268 research outputs found
Optimization of Multi-Stack Exhaust Systems - New System Design Application
Both analytical and numerical optimization
methods have been developed to optimize multi-stack
exhaust systems for application in new system
designs. In these systems the combined airflow
capacity of the stacks equals the maximum laboratory
exhaust airflow. The theoretical analysis indicates
that the optimized design uses as little as 50% of the
design fan power annually. This paper presents the
system models, the optimization methods, and
describes appropriate applications
The emotional well-being of young people: a review of the literature.
Suicide is increasingly described by governments and policy-makers as a global public health problem. Between 1950 and 1995 global suicide rates have increased by 60%. In recent years concerns have been expressed in Scotland and the UK about rising suicide rates amongst children and young people and the accumulation of increasing evidence that the adoption of negative coping strategies is contributing to rising levels of deliberate self harm (DSH).This literature review was in part used and incorporated into chapter two of the final report, The emotional wellbeing of young people: final report of phase one of a 'Choose Life' research project in Aberdeenshire (March 2004-March 2007), which can be found at http://hdl.handle.net/10059/439
New Challenges in Psycho-Oncology Research III: A systematic review of psychological interventions for prostate cancer survivors and their partners: clinical and research implications
Abstract not availableSuzanne K. Chambers, Melissa K. Hyde, David P. Smith, Suzanne Hughes, Susan Yuill, Sam Egger, Dianne L. O'Connell, Kevin Stein, Mark Frydenberg, Gary Wittert, Jeff Dun
The selectivity, voltage-dependence and acid sensitivity of the tandem pore potassium channel TASK-1 : contributions of the pore domains
We have investigated the contribution to ionic
selectivity of residues in the selectivity filter and pore
helices of the P1 and P2 domains in the acid sensitive
potassium channel TASK-1. We used site directed mutagenesis
and electrophysiological studies, assisted by structural
models built through computational methods. We have
measured selectivity in channels expressed in Xenopus
oocytes, using voltage clamp to measure shifts in reversal
potential and current amplitudes when Rb+ or Na+ replaced
extracellular K+. Both P1 and P2 contribute to selectivity,
and most mutations, including mutation of residues in the
triplets GYG and GFG in P1 and P2, made channels nonselective.
We interpret the effects of these—and of other
mutations—in terms of the way the pore is likely to be
stabilised structurally. We show also that residues in the
outer pore mouth contribute to selectivity in TASK-1.
Mutations resulting in loss of selectivity (e.g. I94S, G95A)
were associated with slowing of the response of channels to
depolarisation. More important physiologically, pH sensitivity
is also lost or altered by such mutations. Mutations
that retained selectivity (e.g. I94L, I94V) also retained their
response to acidification. It is likely that responses both to
voltage and pH changes involve gating at the selectivity filter
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The challenges and opportunities for implementing group antenatal care ('Pregnancy Circles') as part of standard NHS maternity care: A co-designed qualitative study
OBJECTIVE: To identify the challenges and opportunities for rolling out a bespoke model of group antenatal care called Pregnancy Circles (PC) within the National Health Service: what kind of support and training is needed and what adaptations are appropriate, including during a pandemic when face-to-face interaction is limited.
DESIGN: Exploratory qualitative study (online focus group). Study co-designed with midwives. Data analysed thematically using an ecological model to synthesise.
SETTING: Five maternity services within the National Health Service.
PARTICIPANTS: Seven midwives who facilitated PCs. Three senior midwives with implementation experience participated in the co-design process.
FINDINGS: Three themes operating across the ecological model were identified: 'Implementing innovation', 'Philosophy of care' and 'Resource management'. Tensions were identified between group care's focus on relationships and professional autonomy, and concepts of efficiency within the NHS's market model of care. Midwives found protected time, training and ongoing support essential for developing the skills and confidence needed to deliver this innovative model of care. Integrating Pregnancy Circles with continuity of carer models was seen as the most promising opportunity for long-term implementation. Midwives perceived continuity and peer support as the most effective elements of the model and there was some evidence that the model may be robust enough to withstand adaptation to online delivery.
KEY CONCLUSIONS: Midwives facilitating group care enjoyed the relationships, autonomy and professional development the model offered. Harnessing this personal (micro-level) satisfaction is key to wider implementation. Group care is well aligned with current maternity policy but the challenges midwives face (temporal, practical and cultural) must be anticipated and addressed at macro and meso level for wider implementation to be sustainable. The PC model may be flexible enough to adapt to online delivery and extend continuity of care but further research is needed in these areas.
IMPLICATIONS FOR PRACTICE: Implementation of group care in the NHS requires senior leadership and expertise in change management, protected time for training and delivery of the model, and funding for equipment. Training and ongoing support, are vital for sustainability and quality control. There is potential for online delivery and integrating group care with continuity models
A pre-post study of behavioural determinants and practice change in Ugandan Clinical Officers
The data for this research was collected as part of a training course delivered by the Greater Manchester Critical Care Skills Institute in Gulu, Uganda. Travel, accommodation and associated costs were funded by Greater Manchester Critical Care Skills Institute. Members of the training team collected data and their time both in delivering the course and collecting data was unfunded i.e., voluntary (MJJ, RmC, HS, AS, SC, SW). Data collection was supported by other self-funded volunteers (HP, SR). Research design, data analysis and write up was conducted by unfunded volunteers (all authors). There was no formal role for the funding body in the study design, data collection, analysis or write up. However, authors of the paper are active members of the Greater Manchester Critical Care Skills Institute (AS, MJJ, RMc, HS, SC, SW).Peer reviewedPublisher PD
A pre-post study of behavioural determinants and practice change in Ugandan clinical officers
Background. Understanding the drivers of ‘provider behaviour’ has been highlighted as one of the six domains of behaviour change in strengthening healthcare systems.Objectives. To assess changes in healthcare provider behaviour, i.e. use of the Airway, Breathing, Circulation, Disability, Exposure (ABCDE) approach in acute illness management, after participating in a 1-day course on the assessment and management of acutely ill patients. We aimed to assess whether changes in psychological determinants of the ABCDE approach were associated with changes in the use of the approach.Methods. We used a pre-post design to study self-reported change in behaviour after a 1-day training course from pre-course to follow-up 1 month later. We also measured psychological determinants of behaviour immediately before and after and at 1-month follow-up. We explored if changes in psychological determinants were associated with change in practice 1 month later.Results. We found the following: firstly, use of the ABCDE approach increased at 1 month post-course from a median use of 50 - 90%. Secondly, the increase in the ABCDE approach was associated with a positive change in only one of the determinants of practice from pre- to post-course: perception of environmental determinants (r=0.323; p<0.05). Finally, there were no other significant associations with practice change or practice at follow-up.Conclusions. Change in perceptions of availability of resources was associated with increased use of an ABCDE approach, but evidence was limited owing to the pre-post design
Mechanisms for collaboration: a design and evaluation framework for multi-user interfaces
Multi-user interfaces are said to provide “natural” interaction in supporting collaboration, compared to individual and noncolocated technologies. We identify three mechanisms accounting for the success of such interfaces: high awareness of others' actions and intentions, high control over the interface, and high availability of background information. We challenge the idea that interaction over such interfaces is necessarily “natural” and argue that everyday interaction involves constraints on awareness, control, and availability. These constraints help people interact more smoothly. We draw from social developmental psychology to characterize the design of multi-user interfaces in terms of how constraints on these mechanisms can be best used to promote collaboration. We use this framework of mechanisms and constraints to explain the successes and failures of existing designs, then apply it to three case studies of design, and finally derive from them a set of questions to consider when designing and analysing multi-user interfaces for collaboration
Contesting the Dominant Discourse of Child Sexual Abuse: Sexual Subjects, Agency, and Ethics
Responding to previous scholars’ call to explore the complexities of child sexual abuse (CSA), this article presents narratives of CSA and scrutinizes a binary construction underpinning this discourse of CSA, namely, the positioning of children as powerless and adults as powerful. The narratives belong to three Indonesian young people who have had sexual interactions with adults when they were children. The findings demonstrate how this binary positioning has been both drawn upon and resisted in the ways participants understand their sexual experiences. This article contributes to the existing literature by providing analyses of some vignettes of everyday experiences of how children might be constituted as sexual subjects, including their capability to exercise agency, perform resistance, and negotiate ethics. The implications of the findings are discussed in relation to how the recognition of children as sexual subjects and their sexual agency might be beneficial for parents, educators, and counselors
Gating of a pH-Sensitive K2P Potassium Channel by an Electrostatic Effect of Basic Sensor Residues on the Selectivity Filter
K+ channels share common selectivity characteristics but exhibit a wide diversity in how they are gated open. Leak K2P K+ channels TASK-2, TALK-1 and TALK-2 are gated open by extracellular alkalinization. The mechanism for this alkalinization-dependent gating has been proposed to be the neutralization of the side chain of a single arginine (lysine in TALK-2) residue near the pore of TASK-2, which occurs with the unusual pKa of 8.0. We now corroborate this hypothesis by transplanting the TASK-2 extracellular pH (pHo) sensor in the background of a pHo-insensitive TASK-3 channel, which leads to the restitution of pHo-gating. Using a concatenated channel approach, we also demonstrate that for TASK-2 to open, pHo sensors must be neutralized in each of the two subunits forming these dimeric channels with no apparent cross-talk between the sensors. These results are consistent with adaptive biasing force analysis of K+ permeation using a model selectivity filter in wild-type and mutated channels. The underlying free-energy profiles confirm that either a doubly or a singly charged pHo sensor is sufficient to abolish ion flow. Atomic detail of the associated mechanism reveals that, rather than a collapse of the pore, as proposed for other K2P channels gated at the selectivity filter, an increased height of the energetic barriers for ion translocation accounts for channel blockade at acid pHo. Our data, therefore, strongly suggest that a cycle of protonation/deprotonation of pHo-sensing arginine 224 side chain gates the TASK-2 channel by electrostatically tuning the conformational stability of its selectivity filter
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