The Multi-Component Nature of the Vela Pulsar Nonthermal X-ray Spectrum

We report on our analysis of a 274 ks observation of the Vela pulsar with the Rossi X-Ray Timing Explorer (RXTE). The double-peaked, pulsed emission at 2 - 30 keV, which we had previously detected during a 93 ks observation, is confirmed with much improved statistics. There is now clear evidence, both in the spectrum and the light curve, that the emission in the RXTE band is a blend of two separate non-thermal components. The spectrum of the harder component connects smoothly with the OSSE, COMPTEL and EGRET spectrum and the peaks in the light curve are in phase coincidence with those of the high-energy light curve. The spectrum of the softer component is consistent with an extrapolation to the pulsed optical flux, and the second RXTE pulse is in phase coincidence with the second optical peak. In addition, we see a peak in the 2-8 keV RXTE pulse profile at the radio phase.Comment: 12 pages, 3 figures, accepted for publication in Astrophysical Journa

Intracluster medium of the merging cluster Abell 3395

We present a detailed imaging and spectral analysis of the merging environment of the bimodal cluster A3395 using X-ray and radio observations. X-ray images of the cluster show five main constituents of diffuse emission : A3395 NE, A3395 SW, A3395 NW, A3395 W, and a filament connecting NE to W. X-ray surface-brightness profiles of the cluster did not show any shock fronts in the cluster. Temperature and entropy maps show high temperature and high entropy regions in the W, the NW, the filament and between the NE and SW subclusters. The NE, SW and W components have X-ray bolometric luminosities similar to those of rich clusters of galaxies but have relatively higher temperatures. Similarly, the NW component has X-ray bolometric luminosity similar to that of isolated groups but with much higher temperature. It is, therefore, possible that all the components of the cluster have been heated by the ongoing mergers. The NE subcluster is the most massive and luminous constituent and other subclusters are found to be gravitationally bound to it. The W component is most probably either a clump of gas stripped off the SW due to ram pressure or a separate subcluster that has merged or is merging with the SW. No X-ray cavities are seen associated with the Wide Angle Tailed (WAT) radio source near the centre of the SW subcluster. Minimum energy pressure in the radio emission-peaks of the WAT galaxy is comparable with the external thermal pressure. The radio spectrum of the WAT suggests a spectral age of ~10Myr

Acupuncture for chronic neck pain: a pilot for a randomised controlled trial

Background: Acupuncture is increasingly being used for many conditions including chronic neck pain. However the evidence remains inconclusive, indicating the need for further well-designed research. The aim of this study was to conduct a pilot randomised controlled parallel arm trial, to establish key features required for the design and implementation of a large-scale trial on acupuncture for chronic neck pain. Methods: Patients whose GPs had diagnosed neck pain were recruited from one general practice, and randomised to receive usual GP care only, or acupuncture ( up to 10 treatments over 3 months) as an adjunctive treatment to usual GP care. The primary outcome measure was the Northwick Park Neck Pain Questionnaire (NPQ) at 3 months. The primary analysis was to determine the sample size for the full scale study. Results: Of the 227 patients with neck pain identified from the GP database, 28 (12.3%) consenting patients were eligible to participate in the pilot and 24 (10.5%) were recruited to the trial. Ten patients were randomised to acupuncture, receiving an average of eight treatments from one of four acupuncturists, and 14 were randomised to usual GP care alone. The sample size for the full scale trial was calculated from a clinically meaningful difference of 5% on the NPQ and, from this pilot, an adjusted standard deviation of 15.3%. Assuming 90% power at the 5% significance level, a sample size of 229 would be required in each arm in a large-scale trial when allowing for a loss to follow-up rate of 14%. In order to achieve this sample, one would need to identify patients from databases of GP practices with a total population of 230,000 patients, or approximately 15 GP practices roughly equal in size to the one involved in this study (i.e. 15,694 patients). Conclusion: This pilot study has allowed a number of recommendations to be made to facilitate the design of a large-scale trial, which in turn will help to clarify the existing evidence base on acupuncture for neck pain

Barriers to Insulin Initiation: The Translating Research Into Action for Diabetes Insulin Starts Project

OBJECTIVE Reasons for failing to initiate prescribed insulin (primary nonadherence) are poorly understood. We investigated barriers to insulin initiation following a new prescription. RESEARCH DESIGN AND METHODS We surveyed insulin-naïve patients with poorly controlled type 2 diabetes, already treated with two or more oral agents who were recently prescribed insulin. We compared responses for respondents prescribed, but never initiating, insulin (n = 69) with those dispensed insulin (n = 100). RESULTS Subjects failing to initiate prescribed insulin commonly reported misconceptions regarding insulin risk (35% believed that insulin causes blindness, renal failure, amputations, heart attacks, strokes, or early death), plans to instead work harder on behavioral goals, sense of personal failure, low self-efficacy, injection phobia, hypoglycemia concerns, negative impact on social life and job, inadequate health literacy, health care provider inadequately explaining risks/benefits, and limited insulin self-management training. CONCLUSIONS Primary adherence for insulin may be improved through better provider communication regarding risks, shared decision making, and insulin self-management training

The Relativistic Jet-accretion Flow-wind Connection in Mrk 231

Long-term radio monitoring of the broad absorption line (BAL) quasar Mrk 231 at 17.6 GHz detected a strong flare in 2015. This triggered four epochs of Very Long Baseline Array (VLBA) observations from 8.4 to 43 GHz as well as three epochs of X-ray observations with NuSTAR and two with XMM over a 15 week period. Two ejected components were detected by the VLBA observations. A conservative lower bound on the apparent speed of the first ejection is attained by assuming that it was ejected when the flare began, v app > 3.15c. Serendipitous far-UV Hubble Space Telescope observations combined with our long-term radio monitoring seem to indicate that episodes of relativistic ejections suppress flux that is emitted at wavelengths shortward of the peak of the far-UV spectral energy distribution, similar to what has been observed in radio-loud quasars. Episodes of strong jet production also seem to suppress the high-ionization BAL wind seen in weak jet states. We found a statistically significant increase (~25%) of the 3-12 keV flux during the radio flare relative to a quiescent radio state. This is explained by an ultra-fast (~0.06c) X-ray-absorbing photoionized wind that is significantly detected only in the low-radio state (similar to Galactic black holes). Mrk 231 is becoming more radio loud. We found that the putative parsec-scale radio lobe doubled in brightness in nine years. Furthermore, large flares are more frequent, with three major flares occurring at ~2 year intervals

Western Pacific atmospheric nutrient deposition fluxes, their impact on surface ocean productivity

The atmospheric deposition of both macronutrients and micronutrients plays an important role in driving primary productivity, particularly in the low-latitude ocean. We report aerosol major ion measurements for five ship-based sampling campaigns in the western Pacific from similar to 25 degrees N to 20 degrees S and compare the results with those from Atlantic meridional transects (similar to 50 degrees N to 50 degrees S) with aerosols collected and analyzed in the same laboratory, allowing full incomparability. We discuss sources of the main nutrient species (nitrogen (N), phosphorus (P), and iron (Fe)) in the aerosols and their stoichiometry. Striking north-south gradients are evident over both basins with the Northern Hemisphere more impacted by terrestrial dust sources and anthropogenic emissions and the North Atlantic apparently more impacted than the North Pacific. We estimate the atmospheric supply rates of these nutrients and the potential impact of the atmospheric deposition on the tropical western Pacific. Our results suggest that the atmospheric deposition is P deficient relative to the needs of the resident phytoplankton. These findings suggest that atmospheric supply of N, Fe, and P increases primary productivity utilizing some of the residual excess phosphorus (P*) in the surface waters to compensate for aerosol P deficiency. Regional primary productivity is further enhanced via the stimulation of nitrogen fixation fuelled by the residual atmospheric iron and P*. Our stoichiometric calculations reveal that a P* of 0.1 mu mol L-1 can offset the P deficiency in atmospheric supply for many months. This study suggests that atmospheric deposition may sustain similar to 10% of primary production in both the western tropical Pacific

Aerosol Mixing State: Measurements, Modeling, and Impacts

Atmospheric aerosols are complex mixtures of different chemical species, and individual particles exist in many different shapes and morphologies. Together, these characteristics contribute to the aerosol mixing state. This review provides an overview of measurement techniques to probe aerosol mixing state, discusses how aerosol mixing state is represented in atmospheric models at different scales, and synthesizes our knowledge of aerosol mixing state’s impact on climate‐relevant properties, such as cloud condensation and ice nucleating particle concentrations, and aerosol optical properties. We present these findings within a framework that defines aerosol mixing state along with appropriate mixing state metrics to quantify it. Future research directions are identified, with a focus on the need for integrating mixing state measurements and modeling.Key PointsWe define aerosol mixing state and connect it to the physicochemical properties of aerosol particlesWe discuss existing measurements and models to understand chemical and physicochemical mixing stateWe explain the connection between aerosol mixing state and climate‐relevant aerosol propertiesPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150540/1/rog20184_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150540/2/rog20184.pd

Mitoxantrone pleurodesis to palliate malignant pleural effusion secondary to ovarian cancer

BACKGROUND: Advanced ovarian cancer is the leading non-breast gynaecologic cause of malignant pleural effusion. Aim of this study was to assess the efficacy of mitoxantrone sclerotherapy as a palliative treatment of malignant pleural effusions due to ovarian cancer. METHODS: Sixty women with known ovarian cancer and malignant recurrent symptomatic pleural effusion were treated with chest tube drainage followed by intrapleural mitoxantrone sclerotherapy. Survival, complications and response to pleurodesis were recorded. The data are expressed as the mean ± SEM and the median. RESULTS: The mean age of the entire group was 64 ± 11,24 years. The mean interval between diagnosis of ovarian cancer and presentation of the effusion was 10 ± 2,1 months. Eighteen patients (30%) had pleural effusion as the first evidence of recurrence. The mean volume of effusion drained was 1050 ± 105 ml and chest tube was removed within 4 days in 75% of patients. There were no deaths related to the procedure. Side effects of chemical pleurodesis included fever (37–38,5°C) chest pain, nausea and vomiting. At 30 days among 60 treated effusions, there was an 88% overall response rate, including 41 complete responses and 12 partial responses. At 60 days the overall response was 80% (38 complete responses and 10 partial responses). The mean survival of the entire population was 7,5 ± 1,2 months. CONCLUSIONS: Mitoxantrone is effective in the treatment of malignant pleural effusion secondary to ovarian cancer without causing significant local or systemic toxicity