2,753 research outputs found
The need for robust critique of arts and health research: Danceâmovement therapy, girls, and depression
We examine a highly cited randomized controlled trial on dance-movement therapy with adolescent girls with mild depression and examine its treatment in 14 evidence reviews and meta-analyses of dance research. We demonstrate substantial limitations in the trial which seriously undermine the conclusions reached regarding the effectiveness of dance movement therapy in reducing depression. We also show that the dance research reviews vary substantially in their treatment of the study. Some reviews provide a positive assessment of the study and take its findings at face value without critical commentary. Others are critical of the study, identifying significant limitations, but showing marked differences in Cochrane Risk of Bias assessments. Drawing on recent criticisms of systematic reviewing and meta-analysis, we consider how reviews can be so variable and discuss what is needed to improve the quality of primary studies, systematic reviews, and meta-analyses in the field of creative arts and health
Quantum Zeno effect in a probed downconversion process
The distorsion of a spontaneous downconvertion process caused by an auxiliary
mode coupled to the idler wave is analyzed. In general, a strong coupling with
the auxiliary mode tends to hinder the downconversion in the nonlinear medium.
On the other hand, provided that the evolution is disturbed by the presence of
a phase mismatch, the coupling may increase the speed of downconversion. These
effects are interpreted as being manifestations of quantum Zeno or anti-Zeno
effects, respectively, and they are understood by using the dressed modes
picture of the device. The possibility of using the coupling as a nontrivial
phase--matching technique is pointed out.Comment: 11 pages, 4 figure
Cosmic ray tests of a GEM-based TPC prototype operated in Ar-CF4-isobutane gas mixtures
Argon with an admixture of CF4 is expected to be a good candidate for the gas
mixture to be used for a time projection chamber (TPC) in the future linear
collider experiment because of its small transverse diffusion of drift
electrons especially under a strong magnetic field. In order to confirm the
superiority of this gas mixture over conventional TPC gases we carried out
cosmic ray tests using a GEM-based TPC operated mostly in Ar-CF4-isobutane
mixtures under 0 - 1 T axial magnetic fields. The measured gas properties such
as gas gain and transverse diffusion constant as well as the observed spatial
resolution are presented.Comment: 22 pages, 18 figures. Published in Nuclear Instruments and Methods in
Physics Research A. Fig. 3 in the introduction was corrected since it had not
been properly normalized. Minor corrections and no changes in the conclusio
Large salp bloom export from the upper ocean and benthic community response in the abyssal northeast Pacific: Day to week resolution
A large bloom of Salpa spp. in the northeastern Pacific during the spring of 2012 resulted in a major deposition of tunics and fecal pellets on the seafloor at ⌠4000 m depth (Sta. M) over a period of 6 months. Continuous monitoring of this food pulse was recorded using autonomous instruments: sequencing sediment traps, a timeâlapse camera on the seafloor, and a bottomâtransiting vehicle measuring sediment community oxygen consumption (SCOC). These deepâsea measurements were complemented by sampling of salps in the epipelagic zone by California Cooperative Ocean Fisheries Investigations. The particulate organic carbon (POC) flux increased sharply beginning in early March, reaching a peak of 38 mg C mâ2 dâ1 in midâApril at 3400 m depth. Salp detritus started appearing in images of the seafloor taken in March and covered a daily maximum of 98% of the seafloor from late June to early July. Concurrently, the SCOC rose with increased salp deposition, reaching a high of 31 mg C mâ2 dâ1 in late June. A dominant megafauna species, Peniagone sp. A, increased 7âfold in density beginning 7 weeks after the peak in salp deposition. Estimated food supply from salp detritus was 97â327% of the SCOC demand integrated over the 6âmonth period starting in March 2012. Such large episodic pulses of food sustain abyssal communities over extended periods of time
Super-Kamiokande atmospheric neutrino data, zenith distributions, and three-flavor oscillations
We present a detailed analysis of the zenith angle distributions of
atmospheric neutrino events observed in the Super-Kamiokande (SK) underground
experiment, assuming two-flavor and three-flavor oscillations (with one
dominant mass scale) among active neutrinos. In particular, we calculate the
five angular distributions associated to sub-GeV and multi-GeV \mu-like and
e-like events and to upward through-going muons, for a total of 30 accurately
computed observables (zenith bins). First we study how such observables vary
with the oscillation parameters, and then we perform a fit to the experimental
data as measured in SK for an exposure of 33 kTy (535 days). In the two-flavor
mixing case, we confirm the results of the SK Collaboration analysis, namely,
that \nu_\mu\nu_\tau oscillations are preferred over \nu_\mu\nu_e,
and that the no oscillation case is excluded with high confidence. In the
three-flavor mixing case, we perform our analysis with and without the
additional constraints imposed by the CHOOZ reactor experiment. In both cases,
the analysis favors a dominance of the \nu_\mu\nu_\tau channel. Without
the CHOOZ constraints, the amplitudes of the subdominant \nu_\munu_e and
\nu_e\nu_\tau transitions can also be relatively large, indicating that,
at present, current SK data do not exclude sizable \nu_e mixing by themselves.
After combining the CHOOZ and SK data, the amplitudes of the subdominant
transitions are constrained to be smaller, but they can still play a
nonnegligible role both in atmospheric and other neutrino oscillation searches.
In particular, we find that the \nu_e appearance probability expected in long
baseline experiments can reach the testable level of ~15%.Comment: 35 pages (RevTeX), including 20 ps figures (with epsfig.sty
Male tobacco smoke load and non-lung cancer mortality associations in Massachusetts
<p>Abstract</p> <p>Background</p> <p>Different methods exist to estimate smoking attributable cancer mortality rates (Peto and Ezzati methods, as examples). However, the smoking attributable estimates using these methods cannot be generalized to all population sub-groups. A simpler method has recently been developed that can be adapted and applied to different population sub-groups. This study assessed cumulative tobacco smoke damage (smoke load)/non-lung cancer mortality associations across time from 1979 to 2003 among all Massachusetts males and ages 30â74 years, using this novel methodology.</p> <p>Methods</p> <p>Annual lung cancer death rates were used as smoke load bio-indices, and age-adjusted lung/all other (non-lung) cancer death rates were analyzed with linear regression approach. Non-lung cancer death rates include all cancer deaths excluding lung. Smoking-attributable-fractions (SAFs) for the latest period (year 2003) were estimated as: 1-(estimated unexposed cancer death rate/observed rate).</p> <p>Results</p> <p>Male lung and non-lung cancer death rates have declined steadily since 1992. Lung and non-lung cancer death rates were tightly and steeply associated across years. The slopes of the associations analyzed were 1.69 (95% confidence interval (CI) 1.35â2.04, r = 0.90), and 1.36 (CI 1.14â1.58, r = 0.94) without detected autocorrelation (Durbin-Watson statistic = 1.8). The lung/non-lung cancer death rate associations suggest that all-sites cancer death rate SAFs in year 2003 were 73% (Sensitivity Range [SR] 61â82%) for all ages and 74% (SR 61â82%) for ages 30â74 years.</p> <p>Conclusion</p> <p>The strong lung/non-lung cancer death rate associations suggest that tobacco smoke load may be responsible for most prematurely fatal cancers at both lung and non-lung sites. The present method estimates are greater than the earlier estimates. Therefore, tobacco control may reduce cancer death rates more than previously noted.</p
Zeno dynamics yields ordinary constraints
The dynamics of a quantum system undergoing frequent measurements (quantum
Zeno effect) is investigated. Using asymptotic analysis, the system is found to
evolve unitarily in a proper subspace of the total Hilbert space. For spatial
projections, the generator of the "Zeno dynamics" is the Hamiltonian with
Dirichlet boundary conditions.Comment: 6 page
Quantum criticalities in a two-leg antiferromagnetic S=1/2 ladder induced by a staggered magnetic field
We study a two-leg antiferromagnetic spin-1/2 ladder in the presence of a
staggered magnetic field. We consider two parameter regimes: strong (weak)
coupling along the legs and weak (strong) coupling along the rungs. In both
cases, the staggered field drives the Haldane spin-liquid phase of the ladder
towards a Gaussian quantum criticality. In a generalized spin ladder with a
non-Haldane, spontaneously dimerized phase, the staggered magnetic field
induces an Ising quantum critical regime. In the vicinity of the critical
lines, we derive low-energy effective field theories and use these descriptions
to determine the dynamical response functions, the staggered spin
susceptibility and the string order parameter.Comment: 29 pages of revtex, 10 figure
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