56 research outputs found
Investigation of the Lightest Hybrid Meson Candidate with a Coupled-Channel Analysis of -, - and -Data
Based on new insights from two recent coupled-channel analyses of
annihilation together with -scattering data and of data, this
paper aims at a better understanding of the spin-exotic resonances in
the light meson sector. The Crystal Barrel Collaboration observed the
-wave in annihilations in flight for the first time with the
coupling to in the reaction
with a sophisticated coupled-channel approach. Another refined coupled-channel
analysis of the P- and D-waves in the and system
based on data measured at COMPASS has been performed by the JPAC group. In that
study the two spin-exotic signatures listed in the PDG, the and
, with a separate coupling to and can
be described by a single pole. In this paper, both analyses, the one with the
three annihilation channels into ,
and and 11 different -scattering data sets and the one
with the P- and D-wave data in the and systems
measured at COMPASS, are subjected to a combined coupled channel analysis. By
utilizing the K-matrix approach and realizing the analyticity via
Chew-Mandelstam functions the wave can be well described by a single
pole for both systems, and . The mass and width of
the -pole are measured to be (1561.6 \, \pm \, 3.0 \,
^{+6.6}_{-2.6}\,)\, \mathrm{MeV/c}^2 and (388.1 \, \pm \, 5.4 \,
^{+0.2}_{-14.1}\,)\, \mathrm{MeV}.Comment: 5 pages, 2 figures, 1 tabl
Radiographic cortical thickness parameters as predictors of rotational alignment in proximal tibial shaft fractures: a cadaveric study
AIM The treatment of tibial fractures with an intramedullary nail is an established procedure. However, torsional control remains challenging using intraoperatively diagnostic tools. Radiographic tools such as the Cortical Step Sign (CSS) and the Diameter Difference Sign (DDS) may serve as tools for diagnosing a relevant malrotation. The aim of this study was to investigate the effect of torsional malalignment on CSS and DDS parameters and to construct a prognostic model to detect malalignment. METHODS A proximal tibial shaft fracture was set in human tibiae. Torsion was set stepwise from 0° to 30° in external and internal torsion. Images were obtained with a C-arm and transferred to a PC for measuring the medical cortical thickness (MCT), lateral cortical thickness (LCT), tibial diameter (TD) in AP and the anterior cortical thickness (ACT) as well as the posterior cortical thickness (PCT) and the transverse diameter (TD) of the proximal and the distal main fragment. RESULTS There were significant differences between the various degrees of torsion for each of the absolute values of the examined variables. The parameters with the highest correlation were TD, LCT and ACT. A model combining ACT, LCT, PCT and TD lateral was most suitable model in identifying torsional malalignment. The best prediction of clinically relevant torsional malalignment, namely 15°, was obtained with the TD and the ACT. CONCLUSION This study shows that the CSS and DDS are useful tools for the intraoperative detection of torsional malalignment in proximal tibial shaft fractures and should be used to prevent maltorsion
Using Y-chromosome capture enrichment to resolve haplogroup H2 shows new evidence for a two-Path Neolithic expansion to Western Europe
Uniparentally-inherited markers on mitochondrial DNA (mtDNA) and the non-recombining regions of the Y chromosome (NRY), have been used for the past 30 years to investigate the history of humans from a maternal and paternal perspective.Researchers have preferred mtDNA due to its abundance in the cells, and comparatively high substitution rate. Conversely, the NRY is less susceptible to back mutations and saturation, and is potentially more informative than mtDNA owing to its longer sequence length. However, due to comparatively poor NRY coverage via shotgun sequencing, and the relatively low and biased representation of Y-chromosome variants on capture arrays such as the 1240K, ancient DNA studies often fail to utilize the unique perspective that the NRY can yield.Here we introduce a new DNA enrichment assay, coined YMCA (Y-mappable capture assay), that targets the “mappable” regions of the NRY. We show that compared to low-coverage shotgun sequencing and 1240K capture, YMCA significantly improves the coverage and number of sites hit on the NRY, increasing the number of Y-haplogroup informative SNPs, and allowing for the identification of previously undiscovered variants.To illustrate the power of YMCA, we show that the analysis of ancient Y-chromosome lineages can help to resolve Y-chromosomal haplogroups. As a case study, we focus on H2, a haplogroup associated with a critical event in European human history: the Neolithic transition. By disentangling the evolutionary history of this haplogroup, we further elucidate the two separate paths by which early farmers expanded from Anatolia and the Near East to western Europe.Competing Interest StatementThe authors have declared no competing interest.Introduction Results and Discussion - Validating the performance of YMCA - Application of YMCA to YHG H2 as a case study - Identifying diagnostic SNPs for improved YHG H2 resolution Discussion Materials and Methods - Data - Contamination quality filtering - Method of Y Haplogroup Assignment - Comparing the Performance of our Y-capture Array Phylogenetic Tree Reconstructio
Ten millennia of hepatitis B virus evolution
Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between similar to 10,500 and similar to 400 years ago. We date the most recent common ancestor of all HBV lineages to between similar to 20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for similar to 4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic.Molecular Technology and Informatics for Personalised Medicine and Healt
PANDA Phase One - PANDA collaboration
The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of hadron-, nuclear- and atomic physics experiments. The future antiProton ANnihilations at DArmstadt (PANDA or P¯ANDA) experiment at FAIR will offer a broad physics programme, covering different aspects of the strong interaction. Understanding the latter in the non-perturbative regime remains one of the greatest challenges in contemporary physics. The antiproton–nucleon interaction studied with PANDA provides crucial tests in this area. Furthermore, the high-intensity, low-energy domain of PANDA allows for searches for physics beyond the Standard Model, e.g. through high precision symmetry tests. This paper takes into account a staged approach for the detector setup and for the delivered luminosity from the accelerator. The available detector setup at the time of the delivery of the first antiproton beams in the HESR storage ring is referred to as the Phase One setup. The physics programme that is achievable during Phase One is outlined in this paper
Precision resonance energy scans with the PANDA experiment at FAIR: Sensitivity study for width and line shape measurements of the X(3872)
This paper summarises a comprehensive Monte Carlo simulation study for precision resonance energy scan measurements. Apart from the proof of principle for natural width and line shape measurements of very narrow resonances with PANDA, the achievable sensitivities are quantified for the concrete example of the charmonium-like X(3872) state discussed to be exotic, and for a larger parameter space of various assumed signal cross-sections, input widths and luminosity combinations. PANDA is the only experiment that will be able to perform precision resonance energy scans of such narrow states with quantum numbers of spin and parities that differ from J P C = 1 - -
Ten millennia of hepatitis B virus evolution
Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between ~10,500 and ~400 years ago. We date the most recent common ancestor of all HBV lineages to between ~20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for ~4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic
Coupled channel partial wave analysis of two-photon reactions at BESIII
In dieser Arbeit wurden die Zwei-Photon-Reaktionen und untersucht. Hierfür wurden Datensätze im Strahlenenergiebereich zwischen 3,7-4,7 GeV verwendet des BESIII Experiments verwendet.
Im Rahmen der Datenselektion konnten mithilfe eventbasierter Untergrundsubtraktionsmethoden Daten mit vernachlässigterem Untergrundanteil gewonnen werden.
Die Daten wurden mithilfe des K-Matrix-Formalismus im Rahmen des P-Vektor-Ansatzes beschrieben.
Für die Resonanzen , , , , , , , , und wurden die Zwei-Photon-Kopplungsstärken durch Extraktion der Pol-Residuen der F-Vektor-Amplitude in der komplexen Energieebene bestimmt.
Darüber hinaus wurden die totalen und differentiellen Wirkungsquerschnitte gemessen.
Schließlich wurde eine umfassende Studie der statistischen und systematischen Unsicherheiten durchgeführt
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