227 research outputs found

    Effects of migration on the open-country population of Iowa, 1950-61

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    Accelerating mobility is a characteristic of modern society. As technological revolution reshuffles occupational priorities, more people find it necessary to change jobs and often to change residences as well. Although discussions of high mobility usually refer to the urban population, there is growing evidence that rural people constitute a substantial part of the mass movement of population that occurs each year. The census count of the farm population of Iowa in 1960 was 662,239, compared with 782,650 in 1950. Thus, there were about 120,000 fewer people in the farm population of the state in 1960 than there were in 1950. Part of this reduction is only an apparent one resulting from a change of definition between 1950 and 1960 of the farm population, but there can be little doubt that there was a real and substantial decline in Iowa\u27s farm population. At the same time, the rural nonfarm population increased

    The impact of Saharan dust and black carbon on albedo and long-term mass balance of an Alpine glacier

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    Light-absorbing impurities in snow and ice control glacier melt as shortwave radiation represents the main component of the surface energy balance. Here, we investigate the long-term effect of snow impurities, i.e., mineral dust and black carbon (BC), on albedo and glacier mass balance. The analysis was performed over the period 1914–2014 for two sites on Claridenfirn, Swiss Alps, where an outstanding 100-year record of seasonal mass balance measurements is available. Information on atmospheric deposition of mineral dust and BC over the last century was retrieved from two firn/ice cores of high-alpine sites. A combined mass balance and snow/firn layer model was employed to assess the effects of melt and accumulation processes on the impurity concentration at the surface and thus on albedo and glacier mass balance. Compared to pure snow conditions, the presence of Saharan dust and BC lowered the mean annual albedo by 0.04–0.06 depending on the location on the glacier. Consequently, annual melt was increased by 15–19 %, and the mean annual mass balance was reduced by about 280–490 mm w.e. BC clearly dominated absorption which is about 3 times higher than that of mineral dust. The upper site has experienced mainly positive mass balances and impurity layers were continuously buried whereas at the lower site, surface albedo was more strongly influenced by re-exposure of dust and BC-enriched layers due to frequent years with negative mass balances

    Estimating the Effects of Crop Residue Mulches on Soil Erosion By Water

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    This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

    A Spectral Line Survey from 138.3 to 150.7 GHZ toward Orion-KL

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    We present the results of a spectral line survey from 138.3 to 150.7 GHz toward Orion-KL. The observations were made using the 14 m radio telescope of Taeduk Radio Astronomy Observatory. Typical system temperatures were between 500 and 700 K, with the sensitivity between 0.02−0.060.02 - 0.06 K in units of TA∗\rm T_A^*. A total of 149 line spectra are detected in this survey. Fifty lines have been previously reported, however we find 99 new detections. Among these new lines, 32 are `unidentified', while 67 are from molecular transitions with known identifications. There is no detection of H or He recombination lines. The identified spectra are from a total of 16 molecular species and their isotopic variants. In the range from 138.3 to 150.7 GHz, the strongest spectral line is the J=3-2 transition of CS molecule, followed by transitions of the H2CO\rm H_2CO, CH3OH\rm CH_3OH, CH3CN\rm CH_3CN, and SO2\rm SO_2. Spectral lines from the large organic molecules such as CH3OH\rm CH_3OH, CH3OCH3\rm CH_3OCH_3, HCOOCH3\rm HCOOCH_3, C2H5CN\rm C_2H_5CN and CH3CN\rm CH_3CN are prominent; with 80 % of the identified lines arising from transitions of these molecules. The rotational temperatures and column densities are derived using the standard rotation diagram analysis for CH3OH\rm CH_3OH (13CH3OH\rm ^{13}CH_3OH), HCOOCH3\rm HCOOCH_3, CH3CN\rm CH_3CN and SO2\rm SO_2 with 10∌270K\rm 10\sim 270 K and 0.2∌20×1015cm−2\rm 0.2\sim 20\times 10^{15} cm^{-2}. These estimates are fairly comparable to the values for the same molecule in other frequency regions by other studies.Comment: 10 figures, 2 tex files for a manuscript and tables, accepted to Ap

    Tillage Its Role in Controlling Soil Erosion by Water

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    This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

    1827 Hydrology: Glaciology (1863); 1863 Hydrology: Snow and ice (1827); 3309 Meteorology and Atmospheric Dynamics: Climatology (1620)

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    [1] Over fifty years of cumulative annual mass balance data for several glaciers in the Alps shows similar fluctuations which seem to provide evidence of a common climatic signal. Separate winter and summer mass balance measurements from the Claridenfirn (glacier in Switzerland) since 1914 and the Sarennes glacier (France) since 1949 show that (1) the annual mass balance is primarily driven by the summer mass balance term and (2) melting rate variations with time are very similar for these two glaciers located 290 km apart. The increase in the ablation rate of 0.5 cm w.e. day À1 between the two periods 1954-1981 and 1982-2002 over these two glaciers corresponds to a 20 Wm À2 rise in the energy flux at the glacier surface. These results suggest that a common summer melting rate change may have affected the Alps as a whole. Detailed observations on the Sarennes glacier show that the origin of this strong increase in summer ablation since 1982 is not only a rise in the summer melting rate, but also an increase in the ablation period during the months of September and October

    Follow-up assessment of high-risk newborns in Switzerland

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    Target population High-risk newborns in the context of these guidelines are children who were born very preterm (before 32 weeks gestational age) or children who developed a ypoxic ischaemic encephalopathy (Sarnat grade 2–3) during the first hours of life

    Bi-allelic variants in NAE1 cause intellectual disability, ischiopubic hypoplasia, stress-mediated lymphopenia and neurodegeneration

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    Neddylation has been implicated in various cellular pathways and in the pathophysiology of numerous diseases. We identified four individuals with bi-allelic variants in NAE1, which encodes the neddylation E1 enzyme. Pathogenicity was supported by decreased NAE1 abundance and overlapping clinical and cellular phenotypes. To delineate how cellular consequences of NAE1 deficiency would lead to the clinical phenotype, we focused primarily on the rarest phenotypic features, based on the assumption that these would best reflect the pathophysiology at stake. Two of the rarest features, neuronal loss and lymphopenia worsening during infections, suggest that NAE1 is required during cellular stress caused by infections to protect against cell death. In support, we found that stressing the proteasome system with MG132—requiring upregulation of neddylation to restore proteasomal function and proteasomal stress—led to increased cell death in fibroblasts of individuals with NAE1 genetic variants. Additionally, we found decreased lymphocyte counts after CD3/CD28 stimulation and decreased NF-ÎșB translocation in individuals with NAE1 variants. The rarest phenotypic feature—delayed closure of the ischiopubic rami—correlated with significant downregulation of RUN2X and SOX9 expression in transcriptomic data of fibroblasts. Both genes are involved in the pathophysiology of ischiopubic hypoplasia. Thus, we show that NAE1 plays a major role in (skeletal) development and cellular homeostasis during stress. Our approach suggests that a focus on rare phenotypic features is able to provide significant pathophysiological insights in diseases caused by mutations in genes with pleiotropic effects.</p
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