4,060 research outputs found
Selection rules for J^PC Exotic Hybrid Meson Decay in Large-N_c
The coupling of a neutral hybrid {1,3,5...}^-+ exotic particle (or current)
to two neutral (hybrid) meson particles with the same J^PC and J=0 is proved to
be sub-leading to the usual large-N_c QCD counting. The coupling of the same
exotic particle to certain two - (hybrid) meson currents with the same J^PC and
J=0 is also sub-leading. The decay of a {1,3,5...}^-+ hybrid to eta pi^0, eta'
pi^0, eta' eta, eta(1295) pi^0, pi(1300)^0 pi0, eta(1440) pi^0, a_0(980)^0
sigma or f_0(980) sigma is sub-leading, assuming that these final state
particles are (hybrid) mesons in the limit of large N_c.Comment: 16 pages, LaTeX. Main paper shortened/rewritten and appendices
expanded. Implications for phenomenology of exotic hybrid mesons clarifie
Ex Vivo Electrochemical Measurement of Glutamate Release During Spinal Cord Injury
Excessive glutamate release following traumatic spinal cord injury (SCI) has been associated with exacerbating the extent of SCI. However, the mechanism behind sustained high levels of extracellular glutamate is unclear. Spinal cord segments mounted in a sucrose double gap recording chamber are an established model for traumatic spinal cord injury. We have developed a method to record, with micro-scale printed glutamate biosensors, glutamate release from ex vivo rat spinal cord segments following injury. This protocol would work equally well for similar glutamate biosensors
Do pharmacy practice standards effectively describe behaviour? Reviewing practice standards using a behavioural specificity framework
BACKGROUND: Guidelines and practice standards exist to communicate the conduct and behaviour expected of health care professionals and ensure consistent quality practice. It is important that they describe behaviours explicitly so they can be interpreted, enacted and measured with ease. The AACTT framework specifies behaviour in terms of the: Action to be performed, Actor who performs the action, Context where the action occurs, Target who the action is performed with/for and Time when the action is performed (AACTT). It provides the most up to date framework for specifying behaviours and is particularly relevant to complex behavioural problems that involve sequences of behaviours performed by different people. Behavioural specificity within pharmacy practice standards has not been explored. AIM: To determine if behaviours described in the Professional Practice Standards for Australian Pharmacists specify Action, Actor, Context, Target and Time. METHODS: Two researchers independently reviewed the scope and structure of the practice standards and one extracted action statements (behaviours) verbatim. Through an iterative process, the researchers modified and developed the existing AACTT definitions to operationalise them for application to review of the action statements in the practice standards. The operational definitions, decision criteria and curated examples were combined in a codebook. The definitions were consistently applied through a directed content analysis approach to evaluate all extracted action statements by one researcher. For consistency 20% was independently checked for agreement by a second researcher. RESULTS: A novel codebook to apply AACTT criteria to evaluate practice standards was developed. Application of this codebook identified 768 independent behaviours. Of these, 300 (39%) described at least one discrete observable action, none specified an actor, 25 (3%) specified context, 131 (17%) specified target and 88 (11%) specified time. CONCLUSION(S): The behaviours detailed in practice standards for Australian pharmacists do not consistently specify behaviours in terms of Action, Actor, Context, Target and Time. Developers in the pharmacy profession, and beyond, should consider the behavioural specificity of their documents to improve interpretability, usability and adherence to the behaviours detailed. This also has implications for the development and evaluation of interventions to change such behaviours and improve quality of care
Use of professional practice guidance resources in pharmacy: a cross-sectional nationwide survey of pharmacists, intern pharmacists, and pharmacy students
BACKGROUND: Variations in practice are commonplace in healthcare where health professionals, such as pharmacists act as autonomous practitioners. This is evident in simulated patient studies, where pharmacists practice does not meet widely accepted standards for medicines supply or treatment of an ailment. To promote best pharmacy practice a myriad of guidance resources including practice guidelines, codes and standards are produced by professional organisations. These resources provide a framework for pharmacy practice and endeavour to facilitate consistency in provision of pharmacy-based services to consumers. Despite their role in specifying essential pharmacist behaviours, there is limited research exploring if and how these resources are used in practice. OBJECTIVE: To characterise Australian pharmacists' use of the Pharmaceutical Society of Australia's Code of Ethics, Professional Practice Guidelines and Professional Practice Standards. METHODS: A cross-sectional, self-administered, electronic survey of registered pharmacists, intern pharmacists and pharmacy students living in Australia was conducted in July 2020. Questions considered use of professional practice resources (by resource group) in the preceding 12 months. Data were analysed descriptively. RESULTS: Of 601 responses included in the analysis 462 (76.9%) of respondents were registered pharmacists, 88 (14.6%) pharmacy students and 51 (8.5%) intern pharmacists. Interns and students accessed overarching practice resources, such as the Professional Practice Standards, Code of Ethics and Dispensing Practice Guidelines more frequently than practising pharmacists. Pharmacists accessed professional practice guidelines, such as Practice Guidelines for the Provision of Immunisation Services Within Pharmacy, more often than students. More pharmacists than interns and students indicated that they would access guidelines to resolve practice and patient care issues. All resources except the Professional Practice Standards for Pharmacists (67.4%) were accessed by less than 50% of respondents in the preceding 12-month period. Reasons for not accessing resources varied between participant and resource groups, and generally were due to a lack of awareness of the resource or not considering them necessary for the individual's practice. CONCLUSION(S): Access and use patterns for professional practice guidance resources change with experience. Professional organisations responsible for developing resources should consider these patterns when designing and reviewing resources and related policies. To ensure resources are meeting the needs of the profession, students, interns, and pharmacists should be involved in the review of and design of further resources
Thermal Evolution of Compact Stars
A collection of modern, field-theoretical equations of state is applied to
the investigation of cooling properties of compact stars. These comprise
neutron stars as well as hypothetical strange matter stars, made up of
absolutely stable 3-flavor strange quark matter. Various uncertainties in the
behavior of matter at supernuclear densities, e.g., hyperonic degrees of
freedom, behavior of coupling strengths in matter, pion and meson condensation,
superfluidity, transition to quark matter, absolute stability of strange quark
matter, and last but not least the many-body technique itself are tested
against the body of observed cooling data.Comment: 41 pages, revised versio
The fate of Reissner-Nortstr\"{o}m black hole in the Einstein-Yang-Mills-Higgs system
We study about an evaporating process of black holes in SO(3)
Einstein-Yang-Mills-Higgs system. We consider a massless scalar field which
couple neither with the Yang-Mills field nor with the Higgs field surrounding
the black hole. We discuss differences in evaporating rate between a monopole
black hole and a Reissner-Nortstr\"{o}m (RN) black hole.Comment: 9 pages, 8 figure
Observers in an accelerated universe
If the current acceleration of our Universe is due to a cosmological
constant, then a Coleman-De Luccia bubble will nucleate in our Universe. In
this work, we consider that our observations could be likely in this framework,
consisting in two infinite spaces, if a foliation by constant mean curvature
hypersurfaces is taken to count the events in the spacetime. Thus, we obtain
and study a particular foliation, which covers the existence of most observers
in our part of spacetime.Comment: revised version, accepted in EPJ
Hybrid Meson Decay Phenomenology
The phenomenology of a newly developed model of hybrid meson decay is
developed. The decay mechanism is based on the heavy quark expansion of QCD and
the strong coupling flux tube picture of nonperturbative glue. A comprehensive
list of partial decay widths of a wide variety of light, , ,
and hybrid mesons is presented. Results which appear approximately
universal are highlighted along with those which distinguish different hybrid
decay models. Finally, we examine several interesting hybrid candidates in
detail.Comment: 37 pages, 2 figures, 6 tables, Revte
Effect of hyperon bulk viscosity on neutron-star r-modes
Neutron stars are expected to contain a significant number of hyperons in
addition to protons and neutrons in the highest density portions of their
cores. Following the work of Jones, we calculate the coefficient of bulk
viscosity due to nonleptonic weak interactions involving hyperons in
neutron-star cores, including new relativistic and superfluid effects. We
evaluate the influence of this new bulk viscosity on the gravitational
radiation driven instability in the r-modes. We find that the instability is
completely suppressed in stars with cores cooler than a few times 10^9 K, but
that stars rotating more rapidly than 10-30% of maximum are unstable for
temperatures around 10^10 K. Since neutron-star cores are expected to cool to a
few times 10^9 K within seconds (much shorter than the r-mode instability
growth time) due to direct Urca processes, we conclude that the gravitational
radiation instability will be suppressed in young neutron stars before it can
significantly change the angular momentum of the star.Comment: final PRD version, minor typos etc correcte
Positivity of Entropy in the Semi-Classical Theory of Black Holes and Radiation
Quantum stress-energy tensors of fields renormalized on a Schwarzschild
background violate the classical energy conditions near the black hole.
Nevertheless, the associated equilibrium thermodynamical entropy by
which such fields augment the usual black hole entropy is found to be positive.
More precisely, the derivative of with respect to radius, at fixed
black hole mass, is found to vanish at the horizon for {\it all} regular
renormalized stress-energy quantum tensors. For the cases of conformal scalar
fields and U(1) gauge fields, the corresponding second derivative is positive,
indicating that has a local minimum there. Explicit calculation
shows that indeed increases monotonically for increasing radius and
is positive. (The same conclusions hold for a massless spin 1/2 field, but the
accuracy of the stress-energy tensor we employ has not been confirmed, in
contrast to the scalar and vector cases). None of these results would hold if
the back-reaction of the radiation on the spacetime geometry were ignored;
consequently, one must regard as arising from both the radiation
fields and their effects on the gravitational field. The back-reaction, no
matter how "small",Comment: 19 pages, RevTe
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