Composition,characteristics and long-term variability of the freshwater microcrustacean fauna of the Faroe Islands

ABSTRACT

Despite the accessibility of the Faroe Islands, faunistic research on their numerous lakes and ponds is quite rare. The biota of Faroese freshwaters is still underexplored, and its specific traits raise many questions. In the present survey, 32 microcrustacean species were observed, 8 of which were new to the Faroese fauna. The obtained species list shows that Cladocera species prevail over Copepoda here, which is not typical of northern territories. This fact is due to (1) the extraordinarily warm climate of the Faroe Islands compared to other areas at similar latitudes because of the heating effect of the surrounding North Atlantic Current and (2) the lack of calanoid species, which have never been found in the freshwaters of the Faroe Islands. The diachronic analysis of the species diversity and composition over the centuries of research on the archipelago showed no evidence of the impact of global climate change on the fauna.     

Anti-adipogenic effects of extracts of Ficus deitoidea var. deltoidea and var. angustifolia on 3T3-L1 adipocytes

Objective： This study examined the anti-adipogenic effects of extracts of Ficus deltoidea var. deltoidia and var. angustifolia, a natural slimming aid, on 3T3-L1 adipocytes. Methods： Methanol and water extracts of leaves of the F. deltoidea varieties were analyzed to determine their total flavonoid content （TFC） and total phenolic content （TPC）, respectively. The study was initiated by determining the maximum non-toxic dose （MNTD） of the methanol and water extracts for 3T3-L1 preadipocytes. Possible anti-adipogenic effects were then examined by treating 2-d post confluent 3T3-L1 preadipocytes with either methanol extract or water extract at MNTD and half MNTD （1/2MNTD）, after which the preadipocytces were induced to form mature adipocytes. Visualisation and quantification of lipid content in mature adipocytes were carried out through oil red O staining and measurement of optical density （OD） at 520 nm, respec- tively. Results： The TFCs of the methanol extracts were 1.36 and 1.97 g quercetin equivalents （QE）/100 g dry weight （DW）, while the TPCs of the water extracts were 5.61 and 2.73 g gallic acid equivalents （GAE）/100 g DW for var. deltoidea and var. angustilofia, respectively. The MNTDs determined for methanol and water extracts were （300.0±28.3） and （225.0±21.2） μg/ml, respectively, for var. deltoidea, while much lower MNTDs [（60.0±2.0） IJg/ml for methanol extracts and （8.0＋1.0） μg/ml for water extracts] were recorded for var. angustifolia. Studies revealed that the methanol extracts of both varieties and the water extracts of var. angustifolia at either MNTD or 1/2MNTD significantly inhibited the maturation of preadipocytes. Conclusions： The inhibition of the formation of mature adipocytes indicated that leaf extracts of F. deltoidea could have potential anti-obesity effects.     

试论高校图书馆过刊管理工作的完善

阐述了高校图书馆过刊资源的特点，分析了高校图书馆过刊管理中存在的问题，提出了完善高校图书馆过刊管理工作的建议。     

过氧化物硅烷偶联剂在玻璃纤维表面上接枝高分子链的研究

合成了（ＣＨ３Ｏ）３ＳｉＣ３Ｈ６－Ｏ－Ｏ－Ｃ（ＣＨ３）３结构的过氧化物硅烷偶联剂，用红外光谱对其结构进行了表征，用膨胀计法测定了该偶联剂引发苯乙烯单体聚合的效果，发现其引发聚合的速率远高于未使用该偶联剂的苯乙烯样品，对参与聚合的玻璃纤维表面用光学显微镜及扫描电镜证明了该偶联剂对玻璃纤维偶联，引发聚合并产生高分子链的接枝能力。     

Fine structure and phase composition of Fe-14Mn-1.2C steel:influence of a modified mixture based on refractory metals

The effect of TiO₂, ZrO₂ and Na₃AlF₆ ultrafine powders on the fine structure and the phase composition of Fe-14Mn-1.2C steel was investigated. The introduction of the ultrafine powders into the melt influenced the grain size, the quantity, and the character of distribution of nonmetallic inclusions in the railroad frogs. The microstructure of castings was improved significantly because of the refinement of the grain structure and an increase of the grain-boundary area. After the modifying mixture was introduced into the melt, either the microtwins of one or two intersecting systems or the precipitations of ε-martensite of different types, or simultaneously the microtwins and wafers of ε-martensite, were present in each grain.