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This study estimates the relationship between combat exposure and several risky health behaviors: cigarette consumption, binge drinking, and drug use. We find that the U.S. active duty military personnel deployed to combat zones w...
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This study estimates the relationship between combat exposure and several risky health behaviors: cigarette consumption, binge drinking, and drug use. We find that the U.S. active duty military personnel deployed to combat zones with enemy firefight are more likely to subsequently smoke cigarettes, consume alcohol, and use illicit drugs than their counterparts deployed to noncombat operations. Our results suggest that the mental health effects of combat can explain up to two-thirds of the estimated association between combat exposure and risky health behaviors.
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We develop a binomial lattice model of zero-leverage behaviour using a real option on debt issuance. With the option, firms may delay issuance even when debt is feasible and adds value to the firm. We find that firms are more like...
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We develop a binomial lattice model of zero-leverage behaviour using a real option on debt issuance. With the option, firms may delay issuance even when debt is feasible and adds value to the firm. We find that firms are more likely to delay debt issuance when facing shorter debt horizons and longer option horizons. Our results suggest that firms earlier in their life cycle are more likely to be debt-free. This finding is consistent with empirical evidence that young firms are more likely to forgo debt. Our results also suggest that firms unable to access long-term debt markets are more inclined to be free of debt, even if short-term debt issuance is feasible.
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Neuroimaging studies have revealed atypical activation during language and executive tasks in individuals with autism spectrum disorders (ASD). However, the spatiotemporal stages of processing associated with these dysfunctions re...
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Neuroimaging studies have revealed atypical activation during language and executive tasks in individuals with autism spectrum disorders (ASD). However, the spatiotemporal stages of processing associated with these dysfunctions remain poorly understood. Using an anatomically constrained magnetoencephalography approach, we examined event-related theta oscillations during a double-duty lexical decision task that combined demands on lexico-semantic processing and executive functions. Relative to typically developing peers, high-functioning adolescents with ASD had lower performance accuracy on trials engaging selective semantic retrieval and cognitive control. They showed an early overall theta increase in the left fusiform cortex followed by greater activity in the left-lateralized temporal (starting at similar to 250 ms) and frontal cortical areas (after similar to 450 ms) known to contribute to language processing. During response preparation and execution, the ASD group exhibited elevated theta in the anterior cingulate cortex, indicative of greater engagement of cognitive control. Simultaneously increased activity in the ipsilateral motor cortex may reflect a less lateralized and suboptimally organized motor circuitry. Spanning early sensory-specific and late response selection stages, the higher event-related theta responsivity in ASD may indicate compensatory recruitment to offset inefficient lexico-semantic retrieval under cognitively demanding conditions. Together, these findings provide further support for atypical language and executive functions in high-functioning ASD.
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Although age-related memory differences between young and older adults have been well documented, fewer studies have investigated memory changes in middle age. We examined the performance of healthy middle-aged adults (40-55 years...
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Although age-related memory differences between young and older adults have been well documented, fewer studies have investigated memory changes in middle age. We examined the performance of healthy middle-aged adults (40-55 years of age; n = 32) in relation to healthy young (18-25 years of age; n = 57) and older adults (65+ years of age; n = 55) on variations of recognition discriminability (RD) indices derived from the California Verbal Learning Test-Second Edition (CVLT-II). Middle-aged adults performed significantly worse (ps < .05) than young adults on multiple RD indices that incorporate semantically related distractor items, suggesting memory changes in middle age may be associated with increased susceptibility to semantic interference. Moreover, middle-aged adults performed comparably to older adults across all RD indices, indicating the recognition profile of middle-aged adults on RD indices more closely resembles that of older adults than young adults.
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P>Roseophage SIO1 is a lytic marine phage that infects Roseobacter SIO67, a member of the Roseobacter clade of near-shore alphaproteobacteria. Roseophage SIO1 was first isolated in 1989 and sequenced in 2000. We have re-sequenced ...
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P>Roseophage SIO1 is a lytic marine phage that infects Roseobacter SIO67, a member of the Roseobacter clade of near-shore alphaproteobacteria. Roseophage SIO1 was first isolated in 1989 and sequenced in 2000. We have re-sequenced and re-annotated the original isolate. Our current annotation could only assign functions to seven additional open reading frames, indicating that, despite the advances in bioinformatics tools and increased genomic resources, we are still far from being able to translate phage genomic sequences into biological functions. In 2001, we isolated four new strains of Roseophage SIO1 from California near-shore locations. The genomes of all four were sequenced and compared against the original Roseophage SIO1 isolated in 1989. A high degree of conservation was evident across all five genomes; comparisons at the nucleotide level yielded an average 97% identity. The observed differences were clustered in protein-encoding regions and were mostly synonymous. The one strain that was found to possess an expanded host range also showed notable changes in putative tail protein-coding regions. Despite the possibly rapid evolution of phage and the mostly uncharacterized diversity found in viral metagenomic data sets, these findings indicate that viral genomes such as the genome of SIO1-like Roseophages can be stably maintained over ecologically significant time and distance (i.e. over a decade and similar to 50 km).
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Objective: Converging evidence indicates that brain abnormalities in autism spectrum disorder (ASD) involve atypical network connectivity, but few studies have integrated functional with structural connectivity measures. This mult...
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Objective: Converging evidence indicates that brain abnormalities in autism spectrum disorder (ASD) involve atypical network connectivity, but few studies have integrated functional with structural connectivity measures. This multimodal investigation examined functional and structural connectivity of the imitation network in children and adolescents with ASD, and its links with clinical symptoms.
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We examined the effects of gender and work-groups' perceptions of climate for sexual harassment on the relationship between individuals' sexual harassment experiences and job-related outcomes (namely, job satisfaction, affective o...
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We examined the effects of gender and work-groups' perceptions of climate for sexual harassment on the relationship between individuals' sexual harassment experiences and job-related outcomes (namely, job satisfaction, affective organizational commitment, work withdrawal, and job withdrawal). Drawing from a variety of theories, we proposed that a beneficial climate would buffer men from negative outcomes, but would intensify negative outcomes for women. Significant three-way interactions were found for job satisfaction, affective organizational commitment, and job withdrawal. Results indicated that beneficial work-group climate perceptions buffered men from decrements in job satisfaction and work withdrawal, but intensified decrements in all three outcomes for women. Implications for research and practice are discussed.
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Information is scarce on gray whale (Eschrichtius robustus) anatomy and that of mysticetes in general. Dissection of the head of a neonatal gray whale revealed novel anatomical details of the eye, blowhole, incisive papilla with a...
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Information is scarce on gray whale (Eschrichtius robustus) anatomy and that of mysticetes in general. Dissection of the head of a neonatal gray whale revealed novel anatomical details of the eye, blowhole, incisive papilla with associated nasopalatine ducts, sensory hairs, and throat grooves. Compared to a similar sized right whale calf, the gray whale eyeball is nearly twice as long. The nasal cartilages of the gray whale, located between the blowholes, differ from the bowhead in having accessory cartilages. A small, fleshy incisive papilla bordered by two blind nasopalatine pits near the palate's rostral tip, previously undescribed in gray whales, may be associated with the vomeronasal organ, although histological evidence is needed for definitive identification. Less well known among mysticetes are the numerous elongated, stiff sensory hairs (vibrissae) observed on the gray whale rostrum from the ventral tip to the blowhole and on the mandible. These hairs are concentrated on the chin, and those on the lower jaw are arranged in a V-shaped pattern. We confirm the presence of two primary, anteriorly converging throat grooves, confined to the throat region similar to those of ziphiid and physeteroid odontocetes. A third, shorter groove occurs lateral to the left primary groove. The throat grooves in the gray whale have been implicated in gular expansion during suction feeding. Anat Rec, 298: 648-659, 2015. (C) 2015 Wiley Periodicals, Inc.
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Our focus was to design harvestmen-specific PCR primers to target both introns and exons of the nuclear protein-coding gene Elongation Factor 4 alpha (EF-1 alpha). We tested this primer set on ten genera representing all primary l...
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Our focus was to design harvestmen-specific PCR primers to target both introns and exons of the nuclear protein-coding gene Elongation Factor 4 alpha (EF-1 alpha). We tested this primer set on ten genera representing all primary lineages of Opiliones, with sets of close phylogenetic relatives (i.e., sets of several congeners) included to specifically assess utility at shallow phylogenetic levels. Our research also included the collection of parallel mitochondrial protein-coding DNA sequence datasets for the congeneric sets to compare relative rates of evolution and gene tree congruence for EF-1 alpha versus mitochondrial data. The harvestmen primers resulted in successful amplification for nine of ten tested genera. Exon sequences for these nine genera appear orthologous to previously-reported EF-1 alpha Opiliones sequences, which were generated using RT-PCR methods. Newly-generated exon sequences are interrupted by three separate spliceosomal introns; two introns are restricted to one or two genera, but a third intron is conserved in position across all surveyed genera. Phylogenetic analyses of EF-1 alpha nucleotide data for congeneric sets result in gene trees that are generally congruent with mitochondrial gene trees, with EF-1 alpha phylogenetic signal coming from both intron and exon sites, and resolving apparently recent divergences (e.g., as recent as one million years ago). Overall, the combination of gene orthology, conserved intron position, and gene tree congruence at shallow levels suggest that this gene region will prove generally useful for both phylogeographic and species-level phylogenetic analyses in Opiliones, complementing already-documented utility at higher taxonomic levels.
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Many alcohol-induced health complications are directly attributable to the toxicity of alcohol or its metabolites, but another potential health impact of alcohol may be on the microbial communities of the human gut. Clear distinct...
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Many alcohol-induced health complications are directly attributable to the toxicity of alcohol or its metabolites, but another potential health impact of alcohol may be on the microbial communities of the human gut. Clear distinctions between healthy and diseased-state gut microbiota have been observed in subjects with metabolic diseases, and recent studies suggest that chronic alcoholism is linked to gut microbiome dysbiosis. Here, we investigated the effects of moderate levels of alcohol consumption on the gut microbiome in both rats and humans. The gut microbiota of rats voluntarily consuming a 20 percent ethanol solution, on alternate days, were compared with a non-exposed control group to identify differential taxonomic and functional profiles. Gut microbial diversity profiles were determined using culture-independent amplification, next-generation sequencing and bioinformatic analysis of bacterial 16S ribosomal RNA gene sequence libraries. Our results showed that, compared with controls, ethanol-consuming rats experienced a significant decline in the biodiversity of their gut microbiomes, a state generally associated with dysbiosis. We also observed significant shifts in the overall diversity of the gut microbial communities and a dramatic change in the relative abundance of particular microbes, such as the Lactobacilli. We also compared our results to human fecal microbiome data collected as part of the citizen science American Gut Project. In contrast to the rat data, human drinkers had significantly higher gut microbial biodiversity than non-drinkers. However, we also observed that microbes that differed among the human subjects displayed similar trends in the rat model, including bacteria implicated in metabolic disease.
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