ABSTRACT We report on new spectral modeling of the accreting X-ray pulsar Hercules X-1. Our radiation-dominated radiative shock model is an implementation of the analytic work of Becker & Wolff on ...Comptonized accretion flows onto magnetic neutron stars. We obtain a good fit to the spin-phase-averaged 4-78 keV X-ray spectrum observed by the Nuclear Spectroscopic Telescope Array during a main-on phase of the Her X-1 35 day accretion disk precession period. This model allows us to estimate the accretion rate, the Comptonizing temperature of the radiating plasma, the radius of the magnetic polar cap, and the average scattering opacity parameters in the accretion column. This is in contrast to previous phenomenological models that characterized the shape of the X-ray spectrum, but could not determine the physical parameters of the accretion flow. We describe the spectral fitting details and discuss the interpretation of the accretion flow physical parameters.
We analyzed multiwavelength observations of the previously identified Galactic center X-ray binary CXO 174528.79-290942.8 (XID 6592) and determine that the near-infrared counterpart is a red ...supergiant based on its spectrum and luminosity. Scutum X-1 is the only previously known X-ray binary with a red supergiant donor star and closely resembles XID 6592 in terms of X-ray luminosity (LX), absolute magnitude, and IR variability (LIR,var), supporting the conclusion that XID 6592 contains a red supergiant donor star. The XID 6592 infrared counterpart shows variability of ∼0.5 mag in the Wide-field Infrared Survey Explorer-1 band (3.4 m) on timescales of a few hours. Other infrared data sets also show large-amplitude variability from this source at earlier epochs but do not show significant variability in recent data. We do not expect red supergiants to vary by ∼50% in luminosity over these short timescales, indicating that the variability should be powered by the compact object. However, the X-ray luminosity of this system is typically ∼1000× less than the variable luminosity in the infrared and falls below the Chandra detection limit. While X-ray reprocessing can produce large-amplitude fast infrared variability, it typically requires LIR,var to do so, indicating that another process must be at work. We suggest that this system may be a supergiant fast X-ray transient (SFXT), and that a large (∼1038 ergs s−1), fast (102-4 s) X-ray flare could explain the rapid IR variability and lack of a long-lasting X-ray outburst detection. SFXTs are normally associated with blue supergiant companions, so if confirmed, XID 6592 would be the first red supergiant SFXT, as well as the second X-ray red supergiant binary.
We report on the timing and spectral analysis of two Suzaku observations with different flux levels of the high-mass X-ray binary KS 1947+300 during its 2013 outburst. In agreement with simultaneous ...NuSTAR observations, the continuum is well described by an absorbed power law with a cutoff and an additional blackbody component. In addition, we find fluorescent emission from neutral, He-like, and even H-like iron. We determine a pulse period of ~18.8 s with the source showing a spin-up between the two observations. Both Suzaku observations show very similar behavior of the pulse profile, which is strongly energy dependent. This profile has an evolution from a profile with one peak at low energies to a profile with two peaks of different widths toward higher energies seen in both the Suzaku and NuSTAR data. Such an evolution to a more complex profile at higher energies is rarely seen in X-ray pulsars, most cases show the opposite behavior. Pulse phase-resolved spectral analysis shows a variation in the absorbing column density, NH, over pulse phase. Spectra taken during the pulse profile minima are intrinsically softer compared to the pulse phase-averaged spectrum.
IMPORTANCE Since 2009, quick-service restaurant chains, or fast-food companies, have agreed to depict healthy foods in their advertising targeted at children. OBJECTIVE To determine how children ...interpreted depictions of milk and apples in television advertisements for children’s meals by McDonald’s and Burger King (BK) restaurants. DESIGN, SETTING, AND PARTICIPANTS Descriptive qualitative study in a rural pediatric practice setting in Northern New England. A convenience sample of 99 children (age range, 3-7 years) was shown depictions of healthy foods in fast-food advertisements that aired from July 1, 2010, through June 30, 2011. The images from McDonald’s and BK showed milk and apples. Children were asked what they saw and not prompted to respond specifically to any aspect of the images. EXPOSURE Two still images drawn from advertisements for healthy meals at McDonald’s and BK. MAIN OUTCOMES AND MEASURES Children’s responses were independently content coded to food category by 2 researchers. RESULTS Among the 99 children participating, only 51 (52%) and 69 (70%) correctly identified milk from the McDonald’s and BK images, respectively, with a significantly greater percentage correct (P = .02 for both) among older children. The children’s recall of apples was significantly different by restaurant, with 79 (80%) mentioning apples when describing the McDonald’s image and only 10 (10%) for the BK image (P < .001). The percentage correct was not associated with age in either case. Conversely, although french fries were not featured in either image, 80 children (81%) recalled french fries after viewing the BK advertisement. CONCLUSIONS AND RELEVANCE Of the 4 healthy food images, only depiction of apples by McDonald’s was communicated adequately to the target audience. Representations of milk were inadequately communicated to preliterate children. Televised depictions of apple slices by BK misled the children in this study, although no action was taken by government or self-regulatory bodies.
Immigration-related concerns can impact health and are an important consideration while caring for a multinational Latinx immigrant community. Patients and caregivers waiting for a non-urgent clinic ...appointment were randomly screened with one of two social risk screening tools. One tool included a question about “any health or stability concerns related to immigration status.” The other tool did not include an immigration health question. Immediately following, respondents were invited to participate in a semi-structured interview regarding their social risk screening experience. 201 screens were completed, and 20 patients agreed to an interview. There were no significant sociodemographic differences between groups. Of those screened for immigration, 11% reported a concern. In both arms, interviewees felt that social risk screening was acceptable in a clinic setting. Questions about immigration are timely, important, and relevant, and can be considered when implementing social assessments in communities where there are high levels of trust in providers.
Over the last decade, WCE has established itself as a valuable test for imaging the small intestine. It is a safe and relatively easy procedure to perform that can provide valuable information in the ...diagnosis of small-bowel conditions. Its applications still remain limited within the esophagus and colon. Future developments may include improving visualization within the esophagus and developing technologies that may allow manipulation of the capsule within the GI tract and biopsy capabilities.
Respiratory syncytial virus (RSV) infection in lung transplant (LTx) patients is associated with an increased incidence of bronchiolitis obliterans syndrome (BOS). ALN-RSV01 is a small interfering ...RNA targeting RSV replication that was shown in an earlier Phase 2a trial to be safe and to reduce the incidence of BOS when compared with placebo.
We performed a Phase 2b randomized, double-blind, placebo-controlled trial in RSV-infected LTx patients to examine the impact of ALN-RSV01 on the incidence of new or progressive BOS. Subjects were randomized (1:1) to receive aerosolized ALN-RSV01 or placebo daily for 5 days.
Of 3,985 symptomatic patients screened, 218 were RSV-positive locally, of whom 87 were randomized to receive ALN-RSV01 or placebo (modified intention-to-treat mITT cohort). RSV infection was confirmed by central laboratory in 77 patients (ALN-RSV01, n = 44; placebo, n = 33), which comprised the primary analysis cohort (central mITT mITTc). ALN-RSV01 was found to be safe and well-tolerated. At Day 180, in ALN-RSV01-treated patients, compared with placebo, in the mITTc cohort there was a trend toward a decrease in new or progressive BOS (13.6% vs 30.3%, p = 0.058), which was significant in the per-protocol cohort (p = 0.025). Treatment effect was enhanced when ALN-RSV01 was started <5 days from symptom onset, and was observed even without ribavirin treatment. There was no significant impact on viral parameters or symptom scores.
These results confirm findings of the earlier Phase 2a trial and provide further support that ALN-RSV01 reduces the risk of BOS after RSV in LTx recipients.
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