The structure of gravel-bed flow with intermediate submergence: a laboratory study

The paper reports an experimental study of the flow structure over an immobile gravel bed in open channel at intermediate submergence, with particular focus on the near-bed region. The experiments consisted of velocity measurements using three-component (stereoscopic) Particle Image Velocimetry (PIV) in near-bed horizontal plane and two-component PIV in three vertical planes that covered three distinctly different hydraulic scenarios where the ratio of flow depth to roughness height (i.e., relative submergence) changes from 7.5 to 10.8. Detailed velocity measurements were supplemented with fine-scale bed elevation data obtained with a laser scanner. The data revealed longitudinal low-momentum and high-momentum "strips'' in the time-averaged velocity field, likely induced by secondary currents. This depth-scale pattern was superimposed with particle-scale patches of flow heterogeneity induced by gravel particle protrusions. A similar picture emerged when considering second-order velocity moments. The interaction between the flow field and gravel-bed protrusions is assessed using cross correlations of velocity components and bed elevations in a horizontal plane just above gravel particle crests. The cross correlations suggest that upward and downward fluid motions are mainly associated with upstream-facing and lee sides of particles, respectively. Results also show that the relative submergence affects the turbulence intensity profiles for vertical velocity over the whole flow depth, while only a weak effect, limited to the near-bed region, is noticed for streamwise velocity component. The approximation of mean velocity profiles with a logarithmic formula reveals that log-profile parameters depend on relative submergence, highlighting inapplicability of a conventional "universal'' logarithmic law for gravel-bed flows with intermediate submergence

Adaptive Mobile Health Intervention for Adolescents with Asthma: Iterative User-Centered Development

Background: Adolescents diagnosed with persistent asthma commonly take less than 50% of their prescribed inhaled corticosteroids (ICS), placing them at risk for asthma-related morbidity. Adolescents’ difficulties with adherence occur in the context of normative developmental changes (eg, increased responsibility for disease management) and rely upon still developing self-regulation and problem-solving skills that are integral for asthma self-management. We developed an adaptive mobile health system, Responsive Asthma Care for Teens (ReACT), that facilitates self-regulation and problem-solving skills during times when adolescents’ objectively measured ICS adherence data indicate suboptimal rates of medication use. Objective: The current paper describes our user-centered and evidence-based design process in developing ReACT. We explain how we leveraged a combination of individual interviews, national crowdsourced feedback, and an advisory board comprised of target users to develop the intervention content. Methods: We developed ReACT over a 15-month period using one-on-one interviews with target ReACT users (n=20), national crowdsourcing (n=257), and an advisory board (n=4) to refine content. Participants included 13-17–year-olds with asthma and their caregivers. A total of 280 adolescents and their caregivers participated in at least one stage of ReACT development. Results: Consistent with self-regulation theory, adolescents identified a variety of salient intrapersonal (eg, forgetfulness, mood) and external (eg, changes in routine) barriers to ICS use during individual interviews. Adolescents viewed the majority of ReACT intervention content (514/555 messages, 93%) favorably during the crowdsourcing phase, and the advisory board helped to refine the content that did not receive favorable feedback during crowdsourcing. Additionally, the advisory board provided suggestions for improving additional components of ReACT (eg, videos, message flow). Conclusions: ReACT involved stakeholders via qualitative approaches and crowdsourcing throughout the creation and refinement of intervention content. The feedback we received from participants largely supported ReACT’s emphasis on providing adaptive and personalized intervention content to facilitate self-regulation and problem-solving skills, and the research team successfully completed the recommended refinements to the intervention content during the iterative development process

Large-eddy simulation of two-dimensional dunes in a steady, unidirectional flow

We performed large-eddy simulations of the flow over a typical two-dimensional dune geometry at laboratory scale (the Reynolds number based on the average channel height andmean velocity is 18,900) using the Lagrangian dynamic eddy-viscosity subgrid-scale model. The results are validated by comparison with simulations and experiments in the literature. The flowseparates at the dune crest, generating a shear layer that plays a crucial role in the transport of momentum and energy, and the generation of coherent structures. The turbulent kinetic energy budgets show the importance of the turbulent transport and mean-flow advection in the bulk flow above the shear layer. In the recirculation zone and in the attached boundary layers production and dissipation are the most important terms. Large, coherent structures of various types can be observed. Spanwise vortices are generated in the separated shear layer due to the Kelvin-Helmholtz instability; as they are advected, they undergo lateral instabilities and develop into horseshoe-like structures, are tilted downward, and finally reach the surface. The ejection that occurs between the legs of the vortex creates the upwelling and downdrafting events on the free surface known as "boils." Near-wall turbulence, after the reattachment point, is affected by large streamwise Taylor-Görtler vortices generated on the concave part of the stoss side, which affect the distribution of the near-wall streaks

Responsive Asthma Care for Teens (ReACT): Development protocol for an adaptive mobile health intervention for adolescents with asthma

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.Introduction Asthma is a leading cause of youth morbidity in the USA, affecting >8% of youth. Adherence to inhaled corticosteroids (ICS) can prevent asthma-related morbidity; however, the typical adolescent with asthma takes fewer than 50% of their prescribed doses. Adolescents are uniquely vulnerable to suboptimal asthma self-management due to still-developing executive functioning capabilities that may impede consistent self-regulation and weaken attempts to use problem solving to overcome barriers to ICS adherence. Methods and analysis The aims of this project are to improve adherence to ICS as an important step towards better self-management among adolescents aged 13–17 years diagnosed with asthma by merging the efficacious behaviour change strategies found in behavioural health interventions with scalable, adaptive mobile health (mHealth) technologies to create the Responsive Asthma Care for Teens programme (ReACT). ReACT intervention content will be developed through an iterative user-centred design process that includes conducting (1) one-on-one interviews with 20 teens with asthma; (2) crowdsourced feedback from a nationally representative panel of 100 adolescents with asthma and (3) an advisory board of youth with asthma, a paediatric pulmonologist and a behavioural health expert. In tandem, we will work with an existing technology vendor to programme ReACT algorithms to allow for tailored intervention delivery. We will conduct usability testing of an alpha version of ReACT with a sample of 20 target users to assess acceptability and usability of our mHealth intervention. Participants will complete a 4-week run-in period to monitor their adherence with all ReACT features turned off. Subsequently, participants will complete a 4-week intervention period with all ReACT features activated. The study started in October 2018 and is scheduled to conclude in late 2019. Ethics and dissemination Institutional review board approval was obtained at the University of Kansas and the University of Florida. We will submit study findings for presentation at national research conferences that are well attended by a mix of psychologists, allied health professionals and physicians. We will publish study findings in peer-reviewed journals read by members of the psychology, nursing and pulmonary communities

Turbulence structure and momentum exchange in compound channel flows with shore ice covered on the floodplains

YesIce cover formed on a river surface is a common natural phenomenon during winter season in cold high latitude northern regions. For the ice-covered river with compound cross-section, the interaction of the turbulence caused by the ice cover and the channel bed bottom affects the transverse mass and momentum exchange between the main channel and floodplains. In this study, laboratory experiments are performed to investigate the turbulent flow of a compound channel with shore ice covered on the floodplains. Results show that the shore ice resistance restricts the development of the water flow and creates a relatively strong shear layer near the edge of the ice-covered floodplain. The mean streamwise velocity in the main channel and on the ice-covered floodplains shows an opposite variation pattern along with the longitudinal distance and finally reaches the longitudinal uniformity. The mixing layer bounded by the velocity inflection point consists of two layers that evolve downstream to their respective fully developed states. The velocity inflection point and strong transverse shear near the interface in the fully developed profile generate the Kelvin-Helmholtz instability and horizontal coherent vortices. These coherent vortices induce quasi-periodic velocity oscillations, while the dominant frequency of the vortical energy is determined through the power spectral analysis. Subsequently, quadrant analysis is used in ascertaining the mechanism for the lateral momentum exchange, which exhibits the governing contributions of sweeps and ejections within the vortex center. Finally, an eddy viscosity model is presented to investigate the transverse momentum exchange. The presented model is well validated through comparison with measurements, whereas the constants α and β appeared in the model need to be further investigated.National Natural Science Foundation of China (NSFC). Grant Numbers: 52020105006, 11872285: State Key Laboratory of Water Resources and Hydropower Engineering Science (WRHES), Wuhan University. Grant Number: 2018HLG0

A five-sample confirmatory factor analytic study of burnout-depression overlap

Objective: It has been asserted that burnout—a condition ascribed to unresolvable job stress—should not be mistaken for a depressive syndrome. In this confirmatory factor analytic study, the validity of this assertion was examined. Methods: Five samples of employed individuals, recruited in Switzerland and France, were mobilized for this study (N = 3,113). Burnout symptoms were assessed with the Shirom–Melamed Burnout Measure, the Maslach Burnout Inventory (MBI)—General Survey, and the MBI for Educators. Depressive symptoms were measured with the PHQ‐9. Results: In all five samples, the latent factors pertaining to burnout’s components correlated on average more highly with the latent Depression factor than with each other, even with fatigue‐related items removed from the PHQ‐9. Second‐order factor analyses indicated that the latent Depression factor and the latent factors pertaining to burnout’s components were reflective of the same overarching factor. Conclusions: This study suggests that the burnout-depression distinction is artificial

Improvement of a System for Catchment, Pretreatment and Treatment of Runoff Water Using PIV Tests and Numerical Simulation

This paper studies how to improve the efficiency of a new system for catchment, pretreatment, and treatment of runoff water (SCPT). This system is integrated into an urban sustainable gravity settler that can decrease diffusive pollution. This study provides important advantages for the ecosystem by improving new sustainable drainage to clean runoff water. In this paper, an investigation methodology known as hybrid engineering (HE) was used. HE combines experimental tests and numerical simulations, both of them conducted on a 1:4-scale prototype. In this study, numerical simulations by the finite-volume method (FVM) and experimental tests by particle image velocimetry (PIV) were compared. A strong correlation between the numerical and experimental analysis was found. Next, the efficiency of the SCPTwas optimized by design of experiments (DOE). Analysis of experimental and numerical results and their comparison are presented in this paper.The authors wish to express their gratitude to the Spanish Ministry of Economy and Competitiveness for the research project BIA2009-08272 funding

Measurement of inositol 1,4,5-trisphosphate in living cells using an improved set of resonance energy transfer-based biosensors

Improved versions of inositol-1,4,5-trisphosphate (InsP3) sensors were created to follow intracellular InsP3 changes in single living cells and in cell populations. Similar to previous InsP3 sensors the new sensors are based on the ligand binding domain of the human type-I InsP3 receptor (InsP3R-LBD), but contain a mutation of either R265K or R269K to lower their InsP3 binding affinity. Tagging the InsP3R-LBD with N-terminal Cerulean and C-terminal Venus allowed measurement of Ins P3 in single-cell FRET experiments. Replacing Cerulean with a Luciferase enzyme allowed experiments in multi-cell format by measuring the change in the BRET signal upon stimulation. These sensors faithfully followed the agonist-induced increase in InsP3 concentration in HEK 293T cells expressing the Gq-coupled AT1 angiotensin receptor detecting a response to agonist concentration as low as 10 pmol/L. Compared to the wild type InsP3 sensor, the mutant sensors showed an improved off-rate, enabling a more rapid and complete return of the signal to the resting value of InsP3 after termination of M3 muscarinic receptor stimulation by atropine. For parallel measurements of intracellular InsP3 and Ca2+ levels in BRET experiments, the Cameleon D3 Ca2+ sensor was modified by replacing its CFP with luciferase. In these experiments depletion of plasma membrane PtdIns(4,5)P2 resulted in the fall of InsP3 level, followed by the decrease of the Ca2+-signal evoked by the stimulation of the AT1 receptor. In contrast, when type-III PI 4-kinases were inhibited with a high concentration of wortmannin or a more specific inhibitor, A1, the decrease of the Ca2+-signal preceded the fall of InsP3 level indicating an InsP3-, independent, direct regulation of capacitative Ca2+ influx by plasma membrane inositol lipids. Taken together, our results indicate that the improved InsP3 sensor can be used to monitor both the increase and decrease of InsP3 levels in live cells suitable for high-throughput BRET applications. © 2015, Public Library of Science. All rights reserved

Process evaluation for complex interventions in primary care: understanding trials using the normalization process model

Background: the Normalization Process Model is a conceptual tool intended to assist in understanding the factors that affect implementation processes in clinical trials and other evaluations of complex interventions. It focuses on the ways that the implementation of complex interventions is shaped by problems of workability and integration.Method: in this paper the model is applied to two different complex trials: (i) the delivery of problem solving therapies for psychosocial distress, and (ii) the delivery of nurse-led clinics for heart failure treatment in primary care.Results: application of the model shows how process evaluations need to focus on more than the immediate contexts in which trial outcomes are generated. Problems relating to intervention workability and integration also need to be understood. The model may be used effectively to explain the implementation process in trials of complex interventions.Conclusion: the model invites evaluators to attend equally to considering how a complex intervention interacts with existing patterns of service organization, professional practice, and professional-patient interaction. The justification for this may be found in the abundance of reports of clinical effectiveness for interventions that have little hope of being implemented in real healthcare setting

A migraine variant with abdominal colic and Alice in wonderland syndrome: a case report and review

<p>Abstract</p> <p>Background</p> <p>Abdominal migraine is a commonly described migraine variant in children and young adults, but associations with Alice in Wonderland syndrome and lilliputian hallucinations are exceptional.</p> <p>Case presentation</p> <p>A 20 years-old male experienced frequent and prolonged attacks of abdominal colic associated with autonomic manifestations started at the age of ten. At the age of 17, he additionally described prolonged attacks (≥ 7 days) of distortions of shape, size or position of objects or subjects. He said "Quite suddenly, objects appear small and distant (teliopsia) or large and close (peliopsia). I feel as I am getting shorter and smaller "shrinking" and also the size of persons are not longer than my index finger (a lilliputian proportion). Sometimes I see the blind in the window or the television getting up and down, or my leg or arm is swinging. I may hear the voices of people quite loud and close or faint and far. Occasionally, I experience attacks of migrainous headache associated with eye redness, flashes of lights and a feeling of giddiness. I am always conscious to the intangible changes in myself and my environment". There is a strong family history of common migraine. Clinical examination, brain-MRI and EEG were normal. Transcranial magnetic stimulation and evoked potentials revealed enhanced cortical excitability in multiple brain regions. Treatment with valproate resulted in marked improvement of all clinical and neurophysiological abnormalities.</p> <p>Conclusions</p> <p>The association between the two migraine variants (abdominal migraine and Alice in Wonderland Syndrome) might have clinical, pathophysiological and management implications. I think this is the first description in the literature.</p