The Pain Divide: a cross-sectional analysis of chronic pain prevalence, pain intensity and opioid utilisation in England

Objectives: Our central research question was, in England, are geographical inequalities in opioid use driven by health need (pain)? To answer this question, our study examined: (1) if there are regional inequalities in rates of chronic pain prevalence, pain intensity and opioid utilisation in England; (2) if opioid use and chronic pain are associated after adjusting for individual-level and area-level confounders. Design: Cross-sectional study design using data from the Health Survey for England 2011. Setting England. Primary and secondary outcome measures: Chronic pain prevalence, pain intensity and opioid utilisation. Participants: Participant data relating to chronic pain prevalence, pain intensity and opioid usage data were obtained at local authority level from the Health Survey for England 2011; in total, 5711 respondents were included in our analysis. Methods: Regional and local authority data were mapped, and a generalised linear model was then used to explore the relationships between the data. The model was adjusted to account for area-level and individual-level variables. Results: There were geographical variations in chronic pain prevalence, pain intensity and opioid utilisation across the English regions—with evidence of a ‘pain divide’ between the North and the South, whereby people in the North of England more likely to have ‘severely limiting’ or ‘moderately limiting’ chronic pain. The intensity of chronic pain was significantly and positively associated with the use of opioid analgesics. Conclusions: There are geographical differences in chronic pain prevalence, pain intensity and opioid utilisation across England—with evidence of a ‘pain divide’. Given the public health concerns associated with the long-term use of opioid analgesics—and their questionable activity in the management of chronic pain—more guidance is needed to support prescribers in the management of chronic pain, so the initiation of opioids can be avoided

Bezlotoxumab for prevention of recurrent Clostridium difficile infection in patients at increased risk for recurrence

Background: Bezlotoxumab is a human monoclonal antibody against Clostridium difficile toxin B indicated to prevent C. difficile infection (CDI) recurrence (rCDI) in adults at high risk for rCDI. This post hoc analysis of pooled monocolonal antibodies for C.difficile therapy (MODIFY) I/II data assessed bezlotoxumab efficacy in participants with characteristics associated with increased risk for rCDI. Methods: The analysis population was the modified intent-to-treat population who received bezlotoxumab or placebo (n = 1554) by risk factors for rCDI that were prespecified in the statistical analysis plan: age ≥65 years, history of CDI, compromised immunity, severe CDI, and ribotype 027/078/244. The proportion of participants with rCDI in 12 weeks, fecal microbiota transplant procedures, 30-day all cause and CDI-associated hospital readmissions, and mortality at 30 and 90 days after randomization were presented. Results: The majority of enrolled participants (75.6%) had ≥1 risk factor; these participants were older and a higher proportion had comorbidities compared with participants with no risk factors. The proportion of placebo participants who experienced rCDI exceeded 30% for each risk factor compared with 20.9% among those without a risk factor, and the rCDI rate increased with the number of risk factors (1 risk factor: 31.3%; ≥3 risk factors: 46.1%). Bezlotoxumab reduced rCDI, fecal microbiota transplants, and CDI-associated 30-day readmissions in participants with risk factors for rCDI. Conclusions: The risk factors prespecified in the MODIFY statistical analysis plan are appropriate to identify patients at high risk for rCDI. While participants with ≥3 risk factors had the greatest reduction of rCDI with bezlotoxumab, those with 1 or 2 risk factors may also benefit. Clinical Trials Registration: NCT01241552 (MODIFY I) and NCT01513239 (MODIFY II)

An Imaging and Spectroscopic Study of the z=3.38639 Damped Lyman Alpha System in Q0201+1120: Clues to Star Formation Rate at High Redshift

We present the results of a series of imaging and spectroscopic observations aimed at identifying and studying the galaxy responsible for the z = 3.38639 damped lya system in the z = 3.61 QSO Q0201+1120. We find that the DLA is part of a concentration of matter which includes at least four galaxies (probably many more) over linear comoving dimensions, greater than 5h^-1Mpc. The absorber may be a 0.7 L* galaxy at an impact parameter of 15 h^-1 kpc, but follow-up spectroscopy is still required for positive identification. The gas is turbulent, with many absorption components distributed over approximately 270 km/s and a large spin temperature, T_s greater than 4000K. The metallicity is relatively high for this redshift, Z(DLA) approximately 1/20 Z(solar). From consideration of the relative ratios of elements which have different nucleosynthetic timescales, it would appear that the last major episode of star formation in this DLA occurred at z greater than 4.3, more than approximately 500 Myr prior to the time when we observe it.Comment: Accepted for publication in Ap

Dust-driven Dynamos in Accretion Disks

Magnetically driven astrophysical jets are related to accretion and involve toroidal magnetic field pressure inflating poloidal magnetic field flux surfaces. Examination of particle motion in combined gravitational and magnetic fields shows that these astrophysical jet toroidal and poloidal magnetic fields can be powered by the gravitational energy liberated by accreting dust grains that have become positively charged by emitting photo-electrons. Because a dust grain experiences magnetic forces after becoming charged, but not before, charging can cause irreversible trapping of the grain so dust accretion is a consequence of charging. Furthermore, charging causes canonical angular momentum to replace mechanical angular momentum as the relevant constant of the motion. The resulting effective potential has three distinct classes of accreting particles distinguished by canonical angular momentum, namely (i) "cyclotron-orbit", (ii) "Speiser-orbit", and (iii) "zero canonical angular momentum" particles. Electrons and ions are of class (i) but depending on mass and initial orbit inclination, dust grains can be of any class. Light-weight dust grains develop class (i) orbits such that the grains are confined to nested poloidal flux surfaces, whereas grains with a critical weight such that they experience comparable gravitational and magnetic forces can develop class (ii) or class (iii) orbits, respectively producing poloidal and toroidal field dynamos.Comment: 70 pages, 16 figure

Stereoscopic electron spectroscopy of solar hard X-ray flares with a single spacecraft

Hard X-ray (HXR) spectroscopy is the most direct method of diagnosing energetic electrons in solar flares. Here we present a technique which allows us to use a single HXR spectrum to determine an effectively stereoscopic electron energy distribution. Considering the Sun's surface to act as a 'Compton mirror' allows us to look at emitting electrons also from behind the source, providing vital information on downward-propagating particles. Using this technique we determine simultaneously the electron spectra of downward and upward directed electrons for two solar flares observed by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). The results reveal surprisingly near-isotropic electron distributions, which contrast strongly with the expectations from the standard model which invokes strong downward beaming, including collisional thick-target model.Comment: 7 pages, 3 figures, accepted to Astrophysical Journal Letter

Obscured AGNS in Bulgeless Hosts Discovered By Wise : The Case Study of Sdss J1224+5555

There is mounting evidence that supermassive black holes form and grow in bulgeless galaxies. However, a robust determination of the fraction of AGNs in bulgeless galaxies, an important constraint to models of supermassive black hole seed formation and merger-free models of AGN fueling, is unknown, since optical studies have been shown to be incomplete for low mass AGNs. In a recent study using the Wide-field Infrared Survey Explorer, we discovered hundreds of bulgeless galaxies that display mid-infrared signatures of extremely hot dust suggestive of powerful accreting massive black holes, despite having no signatures of black hole activity at optical wavelengths. Here we report X-ray follow-up observations of J122434.66+555522.3, a nearby (z=0.052) isolated bulgeless galaxy that contains an unresolved X-ray source detected at the 3 sigma level by XMM-Newton with an observed luminosity uncorrected for intrinsic absorption of L2-10~keV=1.1+/-0.4 1040 ergs s-1. Ground-based near-infrared spectroscopy with the Large Binocular Telescope together with multiwavelength observations from ultraviolet to millimeter wavelengths together suggest that J1224+5555 harbors a highly absorbed AGN with an intrinsic absorption of ~NH \u3e1024 cm-2. The hard X-ray luminosity of the putative AGN corrected for absorption is L2-10~keV~3x1042 ergs s-1, which, depending on the bolometric correction factor, corresponds to a bolometric luminosity of the AGN of 6x1043 ergs s-1 - 3x1044 erg s-1, and a lower mass limit for the black hole of MBH~2x106 Msun, based on the Eddington limit. While enhanced X-ray emission and hot dust can be produced by star formation in extremely low metallicity environments typical in dwarf galaxies, J1224+5555 has a stellar mass of ~2.0 x 1010 Msun and an above solar metallicity (12 + logO/H = 9.11), typical of our WISE-selected bulgeless galaxy sample. While collectively these observations suggest the presence of an AGN, we caution that identifying obscured AGNs in the low-luminosity regime is challenging and often requires multiwavelength observations. These observations suggest that low-luminosity AGNs can be heavily obscured and reside in optically quiescent galaxies, adding to the growing body of evidence that the fraction of bulgeless galaxies with accreting black holes may be significantly underestimated based on optical studies

HST Observations of SGR 0526-66: New Constraints on Accretion and Magnetar Models

Soft Gamma-ray Repeaters (SGRs) are among the most enigmatic sources known today. Exhibiting huge X- and Gamma-ray bursts and flares, as well as soft quiescent X-ray emission, their energy source remains a mystery. Just as mysterious are the Anomalous X-ray pulsars (AXPs), which share many of the same characteristics. Thanks to recent Chandra observations, SGR 0526-66, the first SGR, now appears to be a transition object bridging the two classes, and therefore observations of it have implications for both SGRs and AXPs. The two most popular current models for their persistent emission are accretion of a fossil disk or decay of an enormous (~10^15 G) magnetic field in a magnetar. We show how deep optical observations of SGR 0526-66, the only SGR with small enough optical extinction for meaningful observations, show no evidence of an optical counterpart. These observation place strong new constraints on both accretion disk and magnetar models, and suggest that the spectral energy distribution may peak in the hard-UV. Almost all accretion disks are excluded by the optical data, and a magnetar would require a ~10^15-10^16 G field.Comment: 23 pages, 5 figures. Accepted by Ap

Fast Camera Imaging of Hall Thruster Ignition

Hall thrusters provide efficient space propulsion by electrostatic acceleration of ions. Rotating electron clouds in the thruster overcome the space charge limitations of other methods. Images of the thruster startup, taken with a fast camera, reveal a bright ionization period which settles into steady state operation over 50 μs. The cathode introduces azimuthal asymmetry, which persists for about 30 μs into the ignition. Plasma thrusters are used on satellites for repositioning, orbit correction and drag compensation. The advantage of plasma thrusters over conventional chemical thrusters is that the exhaust energies are not limited by chemical energy to about an electron volt. For xenon Hall thrusters, the ion exhaust velocity can be 15-20 km/s, compared to 5 km/s for a typical chemical thruste

Search for cold gas in z>2 damped Lyman-alpha systems: 21-cm and H_2 absorption

(Abridged) We present the results of a systematic GBT and GMRT survey for 21-cm absorption in a sample of 10 DLAs at 2<z_abs<3.4. Analysis of L-band VLBA images of the background QSOs are also presented. We detect 21-cm absorption in only one DLA (at z_abs = 3.1745 towards J1337+3152). Combining our data with the data from the literature (a sample of 28 DLAs) and assuming the measured core fraction at milliarcsecond scale to represent the gas covering factor, we find that the HI gas in DLAs at z> 2 is predominantly constituted by WNM. The detection rate of 21-cm absorption seems to be higher for systems with higher N(HI) or metallicity. However, no clear correlation is found between the integrated 21-cm optical depth (or spin temperature) and either N(HI), metallicity or velocity spread of the low ionization species. There are 13 DLAs in our sample for which high resolution optical spectra covering the expected wavelength range of H_2 absorption are available. We report the detection of H_2 molecules in the z_abs = 3.3871 21-cm absorber towards J0203+1134 (PKS 0201+113). In 8 cases, neither H_2 nor 21-cm absorption are detected. The lack of 21-cm and H_2 absorption in these systems can be explained if most of the HI in these DLAs originate from low density high temperature gas. In one case we have a DLA with 21-cm absorption not showing H_2 absorption. In two cases, both species are detected but do not originate from the same velocity component. In the remaining 2 cases 21-cm absorption is not detected despite the presence of H_2 with evidence for the presence of cold gas. All this is consistent with the idea that the H_2 components seen in DLAs are compact (with sizes of < 15 pc) and contain only a small fraction (i.e typically <10%) of the total N(HI) measured in the DLAs.Comment: Accepted for publication in MNRA