Viruses may invade animals, plants, or bacteria, and are considered obligate parasites because they lack a complete enzyme system of their own. Reproduction occurs when the virus entity makes use of a cell's synthetic machinery to direct the synthesis of specialized particles, the virions, and transfers them to other cells. The purpose of this study was to investigate and develop methods to isolate viruses chicken embryos and bacteriophage.Viruses were concentrated from water sources following procedures outlined by Berg (1971) using standard Millipore filtering units. Virus suspensions were eluted with a beef extract solution and then inoculated into the three host systems. Growth was determined by the presence of cytopathic effects on the agar overlay or in the chicken on the chorioallantoic membrane.Cytopathic effects occurred in tissue cultures following inoculation with water samples from two sites on two consecutive sampling dates. Virus recovery in chicken embryos was 45.5% when cytopathic effects and death rates were analyses were combined. When bacteria were employed, viruses were recovered in 42.8% of samples tested.Ball State UniversityMuncie, IN 47306

The need for a green clean living environment is increasing today, with the boom of the socioeconomic development, educational level. However, the environmental pollution becomes an alerted global issue due to the large amount of wastes discharged making this need to be not easily met at the moment. Greenhouse gas emission mainly from energy, transport and agricultural land use is causing climate change because of their long atmospheric lifetime and trapping the heat in the atmosphere. Harmful effects and damages caused by environment pollution and climate change are unpredictable. It was reported that every year millions of people die because of fine particles when exposing to air pollution and other millions die from water-born diseases. Management and monitoring of air and water pollution by using GIS technology is an effective method. The measured data can be obtained continuously, quickly and accurately at stations in any regions even with complex terrain. This helps reduce the required number of employees, manage automatically and continuously a large number of data. / Ngày nay nhu cầu về một môi trường sống xanh, sạch đang gia tăng, với sự bùng nổ của phát triển kinh tế - xã hội và trình độ dân trí. Tuy nhiên, ô nhiễm môi trường đang trở thành một vấn đề cảnh báo toàn cầu do số lượng lớn các chất thải được xả ra môi trường làm cho nhu cầu này không dễ dàng được đáp ứng tại thời điểm này. Phát thải khí nhà kính chủ yếu là từ sử dụng năng lượng, giao thông vận tải và đất nông nghiệp đang gây ra biến đổi khí hậu vì thời gian tồn tại của cúng dài và giữ nhiệt trong khí quyển. Các ảnh hưởng xấu và thiệt hại gây ra bởi ô nhiễm môi trường và biến đổi khí hậu là không thể đoán trước. Thông tin báo cáo chỉ ra rằng mỗi năm có hàng triệu người chết vì hít các hạt bụi mịn khi tiếp xúc với ô nhiễm không khí; và hàng triệu người khác chết vì bệnh do nước sinh ra. Quản lý và giám sát ô nhiễm không khí và nước bằng cách sử dụng công nghệ GIS là một phương pháp hiệu quả. Các dữ liệu đo có thể được lấy liên tục, nhanh chóng và chính xác tại các trạm ở bất kể khu vực nào, ngay cả nơi có địa hình phức tạp. Điều này giúp làm giảm số lượng lao động cần thiết, quản lý tự động và liên tục một số lượng lớn dữ liệu.

China's Songhua River water pollution incident in question, by the world's attention, let the public know the problem of water pollution in China has severe course. Looking at the causes of water pollution in China may be economic development and the relationship between the two central terms. Brought about by rapid economic development of industrialization, urbanization and agricultural pollution makes water pollution from urban expansion in China to rural areas. In addition the central government and local governments in environmental protection and economic aspects had many differences that have made the central environmental protection policies are not correctly implemented at the local, for water pollution control is full of challenges. Therefore, this paper describes in detail the causes of China's water pollution problems and water resources are unevenly distributed in the central and local relations to be discussed by the conflicts, and then from the Songhua incident, China's environmental system, resulting in the evolution and development.

Abstract Industrial Economic and Environment are the main systems that construct the city we have in nowadays. The industrial economic moves the city and keeps it getting growth. The environment system lasts out the Urban Development timelessly and carries on the rubbish brought from the city activities. For a long time, the Taiwan government always aims for the high economic growth as its goal. However, the progress is much over the load and ability to the environment system. Thus it can aridly gets balance from the time of environment purification as well as the speed, quality & quantity which come from the process of economical movement. As the time goes and the situation of losing balance gets more worse. Later, it becomes the environment pollution and the water pollution of the river system is the most serious issue among those numerous ones. In nowadays, people analyses and solve the problem from the aspect of Environment Engineering as well as consider the interaction between the environment system & Urban Development, and the shortage thinking of integrated, constructive and macroscopic point of view. The main purpose to do this research is to break away the old traditional mode. Such as studying the water pollution from the viewpoint of Environment Engineering, taking System Dynamics as the foundation, having the systematical macro-aspect, idealities of construction to the river pollution in Kao-Hsiung City, plans to industrial development, policies to the government finances, setting up dynamic models to the subsystems. Also, processing the strategic simulation with the ITHINK software which is used to simulate distinct prevention of the water pollution, and probe the time concern between the service of the urban sewerage system to sewers and pollution raised speed. To make an advanced step to this research, the Urban Growth Management Strategy Analysis and BOT Public & Private Joint Model are subsumed and imported to explore the influence of long-rang variation trend to the urban water pollution. The result from the research shows that the outcomes of the sewer improvement is somewhat restricted by its lacked ability of purification, even though the improvement of sewer the service of the urban sewerage system can hold back the polluted water flow into the river surface. So, the purification speed of the river can hardly to catch up the discharge speed of polluted water. And even when the service of the urban sewerage system reaches to 100%, but the long-term accumulation has made the river hardly to reach to its standard load and ability. Thus it can be seen, the temporary solution is unable to solve the serious river pollution. The permanent cure is to integrate the Urban Growth Management Strategy. According to the simulation result, we find the water pollution in Kao-Hsiung City can be controlled and solved by combining the Urban Growth Management Strategy (Industrial reforming, levying polluted water fee), encouraging people to play a part to the sewer establishment, drain away the polluted water and renovating the river. With the result that it shows, it needs the government to study and draft prevention and rules with traditional aspect from environment engineering in the near future. More over than that, it needs the government to consider the ration between Urban Development and water pollution with integrated urban systematical viewpoint. Finally, the problem of water pollution can overall obtains the improvement effectively.

China¡¦s water pollution problem has been experienced remediation by Chinese government numerous times; however, not much improvement is seen so far. In addition, Chinese government admits that algae, nutrient and other water pollution problems will not be eliminated in short period of time. Therefore, this study examined the current situation of China¡¦s water bodies as well as the sources of the pollution, and then compared with the measures taken to the problems by the Chinese government. It is found that city and household sewage are the major factors; nevertheless, they haven been less regarded. Therefore, the government should not only maintain the past results of remediation, but also emphasize on strengthening on constructions of sewage discharge facilities and ensuring capital provided for sewage treatment plants in order to control the most water pollution sources into China¡¦s water bodies.

Doctoral thesis. / Format: PDF. Bibl.

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E. coli 0157:H7 were isolated from 0.86% (n=1520) water samples and Salmonella species from 6.04% (n=1456) samples collected within the Oldman River watershed in southern Alberta. Peak prevalence of E. coli0157:H7 in July 2000 was 6.3% (n=48). Peak prevalence of Salmonella was 16.2% (n=11) in August 1999 and 33.% (n=42) in July 2000. Prevalence was greater in water from some sampling locations than from others. In non-filtered surface water E. coli0157:H7 and S. typhimurium numbers decreased significantly faster at 20 degrees celsius than at 10 degrees celsius (P=0.000); however this difference did not exist when the same water was filtered (P=0.439). Pathogen survival in one water sample was greater when it was filtered (0.2um pore) than when it was not filtered even though there were no autochthonous bacteria in the water prior to filtration. / xi, 268 leaves ; 28 cm.

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