Active8! Technology-based intervention to promote physical activity in hospital employees

Purpose: Increase physical activity in healthcare employees using health messaging, and compare email with mobile phone short-message service (SMS) as delivery channels. Design: Randomised controlled trial Setting: UK hospital workplace Subjects: 296 employees (19-67 years, 53% of study website visitors) Intervention: 12-week messaging intervention designed to increase physical activity and delivered via SMS (n=147) or email (n=149); content tailored using Theory of Planned Behaviour (TPB) and limited to 160 characters. Measures: Baseline, 6, 12 and 16 weeks. Online measures included TPB constructs; physical activity behaviour on the Global Physical Activity Questionnaire; health-related quality of life on the Short-Form 12. Analysis: General linear models for repeated measures. Results: Increase in duration (mean hours/day) of moderate work-related activity and moderate recreational activity from baseline to 16 weeks. Short-lived increase in frequency (days/week) of vigorous recreational activity from baseline to 6 weeks. Increase in duration and frequency of active travel from baseline to 16 weeks. Emails generated greater changes than SMS in active travel and moderate activity (work and recreational). Conclusion: Minimal physical activity promotion delivered by SMS or email can increase frequency and duration of active travel, and duration of moderate-intensity physical activity at work and for leisure, which is maintained up to one-month after messaging ends. Both channels were useful platforms for health communication; emails were particularly beneficial with hospital employees

Convergence and multiplicities for the Lempert function

Given a domain $\Omega \subset \mathbb C$, the Lempert function is a functional on the space Hol (\D,\Omega) of analytic disks with values in $\Omega$, depending on a set of poles in $\Omega$. We generalize its definition to the case where poles have multiplicities given by local indicators (in the sense of Rashkovskii's work) to obtain a function which still dominates the corresponding Green function, behaves relatively well under limits, and is monotonic with respect to the indicators. In particular, this is an improvement over the previous generalization used by the same authors to find an example of a set of poles in the bidisk so that the (usual) Green and Lempert functions differ.Comment: 24 pages; many typos corrected thanks to the referee of Arkiv for Matemati

A comparison of FreeSurfer-generated data with and without manual intervention

This paper examined whether FreeSurfer - generated data differed between a fully – automated, unedited pipeline and an edited pipeline that included the application of control points to correct errors in white matter segmentation. In a sample of 30 individuals, we compared the summary statistics of surface area, white matter volumes, and cortical thickness derived from edited and unedited datasets for the 34 regions of interest (ROIs) that FreeSurfer (FS) generates. To determine whether applying control points would alter the detection of significant differences between patient and typical groups, effect sizes between edited and unedited conditions in individuals with the genetic disorder, 22q11.2 deletion syndrome (22q11DS) were compared to neurotypical controls. Analyses were conducted with data that were generated from both a 1.5 tesla and a 3 tesla scanner. For 1.5 tesla data, mean area, volume, and thickness measures did not differ significantly between edited and unedited regions, with the exception of rostral anterior cingulate thickness, lateral orbitofrontal white matter, superior parietal white matter, and precentral gyral thickness. Results were similar for surface area and white matter volumes generated from the 3 tesla scanner. For cortical thickness measures however, seven edited ROI measures, primarily in frontal and temporal regions, differed significantly from their unedited counterparts, and three additional ROI measures approached significance. Mean effect sizes for edited ROIs did not differ from most unedited ROIs for either 1.5 or 3 tesla data. Taken together, these results suggest that although the application of control points may increase the validity of intensity normalization and, ultimately, segmentation, it may not affect the final, extracted metrics that FS generates. Potential exceptions to and limitations of these conclusions are discussed

Pluricomplex Green and Lempert functions for equally weighted poles

For $\Omega$ a domain in $\mathbb C^n$, the pluricomplex Green function with poles $a_1, ...,a_N \in \Omega$ is defined as $G(z):=\sup \{u(z): u\in PSH_-(\Omega), u(x)\le \log \|x-a_j\|+C_j \text{when} x \to a_j, j=1,...,N \}$. When there is only one pole, or two poles in the unit ball, it turns out to be equal to the Lempert function defined from analytic disks into $\Omega$ by $L_S (z) :=\inf \{\sum^N_{j=1}\nu_j\log|\zeta_j|: \exists \phi\in \mathcal {O}(\mathbb D,\Omega), \phi(0)=z, \phi(\zeta_j)=a_j, j=1,...,N \}$. It is known that we always have $L_S (z) \ge G_S(z)$. In the more general case where we allow weighted poles, there is a counterexample to equality due to Carlehed and Wiegerinck, with $\Omega$ equal to the bidisk. Here we exhibit a counterexample using only four distinct equally weighted poles in the bidisk. In order to do so, we first define a more general notion of Lempert function "with multiplicities", analogous to the generalized Green functions of Lelong and Rashkovskii, then we show how in some examples this can be realized as a limit of regular Lempert functions when the poles tend to each other. Finally, from an example where $L_S (z) > G_S(z)$ in the case of multiple poles, we deduce that distinct (but close enough) equally weighted poles will provide an example of the same inequality. Open questions are pointed out about the limits of Green and Lempert functions when poles tend to each other.Comment: 25 page

NextGen Flight Deck Data Comm: Auxiliary Synthetic Speech Phase I

Data Comm—a text-based controller-pilot communication system—is critical to many NextGen improvements. With Data Comm, communication becomes a visual task. Interacting with a visual Data Comm display may yield an unsafe increase in head-down time, particularly for single-pilot operations. This study examined the feasibility of supplementing Data Comm with synthetic speech. To this end, thirty-two pilots flew two experimental scenarios in a Cessna 172 Flight Training Device. In one scenario, ATC communication was with a text-only Data Comm display, in the other, communication was with a text Data Comm display with synthetic speech that read aloud each message (i.e., text+speech). Pilots heard traffic with similar call signs on the party line and received a conditional clearance (in both scenarios); in either scenario, pilots received a clearance that was countermanded by a live controller. Results indicated that relative to the text-only display, the text+speech display aided single-pilot performance by reducing head-down time, and may have prevented participants from acting early on the conditional clearance. Supplementing text Data Comm with speech did not introduce additional complications: participants were neither more likely to erroneously respond to similar call signs, nor to ignore a live ATC countermand

Performance of the Two Aerogel Cherenkov Detectors of the JLab Hall A Hadron Spectrometer

We report on the design and commissioning of two silica aerogel Cherenkov detectors with different refractive indices. In particular, extraordinary performance in terms of the number of detected photoelectrons was achieved through an appropriate choice of PMT type and reflector, along with some design considerations. After four years of operation, the number of detected photoelectrons was found to be noticeably reduced in both detectors as a result of contamination, yellowing, of the aerogel material. Along with the details of the set-up, we illustrate the characteristics of the detectors during different time periods and the probable causes of the contamination. In particular we show that the replacement of the contaminated aerogel and parts of the reflecting material has almost restored the initial performance of the detectors.Comment: 18 pages, 9 Figures, 4 Tables, 44 Reference