Airspace control plays an important role in the safety and fluidity of air traffic. A fundamental service for this purpose is audio communication through frequencies in the VHF bands. This paper describes the evaluation of the audio degradation of voice transmissions from control centre to the aircraft. The effects of more than one station broadcasting on the same frequency with carrier offset (climax mode) are analysed using perceptual evaluation of speech quality (PESQ) perceptual model. Comparative studies are performed to verify the degree of degradation of different audio transport systems and climax situation.

This study investigated the transactional relations between vocabulary and disruptive behaviors (DB; physical aggression and opposition/rule breaking/theft and vandalism), during the transition to formal schooling, using a community sample of 572 children. Cross-lagged panel model analyses were used to examine bidirectional relationships, comparing physical aggression to non-aggressive DB. Transactional associations between vocabulary and DB were observed, coinciding with school entry. Lower vocabulary in preschool (60mo.) was predictive of higher physical aggression scores in kindergarten. In turn, higher physical aggression in kindergarten was predictive of lower vocabulary in 1st grade. For non-aggressive DB, recurrent associations were found. Lower verbal skills in preschool (42mo.) and kindergarten predicted higher non-aggressive DB scores later in preschool and in 1st grade respectively. In turn, higher non-aggressive DB in kindergarten predicted lower vocabulary scores in 1st grade. In contrast to transactional paths from vocabulary to DB, transactional paths from DB to vocabulary observed after the transition to elementary school remained significant after controlling for comorbid hyperactivity, impulsivity and inattention behaviors, suggesting these links were specific to aggressive and non-aggressive DB. Practical implications for prevention are discussed.

In this work, nonlinear variational optimization is used for obtaining minimal seeds for the formation of turbulent bands in channel flow. Using nonlinear optimization together with energy bisection, we have found that the minimal energy threshold for obtaining spatially patterned turbulence scales with $Re^{-8.5}$ for $Re>1000$. The minimal seed, which is different to that found in a much smaller domain, is characterized by a spot-like structure surrounded by a low-amplitude large-scale quadrupolar flow filling the whole domain. This minimal-energy perturbation of the laminar flow has dominant wavelengths close to $4$ in the streamwise direction and $1$ in the spanwise direction, and is characterized by a spatial localization increasing with the Reynolds number. At $Re \lesssim 1200$, the minimal seed evolves in time, creating an isolated oblique band, whereas for $Re\gtrsim 1200$, a quasi-spanwise-symmetric evolution is observed, giving rise to two distinct bands. A similar evolution is found also at low $Re$ for non-minimal optimal perturbations. This highlights two different mechanisms of formation of turbulent bands in channel flow, depending on the Reynolds number and initial energy of the perturbation. The selection of one of these two mechanisms appears to be dependent on the probability of decay of the newly created stripe, which increases with time, but decreases with the Reynolds number.

Recently, many authors have investigated the origin and growth of turbulent bands in shear flows, highlighting the role of streaks and their inflectional instability in the process of band generation and sustainment. Recalling that streaks are created by an optimal transient growth mechanism, and motivated by the observation of a strong increase of the disturbance kinetic energy corresponding to the creation of turbulent bands, we use linear and nonlinear energy optimisations in a tilted domain to unveil the main mechanisms allowing the creation of a turbulent band in a channel flow. Linear transient growth analysis shows an optimal growth for wavenumbers having an angle of approximately $35^\circ$, close to the peak values of the premultiplied energy spectra of direct numerical simulations. This linear optimal perturbation generates oblique streaks, which, for a sufficiently large initial energy, induce turbulence in the whole domain, due to the lack of spatial localisation. However, spatially localised perturbations obtained by adding nonlinear effects to the optimisation or by artificially confining the linear optimal to a localised region in the transverse direction are characterised by a large-scale flow and lead to the generation of a localised turbulent band. These results suggest that two main elements are needed for inducing turbulent bands in a tilted domain: (i) a linear energy growth mechanism, such as the lift-up, for generating large-amplitude flow structures, which produce inflection points; (ii) spatial localisation, linked to the presence or generation of large-scale vortices. We show that these elements alone generate isolated turbulent bands also in large non-tilted domains.

This study examined whether the interaction between parenting and inhibitory control predicts hyperactivity-impulsivity and inattention in 195 children. Observation data of positive parenting were collected at 4 years, and mother reports of coercive parenting at 5 years, inhibitory control at 6 years, and hyperactivity-impulsivity/inattention at 7 years were obtained. The common and unique variance of hyperactivity-impulsivity and inattention symptoms were examined as outcomes using a bifactor model. Results indicated that positive parenting practices predicted lower levels of hyperactivity-impulsivity/inattention behaviors at age 7 only when children's inhibitory control was high. These results support the vantage sensitivity model, which posits that some individuals show an increased sensitivity to positive experiences exclusively, and support the appropriateness of a targeted prevention approach in early childhood.

Introduction: Needle-related procedures are considered the most important source of pain and distress in children in hospital settings. Time constraints, heavy workload, busy and noisy environment represent barriers to the use of available interventions for pain management during needle-related procedures. Therefore, the use of a rapid, easy-to-use intervention could improve procedural pain management practices. The objective was to determine if a device combining cold and vibration (Buzzy) is non-inferior (no worse) to a topical anesthetic (Maxilene) for pain management in children undergoing needle-related procedures in the Emergency Department (ED). Methods: This study was a randomized, controlled, non-inferiority trial. We enrolled children aged between 4-17 years presenting to the ED and requiring a needle-related procedure. Participants were randomly assigned to the Buzzy or Maxilene group. The primary outcome was the mean difference in pain intensity during the procedure, as measured with the CAS (0-10). Secondary outcomes were procedural distress, success of the procedure at first-attempt and satisfaction of parents. Results: A total of 352 participants were enrolled and 346 were randomized (Buzzy = 172; Maxilene = 174). Mean difference in procedural pain scores between groups was 0.64 (95%CI -0.1 to 1.3), showing that the Buzzy device was not non-inferior to Maxilene according to a non-inferiority margin of 0.70. No significant differences were observed for procedural distress (p = .370) and success of the procedure at first attempt (p = .602). Parents of both groups were very satisfied with both interventions (Buzzy = 7.8 ±2.66; Maxilene = 8.1 ±2.4), but there was no significant difference between groups (p = .236). Conclusion: Non-inferiority of the Buzzy device over a topical anesthetic was not demonstrated for pain management of children during a needle-related procedure in the ED. However, considering that topical anesthetics are underused in the ED setting and require time, the Buzzy device seems to be a promising alternative as it is a rapid, low-cost, easy-to-use and reusable intervention.

Introduction: The diagnosis of Salter-Harris Type 1 fractures in the Emergency Department (ED) is primarily clinical, as radiographs are usually unrevealing. We hypothesize that bilateral asymmetry of the growth plate, detected using bedside ultrasound (US), could improve the accuracy of this diagnosis in the ED. This study seeks to determine growth plate size according to age, and to establish normal variation in bilateral symmetry of growth plate cartilage, for the ulna, radius, tibia, and fibula, using bedside US in normal healthy children. Methods: This prospective observational study was conducted in a convenience sample of children ages 0-17 during planned visits to an elementary school, high school, and an outpatient pediatric clinic. A sample size of 177 was determined with a linear regression model using previously published data on the subject. The study was approved by the hospital and universitys ethics board. After a medical questionnaire with a research nurse, the participants underwent ultrasound evaluation of bilateral ulnae, radii, fibulae, and tibiae, to obtain still images of the physes from two orthogonal views. The evaluations were performed by 3 medical residents, 1 medical student, and by the supervising emergency physician. All ultrasonographers were EDE1 certified and specifically trained for growth plate imagery. The still images were evaluated ulteriorly and measurements taken of the physeal cartilage. Ten percent of the patients had their images re-evaluated by the supervising physician to determine inter-rater reliability. Results: A total of 227 patients were recruited. The median age was 8 years old with an interquartile range of (3;14). Mean growth plate size by age was determined, confirming decreasing growth plate size with advancing age for all articulations. The percentage of absolute difference between right and left, for all growth plates together, was a mean of 17% with a 95% CI of 16-19%. The overall inter-rater reliability was excellent at 0.84. Conclusion: This study establishes a reproducible technique of measuring growth plates with ultrasound. We suspect that increased asymmetry at the growth plate, beyond this established normal variation, may signify a physis widening or hematoma consistent with a Salter-Harris Type 1 fracture; this will be evaluated in a second study.

Introduction: When a female presents with abdominal pain and vaginal bleeding, a positive b-hcg level helps in the diagnosis of an ectopic pregnancy. A timely diagnosis as well as management is required for these cases. In many emergency departments, there can be delays in laboratory processing of quantitative b-hcg levels as well as qualitative urine pregnancy tests. In others, especially in rural hospitals in Canada, the laboratory closes at night and these tests cannot be processed until the morning. This may also help decrease length of stay for some patients in the emergency department. There are currently new point-of-care b-hcg tests on the market using capillary blood, but these are expensive and not readily available. The purpose of the study is to validate the most inexpensive point of care urine pregnancy tests readily available on the market for use with capillary blood samples. These point-of-care tests have only been studied with urine and whole blood. If validated with capillary blood, it would allow for a very practical, rapid, and inexpensive test which could help doctors and nurses to triage patients in a timely and more efficient fashion. Methods: In our emergency department, 385 patients between the ages of 18-50 with possible pregnancy, abdominal pain or vaginal bleeding will be included in the study. A capillary blood sample will be taken and applied to a cassette point-of-care pregnancy test with four drops of saline. Two independent investigators will assess the test. The results will be compared to a quantitative serum hCG assay and urine. If these tests are not done as part of the patients medical care, the patient will be contacted one month after to enquire if the patient is pregnant or not. The sensitivity, specificity, positive and negative predictive values will be calculated. Results: Data colleciton will begin in January 2018. Conclusion: No conclusions can yet be drawn.

The current investigation examined if changes in youth internalizing problems as a result of a family group cognitive behavioral (FGCB) preventive intervention for families with a parent with a history of depression had a cascade effect on youth social problems over 24 months and the bidirectional nature of these effects. One hundred eighty families with a parent with a history of major depressive disorder (M age = 41.96; 88.9% mothers) and a youth age 9 to 15 years (49.4% females; M age = 11.46) participated. Findings from a panel model indicated that, compared to a minimum intervention condition, the FGCB intervention significantly reduced youth internalizing problems at 12 months that in turn were associated with lower levels of social problems at 18 months. Similarly, the FGCB intervention reduced internalizing problems at 18 months, which were associated with fewer social problems at 24 months. Changes in social problems were not related to reductions in subsequent internalizing problems. The findings suggest that reductions in youth internalizing problems can lead to lower levels of social problems. Youth social problems are difficult to change; therefore, targeting internalizing problems may be an effective way to reduce the social problems of children of parents with a history of depression.

Epigenetics processes may play a vital role in the biological embedding of early environmental adversity and the development of psychopathology. Accumulating evidence suggests that maltreatment is linked to methylation of the glucocorticoid receptor gene, nuclear receptor subfamily 3, group C, member 1 (NR3C1), which is a key regulator of the hypothalamus–pituitary–adrenal axis. However, prior work has been exclusively cross-sectional, greatly constraining our understanding of stress-related epigenetic processes over time. In the current study, we examined the effect of maltreatment and other adversity on change in NR3C1 methylation among at-risk preschoolers to begin to characterize within-child epigenetic changes during this sensitive developmental period. Participants were 260 preschoolers (3–5 years old, 53.8% female), including 51.5% with moderate to severe maltreatment in the past 6 months. Child protection records, semistructured interviews, and parent reports were used to assess child stress exposure. Methylation of exons 1D and 1F of NR3C1 via saliva DNA were measured at two time points approximately 6 months apart. Results indicate that maltreated children evidence higher baseline levels of NR3C1 methylation, significant decreases in methylation over time, and then at follow-up, lower levels of methylation, relative to nonmaltreated preschoolers. Findings from the current study highlight the complex nature of stress-related epigenetic processes during early development.

While performing statistical–dynamical simulations for avalanche predetermination, a propagation model must reach a compromise between precise description of the avalanche flow and computation times. Crucial problems are the choice of appropriate distributions describing the variability of the different inputs/outputs and model identifiability. In this study, a depth-averaged propagation model is used within a hierarchical Bayesian framework. First, the joint posterior distribution is estimated using a sequential Metropolis–Hastings algorithm. Details for tuning the estimation algorithm are provided, as well as tests to check convergence. Of particular interest is the calibration of the two coefficients of a Voellmy friction law, with model identifiability ensured by prior information. Second, the point estimates are used to predict the joint distribution of different variables of interest for hazard mapping. Recent developments are employed to compute pressure distributions taking into account the rheology of snow. The different steps of the method are illustrated with a real case study, for which all possible decennial scenarios are simulated. It appears that the marginal distribution of impact pressures is strongly skewed, with possible high values for avalanches characterized by low Froude numbers. Model assumptions and results are discussed.