Effects of temperature on feed intake,growth and oxygen consumption in adult male king crab Paralithodes camtschaticus held in captivity and fed manufactured diets

The current study investigates whether it is possible to increase the meat content of captive male king crab (Paralithodes camtschaticus) (average = 2.2 kg) by feeding manufactured diets at different temperatures (4°C, 8°C and 12°C). A 110 days trial was undertaken with groups of male king crabs held in 12 land‐based holding tanks. All crabs survival in the lowest temperature treatment, one animal died in the medium‐temperature group (8°C) and four animals in the highest temperature treatment (12°C). The results showed that feed intake increased with increasing temperature from an average of 1.0 g kg^?1 day^?1 at 4°C to 2.8 g kg^?1 day^?1 crab at 12°C. The percentage meat content was significantly higher at the final census (60.0%) compared with the initial census (37.5%) in all temperature groups, but there were no significant differences in the percentage meat content of the king crabs held in the different temperature treatments at the conclusion of the experiment. Oxygen consumption was also significantly affected by temperature and increased with increasing temperature. The results of the experiment show that the optimal temperature to maintain, and enhance, the meat content of king crab is close to 4°C.     

有机化合物的陆地和水生环境毒性的计算机预测研究

采用子结构模式识别结合5种机器学习方法(包括支持向量机、C4.5决策树、k-最近邻法、随机森林法、和朴素贝叶斯法),分别构建了有机化合物对水生和陆地环境毒性评价的两个重要生物靶标——呆鲦鱼(Fathead minnow)和蜜蜂毒性的定性分类和定量回归预测模型。所有模型均通过独立测试集验证。其中,利用支持向量机分类算法得到的分类模型对呆鲦鱼和蜜蜂毒性测试集的整体预测准确度分别达到95.9%和95.0%。采用支持向量机回归算法得到的回归模型,对呆鲦鱼和蜜蜂毒性测试集的预测相关系数的平方(R2)分别达到0.878和0.663。最后,通过信息熵分析的方法,确定了一批能够代表性地表征呆鲦鱼和蜜蜂毒性的子结构模式,包括1,2-二酚、二烷基硫醚、二芳香醚和磷酸衍生物等。提出的方法为有毒化学品的生态风险评价提供了一种非常好的评价策略和可靠的工具。     

Gousiekte in African buffalo (Syncerus caffer)

Three African buffalo (Syncerus caffer) that died after capture and translocation from Mutirikwe Recreational Park in southern Zimbabwe showed macroscopic and microscopic lesions of cardiomyopathy compatible with a diagnosis of gousiekte. The buffalo had had access to Pavetta schumanniana, a plant that is known to cause gousiekte. Death was attributed to cardiac failure as a result of previous consumption of the plant, exacerbated by the stress of translocation.     

Sediments in urban river basins: a review of sediment–contaminant dynamics in an environmental system conditioned by human activities

Background, aim and scope  Over 50% of the global population live in urban centres and, therefore, an understanding of the processes acting upon urban systems is a global issue. The nature of human-made, often impervious, land surfaces and heavily engineered waterways results in hydrological and sedimentological systems in urbanised basins which contrast significantly to those within more natural (i.e. pristine, forested, agricultural) aquatic systems. In addition, the abundance of contamination sources in urban systems results in chemical pressures often manifested as high pollution concentrations or loadings, which in turn have detrimental impacts on human and ecosystem health. These lead to management and sustainability issues not generally encountered in more natural environments. The purpose of this review is to provide a state-of-the-art assessment of sediment sources, pathways and storage within urban river systems, to consider sediment management within urban systems and river basins, and examine the role of local and global environmental changes on sediment processes and management. Inevitably, much of the sediment that is transported within urbanised basins is contaminated, so this review also considers sediment–contaminant sources and interactions. Conclusions and recommendations  We reach a number of conclusions and recommendations for future research. There is a need for better sampling and monitoring of sediment and sediment-associated contaminant fluxes and cycling in urban river channels and basins. This should include better techniques and studies to identify sources and transfers of road-deposited sediment (RDS), airborne particulate matter and sediments in the river system. Greater interdisciplinary research, combining sedimentologists, hydrologists, urban planners, urban archaeologists, chemists and biologists, is needed. More attention needs to focus on upscaling and connecting urban areas to the rest of the river basin, both upstream and downstream. Finally, there is a need to balance multiple needs (urban population, water resources) with likely trends in both urban development and global environmental change.     

Changes in the contents of oleoresin and pungent bioactive principles of Jamaican ginger (Zingiber officinale Roscoe.) during maturation

Changes in the yields of the oleoresin and content of pungent bioactive principles: [6], [8], [10] gingerols and [6] shogaol of Jamaican ginger ( Zingiber officinale) were investigated during different stages of maturity (7-9 months). Ethanolic oleoresin extracts were prepared (95%, w/w) by cold maceration of dried ginger powder, and their percentage yields were calculated (w/w). The pungent bioactive principles in the ginger oleoresin were extracted with methanol and quantitatively analyzed by high performance liquid chromatography (HPLC). Ginger harvested at 8 months from Bourbon, Portland had the highest oleoresin yield (8.46 +/- 0.46%). [6] Gingerol was found to be the most abundant pungent bioactive principle in all the oleoresin samples investigated, with the 9 months sample from Bourbon, Portland containing the highest level (28.94 +/- 0.39%). The content of [6] gingerols was also found to be consistently high (7-9 months) in oleoresin samples from Johnson Mountain, St. Thomas (15.12 +/- 0.39 to 16.02 +/- 0.95%). The results suggest that Bourbon in Portland may be the most ideal location for cultivating ginger for high yields and quality, however, Johnson Mountain in St. Thomas could prove to be the least restrictive location, allowing for harvesting of good quality material throughout the maturity period (7-9 months).