9,042 research outputs found
Beam profile measurements at 40 MHz in the PS to SPS transfer channel
Bunch to bunch beam profile measurements provide a valuable tool to control the injection lines to the SPS. A fast profile monitor based on a 2.5 ”m Mylar coated with Aluminium Optical Transition Radiation (OTR) radiator, has been developed, installed and tested in the transfer line between the PS and SPS. The OTR beam image is focused onto a fast Linear Multianode Photo Multiplier Tube and the associated electronics sample and store profiles every 25 ns. The paper describes the detector design, the electronic processing, and presents the results of different measurements made with bunches of 109-1011 protons at 26 GeV, and bunches of 106 Pb82 ions at 5.11 GeV/u
Did men of taste and civilization save the stage? Theatre-going in Rotterdam, 1860-1916. A statistical analysis of ticket sales
This essay deals with Dutch theater history of the second half of the 19th century (1860â1916). It statistically tests, whether the dominant opinion in Dutch theater writing, that after 1870 the stage recovered from a half century of decline, due to a renewed interest in it by the city elite, occupying the first ranks with a taste for civilized modern drama, and that, hence, a sharp cleft became visible between lower-rank tastes and upper-rank tastes. We test the tenability of this position on the basis of the Rotterdam Grand Theater archives, which contain ticket sales per rank per performance from 1776 till 1916, and the play bills of the performances. We analyze aggregated behavior of an anonymous theater consumers subdivided into price classes, hypothesizing that differences in attendance to high and low quality plays (as the critics judged them) over the different ranks, might reveal class-based divisions of taste. A long-memory time series analysis confirms that there is a significant gradual change of quality in the theater during the period 1860â1881, but this change is hardly rank- (and by implication likely class-) based. A second time series analysis, analyzing the impact of the repertoire and companies controlled for season and dynamics of the time series over the years 1860â1887 and 1887â1916, hardly sustains the narrative of recovery for most products as related to ranks. Only in a few telling instances, there was a clear opposition between low-rank tastes and upper-rank tastes. Hence, the recovery thesis must on the whole be rejected. This research will be followed-up by a prosopographical analysis of season-ticket and coupon holders in the Rotterdam theaters from 1773â1916, in which more detailed information on the social backgrounds and particularly on social class division of not anonymous theater audiences in `the long 19th century' is central
Association between congenital toxoplasmosis and preterm birth, low birthweight and small for gestational age birth.
OBJECTIVE: To determine the association between congenital toxoplasmosis and preterm birth, low birthweight and small for gestational age birth. DESIGN: Multicentre prospective cohort study. SETTING: Ten European centres offering prenatal screening for toxoplasmosis. POPULATION: Deliveries after 23 weeks of gestation in 386 women with singleton pregnancies who seroconverted to toxoplasma infection before 20 weeks of gestation. Deliveries after 36 weeks in 234 women who seroconverted at 20 weeks or later, and tested positive before 37 weeks. METHODS: Comparison of infected and uninfected births, adjusted for parity and country of birth. MAIN OUTCOME MEASURES: Differences in gestational age at birth, birthweight and birthweight centile. RESULTS: Infected babies were born or delivered earlier than uninfected babies: the mean difference for seroconverters before 20 weeks was -5.4 days (95% CI: -1.4, -9.4), and at 20 weeks or more, -2.6 days (95% CI: -0.5, -4.7). Congenital infection was associated with an increased risk of preterm delivery when seroconversion occurred before 20 weeks (OR 4.71; 95% CI: 2.03, 10.9). No significant differences were detected for birthweight or birthweight centile. CONCLUSION: Babies with congenital toxoplasmosis were born earlier than uninfected babies but the mechanism leading to shorter length of gestation is unknown. Congenital infection could precipitate early delivery or prompt caesarean section or induction of delivery. We found no evidence for a significant association between congenital toxoplasmosis and reduced birthweight or small for gestational age birth
Utility of the Cortical Thickness of the Distal Radius as a Predictor of Distal-Radius Bone Density
Background: Bone density is an important factor in the management of fractures of the distal radius.
Objectives: The aim of this study was to establish whether standard anteroposterior (AP) radiographs would provide the attending physician with a prediction of bone density.
Patients and Methods: Six pairs of human cadaveric radii were harvested. The mean donor age was 74 years. Standardized AP radiographs were taken of the radii. The outside diameter and the inside diameter of the cortical shell at the metaphyseal / diaphyseal junction were measured and their ratio was calculated. Dual-energy x-ray absorptiometry (DXA) was used to obtain the bone mineral density (BMD) of the distal parts of the radii. The correlation of the BMD values with these ratios was studied.
Results: The mean BMD was 0.559 (SD = 0.236) g / cm2. The mean outside diameter/inside diameter ratio was 1.24 (SD = 0.013); the ratio significantly correlated with the total BMD (P = 0.001; R2 = 0.710). In the BMD subregions, the correlation was also significant.
Conclusions: The outside diameter/inside diameter ratio at the metaphyseal/diaphyseal junction of the distal radius on AP radiographs is suitable for use as a predictor of distal-radius bone density. Further studies should be performed, and clinical utility evaluated
Three-mode opto-acoustic parametric interactions with coupled cavity
We theoretically analyze three-mode opto-acoustic parametric interactions in
a coupled Fabry-Perot cavity, where one acoustic mode interacts with two
optical modes. We show explicitly that extra degrees of freedom in a coupled
cavity allow explorations of both parametric instability and cooling regimes
with high parametric gain in a single table top experiment. This work can
motivate experimental realizations of the three-mode parametric instability
which might be an issue in next-generation gravitational-wave detectors with
high optical-power cavities, helping in the development of better models, and
in developing techniques for controls. In addition, we show that the same
scheme can be implemented in the resolved-sideband acoustic-mode cooling.Comment: 15 pages, 7 figure
Beam Scraping for LHC Injection
Operation of the LHC will require injection of very high intensity beams from the SPS to the LHC. Fast scrapers have been installed and will be used in the SPS to detect and remove any existing halo before beams are extracted, to minimize the probability for quenching of superconducting magnets at injection in the LHC. We briefly review the functionality of the scraper system and report about measurements that have recently been performed in the SPS on halo scraping and re-population of tails
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