We have measured the cross section σ(e+e−→π+π−γ) at an energy W=mϕ=1.02 GeV with the KLOE detector at the electron–positron collider DAΦNE. From the dependence of the cross section on the invariant ...mass of the two-pion system, we extract σ(e+e−→π+π−) for the mass range 0.35<s<0.95 GeV2. From this result, we calculate the pion form factor and the hadronic contribution to the muon anomaly, aμ.
In an effort to make laparoscopic suturing more efficient, the V-Loc advanced wound closure device (Covidien, Mansfield, MA) has been produced. This device is a self-anchoring barbed suture that ...obviates the need for knot tying. The goal of this initial feasibility study was to investigate the use of the barbed suture in gastrointestinal enterotomy closure. A randomized study of 12 pigs comparing enterotomy closure with barbed versus a nonbarbed suture of similar tensile strength was performed. To this end, 25 mm enterotomies were made in the stomach (1 control, 1 treatment), jejunum (2 controls, 2 treatments), and descending colon (1 control, 1 treatment). Animals were killed at 3, 7, and 14 days postoperatively (4 each group) and their gastrointestinal tracts harvested; 6 of the 8 enterotomies from each pig underwent burst strength testing. The remaining 2 were fixed in formalin and sent for histological examination. All 12 pigs survived until they were killed without any major complications. Enterotomy closure with barbed suture revealed adhesion scores, burst strength pressures, and histology scores that were similar to those for the control. Jejunal closures resulted in 6 failures at 7 days (3 control, 3 barbed) and 4 failures at 14 days (2 control, 2 barbed). The barbed suture significantly reduced suturing time in the stomach, jejunum, and colon. The V-Loc wound closure device appears to offer comparable gastrointestinal closure to 3-0 Maxon while being significantly faster. Further studies with V-Loc are required to assess its use in laparoscopic surgery.
We have measured the ratio Rϕ=BR(ϕ→η′γ)/BR(ϕ→ηγ) by looking for the radiative decays ϕ→η′γ and ϕ→ηγ into the final states π+π−7γ and 7γ, respectively, in a sample of ∼1.4×109ϕ mesons produced at the ...Frascati ϕ factory. We obtain Rϕ=(4.77±0.09stat±0.19syst)×10−3, from which we derive BR(ϕ→η′γ)=(6.20±0.11stat±0.25syst)×10−5. Assuming the η′ has zero gluonium content, we extract the pseudoscalar mixing angle in the quark-flavor basis, φP=(41.4±0.3stat±0.7syst±0.6th)°. Combining the value of Rϕ with other constraints, we estimate the fractional gluonium content of the η′ to be Z2=0.14±0.04 and the mixing angle to be φP=(39.7±0.7)°.
The effect of RH-5992 (tebufenozide), a non-steroidal ecdysone agonist, on adult development of the spruce budworm,
Choristoneura fumiferana, was investigated by administering the compound ...intrahemocoelically to pupae on days 1–6 after pupal ecdysis. At concentrations of 200
ng/pupa there was significant mortality but at doses of 50–100
ng/pupa, the emerging adults displayed wing deformities which reduced their ability to mate and oviposit. Light microscopy of the pupal wings revealed that there was degeneration of the epithelial cells, reduction in the number of veins, precocious cuticle formation and inhibition of growth of normal wing scales. Injection of RH-5992 into pupae resulted in a dose dependent induction of mRNA for ecdysone-induced transcription factor,
Choristoneura hormone receptor 3 (CHR3). These results suggest that the pupae respond to RH-5992 in a manner similar to larvae. However, the effects are not expressed overtly and are camouflaged by the pharmacological effects.
RPCs will be used as trigger detectors in the barrel region of the Muon Spectrometer of the ATLAS experiment at LHC. The total number of RPC units to be installed is 1088, covering a total surface of ...about 3500m2. ATLAS RPCs work in avalanche mode with C2H2F4/C4H10/SF6 (94.7%/5%/0.3%) gas mixture. A cosmic ray test stand has been designed and built in Naples laboratories in order to carry out a complete test of the ATLAS RPC units. Since August 2002 about 300 units have been tested. A description of the test stand, test procedure and results are presented.
Our purpose was to determine the effects of the coculture of embryos on human granulosa cells (GCs) in patients in the first cycle of IVF-ET treatment and in patients with repeated implantation ...failures and to investigate the presence of specific proteins in a 48-hr GC conditioned medium and the GC ultrastructural characteristics.
Eighteen patients with tubal or idiopathic infertility were enrolled in this study: 7 patients (Trial 1) were in the first cycle of IVF-ET treatment and 11 patients (Trial 2) had repeated implantation failures (one to five). Embryos from each patient were cocultured randomly either on homologous granulosa cells or on a conventional culture medium.
At the end of the coculture period (day 5 or 6), 50% of the embryos (Trial 1) reached the blastocyst stage, with respect to 35% in Trial 2. The pregnancy rate per retrieval was 14.2 and 9%, respectively, in Trial 1 and in Trial 2. Many conditioned media showed proteins of 24-29 kDa. and some of them showed additional proteins of 90 kDa. The ultrastructural analysis of GCs showed healthy, metabolically active, protein-synthesizing, and mostly steroidogenic cells.
GC cultures improve embryo development but not pregnancy rates both in Trial 1 and in Trial 2.
Muon identification (MUID) and high-momentum measurement accuracy is crucial to fully exploit the physics potential that will be accessible with the ATLAS experiment at the LHC. The muon energy of ...physics interest ranges in a large interval from few GeV, where the b-physics studies dominate the physics program, up to the highest values that could indicate the presence of new physics. The muon detection system of the ATLAS detector is characterized by two high-precision tracking systems, namely the inner detector (ID) and the muon spectrometer, (MS) plus a thick calorimeter that ensures a safe hadron absorption filtering with high-purity muons with energy above 3 GeV. In order to combine the muon tracks reconstructed in the ID and the MS, a MUID object-oriented software package has been developed. The purpose of the MUID procedure is to associate tracks found in the MS with the corresponding ID track and calorimeter information in order to identify muons at their production vertex with optimum parameter resolution. The performance of these two combined systems has been evaluated with Monte Carlo studies using single muons of fixed-transverse momentum and with full physics events.
The tracking detector of the KLOE experiment Adinolfi, M; Ambrosino, F; Andryakov, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2002, Letnik:
488, Številka:
1
Journal Article
Recenzirano
The design and construction of the large Drift Chamber for the KLOE experiment at the Frascati φ-factory, DAΦNE, are described. The relevant aspects of the various elements of the detector are ...reviewed together with a description of the track reconstruction program and of the calibration procedures. The performance of the detector based on measurements with cosmic rays and with e
+e
− colliding beams during DAΦNE commissioning is presented.
PDF
