3,140 research outputs found
New Proposal to Iran: Will It Be Enough to Defuse the Nuclear Crisis?
This BASIC Note assesses the progress of transatlantic diplomacy toward Iran on nuclear issues. On June 6, Iran was presented with a revised package of incentives to persuade it to curb its uranium enrichment program. The authors argued previously that the earlier E3/EU proposal was vague on incentives and heavy on demands. (See BASIC Note, August 11, 2005 at http://www.basicint.org/pubs/Notes/BN050811-IranEU.htm). In this article, the authors suggest that if the June 6 proposal had been offered a year ago (or better still two years ago), much of the recent damage to diplomatic relations between Iran and the West could have been avoided
Effective Inner Radius of Tilted Black Hole Accretion Disks
One of the primary means of determining the spin of an astrophysical black
hole is by actually measuring the inner radius of a surrounding accretion disk
and using that to infer the spin. By comparing a number of different estimates
of the inner radius from simulations of tilted accretion disks with differing
black-hole spins, we show that such a procedure can give quite wrong answers.
Over the range 0 <= a/M <= 0.9, we find that, for moderately thick disks (H/r ~
0.2) with modest tilt (15 degrees), the inner radius is nearly independent of
spin. This result is likely dependent on tilt, such that for larger tilts, it
may even be that the inner radius would increase with increasing spin. In the
opposite limit, we confirm through numerical simulations of untilted disks
that, in the limit of zero tilt, the inner radius recovers approximately the
expected dependence on spin.Comment: 5 pages, 4 figures, accepted to ApJ Letter
The Characterization of Cell Line Crl-2335 as a Basal-Like Breast Carcinoma Model
Basal-like breast cancer has been reported to be the most aggressive and deadly carcinoma sub-type. Patients diagnosed with this subtype have a less than 50% five-year survival. In addition, many studies have reported that this sub-type is more prevalent in specific ethnic groups and is believed to be a key factor that drives certain ethnic disparities in mortality. In order to effectively study this sub-type and determine unique gene expression and biochemical pathways which sustain this cancerâs growth, we sought to identify human breast cancer cell lines that represent a model for the basal-like subtype. Here, we report our findings which indicate the African American cell line CRL-2335 is a true representative of basal-like breast carcinoma
A Church-based Diabetes Self-management Education Program for African Americans With Type 2 Diabetes
INTRODUCTION: Diabetes self-management education interventions in community gathering places have been moderately effective, but very few studies of intervention effectiveness have been conducted among African Americans with type 2 diabetes. This paper describes a church-based diabetes self-management education intervention for African Americans, a randomized controlled trial to evaluate the intervention, and baseline characteristics of study participants. METHODS: A New DAWN: Diabetes Awareness & Wellness Network was conducted among 24 churches of varying size in North Carolina. Each church recruited congregants with type 2 diabetes and designated a diabetes advisor, or peer counselor, to be part of the intervention team. Participants were enrolled at each church and randomized as a unit to either the special intervention or the minimal intervention. The special intervention included one individual counseling visit, twelve group sessions, three postcard messages from the participant's diabetes care provider, and twelve monthly telephone calls from a diabetes advisor. Baseline data included measures of weight, hemoglobin A1c, blood pressure, physical activity, dietary and diabetes self-care practices, and psychosocial factors. The study to evaluate the intervention (from enrollment visit to last follow-up) began in February 2001 and ended in August 2003. RESULTS: Twenty-four churches (with 201 total participants) were randomized. Sixty-four percent of the participants were women. On average, the participants were aged 59 years and sedentary. They had an average of 12 years of education, had been diagnosed with diabetes for 9 years, had a body mass index of 35, had a hemoglobin A1c level of 7.8%, and had a reported dietary intake of 39% of calories from fat. CONCLUSION: A New DAWN is a culturally sensitive, church-based diabetes self-management education program for African Americans with type 2 diabetes that is being evaluated for effectiveness in a randomized controlled trial. The outcomes of A New DAWN will contribute to the literature on community-based interventions for minority populations and help to inform the selection of approaches to improve diabetes care in this population
Advanced composites structural concepts and materials technologies for primary aircraft structures: Design/manufacturing concept assessment
Composite Wing and Fuselage Structural Design/Manufacturing Concepts have been developed and evaluated. Trade studies were performed to determine how well the concepts satisfy the program goals of 25 percent cost savings, 40 percent weight savings with aircraft resizing, and 50 percent part count reduction as compared to the aluminum Lockheed L-1011 baseline. The concepts developed using emerging technologies such as large scale resin transfer molding (RTM), automatic tow placed (ATP), braiding, out-of-autoclave and automated manufacturing processes for both thermoset and thermoplastic materials were evaluated for possible application in the design concepts. Trade studies were used to determine which concepts carry into the detailed design development subtask
Low-Frequency Oscillations in Global Simulations of Black Hole Accretion
We have identified the presence of large-scale, low-frequency dynamo cycles
in a long-duration, global, magnetohydrodynamic (MHD) simulation of black hole
accretion. Such cycles had been seen previously in local shearing box
simulations, but we discuss their evolution over 1,500 inner disk orbits of a
global pi/4 disk wedge spanning two orders of magnitude in radius and seven
scale heights in elevation above/below the disk midplane. The observed cycles
manifest themselves as oscillations in azimuthal magnetic field occupying a
region that extends into a low-density corona several scale heights above the
disk. The cycle frequencies are ten to twenty times lower than the local
orbital frequency, making them potentially interesting sources of low-frequency
variability when scaled to real astrophysical systems. Furthermore, power
spectra derived from the full time series reveal that the cycles manifest
themselves at discrete, narrow-band frequencies that often share power across
broad radial ranges. We explore possible connections between these simulated
cycles and observed low-frequency quasi-periodic oscillations (LFQPOs) in
galactic black hole binary systems, finding that dynamo cycles have the
appropriate frequencies and are located in a spatial region associated with
X-ray emission in real systems. Derived observational proxies, however, fail to
feature peaks with RMS amplitudes comparable to LFQPO observations, suggesting
that further theoretical work and more sophisticated simulations will be
required to form a complete theory of dynamo-driven LFQPOs. Nonetheless, this
work clearly illustrates that global MHD dynamos exhibit quasi-periodic
behavior on timescales much longer than those derived from test particle
considerations.Comment: Version accepted to The Astrophysical Journal, 8 pages, 7 figure
Uptake of soil management practices and experiences with decisions support tools: Analysis of the consultation with the farming community.
The two faces of CD73 in tumor-infiltrating lymphocytes expanded from Liposarcoma
TMP-IL, Department of Translational Molecular Pathology Department of Sarcoma Medical Oncologyhttps://openworks.mdanderson.org/sumexp22/1056/thumbnail.jp
Continuous Infusions of Meropenem in Ambulatory Care: Clinical Efficacy, Safety and Stability
Objectives: Concerns regarding the clinical impact of meropenem instability in continuous infusion (CI) devices may contribute to inconsistent uptake of this method of administration across outpatient parenteral antimicrobial therapy (OPAT) services. Methods: We retrospectively reviewed the clinical efficacy and safety of CIs of meropenem in two Australian tertiary hospitals and assessed its stability under simulated OPAT conditions including in elastomeric infusion devices containing 1% (2.4 g) or 2% (4.8 g) concentrations at either âroom temperatureâ or âcooledâ conditions. Infusate aliquots were assayed at different time-points over 24 hours. Results: Forty-one (82%) of 50 patients had clinical improvement or were cured. Adverse patient outcomes including hemato-, hepato- and nephrotoxicity were infrequent. Cooled infusers with 1% meropenem had a mean 24-hour recovery of 90.3%. Recoveries of 1% and 2% meropenem at room temperature and 2% under cooled conditions were 88%, 83% and 87%, respectively. Patients receiving 1% meropenem are likely to receive >95% of the maximum deliverable dose (MDD) over a 24-hour period whilst patients receiving 2% meropenem should receive 93% and 87% of the MDD under cooled and room temperature conditions, respectively. Conclusions: Meropenem infusers are likely to deliver ~95% MDD and maintain effective plasma concentrations throughout the dosing period. These data reflect our local favourable clinical experience with eropenem CIs
Emergent Mesoscale Phenomena in Magnetized Accretion Disc Turbulence
We study how the structure and variability of magnetohydrodynamic (MHD)
turbulence in accretion discs converge with domain size. Our results are based
on a series of vertically stratified local simulations, computed using the
Athena code, that have fixed spatial resolution, but varying radial and
azimuthal extent (from \Delta R = 0.5H to 16H, where H is the vertical scale
height). We show that elementary local diagnostics of the turbulence, including
the Shakura-Sunyaev {\alpha} parameter, the ratio of Maxwell stress to magnetic
energy, and the ratio of magnetic to fluid stresses, converge to within the
precision of our measurements for spatial domains of radial size Lx \geq 2H. We
obtain {\alpha} = 0.02-0.03, consistent with recent results. Very small domains
(Lx = 0.5H) return anomalous results, independent of spatial resolution. The
convergence with domain size is only valid for a limited set of diagnostics:
larger spatial domains admit the emergence of dynamically important mesoscale
structures. In our largest simulations, the Maxwell stress shows a significant
large scale non-local component, while the density develops long-lived
axisymmetric perturbations (zonal flows) at the 20% level. Most strikingly, the
variability of the disc in fixed-sized patches decreases strongly as the
simulation volume increases. We find generally good agreement between our
largest local simulations and global simulations with comparable spatial
resolution. There is no direct evidence that the presence of curvature terms or
radial gradients in global calculations materially affect the turbulence,
except to perhaps introduce an outer radial scale for mesoscale structures. The
demonstrated importance of mean magnetic fields, seen in both large local and
global simulations implies that the growth and saturation of these fields is
likely of critical importance for the evolution of accretion discs. (abridged)Comment: 18 pages, 20 figures, accepted to MNRA
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