A large body of research demonstrates positive impacts of the Coping Power Program as a preventive intervention for youth behavioral outcomes, but potential collateral effects for caregivers is less known. The current study examined whether the youth-focused Coping Power Program can have a secondary impact on caregiver self-reported symptoms of depression and in turn result in longer-term impacts on child disruptive behavior problems including aggression, conduct problems and hyperactivity. Data from 360 youth/caregiver pairs across 8 waves of data (grades 4 through 10) were analyzed. We used two methodological approaches to (a) assess indirect effects in the presence of potential bidirectionality using timepoint-to-timepoint dynamic effects under Autoregressive Latent Trajectory modeling and (b) estimate scale scores in the presence of measurement non-invariance. Results showed that individually delivered Coping Power (ICP) produced greater direct effects on conduct problems and indirect effects on general externalizing and hyperactivity (through reductions in caregiver self-reported symptoms of depression), compared to group Coping Power (GCP). In comparison to GCP, ICP produced similar direct effects on reductions in caregiver depression. Child-focused prevention interventions can have an indirect impact on caregiver depression, which later shows improvements in longer-term reductions for child disruptive problems.

Dr Bradshaw and Professor Bateson reply: We replayed slowly the video of the hounds catching up with the stag which fell during a hunt on 29 August 1995. After many viewings we were convinced that the hounds did bite the stag, although we have stated repeatedly that the control of hounds is generally impressive. Since we submitted our paper to Animal Welfare, a much clearer case of hounds biting a stag has been videoed. This was at Marsh Bridge on 3 April 1999. We doubt very much if this case can be denied or explained away. We do not think this matter of biting is central in the debate about the welfare of the hunted deer, but if it is to be settled, both videos should be analysed by independent experts nominated by the stag-hunts and ourselves.

In southwestern England, red deer, Cervus elaphus, are culled by rifle (‘stalking’) or by hunting with hounds (‘hunting’). We compare the welfare costs of the two culling methods. Observations of hunts revealed that likely stressors such as close proximity to humans and hounds, active pursuit, noise, obstruction and physical restraint prior to despatch were very common. Other stressors, such as wounding, were rare. The blood profiles of hunted deer were compared both with injured deer, which were put down because they were thought to be suffering, and with stags stalked in the rutting season, when mature males rapidly lose weight and may be damaged in fights. Extensively hunted deer did not differ from severely injured deer in measures of muscle disruption: in hunted deer measures of red blood cell damage and psychological stress were higher. Hunted stags killed during the rut showed markedly higher levels of measures of blood and muscle cell disruption, psychological stress and fat reserve mobilization than stalked stags killed during this season. Estimates of wounding rates by stalkers showed that 11 per cent of deer required two or more shots to kill, 7 per cent took 2—15 min to die and 2 per cent escaped wounded. Overall, we judged that the welfare costs associated with hunting red deer were higher than those associated with stalking, and reducing the welfare costs associated with hunting was much less feasible than reducing those associated with stalking.

OBJECTIVES/GOALS: The overarching objective is to assess the value of promoting team science practices across a diverse clinical translational science community through the development of learning modules. We aim to share lessons learned to help inform best practices for CTSA hubs interested in promoting team science. METHODS/STUDY POPULATION: We recently created a series of self-paced learning modules focused on the science of team science, which include a variety of text and multimedia content. A preliminary assessment was conducted to determine the perceived value of six video team science Learning Shots and to identify areas for improvement. Significant content revisions are underway based on respondent feedback. In early 2022, a follow up survey will solicit feedback from a larger sample of researchers to reassess the learning modules and to ensure that desired improvements were achieved. We will incorporate continuous improvement cycles to gather future feedback, track improvements, and identify potential future direction for new content. RESULTS/ANTICIPATED RESULTS: The preliminary assessment identified the most effective aspects of the modules to be the variety and knowledge of speakers, diversity of topics, organization of the content, and appropriateness of length. Least effective aspects included a desire for more information in some content areas and not enough focus on the challenges of team science for junior faculty. Suggested areas for improvement include a desire for supplemental descriptive text, links to tools that enable teams to be productive, and additional examples from researchers. The follow up study is expected to yield more detailed information on the impacts of the improvements and the overall effectiveness of the modules. DISCUSSION/SIGNIFICANCE: This project provides insights for CTSA Hubs interested in promoting team science and best practices when developing learning modules. Results contribute to what is known about researchers interest in learning about team science and the effectiveness of using online formats for delivery.

The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.

Building on prior work regarding the potential for peer contagion or deviance training in group delivered interventions (Dishion & Dodge, 2005, 2006; Dodge, Dishion, & Lansford, 2006), we leveraged data from a randomized trial, testing the integration of two preventive interventions (Promoting Alternative THinking Strategies and PAX Good Behavior Game), to explore the extent to which classroom contextual factors served as either a barrier to or a motivator for teachers to implement the evidence-based PAX Good Behavior Game with high frequency or dosage. We included students’ baseline levels of behavior, measured with regard to both positive (i.e., engagement and social emotional skills) and negative (i.e., hyperactive and aggressive-disruptive) behaviors. Data were collected from 204 teachers in 18 urban elementary schools. A series of multilevel structural equation models were fit to the data. The analyses indicated that classrooms with higher classroom levels of aggressive behavior, on average, at baseline had teachers with lower implementation dosage (i.e., played fewer games) across the school year. In addition, teachers who reported higher baseline levels of emotional exhaustion, regardless of student behavior, also reported lower implementation dosage. Taken together, the results indicated that negative, but not positive, contextual factors at baseline were related to lower implementation dosage; this, in turn, suggests that negative contextual factors may serve as a barrier, rather than a motivator, of teachers’ implementation dosage of classroom-based preventive interventions.

In this lecture I hope to bring together the two branches of turbulence studies, (1) the fundamental study of the physics and mathematics of turbulent flow and (2) the methods of calculating turbulent flow development which are used by aircraft designers and other fluid dynamicists. While it is entirely reasonable that aircraft designers should wish to predict the behaviour of turbulent boundary layers without going deeply into the physical processes which govern their development, it is by no means reasonable that those who develop calculation methods in the first place should ignore the physics of the flow, or represent it by simple-minded formulae chosen for mathematical convenience rather than physical plausibility. Turbulence is not a simple phenomenon! The more naive integral methods that were in vogue until a few years ago have been disposed of once and for all by Thompson. The only method that emerged from Thompson’s review with any credit was Head’s entrainment method, which was distinguished from most of the other integral methods by being based on a clear physical hypothesis about turbulent flow. Head himself regarded this hypothesis as a very crude attempt to represent the entrainment properties of the turbulence, and indeed it is easy to see that this sort of hypothesis must fail in some of the more difficult situations.

Identification of priority populations such as men who have sex with men (MSM) is important in surveillance systems to monitor trends of sexually transmitted infections (STIs). We explored using routinely collected non-behavioural data as a means to establish MSM status in surveillance by assessing anorectal swab as a marker of male-to-male sexual exposure. We used chlamydia testing data from a sexual health clinic, 2007–2012. Men reporting any male sexual partner(s) in the previous 12 months were considered MSM. The dataset was split into development and validation samples to develop a univariate predictive model and assess the model fit. The dataset included 30 358 individual men and 48 554 episodes of STI testing; 45% were among reported MSM and an anorectal swab was performed in 40% of testing episodes. Anorectal swabbing had good diagnostic performance as a marker for MSM status (sensitivity = 87%, specificity = 99%, positive predictive value = 98·6%, negative predictive value = 90·3%). The model showed good fit against the internal validation sample (area under the curve = 0·93). Anorectal swabs are a valid marker of MSM behaviour in surveillance data from sexual health clinics, and they are likely to be particularly useful for monitoring STI trends among MSM with higher risk behaviour.

Several workers have found evidence for the presence of longitudinal vortices in wind tunnel wall boundary layers near the centre line of each wall, although the only actual publication appears to be the reproduction of Bearman's work in Ref. 3. The phenomenon usually observed is shown in Fig. 1: the boundary layer is considerably thickened near the centre line. (This symmetrical and localised perturbation should be distinguished from the effect of non-uniformities in the wind tunnel screens which apparently also leads to longitudinal vortices, randomly spaced across the width of the working section). The hypothetical vortex pattern is also shown in Fig. 1: it arises because lateral pressure gradients in the wind tunnel contraction naturally deflect the slow-moving fluid in the boundary layer towards the centre line more strongly than the main ‘inviscid’ part of the flow, implying the generation of longitudinal vorticity: this is secondary flow of Prandtl's first kind.

In recent years, manufacturers of centrifugal blowers for ventilation systems have abandoned the traditional arrangement of radial vanes shown in Fig. 1(a) for the “backward-aerofoil” arrangement shown in Fig. 1(b), which is the same as a conventional centrifugal water pump. Unlike the older type, the aerofoil-type blower does not depend on “centrifugal force” to produce a pressure rise despite the misleading accounts given in some hydraulics textbooks (the circumferential component of the air velocity is zero at entry and small at exit) although it does depend on the increase in blade peripheral velocity from the entry to the exit (which explains the curious blade arrangement).

A simplified analysis indicates that the increase in profile drag of an aerofoil due to an isolated roughness element is, in general, different from the drag of the element measured on a flat plate with the same free-stream velocity. This “magnification” effect is caused chiefly by the effect of the pressure gradients on the boundary layer downstream of the roughness element.

The degree of magnification is not closely approximated by the ratio of local to free-stream dynamic pressure and, in many typical cases, the contribution to the drag due to roughness elements may be seriously under-estimated in this way.

Measurements of the effect of the initial boundary-layer thickness on the subsequent development of a turbulent boundary-layer in an adverse pressure gradient support the theoretical conclusions.

Existing approximate formulae for the thickness of laminar and turbulent boundary layers are used to derive a method of calculating the free-stream velocity distribution corresponding to a given variation of shape parameter.

Thwaites has given the formula

for the momentum thickness of a laminar boundary layer with free-stream velocity u (x). This is the integral form of the empirical equation

It was easy for me to choose a subject for this lecture. First, turbulence is an important part of engineering fluid dynamics which has not so far been treated in the Reynolds-Prandtl lectures; secondly, it is the most obvious link between the careers of our two heroes; and thirdly it is the only scientific subject on which I am even remotely qualified to lecture before such a distinguished audience. The first and second propositions are sufficiently demonstrated by the annual consumption of something of the order of 1010kg of kerosene to overcome the effects of Reynolds’ stresses in Prandtl’s boundary layers. Have any two human beings ever had such a spectacular memorial? (Yes, Lanchester and Prandtl, to whose induced drag we sacrifice another 1010kg of fuel each year.)

Morgan has described a spatial instability in the flow through screens or grids of small open-area ratio. Head and Rechenberg and others have observed large span-wise variations in the thickness and shear stress of nominally two-dimensional boundary layers on flat plates and aerofoils in wind tunnels. It now appears that these spanwise variations are caused by the instability of flow through the screens. The jets of air issuing from the pores of the screen attempt to entrain more air by the usual mixing processes, but can only entrain it from each other, so that groups of jets coalesce in rather random (steady) patterns determined by small irregularities in the weave. The resulting variations in axial velocity are virtually eliminated by the wind tunnel contraction, but variations in flow direction are not so greatly reduced: a theoretical analysis shows that the observed variations of boundary-layer thickness, which often reach ± 10 per cent of the mean, can be produced by directional variations in the working section of the order of ± 1/20 deg, with a spanwise wavelength of the same order as the boundary-layer thickness.

Even with today’s computers, a wind tunnel is an essential tool in engineering, both for model tests and basic research. Since the 1930s, when the strong effect of free-stream turbulence on shear layers became apparent, emphasis has been laid on wind tunnels with low levels of turbulence and unsteadiness. Consequently most high performance wind tunnels were designed as closed-circuit types (Fig. 1(a)) to ensure a controlled return flow. However, as will be seen below, it is possible with care to achieve high performance from an open-circuit tunnel, thus saving space and construction cost. ‘Blower’ tunnels (with the fan at entry to the tunnel, Fig. 1(b)) facilitate large changes in working section arrangements; to cope with the resulting large changes in operating conditions, a centrifugal fan is preferable to an axial one. For ease of changing working sections the exit diffuser is often omitted from small blower tunnels, at the cost of a power factor greater than unity. This paper concentrates on the design of small blower tunnels but most of the information is applicable to wind tunnels in general.