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We illustrate the extraordinary potential of the (far-IR) Origins Survey Spectrometer (OSS) on board the Origins Space Telescope (OST) to address a variety of open issues on the co-evolution of galaxies and AGNs. We present predictions for blind surveys, each of 1000 h, with different mapped areas (a shallow survey covering an area of 10 deg2 and a deep survey of 1 deg2) and two different concepts of the OST/OSS: with a 5.9 m telescope (Concept 2, our reference configuration) and with a 9.1 m telescope (Concept 1, previous configuration). In 1 000 h, surveys with the reference concept will detect from ∼1.9×106 to ∼8.7×106 lines from ∼4.8×105 to 2.7×106 star-forming galaxies and from ∼1.4×104 to ∼3.8×104 lines from ∼1.3×104 to 3.5×104 AGNs. The shallow survey will detect substantially more sources than the deep one; the advantage of the latter in pushing detections to lower luminosities/higher redshifts turns out to be quite limited. The OST/OSS will reach, in the same observing time, line fluxes more than one order of magnitude fainter than the SPICA/SMI and will cover a much broader redshift range. In particular it will detect tens of thousands of galaxies at z ≥ 5, beyond the reach of that instrument. The polycyclic aromatic hydrocarbons lines are potentially bright enough to allow the detection of hundreds of thousands of star-forming galaxies up to z ∼ 8.5, i.e. all the way through the reionisation epoch. The proposed surveys will allow us to explore the galaxy–AGN co-evolution up to z ∼ 5.5−6 with very good statistics. OST Concept 1 does not offer significant advantages for the scientific goals presented here.
Strain rates are fundamental measures of ice flow and are used in a wide variety of glaciological applications including investigations of bed properties, calculations of basal mass balance on ice shelves, and constraints on ice rheological models. However, despite their extensive application, strain rates are calculated using a variety of methods and length scales and the details are often not specified. In this study, we compare the results of nominal and logarithmic strain-rate calculations based on a satellite-derived velocity field of the Antarctic ice sheet generated from Landsat 8 satellite data. Our comparison highlights the differences between the two common approaches in the glaciological literature. We evaluate the errors introduced by each approach and their impacts on the results. We also demonstrate the importance of choosing and specifying a length scale over which strain-rate calculations are made, which can strongly influence other derived quantities such as basal mass balance on ice shelves. Finally, we present strain-rate data products calculated using an approximate viscous length-scale with satellite observations of ice velocity for the Antarctic continent.
Previous work has shown that amygdala responsiveness to fearful expressions is inversely related to level of callous-unemotional (CU) traits (i.e. reduced guilt and empathy) in youth with conduct problems. However, some research has suggested that the relationship between pathophysiology and CU traits may be different in those youth with significant prior trauma exposure.
In experiment 1, 72 youth with varying levels of disruptive behavior and trauma exposure performed a gender discrimination task while viewing morphed fear expressions (0, 50, 100, 150 fear) and Blood Oxygenation Level Dependent responses were recorded. In experiment 2, 66 of these youth performed the Social Goals Task, which measures self-reports of the importance of specific social goals to the participant in provoking social situations.
In experiment 1, a significant CU traits-by-trauma exposure interaction was observed within right amygdala; fear intensity-modulated amygdala responses negatively predicted CU traits for those youth with low levels of trauma but positively predicted CU traits for those with high levels of trauma. In experiment 2, a bootstrapped model revealed that the indirect effect of fear intensity amygdala response on social goal importance through CU traits is moderated by prior trauma exposure.
This study, while exploratory, indicates that the pathophysiology associated with CU traits differs in youth as a function of prior trauma exposure. These data suggest that prior trauma exposure should be considered when evaluating potential interventions for youth with high CU traits.
Objective Chronic cerebrospinal venous insufficiency (CCSVI) has been hypothesized to be a risk factor for multiple sclerosis (MS). Venoplasty has been proposed as a treatment for CCSVI. The aim of our study was to gain a better understanding of the “real-world” safety and longitudinal effectiveness of venoplasty Methods: British Columbia residents who self-reported having had venoplasty and consented to participate in the study were interviewed and followed for up to 24 months post-therapy using standardized structured questionnaires Results: Participants reported procedure-related complications (11.5%) and complications within the first month after the procedure (17.3%). Initially, more than 40% of participants perceived that the venoplasty had had positive effects on their health conditions, such as fatigue, numbness, balance, concentration/memory and mobility. However, this improvement was not maintained over time Conclusions: Follow-up patient-reported outcomes indicated that the initial perception of the positive impact of venoplasty on the health conditions of MS patients was not sustained over time. In addition, venoplasty was not without associated morbidity.
The purpose of this communication is to explore the implications of genome editing techniques, such as CRISPR/Cas9, on public health–related responses to outbreaks of disease. The recent commercialization of genome editing techniques makes the creation and release of genetically altered pathogens a much easier task, increasing the possibility to the point of needing discussion. Three areas need to be addressed: predictions concerning potential genetic alterations, predictions and implications concerning the release of genetically altered pathogens, and the short- and long-term implications of the release of genetically altered pathogens. Full discourse on these topics among professionals in the area of public health will help to combat harm from the use of any genetically altered biologic weapons. The topics covered here include a review of the CRISPR/Cas9 gene editing technique, including a discussion of which possibilities utilize genome editing. We then address predictions about the application of gene alterations in the context of bioweapons. We discuss a few basic concepts about the evolution of an intentionally released genetically altered organism based on circumstances and patterns gleaned from observing nature in the hope that this will aid in the public health response to bioterrorism attack. (Disaster Med Public Health Preparedness. 2017;11:155–159)
The effect of diffusive shock acceleration on a distribution of particles is explored for multiple shocks, taking into account adiabatic expansion between the shocks. Specifically, the spectral index is calculated numerically for two cases: a sequence of identical shocks, and a sequence of pairs of shocks with alternating shock strength. How these two cases evolve to the asymptotic limit is examined, and it is shown that the evolution of the paired-shock case can be described by a sequence of identical shocks with shock strength equal to the mean of the two.
A simple model is presented for electron acceleration in extragalactic radio sources with two hot spots. The effect of diffusive shock acceleration by multiple shocks is calculated numerically, with adiabatic and synchrotron losses included. It is found for the sources 3C 20 and 3C 268·4 that a consistent set of model parameters exists which reproduce the observations. The model fails to reproduce the observations for the source 3C 196.
This article considers the hypothesis that the positive actions taken by members of Congress (MCs) influence citizens’ evaluations of them, their party, and Congress as an institution. We begin with a look at the available cross-sectional survey data on contact with legislators and legislator and institutional approval. Their legislative responsiveness appears to have a small spillover effect on institutions. However, when we employ a unique panel design that controls for prior levels of opinion and avoids recall bias, we find no evidence of spillover effects. Overall, we find that constituents who received a response from their own MC evaluate that representative more positively than those who did not receive a response, but legislator responsiveness does not predict evaluations of the MC’s political party or the Congress.
Impulsivity is a core feature of borderline personality disorder (BPD) and is most frequently measured using self-rating scales. There is a need to find objective, valid and reliable measures of impulsivity. This study aimed to examine performance of participants with BPD compared with healthy controls on delay and probabilistic discounting tasks and the stop-signal task (SST), which are objective measures of choice and motor impulsivity, respectively.
A total of 20 participants with BPD and 21 healthy control participants completed delay and probabilistic discounting tasks and the SST. They also completed the Barratt Impulsiveness Scale (BIS), a self-rating measure of impulsivity.
Participants with BPD showed significantly greater delay discounting than controls, manifest as a greater tendency to accept the immediately available lesser reward rather than waiting longer for a greater reward. Similarly they showed significantly greater discounting of rewards by the probability of payout, which correlated with past childhood trauma. Participants with BPD were found to choose the more certain and/or immediate rewards, irrespective of the value. On the SST the BPD and control groups did not differ significantly, demonstrating no difference in motor impulsivity. There was no significant difference between groups on self-reported impulsivity as measured by the BIS.
Measures of impulsivity show that while motor impulsivity was not significantly different in participants with BPD compared with controls, choice or reward-related impulsivity was significantly affected in those with BPD. This suggests that choice impulsivity but not motor impulsivity is a core feature of BPD.
Bacterial endospores are resistant to many environmental factors from temperature extremes to ultraviolet irradiation and are generally more difficult to inactivate or kill than vegetative bacterial cells. It is often considered necessary to treat spores or samples containing spores with chemical fixative solutions for prolonged periods of time (e.g., 1–21 days) to achieve fixation/inactivation to enable electron microscopy (EM) examination outside of containment laboratories. Prolonged exposure to chemical fixatives, however, can alter the ultrastructure of spores for EM analyses. This study was undertaken to determine the minimum amount of time required to inactivate/sterilize and fix spore preparations from several bacterial species using a universal fixative solution for EM that maintains the ultrastructural integrity of the spores. We show that a solution of 4% paraformaldehyde with 1% glutaraldehyde inactivated spore preparations of Bacillus anthracis, Bacillus cereus, Bacillus megaterium, Bacillus thuringiensis, and Clostridium perfringens in 30 min, and Bacillus subtilis in 240 min. These results suggest that this fixative solution can be used to inactivate and fix spores from several major groups of bacterial spore formers after 240 min, enabling the fixed preparations to be removed from biocontainment and safely analyzed by EM outside of biocontainment.
Completing the census of AGN in the Universe is the key to understanding the cosmic evolution of supermassive black holes (SMBH) and galaxies, and to resolving the spectrum of the X-ray background (XRB). However, a large population of AGN, especially the heavily obscured, Compton-thick AGN, are still missing from even the deepest X-ray surveys. The infrared spectra energy distribution (SED) of distant star-forming galaxies can reveal the presence of bright AGN activity. Using some of the deepest infrared, X-ray and radio data available in the GOODS fields, we identify a population of infrared bright quasars at redshift z ~ 2, which are often missed in the X-ray band. Amongst these sources the number of obscured and heavily-obscured quasars is much higher than those previously found in several X-ray and optical selected samples. A unique view on these heavily-obscured quasars is now given at high energies by NuSTAR. I will present the first NuSTAR detection of a heavily obscured quasar at z 2. This source is a potential archetype of the heavily-obscured high-z AGN in which most of the black hole growth is happening, that can explain the mysterious missing fraction of the XRB.
Although several lichen inventories exist for European ultramafic sites, only four surveys of serpentine lichens for North America have been published to date. Of those, only one has been conducted in California. We conducted a survey of saxicolous lichens from ultramafic rocks (including nephrite, partially serpentinized peridotite, and serpentinite) and non-ultramafic rocks (including silica-carbonate, shale, and sandstone) at the New Idria serpentinite mass, San Benito County, California. X-ray Fluorescence Analysis of the rocks from which the lichens were collected revealed significant elemental differences between the ultramafic and non-ultramafic rocks for 26 of the 32 major and trace elements analyzed. We identified a total of 119 species of lichenized and lichenicolous fungi; 60 species were restricted to ultramafic substrata, 19 to silica-carbonate, and 15 to shale and sandstone. Only 4 species were shared in common. A permutational multivariate analysis of variance (perMANOVA) test revealed significant differences in lichen assemblages between ultramafic and non-ultramafic rocks at the species level but not at the generic level, with species richness (alpha-diversity) significantly greater at the ultramafic sites. We suggest that, although differences in geochemistry clearly influence the lichen community composition, other factors, especially substratum age and the physical characteristics of the rock, are of equal, if not greater, importance. Of all the species collected, six, Buellia aethalea, B. ocellata, Caloplaca oblongula, Rhizocarpon saurinum, Thelocarpon laureri, and Trapelia obtegens, are reported new to California, along with an apparently previously undescribed Solenopsora sp. The rest of the species encountered are relatively frequent in the lichen flora of southern and central California, except Aspicilia praecrenata, a rare California endemic that we collected on both ultramafic and non-ultramafic rocks.