Muon identification in the Belle experiment at KEKB Abashian, A; Abe, K; Abe, K ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2002, Letnik:
491, Številka:
1-2
Journal Article
Recenzirano
Odprti dostop
This paper describes the muon identification method and its performance in the Belle experiment at KEKB. Muon and hadron likelihood are calculated for each track using its range and transverse ...scattering in the KL-and-muon detector (KLM). We apply a cut on the normalized muon likelihood Lμ to identify the track as a muon. Above the detection threshold of 0.6GeV/c, the measured muon detection efficiency and pion fake rate are approximately constant for momenta greater than 1.0 and 1.5GeV/c, respectively. Between 1.0 and 3.0GeV/c, the averaged muon detection efficiency is 89% and the pion fake rate per track is 1.4% over the KLM acceptance, using the standard selection criterion Lμ>0.9.
This study sought to determine the effective concentration for 50% of the attempts to secure laryngeal mask insertion (predicted EC50LMA) of propofol using a target-controlled infusion (Diprifusor™) ...and investigated whether fentanyl influenced these required concentrations, respiratory rate (RR) and bispectral index (BIS).
Sixty-four elective unpremedicated patients were randomly assigned to four groups (n = 16 for each group) and given saline (control) or fentanyl 0.5, 1 or 2 μg kg−1. Propofol target concentration was determined by a modification of Dixon's up-and-down method. Laryngeal mask airway insertion was attempted without neuromuscular blocking drugs after equilibration had been established for >10 min. Movement was defined as presence of bucking or gross purposeful muscular movement within 1 min after insertion. EC50LMA values were obtained by calculating the mean of 16 patients in each group.
Predicted EC50LMA of the control, fentanyl 0.5, 1 and 2 μg kg−1 groups were 3.25 (0.20), 2.06 (0.55), 1.69 (0.38) and 1.50 (0.54) μg ml−1 respectively; those of all fentanyl groups were significantly lower than that of control. RR was decreased in relation to the fentanyl dose up to 1 μg kg−1. BIS values after fentanyl 1 and 2 μg kg−1 were significantly greater than in the control and 0.5 μg kg−1 groups.
A fentanyl dose of 0.5 μg kg−1 is sufficient to decrease predicted EC50LMA with minimum respiratory depression and without a high BIS value.
Summary
This study sought to determine the predicted Cp50 of propofol required for laryngeal mask airway insertion (Cp50LMA) and to investigate whether nitrous oxide reduces these required ...concentrations. Using target‐controlled infusion and incorporating the standard Diprifusor™ pharmacokinetic model, 46 unpremedicated patients were randomly assigned to one of two groups. The patients received either 40% oxygen in air (control group: n = 23), or 60% nitrous oxide in oxygen (nitrous oxide group: n = 23). The target concentration for each patient was determined using the up and down method. Following equilibration between the predetermined blood and effect site concentrations, had been established for > 10 min, laryngeal mask airway insertion was attempted without neuromuscular relaxants. The data were analysed using a probit analysis to obtain Cp50LMA levels. The values for Cp50LMA were 3.24 µg.ml−1 in the control group and 1.93 µg.ml−1 in the nitrous oxide group.
Background Oocyte (egg) retrieval for in-vitro fertilization is a relatively short procedure, usually performed as an outpatient. Propofol is a suitable anesthetic agent. Target-controlled infusion ...is a recently developed system that aids rapid recovery from propofol anesthesia. This study sought to determine the target concentration of propofol required to prevent movement in 50% (Cp50) and 95% (Cp95) of women during oocyte retrieval, and investigated whether supplemental nitrous oxide (N2 O) modified the Cp50 and Cp95. Methods Forty-seven women scheduled for oocyte retrieval were randomly selected to receive either O2 -air mixture (control group; n = 23) or 50% O2 -N2 O mixture (Nitrous oxide group; n = 24). Propofol was infused using a target-controlled infusion system with the concentration determined by up-down sequential allocation using 0.5 μg/mL step size. Transvaginal oocyte retrieval was performed after reaching target blood concentration. Patient responses to oocyte retrieval were noted as either no movement or movement. Results Using target-controlled infusion the Cp50 was 4.1 μg/mL in the control group and 3.3 μg/mL in the nitrous oxide group. Calculated Cp95 values were 4.0 μg/mL and 5.1 μg/mL with and without 50% nitrous oxide respectively. Conclusions The Cp50 value for target-controlled infusion propofol during oocyte retrieval was significantly reduced by a factor of 1.24 (95% CI 1.07-1.44) with the use of 50% nitrous oxide.
The author experienced ten cases of anesthesia in a children's hospital in Nepal. Eight cases were pediatric surgeries and two cases were gynecological procedures. Halothane or intravenous ketamine ...anesthesia was performed in pediatric cases. Regional block or intravenous ketamine anesthesia was performed in gynecological cases. Oxygen supply stopped during anesthesia in one case, and patient was resuscitated by ambu-bag with room air. Electricity was interrupted in one case, and operation was continued with only one battery light. There is no mechanical ventilator nor nitrous oxygen in the hospital. Air conditioning was not in the operating room although the hospital was situated in the subtropical area and room temperature reached up to 40 degrees. Electrocardiogram and suction machines were present, but they were out of order. The anesthetic technique required in the developing countries is not so simple. Especially for young doctors trained among so many sophisticated monitors, anesthesia in the developing countries is not only an experience of volunteer, but provides effective training of pediatric anesthesia for strengthening their sense and skills.
Development of instrumentation for medical diagnosis and bioscreening based on biological magnetic labeling and detection of superparamagnetic particles is an active, multidisciplinary field of ...research. The scalability, high sensitivity, and compatibility with semiconductor integrated circuits (ICs) makes thin film micro-Hall sensors a practical choice of technology for the detection of magnetic particles. We describe the results of our systematic study on the fabrication of high-sensitivity micro-Hall devices using InSb, InAs, GaN, and bismuth thin films for detection of superparamagnetic particles coated with biological molecules. Sensor fabrication, scalability, magnetic-field sensitivity, and biological functionalization are discussed.
We evaluated the efficacy of clonidine given orally preoperatively for preventing postoperative vomiting (POV) in children undergoing propofol-nitrous oxide anaesthesia for strabismus surgery. Sixty ...children, ASA physical status I, aged 2-12 years, received diazepam, 0.4 mg x kg(-1) or clonidine, 4 microg x kg(-1) (n=30 each) orally, in a randomized double-blind manner. These drugs were given 105 min before an inhalational induction of anaesthesia. A complete response, defined as no POV and no need for rescue antiemetic medication, during 0-24 h after anaesthesia was 67% with diazepam and 93% with clonidine, respectively (P=0.024). No clinically adverse event was observed in any of the groups. In summary, pretreatment with oral clonidine enhances the antiemetic efficacy of propofol for the prevention of POV after paediatric strabismus surgery.
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