Quantifying Absorption in the Transactional Interpretation

The Transactional Interpretation offers a solution to the measurement problem by identifying specific physical conditions precipitating the non-unitary `measurement transition' of von Neumann. Specifically, the transition occurs as a result of absorber response (a process lacking in the standard approach to the theory). The purpose of this Letter is to make clear that, despite recent claims to the contrary, the concepts of `absorber' and `absorber response,' as well as the process of absorption, are physically and quantitatively well-defined in the transactional picture. In addition, the Born Rule is explicitly derived for radiative processes.Comment: Final version, accepted in International Journal of Quantum Foundation

Characteristics of randomized controlled trials of yoga: A bibliometric analysis

© 2014 Cramer et al.; licensee BioMed Central Ltd. Background: A growing number of randomized controlled trials (RCTs) have investigated the therapeutic value of yoga interventions. This bibliometric analysis aimed to provide a comprehensive review of the characteristics of the totality of available randomized yoga trials. Methods: All RCTs of yoga were eligible. Medline/PubMed, Scopus, the Cochrane Library, IndMED, and the tables of content of yoga specialty journals not listed in medical databases were screened through February 2014. Bibliometric data, data on participants, and intervention were extracted and analyzed descriptively. Results: Published between 1975 and 2014, a total of 366 papers were included, reporting 312 RCTs from 23 different countries with 22,548 participants. The median study sample size was 59 (range 8-410, interquartile range = 31, 93). Two hundred sixty-four RCTs (84.6%) were conducted with adults, 105 (33.7%) with older adults and 31 (9.9%) with children. Eighty-four RCTs (26.9%) were conducted with healthy participants. Other trials enrolled patients with one of 63 varied medical conditions; the most common being breast cancer (17 RCTs, 5.4%), depression (14 RCTs, 4.5%), asthma (14 RCTs, 4.5%) and type 2 diabetes mellitus (13 RCTs, 4.2%). Whilst 119 RCTs (38.1%) did not define the style of yoga used, 35 RCTs (11.2%) used Hatha yoga and 30 RCTs (9.6%) yoga breathing. The remaining 128 RCTs (41.0%) used 46 varied yoga styles, with a median intervention length of 9 weeks (range 1 day to 1 year; interquartile range = 5, 12). Two hundred and forty-four RCTs (78.2%) used yoga postures, 232 RCTs (74.4%) used breath control, 153 RCTs (49.0%) used meditation and 32 RCTs (10.3%) used philosophy lectures. One hundred and seventy-four RCTs (55.6%) compared yoga with no specific treatment; 21 varied control interventions were used in the remaining RCTs. Conclusions: This bibliometric analysis presents the most complete up-to-date overview on published randomized yoga trials. While the available research evidence is sparse for most conditions, there was a marked increase in published RCTs in recent years

New CP-violation and preferred-frame tests with polarized electrons

We used a torsion pendulum containing $\sim 9 \times 10^{22}$ polarized electrons to search for CP-violating interactions between the pendulum's electrons and unpolarized matter in the laboratory's surroundings or the sun, and to test for preferred-frame effects that would precess the electrons about a direction fixed in inertial space. We find $|g_{\rm P}^e g_{\rm S}^N|/(\hbar c)< 1.7 \times 10^{-36}$ and $|g_{\rm A}^e g_{\rm V}^N|/(\hbar c) < 4.8 \times 10^{-56}$ for $\lambda > 1$AU. Our preferred-frame constraints, interpreted in the Kosteleck\'y framework, set an upper limit on the parameter $|\bm{\tilde {b}}^e| \leq 5.0 \times 10^{-21}$ eV that should be compared to the benchmark value $m_e^2/M_{\rm Planck}= 2 \times 10^{-17}$ eV.Comment: 4 figures, accepted for publication in Physical Review Letter

Aeroelastic model helicopter rotor testing in the Langley TDT

Wind-tunnel testing of a properly scaled aeroelastic model helicopter rotor is considered a necessary phase in the design development of new or existing rotor systems. For this reason, extensive testing of aeroelastically scaled model rotors is done in the Transonic Dynamics Tunnel (TDT) located at the NASA Langley Research Center. A unique capability of this facility, which enables proper dynamic scaling, is the use of Freon as a test medium. A description of the TDT and a discussion of the benefits of using Freon as a test medium are presented. A description of the model test bed used, the Aeroelastic Rotor Experimental System (ARES), is also provided and examples of recent rotor tests are cited to illustrate the advantages and capabilities of aeroelastic model rotor testing in the TDT. The importance of proper dynamic scaling in identifying and solving rotorcraft aeroelastic problems, and the importance of aeroelastic testing of model rotor systems in the design of advanced rotor systems are demonstrated

A Systematic Review and Meta-Analysis Estimating the Expected Dropout Rates in Randomized Controlled Trials on Yoga Interventions

© 2016 Holger Cramer et al. A reasonable estimation of expected dropout rates is vital for adequate sample size calculations in randomized controlled trials (RCTs). Underestimating expected dropouts rates increases the risk of false negative results while overestimating rates results in overly large sample sizes, raising both ethical and economic issues. To estimate expected dropout rates in RCTs on yoga interventions, MEDLINE/PubMed, Scopus, IndMED, and the Cochrane Library were searched through February 2014; a total of 168 RCTs were meta-analyzed. Overall dropout rate was 11.42% (95% confidence interval [CI] = 10.11%, 12.73%) in the yoga groups; rates were comparable in usual care and psychological control groups and were slightly higher in exercise control groups (rate = 14.53%; 95% CI = 11.56%, 17.50%; odds ratio = 0.82; 95% CI = 0.68, 0.98; p = 0.03). For RCTs with durations above 12 weeks, dropout rates in yoga groups increased to 15.23% (95% CI = 11.79%, 18.68%). The upper border of 95% CIs for dropout rates commonly was below 20% regardless of study origin, health condition, gender, age groups, and intervention characteristics; however, it exceeded 40% for studies on HIV patients or heterogeneous age groups. In conclusion, dropout rates can be expected to be less than 15 to 20% for most RCTs on yoga interventions. Yet dropout rates beyond 40% are possible depending on the participants' sociodemographic and health condition

Mindfulness-based stress reduction for breast cancer- A systematic review and meta-analysis

Objective The aim of this systematic review and meta-analysis was to assess the effectiveness of mindfulness-based stress reduction (MBSR) and mindfulness-based cognitive therapy (MBCT) in patients with breast cancer. Methods The medline, Cochrane Library, embase, cambase, and PsycInfo databases were screened through November 2011. The search strategy combined keywords for MBSR and MBCT with keywords for breast cancer. Randomized controlled trials (RCTs) comparing MBSR or MBCT with control conditions in patients with breast cancer were included. Two authors independently used the Cochrane risk of bias tool to assess risk of bias in the selected studies. Study characteristics and outcomes were extracted by two authors independently. Primary outcome measures were health-related quality of life and psychological health. If at least two studies assessing an outcome were available, standardized mean differences (SMDS) and 95% confidence intervals (CIs) were calculated for that outcome. As a measure of heterogeneity, I 2 was calculated. Results Three RCTs with a total of 327 subjects were included. One RCT compared MBSR with usual care, one RCT compared MBSR with free-choice stress management, and a three-arm RCT compared MBSR with usual care and with nutrition education. Compared with usual care, MBSR was superior in decreasing depression (SMD: -0.37; 95% CI: -0.65 to -0.08; p = 0.01; I 2 = 0%) and anxiety (SMD: -0.51; 95% CI: -0.80 to -0.21; p = 0.0009; I 2 = 0%), but not in increasing spirituality (SMD: 0.27; 95% CI: -0.37 to 0.91; p = 0.41; I 2 = 79%). Conclusions There is some evidence for the effectiveness of MBSR in improving psychological health in breast cancer patients, but more RCTs are needed to underpin those results. © 2012 Multimed Inc