The effect of the administration of Solanum malacoxylon on the chick.

Replacement of the drinking water of chicks maintained on a normal mixed protein diet with an aqueous extract containing the equivalent of 5 g of the dried leaves of Solanum malacoxylon (DLSM) per 100 ml for one month produces a hypercalcaemia (23-49 per cent), hypomagnesamia (28-37 per cent), hypophosphataemia (26-34 per cent), hypouricaemia (29-34 per cent) and a decrease in plasma alkaline phosphatase activity (54-98 per cent). The ash content of the defatted, dried tibiae and the body weight of the DLSM treated chicks were also significantly lower (37-7 per cent and 17-79 per cent respectively) than the corresponding values for the untreated birds. The results obtained are similar to those reported for hypervitaminosis D3 in the chick.     

The effects of ultraviolet-B (UV-B: 290–320 nm) radiation on blister blight disease of tea (Camellia sinensis)

Sunlight is known to reduce the incidence of blister blight disease of tea, caused by Exobasidium vexans . The effects of the ultraviolet-B (UV-B: 290–320 nm) component of solar radiation on the disease and the development of E. vexans were studied in the field in Sri Lanka using UV-screening filter materials held over a commercial crop. Exclusion of UV-B radiation by Polyester, which reduces fluxes in the UV-B region by approximately 75–85%, increased both the number of translucent spots (immature sites of infection) and number of sporulating blisters (mature sites of infection), but it had little or no effect on the sporulation of the pathogen. When basidiospores were artificially inoculated on leaves, and were exposed to full or filtered solar radiation, their survival and germination increased when UV-B wavelengths were removed; significant differences were found 62 h after inoculation. However, UV-B did not affect the extension of germ tubes. This study indicates that the UV-B component of solar radiation plays an important role in the natural regulation of blister blight disease in the field.     

长吻帆蜥鱼作为生物采集器探究海洋中深层生物微塑料污染特征

海洋中深层生物作为链接海洋上层与深层食物网的媒介,对维系大洋生态系统结构和功能的稳定有着不可替代的重要作用。由于样品采集的困难性,针对中深层生物微塑料污染研究十分缺乏。长吻帆蜥鱼(Alepisaurus ferox)具有特殊的消化机制,是优秀的生物采集器。本研究利用激光红外成像光谱技术,量化分析了长吻帆蜥鱼胃中保存的中深层物种体内微塑料的丰度和理化特征。共采集中深层鱼类和头足类7种,其肠道中检测出微塑料146个,检出率85.71%,丰度为10.43 ± 12.12个/尾, 粒径为20.34~309.89 μm(47.36 μm ± 43.41 μm)。微塑料以颗粒状(59.58%)和碎片状(36.30%)为主,聚合物成分主要是丙烯酸酯共聚物(Acrylate copolymer),占比60.27%。本研究首次证明了长吻帆蜥鱼作为生物采集器开展海洋中深层生物微塑料污染研究的可行性,研究结果对解析大洋生态系统微塑料污染及其潜在生态风险具有重要意义。     

配筋混凝土砌块高层设计时应注意的几个问题

针对配筋混凝土砌块高层设计,提出砌块空腔墙的应用,注意合理设置水平配筋,配筋砌块深梁,控制底框房屋层间抗侧刚度比及高层墙体的裂缝问题.     

Proposals for a Sangay National Park in Ecuador

This paper describes the main features of the Sangay wilderness area in the Ecuadorian Andes. It is a region of great diversity with life zones ranging from tundra to subtropical rain forest. The conservation value of the area is assessed and the feasibility of protection determined. Boundaries based mainly on the limits of human interference are put forward with management proposals for its establishment as a National Park.