Egg Thiamine Status of Lake Ontario Salmonines 1995–2004 with Emphasis on Lake Trout

Alewives (Alosa pseudoharengus), the major prey fish for Lake Ontario, contain thiaminase. They are associated with development of a thiamine deficiency in salmonines which greatly increases the potential for developing an early mortality syndrome (EMS). To assess the possible effects of thiamine deficiency on salmonine reproduction we measured egg thiamine concentrations for five species of Lake Ontario salmonines. From this we estimated the proportion of families susceptible to EMS based on whether they were below the ED20, the egg thiamine concentration associated with 20% mortality due to EMS. The ED20s were 1.52, 2.63, and 2.99 nmol/g egg for Chinook salmon (Oncorhynchus tshawytscha), lake trout (Salvelinus namaycush), and coho salmon (Oncorhynchus kisutch), respectively. Based on the proportion of fish having egg thiamine concentrations falling below the ED20, the risk of developing EMS in Lake Ontario was highest for lake trout, followed by coho (O. kisutch), and Chinook salmon, with the least risk for rainbow trout (O. mykiss). For lake trout from western Lake Ontario, mean egg thiamine concentration showed significant annual variability during 1994 to 2003, when the proportion of lake trout at risk of developing EMS based on ED20 ranged between 77 and 100%. Variation in the annual mean egg thiamine concentration for western Lake Ontario lake trout was positively related (p < 0.001, r² = 0.94) with indices of annual adult alewife biomass. While suggesting the possible involvement of density-dependent changes in alewives, the changes are small relative to egg thiamine concentrations when alewife are not part of the diet and are of insufficient magnitude to allow for natural reproduction by lake trout.     

Using Similarity Analyses to Scale Out Research Findings Across Andean Watershed Basins

Abstract

Strategic research in agriculture and natural resources carried out by international research centers is deemed a public good and should, sooner or later, be put into the hands of development, governmental and non-governmental organizations. However, this research is usually done at specific pilot sites; there is a greater need to know how representative those sites are in relation to the diversity of contexts in other locations. Such is the case with the Challenge Program on Water and Food (CPWF), a global initiative in water research promoted by the Consultative Group on International Agricultural Research (CGIAR), which is developing and implementing strategic research in nine basins located in the tropics of Africa, Asia and South America. Given that resources are not available to collect data from the whole of the region, pilot sites are needed. It is hoped that research outputs obtained in the selected pilot sites can be the basis for scaling out solutions to similar situations in neighbouring or adjacent areas in same or different basins.

In order to contribute to the scaling-out process, different classification methodologies were applied to determine how specific watershed basins are representative of larger areas. The Andean eco-region served as a case study but the methods can easily be applied in other regions. The spatial diversity of biophysical and social conditions across the Andes requires careful site selection. Two methods, a combination of Weight of Evidence (WofE) and Logistic Regression (LR) methods and Fast Cluster analysis, were used to determine the similarity of selected sites with those excluded. A 1-km study resolution covering most of the Andes eco-region included annual rainfall, elevation, length of growing period, land cover, roads and population density as the key variables. Results showed complementarities between the two methods in presenting a probability surface of similarity across the Andes and a clustering of similar sites inside and outside the pilot basins. The output information forms a strong basis for devising plans to scale out research findings from the pilot basins to the whole region.     

AIDS and African Development

Because AIDS affects primarily the most productive age groupand is fatal and widespread, it will have a larger impact onAfrican development than other more common diseases. Infectionrates are higher in urban than in rural areas, and studies suggestthat they are highest among urban high-income, skilled men andtheir partners. Macroeconomic models show that the greater theinfection rate among educated workers and the greater the propensityto finance medical care out of savings, the more detrimentalis the impact of AIDS on the growth of per capita income. Regardlessof the macroeconomic effect, most households and businessesdirectly affected by AIDS will be economically worse off, atleast in the short run. It is not clear, however, what effectAIDS will have on poverty in Sub-Saharan Africa or on incomeinequality. Governments need to assess the potential economicimpact of AIDS, implement cost-effective programs to mitigatethe impact, and target prevention programs to the economic sectorsmost sensitive to HIV infection.      

The future of health futures : Another perspective

A good ‘market’ for health futures and easy access to relevant information are among the reasons that health futures is currently centred in the wealthy nations. Interest in health futures is growing in the less developed countries, however, in part because of efforts by WHO and its regional office. Many benefits can be expected if the field becomes more international, including an influx of fresh ideas about health futures study designs and about innovative approaches to health care. A shift to a more global orientation is also imperative simply because health futures deals with the well-being of human beings, and most human beings live in the less developed countries of the world.     

Pedestrian traffic injuries in Mexico: A country update

Road traffic injuries in general and pedestrian injuries in particular are a major public health problem in Mexico, especially in large urban areas. Analysis of mortality and road crashes at the national level was done using routine data recorded on death certificates. Fatality rates for different age groups were estimated by region for the year 2000. These data were supplemented by a cross-sectional study of pedestrian injuries in Mexico City based on death certificates information for pedestrians who lived and died in Mexico City between 1994 and 1997. Participant observation of physical spaces where crashes occurred was carried out. The spaces were filmed and in-depth interviews of survivors conducted. Road traffic crashes were responsible for approximately 17,500 deaths in Mexico during 2000. The mean age of the victims was 37 years. Mexico lost an average of 30 years of productive life for each individual who died in a traffic crash – 525,000 years in 2000. An estimated 9500 (54.3%) of all fatalities were pedestrians, and for every pedestrian death there were 13 others who sustained nonfatal injuries requiring medical care. The overall crude mortality rate for pedestrian injuries in Mexico City was 7.14 per 100,000 (CI 6.85-7.42). A concentration of deaths was observed in 10 neighborhoods at specific types of street environments. The underlying factors included dangerous crossings and the absence or inadequacy of pedestrian bridges, as well as negative perceptions of road safety by pedestrians. In conclusion, this study demonstrates the importance of elucidating the underlying contextual determinants of pedestrian injuries.     

Ingredients in the Early Development of the U.S. Biotechnology Industry

This paper explores the ingredients that stimulated the development of the biotechnology industry in the US and contrasts conditions with those in Europe. It examines relationships between established firms and new start-ups; the financing and managerial environment and the organizational environment, whereby firms were able to set up networks of alliances. Its main findings are that: 1) The funding of the medical science research base has been substantially more generous in the U.S. than Europe. It is the funding of the science base rather than of the biotechnology industry directly that has provided the foundations for start-ups to be created out of the science base. 2) It has been easier for U.S. academics to found start-ups, close to their research establishment, and to retain their academic posts and status as well as be involved in a commercial enterprise. In Europe, the scientific/academic and commercial worlds have a wider divide. 3) Start-ups have been concentrated in the therapeutics and agricultural fields, with strong scientific research inputs into their commercialization, in contrast to other sectors where downstream processing innovations have been more important, which have been undertaken in-house by the large incumbent companies. 4) Financing and managerial conditions have been significantly easier in the U.S. for start-ups, in terms of access to venture capital specialising in high technology, ability to use the stock market to raise capital, and access to people able to forge links between scientists and entrepreneurs, and to introduce managerial expertise into new companies. 5) There has been a greater facility in the U.S. than in Europe for alliances to be formed between incumbent companies and indigenous U.S. start-ups; European start-ups have not found similar backing from European incumbent companies.     

The Altrurian Economics of William Dean Howells

A bstract . In two of his novels , A TRAVELER FROM ALTRURIA and THROUGH THE EYE OF THE NEEDLE, William Dean Howells describes the ideal commonwealth of Australia where the production and distribution of goods and services do not occur in self-regulating markets such as those found in Western-world economies. Thus, traditional economic theories are limited in analyses of the Australian economy, and critics are hampered in their efforts to understand Howelis'Utopia. This study synthesizes Howells'criticisms of the harshness of 19th-century American capitalism as presented in the two novels and then analyzes the economic structure of Australia by using Karl Polanyi's framework for studying non-market societies. This framework includes the concepts of reciprocity, redistribution , and administered trade.     

Determinants of the Physical Demand for Gold: Evidence from Panel Data

Although the role of gold in the world economy has declined since the gold standard was abandoned, it remains important as a central bank reserve, a hedge against risks, a barometer of geopolitical uncertainty, and an input for jewellery. While portfolio demand for gold has been well studied, determinants of physical demand are less understood. Certain emerging‐market countries such as China and India import substantial amounts of gold, with several factors that may contribute: low financial development, need for precautionary savings and/or strong cultural valuation of gold itself. This article uses panel data on gold imports of 21 countries to examine determinants of physical demand. We find that determinants of physical demand differ from those of portfolio demand, and that they differ between the developed and developing worlds.     

National 21st century studies : Model for an effective approach

National 21st century studies are being carried out in most parts of the world today and are gaining considerable attention. These studies share certain key characteristics that set them apart from many future studies, yet they also exhibit quite a variety of differences, including ones in sectoral coverage, methodology, and purpose. The significance of these variations is discussed in this article, which also outlines, on the basis of the studies to date, a model for an effective national 21st century study.