HERAFitter Alekhin, S.; Behnke, O.; Belov, P. ...
The European physical journal. C, Particles and fields,
07/2015, Letnik:
75, Številka:
7
Journal Article
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HERAFitter is an open-source package that provides a framework for the determination of the parton distribution functions (PDFs) of the proton and for many different kinds of analyses in Quantum ...Chromodynamics (QCD). It encodes results from a wide range of experimental measurements in lepton–proton deep inelastic scattering and proton–proton (proton–antiproton) collisions at hadron colliders. These are complemented with a variety of theoretical options for calculating PDF-dependent cross section predictions corresponding to the measurements. The framework covers a large number of the existing methods and schemes used for PDF determination. The data and theoretical predictions are brought together through numerous methodological options for carrying out PDF fits and plotting tools to help to visualise the results. While primarily based on the approach of collinear factorisation, HERAFitter also provides facilities for fits of dipole models and transverse-momentum dependent PDFs. The package can be used to study the impact of new precise measurements from hadron colliders. This paper describes the general structure of HERAFitter and its wide choice of options.
We study the rapidity dependence of the central exclusive production cross sections of C-even mesons in
pA
and
AA
collisions, where
A
is a heavy ion. We observe qualitatively different behaviour of ...the contributions arising from
γ
-Odderon and Pomeron–Pomeron fusion mechanisms. This can be used to extract the Odderon signal from the events of
f
2
mesons exclusively produced in the forward region. Estimates, obtained using expected values of the Odderon cross section, indicate that the
γ
-Odderon contribution may exceed by a few times the Pomeron-induced background in Pb–Pb collisions. Moreover, the Odderon effect can be clearly seen in terms of the asymmetry in
pA
and
AA
collisions with the beam and target reversed. It is particularly interesting to note that the asymmetry for
γ
-Odderon fusion reaches its maximum value close to 1 in the forward direction, whereas the asymmetry for the Pomeron–Pomeron fusion contribution is small. The role of additional interactions of the
f
2
meson with nucleons in the heavy ion, and also the contributions from secondary Reggeons, are estimated. The photon–Odderon contribution has a large normalisation uncertainty but the enhanced cross-section in the forward region combined with a large asymmetry increases the chance of experimentally detecting the Odderon.
Low gain avalanche detectors can measure charged particle fluences with high speed and spatial precision, and are a promising technology for radiation monitoring and dosimetry. A detector has been ...tested in a medical linac where single particles were observed with a time resolution of 50 ps. The integrated response is similar to a standard ionising chamber but with a spatial precision twenty times finer, and a temporal precision over 100 million times better, with the capability to measure the charge deposited by a single linac pulse. The unprecedented resolving power allows the structure of the ∼3 μs linac pulses to be viewed and the 350 ps sub-pulses in the train to be observed.
Current methods of oxygen uptake (VO
2
) kinetics data handling may be too simplistic for the complex physiology involved in the underlying physiological processes. Therefore, the aim of this study ...was to quantify the VO
2
kinetics to steady state across the full range of sub-ventilatory threshold work rates, with a particular focus on the VO
2
onset kinetics. Ten healthy, moderately trained males participated in five bouts of cycling. Each bout involved 10 min at a percentage of the subject's ventilation threshold (30, 45, 60, 75, 90%) from unloaded cycling. The VO
2
kinetics was quantified using the conventional mono-exponential time constant (tau, τ), as well as the new methods for VO
2
onset kinetics. Compared to linear modeling, non-linear modeling caused a deterioration of goodness of fit (main effect,
p
< 0.001) across all exercise intensities. Remainder kinetics were also improved using a modified application of the mono-exponential model (main effect,
p
< 0.001). Interestingly, the slope from the linear regression of the onset kinetics data is similar across all subjects and absolute exercise intensities, and thereby independent of subject fitness and τ. This could indicate that there are no functional limitations between subjects during this onset phase, with limitations occurring for the latter transition to steady state. Finally, the continuing use of mono-exponential modeling could mask important underlying physiology of more instantaneous VO
2
responses to steady state. Consequently, further research should be conducted on this new approach to VO
2
onset kinetics.
Circadian clocks are encoded by a transcription-translation feedback loop that aligns energetic processes with the solar cycle. We show that genetic disruption of the clock activator BMAL1 in ...skeletal myotubes and fibroblasts increased levels of the hypoxia-inducible factor 1α (HIF1α) under hypoxic conditions. Bmal1−/− myotubes displayed reduced anaerobic glycolysis, mitochondrial respiration with glycolytic fuel, and transcription of HIF1α targets Phd3, Vegfa, Mct4, Pk-m, and Ldha, whereas abrogation of the clock repressors CRY1/2 stabilized HIF1α in response to hypoxia. HIF1α bound directly to core clock gene promoters, and, when co-expressed with BMAL1, led to transactivation of PER2-LUC and HRE-LUC reporters. Further, genetic stabilization of HIF1α in Vhl−/− cells altered circadian transcription. Finally, induction of clock and HIF1α target genes in response to strenuous exercise varied according to the time of day in wild-type mice. Collectively, our results reveal bidirectional interactions between circadian and HIF pathways that influence metabolic adaptation to hypoxia.
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•Clock disruption in skeletal muscle reduces HIF1α activity and anaerobic glycolysis•Genetic and hypoxic stabilization of HIF alters circadian transcription•Maximal induction of HIF in response to exercise occurs in the early active period
Peek et al. demonstrate that circadian clock disruption impairs oxygen sensing through HIF and anaerobic glycolysis in skeletal muscle. In turn, HIF upregulation lengthens the circadian period. HIF is primed by the clock to respond more robustly to exercise during the early active period.
To evaluate the impact of a pharmacy-directed pain management service (PPMS) designed to optimize analgesic pharmacotherapy, minimize adverse events, and improve patients' experience of pain ...management.
A retrospective analysis was conducted to evaluate the PPMS consisting of 3 dedicated pain management clinical pharmacists who perform both consult-based and stewardship functions. Multiple measures of opioid use and associated patient satisfaction outcomes during 3-year periods before and after implementation of the PPMS were compared.
Significant decreases in use of institutionally defined high-risk opioid medications (e.g., parenteral hydromorphone, fentanyl, transdermal fentanyl patches), a decrease in total institutional opioid use, increased coanalgesic and adjunctive medication use, and a decrease in rapid response team (RRT) and code blue events associated with opioid-induced oversedation were seen after service implementation. Despite decreased opioid use, available patient satisfaction data suggested ongoing improvement in associated Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey domains.
Our data highlights the impact of a pharmacy directed pain management service on institutional opioid use with available data suggesting improved patient satisfaction scores and indirect cost savings. Despite decreased opioid use, available patient satisfaction data suggested ongoing improvement in associated HCAHPS survey pain management domains.