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John A Fox - One of the best experts on this subject based on the ideXlab platform.
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demand for beef from cattle administered Growth Hormones or fed genetically modified corn a comparison of consumers in france germany the united kingdom and the united states
American Journal of Agricultural Economics, 2003Co-Authors: Jayson L Lusk, Jutta Roosen, John A FoxAbstract:We compare consumer valuations of beef ribeye steaks from cattle produced without Growth Hormones or genetically modified corn in France, Germany, the United Kingdom, and the United States. Results suggest that French consumers place a higher value on beef from cattle that have not been administered added Growth Hormones than U.S. consumers; however, valuations of non-hormone-treated beef are statistically indistinguishable across Germany, the United Kingdom, and the United States. Results also suggest that European consumers place a much higher value on beef from cattle that have not been fed genetically modified corn than U.S. consumers. Copyright 2003, Oxford University Press.
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consumer demand for mandatory labeling of beef from cattle administered Growth Hormones or fed genetically modified corn
Journal of Agricultural and Applied Economics, 2002Co-Authors: Jayson L Lusk, John A FoxAbstract:This study estimates the value of policies that would mandate labeling of beef from cattle produced with Growth Hormones or fed genetically modified corn. At no cost, 85 percent of respondents desired mandatory labeling of beef produced with Growth Hormones and 64 percent of respondents preferred mandatory labeling of beef fed genetically modified corn. Estimates suggest that consumers would be willing to pay 17.0 percent and 10.6 percent higher prices for beef on average to obtain information provided via mandatory labeling about whether the beef is from cattle produced with Growth Hormones or fed genetically modified corn, respectively.
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demand for beef from cattle administered Growth Hormones or fed genetically modified corn a comparison of consumers in france germany the united kingdom and the united states
2001 Annual meeting August 5-8 Chicago IL, 2001Co-Authors: Jayson L Lusk, Jutta Roosen, John A FoxAbstract:This study compares consumer valuations of beef steaks from cattle produced without Growth Hormones or genetically modified corn in France, Germany, the United Kingdom, and the United States. In general, European consumers place a higher value on beef from cattle that have not been administered Growth Hormones and/or fed genetically modified corn than United States consumers. There is a larger divergence between the two cultures with regard to the issue of biotechnology and genetic engineering than with the issue of Growth Hormones. Results suggest that liberalizing trade policy for hormone-treated beef may be welfare reducing for the European Union.
Andrew P. Bassom - One of the best experts on this subject based on the ideXlab platform.
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models for gibberellic acid transport and enzyme production and transport in the aleurone layer of barley
Journal of Theoretical Biology, 2010Co-Authors: Ricky Obrien, Nev Fowkes, Andrew P. BassomAbstract:Gibberellins are Growth Hormones produced in the embryo of grain released during germination. They promote Growth through the production of enzymes in the aleurone layer surrounding the endosperm. These enzymes then diffuse into the endosperm and produce the sugars required by the growing acrospire. Here we model the transport of gibberellins into and along the aleurone layer, the consequent production of enzymes, and their transport into the endosperm. Simple approximate solutions of the governing equations are obtained which suggest that the enzymes are released immediately behind a gibberellin front which travels with almost constant speed along the aleurone layer. The model also suggests that this propagation speed is determined primarily by conditions near the scutellum–aleurone junction, which may enable the embryo to actively control the germination process.
Susan E Hankinson - One of the best experts on this subject based on the ideXlab platform.
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the combined influence of multiple sex and Growth Hormones on risk of postmenopausal breast cancer a nested case control study
Breast Cancer Research, 2011Co-Authors: Shelley S Tworoger, Bernard Rosner, Walter C Willett, Susan E HankinsonAbstract:Introduction: Sex and Growth Hormones are positively associated with postmenopausal breast cancer risk. However, few studies have evaluated the influence of multiple Hormones simultaneously. Methods: We considered the roles of estrone, estradiol, estrone sulfate, testosterone, androstenedione, dehydroepiandrosterone (DHEA), DHEA sulfate and prolactin and, secondarily, insulin-like Growth factor 1 (IGF-1) and c-peptide in postmenopausal breast cancer risk among 265 cases and 541 controls in the prospective Nurses’ Health Study. We created several hormone scores, including ranking women by the number of Hormones above the age- and batch-adjusted geometric mean and weighting hormone values by their individual associations with breast cancer risk. Results: Women in the top versus bottom quintile of individual estrogen or androgen levels had approximately a doubling of postmenopausal breast cancer risk. Having seven or eight compared to zero Hormones above the geometric mean level was associated with total (RR = 2.7, 95% CI = 1.3 to 5.7, P trend < 0.001) and estrogen receptor (ER)-positive (RR = 3.4, 95% CI = 1.3 to 9.4, P trend < 0.001) breast cancer risk. When comparing the top versus bottom quintiles of the score weighted by individual hormone associations, the RR for total breast cancer was 3.0 (95% CI = 1.8 to 5.0, P trend < 0.001) and the RR for ER-positive disease was 3.9 (95% CI = 2.0 to 7.5, P trend < 0.001). The risk further increased when IGF-1 and c-peptide were included in the scores. The results did not change with adjustment for body mass index.
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The combined influence of multiple sex and Growth Hormones on risk of postmenopausal breast cancer: a nested case-control study
Breast Cancer Research, 2011Co-Authors: Shelley S Tworoger, Walter C Willett, Bernard A Rosner, Susan E HankinsonAbstract:Introduction Sex and Growth Hormones are positively associated with postmenopausal breast cancer risk. However, few studies have evaluated the influence of multiple Hormones simultaneously. Methods We considered the roles of estrone, estradiol, estrone sulfate, testosterone, androstenedione, dehydroepiandrosterone (DHEA), DHEA sulfate and prolactin and, secondarily, insulin-like Growth factor 1 (IGF-1) and c-peptide in postmenopausal breast cancer risk among 265 cases and 541 controls in the prospective Nurses' Health Study. We created several hormone scores, including ranking women by the number of Hormones above the age- and batch-adjusted geometric mean and weighting hormone values by their individual associations with breast cancer risk. Results Women in the top versus bottom quintile of individual estrogen or androgen levels had approximately a doubling of postmenopausal breast cancer risk. Having seven or eight compared to zero Hormones above the geometric mean level was associated with total (RR = 2.7, 95% CI = 1.3 to 5.7, P trend < 0.001) and estrogen receptor (ER)-positive (RR = 3.4, 95% CI = 1.3 to 9.4, P trend < 0.001) breast cancer risk. When comparing the top versus bottom quintiles of the score weighted by individual hormone associations, the RR for total breast cancer was 3.0 (95% CI = 1.8 to 5.0, P trend < 0.001) and the RR for ER-positive disease was 3.9 (95% CI = 2.0 to 7.5, P trend < 0.001). The risk further increased when IGF-1 and c-peptide were included in the scores. The results did not change with adjustment for body mass index. Conclusions Overall, the results of our study suggest that multiple Hormones with high circulating levels substantially increase the risk of breast cancer, particularly ER-positive disease. Additional research should consider the potential impact of developing risk prediction scores that incorporate multiple Hormones.
Patrick Prunet - One of the best experts on this subject based on the ideXlab platform.
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Potential benefits of biotechnology in aquaculture. The case of Growth Hormones in french trout farming
Technological Forecasting and Social Change, 1993Co-Authors: Francois Bonnieux, Yoann Gloaguen, P. Rainelli, A. Faure, Benoit Fauconneau, Pierre-yves Le Bail, Gérard Maisse, Patrick PrunetAbstract:Against the background of rapidly increasing fish demand and stagnant or declining marine harvest, aquaculture or fish farming has assumed a major role in France which is set to expand. Trout farming in particular has already displayed considerable Growth and France is the leading producer in the EEC. Biotechnology holds the key to future changes in trout culture. One such technology, which trials show has potential to reduce production costs, is recombinant trout Growth hormone (rtGH). This paper sets out to perform a preliminary ex ante assessment of the possible social benefits from the adoption of rtGH by French trout producers. Several scenarios, based on possible hypotheses of supply and demand Growth, are considered. Scenarios assuming an association of the technology with diversification towards more highly processed trout products display the highest estimated welfare gains. A key factor which will determine the outcome of using rtGH is its acceptance by the public. There has already been strong adverse reaction in Europe to the use of genetically engineered Growth Hormones in meat production and to the use of bovine somatotropin to enhance milk yields. The possibility that there might be a similar response in the case of trout is examined by considering the possibility of a sharp drop in demand. Part 1 of the paper sets out the economic and technological background to biotechnological development of trout farming in France. Part 2 undertakes an ex ante assessment of potential changes in producer and consumer surplus from the adoption of rtGH applying alternative supply and demand shifts in the framework of partial equilibrium analysis.
Yuval Goldblat - One of the best experts on this subject based on the ideXlab platform.
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Plant Growth Hormones suppress the development of Harpophora maydis, the cause of late wilt in maize
Physiology and Molecular Biology of Plants, 2015Co-Authors: Ofir Degani, Ran Drori, Yuval GoldblatAbstract:Late wilt, a severe vascular disease of maize caused by the fungus Harpophora maydis, is characterized by rapid wilting of maize plants before tasseling and until shortly before maturity. The pathogen is currently controlled by resistant maize cultivars, but the disease is constantly spreading to new areas. The plant’s late phenological stage at which the disease appears suggests that plant Hormones may be involved in the pathogenesis. This work revealed that plant Growth Hormones, auxin (Indole-3-acetic acid) and cytokinin (kinetin), suppress H. maydis in culture media and in a detached root assay. Kinetin, and even more auxin, caused significant suppression of fungus spore germination. Gibberellic acid did not alter colony Growth rate but had a signal suppressive effect on the pathogens’ spore germination. In comparison, ethylene and jasmonic acid, plant senescing and defense response regulators, had minor effects on colony Growth and spore germination rate. Their associate hormone, salicylic acid, had a moderate suppressive effect on spore germination and colony Growth rate, and a strong influence when combined with auxin. Despite the anti-fungal auxin success in vitro, field experiments with dimethylamine salt of 2,4-dichlorophenoxyacetic acid (that mimics the influence of auxin) failed to suppress the late wilt. The lines of evidence presented here reveal the suppressive influence of the three Growth Hormones studied on fungal development and are important to encourage further and more in-depth examinations of this intriguing hormonal complex regulatory and its role in the maize-H. maydis interactions.
