达到的视野深度有限。     

渤海三维潮流数值模拟

本模型以具有自由面的三维非线性Ｎａｖｉｅｒ－Ｓｒｏｋｅｓ方程为基本方程，经σ坐标变换得到模式方程。基于过程分裂法，将三维流动中的快过程与慢过程劈开，并对每部分选用适合其物理特性和数值行为的计算格式，然后耦联求解。应用本模型详细计算了渤海的三维潮运动。其中，潮波系统模拟获得理想的结果；采用十层模式计算了Ｍ２潮流，以较高的辨率揭示了潮流的空间结构特征。最后本文给出了三维潮流预报的应用实例。