Path Simulations of the LINAC2 Transfer Line

The purpose of this work is to evaluate the transverse emittance growth in a beam line in presence of space charge, dispersion and energy spread. The Transfer Line of the Linac2 has been taken as an example, as measurement to confirm might be possible. In the original design, the dispersion has a very low value; the dispersion has been increased varying the quadrupoles between the bending magnets. Finally the bending magnets have been removed, nullifying the dispersion. In order to investigate the influence of the energy spread, the gap voltage and phase have been changed, observing the emittance growth after the BHZ30

End-to end simulations of LINAC4

Linac4 is a new H- linear accelerator presently studied at CERN. This machine consists of normal-conducting structures operating at 352.2 MHz and 704.4 MHz re-using the RF equipment from the decommissioned LEP collider. It consists of a 95 keV H- source, a 352 MHz RFQ bringing the energy the energy to 3 MeV, a Chopper line, a 352 MHz Drift Tube Linac bringing the energy to 40 MeV, a 352 MHz Coupled Cavity Drift Tube Linac bringing the energy to 90 MeV and a 704 MHz Side Coupled Linac bringing the energy to 160 MeV. Each section is designed and optimized as stand-alone machines for a good transmission and minimum possible emittance growth. End-to-end simulations starting from the RFQ have been carried out in order to validate and compare the multiparticle simulation codes PATH Manager and TRACEWIN used for beam dynamics calculations as well as to perform a global optimization of the structures in the context of a complex machine

Loss Control and Steering Strategy for the CERN LINAC4

A series of runs with the aim of defining alignment and gradient tolerances for the quadrupoles have been performed on the LINAC4 reference layout. The results, the implication on the machine layout and the correction schemes are reported in this paper

End-to-End Beam Dynamics for CERN LINAC4

LINAC 4 is a normal conducting H- linac which aims to intensify the proton flux available for the CERN accelerator complex. This injector is designed to accelerate a 65 mA beam of H- ions up to 160 MeV for injection into the CERN Proton Synchrotron Booster. The acceleration is done in three stages : up to 3 MeV with a Radio Frequency Quadrupole (the IPHI RFQ) operating at 352 MHz, then continued to 90 MeV with drift-tube structures at 352 MHz (conventional Alvarez and Cell Coupled Drift Tube Linac) and, finally with a Side Coupled Linac at 704 MHz. The accelerator is completed by a chopper line at 3 MeV and a transport and matching line to the PS booster. After the overall layout was determined based on general consideration of beam dynamics and RF, a global optimisation based on end-to-end simulation has refined some design choices. The results and lessons learned from the end-to-end simulations are reported in this paper

Circulating EGFL7 distinguishes between IUGR and PE: an observational case–control study

Isolated intrauterine growth restriction (IUGR) and preeclampsia (PE) share common placental pathogenesis. Differently from IUGR, PE is a systemic disorder which may also affect liver and brain. Early diagnosis of these conditions may optimize maternal and fetal management. Aim of this study was to assess whether Epidermal Growth Factor-Like domain 7 (EGFL7) dosage in maternal blood discriminates between isolated IUGR and PE. A total of 116 women were enrolled in this case-control study: 12 non-pregnant women, 34 healthy pregnant women, 34 women presenting with isolated IUGR and 36 presenting with PE. Levels of circulating EGFL7 and other known pro- and anti-angiogenic factors were measured by ELISA at different gestational ages (GA). Between 22-25 weeks of gestation, EGFL7 levels in early-onset PE (e-PE) plasma samples were significantly higher than those measured in controls or isolated IUGR samples (69.86 ± 6.17 vs. 19.8 ± 2.5 or 18.8 ± 2.8 µg/ml, respectively). Between 26-34 weeks, EGFL7 levels remained significantly higher in e-PE compared to IUGR. At term, circulating and placental EGFL7 levels were comparable between IUGR and late-onset PE (l-PE). In contrast, circulating levels of PlGF were decreased in both IUGR- and PE- complicated pregnancies, while levels of both sFLT-1 and sENDOGLIN were increased in both conditions. In conclusion, EGFL7 significantly discriminates between isolated IUGR and PE

Risk factors associated with severe perineal lacerations during vaginal delivery: a 10-year propensity score–matched observational study

From Elsevier via Jisc Publications RouterHistory: epub 2023-04-27, issued 2023-05-31Article version: VoRPublication status: PublishedValentina Laurita Longo - ORCID: 0000-0003-4071-9936 https://orcid.org/0000-0003-4071-9936Emmanuel Nene Odjidja - ORCID: 0000-0003-3502-5120 https://orcid.org/0000-0003-3502-5120BACKGROUND Severe perineal lacerations are rare obstetrical complications in high-income countries. However, the prevention of obstetric anal sphincter injuries is crucial because of their long-term consequences on a woman's digestive function, sexual-mental health, and well-being. The probability of obstetric anal sphincter injuries can be predicted by assessing antenatal and intrapartum risk factors. OBJECTIVE This study aimed to assess the incidence of obstetric anal sphincter injuries at a single institution for 10 years and to identify women more at risk by evaluating the relationship between antenatal and intrapartum risk factors and severe perineal tears. The main outcome measured in this study was the occurrence of obstetric anal sphincter injuries during vaginal delivery. STUDY DESIGN This was an observational retrospective cohort study conducted at a University Teaching Hospital in Italy. The study was conducted from 2009 to 2019 using a prospectively maintained database. The study cohort included all women with singleton pregnancy at term who delivered via vaginal delivery in cephalic presentation. Of note, data analysis was performed in 2 stages: a propensity score matching to balance possible differences between patients with obstetric anal sphincter injuries and those without and a stepwise univariate and multivariate logistic regression. A secondary analysis was performed to further evaluate the effect of parity, epidural anesthesia, and duration of the second stage of labor by adjusting for potential confounders. RESULTS Of 41,440 patients screened for eligibility, 22,156 met the inclusion criteria, and 15,992 were balanced after propensity score matching. Obstetric anal sphincter injuries occurred in 81 cases (0.4%), 67 (0.3%) after spontaneous delivery and 14 (0.8%) after vacuum delivery(P=.002). There was an increased odds of severe lacerations of nearly 2-fold for nulliparous women delivering by vacuum delivery (adjusted odds ratio, 2.85; 95% confidence interval, 1.19–6.81; P=.019), with a reciprocal reduction in women with spontaneous vaginal delivery (adjusted odds ratio, 0.35; 95% confidence interval, 0.15–0.84; P=.019) and at least 1 previous delivery (adjusted odds ratio, 0.51; 95% confidence interval, 0.31–0.85; P=.005). Epidural anesthesia was associated with a lower incidence of obstetric anal sphincter injuries (adjusted odds ratio, 0.54; 95% confidence interval, 0.33–0.86; P=.011). The risk of severe lacerations was independent of the duration of the second stage of labor (adjusted odds ratio, 1.00; 95% confidence interval, 0.99–1.00; P=.3), whereas the risk was reduced when mediolateral episiotomy was performed (adjusted odds ratio, 0.20; 95% confidence interval, 0.11–0.36; P<.001). Neonatal risk factors include head circumference (odds ratio, 1.50; 95% confidence interval, 1.18–1.90; P=.001) and vertex malpresentation (adjusted odds ratio, 2.71; 95% confidence interval, 1.08–6.78; P=.033). Induction of labor (adjusted odds ratio, 1.13; 95% confidence interval, 0.72–1.92; P=.6), frequent obstetrical examinations (adjusted odds ratio, 1.17; 95% confidence interval, 0.72–1.90), and women's supine position at birth (adjusted odds ratio, 1.25; 95% confidence interval, 0.61–2.55; P=.5) were further evaluated. Among severe obstetrical complications, shoulder dystocia increased the risk of obstetric anal sphincter injuries by nearly 4 times (adjusted odds ratio, 3.92; 95% confidence interval, 0.50–30.74; P=.2), whereas postpartum hemorrhage occurred 3 times more often in cases of delivery complicated by severe lacerations (adjusted odds ratio, 3.35; 95% confidence interval, 1.76–6.40; P<.001). The relationship among obstetric anal sphincter injuries, parity, and the use of epidural anesthesia was further confirmed in a secondary analysis. We found that primiparas who delivered without epidural anesthesia had the highest risk of obstetric anal sphincter injuries (adjusted odds ratio, 2.53; 95% confidence interval, 1.46–4.39; P=.001). CONCLUSION Severe perineal lacerations were found to be a rare complication of vaginal delivery. By using a robust statistical model, such as propensity score matching, we were able to investigate a broad range of antenatal and intrapartum risk factors, including use of epidural anesthesia, number of obstetrics examinations, and patient position at birth, which are usually underreported. Moreover, we found that women who delivered for the first time without epidural anesthesia had the highest risk of obstetric anal sphincter injuries.pubpu

¿Qué responden los estudiantes universitarios sobre su eficacia autorreguladora en tareas de aprendizaje?

En este trabajo analizamos las respuestas de estudiantes universitarios de Ciencias sobre sus estrategias de eficacia autorreguladora frente a los obstáculos que encuentran en el aprendizaje en tareas de lectura y de evaluaciones. El cuestionario está basado en el inventario de autoeficacia para el aprendizaje Self-Efficacy for Learning Form, SELF. Con los datos obtenidos efectuamos un análisis factorial para establecer cómo se correlacionan las variables a través del agrupamiento en factores. Los resultados de este estudio exploratorio contribuyen a conocer datos sobre la eficacia autorreguladora de los estudiantes que permitirían planificar actividades de aprendizaje autorreguladas para mejorar sus rendimientos académicos

Fetal brain hemodynamics in pregnancies at term: correlation with gestational age, birthweight and clinical outcome

Introduction: The primary aim of this study was to ascertain the strength of association between cerebral blood flow assessed in anterior (ACA), middle (MCA), and posterior (PCA) cerebral arteries and the following clinical outcomes: small for gestational age (SGA), induction of labor (IOL) for oligohydramnios and caesarean section (CS) for nonreassuring fetal status (NRFS) during labor. Material and methods: Retrospective analysis of prospectively collected data on consecutive singleton pregnancies from 40 0/7 to 41 6/7 week of gestation. UA, ACA, MCA, PCA pulsatility index (PI) were measured from 40 weeks of gestations. Furthermore, the ratios between cerebral blood flow and UA (CPR, ACA/UA and PCA/UA) were calculated and correlated with the observed outcomes. Results: Two hundred twenty-four singleton pregnancies were included in the study. Mean PI of either ACA (p = .04), MCA (p = .008), and PCA (p = .003) were lower in the SGA compared to non-SGA group; furthermore, mean PCA PI was significantly lower than MCA PI (p = .04). Furthermore, CPR (p = .016), ACA/UA (p = .02), and PCA/UA (p = .003) were significantly lower in the SGA group compared to controls. UA, ACA, MCA, and PCA PI were higher in women undergoing IOL for oligohydramnios compared to controls. Logistic regression analysis showed that CPR and PCA/UA ratio were independently associated with SGA. SGA, ACA PI, and ACA/UA were independently associated with CS for NRFS. Finally, birthweight centile, were independently associated with IOL oligohydramnios. Despite this, the predictive accuracy of Doppler in detecting any of the explored outcome was only poor to moderate. Conclusion: Redistribution of cerebral blood flow at term is significantly associated with SGA, IOL for oligohydramnios and CS for NRFS in labor. However, the predictive accuracy of Doppler at term is only poor to moderate, thus advising against its use in clinical practice as a standalone screening test for adverse perinatal outcome in pregnancies at term. Key Message Redistribution of cerebral blood flow at term is significantly associated with SGA, IOL for oligohydramnios and CS for NRFS in labor

PTH-rP and PTH-R1 Expression in Placentas from Pregnancies Complicated by Gestational Diabetes: New Insights into the Pathophysiology of Hyperglycemia in Pregnancy

Background: this study investigated the expression of parathyroid hormone-related protein (PTH-rP) and PTH/PTH-rP receptor PTH-R1 in placentas from women with gestational DM (GDM), and the relationship between PTH-R1 and PTH-rP expression and pregnancy characteristics. Methods: we prospectively enrolled 78 pregnant women with GDM, and immunochemistry for PTH-rP and PTH-R1 was performed on placentas. Patients were grouped according to the positivity of PTH-R1 or PTH-rP expression, and pregnancy characteristics were compared between the two groups. Results: PTH-rP and PTH-R1 expression were highest in the extravillous cytotrophoblast and in the decidua. In extravillous cytotrophoblast, PTH-rP expression was higher in women with abnormal at fasting glycemia compared to women with abnormal 60' or 120' glycemia (25/25, 50% vs. 6/28, 21.4%, χ2 = 6.12, p = 0.01), and PTH-R1 expression was higher in women with abnormal oral glucose tolerance test (OGTT) at fasting glycemia compared to women with abnormal 60' or 120' glycemia (37/50, 74% vs. 15/28, 53.6%, χ2 = 3.37, p = 0.06). In syncytiotrophoblast, PTH-rP-positive placentas were characterized by higher incidence of 1 min Apgar score &lt; 7 (2/9, 22.2% vs. 2/69, 2.9%, χ2 = 6.11, p = 0.01) and maternal obesity (4/9, 44.4% vs. 11/69, 16.7%, χ2 = 3.81, p = 0.05). Conclusion: placental PTH-rP and PTH-R1 expression is dependent on the type of maternal hyperglycemia, and it is associated with adverse pregnancy outcomes