Assessment of a channel catfish population in a large open river system

Estimates of dynamic rate functions for riverine channel catfish, Ictalurus punctatus (Rafinesque), populations are limited. The open nature and inherent difficulty in sampling riverine environments and the propensity for dispersal of channel catfish impede estimation of population variables. However, contemporary population models (i.e. robust design models) can incorporate the open nature of these systems. The purpose of this study was to determine channel catfish population abundance, survival and size structure and to characterize growth in the lower Platte River, Nebraska, USA. Annual survival estimates of adult channel catfish were 13%–49%, and channel catfish abundance estimates ranged from 8,281 to 24,261 fish within a 10-km sampling reach. Channel catfish were predominantly (90%

Actuation and stiffening in fluid-driven soft robots using low-melting-point material

Soft material robots offer a number of advantages over traditional rigid robots in applications including humanrobot interaction, rehabilitation and surgery. These robots can navigate around obstacles, elongate, squeeze through narrow openings or be squeezed - and they are considered to be inherently safe. The ability to stiffen compliant soft actuators has been achieved by embedding various mechanisms that are generally decoupled from the actuation principle. Miniaturisation becomes challenging due to space limitations which can in turn result in diminution of stiffening effects. Here, we propose to hydraulically actuate soft manipulators with lowmelting- point material and, at the same time, be able to switch between a soft and stiff state. Instead of allocating an additional stiffening chamber within the soft robot, one chamber only is used for actuation and stiffening. Low Melting Point Alloy is integrated into the actuation chamber of a single-compartment soft robotic manipulator and the interfaced robotic syringe pump. Temperature change is enabled through embedded nichrome wires. Our experimental results show higher stiffness factors, from 9-12 opposing the motion of curvature, than those previously found for jamming mechanisms incorporated in separate additional chambers, in the range of 2-8 for the same motion

Continuous Uniform Finite Time Stabilization of Planar Controllable Systems

Continuous homogeneous controllers are utilized in a full state feedback setting for the uniform finite time stabilization of a perturbed double integrator in the presence of uniformly decaying piecewise continuous disturbances. Semiglobal strong $\mathcal{C}^1$ Lyapunov functions are identified to establish uniform asymptotic stability of the closed-loop planar system. Uniform finite time stability is then proved by extending the homogeneity principle of discontinuous systems to the continuous case with uniformly decaying piecewise continuous nonhomogeneous disturbances. A finite upper bound on the settling time is also computed. The results extend the existing literature on homogeneity and finite time stability by both presenting uniform finite time stabilization and dealing with a broader class of nonhomogeneous disturbances for planar controllable systems while also proposing a new class of homogeneous continuous controllers

Workplace violence in Queensland, Australia: the results of a comparative study

[Abstract]: This paper presents the results on workplace violence from a larger study undertaken in 2004. Comparison is made with the results of a similar study undertaken in 2001. The study involved the random sampling of 3000 nurses from the Queensland Nurses’ Union’s membership in the public (acute hospital and community nursing), private (acute hospital and domiciliary nursing) and aged care sectors (both public and private aged care facilities). The self-reported results suggest an increase in workplace violence in all three sectors. Whilst there are differences in the sources of workplace violence across the sectors, the major causes of workplace violence are: clients/patients, visitors/relatives, other nurses, nursing management and medical practitioners. Associations were also found between workplace violence and gender, the designation of the nurse, hours of employment, the age of the nurse, morale and perceptions of workplace safety. Whilst the majority of nurses reported that policies were in place for the management of workplace violence, these policies were not always adequate

Achieving provider engagement: providers' perceptions of implementing and delivering integrated care

The literature on integrated care is limited with respect to practical learning and experience. Although some attention has been paid to organizational processes and structures, not enough is paid to people, relationships, and the importance of these in bringing about integration. Little is known, for example, about provider engagement in the organizational change process, how to obtain and maintain it, and how it is demonstrated in the delivery of integrated care. Based on qualitative data from the evaluation of a large-scale integrated care initiative in London, United Kingdom, we explored the role of provider engagement in effective integration of services. Using thematic analysis, we identified an evolving engagement narrative with three distinct phases: enthusiasm, antipathy, and ambivalence, and argue that health care managers need to be aware of the impact of professional engagement to succeed in advancing the integrated care agenda

Is tagging with visual implant elastomer a reliable technique for marking earthworms?

Visual implant elastomer (VIE) has recently been employed to investigate different aspects of earthworm ecology. However, a number of fundamental questions relating to the detection and positioning of the tag, its persistence and potential effects on earthworms remain unknown. Seven earthworm species belonging to three ecological groupings, with different pigmentation and burrowing behaviour, were tagged using different coloured VIE. External inspection after two days, one week and 1, 10 and 27 months were followed by preservation, dissection and internal inspection. Tags could be seen in living specimens to 27 months, and dissection revealed that in most cases they were lodged in the coelomic cavity, held in place by septa. However, over longer time periods (more than two years), the chlorogogenous tissue tended to bind to the tags and made external observation increasingly difficult. Migration of the VIE material towards the posterior of the earthworm and potential loss of the tag were only observed on rare occasions, and a recovery rate in excess of 98% was recorded. By introducing a reasonable amount of VIE into segments, just after the clitellum, this technique can become a valuable tool in earthworm ecology and life history studies, particularly in short-medium term laboratory and field experiments

Digital storytelling and Co-creative Media: The role of community arts and media in propagating and coordinating population-wide creative practice

How is creative expression and communication extended among whole populations? What is the social and cultural value of this activity? What roles do formal agencies, community-based organisations and content producer networks play? Specifically, how do participatory media and arts projects and networks contribute to building this capacity in the contemporary communications environment

Ionic Tuning of Cobaltites at the Nanoscale

Control of materials through custom design of ionic distributions represents a powerful new approach to develop future technologies ranging from spintronic logic and memory devices to energy storage. Perovskites have shown particular promise for ionic devices due to their high ion mobility and sensitivity to chemical stoichiometry. In this work, we demonstrate a solid-state approach to control of ionic distributions in (La,Sr)CoO$_{3}$ thin films. Depositing a Gd capping layer on the perovskite film, oxygen is controllably extracted from the structure, up-to 0.5 O/u.c. throughout the entire 36 nm thickness. Commensurate with the oxygen extraction, the Co valence state and saturation magnetization show a smooth continuous variation. In contrast, magnetoresistance measurements show no-change in the magnetic anisotropy and a rapid increase in the resistivity over the same range of oxygen stoichiometry. These results suggest significant phase separation, with metallic ferromagnetic regions and oxygen-deficient, insulating, non-ferromagnetic regions, forming percolated networks. Indeed, X-ray diffraction identifies oxygen-vacancy ordering, including transformation to a brownmillerite crystal structure. The unexpected transformation to the brownmillerite phase at ambient temperature is further confirmed by high-resolution scanning transmission electron microscopy which shows significant structural - and correspondingly chemical - phase separation. This work demonstrates room-temperature ionic control of magnetism, electrical resistivity, and crystalline structure in a 36 nm thick film, presenting new opportunities for ionic devices that leverage multiple material functionalities

Functional and emotional outcomes after transient ischaemic attack: A 12-month prospective controlled cohort study

Background: Symptoms of transient ischemic attack are believed to fully resolve within 24 h of onset. Emerging evidence suggests that there may be prolonged functional and psychological impact, although studies have not been able to robustly identify whether these are the effect of transient ischemic attack or changes usually associated with ageing. We describe trajectories of disability and risk of anxiety and depression among patients seen at transient ischemic attack clinics over 12 months, compared to healthy controls. Methods: Thirty transient ischemic attack clinics across England participated. A total of 1320 participants were included: 373 diagnosed with transient ischemic attack, 186 with minor stroke, 310 with “possible transient ischemic attack,” 213 with another condition mimicking a transient ischemic attack and 238 controls recruited from primary care providers. Participants completed questionnaires after diagnosis then after 3, 6 and 12 months. Outcomes were the Nottingham Extended Activities of Daily Living Scale and the Hospital Anxiety and Depression Scale. Mixed effects regression was used to estimate group differences and trajectories. Results: At baseline, confirmed transient ischemic attack patients scored 1.31 HADS-Anxiety points (s.e. = 0.28; p < 0.001), 0.51 HADS-Depression points (s.e. = 0.26; p = 0.056), and 2.6 NEADL points (s.e. = 1.1; p = 0.020) worse than controls. At 12 months, the deficits were 0.78 (s.e. = 0.30; p = 0.008), 0.97 (s.e. = 0.23; p < 0.001), and 0.96 (s.e. = 0.92; p = 0.294) respectively. Differences among patients diagnosed with minor stroke were like or worse than transient ischemic attack patients. Conclusions: Transient ischemic attack clinic patients may have functional and emotional impairments compared to the general population irrespective of final diagnosis. The presence of emotional symptoms or risk of developing anxiety or depression did not always fully recover and may increase