Economic Aspects of Agricultural and Food Biosecurity in the United States, March 2007

Concerns about biosecurity in the food system raise a variety of issues about how the system is presently organized, why it might be vulnerable, what one could reasonably do to better secure it, and the costs of doing so. After presenting some facts about US agriculture and food, this paper considers three economic aspects of the general problem. One is the global problem, or the way biosecurity measures can affect how countries relate to each other and the global consequences that result. Another is how to best manage the immediate aftermath of a realized threat in order to minimize damage. The third is how to seek to prevent realization of the threat. Some policy alternatives are also presented.

Welfare Impacts of Cross-Country Spillovers in Agricultural Research, 2007

The welfare implications of intellectual property protection (IPP) for private sector agricultural research are analyzed, focusing on the realistic cases in which countries provide different IPP levels, technology spills over across countries, and the public sector is involved in research. A model is developed to determine who benefits from, and who should pay for, the associated research. The paper contains some interesting results on the implications of a harmonization of IPP policies through multilateral agreements or via technology that allows research firms to prevent the copying of plants and animals that express traits that have emerged from their research.

Book production and the onset of modern economic growth

Endogenous growth theory suggests that human capital formation plays a significant role for the wealth and poverty of nations. In contrast to previous studies which denied the role of human capital as a crucial determinant of for really long-term growth, we confirm its importance. Indicators of human capital like literacy rates are lacking for the period of 1450-1913; hence, we use per capita book production as a proxy for advanced literacy skills. This study explains how, and to what extent, growth disparities are a function of human capital formation.

Homeostasis and in vivo effector function of antigen-specific CD4+CD25+ regulatory T cells in experimental transplantation.

CD4+CD25+ regulatory T cells (Tregs) play a critical role in the prevention of autoimmune diseases as well as in the induction and maintenance of dominant tolerance in transplantation models. While their suppressive function has been extensively studied in vitro, their homeostasis and mechanisms of immunoregulation still remain to be clarifi ed in vivo. Using a murine adoptive transfer and skin allograft model, we analysed the expansion, effector function and traffi cking of effector T cells in the presence or absence of donor-specifi c Tregs. Although hyporesponsive to allogeneic and polyclonal stimulation in vitro, transferred Tregs survived and expanded, in response to an allograft in vivo. When co-transferred with naive CD4+CD25- effector T cells, they specifi cally prevented donor but not 3rd party allograft rejection by inhibiting the production of effector cytokines rather than the proliferation of effector T cells in response to alloantigens. The co-transfer of donor-specifi c Tregs did not affect the homing of effector T cells towards the graft draining lymph nodes, but it markedly reduced the infi ltration of the allograft by these pathogenic cells. Furthermore, in recipients where donor-specifi c transplantation tolerance was induced, Tregs preferentially accumulated in the allograft draining lymph nodes and within the grafted skin itself. Taken together, our results suggest that the suppression of graft rejection is an active process that involves the persistent presence of Tregs at the site of antigenic challenge.

Chemical changes in argisols under irrigated grape production in the central São Francisco river valley, Brazil

This study compares the chemical composition of the solution and exchange complex of soil in a 3-year-old irrigated vineyard (Vitis vinifera L., Red Globe cultivar) with that of adjacent clearing in the native hyperxerophyllic 'caatinga' vegetation. The soils are classified as Plinthic Eutrophic Red-Yellow Argisol; according to Soil Taxonomy they are isohyperthermic Plinthustalfs. Detailed physiographic characterization revealed an impermeable gravel and cobble covering the crystalline rocks; the relief of this layer was more undulating than the level surface. Significant higher concentrations of extractable Na, K, Mg and Ca were observed within the vineyard. Lower soil acidity, higher Ca/Mg ratios, as well as lower sodium adsorption and Na/K ratios reflected additions of dolomitic lime, superphosphate and K-bearing fertilizers. As the water of the São Francisco River is of good quality for irrigation (C1S1), the increases in Na were primarily attributed to capillary rise from the saline groundwater table. None of the soil in the study area was found to be sodic. About 62% of the vineyard had an Ap horizon with salinity levels above 1.5dSm-1 (considered detrimental for grape production); according to average values for this horizon, a potential 13% reduction in grape production was predicted. Differences in chemical composition in function of distance to the collector canals were observed in the clearing, but not in the vineyard. The influence of differences in the elevations of the surface and impermeable layers, as well as pediment thickness, was generally weaker under irrigation. Under irrigation, soil moisture was greater in points of convergent surface waterflow; the effect of surface curvature on chemical properties, though less consistent, was also stronger in the vineyard.

Glyphosate behavior in a Rhodic Oxisol under no-till and conventional agricultural systems

The behavior of glyphosate in a Rhodic Oxisol, collected from fields under no-till and conventional management systems in Ponta Grossa, Parana state (Brazil) was investigated. Both agricultural systems had been in production for 23 years. Glyphosate mineralization, soil-bound forms, sorption and desorption kinetics, sorption/desorption batch experiments, and soil glyphosate phythoavailability (to Panicum maximum) were determined. The mineralization experiment was set up in a completely randomized design with a 2 x 2 factorial scheme (two management systems and two 14C radiolabelled positions in the glyphosate), with five replicates. 14CO2 evolution was measured in 7-day intervals during 63 days. The glyphosate sorption kinetics was investigated in a batch experiment, employing a glyphosate concentration of 0.84 mg L-1. The equilibration solution was 0.01 mol L-1 CaCl2 and the equilibration times were 0, 10, 30, 60, 120, 240, and 360 min. Sorption/desorption of glyphosate was also investigated using equilibrium batch experiments. Five different concentrations of the herbicide were used for sorption (0.42, 0.84, 1.68, 3.36, and 6.72 mg L-1) and one concentration for desorption. Glyphosate phytoavailability was analyzed in a 2 x 5 factorial scheme with two management systems and five glyphosate concentrations added to soil (0, 4.2, 8.4, 42.0, and 210.0 µg g-1) in a completely randomized design. Phytotoxicity symptoms in P. maximum were evaluated for different periods. The soil under both management systems showed high glyphosate sorption, which impeded its desorption and impaired the mineralization in the soil solution. Practically the total amount of the applied glyphosate was quickly sorbed (over 90 % sorbed within 10 min). Glyphosate bound to residues did not have adverse effects on P. maximum growth. The mineralization of glyphosate was faster under no-till and aminomethylphosphonic acid was the main glyphosate metabolite.

Production of polyesters in transgenic plants.

Polyhydroxyalkanoates (PHAs) are bacterial polyesters having the properties of biodegradable thermoplastics and elastomers. Synthesis of PHAs has been demonstrated in transgenic plants. Both polyhydroxybutyrate and the co-polymer poly(hydroxybutyrate-co-hydroxyvalerate) have been synthesized in the plastids of Arabidopsis thaliana and Brassica napus. Furthermore, a range of medium-chain-length PHAs has also been produced in plant peroxisomes. Development of agricultural crops to produce PHA on a large scale and at low cost will be a challenging task requiring a coordinated and stable expression of several genes. Novel extraction methods designed to maximize the use of harvested plants for PHA, oil, carbohydrate, and feed production will be needed. In addition to their use as plastics, PHAs can also be used to modify fiber properties in plants such as cotton. Furthermore, PHA can be exploited as a novel tool to study the carbon flux through various metabolic pathways, such as the fatty acid beta-oxidation cycle.

Production of calves following nonsurgical transfer of fresh and refrigerated bovine demi-embryos

Selostus: Vasikoiden tuottaminen tuoreilla ja kylmäsäilytetyillä halkaistuilla alkioilla

In vitro production of cattle blastocysts in chemically defined medium with or without insulin supplementation

Selostus: Insuliinin vaikutus naudan blastokystien tuottamiseen in vitro kemiallisesti tunnetussa liuoksessa

Iowa Agricultural Organization Directory, 2009

The directory of all the Agriculture organizations on Iowa. Taken from online directory on June 1, 2010.

Sustainability - a challenge to animal production and breeding

Selostus: Kestävän kehityksen vaatimukset kotieläintuotannossa ja -jalostuksessa

Effect of nitrogen fertilization, grass species and cultivar on sod production on Valkeasuo peat bog - a case study

Selostus: Typpilannoituksen, kasvilajin ja lajikkeen vaikutus siirtonurmikon tuotanto-ominaisuuksiin Valkeasuon turvetuotannon jättöalueella

Comparative effects of GLP-1-(7-36) amide, oxyntomodulin and glucagon on rabbit gastric parietal cell function.

We have investigated in vitro, the effects of glucagon-like peptide-1-(7-36) amide (GLP-1-(7-36) amide), oxyntomodulin and glucagon on two rabbit parietal cell-enriched fractions (F3, F3n), with parietal cell contents of 60% and 88%, respectively. Histamine (10(-5) M) stimulated [14C]aminopyrine accumulation to an amount of 850% in excess of the basal level, whereas GLP-1-(7-36) amide (10(-7) M) and oxyntomodulin (10(-6) M) induced increases of 50% and 30%, respectively. With a histamine concentration of 10(-6) M, [14C]aminopyrine accumulation was stimulated to 498% in excess of the basal level; GLP-1-(7-36) amide (10(-7) M) and oxyntomodulin (10(-7) M) induced increases of 18% and 15%, respectively. With these parameters, oxyntomodulin[19-37] and glucagon were without effect. Specific binding of [125I]GLP-1-(7-36) amide to parietal cell plasma membranes was inhibited dose-dependently by GLP-1-(7-36) amide, oxyntomodulin and glucagon with inhibitory concentrations of 0.25 nM, 65 nM and 800 nM, respectively. No specific binding of [125I]oxyntomodulin or [125I]glucagon was detectable. GLP-1-(7-36) amide receptor mRNA was only detected in parietal cell-enriched fractions. GLP-1-(7-36) amide, oxyntomodulin and glucagon stimulated parietal cell cAMP production to similar maximal levels with median values close to 0.28 nM, 10.5 nM and 331.7 nM, whereas oxyntomodulin[19-37] had no effect. The maximal cAMP production induced by GLP-1-(7-36) amide, oxyntomodulin or glucagon was additive to that induced by histamine.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of added glycerol or unprotected free fatty acids or a combination of the two on silage intake, milk production, rumen fermentation and diet digestibility in cows given grass silage based diets

Selostus: Väkirehuun lisätyn glyserolin tai vapaiden rasvahappojen tai näiden yhdistelmän vaikutus maidontuotantoon ja pötsifermentaatioon ruokittaessa lypsylehmiä säilörehuun perustuvalla ruokinnalla

Intralesional regulatory T-cell suppressive function during human acute and chronic cutaneous leishmaniasis due to Leishmania guyanensis.

The levels of regulatory T cells (Treg cells), analyzed by Foxp3 mRNA expression, were determined in lesions from patients with acute cutaneous leishmaniasis (ACL) and chronic cutaneous leishmaniasis (CCL). We demonstrated that Treg cells preferentially accumulate in lesions from ACL patients during the early phase of infection (lesion duration of less than 1 month). In addition, levels of Foxp3 mRNA transcripts were significantly higher in specimens from patients with CCL than in those from patients with ACL, suggesting a critical role of intralesional Treg cells in CCL. Intralesional Treg cells from both ACL and CCL patients were shown to have suppressive functions in vitro, since they inhibited the gamma interferon (IFN-gamma) produced by CD4(+) CD25(-) T cells purified from peripheral blood mononuclear cells from the same patient in response to Leishmania guyanensis stimulation. Intralesional 2,3-indoleamine dioxygenase (IDO) mRNA expression was associated with that of Foxp3, suggesting a role for IDO in the suppressive activity of intralesional Treg cells. In addition, a role, albeit minor, of interleukin-10 (IL-10) was also demonstrated, since neutralization of IL-10 produced by intralesional T cells increased IFN-gamma production by effector cells in an in vitro suppressive assay. These results confirm the role of intralesional Treg cells in the immunopathogenesis of human Leishmania infection, particularly in CCL patients.