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Based on 7.33 fb−1 of e+e− collision data collected at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector, the experimental studies of the doubly Cabibbo-suppressed decays D+s→K+K+π− and D+s→K+K+π−π0 are reported. We determine the absolute branching fraction of D+s→K+K+π− to be (1.23+0.28−0.25(stat)±0.06(syst)) ×10−4. No significant signal of D+s→K+K+π−π0 is observed and the upper limit on its decay branching fraction at 90\% confidence level is set to be 1.7×10−4.
Based on 4.5 fb−1 of e+e− collision data accumulated at center-of-mass energies between 4599.53 MeV and 4698.82 MeV with the BESIII detector, the decay Λ+c→nK0Sπ+π0 is observed for the first time with a significance of 9.2σ. The branching fraction is measured to be (0.85±0.13±0.03)%, where the first uncertainty is statistical and the second systematic, which differs from the theoretical prediction based on isospin by 4.4σ. This indicates that there may be resonant contributions or some unknown dynamics in this decay.
Measurement of the e+e−→π+π− cross section between 600 and 900 MeV using initial state radiation
(2016)
We extract the e+e− →π+π− cross section in the energy range between 600 and 900 MeV, exploiting the method of initial state radiation. A data set with an integrated luminosity of 2.93 fb−1 taken at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider is used. The cross section is measured with a systematic uncertainty of 0.9%. We extract the pion form factor |Fπ|2 as well as the contribution of the measured cross section to the leading-order hadronic vacuum polarization contribution to (g−2)μ. We find this value to be aππ,LO μ (600–900 MeV) = (368.2 ±2.5stat±3.3sys) ·10−10, which is between the corresponding values using the BaBar or KLOE data.
The decays of χc2→K+K−π0, KSK±π∓ and π+π−π0 are studied with the ψ(3686) data samples collected with the Beijing Spectrometer (BESIII). For the first time, the branching fractions of χc2→K∗K¯¯¯¯¯, χc2→a±2(1320)π∓/a02(1320)π0 and χc2→ρ(770)±π∓ are measured. Here K∗K¯¯¯¯¯ denotes both K∗±K∓ and K∗0K¯¯¯¯¯0+c.c., and K∗ denotes the resonances K∗(892), K∗2(1430) and K∗3(1780). The observations indicate a strong violation of the helicity selection rule in χc2 decays into vector and pseudoscalar meson pairs. The measured branching fractions of χc2→K∗(892)K¯¯¯¯¯ are more than 10 times larger than the upper limit of χc2→ρ(770)±π∓, which is so far the first direct observation of a significant U-spin symmetry breaking effect in charmonium decays.
Using a data sample of (1.0087±0.0044)×1010 J/ψ decay events collected with the BESIII detector at the center-of-mass energy of s√=3.097 GeV, we present a search for the hyperon semileptonic decay Ξ0→Σ−e+νe which violates the ΔS=ΔQ rule. No significant signal is observed, and the upper limit on the branching fraction B(Ξ0→Σ−e+νe) is determined to be 1.6×10−4 at the 90% confidence level. This result improves the previous upper limit result by about one order of magnitude.
Using a data sample of (1.0087±0.0044)×1010 J/ψ decay events collected with the BESIII detector at the center-of-mass energy of s√=3.097 GeV, we present a search for the hyperon semileptonic decay Ξ0→Σ−e+νe which violates the ΔS=ΔQ rule. No significant signal is observed, and the upper limit on the branching fraction B(Ξ0→Σ−e+νe) is determined to be 1.6×10−4 at the 90% confidence level. This result improves the previous upper limit result by about one order of magnitude.
Meeting Abstract (DGU 2003) 67. Jahrestagung der Deutschen Gesellschaft für Unfallchirurgie 89. Tagung der Deutschen Gesellschaft für Orthopädie und Orthopädische Chirurgie 44. Tagung des Berufsverbandes der Fachärzte für Orthopädie Fragestellung Ziel dieser prospektiven Untersuchung ist die Analyse der Funktion und des Outcomes nach distaler Radiusfraktur in Abhängigkeit von Frakturtyp, Therapieform und Begeleitverletzungen. Berücksichtigt wurden diesbezüglich insbesondere auch neuere Implantate wie die volaren winkelstabilen Titanplatten und dorsale low profile Implantate. Methodik Innerhalb von 2 Jahren (01/01 bis 12/02) wurden insgesamt 150 Radiusfrakturen bei 145 Patienten (82 Frauen; 63 Männer) mit einem Durchschnittsalter von 51,8 (17-93) Jahren operativ versorgt. Die operative Versorgung erfolgte in 56,7 % der Fälle mittels volarer Plattenosteosynthese, davon wurde bei 60 % eine winkelstabile Platte eingesetzt. Die übrigen Frakturen wurden durch eine dorsale Platte (8%) bzw. durch Materialkombination Spickdraht/Schrauben und/oder Fixateur externe stabilisiert. Die radiologische und klinische Nachuntersuchung erfolgt frühestens 1 Jahr nach operativer Versorgung. Zusätzlich wird anhand eines Fragebogens der DASH - Score bestimmt. Ergebnisse Nach der AO-Klassifikation fanden sich in 47,7 % Typ A-, 8,6% Typ B- und 55,6% Typ C-Frakturen. Dabei fand sich bei 53,1 % eine relevante Begleitverletzung (Bandverletzungen 14,3 %; Handwurzelfrakturen 3,9 %; distale Ulnafrakturen 10,4%; TFC/Proc. styloideus ulnae 70,1%). Von den 25 bisher untersuchten Patienten (15 Frauen, 10 Männer; Durchschnittsalter: 55,3 Jahre; NU nach: 14 Monaten) waren 32% Typ A-, 20% Typ B- u. 48% Typ C-Frakturen. Die Greifkraft betrug 87,7 % und das Bewegungsausmaß 83,6 % im Vergleich zur Gegenseite. Der durchschnittliche standardisierte DASH-Score betrug 22,6 Punkte (0: optimale Funktion). Bei den mit volarer Platte stabilisierten C-Frakturen (9 der nachuntersuchten Patienten) fand sich ein DASH-Score von 41 Punkten. Die Greifkraft betrug 67,5% und das Bewegungsausmaß 79,6% im Vergleich zur Gegenseite. Bisher konnte weder bei der konventionellen, noch der winkelstabilen Plattenosteosynthese ein radiologischer Korrekturverlust nachgewiesen werden. Bei den Frakturen ohne lokale Begleitverletzungen waren Greifkraft (91% vs. 79,8%), Bewegungsausmaß (89,5% vs. 83,4%) und DASH-Score (16,8 vs. 26,1) besser als bei den Frakturen mit Begleitverletzungen. Schlussfolgerung Bei korrekter Reposition und Stabilisierung, wird der Outcome nach distaler Radiusfraktur neben dem Frakturtyp wesentlich durch die Begleitverletzung mitbestimmt. Daraus resultiert dass eine Verbesserung nur durch eine Optimierung der Therapie der Begleitverletzungen erreichbar ist.
Only a few Methyl-[11C]-l-methionine (MET) positron emission tomography (PET) studies have focused on children and young adults with brain neoplasm. Due to radiation exposure, long scan acquisition time, and the need for sedation in young children MET-PET studies should be restricted to this group of patients when a decision for further therapy is not possible from routine diagnostic procedures alone, e.g., structural imaging. We investigated the diagnostic accuracy of MET-PET for the differentiation between tumorous and non-tumorous lesions in this group of patients. Forty eight MET-PET scans from 39 patients aged from 2 to 21 years (mean 15 ± 5.0 years) were analyzed. The MET tumor-uptake relative to a corresponding control region was calculated. A receiver operating characteristic (ROC) was performed to determine the MET-uptake value that best distinguishes tumorous from non-tumorous brain lesions. A differentiation between tumorous (n = 39) and non-tumorous brain lesions (n = 9) was possible at a threshold of 1.48 of relative MET-uptake with a sensitivity of 83% and a specificity of 92%, respectively. A differentiation between high grade malignant lesions (mean MET-uptake = 2.00 ± 0.46) and low grade tumors (mean MET-uptake = 1.84 ± 0.31) was not possible. There was a significant difference in MET-uptake between the histologically homogeneous subgroups of astrocytoma WHO grade II and anaplastic astrocytoma WHO grade III (P = 0.02). MET-PET might be a useful tool to differentiate tumorous from non-tumorous lesions in children and young adults when a decision for further therapy is difficult or impossible from routine structural imaging procedures alone. Keywords Brain tumor - Children - PET - Methionine - Molecular imaging
Background: The alpha7 nicotinic acetylcholine receptor (Chrna7) plays an essential anti-inflammatory role in immune homeostasis and was recently found on mast cells (MC). Psychosocial stress can trigger MC hyperactivation and increases pro-inflammatory cytokines in target tissues such as the skin. If the cholinergic system (CS) and Chrna7 ligands play a role in these cascades is largely unknown. Objective: To elucidate the role of the CS in the response to psychosocial stress using a mouse-model for stress-triggered cutaneous inflammatory circuits. Methods: Key CS markers (ACh, Ch, SLURP-1, SLURP-2, Lynx1, Chrm3, Chrna7, Chrna9, ChAT, VAChT, Oct3, AChE, and BChE) in skin and its MC (sMC), MC activation, immune parameters (TNFα, IL1β, IL10, TGFβ, HIF1α, and STAT3) and oxidative stress were analyzed in skin from 24 h noise-stressed mice and in cultured MC (cMC) from C57BL/6 or Chrna7-Knockout mice. Results: First, Chrna7 and SLURP-1 mRNA were exclusively upregulated in stressed skin. Second, histomorphometry located Chrna7 and SLURP-1 in nerves and sMC and demonstrated upregulated contacts and increased Chrna7+ sMC in stressed skin, while 5 ng/mL SLURP-1 degranulated cMC. Third, IL1β+ sMC were high in stressed skin, and while SLURP-1 alone had no significant effect on cMC cytokines, it upregulated IL1β in cMC from Chrna7-KO and in IL1β-treated wildtype cMC. In addition, HIF1α+ sMC were high in stressed skin and Chrna7-agonist AR-R 17779 induced ROS in cMC while SLURP-1 upregulated TNFα and IL1β in cMC when HIF1α was blocked. Conclusions: These data infer that the CS plays a role in the regulation of stress-sensitive inflammatory responses but may have a surprising pro-inflammatory effect in healthy skin, driving IL1β expression if SLURP-1 is involved.