1,975 research outputs found
Birth Cohort Differences in Features of Antisocial Alcoholism among Men and Women
Background: This study examines the relations between birth cohort, gender, and family history of alcohol problems on alcohol dependence, and on the endorsement of alcohol abuse/dependence symptoms related to antisocial behavior. Methods: Men (n = 1365) and women (n = 625) were recruited from the community, hospitals, and other treatment sites and were given a structured diagnostic interview. Data were analyzed by using logistic regression. Results: Age of first regular alcohol use was lower in more recent birth cohorts for both men and women, with those born in the most recent cohort reporting earliest regular use. The decline across cohort was more dramatic in women than in men. For those participants with a diagnosis of alcohol dependence, being born in a more recent cohort was associated with increased risk of dependence onset before age 25. Among those participants with onset of alcohol dependence before age 25 (nmen = 400; nwomen = 51), being born in a more recent cohort was associated with increased risk of fights while drinking, police involvement, and drunk driving trouble as well as with increased risk for a diagnosis of abuse or dependence on another drug. Conclusions: These results suggest that the prevalence of antisocial alcoholism may be increasing for both men and women. These data exemplify how societal change may affect expression of underlying vulnerability for traits thought to be genetically influenced
Topographic roughness as a signature of the emergence of bedrock in eroding landscapes
Rock is exposed at the Earth surface when rates of erosion locally exceed
rates of soil production. The thinning of soils and emergence of bedrock has
implications spanning geomorphology, ecology and hydrology. Soil-mantled
hillslopes are typically shaped by diffusion-like sediment transport
processes that act to smooth topography through time, generating the
familiar smooth, convex hillslope profiles that are common in low relief
landscapes. Other processes, however, can roughen the landscape. Bedrock
emergence can produce rough terrain; in this contribution we exploit the
contrast between rough patches of bedrock outcrop and smooth, diffusion-dominated soil to detect bedrock outcrops. Specifically, we demonstrate that
the local variability of surface normal vectors, measured from 1 m resolution
airborne LiDAR data, can be used as a topographic signature to
identify areas within landscapes where rock exposure is present. We then use
this roughness metric to investigate the transition from soil-mantled to
bedrock hillslopes as erosion rates increase in two transient landscapes,
Bald Rock Basin, which drains into the Middle Fork Feather River,
California, and Harrington Creek, a tributary of the Salmon River, Idaho.
Rather than being abrupt, as predicted by traditional soil production
models, in both cases the transition from fully soil-mantled to bedrock
hillslopes is gradual and spatially heterogeneous, with rapidly eroding
hillslopes supporting a patchwork of bedrock and soil that is well
documented by changes in topographic roughness, highlighting the utility of
this metric for testing hypotheses concerning the emergence of bedrock and
adding to a growing body of evidence that indicates the persistence of
partial soil mantles in steep, rapidly eroding landscapes
Isolation, Characterization, and Mapping of a Human Acid β-Galactosidase cDNA
A λgt11 human testicular cDNA library was screened with degenerate oligonucleotide probe mixtures based on amino acid sequence data generated from cyanogen bromide fragments and tryptic fragments of purified human β-galactosidase.Six positive clones were identified after screening 2 x 106 plaques. The sequences of these six clones were determined and found to be derived from two different cDNAs. The sequence of the longest of these cDNAs is nearly identical to that recently determined by Oshima et al. (1988). It codes for a 76-kD protein and all 11 peptides that were generated from the purified enzyme. The second clone is shorter by 393 bp in the central portion of the coding region. Analysis by Northern blotting revealed the presence of a single mRNA species of 2.45 kb in lymphoblasts and testicular tissue. It is deduced from the amino acid sequence data that proteolytic processing of the precursor form of β-galactosidase must occur by cleavage in the carboxy-terminal portion of the polypeptide perhaps around amino acid 530 at a uniquely hydrophilic sequence. Using a probe generated from the 3\u27 region of the cDNA, we have mapped the locus coding for human β-galactosidase to chromosome 3p21-3pter
The early Neolithic of Iraqi Kurdistan: current research at Bestansur, Shahrizor Plain
Human communities made the transition from hunter-foraging to more sedentary agriculture and herding at multiple locations across Southwest Asia through the Early Neolithic period (ca. 10,000-7000 cal. BC). Societies explored strategies involving increasing management and development of plants, animals, materials, technologies, and ideologies specific to each region whilst sharing some common attributes. Current research in the Eastern Fertile Crescent is contributing new insights into the Early Neolithic transition and the critical role that this region played. The Central Zagros Archaeological Project (CZAP) is investigating this transition in Iraqi Kurdistan, including at the earliest Neolithic settlement so far excavated in the region. In this article, we focus on results from ongoing excavations at the Early Neolithic site of Bestansur on the Shahrizor Plain, Sulaimaniyah province, in order to address key themes in the Neolithic transition
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