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191.
Bill Winders Alison Heslin Gloria Ross Hannah Weksler Seanna Berry 《Agriculture and Human Values》2016,33(1):73-88
The US food regime maintained some degree of stability in terms of prices and production levels for commodities in the world economy. This food regime, resting on supply management policy, began to falter in the early 1970s. In the late-1980s and 1990s, notable changes occurred in the world economy regarding agriculture as the food regime became more market-oriented. The end of the twentieth century saw the breakdown of many institutions, organizations, and international agreements that had tried to stabilize prices and production from 1945 to 1975. This paper examines this period of change (roughly 1960–2010) and explores the effects on five commodities: cocoa, coffee, corn, soybeans, and wheat. These commodities offer important points of comparison. First, while cocoa, coffee, and wheat were regulated by international organizations and agreements, corn and soybeans were not. Second, the US dominated the international corn and soybean markets, but the cocoa, coffee, and wheat markets were much more competitive. And third, corn, soybeans, and wheat were commodities largely produced in the core of the world economy, while cocoa and coffee were produced in the periphery. Thus, comparing the effect of the fall of the US food regime on these commodities reveals the importance of previous regulation, the level of market competition, and geographic origin in the world economy. 相似文献
192.
Venkatesh B Kirkness EF Loh YH Halpern AL Lee AP Johnson J Dandona N Viswanathan LD Tay A Venter JC Strausberg RL Brenner S 《Science (New York, N.Y.)》2006,314(5807):1892
Cartilaginous fishes represent the living group of jawed vertebrates that diverged from the common ancestor of human and teleost fish lineages about 530 million years ago. We generated approximately 1.4x genome sequence coverage for a cartilaginous fish, the elephant shark (Callorhinchus milii), and compared this genome with the human genome to identify conserved noncoding elements (CNEs). The elephant shark sequence revealed twice as many CNEs as were identified by whole-genome comparisons between teleost fishes and human. The ancient vertebrate-specific CNEs in the elephant shark and human genomes are likely to play key regulatory roles in vertebrate gene expression. 相似文献
193.
Glen P. Fox Jan Bowman Alison Kelly Andy Inkerman David Poulsen Robert Henry 《Euphytica》2008,163(2):249-257
Grain samples from a combined intermediate and advanced stage barley breeding trial series, grown at two sites in two consecutive
years were assessed for detailed grain quality and ruminant feed quality. The results indicated that there were significant
genetic and environmental effects for “feed” traits as measured using grain hardness, acid detergent fibre (ADF), starch and
in-sacco dry matter digestibility (ISDMD) assays. In addition, there was strong genotypic discrimination for the regressed feed performance
traits, namely Net Energy (NE) and Average Daily Gain (ADG). There was considerable variation in genetic correlations for
all traits based on variance from the cultivars used, sites or laboratory processing effects. There was a high level of heritability
ranging from 89% to 88% for retention, 60% to 80% for protein and 56% to 68% for ADF. However, there were only low to moderate
levels of heritability for the feed traits, with starch 30–39%, ISDMD 55–63%, ADF 56–68%, particle size 47–73%, 31–48% NE
and ADG 44–51%. These results suggest that there were real differences in the feed performance of barleys and that selection
for cattle feed quality is potentially a viable option for breeding programs. 相似文献
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197.
Alison L. Duvall Alexander L. Metcalf Peter S. Coates 《Strength and Conditioning Journal》2017,70(1):129-140
The Endangered Species Act (ESA) continues to serve as one of the most powerful and contested federal legislative mandates for conservation. In the midst of heated debates, researchers, policy makers, and conservation practitioners champion the importance of cooperative conservation and social-ecological systems approaches, which forge partnerships at multiple levels and scales to address complex ecosystem challenges. However, few real-world examples exist to demonstrate how multifaceted collaborations among stakeholders who share a common goal of conserving at-risk species may be nested within a systems framework to achieve social and ecological goals. Here, we present a case study of Greater Sage-grouse (Centrocercus urophasianus) conservation efforts in the “Bi-State” region of California and Nevada, United States. Using key-informant interviews, we explored dimensions and drivers of this landscape-scale conservation effort. Three themes emerged from the interviews, including 1) ESA action was transformed into opportunity for system-wide conservation; 2) a diverse, locally based partnership anchored collaboration and engagement across multiple levels and scales; and 3) best-available science combined with local knowledge led to “certainty of effectiveness and implementation”—the criteria used by the US Fish and Wildlife Service to evaluate conservation efforts when making listing decisions. Ultimately, collaborative conservation through multistakeholder engagement at various levels and scales led to proactive planning and implementation of conservation measures and precluded the need for an ESA listing of the Bi-State population of Greater Sage-grouse. This article presents a potent example of how a systems approach integrating policy, management, and learning can be used to successfully overcome the conflict-laden and “wicked” challenges that surround at-risk species conservation. 相似文献
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199.
Ceballos H Sánchez T Denyer K Tofiño AP Rosero EA Dufour D Smith A Morante N Pérez JC Fahy B 《Journal of agricultural and food chemistry》2008,56(16):7215-7222
Only two mutations have been described in the literature, so far, regarding starch and root quality traits in cassava. This article reports on an induced mutation in this crop, first identified in 2006. Botanical seed from five different cassava families were irradiated with gamma rays. Seed was germinated, transplanted to the field (M1 plants), and self-pollinated to produce the M2 generation. Abnormal types regarding starch granule morphology were identified during the single plant evaluation of M2 genotypes. To confirm these characteristics, selected genotypes were cloned and a second evaluation, based on cloned plants obtained from vegetative multiplication, was completed in September 2007. Two M2 genotypes presented small starch granules, but only one could be fully characterized, presenting a granule size of 5.80 +/- 0.33 microm compared with three commercial clones with granule sizes ranging from 13.97 +/- 0.12 to 18.73 +/- 0.10 microm and higher-than-normal amylose content (up to 30.1% in cloned plants harvested in 2007, as compared with the typical values for "normal" cassava starch of around 19.8%). The gels produced by the starch of these plants did not show any viscosity when analyzed with the rapid viscoanalyzers (5% suspension), and the gels had low clarity. Low viscosity could be observed at higher concentrations (8 or 10% suspensions). Preliminary results suggest that the mutation may be due to a lesion in a gene encoding one of the isoforms of isoamylase (probably isa1 or isa2). 相似文献
200.
Fiorenza Micheli Andrew O. Shelton Seth M. Bushinsky Alice L. Chiu Alison J. Haupt Kimberly W. Heiman Carrie V. Kappel Margaret C. Lynch Rebecca G. Martone Robert B. Dunbar James Watanabe 《Biological conservation》2008,141(4):1078-1090
We evaluated the persistence and possible recovery of two depleted marine mollusks, the red (Haliotis rufescens) and black abalone (H. cracherodii), in central California, USA. Monitoring over 32-years did not reveal increasing or decreasing trends in red abalone abundances and sizes over the past three decades, in the absence of harvesting. Comparisons between marine reserves protected for at least 25 years and sites with open public access showed significant difference in size structure for black abalone, with individuals greater than 8 cm in shell length comprising 14–37% of animals in reserves and 2–11% at open-access sites, and a trend for greater abundances of red abalone within reserves. Despite no increasing trends, protection in one of the no-take reserves, the Hopkins marine life refuge (HMLR), has led to persistence of red abalone populations over multiple generations, at average densities of 0.2 individuals/m2. At other locations, both within the HMLR and elsewhere, red abalone densities are lower than at the location where long-term studies were conducted (av. 0.03 animals/m2), and an order of magnitude lower than for black abalone (av. 0.4 animals/m2). These results suggest that continued fishery closure and protection in no-take reserves are effective tools for allowing persistence of abalone populations, though there are no signs of recovery to levels comparable to those preceding fisheries collapse. Such failure to recover is most likely associated with high natural mortality and possibly continued illegal take, but not with processes underlying low abalone population levels elsewhere, including food or habitat limitation, recruitment failure, or disease. Linking current structure and trends to specific processes is a crucial first step towards devising focused strategies for conserving and re-building depleted marine populations. 相似文献