2,401 research outputs found

    Slavery and the Arkansas Supreme Court

    Get PDF

    Application strategy for an anthraquinonebased repellent and the protection of soybeans from Canada goose depredation

    Get PDF
    Agricultural crops can sustain extensive damage caused by Canada geese (Branta canadensis) when these crops are planted near wetlands or brood-rearing sites. From 2000 to 2015, South Dakota Game, Fish and Parks spent \u3e$5.6 million to manage damages caused by Canada geese to agricultural crops (primarily soybeans) in South Dakota, USA. For the purpose of developing a repellent application strategy for nonlethal goose damage management, we comparatively evaluated the width of anthraquinone applications (i.e., 9.4 L Flight Control® Plus goose repellent/ha [active ingredient: 50% 9,10-anthraquinone] at 0–36 m versus 0–73 m perpendicular to the edge of wetlands in 2014), the timing of the first repellent application (i.e., 9.4 L Flight Control Plus goose repellent/ha at 50% versus 75% seedling emergence in 2015), the yield of soybeans (Glycine max) within repellent-treated and untreated subplots, and anthraquinone chemical residues in Day County, South Dakota. Soybean yield was greater in subplots 73 m from the water’s edge than that in the 36-m subplots (P \u3c 0.02). Among subplots first sprayed at 50% seedling emergence, soybean yield was greater at 73 m and 82 m than that at 36 m (P \u3c 0.005). In contrast, we observed no difference in yield at 36 m, 73 m, or 82 m in the subplots first sprayed at 72% seedling emergence (P \u3e 0.09). We therefore conclude that goose damages were effectively managed in subplots first sprayed at 72% seedling emergence. Anthraquinone residues averaged 674 and 629 ppm anthraquinone upon the first application of the repellent (June to July), 22 and 35 ppm anthraquinone in the mid-season hay (August to September), and 36 and 28 ppb anthraquinone in the harvested seed (October to November) in 2014 and 2015, respectively. Our results suggest that a 73-m bandwidth of anthraquinone-based repellents first applied at approximately 72% or 65–85% seedling emergence can protect soybeans from Canada goose depredation

    Application Strategy for an Anthraquinone-Based Repellent and the Protection of Soybeans from Canada Goose Depredation

    Get PDF
    Agricultural crops can sustain extensive damage caused by Canada geese (Branta canadensis) when these crops are planted near wetlands or brood-rearing sites. From 2000 to 2015, South Dakota Game, Fish and Parks spent \u3e$5.6 million to manage damages caused by Canada geese to agricultural crops (primarily soybeans) in South Dakota, USA. For the purpose of developing a repellent application strategy for nonlethal goose damage management, we comparatively evaluated the width of anthraquinone applications (i.e., 9.4 L Flight Control® Plus goose repellent/ha [active ingredient: 50% 9,10-anthraquinone] at 0–36 m versus 0–73 m perpendicular to the edge of wetlands in 2014), the timing of the first repellent application (i.e., 9.4 L Flight Control Plus goose repellent/ha at 50% versus 75% seedling emergence in 2015), the yield of soybeans (Glycine max) within repellent-treated and untreated subplots, and anthraquinone chemical residues in Day County, South Dakota. Soybean yield was greater in subplots 73 m from the water’s edge than that in the 36-m subplots (P \u3c 0.02). Among subplots first sprayed at 50% seedling emergence, soybean yield was greater at 73 m and 82 m than that at 36 m (P \u3c 0.005). In contrast, we observed no difference in yield at 36 m, 73 m, or 82 m in the subplots first sprayed at 72% seedling emergence (P \u3e 0.09). We therefore conclude that goose damages were effectively managed in subplots first sprayed at 72% seedling emergence. Anthraquinone residues averaged 674 and 629 ppm anthraquinone upon the first application of the repellent (June to July), 22 and 35 ppm anthraquinone in the mid-season hay (August to September), and 36 and 28 ppb anthraquinone in the harvested seed (October to November) in 2014 and 2015, respectively. Our results suggest that a 73-m bandwidth of anthraquinone-based repellents first applied at approximately 72% or 65–85% seedling emergence can protect soybeans from Canada goose depredation

    Classic empirical, micro-based studies include MaCurdy

    Get PDF
    Abstract We examine the effect of the presence of learning-by-doing (LBD) on estimates of individuals' intertemporal elasticity of substitution (IES ). Using a simple model, we show that if wages increase with experience, as evidence suggests, then wages are a function of past labor supply decisions. This violates the exogeneity assumption required for standard estimations, which are based on the responsiveness of labor supply to transitory variation in wages, to be consistent. Using a large data set of the daily labor supply decisions of Florida lobster fishermen, we show that wage elasticity estimates are consistent with a model of labor supply in which work today leads to higher future wages through LBD. We estimate an average bias in the estimated IES of 1.6 and a maximal bias of 2.7 associated with ignoring LBD. I Introduction A large literature is devoted to identifying the intertemporal elasticity of substitution (IES ) in labor supply. By and large, empirical, micro-based studies on this topic assume exogenously given wages and derive small, marginally significant estimates of the IES, leading much of the profession to conclude that labor supply elasticities are small. 1 However, evidence suggests that wages increase with work experience, which implies endogenous wage formation. 2 This paper empirically examines the extent to which ignoring this type of endogeneity biases estimates of the IES downward. When wages grow with work experience, the marginal return to work today is not simply today's wage rate. It also includes the marginal increase in the present value of all futur

    Consumption of foods by young children with diagnosed campylobacter infection - a pilot case-control study

    Get PDF
    Objective: To determine whether parentally reported habitual intake of specific foods differed between children with diagnosed Campylobacter jejuni infection and children of a comparison group without diagnosed infection. Design, setting and subjects: Information was collected from the parents or primary caregivers of South Australian children aged 1–5 years with diagnosed C. jejuni (cases, n = 172) and an age- and gender-matched group of uninfected children (controls, n = 173). Frequency of consumption of 106 food and drink items was determined for the preceding two months by food-frequency questionnaire. Four children in the control group had recorded diarrhoeal episodes during the assessment period and were excluded, so 169 responses were evaluated for this group. Information was gathered on possible confounders including socio-economic status. Response frequencies were classified into three levels of consumption (rarely, weekly or daily) and statistical comparison was made by frequency of consumption of foods versus the ‘rarely’ classification for cases and controls, respectively. Results: Frequency of consumption of most foods, including starchy foods and fruits and vegetables, did not differ between cases and controls. However, reported consumption of eight food items (block and processed cheese (slices and spread), salami/fritz (a form of processed sausage), chicken nuggets, pasteurised milk, fish (canned or fresh) and hot French fries) was significantly higher by controls. Conclusions: The hypothesis that reported consumption of starchy foods was lower by cases than by controls was not supported by the data. However, consumption of some processed and unprocessed foods was higher by controls. Some of these foods have established bactericidal actions in vitro that may indicate a possible mechanism for this apparent protection

    Late Quaternary loess in northeastern Colorado: Part I—Age and paleoclimatic significance

    Get PDF
    Loess in eastern Colorado covers an estimated 14,000 km2, and is the westernmost part of the North American midcontinent loess province. Stratigraphic studies indicate there were two periods of loess deposition in eastern Colorado during late Quaternary time. The first period spanned ca. 20,000 to 12,000 14C yr B.P. (ca. 20–14 ka) and correlates reasonably well with the culmination and retreat of Pinedale glaciers in the Colorado Front Range during the last glacial maximum. The second period of loess deposition occurred between ca. 11,000 and 9,000 14C yr B.P. This interval may be Holocene or may correlate with a hypothesized Younger Dryas glacial advance in the Colorado Front Range. Sedimentologic, mineralogic, and geochemical data indicate that as many as three sources could have supplied loess in eastern Colorado. These sources include glaciogenic silt (derived from the Colorado Front Range) and two bedrock sources, volcaniclastic silt from the White River Group, and clays from the Pierre Shale. The sediment sources imply a generally westerly paleowind during the last glacial maximum. New carbon isotope data, combined with published faunal data, indicate that the loess was probably deposited on a cool steppe, implying a last glacial maximum July temperature depression, relative to the present, of at least 5–6 °C. Overall, loess deposition in eastern Colorado occurred mostly toward the end of the last glacial maximum, under cooler and drier conditions, with generally westerly winds from more than one source

    The Propeptide Binding Site of the Bovine γ-Glutamyl Carboxylase

    Get PDF
    gamma-Glutamyl carboxylase is an integral membrane protein required for the posttranslational modification of vitamin K-dependent proteins. The main recognition between the enzyme and its substrates is through an 18-amino acid propeptide. It has been reported that this binding site resides in the amino-terminal third of the gamma-glutamyl carboxylase molecule (Yamada, M., Kuliopulos, A., Nelson, N. P., Roth, D. A., Furie, B., Furie, B. C., and Walsh, C. T. (1995) Biochemistry 34, 481-489). In contrast, we found the binding site in the carboxyl half of the gamma-glutamyl carboxylase. We show that the carboxylase may be cleaved by trypsin into an amino-terminal 30-kDa and a carboxyl-terminal 60-kDa fragment joined by a disulfide bond(s), and the propeptide binds to the 60-kDa fragment. The sequence of the amino terminus of the 60-kDa fragment reveals that the primary trypsin-sensitive sites are at residues 349 and 351. Furthermore, the tryptic fragment that cross-links to the propeptide also reacts with an antibody specific to the carboxyl portion of the gamma-glutamyl carboxylase. In addition, cyanogen bromide cleavage of bovine gamma-glutamyl carboxylase cross-linked to the peptide comprising residues TVFLDHENANKILNRPKRY of human factor IX yields a cross-linked fragment of 16 kDa from the carboxyl half of the molecule, the amino-terminal sequence of which begins at residue 438. Thus, the propeptide binding site lies carboxyl-terminal to residue 438 and is predicted to be in the lumen of the endoplasmic reticulum
    • …
    corecore