Bistable Helmholtz dark spatial optical solitons in materials with self-defocusing saturable nonlinearity

We present, to the best of our knowledge, the first exact dark spatial solitons of a nonlinear Helmholtz equation with a self-defocusing saturable refractive-index model. These solutions capture oblique (arbitrary-angle) propagation in both the forward and backward directions, and they can also exhibit a bistability characteristic. A detailed derivation is presented, obtained by combining coordinate transformations and direct-integration methods, and the corresponding solutions of paraxial theory are recovered asymptotically as a subset. Simulations examine the robustness of the new Helmholtz solitons, with stationary states emerging from a range of perturbed input beams

Body silhouettes as a tool to reflect obesity in the past

<div><p>Life course data on obesity may enrich the quality of epidemiologic studies analysing health consequences of obesity. However, achieving such data may require substantial resources.</p><p>We investigated the use of body silhouettes in adults as a tool to reflect obesity in the past. We used large population-based samples to analyse to what extent self-reported body silhouettes correlated with the previously measured (9–23 years) body mass index (BMI) from both measured (European Community Respiratory Health Survey, N = 3 041) and self-reported (Respiratory Health In Northern Europe study, N = 3 410) height and weight. We calculated Spearman correlation between BMI and body silhouettes and ROC-curve analyses for identifying obesity (BMI ≥30) at ages 30 and 45 years. Spearman correlations between measured BMI age 30 (±2y) or 45 (±2y) and body silhouettes in women and men were between 0.62–0.66 and correlations for self-reported BMI were between 0.58–0.70. The area under the curve for identification of obesity at age 30 using body silhouettes <i>vs</i> previously measured BMI at age 30 (±2y) was 0.92 (95% CI 0.87, 0.97) and 0.85 (95% CI 0.75, 0.95) in women and men, respectively; for previously self-reported BMI, 0.92 (95% CI 0.88, 0.95) and 0.90 (95% CI 0.85, 0.96). Our study suggests that body silhouettes are a useful epidemiological tool, enabling retrospective differentiation of obesity and non-obesity in adult women and men.</p></div

Agreement of cutpoints on activity intensity, minute by minute.

<p>Percent of time (total 14.7 hours / day, 8780 days).</p

Large differences in estimated activity intensity between uni- and triaxial accelerometric cutpoints originally calibrated to the same dataset.

<p>Romanzini’s uni- and triaxial cutpoints from Romanzini M; Petroski, EL; Ohara, D; Dourado, AC; Reichert, FF. Calibration of ActiGraph GT3X, Actical and RT3 accelerometers in adolescents. European Journal of Sport Science. 2014;14(1):91–9. doi: <a href="https://doi.org/10.1080/17461391.2012.732614" target="_blank">10.1080/17461391.2012.732614</a>.</p

Population characteristics.

<p>Mean (standard deviation) unless otherwise stated.</p

Engagement in Sports with 9 or Fewer Episodes for Both Sexes.

<p>Activity levels as described in[<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135630#pone.0135630.ref024" target="_blank">24</a>]. MVPA is moderate or vigorous. Moderate + vigorous may not sum to MVPA because of rounding. Team sport defined as any requiring interaction with other participants, in line with [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135630#pone.0135630.ref021" target="_blank">21</a>].</p><p>Engagement in Sports with 9 or Fewer Episodes for Both Sexes.</p

Mean difference (MD) of FEV1 in % predicted between study participants exposed to bg dust at the workplace and no/low exposed participants.

<p>Mean difference (MD) of FEV1 in % predicted between study participants exposed to bg dust at the workplace and no/low exposed participants.</p

Multivariable Predictors of MVPA in Sport, All Episodes.

<p>¹⁾ Binary: 1 if better-educated parent entered college, 0 if not.</p><p>²⁾ Activity levels as described in [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135630#pone.0135630.ref024" target="_blank">24</a>]. MVPA is moderate or vigorous physical activity and refers to non-sporting days only. Participants with sport every day (9, 1.4%) are missing.</p><p>³⁾ Team sport defined as any requiring interaction with other participants, in line with [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135630#pone.0135630.ref021" target="_blank">21</a>]</p><p>N/A = P ≥0.05 so predictor was removed from the model.,— = not included in initial model</p><p>Predictors above the double line (age, study center, parental education, and gender; episode length when predicting zero MVPA, but not when predicting nonzero MVPA) left in model regardless of statistical significance. Nonzero MVPA modeled with negative binomial regression with log of total sporting time as offset, zeroes with logistic regression, both with child as a repeated measure.</p><p>Multivariable Predictors of MVPA in Sport, All Episodes.</p

Engagement in Sports with 10 or More Episodes for at Least One Sex.

<p>Activity levels as described in[<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135630#pone.0135630.ref024" target="_blank">24</a>]. MVPA is moderate or vigorous. Moderate + vigorous may not sum to MVPA because of rounding. Team sport defined as any requiring interaction with other participants, in line with [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135630#pone.0135630.ref021" target="_blank">21</a>].</p><p>Engagement in Sports with 10 or More Episodes for at Least One Sex.</p

Standardized mean difference of the ratio FEV1/FVC between study participants exposed to bg dust at the work place and low/no exposed participants.

<p>Standardized mean difference of the ratio FEV1/FVC between study participants exposed to bg dust at the work place and low/no exposed participants.</p