1,734 research outputs found

    Preliminary Investigation of the Little Sioux River Valley

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    The purpose of this paper is to describe the aerial extent, thickness, and nature of the materials that comprise the modern alluvium and terrace sediments of the Little Sioux River valley. This paper is part of a study conducted in the spring and summer of 1962 which was concerned with the alluvial morphology and engineering properties of the deposits within the valley. This research was supported by the Iowa Engineering Experiment Station and Department of Geology, Iowa State University

    Occurrence of the Waxy Alleles \u3ci\u3ewxa\u3c/i\u3e and \u3ci\u3ewxb\u3c/i\u3e in Waxy Sorghum Plant Introductions and Their Effect on Starch Thermal Properties

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    The existence of two waxy alleles, wxa associated with no detectable granule bound starch synthase (GBSS) and wxb associated with apparently inactive GBSS, was recently reported in sorghum [Sorghum bicolor (L.) Moench]. In this paper, the occurrence of the wxa and wxb alleles in the USDA-ARS photoperiod-insensitive sorghum collection was determined, and the effects of the wxa and wxballeles on thermal properties of sorghum starch (gelatinization temperatures and energy requirements) measured by differential scanning calorimetry. Of the 51 purported waxy accessions examined, 14 tested positive for presence of amylose by iodine staining and were considered to be previously misclassified wild type lines. Nine accessions were mixed for presence or absence of amylose. Twenty-four of the 28 accessions confirmed to be waxy by negative iodine staining for amylose had no detectable GBSS using sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) (wxa), and four were show to contain GBSS (wxb). Mean gelatinization onset, peak, and end temperatures were significantly lower for wild-type than either of the two waxy genotypes. Mean gelatinization onset temperature was slightly higher for waxy-GBSS+ genotypes than waxy-GBSS− genotypes. Mean gelatinization end temperature was slightly higher for waxy-GBSS− genotypes than waxy-GBSS+ genotypes. Significant genetic variation was observed within genotypic classes, suggesting influence of additional modifier genes affecting sorghum starch structure or micro-environmental effects

    Occurrence of the Waxy Alleles \u3ci\u3ewxa\u3c/i\u3e and \u3ci\u3ewxb\u3c/i\u3e in Waxy Sorghum Plant Introductions and Their Effect on Starch Thermal Properties

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    The existence of two waxy alleles, wxa associated with no detectable granule bound starch synthase (GBSS) and wxb associated with apparently inactive GBSS, was recently reported in sorghum [Sorghum bicolor (L.) Moench]. In this paper, the occurrence of the wxa and wxb alleles in the USDA-ARS photoperiod-insensitive sorghum collection was determined, and the effects of the wxa and wxballeles on thermal properties of sorghum starch (gelatinization temperatures and energy requirements) measured by differential scanning calorimetry. Of the 51 purported waxy accessions examined, 14 tested positive for presence of amylose by iodine staining and were considered to be previously misclassified wild type lines. Nine accessions were mixed for presence or absence of amylose. Twenty-four of the 28 accessions confirmed to be waxy by negative iodine staining for amylose had no detectable GBSS using sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) (wxa), and four were show to contain GBSS (wxb). Mean gelatinization onset, peak, and end temperatures were significantly lower for wild-type than either of the two waxy genotypes. Mean gelatinization onset temperature was slightly higher for waxy-GBSS+ genotypes than waxy-GBSS− genotypes. Mean gelatinization end temperature was slightly higher for waxy-GBSS− genotypes than waxy-GBSS+ genotypes. Significant genetic variation was observed within genotypic classes, suggesting influence of additional modifier genes affecting sorghum starch structure or micro-environmental effects

    Brief of Defendant - Appellees in \u3cem\u3eEnvironmental Defense Fund v. TVA\u3c/em\u3e, No. 73-8174

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    Brief of the defendants/appellees in the case of Environmental Defense Fund, et al. v. TVA, et al. in the United States Court of Appeals for the Sixth Circuit

    Estrogen Receptors are Present in Neocortical Transplants

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    Fetal neocortical tissue was grafted into neocortical lesion cavities made in newborn rats. After two weeks survival, in vitro binding of [3H]- estradiol to cytosolic preparations provided evidence of estrogen receptors within the transplants. The observed high levels correspond to previous work demonstrating elevated estrogen receptor levels during the first postnatal week in the rat cerebral cortex

    Inverse ac Josephson Effect for a Fluxon in a Long Modulated Junction

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    We analyze motion of a fluxon in a weakly damped ac-driven long Josephson junction with a periodically modulated maximum Josephson current density. We demonstrate both analytically and numerically that a pure {\it ac} bias current can drive the fluxon at a {\it resonant} mean velocity determined by the driving frequency and the spatial period of the modulation, provided that the drive amplitude exceeds a certain threshold value. In the range of strongly ``relativistic'' mean velocities, the agreement between results of a numerical solution of the effective (ODE) fluxon equation of motion and analytical results obtained by means of the harmonic-balance analysis is fairly good; morever, a preliminary PDE result tends to confirm the validity of the collective-coordinate (PDE-ODE) reduction. At nonrelativistic mean velocities, the basin of attraction, in position-velocity space, for phase-locked solutions becomes progressively smaller as the mean velocity is decreased.Comment: 15 pages, 26 kbytes, of text in plain LaTeX. A uuencoded, Z-compressed tar archive, 21 kbytes, containing 3 PostScript, [email protected], [email protected], [email protected]

    Cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH) mutations associated with the domestic cat AB blood group

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    <p>Abstract</p> <p>Background</p> <p>The cat has one common blood group with two major serotypes, blood type A that is dominant to type B. A rare type AB may also be allelic and is suspected to be recessive to A and dominant to B. Cat blood type antigens are defined, N-glycolylneuraminic acid (NeuGc) is associated with type A and N-acetylneuraminic acid (NeuAc) with type B. The enzyme <it>cytidine monophospho-N-acetylneuraminic acid hydroxylase </it>(<it>CMAH</it>) determines the sugar bound to the red cell by converting NeuAc to NeuGc. Thus, mutations in <it>CMAH </it>may cause the A and B blood types.</p> <p>Results</p> <p>Genomic sequence of <it>CMAH </it>from eight cats and the cDNA of four cats representing all blood types were analyzed to identify causative mutations. DNA variants consistent with the blood types were genotyped in over 200 cats. Five SNPs and an indel formed haplotypes that were consistent with each blood type.</p> <p>Conclusion</p> <p>Mutations in type B cats likely disrupt the gene function of <it>CMAH</it>, leading to a predominance of NeuAc. Type AB concordant variants were not identified, however, cDNA species suggest an alternative allele that activates a downstream start site, leading to a CMAH protein that would be altered at the 5' region. The cat AB blood group system is proposed to be designated by three alleles, <it>A </it>> <it>a</it><sup><it>ab </it></sup>> <it>b</it>. The <it>A </it>and <it>b CMAH </it>alleles described herein can distinguish type A and type B cats without blood sample collections. <it>CMAH </it>represents the first blood group gene identified outside of non-human primates and humans.</p

    EU-Rotate_N – a decision support system – to predict environmental and economic consequences of the management of nitrogen fertiliser in crop rotations

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    A model has been developed which assesses the economic and environmental performance of crop rotations, in both conventional and organic cropping, for over 70 arable and horticultural crops, and a wide range of growing conditions in Europe. The model, though originally based on the N_ABLE model, has been completely rewritten and contains new routines to simulate root development, the mineralisation and release of nitrogen (N) from soil organic matter and crop residues, and water dynamics in soil. New routines have been added to estimate the effects of sub-optimal rates of N and spacing on the marketable outputs and gross margins. The model provides a mechanism for generating scenarios to represent a range of differing crop and fertiliser management strategies which can be used to evaluate their effects on yield, gross margin and losses of nitrogen through leaching. Such testing has revealed that nitrogen management can be improved and that there is potential to increase gross margins whilst reducing nitrogen losses

    Tomographic image of melt storage beneath Askja Volcano, Iceland using local microseismicity

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    We use P wave and S wave arrivals from microseismic earthquakes to construct 3-D tomographic Vp and Vs images of the magma storage region beneath Askja's central volcano in the Northern Volcanic Zone of Iceland. A distinctive ellipsoidal low-velocity anomaly, with both Vp and Vsvelocities 8-12% below the background, is imaged at 6-11 km depth beneath the caldera. The presence of a shallow magma chamber is corroborated by geodetic and gravity studies. The small Vp/Vs anomaly suggests a lack of pervasive melt. We interpret this anomaly as a region of multiple sills, some frozen but hot, others containing partial melt. A second, smaller low-velocity anomaly beneath the main magma storage region may represent a magma migration pathway. This interpretation is supported by the close proximity to the anomaly of clusters of deep, magmatically induced earthquakes. However, the location and shape of this deep anomaly are poorly constrained by the current data set
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