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1.
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.  相似文献   
2.
A new detection method was developed for the simultaneous quantification and genotyping of Cryptosporidium spp. in river water. Several modifications made to the US EPA Method 1623 enabled high and stable recovery of Cryptosporidium from 40 L of river water (geometric mean = 35%, standard deviation = 8.7%). Quenching probe PCR (QProbe PCR) was used to quantify the 18S rRNA gene of Cryptosporidium spp. This method could successfully detect single oocysts in a sample, and the lower quantitation limit was as low as 2.5 oocysts/sample. In addition, denaturing gradient gel electrophoresis (DGGE) followed by DNA sequencing was used to identify the genotypes. These methods were applied to detect Cryptosporidium spp. in the Koyama River, Japan. The positive ratio was 69% (11/16) with the maximum concentration of 59 oocysts/100 L. Seven genotypes including two novel ones were identified. These results showed that this detection method could provide valuable information on Cryptosporidium in river water, both in the concentration and in the genotypes, which is essential for the precise assessment of waterborne risk to human health.  相似文献   
3.
High concentrations of manganese and iron in the Saigon River are major problems for the water supply in Ho Chi Minh City (HCMC), Viet Nam. To identify their sources and leaching processes, we surveyed water quality along the Saigon River and ran batch leaching tests using soil and sediment samples. Two important leaching processes were identified: acidic leaching from acid sulfate soil (ASS) in the middle reaches of the river, and Mn dissolution and Fe reduction from sediments in the downstream reaches. Low pH caused the concurrent release of Fe and Mn from the ASS. In contrast, anoxia caused the release of Fe but not Mn from the sediments, whereas low pH facilitated Mn dissolution. Sediments are a more important source of Mn because of their higher Mn contents (10 times) and release rates (14 times) than those from ASS.  相似文献   
4.
The water volume required for daily monitoring of Cryptosporidium (which can statistically ensure an annual risk of infection below 10(-4)), was assessed by evaluating the applicability of the Poisson lognormal (PLN) distribution in microbial risk assessment. PLN showed as good a fit to the observed data as to the negative binomial distribution. From the estimated PLN distributions for the source and finished water, the efficacy of the oocyst removal by the conventional water treatment process was estimated to follow log-normal distribution (median = 3.16 log10, 95% CI = 4.27-2.05 log10). The 365 consecutive negative results of daily monitoring for 180 L of finished water were found to be statistically equivalent to the annual risk of infection below 10(-4). This research also suggested the possibility of applying a qualitative detection method, such as CC-PCR, as a routine monitoring method for the quantitative risk management.  相似文献   
5.
The Chinese banking system reform since the country's accession to the World Trade Organization has yielded remarkable success. The major listed commercial banks have improved their operational performance significantly. However, there are some signs of changes in their financial results recently. The expanding debt of non‐profitable enterprises and local governments raises a question on the achievements of the previous reform. Considering that the competition among banks will become severer with financial liberalization under slower economic growth, the banks and supervisory authorities must continue to make greater efforts towards further reform in order to improve the banks' corporate governance and the risk management system.  相似文献   
6.
The purpose of this paper is to analyze the diffusion of wind power in Japan by focusing on the value chain and the interaction between technology and markets and to contribute towards recommendations on technology policy and management. This paper proposes a framework for analyzing the early stage diffusion of wind power systems by combining the use of several approaches considering wind power system as a complex technological system. Firstly, the business system approach is used as an analytical framework by focusing on efficiency, effectiveness and development criteria. As a second approach, the technological trajectory was analyzed based on the concept of technological disequilibrium and the evolutionary patterns of innovation of wind power generation systems were analyzed and the relationship between innovations at the sub-system, modular, and system level was identified. We apply the framework to investigate why wind power diffusion has not picked up momentum in Japan.The results include the following: (1) Technological imbalances within the product system were solved by technological innovation (2) The wind power business in Japan is insufficiently effective due to organizational disequilibrium (3) The technology system has begun to evolve in the direction of micro grid systems. (4) It is important to consider the demand-pull measures for wind power generation so that Japanese institution can have a “time slot” for ”learning by doing” to catch up and accelerate diffusion of wind power generation, including institutional reform of RPS law. Also further technological development related to stabilizing unstable wind energy is required.  相似文献   
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8.
Distilled spirits producers recently voted to eliminate their voluntary ban on broadcast advertising. The ban received public support because of the high social cost associated with alcohol consumption and the belief that advertising promotes alcohol consumption and abuse. In spite of this belief, the empirical evidence indicates that advertising has no significant effect on the market demand for distilled spirits. This evidence has led many policy economists to conclude that eliminating the ban will have no effect on alcohol consumption. The purpose of this research is to show that this conclusion is incorrect because it ignores the fact that advertising restrictions may affect industry competition as well as market demand.  相似文献   
9.
In the paper, an analysis is made of the intolinkages between systems, key components and components' generic technologies in building technological competencies. The sample consists of a set of seven Japanese and four European firm in the industrial, consumer electronics and materials sectors, engaged in the field of optoelectronics. Three tyes of information-—scientific publications, US patenting and interview data—are used. The findings demonstrate the existence ofsuch interlinkages.It was possible to confirm empirically the concept of generic technologies which are the basic underbing technologies forming thefoundation of a range of key components. The generic technologia are important for all firms, irrespectives of their final product markets. Building capabilities at the upstream and over a long period allows firms to develop more high value-added systems and products. It also provides forms with the opportunity to branch into new areas.  相似文献   
10.
The paper examines the current account of 41 major airports. When we exclude depreciation costs, only seven airports are profitable. When depreciation is excluded, only three airports are making profits. Airports managed by local governments are very difficult to sustain financially without subsidies. Airports with more than 5.2 million passengers are profitable when depreciation is taken into account, however most local airports have fewer than 2.5 million passengers. When depreciation costs are excluded, airports need at least 2.7 million passengers to be viable.  相似文献   
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