4,569 research outputs found
Station keeping of high power communication satellites
Station keeping of high power communication satellite
Titanium honeycomb structure
A brazed titanium honeycomb sandwich system for supersonic transport wing cover panels provides the most efficient structure spanwise, chordwise, and loadwise. Flutter testing shows that high wing stiffness is most efficient in a sandwich structure. This structure also provides good thermal insulation if liquid fuel is carried in direct contact with the wing structure in integral fuel tanks
State-of-the-art survey of dissimilar metal joining by solid state welding
State-of-the-art of dissimilar metal joining by solid state diffusion bonding and roll and press welding, emphasizing stainless steel and aluminum allo
Biological maturation and match running performance: A national football (soccer) federation perspective
© 2019 Sports Medicine Australia Objectives: To examine the influence of maturation and its interaction with playing position upon physical match performances in U15 footballers from a national federation. Design: Observational study. Methods: 278 male outfield players competing in a national tournament were assessed for somatic maturity and match physical performances according to playing position. Stature, sitting height, and body mass were measured and entered into an algorithm to estimate the age at peak height velocity (APHV). Players match movements were recorded by Global Positioning System devices (10 Hz), to determine peak speed, and total- (TD), low-speed running (LSR; ≤13.0 km h−1), high-speed running (HSR; 13.1–16.0 km h−1), very high-speed running (VHSR; 16.1–20.0 km h−1) and sprint distances (SPR; >20.0 km h−1) expressed relative to match exposure (m min−1). Results: Linear-mixed models using log transformed response variables revealed a significant contribution of estimated APHV upon TD (1.01; 95% CI: 0.99–1.02 m·min−1; p < 0.001), HSR (1.05; 95% CI: 0.98–1.13 m min−1; p < 0.001) and VHSR (1.07; 95% CI: 1.00–1.14 m min−1; p = 0.047). An increase by one year in APHV was associated with an increase of 0.6, 5.4 and 6.9% in TD, HSR and VHSR respectively. No effects of APHV were observed for LSR, SPR, and peak speed. Further, no APHV effects were observed relative to players’ field position. Conclusions: Later maturing players covered substantially more higher-intensity (HSR and VHSR) running in matches, irrespective of playing position. The greater match intensity of later maturing players may inform talent identification and athletic development processes within a national federation
A systematic review of assessment approaches to predict opioid misuse in people with cancer.
CONTEXT: Cancer prevalence is increasing, with many patients requiring opioid analgesia. Clinicians need to ensure patients receive adequate pain relief. However, opioid misuse is widespread, and cancer patients are at risk. OBJECTIVES: This study aims (1) to identify screening approaches that have been used to assess and monitor risk of opioid misuse in patients with cancer; (2) to compare the prevalence of risk estimated by each of these screening approaches; and (3) to compare risk factors among demographic and clinical variables associated with a positive screen on each of the approaches. METHODS: Medline, Cochrane Controlled Trial Register, PubMed, PsycINFO, and Embase databases were searched for articles reporting opioid misuse screening in cancer patients, along with handsearching the reference list of included articles. Bias was assessed using tools from the Joanna Briggs Suite. RESULTS: Eighteen studies met the eligibility criteria, evaluating seven approaches: Urine Drug Test (UDT) (n = 8); the Screener and Opioid Assessment for Patients with Pain (SOAPP) and two variants, Revised and Short Form (n = 6); the Cut-down, Annoyed, Guilty, Eye-opener (CAGE) tool and one variant, Adapted to Include Drugs (n = 6); the Opioid Risk Tool (ORT) (n = 4); Prescription Monitoring Program (PMP) (n = 3); the Screen for Opioid-Associated Aberrant Behavior Risk (SOABR) (n = 1); and structured/specialist interviews (n = 1). Eight studies compared two or more approaches. The rates of risk of opioid misuse in the studied populations ranged from 6 to 65%, acknowledging that estimates are likely to have varied partly because of how specific to opioids the screening approaches were and whether a single or multi-step approach was used. UDT prompted by an intervention or observation of aberrant opioid behaviors (AOB) were conclusive of actual opioid misuse found to be 6.5-24%. Younger age, found in 8/10 studies; personal or family history of anxiety or other mental ill health, found in 6/8 studies; and history of illicit drug use, found in 4/6 studies, showed an increased risk of misuse. CONCLUSIONS: Younger age, personal or familial mental health history, and history of illicit drug use consistently showed an increased risk of opioid misuse. Clinical suspicion of opioid misuse may be raised by data from PMP or any of the standardized list of AOBs. Clinicians may use SOAPP-R, CAGE-AID, or ORT to screen for increased risk and may use UDT to confirm suspicion of opioid misuse or monitor adherence. More research into this important area is required. SIGNIFICANCE OF RESULTS: This systematic review summarized the literature on the use of opioid misuse risk approaches in people with cancer. The rates of reported risk range from 6 to 65%; however, true rate may be closer to 6.5-24%. Younger age, personal or familial mental health history, and history of illicit drug use consistently showed an increased risk of opioid misuse. Clinicians may choose from several approaches. Limited data are available on feasibility and patient experience. PROSPERO registration number. CRD42020163385
Quantifying uncertainties due to optical potentials in one-neutron knockout reactions
One-neutron knockout reactions have been widely used to extract information
about the single-particle structure of nuclei from the valley of stability to
the driplines. The interpretation of knockout data relies on reaction models,
where the uncertainties are typically not accounted for. In this work we
quantify uncertainties of optical potentials used in these reaction models and
propagate them, for the first time, to knockout observables using a Bayesian
analysis. We study two reactions in the present paper, the first of which
involves a loosely-bound halo projectile, Be, and the second a
tightly-bound projectile, C. We first quantify the parametric
uncertainties associated with phenomenological optical potentials.
Complementing to this approach, we also quantify the model uncertainties
associated with the chiral forces that can be used to construct microscopic
optical potentials. For the phenomenological study, we investigate the impact
of the imaginary terms of the optical potential on the breakup and stripping
components of the knockout cross sections as well as the impact of the angular
range. For the Be case, the theoretical uncertainty from the
phenomenological method is on the order of the experiment uncertainty on the
knockout observables; however, for the C case, the theoretical
uncertainty is significantly larger. The widths of the confidence intervals for
the knockout observables obtained for the microscopic study and the
phenomenological approach are of similar order of magnitude. Based on this work
we conclude that structure information inferred from the ratio of the knockout
cross sections, will carry a theoretical uncertainty of at least for
halo nuclei and at least for tightly-bound nuclei.Comment: 12 pages (including 2 of supplemental material and 1 of reference), 5
figures, 2 table
Dual-Frequency Observations of 140 Compact, Flat-Spectrum Active Galactic Nuclei for Scintillation-Induced Variability
The 4.9 GHz Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey
detected a drop in Interstellar Scintillation (ISS) for sources at redshifts z
> 2, indicating an apparent increase in angular diameter or a decrease in flux
density of the most compact components of these sources, relative to their
extended emission. This can result from intrinsic source size effects or
scatter broadening in the Intergalactic Medium (IGM), in excess of the expected
(1+z)^0.5 angular diameter scaling of brightness temperature limited sources
due to cosmological expansion. We report here 4.9 GHz and 8.4 GHz observations
and data analysis for a sample of 140 compact, flat-spectrum sources which may
allow us to determine the origin of this angular diameter-redshift relation by
exploiting their different wavelength dependences. In addition to using ISS as
a cosmological probe, the observations provide additional insight into source
morphologies and the characteristics of ISS. As in the MASIV Survey, the
variability of the sources is found to be significantly correlated with
line-of-sight H-alpha intensities, confirming its link with ISS. For 25
sources, time delays of about 0.15 to 3 days are observed between the
scintillation patterns at both frequencies, interpreted as being caused by a
shift in core positions when probed at different optical depths. Significant
correlation is found between ISS amplitudes and source spectral index; in
particular, a large drop in ISS amplitudes is observed at spectral indices of <
-0.4 confirming that steep spectrum sources scintillate less. We detect a
weakened redshift dependence of ISS at 8.4 GHz over that at 4.9 GHz, with the
mean variance at 4-day timescales reduced by a factor of 1.8 in the z > 2
sources relative to the z < 2 sources, as opposed to the factor of 3 decrease
observed at 4.9 GHz. This suggests scatter broadening in the IGM.Comment: 30 pages, 14 figures, accepted for publication in the Astronomical
Journa
- …