26 research outputs found

    A New Era in Extragalactic Background Light Measurements: The Cosmic History of Accretion, Nucleosynthesis and Reionization

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    (Brief Summary) What is the total radiative content of the Universe since the epoch of recombination? The extragalactic background light (EBL) spectrum captures the redshifted energy released from the first stellar objects, protogalaxies, and galaxies throughout cosmic history. Yet, we have not determined the brightness of the extragalactic sky from UV/optical to far-infrared wavelengths with sufficient accuracy to establish the radiative content of the Universe to better than an order of magnitude. Among many science topics, an accurate measurement of the EBL spectrum from optical to far-IR wavelengths, will address: What is the total energy released by stellar nucleosynthesis over cosmic history? Was significant energy released by non-stellar processes? Is there a diffuse component to the EBL anywhere from optical to sub-millimeter? When did first stars appear and how luminous was the reionization epoch? Absolute optical to mid-IR EBL spectrum to an astrophysically interesting accuracy can be established by wide field imagingat a distance of 5 AU or above the ecliptic plane where the zodiacal foreground is reduced by more than two orders of magnitude.Comment: 7 pages; Science White Paper for the US Astro 2010-2020 Decadal Survey. If interested in further community-wide efforts on this topic please contact the first autho

    Variation in the Large-Scale Organization of Gene Expression Levels in the Hippocampus Relates to Stable Epigenetic Variability in Behavior

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    Despite sharing the same genes, identical twins demonstrate substantial variability in behavioral traits and in their risk for disease. Epigenetic factors-DNA and chromatin modifications that affect levels of gene expression without affecting the DNA sequence-are thought to be important in establishing this variability. Epigenetically-mediated differences in the levels of gene expression that are associated with individual variability traditionally are thought to occur only in a gene-specific manner. We challenge this idea by exploring the large-scale organizational patterns of gene expression in an epigenetic model of behavioral variability.To study the effects of epigenetic influences on behavioral variability, we examine gene expression in genetically identical mice. Using a novel approach to microarray analysis, we show that variability in the large-scale organization of gene expression levels, rather than differences in the expression levels of specific genes, is associated with individual differences in behavior. Specifically, increased activity in the open field is associated with increased variance of log-transformed measures of gene expression in the hippocampus, a brain region involved in open field activity. Early life experience that increases adult activity in the open field also similarly modifies the variance of gene expression levels. The same association of the variance of gene expression levels with behavioral variability is found with levels of gene expression in the hippocampus of genetically heterogeneous outbred populations of mice, suggesting that variation in the large-scale organization of gene expression levels may also be relevant to phenotypic differences in outbred populations such as humans. We find that the increased variance in gene expression levels is attributable to an increasing separation of several large, log-normally distributed families of gene expression levels. We also show that the presence of these multiple log-normal distributions of gene expression levels is a universal characteristic of gene expression in eurkaryotes. We use data from the MicroArray Quality Control Project (MAQC) to demonstrate that our method is robust and that it reliably detects biological differences in the large-scale organization of gene expression levels.Our results contrast with the traditional belief that epigenetic effects on gene expression occur only at the level of specific genes and suggest instead that the large-scale organization of gene expression levels provides important insights into the relationship of gene expression with behavioral variability. Understanding the epigenetic, genetic, and environmental factors that regulate the large-scale organization of gene expression levels, and how changes in this large-scale organization influences brain development and behavior will be a major future challenge in the field of behavioral genomics

    Development and validation of the multi-dimensional questionnaire of scientifically unsubstantiated beliefs

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    Objective: There are several existing questionnaires measuring paranormal or scientifically unsubstantiated beliefs but none cover a broad spectrum of cognitions while also being up-to-date and unconstrained by theoretical limitations. There is also a debate about the number of separate types of belief. Thereby, reported here is the development and validation of a new multidimensional questionnaire measure of scientifically unsubstantiated beliefs in the general UK population. Method & Results. In Study 1, participants (N=393) completed a questionnaire containing a pool of 82 items covering nine facets of belief discernible conceptually within the existing research literature. Scree analysis followed by exploratory factor analysis indicated the existence of four empirically observable factors: belief in supernatural forces; belief in God and destiny; belief in alien visitation, monsters and conspiracies; and belief in consciousness beyond the body. Twenty-four items were selected as measures of these factors. Studies 2, 3 and 4 demonstrated the convergent and divergent validity of the four empirically-derived questionnaire subscales and their internal reliability. Conclusion. The resultant new Multi-dimensional Questionnaire of Scientifically Unsubstantiated Beliefs (MQSUB) is a psychometrically robust measure and comprises a comprehensive framework which can be used to systematically investigate the psychological and social concomitants of such beliefs

    Recent partner violence and sexual and drug-related STI/HIV risk among adolescent and young adult women attending family planning clinics

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    Background/objectivesAdolescent and young adult women are at high risk for sexually transmitted infections (STIs)/HIV and intimate partner violence (IPV). We evaluate the prevalence of IPV in the past 3 months and its associations with STI/HIV risk, STI and related care-seeking over the same time period.MethodsFemale family planning clinic patients ages 16-29 years (n=3504) participated in a cross-sectional survey in 2011-2012 as a baseline assessment for an intervention study. We examined associations of recent IPV with sexual and drug-related STI/HIV risk behaviour, self-reported STI and STI-related clinical care seeking via logistic regression.ResultsRecent physical or sexual IPV (prevalence 11%) was associated with recent sexual and drug-related STI/HIV risk, specifically unprotected vaginal sex (adjusted OR (AOR) 1.93, 95% CI 1.52 to 2.44), unprotected anal sex (AOR 2.22, 95% CI 1.51 to 3.27) and injection drug use, their own (AOR 3.39, 95% CI 1.47 to 7.79) and their partner's (AOR 3.85, 1.91 to 7.75). IPV was also linked with coercive sexual risk: involuntary condom non-use (AOR 1.87 to 95% CI 1.51 to 2.33), and fears of requesting condoms (AOR 4.15, 95% CI 2.73 to 6.30) and refusing sex (AOR 11.84, 95% CI 7.59 to 18.45). STI-related care-seeking was also more common among those abused (AOR 2.49, 95% CI 1.87 to 3.31).ConclusionsRecent IPV is concurrent with sexual and drug-related STI/HIV risk, including coercive sexual risk, thus compromising women's agency in STI/HIV risk reduction. Clinical risk assessments should broaden to include unprotected heterosexual anal sex, coercive sexual risk and IPV, and should promote safety and harm reduction

    Intra-Amniotic Infection with Ureaplasma parvum Causes Preterm Birth and Neonatal Mortality That Are Prevented by Treatment with Clarithromycin

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    Preterm birth is the leading cause of neonatal morbidity and mortality worldwide. Multiple etiologies are associated with preterm birth; however, 25% of preterm infants are born to a mother with intra-amniotic infection, most commonly due to invasion of the amniotic cavity by Ureaplasma species. Much research has focused on establishing a link between Ureaplasma species and adverse pregnancy/neonatal outcomes; however, little is known about the taxonomy of and host response against Ureaplasma species. Here, we applied a multifaceted approach, including human samples, in vivo models, and in vitro manipulations, to study the maternal-fetal immunobiology of Ureaplasma infection during pregnancy. Furthermore, we investigated the use of clarithromycin as a treatment for this infection. Our research provides translational knowledge that bolsters scientific understanding of Ureaplasma species as a cause of adverse pregnancy/neonatal outcomes and gives strong evidence for the use of clarithromycin as the recommended treatment for women intra-amniotically infected with Ureaplasma species.Intra-amniotic infection is strongly associated with adverse pregnancy and neonatal outcomes. Most intra-amniotic infections are due to Ureaplasma species; however, the pathogenic potency of these genital mycoplasmas to induce preterm birth is still controversial. Here, we first laid out a taxonomic characterization of Ureaplasma isolates from women with intra-amniotic infection, which revealed that Ureaplasma parvum is the most common bacterium found in this clinical condition. Next, using animal models, we provided a causal link between intra-amniotic inoculation with Ureaplasma species and preterm birth. Importantly, the intra-amniotic inoculation of Ureaplasma species induced high rates of mortality in both preterm and term neonates. The in vivo potency of U. parvum to induce preterm birth was not associated with known virulence factors. However, term-derived and preterm-derived U. parvum isolates were capable of inducing an intra-amniotic inflammatory response. Both U. parvum isolates invaded several fetal tissues, primarily the fetal lung, and caused fetal inflammatory response syndrome. This bacterium was also detected in the placenta, reproductive tissues, and most severely in the fetal membranes, inducing a local inflammatory response that was replicated in an in vitro model. Importantly, treatment with clarithromycin, a recently recommended yet not widely utilized antibiotic, prevented the adverse pregnancy and neonatal outcomes induced by U. parvum. These findings shed light on the maternal-fetal immunobiology of intra-amniotic infection
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