53 research outputs found

    Forecasts of Wastepaper Supply and Consumption In The United States To 1985

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    Recycling of wastepaper is a partial solution to the solid waste management problem and a source of fibrous material in the production of paper and board products. Unlike virgin fiber, wastepaper is the result of past paper and board consumption. To consider these important facts and others affecting wastepaper supply and consumption, a model of the paper and board industry inclusive of wastepaper recycling was constructed. The results of application of this model showed that wastepaper supply and consumption can vary widely depending on the future recovery rates and utilization levels of wastepaper by the paper industry. By assuming the most optimistic wastepaper recovery and utilization increases by 1985, a domestic wastepaper supply shortfall is forecasted. However, the most likely future wastepaper utilization scenario indicates a surplus of wastepaper by 1985 given average recovery rates. The model can be used to consider a broad range of wastepaper recovery and utilization situations and alternative economic growth rates

    Evaluation of interactions within a shelterbelt agroecosystem

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    A tree shelterbeit comprised of four rows of hybrid poplars was established near Ogden, Iowa in 1992 to evaluate shelterbeit characteristics and impacts on soil water content and crop growth andyieid. Major emphasis was on testing crops of corn and soybeans. The first three years saw little effects from the shelterbeit, and data from these years will be used to develop a baseline for future measurements. In the fourth and fifth years, corn yield patterns suggested that the shelterbeit increases yields in the zone leeward from the shelterbeit. Soybeans have not shown a response to the presence of the shelterbeit

    Demonstration of an agroforestry system to minimize pollution hazards from land application of treated municipal sludge

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    Iowa has over 700 communities that generate municipal biosolids by various treatment means. These biosolids contain valuable nutrients. In this study, municipal biosolids are applied to trees, perennial grasses, and corn/soybean crops in an alley cropping (repeated tree strips combined with crops) system. The goal is to produce economical quantities of biomass and grains with reduced use of fossil fuel-based fertilizers and minimal environmental impacts

    Improving tree establishment with forage crops

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    Weed competition and economics are two common barriers to Iowa farmers\u27 investing in tree plantings. This project examined seven weed control strategies and investigated productivity of small grain/forage combinations raised with trees in an effort to suggest management options that would encourage tree planting in the state

    Tumor Necrosis Factor–Alpha Gene Expression in Human Whole Blood

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    Tumor necrosis factor‐alpha (TNF) is recognized as a principal mediator of a variety of pathophysiologic and immunologic events. Lipopolysaccharide (LPS) challenge, either in vitro or in vivo, results in significant TNF production. In this study we present data demonstrating LPS‐induced TNF mRNA expression and bioactivity using an in vitro tissue system of whole blood (WB). The kinetics of LPS‐induced TNF production by WB was significantly accelerated as compared to isolated cultured peripheral blood monocytes (PBM). At post‐LPS challenge, plasma from WB demonstrated a rapid rise in TNF bioactivity, peaking by 4 hr (1,021 units/ml/106 cells), plateauing between 4 and 8 hr, and then decreasing over the next 16 hr. In contrast, the highest measured TNF bioactivity from PBM did not occur until the 24‐hr time‐point (175 units/ml/106 cells). Whole blood buffy‐coat TNF mRNA was assessed by Northern blot analysis, and demonstrated significant TNF mRNA accumulation at 1 hr and a peak 2 hr post‐LPS challenge. By 8 hr TNF mRNA was undetectable. Concomitant administration of LPS with either prostaglandin E2 (10‐6M) or Dexamethasone (10‐6M) resulted in significant suppression of LPS‐induced TNF production. This data supports WB as a useful in vitro medium for the molecular and cellular analyis of TNF. As specialized connective tissue, WB may provide an important environment to study the pharmacologic manipulation of TNF mRNA and bioactivity.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141678/1/jlb0366.pd
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