6,415 research outputs found
Ageing test of the ATLAS RPCs at X5-GIF
An ageing test of three ATLAS production RPC stations is in course at X5-GIF,
the CERN irradiation facility. The chamber efficiencies are monitored using
cosmic rays triggered by a scintillator hodoscope. Higher statistics
measurements are made when the X5 muon beam is available. We report here the
measurements of the efficiency versus operating voltage at different source
intensities, up to a maximum counting rate of about 700Hz/cm^2. We describe the
performance of the chambers during the test up to an overall ageing of 4 ATLAS
equivalent years corresponding to an integrated charge of 0.12C/cm^2, including
a safety factor of 5.Comment: 4 pages. Presented at the VII Workshop on Resistive Plate Chambers
and Related Detectors; Clermont-Ferrand October 20th-22nd, 200
LH supplementation of ovarian stimulation protocols influences follicular fluid steroid composition contributing to the improvement of ovarian response in poor responder women.
Abstract In this prospective study, we evaluated the steroid levels in 111 follicular fluids (FF) collected from 13 women stimulated with FSH monotherapy and 205 FF collected from 28 women stimulated with FSH + LH because of a previous history of hypo-responsiveness to FSH. Steroid levels were measured by HPLC/MS–MS and related to ovarian stimulation protocol, oocyte maturity, fertilization and quality of blastocysts, after individually tracking the fate of all retrieved oocytes. 17-Hydroxy-Progesterone, Androstenedione, Estradiol and Estrone were significantly higher in the FSH + LH protocol. Progesterone, 17-Hydroxy-Progesterone and Estradiol were more expressed in FF yielding a mature oocyte (p < 0.01) in the FSH + LH protocol. FF Progesterone concentration was correlated with the rate of normal fertilization in the FSH protocol. None of the FF steroids measured were associated with blastocyst quality and achievement of pregnancy. Our results indicate that LH supplementation in hypo-responsive women modifies ovarian steroid production, mimicking physiological production better and likely contributing to an improved ovarian response. Employing a correct methodological procedure to evaluate the relationship between FF steroid hormones and assisted reproduction outcomes, our study reveals that some steroids in single follicles may be helpful in predicting oocyte maturity and fertilization
Sexual Intercourse for Induction of Spontaneous Onset of Labor: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
INTRODUCTION:
Sexual intercourse during pregnancy is commonly believed to trigger the onset of contractions and, therefore, labor. However, in low-risk pregnancies, there is neither association with preterm birth, premature rupture of membranes, or low birth weight, nor with spontaneous onset of labor at term.
AIM:
To evaluate the effectiveness of sexual intercourse for spontaneous onset of labor at term in singleton pregnancies.
METHODS:
The systematic search was conducted using electronic databases from inception of each database to June 2019. Review of articles also included the abstracts of all references retrieved from the search. Inclusion criteria were randomized controlled trials comparing sexual intercourse in singleton low-risk pregnancies at term with controls (either reduced number of coitus or no coitus) for spontaneous onset of labor. Estimates were pooled using random-effects meta-analysis.
MAIN OUTCOME MEASURES:
The primary outcome was the incidence of spontaneous onset of labor. The summary measures were reported as summary relative risk with 95% CI using the random-effects model of DerSimonian and Laird.
RESULTS:
Data extracted from 3 trials, including 1,483 women with singleton pregnancy at term and cephalic presentation, were analyzed. Women who were randomized in the sexual intercourse group had similar incidence of spontaneous onset of labor compared with control subjects (0.82% vs 0.80%; relative risk 1.02, 95% CI 0.98-1.07).
CLINICAL IMPLICATION:
Sexual intercourse should not be restricted in low-risk term pregnancies. Further studies are needed to properly evaluate the impact of orgasm, penetration, condom use, frequency of intercourse and other factors on induction of labor at term.
STRENGTH & LIMITATIONS:
Our study has several strengths. The three included trials had low risk of allocation bias; intention-to-treat analysis was used; this is the first meta-analysis on this issue so far. Limitations mainly depend on the design of the included studies. Firstly, compliance to the protocol relied on self-reporting by patients; in addition, not all the features of sexual intercourse could be adequately assessed (orgasm, nipple stimulation, sexual positions, etc.).
CONCLUSION:
In women with singleton, cephalic, low-risk pregnancies, sexual intercourse at term does not significantly increase the incidence of spontaneous onset of labor
Search for Branons at LEP
We search, in the context of extra-dimension scenarios, for the possible
existence of brane fluctuations, called branons. Events with a single photon or
a single Z-boson and missing energy and momentum collected with the L3 detector
in e^+ e^- collisions at centre-of-mass energies sqrt{s}=189-209$ GeV are
analysed. No excess over the Standard Model expectations is found and a lower
limit at 95% confidence level of 103 GeV is derived for the mass of branons,
for a scenario with small brane tensions. Alternatively, under the assumption
of a light branon, brane tensions below 180 GeV are excluded
Study of Spin and Decay-Plane Correlations of W Bosons in the e+e- -> W+W- Process at LEP
Data collected at LEP at centre-of-mass energies \sqrt(s) = 189 - 209 GeV are
used to study correlations of the spin of W bosons using e+e- -> W+W- -> lnqq~
events. Spin correlations are favoured by data, and found to agree with the
Standard Model predictions. In addition, correlations between the W-boson decay
planes are studied in e+e- -> W+W- -> lnqq~ and e+e- -> W+W- -> qq~qq~ events.
Decay-plane correlations, consistent with zero and with the Standard Model
predictions, are measured
Ultrarelativistic sources in nonlinear electrodynamics
The fields of rapidly moving sources are studied within nonlinear
electrodynamics by boosting the fields of sources at rest. As a consequence of
the ultrarelativistic limit the delta-like electromagnetic shock waves are
found. The character of the field within the shock depends on the theory of
nonlinear electrodynamics considered. In particular, we obtain the field of an
ultrarelativistic charge in the Born-Infeld theory.Comment: 10 pages, 3 figure
Measurement of the Cross Section for Open-Beauty Production in Photon-Photon Collisions at LEP
The cross section for open-beauty production in photon-photon collisions is
measured using the whole high-energy and high-luminosity data sample collected
by the L3 detector at LEP. This corresponds to 627/pb of integrated luminosity
for electron-positron centre-of-mass energies from 189GeV to 209GeV. Events
containing b quarks are identified through their semi-leptonic decay into
electrons or muons. The e+e- -> e+e-b b~X cross section is measured within our
fiducial volume and then extrapolated to the full phase space. These results
are found to be in significant excess with respect to Monte Carlo predictions
and next-to-leading order QCD calculations
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