Changes in Lake Ontario Total Phosphorus Concentrations 1976–1978

An apparent decrease in total phosphorus concentrations of approximately 4.l μgP/L has been reported recently for the spring values of 1977 and 1978 in Lake Ontario. Investigation of the loading reduction for this period independent of sedimentation factors can account for only 10% of the change. The results indicate that changes in the sedimentation rate of total phosphorus during this period offer an explanation for the majority of the change in concentration.     

Relationship of Planning and Control Systems with Strategic Choices: A Closer Look

The study finds that relative to others, firms pursuing the Prospector-like strategy (high innovation) have lower financial results uncertainty, a more long-term orientation for decision making, and more decentralized control. As well, the tightness of budgetary control is found to be negatively correlated with financial results uncertainty. Thus, we are able to reproduce in our study the result that Prospector type firms have tighter budgetary control, which many have found puzzling previously, and point to the relation between strategy and financial results uncertainty as an explanation for the result.Based on a sample of large firms in Singapore, the study also finds the impact of the 1997–1998 Asian crisis is correlated with the intensity with which the Prospector-like strategy was pursued.     

Catching up with the Americans

This paper develops an international version of the consumption-based capital asset pricing (CCAPM), which we refer to as “catching up with the Americans.” Previous CCAPM research develops the concept of “catching up with the Joneses,” where a representative economic agent exhibits higher marginal utility of consumption as a result of higher past per capita consumption in his own country. Catching up with the Americans, on the other hand, is an international habit-preference hypothesis. It extends the idea of catching up with the Joneses by stating that consumers of non-U.S. countries gain higher marginal utility of consumption as a result of higher past American consumption growth. Contrary to much of the CCAPM literature, we test this version of the model using long bond rates rather than equity returns. However, like most of the previous research on the CCAPM, the catching up with the Americans model fails to explain the relationship between consumption and asset returns.     

Using bald eagles to indicate the health of the Great Lakes' environment

The bald eagle (Haliaeetus leucocephalus) is one of the most studied birds of North America, and a great amount of natural life‐history information, including the response of various stressors on the eagles' ability to reproduce, are well known. In Michigan, the eagle has been chosen to track the trends of bioaccumulative compounds of concern across watersheds in the state. The state has been divided into major watersheds, and 20% of these are surveyed each year. A control area in northern Minnesota, Voyageurs National Park, is also sampled annually. We report here on the methods used, the preliminary results of the 1999 field season, and how differences in mercury concentrations varied over a 10‐year period. Mercury in feathers of nestling eagles declined over time only in Lakes Michigan and Huron, but have not decreased among other subpopulations in Michigan. Concentrations of polychlorinated biphenyls (PCBs) and 4,4′‐DDE in blood plasma from nestling eagles have declined over time for most subpopulations; however, they remain greater for breeding areas associated with the Great Lakes' food web. Sea eagles of the genus Haliaeetus are a good sentinel species to track trends in bioaccumulative compounds in aquatic systems.     

多变量自回归模型在三江平原井灌水稻需水量预测中的应用

应用多变量自回归模型ARV(n), 利用三江平原腹地-富锦市1985～1999年气象资料, 按水稻生育期划分6个生育阶段, 建立了井灌水稻生育期内需水量预测模型. 经模型拟合与预测, 效果良好, 可以为该地区开展节水灌溉、灌溉用水管理、合理开发利用地下水资源, 缓解地下水危机提供参考依据.     

MODELING THE TERM STRUCTURE FROM THE ON‐THE‐RUN TREASURY YIELD CURVE

We propose a new model to estimate the term structure of interest rates using observed on‐the‐run Treasury yields. The new model is an improvement over models that require a priori knowledge of the shape of the yield curve to estimate the term structure. The general form of the model is an exponential function that depends on the estimation of four parameters fit by nonlinear least squares and has straightforward interpretations. In comparing the proposed model with current yield‐curve‐smoothing models, we find that, for the data used, the proposed model does best overall in terms of pricing accuracy both in sample and out of sample. JEL classification: E43, G12     

高级控制系统提高巴西水电站性能

巴西的一个重要电力公司COPEL最近开发了一个水电站高级控制系统，这是在电力部门经受重大变革时期，提高水电竞争力的里程碑。     

Application of a multi-channel system for continuous monitoring and an early warning system.

A multi-channel continuous toxicity monitoring system developed in our laboratory, based on two-stage mini-bioreactors, was successfully implemented in the form of computer-based data acquisition. The multi-channel system consists of a series of a two-stage minibioreactor systems connected by a fiber optic probe to a luminometer, and uses genetically engineered bioluminescent bacteria for the detection of the potential toxicity from the soluble chemicals. This system can be stably and continuously operated due to the separation of the culture reactor from the test reactor and accomplish easy and long-term monitoring without system shut down by abrupt inflows of severe polluting chemicals. Four different recombinant bioluminescent bacteria were used in different channels so that the modes of the samples toxicities can be reasonably identified and evaluated based upon the response signature of each channel. The bioluminescent signatures were delivered from four channels by switching one at once, while the data is automatically logged to an IBM compatible computer. We also achieved the enhancement of the system through the manipulation of the dilution rate and the use of thermo-lux fusion strains. Finally, this system is now being implemented to a drinking water reservoir and river for remote sensing as an early warning system.     

Monitoring of human enteric viruses and coliform bacteria in waters after urban flood in Jakarta, Indonesia.

Floodwaters in Kampung Melayu village, Jakarta, Indonesia, as well as river water and consumable water (including groundwater and tap water) samples in flooded and non-flooded areas, were quantitatively analysed to assess occurrence of viruses and total coliforms and E. coli as bacterial indicators after flooding event. High numbers of enterovirus, hepatitis A virus, norovirus (G1, G2) and adenovirus were detected at high concentration in floodwaters and waters sampled from Ciliwung River which runs across metropolitan Jakarta and is used widely for agriculture and domestic purposes by poor residents. One out of three groundwater wells in the flooded area was contaminated with all viruses tested while no viruses were found in groundwater samples in non-flooded areas and tap water samples. The results revealed that human enteric viruses, especially hepatitis A virus and adenovirus, were prevalent in Jakarta, Indonesia. This study suggested that flooding posed a higher risk of viral infection to the people through contamination of drinking water sources or direct contact with floodwaters.