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An assessment of the bioaccumulation of estrone in Daphnia magna
The bioaccumulation of estrone by Daphnia magna was determined. Direct uptake via the aqueous medium occurred within the first 16 hours. A bioconcentration factor of 228 was established over all temporal periods. Ingestion via Chlorella vulgaris gave a partitioning factor of 24 which may approximate to a biomagnification factor assuming steady state conditions. These preliminary results indicate that the partitioning to Daphnia magna via the food source, Chorella vulgaris is less significant than bioconcentration
Co-expression of Gbeta 5 Enhances the Function of Two Ggamma Subunit-like Domain-containing Regulators of G Protein Signaling Proteins
Regulators of G protein signaling (RGS) stimulate the GTPase activity of G protein Galpha subunits and probably play additional roles. Some RGS proteins contain a Ggamma subunit-like (GGL) domain, which mediates a specific interaction with Gbeta 5. The role of such interactions in RGS function is unclear. RGS proteins can accelerate the kinetics of coupling of G protein-coupled receptors to G-protein-gated inwardly rectifying K+ (GIRK) channels. Therefore, we coupled m2-muscarinic acetylcholine receptors to GIRK channels in Xenopus oocytes to evaluate the effect of Gbeta 5 on RGS function. Co-expression of either RGS7 or RGS9 modestly accelerated GIRK channel kinetics. When Gbeta 5 was co-expressed with either RGS7 or RGS9, the acceleration of GIRK channel kinetics was strongly increased over that produced by RGS7 or RGS9 alone. RGS function was not enhanced by co-expression of Gbeta 1, and co-expression of Gbeta 5 alone had no effect on GIRK channel kinetics. Gbeta 5 did not modulate the function either of RGS4, an RGS protein that lacks a GGL domain, or of a functional RGS7 construct in which the GGL domain was omitted. Enhancement of RGS7 function by Gbeta 5 was not a consequence of an increase in the amount of plasma membrane or cytosolic RGS7 protein
Managing Dynamic Enterprise and Urgent Workloads on Clouds Using Layered Queuing and Historical Performance Models
The automatic allocation of enterprise workload to resources can be enhanced by being able to make what-if response time predictions whilst different allocations are being considered. We experimentally investigate an historical and a layered queuing performance model and show how they can provide a good level of support for a dynamic-urgent cloud environment. Using this we define, implement and experimentally investigate the effectiveness of a prediction-based cloud workload and resource management algorithm. Based on these experimental analyses we: i.) comparatively evaluate the layered queuing and historical techniques; ii.) evaluate the effectiveness of the management algorithm in different operating scenarios; and iii.) provide guidance on using prediction-based workload and resource management
Don’t turn your back on the symptoms of psychosis : a proof-of-principle, quasi-experimental public health trial to reduce the duration of untreated psychosis in Birmingham, UK
Background: Reducing the duration of untreated psychosis (DUP) is an aspiration of international guidelines for first episode psychosis; however, public health initiatives have met with mixed results. Systematic reviews suggest that greater focus on the sources of delay within care pathways, (which will vary between healthcare settings) is needed to achieve sustainable reductions in DUP (BJP 198: 256-263; 2011).
Methods/Design: A quasi-experimental trial, comparing a targeted intervention area with a ‘detection as usual’ area in the same city. A proof-of–principle trial, no a priori assumptions are made regarding effect size; key outcome will be an estimate of the potential effect size for a definitive trial. DUP and number of new cases will be collected over an 18-month period in target and control areas and compared; historical data on DUP collected in both areas over the previous three years, will serve as a benchmark. The intervention will focus on reducing two significant DUP component delays within the overall care pathway: delays within the mental health service and help-seeking delay.
Discussion: This pragmatic trial will be the first to target known delays within the care pathway for those with a first episode of psychosis. If successful, this will provide a generalizable methodology that can be implemented in a variety of healthcare contexts with differing sources of delay.
Trial registration: http://www.controlled-trials.com/ISRCTN45058713
Keywords: Public mental health campaign, First-episode psychosis, Early detection, Duration of untreated psychosis, Youth mental healt
SUSY parameter determination at the LHC using cross sections and kinematic edges
We study the determination of supersymmetric parameters at the LHC from a
global fit including cross sections and edges of kinematic distributions. For
illustration, we focus on a minimal supergravity scenario and discuss how well
it can be constrained at the LHC operating at 7 and 14 TeV collision energy,
respectively. We find that the inclusion of cross sections greatly improves the
accuracy of the SUSY parameter determination, and allows to reliably extract
model parameters even in the initial phase of LHC data taking with 7 TeV
collision energy and 1/fb integrated luminosity. Moreover, cross section
information may be essential to study more general scenarios, such as those
with non-universal gaugino masses, and distinguish them from minimal,
universal, models.Comment: 22 pages, 8 figure
The Role of Primary Care in Service Provision for People with Severe Mental Illness in the United Kingdom
Severe mental illness is a serious and potentially life changing set of conditions. This paper describes and analyses patient characteristics and service usage over one year of a representative cohort of people with a diagnosis of severe mental illness across England, including contacts with primary and secondary care and continuity of care
Measurements of neutral vector resonance in Higgsless models at the LHC
In Higgsless models, new vector resonances appear to restore the unitarity of
the W_L W_L scattering amplitude without the Higgs boson. In the ideal
delocalized three site Higgsless model, one of large prodcution cross section
of the neutral vector resonance (Z') at the Large Hadron Collider is the
W-associated production, pp \to Z'W \to WWW. Although the dileptonic decay
channnel, l\nu l'\nu 'jj, is experimentally clean to search for the Z' signals,
it is difficult to reconstruct the Z' invariant mass due to the two neutrinos
in the final state. We study collider signatures of Z' using the
M_{T2}-Assisted On-Shell (MAOS) reconstruction of the missing neutrino momenta.
We show the prospect of the Z' mass determination in the channel, l\nu l'\nu
'jj, at the Large Hadron Collider.Comment: 16 pages, 6 figures, 5 tables; v2: references added, minor
corrections, version published in JHE
Momentum asymmetries as CP violating observables
Three body decays can exhibit CP violation that arises from interfering
diagrams with different orderings of the final state particles. We construct
several momentum asymmetry observables that are accessible in a hadron collider
environment where some of the final state particles are not reconstructed and
not all the kinematic information can be extracted. We discuss the
complications that arise from the different possible production mechanisms of
the decaying particle. Examples involving heavy neutralino decays in
supersymmetric theories and heavy Majorana neutrino decays in Type-I seesaw
models are examined.Comment: 20 pages, 9 figures. Clarifying comments and one reference added,
matches published versio
Natural Supersymmetry at the LHC
If the minimal supersymmetric standard model is the solution to the hierarchy
problem, the scalar top quark (stop) and the Higgsino should weigh around the
electroweak scale such as 200 GeV. A low messenger scale, which results in a
light gravitino, is also suggested to suppress the quantum corrections to the
Higgs mass parameters. Therefore the minimal model for natural supersymmetry is
a system with stop/Higgsino/gravitino whereas other superparticles are heavy.
We study the LHC signatures of the minimal system and discuss the discovery
potential and methods for the mass measurements.Comment: 19 pages, 6 figures, 1 tabl
Framework and indicator testing protocol for developing and piloting quality indicators for the UK quality and outcomes framework
Contains fulltext :
96936.pdf (publisher's version ) (Open Access)BACKGROUND: Quality measures should be subjected to a testing protocol before being used in practice using key attributes such as acceptability, feasibility and reliability, as well as identifying issues derived from actual implementation and unintended consequences. We describe the methodologies and results of an indicator testing protocol (ITP) using data from proposed quality indicators for the United Kingdom Quality and Outcomes Framework (QOF). METHODS: The indicator testing protocol involved a multi-step and methodological process: 1) The RAND/UCLA Appropriateness Method, to test clarity and necessity, 2) data extraction from patients' medical records, to test technical feasibility and reliability, 3) diaries, to test workload, 4) cost-effectiveness modelling, and 5) semi-structured interviews, to test acceptability, implementation issues and unintended consequences. Testing was conducted in a sample of representative family practices in England. These methods were combined into an overall recommendation for each tested indicator. RESULTS: Using an indicator testing protocol as part of piloting was seen as a valuable way of testing potential indicators in 'real world' settings. Pilot 1 (October 2009-March 2010) involved thirteen indicators across six clinical domains and twelve indicators passed the indicator testing protocol. However, the indicator testing protocol identified a number of implementation issues and unintended consequences that can be rectified or removed prior to national roll out. A palliative care indicator is used as an exemplar of the value of piloting using a multiple attribute indicator testing protocol - while technically feasible and reliable, it was unacceptable to practice staff and raised concerns about potentially causing actual patient harm. CONCLUSIONS: This indicator testing protocol is one example of a protocol that may be useful in assessing potential quality indicators when adapted to specific country health care settings and may be of use to policy-makers and researchers worldwide to test the likely effect of implementing indicators prior to roll out. It builds on and codifies existing literature and other testing protocols to create a field testing methodology that can be used to produce country specific quality indicators for pay-for-performance or quality improvement schemes
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