CHANDRA Observations of X-ray Jet Structure on kpc to Mpc Scales

With its exquisite spatial resolution of better than 0.5 arcsecond, the Chandra observatory is uniquely capable of resolving and studying the spatial structure of extragalactic X-ray jets on scales of a few to a few hundred kilo-parsec. Our analyses of four recent Chandra images of quasar jets interpret the X-ray emission as inverse Compton scattering of high energy electrons on the cosmic microwave background. We infer that these jets are in bulk relativistic motion, carrying kinetic powers upwards of 10^46 ergs/s to distances of hundreds of kpc, with very high efficiency.Comment: 4 pages, 3 figures, to be published in the proceedings of the Bologna jet workshop, "The Physics of Relativistic Jets in the CHANDRA and XMM Era.

Maternal occupation in agriculture and risk of limb defects in Washington State, 1980-1993

Objectives. This study examined the association between maternal occupational exposure to agricultural chemicals and the risk of limb defects among offspring. Methods. A retrospective cohort study was conducted using Washington State birth records for the years 1980 through 1993. The exposed group, consisting of 4466 births to mothers employed in agriculture, was compared with 2 reference groups: (i) 23 512 births in which neither parent worked in agriculture (″nonagricultural″ group) and (ii) 5994 births in which only the father worked in agriculture (″paternal agriculture″ group). The outcome of interest was limb defects [syndactyly, polydactyly, adactyly, and ″other limb reductions″ (as listed in the birth record)]. Results. An elevated risk of limb defects was observed for the exposed group in comparison with both the nonagricultural and paternal agriculture groups, with ethnicity-adjusted prevalence ratios of 2.6 [95% confidence interval (95% CI) 1.1-5.8] and 2.6 (95% CI 0.7-9.5), respectively. Conclusions. These results support the hypothesis that maternal occupational exposure to agricultural chemicals may increase the risk of giving birth to a child with limb defects

Partial characterization of Ia antigens from murine lymphoid cells

Congenic anti-Ia antisera were used to bind radiolabelled Ia antigens from cells of various strains of mice of known H-2 haplotype. The results indicate that Ia antigens are proteins of molecular weight 30,000 to 35,000 daltons. The Ia antigens are distinct from known H-2 antigens as judged by independent immunoprecipitation as well as by molecular weight. Ia antigens are synthesized by, and are present on the surface of lymphoid cells as evidenced by incorporation studies using 3 H-leucine and enzymatic radioiodination of cells, respectively. Tissue distribution of cell surface Ia suggests that Ia antigens are on B cells. Ia antigens were detected in the incubation media of 3 H-leucine labeled splenocytes suggesting that antigens may be secreted.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46728/1/251_2005_Article_BF01564048.pd

A Multi-band Study of the Remarkable Jet in Quasar 4C+19.44

We present arcsecond-resolution data in the radio, IR, optical, and X-ray for 4C+19.44 (=PKS 1354+195), the longest and straightest quasar jet with deep X-ray observations. We report results from radio images with half to one arcsecond angular resolution at three frequencies, plus Hubble Space Telescope and Spitzer data. The Chandra data allow us to measure the X-ray spectral index in 10 distinct regions along the 18'' jet and compare with the radio index. The radio and X-ray spectral indices of the jet regions are consistent with a value of $\alpha =0.80$ throughout the jet, to within $2\sigma$ uncertainties. The X-ray jet structure to the south extends beyond the prominent radio jet and connects to the southern radio lobe, and there is extended X-ray emission, both in the direction of the unseen counter-jet, and also coincident with the northern radio lobe. This jet is remarkable because its straight appearance over a large distance allows the geometry factors to be taken as fixed along the jet. Using the model of inverse Compton scattering of the cosmic microwave background (iC/CMB) by relativistic electrons, we find that the magnetic field strengths and Doppler factors are relatively constant along the jet. If instead the X-rays are synchrotron emission, they must arise from a population of electrons distinct from the particles producing the radio synchrotron spectrum

Physics of Solar Prominences: I - Spectral Diagnostics and Non-LTE Modelling

This review paper outlines background information and covers recent advances made via the analysis of spectra and images of prominence plasma and the increased sophistication of non-LTE (ie when there is a departure from Local Thermodynamic Equilibrium) radiative transfer models. We first describe the spectral inversion techniques that have been used to infer the plasma parameters important for the general properties of the prominence plasma in both its cool core and the hotter prominence-corona transition region. We also review studies devoted to the observation of bulk motions of the prominence plasma and to the determination of prominence mass. However, a simple inversion of spectroscopic data usually fails when the lines become optically thick at certain wavelengths. Therefore, complex non-LTE models become necessary. We thus present the basics of non-LTE radiative transfer theory and the associated multi-level radiative transfer problems. The main results of one- and two-dimensional models of the prominences and their fine-structures are presented. We then discuss the energy balance in various prominence models. Finally, we outline the outstanding observational and theoretical questions, and the directions for future progress in our understanding of solar prominences.Comment: 96 pages, 37 figures, Space Science Reviews. Some figures may have a better resolution in the published version. New version reflects minor changes brought after proof editin

Optimism is not associated with two indicators of DNA methylation aging

Evidence indicates associations between higher optimism and reduced risk of age-related conditions and premature mortality. This suggests optimism is a positive health asset, but research identifying potential biological mechanisms underlying these associations remains limited. One potential pathway is slower cellular aging, which may delay age-related deterioration in health. Data were from the Women's Health Initiative (WHI) (N=3,298) and the Veterans Affairs Normative Aging Study (NAS) (N=514), and included dispositional and explanatory style optimism measures. We evaluated whether higher optimism was associated with metrics suggestive of less cellular aging, as indicated by two DNA methylation algorithms, intrinsic (IEAA) and extrinsic epigenetic age acceleration (EEAA); these algorithms represent accelerated biologic aging that exceeds chronological age. We used linear regression models to test our hypothesis while considering several covariates (sociodemographics, depressive symptoms, health behaviors). In both cohorts, we found consistently null associations of all measures of optimism with both measures of DNA methylation aging, regardless of covariates considered. For example, in fully-adjusted models, dispositional optimism was not associated with either IEAA (WHI:β=0.02; 95% Confidence Interval [CI]:-0.15-0.20; NAS:β=-0.06; 95% CI:-0.56-0.44) or EEAA (WHI:β=-0.04; 95% CI: -0.26-0.17; NAS:β=-0.17; 95% CI: -0.80-0.46). Higher optimism was not associated with reduced cellular aging as measured in this study

Epigenome-Wide Analysis of DNA Methylation and Optimism in Women and Men

Objective: Higher optimism is associated with reduced mortality and a lower risk of age-related chronic diseases. DNA methylation (DNAm) may provide insight into mechanisms underlying these relationships. We hypothesized that DNAm would differ among older individuals who are more versus less optimistic. Methods: Using cross-sectional data from two population-based cohorts of women with diverse races/ethnicities (n = 3816) and men (only White, n = 667), we investigated the associations of optimism with epigenome-wide leukocyte DNAm. Random-effects meta-analyses were subsequently used to pool the individual results. Significantly differentially methylated cytosine-phosphate-guanines (CpGs) were identified by the “number of independent degrees of freedom” approach: effective degrees of freedom correction using the number of principal components (PCs), explaining >95% of the variation of the DNAm data (PC-correction). We performed regional analyses using comb-p and pathway analyses using the Ingenuity Pathway Analysis software. Results: We found that essentially all CpGs (total probe N = 359,862) were homogeneous across sex and race/ethnicity in the DNAm-optimism association. In the single CpG site analyses based on homogeneous CpGs, we identified 13 significantly differentially methylated probes using PC-correction. We found four significantly differentially methylated regions and two significantly differentially methylated pathways. The annotated genes from the single CpG site and regional analyses are involved in psychiatric disorders, cardiovascular disease, cognitive impairment, and cancer. Identified pathways were related to cancer, and neurodevelopmental and neurodegenerative disorders. Conclusion: Our findings provide new insights into possible mechanisms underlying optimism and health

Comedy in Unfunny Times: News Parody and Carnival after 9/11

Comedy has a special role in helping societies manage crisis moments, and the U.S. media paid considerable attention to the proper role of comedy in public culture after the 9/11 tragedies. As has been well documented, many popular U.S. comic voices were paralyzed in trying to respond to 9/11 or disciplined by audiences when they did. Starting with these obstacles in mind, this essay analyzes early comic responses to 9/11, and particularly those of the print and online news parody The Onion, as an example of how “fake” news discourse could surmount the rhetorical chill that fell over public culture after the tragedies. By exposing the news as “mere” production and by setting an agenda for learning about Islamic culture and Middle East politics, The Onion avoided violating decorum and invited citizen participation. This kind of meta-discourse was crucial after 9/11, when shifting rules for decorum created controversy and as official voices in government and media honed frames and narratives for talking about the attacks

A comprehensive SARS-CoV-2 and COVID-19 review, Part 2: host extracellular to systemic effects of SARS-CoV-2 infection

COVID-19, the disease caused by SARS-CoV-2, has caused significant morbidity and mortality worldwide. The betacoronavirus continues to evolve with global health implications as we race to learn more to curb its transmission, evolution, and sequelae. The focus of this review, the second of a three-part series, is on the biological effects of the SARS-CoV-2 virus on post-acute disease in the context of tissue and organ adaptations and damage. We highlight the current knowledge and describe how virological, animal, and clinical studies have shed light on the mechanisms driving the varied clinical diagnoses and observations of COVID-19 patients. Moreover, we describe how investigations into SARS-CoV-2 effects have informed the understanding of viral pathogenesis and provide innovative pathways for future research on the mechanisms of viral diseases