Lagrangian measurements of turbulent dissipation over a shallow tidal flat from pulse coherent Acoustic Doppler Profilers

We present high resolution (25 mm spatial, 8 Hz temporal) profiles of velocity measured over a shallow tidal flat using pulse-coherent Acoustic Doppler Profilers mounted on surface drifters. The use of Lagrangian measurements mitigated the problem of resolving velocity ambiguities, a problem which often limits the application of high-resolution pulse-coherent profilers. Turbulent dissipation rates were estimated from second-order structure functions of measured velocity. Drifters were advected towards, and subsequently trapped on, a convergent surface front which marked the edge of a freshwater plume. Measured dissipation rates increased as a drifter deployed within the plume approached the front. A drifter then propagated with and along the front as the fresh plume spread across the tidal flats. Near-surface turbulent dissipation measured at the front roughly matched a theoretical mean-shear-cubed relationship, whereas dissipation measured in the stratified plume behind the front was suppressed. After removal of estimates affected by surface waves, near-bed dissipation matched the velocity cubed relationship, although scatter was substantial. Dissipation rates appeared to be enhanced when the drifter propagated across small subtidal channels

A novel drifter designed for use with a mounted Acoustic Doppler Current Profiler in shallow environments

We present a novel design for a surface drifter, mounted with a pulse-coherent Acoustic Doppler Current Profiler (ADCP) for measuring near-surface (depths 0.18-1 m) flows. During repeated drifter deployments over the tidal flats of Skagit Bay, the mounted ADCP recorded high quality and high resolution profiles of velocity in depths as shallow as 0.4 m. Depth-dependent velocities revealed regions of vertically sheared currents and wave motions not resolved by surface drifters alone. Although the cost of ADCPs is substantial, the drifter bodies were low cost, robust, and of simple construction

The Measurement of Suicide Assessment and the Development of a Treatment Strategy for Elders: Durkheim an Approach

The purpose of this study was to develop and validate Durkheim Suicide Assessment (DSA).The DSA was designed to measure suicide risk among older adults. Despite a major influence of Durkheim' theory in understanding suicide, little effort has been made to apply such theory in gerontological practice. Data were drawn from a survey of 380 older adults over the age of 65. Principal component analysis was conducted with the 80 items of the original DSA, which yielded the 26 items of the DSA. Furthermore we performed explore factor analyses to assess the factor structures of the DSA. Internal consistency reliability was examined using Cronbach's alpha. The results show that the DSA is a psychometrically sound measurement. Health care professionals can use the DSA to assess suicide potential and develop an effective treatment strategy based on the type of suicide in which the elder has the highest probability of pursuing

PHOENIX: Public Health and Obesity in England – the New Infrastructure eXamined First interim report: the scoping review

The PHOENIX project aims to examine the impact of structural changes to the health and care system in England on the functioning of the public health system, and on the approaches taken to improving the public’s health. The scoping review has now been completed. During this phase we analysed: Department of Health policy documents (2010-2013), as well as responses to those documents from a range of stakeholders; data from 22 semi-structured interviews with key informants; and the oral and written evidence presented at the House of Commons Communities and Local Government Committee on the role of local authorities in health issues. We also gathered data from local authority (LA) and Health and Wellbeing Board (HWB) websites and other sources to start to develop a picture of how the new structures are developing, and to collate demographic and other data on local authorities. A number of important themes were identified and explored during this phase. In summary, some key points related to three themes - governance, relationships and new ways of working - were: The reforms have had a profound effect on leadership within the public health system. Whilst LAs are now the local leaders for public health, in a more fragmented system, leadership for public health appears to be more dispersed amongst a range of organisations and a range of people within the LA. At national level, the leadership role is complex and not yet developed (from a local perspective). Accountability mechanisms have changed dramatically within public health, and many people still seem to be unclear about them. Some performance management mechanisms have disappeared, and much accountability now appears to rely on transparency and the democratic accountability that this would (theoretically) enable. The extent to which ‘system leaders’ within PHE are able to influence local decisions and performance will depend on the strength of relationships principally between the LA and the local Public Health England centre. These relationships will take time to develop. Many people have faced new ways of working, in new settings, and with new relationships to build. Public health teams in LAs have faced the most profound of these changes, having gone from a position of ‘expert voice’ to a position where they must defend their opinions and activities in the context of competing demands and severely restricted resources. Public health staff may require new skills, and may need to seek new ‘allies’ to thrive in the new environment. HWBs could be crucial in bringing together a fragmented system and dispersed leadership. The next phase of data collection will begin in March with the initiation of case study work. National surveys will be conducted in June/July this year (2014), and at the same time the following year. In this work, we will further explore the following themes: relationships, governance, decision making, new ways of working, and opportunities and difficulties

Towards Autonomous Operation of Robonaut 2

The Robonaut 2 (R2) platform, as shown in Figure 1, was designed through a collaboration between NASA and General Motors to be a capable robotic assistant with the dexterity similar to a suited astronaut [1]. An R2 robot was sent to the International Space Station (ISS) in February 2011 and, in doing so, became the first humanoid robot in space. Its capabilities are presently being tested and expanded to increase its usefulness to the crew. Current work on R2 includes the addition of a mobility platform to allow the robot to complete tasks (such as cleaning, maintenance, or simple construction activities) both inside and outside of the ISS. To support these new activities, R2's software architecture is being developed to provide efficient ways of programming robust and autonomous behavior. In particular, a multi-tiered software architecture is proposed that combines principles of low-level feedback control with higher-level planners that accomplish behavioral goals at the task level given the run-time context, user constraints, the health of the system, and so on. The proposed architecture is shown in Figure 2. At the lowest-level, the resource level, there exists the various sensory and motor signals available to the system. The sensory signals for a robot such as R2 include multiple channels of force/torque data, joint or Cartesian positions calculated through the robot's proprioception, and signals derived from objects observable by its cameras

Prototyping 1,4-butanediol (BDO) biosynthesis pathway in a cell-free transcription-translation (TX-TL) system

Current methods for assembling metabolic pathways require a process of repeated trial and error and have a long design-build-test cycle. Further, it remains a challenge to precisely tune enzyme expression levels for maximizing target metabolite production. Recently it was shown that a cell-free transcriptional-translation system (TX-TL) can be used to rapidly prototype novel complex biocircuits as well as metabolic pathways. TX-TL systems allow protein expression from multiple DNA pieces, opening up the possibility of modulating concentrations of DNA encoding individual pathway enzymes and testing the related effect on metabolite production. In this work, we demonstrate TX-TL as a platform for exploring the design space of metabolic pathways using a 1,4-BDO biosynthesis pathway as an example. Using TX-TL, we verified enzyme expression and enzyme activity and identified the conversion of 4-hydroxybutyrate to downstream metabolites as a limiting step of the 1,4-BDO pathway. We further tested combinations of various enzyme expression levels and found increasing downstream enzyme expression levels improved 1,4-BDO production

Predictions and rewards affect decision-making but not subjective experience

To survive, organisms constantly make decisions to avoid danger and maximize rewards in information-rich environments. As a result, decisions about sensory input are not only driven by sensory information but also by other factors, such as the expected rewards of a decision (known as the payoff matrix) or by information about temporal regularities in the environment (known as cognitive priors or predictions). However, it is unknown to what extent these different types of information affect subjective experience or whether they merely result in nonperceptual response criterion shifts. To investigate this question, we used three carefully matched manipulations that typically result in behavioral shifts in decision criteria: a visual illusion (Müller-Lyer condition), a punishment scheme (payoff condition), and a change in the ratio of relevant stimuli (base rate condition). To gauge shifts in subjective experience, we introduce a task in which participants not only make decisions about what they have just seen but are also asked to reproduce their experience of a target stimulus. Using Bayesian ordinal modeling, we show that each of these three manipulations affects the decision criterion as intended but that the visual illusion uniquely affects sensory experience as measured by reproduction. In a series of follow-up experiments, we use computational modeling to show that although the visual illusion results in a distinct drift-diffusion (DDM) parameter profile relative to nonsensory manipulations, reliance on DDM parameter estimates alone is not sufficient to ascertain whether a given manipulation is perceptual or nonperceptual