Breaking the ice: the introduction of biofouling organisms to Antarctica on vessel hulls

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Historical changes in bivalve growth rates indicate ecological consequences of human occupation in estuaries

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Selecting and ranking areas for conservation of Aegla (Crustacea: Decapoda: Anomura) in southern South America integrating biogeography,phylogeny and assessments of extinction risk

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Detecting the undetectable: Characterization,optimization, and validation of an eDNA detection assay for the federally endangered dwarf wedgemussel,Alasmidonta heterodon (Bivalvia: Unionoida)

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Conservation of freshwater wildlife in Hong Kong: A genetic perspective

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Comparison of food availability and performances of first-feeding alevins through spring with the occurrence of a flood

Climate change will increase the temperature of rivers and will lead to more extreme events, such as floods. Temperature increases and floods will likely alter the phenology of freshwater species differently and have the potential to significantly disturb prey–predator interactions. In spring, an increase in temperature triggers an increase in primary production and controls the timing of the emergence in brown trout (Salmo trutta L.). Hydrology regulates the abundance of invertebrates, which are the main food source for newborn alevins. As such, climate change may desynchronise the relationship between fish emergence and invertebrate production, resulting in a negative impact on the performance of newly emerged alevins. In the present study, we quantified the abundance of invertebrates and the performance (survival and growth) of newborn alevins in early spring (March) compared to late spring (April/May) in 8 enclosures in a semi-natural channel. In addition, we simulated a flood in 4 enclosures in late spring. Our results revealed that survival and growth of alevins in early spring were limited due to low invertebrate abundance. In late spring, there was a decrease in the survival of alevins placed in the flooded enclosures, likely due to the reduction of food availability. However, the growth of survivors increased, probably because of the increase in the abundance of Chironomidae after the flood and a reduced competition between congeners. Our results demonstrate that when emergence and flooding happen simultaneously, they can limit resources which will impact the survival and growth of young salmonids in running waters.     

Antitumor Profile of Carbon-Bridged Steroids (CBS) and Triterpenoids

This review focuses on the rare group of carbon-bridged steroids (CBS) and triterpenoids found in various natural sources such as green, yellow-green, and red algae, marine sponges, soft corals, ascidians, starfish, and other marine invertebrates. In addition, this group of rare lipids is found in amoebas, fungi, fungal endophytes, and plants. For convenience, the presented CBS and triterpenoids are divided into four groups, which include: (a) CBS and triterpenoids containing a cyclopropane group; (b) CBS and triterpenoids with cyclopropane ring in the side chain; (c) CBS and triterpenoids containing a cyclobutane group; (d) CBS and triterpenoids containing cyclopentane, cyclohexane or cycloheptane moieties. For the comparative characterization of the antitumor profile, we have added several semi- and synthetic CBS and triterpenoids, with various additional rings, to identify possible promising sources for pharmacologists and the pharmaceutical industry. About 300 CBS and triterpenoids are presented in this review, which demonstrate a wide range of biological activities, but the most pronounced antitumor profile. The review summarizes biological activities both determined experimentally and estimated using the well-known PASS software. According to the data obtained, two-thirds of CBS and triterpenoids show moderate activity levels with a confidence level of 70 to 90%; however, one third of these lipids demonstrate strong antitumor activity with a confidence level exceeding 90%. Several CBS and triterpenoids, from different lipid groups, demonstrate selective action on different types of tumor cells such as renal cancer, sarcoma, pancreatic cancer, prostate cancer, lymphocytic leukemia, myeloid leukemia, liver cancer, and genitourinary cancer with varying degrees of confidence. In addition, the review presents graphical images of the antitumor profile of both individual CBS and triterpenoids groups and individual compounds.     

淮河流域贾鲁河栖息地完整性评价分析

运用多指标综合评价体系,评价了贾鲁河9个河流断面的栖息地质量状况,分析了栖息地综合指数(HI)与水质理化指标、底栖动物的相关关系,探讨了栖息地质量状况影响底栖动物分布的主要途径。结果表明,贾鲁河9个河段中,有超过50%的河段处于不健康状态;栖息地质量与水质无显著相关性,但与底栖动物生物量、B-IBI指数、Goodnight-Whitley指数、Shannon-Wiener多样性指数均显著相关(P<0.05);栖息地主要通过河道内生境变化与河滨带土地利用变化影响贾鲁河底栖动物的分布特征,其中底质类型和城镇土地利用强度是影响底栖动物分布的两大因素。