5,135 research outputs found

    "Capital Intensity and U.S. Country Population Growth during the Late Nineteenth Century"

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    The United States witnessed substantial growth in manufacturing and urban populations during the last half of the nineteenth century. To date, no convincing evidence has been presented to explain the shift in population to urban areas. We find evidence that capital intensity, particularly new capital in the form of steam horsepower, played a significant role in drawing labor into counties and by inference into urban areas. This provides support for the hypothesis that the locational decisions of manufacturers and their placement of capital in urban areas fueled urban growth in the nineteenth century.urbanization, capital intensity, regional population growth, technological change

    Identification of two distinct intron elements involved in alternative splicing of beta-tropomyosin pre-mRNA

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    The rat beta-tropomyosin gene encodes two isoforms, termed skeletal muscle beta-tropomyosin and fibroblast last tropomyosim 1 (TM-1), via an alternative RNA processing mechanism. The gene contains 11 exons. Exons 1-5 and exons 8 and 9 are common to all mRNAs expressed from the gene. Exons 6 and 11 are used in fibroblasts, as well as smooth muscle, whereas exons 7 and 10 are used only in skeletal muscle. In the present studies we focused on the mutually exclusive internal alternative splice choice involving exon 6 (fibroblast-type splice) and exon 7 (skeletal muscle-type splice). We have identified two distinct elements in the intron, upstream of exon 7, involved in splice site selection. The first element is comprised of a polypyrimidine tract located 89-143 nucleotides upstream of the 3' splice site, which specifies the location of the lariat branchpoints used, 144-153 nucleotides upstream of exon 7. The 3' splice site AG dinucleotide has no role in selection of these branchpoints. The second element is comprised of intron sequences located between the polypyrimidine tract and the 3' splice site of exon 7. It contains an important determinant in alternative splice site selection, because deletion of these sequences results in the use of the skeletal muscle-specific exon in nonmuscle cells. We propose that the use of lariat branchpoints located far upstream from a 3' splice site may be a general feature of some alternatively excised introns, reflecting the presence of regulatory sequences located between the lariat branch site and the 3' splice site. The data also indicate that alternative splicing of the rat beta-tropomyosin gene is regulated by a somewhat different mechanism from that described for rat alpha-tropomyosin gene and the transformer-2 gene of Drosophila melanogaster

    The Effects of Mindfulness-Based Stress Reduction on Trauma in Victims of Gun Violence:a Pilot Study

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    OBJECTIVES: Gun violence is a significant problem in the United States of America. Gun violence produces lifelong psychological adversity, trauma, and grief. In the face of this epidemic, efficacious therapies that assuage gun violence-based trauma and negative health are lacking. METHODS: The proposed, longitudinal pilot experiment examined the effects of an 8-week mindfulness-based stress reduction (MBSR) program on traumatized individuals as a direct consequence of gun violence. Twenty-four victims of gun violence (median age = 53 years; 21 female) completed measures of the primary outcome: trauma. Secondary outcomes were characterized as grief, depression, sleep quality, life satisfaction, and mindfulness. All assessments were administered before, after 5, and 8 weeks of MBSR training. It was hypothesized that trauma and other comorbidities would improve following MBSR. It was also predicted that outcomes would be significantly stronger from baseline to 5 weeks of MBSR training than from 5 to 8 weeks of training. RESULTS: Before MBSR, volunteers exhibited high levels of trauma, depression, sleep difficulty, and grief. Participation in MBSR was associated with improved trauma, depression, sleep difficulty, and life satisfaction. The most pronounced improvements in psychological disposition were exhibited within the first 5 weeks of MBSR. However, these benefits were largely preserved after completion of the course. Importantly, increases in dispositional mindfulness predicted lower trauma, complicated grief, and sleep difficulties. CONCLUSIONS: The present findings should be interpreted with caution because they were derived from an uncontrolled, non-randomized trial. However, said findings suggest that MBSR may reduce trauma and improve overall well-being in gun violence victims

    Homicide in Canada and the crime drop

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    In contrast to the Canadian crime drop of the 1990s, homicide appeared as an anomaly with a peak in the 1970s. Yet previous studies tend to refer only to completed homicides, and here we also include attempts. The resulting trend is remarkably similar to that in Canadian property crime for five decades. This seems unlikely to be a coincidence and we speculate about a causal link

    Literature Lab: a method of automated literature interrogation to infer biology from microarray analysis

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    <p>Abstract</p> <p>Background</p> <p>The biomedical literature is a rich source of associative information but too vast for complete manual review. We have developed an automated method of literature interrogation called "Literature Lab" that identifies and ranks associations existing in the literature between gene sets, such as those derived from microarray experiments, and curated sets of key terms (i.e. pathway names, medical subject heading (MeSH) terms, etc).</p> <p>Results</p> <p>Literature Lab was developed using differentially expressed gene sets from three previously published cancer experiments and tested on a fourth, novel gene set. When applied to the genesets from the published data including an <it>in vitro </it>experiment, an <it>in vivo </it>mouse experiment, and an experiment with human tumor samples, Literature Lab correctly identified known biological processes occurring within each experiment. When applied to a novel set of genes differentially expressed between locally invasive and metastatic prostate cancer, Literature Lab identified a strong association between the pathway term "FOSB" and genes with increased expression in metastatic prostate cancer. Immunohistochemistry subsequently confirmed increased nuclear FOSB staining in metastatic compared to locally invasive prostate cancers.</p> <p>Conclusion</p> <p>This work demonstrates that Literature Lab can discover key biological processes by identifying meritorious associations between experimentally derived gene sets and key terms within the biomedical literature.</p

    Feeding Concentrate Formulated With Native Irish Feed Ingredients and a Low Crude Protein Content to Grazing Dairy Cows Has No Effect on Milk Production or Milk Composition

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    Improving nitrogen use efficiency (NUE) and feeding native feed ingredients offers potential to improve the environmental sustainability of dairy production. However, improving NUE is a key challenge in grass-based systems due to high crude protein (CP) levels in grass and low nitrogen retention by dairy cows. In addition, concentrate feed typically contains imported feed ingredients which contribute to increased carbon footprint. Therefore, the objective of this study was to investigate the effect of concentrate CP level and ingredient source on milk production and composition. Forty-two mixed-parity Holstein-Friesian cows were blocked on parity and balanced on days in milk (DIM), milk production, BCS and Economic Breeding Index (EBI; n=14). Cows grazed full time and were offered a basal diet of perennial ryegrass pasture (average 17 kg DM/cow/day) and fed one of three concentrate supplements at varying levels according to DIM during the main grazing season (153 days). The concentrate treatments (T) were: T1) 14% CP concentrate formulated with non-native ingredients, T2) 12% CP concentrate formulated with non-native ingredients or T3) 12% CP concentrate formulated with native ingredients. Reducing the CP level or formulating with native feed ingredients did not alter milk or milk solids yield (T1: 25.7 kg/day, 2.11 kg/day; T2: 25.3 kg/day, 2.06 kg/day; T3: 24.9 kg/day, 2.01 kg/day respectively). Similarly, no effect of treatment was observed for milk fat or protein percentage (T1: 4.40 %, 3.66 %; T2: 4.44 %, 3.64 %; T3: 4.37 %, 3.66 %, respectively). The results of this study highlight that the sustainability of grass-based dairy may be improved by using a low concentrate CP content (12%) in addition to offering concentrate feed based on native feed ingredients which can result in similar performance to that of dairy cows offered a 14% CP concentrate or a concentrate based on imported ingredients respectively
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