203 research outputs found
Personalilty characteristics, locus of control, and life stress as factors in relapse and recovery in a substance abuse sample.
A set of psychometric tests were administered to a sample of individuals accessing addiction services. This study sought to 1) explore personality, locus of control, and life stress in relation to the duration of abstinence from substance abuse, and 2) determine if there were any aspects of personality that were common among those with either long or short bouts of achieved sobriety. Seventy-two chemically dependent men and women in a Northern Ontario, Canada sample participated in the study. Few differences were found between sobriety groups. Statistically significant gender differences were found on the MMPI-Repression scale and the MMPI-Masculine/Feminine scales. Significant personality differences were also found between individuals who were receiving mental health related prescription medication on the MMPI scales of Hypochondriasis, Depression, Hysteria, Psychopathic Deviant, and Psychasthenia. Further significant differences were found between individuals who had a mental health diagnosis on the MMPI scales of Hypochondriasis, Depression, Hysteria, Psychopathic Deviant, Paranoia, Psychasthenia, Schizophrenia, and Anxiety.Master's These
Charters without Lotteries: Testing Takeovers in New Orleans and Boston
Charter takeovers are traditional public schools restarted as charter schools. We develop a grandfathering instrument for takeover attendance that compares students at schools designated for takeover with a matched sample of students attending similar schools not yet taken over. Grandfathering estimates from New Orleans show substantial gains from takeover enrollment. In Boston, grandfathered students see achievement gains at least as large as the gains for students assigned charter seats in lotteries. A non-charter Boston turnaround intervention that had much in common with the takeover strategy generated gains as large as those seen for takeovers, while other more modest turnaround interventions yielded smaller effects.Institute of Education Sciences (U.S.) (Award R305A120269)National Science Foundation (U.S.) (award SES-1426541)Laura and John Arnold Foundatio
Practical Interests, Relevant Alternatives, and Knowledge Attributions: an Empirical Study
In defending his interest-relative account of knowledge, Jason Stanley relies heavily on intuitions about several bank cases. We experimentally test the empirical claims that Stanley seems to make concerning our common-sense intuitions about these cases. Additionally, we test the empirical claims that Jonathan Schaffer seems to make, regarding the salience of an alternative, in his critique of Stanley. Our data indicate that neither raising the possibility of error nor raising stakes moves most people from attributing knowledge to denying it. However, the raising of stakes (but not alternatives) does affect the level of confidence people have in their attributions of knowledge. We argue that our data impugn what both Stanley and Schaffer claim our common-sense judgments about such cases are
Population structure and plumage polymorphism: The intraspecific evolutionary relationships of a polymorphic raptor, Buteo jamaicensis harlani
<p>Abstract</p> <p>Background</p> <p>Phenotypic and molecular genetic data often provide conflicting patterns of intraspecific relationships confounding phylogenetic inference, particularly among birds where a variety of environmental factors may influence plumage characters. Among diurnal raptors, the taxonomic relationship of <it>Buteo jamaicensis harlani </it>to other <it>B. jamaicensis </it>subspecies has been long debated because of the polytypic nature of the plumage characteristics used in subspecies or species designations.</p> <p>Results</p> <p>To address the evolutionary relationships within this group, we used data from 17 nuclear microsatellite loci, 430 base pairs of the mitochondrial control region, and 829 base pairs of the melanocortin 1 receptor (<it>Mc1r</it>) to investigate molecular genetic differentiation among three <it>B. jamaicensis </it>subspecies (<it>B. j. borealis</it>, <it>B. j. calurus</it>, <it>B. j. harlani</it>). Bayesian clustering analyses of nuclear microsatellite loci showed no significant differences between <it>B. j. harlani </it>and <it>B. j. borealis</it>. Differences observed between <it>B. j. harlani </it>and <it>B. j. borealis </it>in mitochondrial and microsatellite data were equivalent to those found between morphologically similar subspecies, <it>B. j. borealis </it>and <it>B. j. calurus</it>, and estimates of migration rates among all three subspecies were high. No consistent differences were observed in <it>Mc1r </it>data between <it>B. j. harlani </it>and other <it>B. jamaicensis </it>subspecies or between light and dark color morphs within <it>B. j. calurus</it>, suggesting that <it>Mc1r </it>does not play a significant role in <it>B. jamaicensis </it>melanism.</p> <p>Conclusions</p> <p>These data suggest recent interbreeding and gene flow between <it>B. j. harlani </it>and the other <it>B. jamaicensis </it>subspecies examined, providing no support for the historical designation of <it>B. j. harlani </it>as a distinct species.</p
Mechanistic characterization of the 5â˛-triphosphate-dependent activation of PKR: Lack of 5â˛-end nucleobase specificity, evidence for a distinct triphosphate binding site, and a critical role for the dsRBD
The protein kinase PKR is activated by RNA to phosphorylate eIF-2Îą, inhibiting translation initiation. Long dsRNA activates PKR via interactions with the dsRNA-binding domain (dsRBD). Weakly structured RNA also activates PKR and does so in a 5â˛-triphosphate (ppp)âdependent fashion, however relatively little is known about this pathway. We used a mutant T7 RNA polymerase to incorporate all four triphosphate-containing nucleotides into the first position of a largely single-stranded RNA and found absence of selectivity, in that all four transcripts activate PKR. Recognition of 5â˛-triphosphate, but not the nucleobase at the 5â˛-most position, makes this RNA-mediated innate immune response sensitive to a broad array of viruses. PKR was neither activated in the presence of Îł-GTP nor recognized NTPs other than ATP in activation competition and ITC binding assays. This indicates that the binding site for ATP is selective, which contrasts with the site for the 5Ⲡend of ppp-ssRNA. Activation experiments reveal that short dsRNAs compete with 5â˛-triphosphate RNAs and heparin for activation, and likewise gel-shift assays reveal that activating 5â˛-triphosphate RNAs and heparin compete with short dsRNAs for binding to PKR's dsRBD. The dsRBD thus plays a critical role in the activation of PKR by ppp-ssRNA and even heparin. At the same time, cross-linking experiments indicate that ppp-ssRNA interacts with PKR outside of the dsRBD as well. Overall, 5â˛-triphosphate-containing, weakly structured RNAs activate PKR via interactions with both the dsRBD and a distinct triphosphate binding site that lacks 5â˛-nucleobase specificity, allowing the innate immune response to provide broad-spectrum protection from pathogens
Banner News
https://openspace.dmacc.edu/banner_news/1283/thumbnail.jp
Structural Characterization of Cuta- and Tusavirus: Insight into Protoparvoviruses Capsid Morphology
Several members of the Protoparvovirus genus, capable of infecting humans, have been recently discovered, including cutavirus (CuV) and tusavirus (TuV). To begin the characterization of these viruses, we have used cryo-electron microscopy and image reconstruction to determine their capsid structures to ~2.9 Ă
resolution, and glycan array and cell-based assays to identify glycans utilized for cellular entry. Structural comparisons show that the CuV and TuV capsids share common features with other parvoviruses, including an eight-stranded anti-parallel β-barrel, depressions at the icosahedral 2-fold and surrounding the 5-fold axes, and a channel at the 5-fold axes. However, the viruses exhibit significant topological differences in their viral protein surface loops. These result in three separated 3-fold protrusions, similar to the bufaviruses also infecting humans, suggesting a host-driven structure evolution. The surface loops contain residues involved in receptor binding, cellular trafficking, and antigenic reactivity in other parvoviruses. In addition, terminal sialic acid was identified as the glycan potentially utilized by both CuV and TuV for cellular entry, with TuV showing additional recognition of poly-sialic acid and sialylated Lewis X (sLeXLeXLeX) motifs reported to be upregulated in neurotropic and cancer cells, respectively. These structures provide a platform for annotating the cellular interactions of these human pathogens
Structural Characterization of Cuta- and Tusavirus: Insight into Protoparvoviruses Capsid Morphology
Several members of the Protoparvovirus genus, capable of infecting humans, have been recently discovered, including cutavirus (CuV) and tusavirus (TuV). To begin the characterization of these viruses, we have used cryo-electron microscopy and image reconstruction to determine their capsid structures to ~2.9 Ă
resolution, and glycan array and cell-based assays to identify glycans utilized for cellular entry. Structural comparisons show that the CuV and TuV capsids share common features with other parvoviruses, including an eight-stranded anti-parallel β-barrel, depressions at the icosahedral 2-fold and surrounding the 5-fold axes, and a channel at the 5-fold axes. However, the viruses exhibit significant topological differences in their viral protein surface loops. These result in three separated 3-fold protrusions, similar to the bufaviruses also infecting humans, suggesting a host-driven structure evolution. The surface loops contain residues involved in receptor binding, cellular trafficking, and antigenic reactivity in other parvoviruses. In addition, terminal sialic acid was identified as the glycan potentially utilized by both CuV and TuV for cellular entry, with TuV showing additional recognition of poly-sialic acid and sialylated Lewis X (sLeXLeXLeX) motifs reported to be upregulated in neurotropic and cancer cells, respectively. These structures provide a platform for annotating the cellular interactions of these human pathogens
Comparison of prestellar core elongations and large-scale molecular cloud structures in the Lupus 1 region
Turbulence and magnetic fields are expected to be important for regulating molecular cloud formation and evolution. However, their effects on sub-parsec to 100 parsec scales, leading to the formation of starless cores, are not well understood. We investigate the prestellar core structure morphologies obtained from analysis of the Herschel-SPIRE 350 mum maps of the Lupus I cloud. This distribution is first compared on a statistical basis to the large-scale shape of the main filament. We find the distribution of the elongation position angle of the cores to be consistent with a random distribution, which means no specific orientation of the morphology of the cores is observed with respect to the mean orientation of the large-scale filament in Lupus I, nor relative to a large-scale bent filament model. This distribution is also compared to the mean orientation of the large-scale magnetic fields probed at 350 mum with the Balloon-borne Large Aperture Telescope for Polarimetry during its 2010 campaign. Here again we do not find any correlation between the core morphology distribution and the average orientation of the magnetic fields on parsec scales. Our main conclusion is that the local filament dynamics---including secondary filaments that often run orthogonally to the primary filament---and possibly small-scale variations in the local magnetic field direction, could be the dominant factors for explaining the final orientation of each core
- âŚ