572 research outputs found

    Dimensions of Farm Commodity Production: Horses, Strawberries, and Why

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    To better understand the social context of food and fiber production, more and more researchers are beginning to study the production of agricultural commodities as independent, dependent, and intervening variables. Typically, these commodity variables are measured in terms of separate crop or livestock products or by ad hoc indexes that summarize several commodities. To assess and better understand the spectrum of farm commodities examined in such research, this study uses North Carolina data from the U.S. Census of Agriculture to factor analyze various indicators of crop and livestock production and to determine any underlying, empirical dimensions. Explanations of the empirical combinations involve ecological relationships, biotechnical and geographic patterns, and agricultural coincidence. These dimensions offer a basis for improved measurement and indexing of commodity production as well as a basis for analyzing related variables such as siting agribusinesses and services, or studying impacts on social well-being in farm areas

    A major subtropical fruit pest accumulates in crop fields and spills over to a wild host

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    This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Wild plant species are often considered a source of crop pests in mixed landscapes but this view rarely considers pest spillover in the opposite direction (from crop fields to natural vegetation), or spatiotemporal variability in resources between crop and wild habitats. We investigate how infestation of mango crop (Mangifera indica, Anacardiaceae) and a related wild host (marula, Sclerocarya birrea, Anacardiaceae) by a major subtropical fruit crop pest (Ceratitis cosyra, Diptera: Tephritidae) varies with distance from the boundary between crop and natural vegetation. We determined how infestation of marula is associated with proximity to mango crops at field and landscape scales over two fruiting seasons on three farms in north-eastern South Africa. This is one of few studies to date to consider pest spillover from crop fields to natural vegetation and the only one performed in a biodiverse region with relatively little habitat transformation. Over three sampling periods, C. cosyra infestation of marula always decreased with distance from mango fields. At the landscape scale, marula alongside crop fields were 30 times more likely to be infested than in distant vegetation (1.3–6 km from mango), suggesting that spillover occurs from crop fields to natural vegetation. During late mango and marula fruiting, twice as many flies infested marula than mango. However, over the two months post-mango fruiting, up to 25 times more C. cosyra were trapped in mango fields than in bordering natural vegetation. Although pests spillover from crop fields into natural vegetation to use marula as an alternate host, biological control in the natural vegetation may eliminate this habitat as a pest reservoir outside the crop season. Other nearby crops may be more important than wild hosts for maintaining C. cosyra out of mango season. Landscape planning should consider proximity and arrangement of fields containing crops that host shared pests at different times of the year.This research was supported by the Mare Curie International Research Staff Exchange Scheme [Contract number 318929]; the National Research Foundation of South Africa [Grant number 90139]; and the South African Department of Science and Technology [Contract number 0054/2013]

    DJ-1 is not a deglycase and makes a modest contribution to cellular defense against methylglyoxal damage in neurons

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    Human DJ-1 is a cytoprotective protein whose absence causes Parkinson\u27s disease and is also associated with other diseases. DJ-1 has an established role as a redox-regulated protein that defends against oxidative stress and mitochondrial dysfunction. Multiple studies have suggested that DJ-1 is also a protein/nucleic acid deglycase that plays a key role in the repair of glycation damage caused by methylglyoxal (MG), a reactive α-keto aldehyde formed by central metabolism. Contradictory reports suggest that DJ-1 is a glyoxalase but not a deglycase and does not play a major role in glycation defense. Resolving this issue is important for understanding how DJ-1 protects cells against insults that can cause disease. We find that DJ-1 reduces levels of reversible adducts of MG with guanine and cysteine in vitro. The steady-state kinetics of DJ-1 acting on reversible hemithioacetal substrates are fitted adequately with a computational kinetic model that requires only a DJ-1 glyoxalase activity, supporting the conclusion that deglycation is an apparent rather than a true activity of DJ-1. Sensitive and quantitative isotope-dilution mass spectrometry shows that DJ-1 modestly reduces the levels of some irreversible guanine and lysine glycation products in primary and cultured neuronal cell lines and whole mouse brain, consistent with a small but measurable effect on total neuronal glycation burden. However, DJ-1 does not improve cultured cell viability in exogenous MG. In total, our results suggest that DJ-1 is not a deglycase and has only a minor role in protecting neurons against methylglyoxal toxicity

    Implications of climate change for managing urban green infrastructure in Indiana

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    Urban areas around the world are increasingly investing in networks of urban forests, gardens, and other forms of green infrastructure for its many benefits, including enhanced livability, sustainability, and climate change mitigation and adaptation. Proactive planning for climate change requires anticipating potential climate change impacts to green infrastructure and adjusting management strategies accordingly. We apply climate change projections for Indiana to assess the possible impacts of climate change on common forms of urban green infrastructure, and identify management implications. Projected changes in Indiana’s temperature and precipitation could pose numerous management challenges for managing urban green infrastructure, including water stress; pests, weeds, disease and invasive species; flooding; frost risk; and timing of maintenance. Meeting these challenges will involve managing for key characteristics of resilient systems (e.g. biodiversity, redundancy) as well as more specific strategies addressing particular climate changes (e.g. shifting species compositions, building soil water holding capacity). Climate change also presents opportunities to promote urban green infrastructure. Unlike human built infrastructure, green infrastructure is conducive to grassroots stewardship and governance, relieving climate change-related strains on municipal budgets. Many online resources for adapting urban green infrastructure to climate change are already available, and emerging research will enhance understanding of best management practices

    Evaluation of the Value of Fiber in Distillers Grains Plus Solubles on Performance of Finishing Cattle

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    A finishing study was conducted to determine the value of the fiber in distillers grains plus solubles on cattle performance. Five treatments were evaluated: a corn control diet, 20 or 40% modified distillers grains plus solubles, plus two diets containing corn germ meal and corn bran balanced to equal the fiber content of the two modified distillers grains plus solubles diets. Th ere was a significant improvement in ADG and F:G for cattle fed modified distillers grains plus solubles compared to control. Cattle fed the corn germ meal and bran diets had increased DMI, slightly lower ADG, and poorer F:G compared to the control. Th e isolated fiber component had 83– 90% the feeding value of corn, while modified distillers grains plus solubles had 107– 108%. Other components in distillers besides fiber must improve the value of distillers compared to corn

    Endometrial Carcinoma: A Review of Chemotherapy, Drug Resistance, and the Search for New Agents

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    The article examines current treatment options in patients with endometrial carcinoma, the role of drug resistance, and the rationale for the use of epothilones in treating this disease

    Seasonal fluxes of carbon monoxide from an intensively grazed grassland in Scotland

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    Fluxes of carbon monoxide (CO) were measured using a fast-response quantum cascade laser absorption spectrometer and the eddy covariance method at a long-term intensively grazed grassland in southern Scotland. Measurements lasted 20 months from April 2016 to November 2017, during which normal agricultural activities continued. Observed fluxes followed a regular diurnal cycle, peaking at midday and returning to values near zero during the night, with occasional uptake observed. CO fluxes correlated well with the meteorological variables of solar radiation, soil temperature and soil moisture content. Using a general additive model (GAM) we were able to gap fill CO fluxes and estimate annual fluxes of 0.38 ± 0.046 and 0.35 ± 0.045 g C m−2 y−1g C m−2 y−1 for 2016 and 2017, respectively. If the CO fluxes reported in this study are representative of UK grasslands, then national annual emissions could be expected to be in the order of 61.91 (54.3–69.5) Gg, which equates to 3.8% (3.4–4.3%) of the current national inventory total
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