A preliminary study on Typhoon Tim induced resonance at Hualien Harbor,Taiwan

New analysis of wave records at Hualien Harbor during Typhoon Tim in 1994 reveals that for certain wave periods, the ratios of measured wave heights among three available wave stations inside the harbor are unique and roughly remain the same during the severest period of resonance. Since there is no incident infragravity wave (period from 80 to 220 s) information at offshore boundaries, these unique ratios become the surrogate of background truth for checking the performance of numerical simulations. A new simulation effort using a large (45 × 17 km) modeling domain, high-resolution (20 × 20 m) grid and the RIDE wave transformation model were conducted to simulate the observed responses. Comparison of the modeling results with the observations showed reasonable agreement. Additional model studies using ideal bathymetries with the same grid domain and resolution were also conducted to help interpret the prototype modeling results. The effects of two types of commonly used remedies were first examined by using the ideal bathymetry, and then, the prototype bathymetry. The results demonstrated that a single 1-km long, shore-parallel breakwater could significantly reduce the resonance. The results of using three shore-parallel breakwaters, however, are no better. More studies to identify the optimum design associated with the shore-parallel breakwater (location, length, etc.) are necessary for the optimum reduction of resonance at Hualien Harbor.     

Behavioral effects of titanium dioxide nanoparticles on larval zebrafish (Danio rerio)

In this study, zebrafish embryos were exposed to titanium dioxide nanoparticles (TiO2 NPs at 0.1, 0.5, 1, 5, 10 mg/L or control) from fertilization to free swimming stage. Hatchability, survival, and malformation rate were not affected by TiO2 NPs at these exposure levels. However, larval swimming parameters, including average and maximum velocity and activity level were significantly affected by TiO2 NPs. Co-exposure to either the glutathione precursor, N-acetylcysteine (NAC), or the glutathione synthesis inhibitor, buthionine sulfoximine (BSO), did not significantly alter the behavioral effects resulting from TiO2 NPs, suggesting that other factor(s) besides oxidative stress may contribute to the behavioral toxicity of TiO2 NPs. Our study also demonstrated that the behavioral endpoints were more sensitive than the others (e.g., hatchability and survival) to detect toxicity of TiO2 NPs on developing fish.     

Landslide blockage length estimation for the man-made linear structures

The landslide blockage length along a man-made linear structure, the Alishan railway, is analyzed herein. The Alishan railway runs from Chiayi City to the Alishan scenic area. Numerous landslide and debris flow disasters have blocked the railway since it began operations in 1911. In this study, features of landslides are interpreted from Spot 5 images along the Alishan railway. The results show that larger landslides along the railway exhibit a power-law distribution in frequency-area analysis. The railway blockage length by landslide and its frequency can be linearized by plotting it in a log scale for a blockage length over 0.02?km. The characteristics may be attributed to the fact that the landslide magnitude for its area and volume versus frequency exhibits a power-law distribution. It may thus be possible to estimate the blockage length of linear structures (e.g., railway and expressway) by landslides using the power-law distribution.     

Effects of body force on transient poroelastic consolidation due to groundwater pumping

By applying linear poro-elasticity theory, the body force effect on steady soil consolidation, i.e., settlement, caused by constant water table depression due to groundwater pumping was investigated. The result shows that when the soil is soft or thick, or both, neglecting the body force effect can lead to severe underestimation of soil displacement and incremental effective stress. However, the transient response of soil consolidation was not analyzed. In addition, the water table depression due to groundwater pumping in fact varies with time. In this study, the body force effect on transient consolidation of soil subjected to variable water table depression is further examined. A poroelastic consolidation numerical model is developed herein to conduct this examination.     

Estimating the economic impacts of climate change on infectious diseases: a case study on dengue fever in Taiwan

Researchers of climate change have suggested that climate change and variability has a significant influence on the epidemiology of infectious diseases, particularly vector-borne diseases. The purpose of this study is to explore how climate conditions and the dengue fever epidemic in Taiwan are related and to estimate the economic impact of climate change on infectious diseases. To achieve these objectives, two different methods, one involving the Panel data model and the other the Contingent Valuation Method (CVM), are applied in this study. At first, we use the Panel data model to assess the relationship between climate conditions and the number of people infected by dengue fever during the period from January 2000 to February 2006 in 308 cities and townships in the Taiwan. The results of the empirical estimation indicate that climate conditions have an increasingly significant impact on the probability of people being infected by dengue fever. The probability of being infected by dengue fever due to climate change is then calculated and is found to range from 12% to 43% to 87% which represent low, mid, and high probabilities of infection caused by climate change when the temperature is increased by 1.8°C. The respondent’s willingness to pay (WTP) is also investigated in the survey using the single-bounded dichotomous choice (SBDC) approach, and the results show that people would pay NT$724, NT$3,223 and NT$5,114 per year in order to avoid the increased probabilities of 12%, 43%, and 87%, respectively, of their being infected with dengue fever.     

STUDIES ON THE GEPPELLA(CHLOROPHYTA) OF XISHA ISLANDS,SOUTH CHINA SEA

The genus Geppellais a small group of tropical and subtropical algae.It was establishedby Boergesen in 1940 on the basis of its uncalciferous frond and its characteristic of annularattachments of the filaments,with G.mortensenii Boergesen as the type of the genus.Sincethen four more species have been described,namely,G.decussata Dawson(1959),G.echino-caulos Cribb(1960),G.yaeyamense Tanaka(1963),and G.japonica Tanaka et Itono(1977).The species G.decussata was reported by Dawson from Isla San Francisco(Gulf of California)and the Marshall Islands,central Pacific,and later removed by Tanaka and Itono(1977)from the genus Geppella because of the absence of blade and of annular attachments of     

钝顶螺旋藻藻胆体的简易制备及褐藻酸钠对其稳定性的保护作用

以钝顶螺旋藻为材料，用改进的简易方法分离得到完整藻胆体，室温最大荧光发射峰位于６８１ｎｍ，加水解离后最大荧光发射蓝移到６５５ｎｍ，Ｆ６８０有两个峰，分别位于６３８ｎｍ和６５０ｎｍ，从而表明藻胆是完整的。用４３６ｎｍ波长激发，没有出现Ｃｈｌａ的特征荧光峰，Ｆ７２０的荧光激发光谱，也没有出现Ｃｈｌａ的峰，表明藻胆体溶液中不含Ｃｈｌａ。在藻胆体溶液中加入１％的褐藻酸钠，室温下保存１５ｄ后，光谱特性没有变     

红藻真江篱质粒的发现

于1992年4月一1993年4月，用液氮研磨-苯酚／氯仿抽提-异丙醇沉淀的方法提取青岛沿海产紫菜、真江蓠、龙须菜、海膜4种红藻的总DNA；利用Hoechst－CsCl密度梯度起离心法将叶绿体DNA与核DNA分开。对抽取的叶绿体DNA梯度组分电泳结果表明，真江蓠样品出现质粒的电泳条带。以透射电镜观察到闭会环状DNA图像（周长平均值为4.3×10－7m，约为1．3kb）；分子杂交结果显示，真江蓠质位与其叶绿体DNA之间没有同源性，而与核DNA之间有一定同源性。