9,792 research outputs found
Model-independent measurement of the e (Formula presented.) e (Formula presented.) (Formula presented.) HZ cross section at a future e (Formula presented.) e (Formula presented.) linear collider using hadronic Z decays
A future e+e- collider, such as the ILC or CLIC, would allow the Higgs sector
to be probed with a precision significantly beyond that achievable at the
High-Luminosity LHC. A central part of the Higgs programme at an e+e- collider
is the model-independent determination of the absolute Higgs couplings to
fermions and to gauge bosons. Here the measurement of the e+e-->HZ
Higgsstrahlung cross section, using the recoil mass technique, sets the
absolute scale for all Higgs coupling measurements. Previous studies have
considered e+e- ->ZH with Z->l+l-, where l = electron or muon. In this paper it
is shown for the first time that a near model-independent recoil mass technique
can be extended to the hadronic decays of the Z boson. Because the branching
ratio for Z->qq is approximately ten times greater than for Z->l+l-, this
method is statistically more powerful than using the leptonic decays. For an
integrated luminosity of 500 fb-1 at a centre-of-mass energy of 350 GeV at
CLIC, the e+e-->HZ cross section can be measured to 1.8 % using the hadronic
recoil mass technique. A similar precision is found for the ILC operating at
350 GeV. The centre-of-mass dependence of this measurement technique is
discussed, arguing for the initial operation of a future linear collider at
just above the top-pair production threshold.The author would like to thank: colleagues in the CLICdp collaboration, in particular Christian Grefe, Philipp Roloff and André Sailer for their tireless work in generating the CLIC MC samples used in this study; colleagues in the ILD detector concept for generating the ILC MC samples used for the results reported in Sect. 4; Aharon Levy and Lucie Linssen for their valuable comments on the first drafts of this paper; Aidan Robson, Sophie Redford and Philipp Roloff for their comments on the final drafts of this paper; and the UK STFC and CERN for their financial support.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1140/epjc/s10052-016-3911-
The influence of the experimental methodology on the QED theoretical uncertainties on the measurement of M-W at LEP
Previous studies of the QED systematic uncertainties on the LEP measurement
of the W-boson mass have used idealized event selections and fitting
procedures. In this paper, the Monte Carlo tandem of KoralW and YFSWW is used
to investigate how the full experimental mass extraction procedure affects
these estimates. It is found that the kinematic fitting used in the
experimental determination of the W-boson mass enhances the sensitivity to QED
corrections involving real photon production. It is concluded that the previous
estimates of the QED theoretical uncertainty on the LEP2 W-mass measurement may
be too small. A simple procedure for approximating the effect of the kinematic
fit at the level of the generated four fermions is proposed. This procedure
would allow previous theoretical studies to be repeated using a much closer
approximation of the real experimental mass extraction method. Finally, the
possibility of setting experimental limits on O(alpha) theoretical
uncertainties using identified e+e- -> W+W-gamma events is discussed
The Pandora software development kit for pattern recognition
The development of automated solutions to pattern recognition problems is
important in many areas of scientific research and human endeavour. This paper
describes the implementation of the Pandora Software Development Kit, which
aids the process of designing, implementing and running pattern recognition
algorithms. The Pandora Application Programming Interfaces ensure simple
specification of the building-blocks defining a pattern recognition problem.
The logic required to solve the problem is implemented in algorithms. The
algorithms request operations to create or modify data structures and the
operations are performed by the Pandora framework. This design promotes an
approach using many decoupled algorithms, each addressing specific topologies.
Details of algorithms addressing two pattern recognition problems in High
Energy Physics are presented: reconstruction of events at a high-energy e+e-
linear collider and reconstruction of cosmic ray or neutrino events in a liquid
argon time projection chamber.This work was funded in part by the UK Science and Technology Facilities Council and by the European Union under the Advanced European Infrastructures for Detectors and Accelerators (AIDA) project.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1140/epjc/s10052-015-3659-
Protein Kinase A Subunit α Catalytic and A Kinase Anchoring Protein 79 in Human Placental Mitochondria
Components of protein phosphorylation signalling systems have been discovered in mitochondria and it has been proposed that these molecules modulate processes including oxidative phosphorylation, apoptosis and steroidogenesis
Magnetoelastic coupling in the cobalt adipate metal-organic framework from quasi-harmonic lattice dynamics
Magnetic interactions in hybrid materials are poorly understood compared to those in purely inorganic materials. The high flexibility of many metal-organic systems introduces a strong temperature dependence of the magnetic exchange interactions owing to changes in the crystal structure. Here, we study the cobalt adipate system, for which anisotropic thermal expansion was recently shown to be a result of magnetoelastic coupling. The combination of density functional theory with quasi-harmonic lattice dynamics is shown to be a powerful tool for describing temperature dependent thermodynamic potentials that determine magnetic interactions. It is demonstrated that the effect of phonons can be sufficient to switch the preference for ferromagnetic versus antiferromagnetic ordering
Novel sialic acid derivatives lock open the 150-loop of an influenza A virus group-1 sialidase
This work was supported by the Medical Research Council and the Scottish Funding Council.Influenza virus sialidase has an essential role in the virus’ life cycle. Two distinct groups of influenza A virus sialidases have been established, that differ in the flexibility of the ‘150-loop’, providing a more open active site in the apo form of the group-1 compared to group-2 enzymes. In this study we show, through a multidisciplinary approach, that novel sialic acid-based derivatives can exploit this structural difference and selectively inhibit the activity of group-1 sialidases. We also demonstrate that group-1 sialidases from drug-resistant mutant influenza viruses are sensitive to these designed compounds. Moreover, we have determined, by protein X-ray crystallography, that these inhibitors lock open the group-1 sialidase flexible 150-loop, in agreement with our molecular modelling prediction. This is the first direct proof that compounds may be developed to selectively target the pandemic A/H1N1, avian A/H5N1 and other group-1 sialidase-containing viruses, based on an open 150-loop conformation of the enzyme.Publisher PDFPeer reviewe
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The Pandora multi-algorithm approach to automated pattern recognition in LAr TPC detectors
The development and operation of Liquid Argon Time Projection Chambers (LAr TPCs) for neutrino physics has created a need for new approaches to pattern recognition, in order to fully exploit the superb imaging capabilities offered by this technology. The Pandora Software Development Kit provides functionality to aid the process of designing, implementing and running pattern recognition algorithms. It promotes the use of a multi-algorithm approach to pattern recognition: individual algorithms each address a specific task in a particular topology; a series of many tens of algorithms then carefully builds-up a picture of the event. The input to the Pandora pattern recognition is a list of 2D Hits. The output from the chain of over 70 algorithms is a hierarchy of reconstructed 3D Particles, each with an identified particle type, vertex and direction
The prevalence of uterine fundal pressure during the second stage of labour for women giving birth in health facilities: a systematic review and meta-analysis.
Background
Uterine fundal pressure involves a birth attendant pushing on the woman’s uterine fundus to assist vaginal birth. It is used in some clinical settings, though guidelines recommend against it. This systematic review aimed to determine the prevalence of uterine fundal pressure during the second stage of labour for women giving birth vaginally at health facilities.
Methods
The population of interest were women who experienced labour in a health facility and in whom vaginal birth was anticipated. The primary outcome was the use of fundal pressure during second stage of labour. MEDLINE, EMBASE, CINAHL and Global Index Medicus databases were searched for eligible studies published from 1 January 2000 onwards. Meta-analysis was conducted to determine a pooled prevalence, with subgroup analyses to explore heterogeneity.
Results
Eighty data sets from 76 studies (n = 898,544 women) were included, reporting data from 22 countries. The prevalence of fundal pressure ranged from 0.6% to 69.2% between studies, with a pooled prevalence of 23.2% (95% CI 19.4–27.0, I2 = 99.97%). There were significant differences in prevalence between country income level (p < 0.001, prevalence highest in lower-middle income countries) and method of measuring use of fundal pressure (p = 0.001, prevalence highest in studies that measured fundal pressure based on women’s self-report).
Conclusions
The use of uterine fundal pressure on women during vaginal birth in health facilities is widespread. Efforts to prevent this potentially unnecessary and harmful practice are needed
Description and process evaluation of pharmacists’ interventions in a pharmacist-led information technology-enabled multicentre cluster randomised controlled trial for reducing medication errors in general practice (PINCER trial)
Objective
To undertake a process evaluation of pharmacists' recommendations arising in the context of a complex IT-enabled pharmacist-delivered randomised controlled trial (PINCER trial) to reduce the risk of hazardous medicines management in general practices.
Methods
PINCER pharmacists manually recorded patients’ demographics, details of interventions recommended, actions undertaken by practice staff and time taken to manage individual cases of hazardous medicines management. Data were coded and double entered into SPSS v15, and then summarised using percentages for categorical data (with 95% CI) and, as appropriate, means (SD) or medians (IQR) for continuous data.
Key findings
Pharmacists spent a median of 20 minutes (IQR 10, 30) reviewing medical records, recommending interventions and completing actions in each case of hazardous medicines management. Pharmacists judged 72% (95%CI 70, 74) (1463/2026) of cases of hazardous medicines management to be clinically relevant.
Pharmacists recommended 2105 interventions in 74% (95%CI 73, 76) (1516/2038) of cases and 1685 actions were taken in 61% (95%CI 59, 63) (1246/2038) of cases; 66% (95%CI 64, 68) (1383/2105) of interventions recommended by pharmacists were completed and 5% (95%CI 4, 6) (104/2105) of recommendations were accepted by general practitioners (GPs), but not completed at the end of the pharmacists’ placement; the remaining recommendations were rejected or considered not relevant by GPs.
Conclusions
The outcome measures were used to target pharmacist activity in general practice towards patients at risk from hazardous medicines management. Recommendations from trained PINCER pharmacists were found to be broadly acceptable to GPs and led to ameliorative action in the majority of cases. It seems likely that the approach used by the PINCER pharmacists could be employed by other practice pharmacists following appropriate training
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