1,219 research outputs found

    Activist Agriculture: Farm protest in Iowa, 1929-1969

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    Throughout the twentieth century, farmers in Iowa and the Midwest struggled to make a living off their land and hard work. Post-war price busts and the Great Depression only exacerbated the general erosion in farm parity as increasing costs of production were not matched by an increase in farm commodity prices. In response, farmers organized in an effort to move from being victims of the economic and social situation to self-determined shapers of action. In this exhibit, we take a closer look at mobilization of farmers to confront and obstruct tuberculosis testing of cattle during the Iowa Cow Wars of the early 1930s and the commodity holding actions of the National Farmers Organization (NFO) in the 1960s. The exhibit will cover the actions and methods used by the farmers as well as how they leveraged the media to affect change. Finally, we look at the parallel struggles of migrant farm workers to improve wages and working conditions, examining the efforts both to pass legislation in Iowa in support of migrant farm workers and to support the Delano Grape Strike in California and the related international boycott.https://lib.dr.iastate.edu/speccoll_exhibits/1003/thumbnail.jp

    The Role of Sister Citiesā€™ Staff Exchanges in Developing ā€œLearning Citiesā€: Exploring Necessary and Sufficient Conditions in Social Capital Development Utilizing Proportional Odds Modeling

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    In the last half century former international adversaries have become cooperators through networking and knowledge sharing for decision making aimed at improving quality of life and sustainability; nowhere has this been more striking then at the urban level where such activity is seen as a key component in building ā€œlearning citiesā€ through the development of social capital. Although mega-cities have been leaders in such efforts, mid-sized cities with lesser resource endowments have striven to follow by focusing on more frugal sister city type exchanges. The underlying thesis of our research is that great value can be derived from city-to-city exchanges through social capital development. However, such a study must differentiate between necessary and sufficient conditions. Past studies assumed necessary conditions were met and immediately jumped to demonstrating the existence of structural relationships by measuring networking while further assuming that the existence of such demonstrated a parallel development of cognitive social capital. Our research addresses this lacuna by stepping back and critically examining these assumptions. To accomplish this goal we use a Proportional Odds Modeling with a Cumulative Logit Link approach to demonstrate the existence of a common latent structure, hence asserting that necessary conditions are met

    Rapid Effective Trace-Back Capability Value in Reducing the Cost of a Foot and Mouth Disease Event

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    This study evaluates how the availability of animal tracing affects the cost of a hypothetical Foot and Mouth Disease (FMD) outbreak in the Texas High Plains using alternative tracing scenarios. To accomplish this objective, the AusSpread epidemic disease spread model (Ward et al., 2006) is used to simulate a High Plains FMD outbreak under different animal tracing possibilities. A simple economic costing module (Elbakidze, 2008) is used to determine the savings in terms of animal disease mitigation costs from rapid, effective trace-back. The savings from increased traceability are then be compared to the cost of a functional National Animal Identification System (NAIS). Initial results indicate that rapid, effective tracing reduces the overall cost of disease outbreaks and that the benefits per animal in terms of reduced cost of an outbreak more than outweigh the annualized cost per animal of implementing a NAIS. A value of time related to controlling an outbreak is estimated to have increased benefits from an identification system that incorporates a rapid response capability. We also find the level of benefits vary depending on the location of initial infection and whether or not welfare slaughter occurs.Traceability, Foot and Mouth Disease, Economics, Agricultural and Food Policy, Livestock Production/Industries,

    Maximum Likelihood Estimation of Individual Inbreeding Coefficients and Null Allele Frequencies

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    In this paper, we developed and compared several expectation-maximization (EM) algorithms to find maximum likelihood estimates of individual inbreeding coefficients using molecular marker information. The first method estimates the inbreeding coefficient for a single individual and assumes that allele frequencies are known without error. The second method jointly estimates inbreeding coefficients and allele frequencies for a set of individuals that have been genotyped at several loci. The third method generalizes the second method to include the case in which null alleles may be present. In particular, it is able to jointly estimate individual inbreeding coefficients and allele frequencies, including the frequencies of null alleles, and accounts for missing data. We compared our methods with several other estimation procedures using simulated data and found that our methods perform well. The maximum likelihood estimators consistently gave among the lowest root-mean-square-error (RMSE) of all the estimators that were compared. Our estimator that accounts for null alleles performed particularly well and was able to tease apart the effects of null alleles, randomly missing genotypes and differing degrees of inbreeding among members of the datasets we analysed. To illustrate the performance of our estimators, we analysed previously published datasets on mice (Mus musculus) and white-tailed deer (Odocoileus virginianus)

    Computational Study Of Molecular Hydrogen In Zeolite Na-A. I. Potential Energy Surfaces And Thermodynamic Separation Factors For Ortho And Para Hydrogen

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    We simulate H-2 adsorbed within zeolite Na-A. We use a block Lanczos procedure to generate the first several (9) rotational eigenstates of the molecule, which is modeled as a rigid, quantum rotor with an anisotropic polarizability and quadrupole moment. The rotor interacts with Na cations and O anions; interaction parameters are chosen semiempirically and the truncation of electrostatic fields is handled with a switching function. A Monte Carlo proceedure is used to sample a set of states based on the canonical distribution. Potential energy surfaces, favorable adsorbtion sites, and distributions of barriers to rotation are analyzed. Separation factors for ortho-parahydrogen are calculated; at low temperatures, these are controlled by the ease of rotational tunneling through barriers. (C) 1999 American Institute of Physics

    Quantitative proteomic analysis by iTRAQĀ® for the identification of candidate biomarkers in ovarian cancer serum

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    <p>Abstract</p> <p>Background</p> <p>Ovarian cancer is the most lethal gynecologic malignancy, with the majority of cases diagnosed at an advanced stage when treatments are less successful. Novel serum protein markers are needed to detect ovarian cancer in its earliest stage; when detected early, survival rates are over 90%. The identification of new serum biomarkers is hindered by the presence of a small number of highly abundant proteins that comprise approximately 95% of serum total protein. In this study, we used pooled serum depleted of the most highly abundant proteins to reduce the dynamic range of proteins, and thereby enhance the identification of serum biomarkers using the quantitative proteomic method iTRAQ<sup>Ā®</sup>.</p> <p>Results</p> <p>Medium and low abundance proteins from 6 serum pools of 10 patients each from women with serous ovarian carcinoma, and 6 non-cancer control pools were labeled with isobaric tags using iTRAQ<sup>Ā® </sup>to determine the relative abundance of serum proteins identified by MS. A total of 220 unique proteins were identified and fourteen proteins were elevated in ovarian cancer compared to control serum pools, including several novel candidate ovarian cancer biomarkers: extracellular matrix protein-1, leucine-rich alpha-2 glycoprotein-1, lipopolysaccharide binding protein-1, and proteoglycan-4. Western immunoblotting validated the relative increases in serum protein levels for several of the proteins identified.</p> <p>Conclusions</p> <p>This study provides the first analysis of immunodepleted serum in combination with iTRAQ<sup>Ā® </sup>to measure relative protein expression in ovarian cancer patients for the pursuit of serum biomarkers. Several candidate biomarkers were identified which warrant further development.</p

    Fatty acids elucidate sub-Antarctic stream benthic food web dynamics invaded by the North American beaver (Castor canadensis)

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    Despite being remote, polar and sub-polar regions are increasingly threatened by global ecological change. For instance, South Americaā€™s sub-Antarctic forest ecoregion is considered one of the worldā€™s last wilderness areas and a global reference site for pre-Industrial Revolution nutrient cycles. Nonetheless, the North American beaver (Castor canadensis) was introduced to Tierra del Fuego in 1946 and, as an invasive ecosystem engineer, has transformed the ecology of regional watersheds. Beaversā€™ engineering activities transform forested streams (FS) into beaver ponds (BP), where there is greater light and primary production (allochthonous organic matter) and, consequently, increased basal resource quality. To investigate this, we analyzed algal, diatom, fungal and bacterial fatty acid (FA) biomarkers in three basal resource categories (biofilm, very fine benthic organic matter, coarse benthic organic matter) and benthic consumers from four functional feeding groups (FFG). The amphipod Hyalella spp. was chosen as an indicator species due to its abundance and biomass in both habitats. Hyalella spp. had higher proportions of algal and bacterial FA in BP than FS. In FS, Hyalella spp. (gatherer) and Gigantodax spp. (filterer, Diptera) had greater contributions of higher quality FA (higher in polyunsaturated FA), while Rheochorema magallanicum (predator, Trichoptera) and Meridialaris spp. (scraper, Ephemeroptera) showed lower quality monounsaturated and saturated FA. All FFGs showed evidence of microbial FA and had higher levels of autochthonous FA biomarkers than their food resources. Scrapers had the greatest proportion of autochthonous FA. These data provide new insights into the utilization of basal resources by stream consumers in sub-Antarctic streams and how beavers modify these ecosystems.Fil: Anderson, Christopher Brian. Consejo Nacional de Investigaciones CientĆ­ficas y TĆ©cnicas. Centro Austral de Investigaciones CientĆ­ficas; Argentina. Universidad Nacional de Tierra del Fuego, AntĆ”rtida e Islas del AtlĆ”ntico Sur. Instituto de Ciencias Polares, Ambientales y Recursos Naturales; ArgentinaFil: Tagliaferro, Marina Beatriz. Consejo Nacional de Investigaciones CientĆ­ficas y TĆ©cnicas. Centro Austral de Investigaciones CientĆ­ficas; ArgentinaFil: Fisk, Aaron. University of Guelph; CanadĆ”Fil: Rosemond, Amy D.. University of Georgia; Estados UnidosFil: Sanchez, Marisol. University of North Texas; Estados UnidosFil: Arts, Michael T.. Ryerson University; Canad

    Modeling Cross-Border Regions, Place-Making, and Resource Management: A Delphi Analysis

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    Along international borders, spillover of resource management issues is a growing challenge. Development of cross-border regions (CBRs) is seen as an emerging means of addressing these issues. A set of theoretical models, geo-economic mobilization and a resource-focused territorial program of place-making have been proposed as a lens for understanding why such change could occur. From this theory, we identify three Cā€™s as critical initial or necessary conditions to start the process: common territorial identity, convergence of knowledge and values, willingness for cooperation. We then utilize results of a Delphi study in the Fraser Lowland, a sub-district of the American-Canadian Cascadia borderland, to test if these three are present and actively working together. Our analysis based on both cumulative logit and mixed-effect modeling confirms the active existence of the three Cā€™s demonstrating the value of these theoretical models. However, the Delphi also shows that not all in this region are convinced of cross-border convergence and case studies provide mixed signals of successful cross-border resource management, indicating that sufficient conditions are yet to be fully met. Thus, our results confirm the value of these models as a lens to view events, but leave many questions to be researched
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