Ultrasonic assessment of cesarean section scar to vesicovaginal fold distance: an instrument to estimate pre-labor uterine rupture risk

Background: The number of Cesarean sections (CS) is growing worldwide, intensifying the risk of complications in subsequent pregnancies and leading to increased maternal and fetal morbidity and mortality. In particular, the literature shows a higher risk of uterine rupture (UR) in subsequent pregnancy with trial of labor after cesarean section (TOLAC) Furthermore, there are few data about pre-labor UR in scarred uteri. Objective: Since the key factor for management is timing, the aim of this study was to evaluate the accuracy of prenatal ultrasound (US) of scars in the early determining of pre-labor UR risk in women with a previous CS during their subsequent pregnancy Methods: From April 2014 to November 2018 a retrospective analysis was performed in order to evaluate the scar to vesicovaginal fold (VVF) distance in three patients with pre-labor UR and in 60 cases of the control group. Results: The periconceptional CS scar-VVF distance in the three UR cases resulted significantly increased compared to the controls (23.7 ± 3.5 mm vs 2.3 ± 2.7 mm, p < 005); moreover, a time interval of less than 18 months and a previous pre-labor preterm CS were found as known risk factors. Conclusion: In this study, a higher uterine incision due to placenta previa or isthmic myoma seems to be correlated with a major risk of UR. Therefore, periconceptional US examination of CS-VVF distance, (which represents the level of the previous CS), seems to be a useful predictive factor of pre-labor UR in subsequent pregnancies

Diagnosis of major heart defects by routine first-trimester ultrasound examination: association with high nuchal translucency, tricuspid regurgitation and abnormal flow in the ductus venosus

Objective: To examine the association between fetal major heart defects and high nuchal translucency thickness (NT), tricuspid regurgitation and abnormal flow in the ductus venosus in a large population of singleton pregnancies undergoing a routine ultrasound examination at 11-13 weeks’ gestation. Methods: This was a retrospective study of prospectively collected data from singleton pregnancies attending for a routine ultrasound scan at 11-13 weeks’ gestation which included examination of fetal anatomy, measurement of NT, and assessment of blood flow across the tricuspid valve and in the ductus venosus according to a standardized protocol. The incidence of fetal NT ≥95th and NT ≥99th percentile, tricuspid regurgitation and reversed a-wave in the ductus venosus in fetuses with and without major heart defects was determined and the performance of each marker and their combination in the detection of major heart defects was calculated. Results: The study population of 93,209 pregnancies with no apparent chromosomal abnormality included 211 (0.23%) with major heart defects and 92,998 morphologically normal neonates. In 113 (53.6%) of the major heart defects the diagnosis was made at the 11-13 weeks scan, in 82 (38.9%) at the 18-24 weeks scan, in 10 (4.7%) at the third-trimester scan and in 6 (2.8%) postnatally. At the 11-13 weeks scan we diagnosed all cases of tricuspid or pulmonary atresia and polyvalvular dysplasia, >90% of cases of hypoplastic left heart syndrome or atrioventricular septal defect, about 60% of complex heart defects and left atrial isomerism (interrupted inferior vena cava with normal intracardiac anatomy), 30-40% of tetralogy of Fallot and arch abnormalities, 25% of tricuspid valve abnormalities, about 15% of transposition of great arteries, but none of aortic or pulmonary stenosis and common arterial trunk. Fetal NT ≥95th percentile, NT ≥99th percentile, tricuspid regurgitation, or abnormal ductus venosus flow was observed in 77 (36.5%), 45 (21.3%), 61 (28.9%), and 58 (27.5%) of the fetuses with major heart defects, respectively, and in 5,678 (6.1%), 857 (0.9%), 1,136 (1.2%), and 1,644 (1.8%) of those without heart defects. Any one of NT ≥95th, tricuspid regurgitation or abnormal flow in the ductus venosus was found in 117 (55.5%, 95% CI 48.5–62.3%) of the fetuses with heart defects and in 8,166 (8.8%, 95% CI 8.6-9.0%) of those without heart defects. Any one of NT ≥99th percentile and the other two markers was found in 99 of the fetuses with heart defects (46.9%, 95% CI 40.0-53.9%) and in 3,517 of those without heart defects (3.8%, 95% CI 3.7-3.9%). Conclusion: At 11-13 weeks’ gestation measurement of fetal NT and assessment of flow across the tricuspid valve and in the ductus venosus can lead to the early diagnosis of major heart defects

Atazanavir and darunavir in pregnant women with HIV: Evaluation of laboratory and clinical outcomes from an observational national study

Background: Atazanavir and darunavir represent the main HIV PIs recommended in pregnancy, but comparativedata in pregnant women are limited.We assessed the safety and activity profile of these two drugs in pregnancyusing data from a national observational study.Methods: Women with atazanavir or darunavir exposure in pregnancy were evaluated for laboratory measuresand main pregnancy outcomes (e.g. preterm delivery, low birthweight, non-elective caesarean section and neonatalgestational age-adjusted birthweight Z-score).Results: Final analysis included 500 pregnancies with either atazanavir (n"409) or darunavir (n"91) exposure.No differences in pregnancy outcomes, weight gain in pregnancy, drug discontinuations, undetectable HIV-RNA,haemoglobin, ALT, total cholesterol, HDL cholesterol and LDL cholesterol were observed between the twogroups. At third trimester, exposure to darunavir was associated with higher levels of plasma triglycerides(median 235.5 versus 179 mg/dL; P"0.032) and a higher total cholesterol/HDL cholesterol ratio (median 4.03versus 3.27; P"0.028) and exposure to atazanavir was associated with higher levels of plasma bilirubin (1.54versus 0.32 mg/dL; P<0.001).Conclusions: In this observational study, the two main HIV PIs currently recommended by perinatal guidelinesshowed similar safety and activity in pregnancy, with no evidence of differences between the two drugs in termsof main pregnancy outcomes. Based on the minor differences observed in laboratory measures, prescribingphysicians might prefer either drug in some particular situations where the different impacts of treatment onlipid profile and bilirubin may have clinical relevance

Track reconstruction and matching between emulsion and silicon pixel detectors for the SHiP-charm experiment

In July 2018 an optimization run for the proposed charm cross section measurement for SHiP was performed at the CERN SPS. A heavy, moving target instrumented with nuclear emulsion films followed by a silicon pixel tracker was installed in front of the Goliath magnet at the H4 proton beam-line. Behind the magnet, scintillating-fibre, drift-tube and RPC detectors were placed. The purpose of this run was to validate the measurement's feasibility, to develop the required analysis tools and fine-tune the detector layout. In this paper, we present the track reconstruction in the pixel tracker and the track matching with the moving emulsion detector. The pixel detector performed as expected and it is shown that, after proper alignment, a vertex matching rate of 87% is achieved.Peer Reviewe

SND@LHC: The Scattering and Neutrino Detector at the LHC

SND@LHC is a compact and stand-alone experiment designed to perform measurements with neutrinos produced at the LHC in the pseudo-rapidity region of ${7.2 < \eta < 8.4}$. The experiment is located 480 m downstream of the ATLAS interaction point, in the TI18 tunnel. The detector is composed of a hybrid system based on an 830 kg target made of tungsten plates, interleaved with emulsion and electronic trackers, also acting as an electromagnetic calorimeter, and followed by a hadronic calorimeter and a muon identification system. The detector is able to distinguish interactions of all three neutrino flavours, which allows probing the physics of heavy flavour production at the LHC in the very forward region. This region is of particular interest for future circular colliders and for very high energy astrophysical neutrino experiments. The detector is also able to search for the scattering of Feebly Interacting Particles. In its first phase, the detector will operate throughout LHC Run 3 and collect a total of 250 $\text{fb}^{-1}$

The SHiP experiment at the proposed CERN SPS Beam Dump Facility

The Search for Hidden Particles (SHiP) Collaboration has proposed a general-purpose experimental facility operating in beam-dump mode at the CERN SPS accelerator to search for light, feebly interacting particles. In the baseline configuration, the SHiP experiment incorporates two complementary detectors. The upstream detector is designed for recoil signatures of light dark matter (LDM) scattering and for neutrino physics, in particular with tau neutrinos. It consists of a spectrometer magnet housing a layered detector system with high-density LDM/neutrino target plates, emulsion-film technology and electronic high-precision tracking. The total detector target mass amounts to about eight tonnes. The downstream detector system aims at measuring visible decays of feebly interacting particles to both fully reconstructed final states and to partially reconstructed final states with neutrinos, in a nearly background-free environment. The detector consists of a 50 m long decay volume under vacuum followed by a spectrometer and particle identification system with a rectangular acceptance of 5 m in width and 10 m in height. Using the high-intensity beam of 400 GeV protons, the experiment aims at profiting from the 4 x 10(19) protons per year that are currently unexploited at the SPS, over a period of 5-10 years. This allows probing dark photons, dark scalars and pseudo-scalars, and heavy neutral leptons with GeV-scale masses in the direct searches at sensitivities that largely exceed those of existing and projected experiments. The sensitivity to light dark matter through scattering reaches well below the dark matter relic density limits in the range from a few MeV/c(2) up to 100 MeV-scale masses, and it will be possible to study tau neutrino interactions with unprecedented statistics. This paper describes the SHiP experiment baseline setup and the detector systems, together with performance results from prototypes in test beams, as it was prepared for the 2020 Update of the European Strategy for Particle Physics. The expected detector performance from simulation is summarised at the end

Track reconstruction and matching between emulsion and silicon pixel detectors for the SHiP-charm experiment

In July 2018 an optimization run for the proposed charm cross section measurement for SHiP was performed at the CERN SPS. A heavy, moving target instrumented with nuclear emulsion films followed by a silicon pixel tracker was installed in front of the Goliath magnet at the H4 proton beam-line. Behind the magnet, scintillating-fibre, drift-tube and RPC detectors were placed. The purpose of this run was to validate the measurement's feasibility, to develop the required analysis tools and fine-tune the detector layout. In this paper, we present the track reconstruction in the pixel tracker and the track matching with the moving emulsion detector. The pixel detector performed as expected and it is shown that, after proper alignment, a vertex matching rate of 87% is achieved

Measurement of the muon flux from 400 GeV/c protons interacting in a thick molybdenum/tungsten target

The SHiP experiment is proposed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. About 1011 muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400 GeV/c proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a 3-week period a dataset for analysis corresponding to (3.27±0.07) × 1011 protons on target was recorded. This amounts to approximatively 1% of a SHiP spill

Fast simulation of muons produced at the SHiP experiment using generative adversarial networks

This paper presents a fast approach to simulating muons produced in interactions of the SPS proton beams with the target of the SHiP experiment. The SHiP experiment will be able to search for new long-lived particles produced in a 400 GeV/c SPS proton beam dump and which travel distances between fifty metres and tens of kilometers. The SHiP detector needs to operate under ultra-low background conditions and requires large simulated samples of muon induced background processes. Through the use of Generative Adversarial Networks it is possible to emulate the simulation of the interaction of 400 GeV/c proton beams with the SHiP target, an otherwise computationally intensive process. For the simulation requirements of the SHiP experiment, generative networks are capable of approximating the full simulation of the dense fixed target, offering a speed increase by a factor of Script O(106). To evaluate the performance of such an approach, comparisons of the distributions of reconstructed muon momenta in SHiP's spectrometer between samples using the full simulation and samples produced through generative models are presented. The methods discussed in this paper can be generalised and applied to modelling any non-discrete multi-dimensional distribution

The experimental facility for the Search for Hidden Particles at the CERN SPS

The International School for Advanced Studies (SISSA) logo The International School for Advanced Studies (SISSA) logo The following article is OPEN ACCESS The experimental facility for the Search for Hidden Particles at the CERN SPS C. Ahdida44, R. Albanese14,a, A. Alexandrov14, A. Anokhina39, S. Aoki18, G. Arduini44, E. Atkin38, N. Azorskiy29, J.J. Back54, A. Bagulya32Show full author list Published 25 March 2019 • © 2019 CERN Journal of Instrumentation, Volume 14, March 2019 Download Article PDF References Download PDF 543 Total downloads 7 7 total citations on Dimensions. Article has an altmetric score of 1 Turn on MathJax Share this article Share this content via email Share on Facebook Share on Twitter Share on Google+ Share on Mendeley Article information Abstract The Search for Hidden Particles (SHiP) Collaboration has shown that the CERN SPS accelerator with its 400 GeV/c proton beam offers a unique opportunity to explore the Hidden Sector [1–3]. The proposed experiment is an intensity frontier experiment which is capable of searching for hidden particles through both visible decays and through scattering signatures from recoil of electrons or nuclei. The high-intensity experimental facility developed by the SHiP Collaboration is based on a number of key features and developments which provide the possibility of probing a large part of the parameter space for a wide range of models with light long-lived super-weakly interacting particles with masses up to Script O(10) GeV/c2 in an environment of extremely clean background conditions. This paper describes the proposal for the experimental facility together with the most important feasibility studies. The paper focuses on the challenging new ideas behind the beam extraction and beam delivery, the proton beam dump, and the suppression of beam-induced background