256,837 research outputs found

    Multiscaling of galactic cosmic ray flux

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    Multiscaling analysis of differential flux dissipation rate of galactic cosmic rays (Carbon nuclei) is performed in the energy ranges: 56.3-73.4 Mev/nucleon and 183.1-198.7 MeV/nucleon, using the data collected by ACE/CRIS spacecraft instrument for 2000 year. The analysis reveals strong (turbulence-like) intermittency of the flux dissipation rate for the short-term intervals: 1-30 hours. It is also found that type of the intermittency can be different in different energy ranges

    Cosmic Ray Acceleration in Superbubbles and the Composition of Cosmic Rays

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    We review the evidence for cosmic ray acceleration in the superbubble/hot phase of the interstellar medium, and discuss the implications for the composition of cosmic rays and the structure and evolution of the interstellar medium. We show that the bulk of the galactic supernovae, their expanding remnants, together with their metal-rich grain and gas ejecta, and their cosmic ray accelerating shocks, are all confined within the interiors of superbubbles, generated by the multiple supernova explosions of massive stars formed in giant OB associations. This superbubble/hot phase of the ISM provides throughout the age of the Galaxy a cosmic ray source of essentially constant metallicity for acceleration by the shocks of many supernovae over time scales of a few Myr, consistent with both the Be/Fe evolution and ACE observations of Ni-59/Co-59. We also show that if the refractory cosmic ray metals come from the sputtering of fast refractory grains then the accompanying scattering of ambient gas by these fast grains can also account for the relative abundance of cosmic ray volatiles.Comment: latex 8 pages, to appear in Proc. ACE-2000 Symp., AIP Conf. Pro

    The Cosmic Ray - X-ray Connection: Effects of Nonlinear Shock Acceleration on Photon Production in SNRs

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    Cosmic-ray production in young supernova remnant (SNR) shocks is expected to be efficient and strongly nonlinear. In nonlinear, diffusive shock acceleration, compression ratios will be higher and the shocked temperature lower than test-particle, Rankine-Hugoniot relations predict. Furthermore, the heating of the gas to X-ray emitting temperatures is strongly coupled to the acceleration of cosmic-ray electrons and ions, thus nonlinear processes which modify the shock, influence the emission over the entire band from radio to gamma-rays and may have a strong impact on X-ray line models. Here we apply an algebraic model of nonlinear acceleration, combined with SNR evolution, to model the radio and X-ray continuum of Kepler's SNR.Comment: 7 pages including 4 figures; to appear in ``The Acceleration and Transport of Energetic Particles Observed in the Heliosphere,'' Proceedings of the ACE-2000 Symposium held on January 5 - 8, 2000, Indian Springs, C

    What can GLAST say about the origin of cosmic rays in other galaxies ?

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    Gamma rays in the band from 20 MeV to 300 GeV, used in combination with data from radio and X-ray bands, provide a powerful tool for studying the origin of cosmic rays in our sister galaxies Andromeda and the Magellanic Clouds. Gamma-ray Large Area Space Telescope (GLAST) will spatially resolve these galaxies and measure the spectrum and intensity of diffuse gamma radiation from the collisions of cosmic rays with gas and dust in them. Observations of Andromeda will give an external perspective on a spiral galaxy like the Milky Way. Observations of the Magellanic Clouds will permit a study of cosmic rays in dwarf irregular galaxies, where the confinement is certainly different and the massive star formation rate is much greater.Comment: 4 pages including 6 figures; to appear in Proc. ACE-2000 Symp. "The Acceleration and Transport of Energetic Particles Observed in the Heliosphere" (Jan. 5-8, 2000, Indian Wells, CA), AIP Conf. Proc. More details can be found at the LHEA GLAST page at http://lhea-glast.gsfc.nasa.gov/pub/science/index.htm

    Are non-allergic drug reactions commonly documented as medication “allergies”? A national cohort of Veterans\u27 admissions from 2000 to 2014

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    Purpose: Adverse drug reactions (ADRs) including medication allergies are not well-described among large national cohorts. This study described the most common documented medication allergies and their reactions among a national cohort of Veterans Affairs (VA) inpatients. Methods: We evaluated inpatient admissions in any VA Medical Center from 1 January 2000 to 31 December 2014. Each admission was linked with allergy history preceding or upon admission. Individual drugs were aggregated into drug class category including: penicillins, sulfonamides, angiotensin converting enzyme (ACE) inhibitors, opiates, HMG-CoA reductase inhibitors (“statins”) and non-steroidal anti-inflammatory inhibitors (NSAID). Results were reported in aggregate and over time. Results: Approximately ~10.8 million inpatient admissions occurred from 2000 to 2014. We found the most commonly reported allergy drug classes were penicillins (13%, n = 1 410 080), opiates (9.1%, n = 984 978), ACE inhibitors (5.7%, n = 618 075) sulfonamides (5.1%, n = 558 653), NSAIDs (5.1%, n = 551 216) and statins (3.6%, n  = 391 983). Several allergy histories increased over time including opiates (6.2 to 11.2%), ACE inhibitors (1.3 to 10.2%), statins (0.3 to 7.3%) and NSAIDs (3.9 to 6.0%). Rash was the most commonly documented reaction on reports for penicillins (25.5%, n = 371 825), sulfonamides (25.6%, n = 165 954) and NSAIDs (10.3%, n = 65 741). The most common reaction for opiates was nausea/vomiting (17.9%, n = 211 864), cough/coughing for ACE inhibitors (41.0%, n = 270 537) and muscle pain/myalgia for statins (34.1%, n = 186 565). Conclusions: We report that penicillins and opiates are the most commonly documented drug allergies among VA inpatients, but other drug classes such as ACE inhibitors, statins and NSAIDs are becoming increasingly common. Clinicians also commonly document non-allergic ADRs in the allergy section such as cough or myalgia. Copyright © 2016 John Wiley & Sons, Ltd

    Pengaruh Penambahan MasterGlenium ACE® 8595 dengan Pengurangan Kadar Air 37.5% dan Kadar Semen Rencana 409.80 kg/m3 Terhadap Kuat Tekan Beton

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    MasterGlenium ACE® 8595 is a Type F chemical that serves to reduce the amount of mixing water, improve workability and improve concrete quality. The purpose of this study was to find out the effect of adding MasterGlenium ACE® 8595 with a reduction in water content of 37.5% and a plan cement level of 409.80 kg / m2. The research was conducted in the laboratory using the DOE (Department of Environment) method in accordance with SNI 03-2834-2000 with a test object in the form of a concrete cylinder diameter of 150 mm and a height of 300 mm. MasterGlenium ACE® 8595 tested on concrete age 7 days 3 sample, and 28 days 5 sample. Variations in the dose of addition of MasterGlenium ACE® 8595 used 0.54%, 0.81%, 1.08%, 1.35%, 1.62%, 1.89% and 2.16% of cement weight. The test results of a strong concrete press normal at 28 days amounted to 29.77 MPa.  The test results of a strong concrete press normal at 28 days amounted to 29.77 MPa.  The results of the test are strong concrete press with the addition of MasterGlenium ACE® 8595 amounting to 51.61 MPa, 53.53 MPa, 45.95 MPa, 49.80 MPa, 41.25 MPa, 40.80 MPa, and 39.27 MPa. Based on the results of the test, the use of MasterGlenium ACE® 8595 in concrete will increase the strength of the press, workability, and age coefficient

    Models for Galactic cosmic-ray propagation

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    A new numerical model of particle propagation in the Galaxy has been developed, which allows the study of cosmic-ray and gamma-ray production and propagation in 2D or 3D, including a full reaction network. This is a further development of the code which has been used for studies of cosmic ray reacceleration, Galactic halo size, antiprotons and positrons in cosmic rays, the interpretation of diffuse continuum gamma rays, and dark matter. In this paper we illustrate recent results focussing on B/C, sub-Fe/Fe, ACE radioactive isotope data, source abundances and antiprotons. From the radioactive nuclei we derive a range of 3-7 kpc for the height of the cosmic-ray halo.Comment: Invited talk at the 33rd COSPAR Scientific Assembly (Warsaw 2000); 10 pages including 10 ps-figures and 2 tables, latex2e, uses cospar.sty. To appear in Advances in Space Research 2001. More details can be found at http://www.gamma.mpe-garching.mpg.de/~aws/aws.htm

    Adult Comorbidity Evaluation 27 score as a predictor of survival in endometrial cancer patients

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    BACKGROUND The incidence of endometrial cancer increases with age and is associated with medical comorbidities such as obesity and diabetes. While a few cohort studies of less than 500 patients showed an association between comorbidity and survival in endometrial cancer patients, the degree of association needs to be better described. The Adult Comorbidity Evaluation 27 (ACE-27) is a validated comorbidity instrument that provides a score (0–3) based on the number and severity of medical comorbidities. OBJECTIVE This study was performed to explore the association between medical comorbidities and survival of endometrial cancer patients. STUDY DESIGN Patients diagnosed with endometrial cancer from 2000–2012 were identified from the prospectively maintained Siteman Cancer Center tumor registry. Patients undergoing primary surgical treatment for endometrioid, serous and clear cell endometrial carcinoma were included. Patients primarily treated with radiation, chemotherapy or hormone therapy were excluded. Patients with uterine sarcomas or neuroendocrine tumors were excluded. Patients with missing ACE-27 scores were also excluded from analysis. Information including patient demographics, ACE-27 score, tumor characteristics, adjuvant treatment and survival data were extracted from the database. The association of ACE-27 and overall as well as recurrence-free survival was explored in a multivariable Cox regression analysis after controlling for variables found to be significantly associated with survival in univariable analysis. RESULTS A total of 2073 patients with a median age of 61 years (range 20–94) at diagnosis were identified. ACE-27 score was 0, 1, 2 and 3 in 22%, 38%, 28% and 12% of patients, respectively. Stage distribution was I (73%), II (5%), III (15%) and IV (7%) and grade distribution was 1 (52%), 2 (23%) and 3 (25%). Most patients had endometrioid histology (87%) followed by serous (11%) and clear cell (3%). The median OS for the entire cohort was 54 months [95% confidence interval (CI) 3, 154 months] and median PFS was 50 months [95% CI 2, 154 months]., On univariable analysis, age, race, marital status, stage, grade, histology and treatment type were significantly associated with overall survival and recurrence-free survival. After adjusting for these covariates, patients with ACE-27 score of 2 had a 52% higher risk of death [95% CI 1.16, 2.00] and patients with ACE-27 score of 3 had a 2.35-fold increased risk of death [95% CI 1.73, 3.21] compared to patients with an ACE-27 score of 0. Similarly, patients with ACE-27 score of 2 had a 38% higher risk of recurrence [95% CI 1.07, 1.78] and patients with ACE-27 score of 3 had a 2.05-fold increased risk of recurrence [95% CI 1.53, 2.75] compared to patients with an ACE-27 score of 0. We found no interaction between ACE-27 score and age, stage or treatment type. CONCLUSIONS Our findings demonstrate the importance of comorbidities in estimating the prognosis of endometrial cancer patients, even after adjusting for age and known tumor-specific prognostic factors like stage, grade, histology and adjuvant treatment

    Semiparametric Sensitivity Analysis: Unmeasured Confounding In Observational Studies

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    Establishing cause-effect relationships from observational data often relies on untestable assumptions. It is crucial to know whether, and to what extent, the conclusions drawn from non-experimental studies are robust to potential unmeasured confounding. In this paper, we focus on the average causal effect (ACE) as our target of inference. We generalize the sensitivity analysis approach developed by Robins et al. (2000), Franks et al. (2020) and Zhou and Yao (2023. We use semiparametric theory to derive the non-parametric efficient influence function of the ACE, for fixed sensitivity parameters. We use this influence function to construct a one-step bias-corrected estimator of the ACE. Our estimator depends on semiparametric models for the distribution of the observed data; importantly, these models do not impose any restrictions on the values of sensitivity analysis parameters. We establish sufficient conditions ensuring that our estimator has root-n asymptotics. We use our methodology to evaluate the causal effect of smoking during pregnancy on birth weight. We also evaluate the performance of estimation procedure in a simulation study

    Charged particle composition in the inner heliosphere during the rise to maximum of Solar Cycle 23

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    Flux distributions and abundances relative to oxygen of interplanetary ions (Z>1)(Z>1) are statistically studied and compared for measurements made at 1 and at ∼5 AU on the ACE and the Ulysses spacecraft near the ecliptic plane. Over the nearly two year interval studied, the distributions of the relative abundances and the fluxes of particles at the two locations are found to be approximately log normal. The statistical distributions of the relative abundances are found to be similar at the two helioradii. On a statistical basis, the fluxes at Ulysses times the distance of the measurements appear to be proportional to the fluxes at ACE. This radial dependence of the fluxes is consistent with the interpretation that, statistically, the ion parallel diffusion coefficient is large. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87340/2/169_1.pd
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