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Measurement of the plasma generated diamagnetic flux on tokamak à configuration variable (TCV) is used to derive the plasma pressure, as on other magnetic confinement experiments. However, specificities of the device make the measurement more difficult: for passive stabilization of the vertical position of highly elongated plasmas, the vessel has a low electrical resistivity, leading to large image currents in the vessel. For the same reason the plasma must also be kept close to the conducting wall, so that the in-vessel double loop method usually used to compensate for these currents cannot be applied. In order to achieve proper compensation, the diamagnetic measurement diagnostic on TCV uses the signal from a single loop wound outside the vessel in combination with appropriate signal processing that accurately matches the fast component of the induced vessel current. This allows extraction of the plasma diamagnetic flux with a remarkable bandwidth, of ∼10 kHz, and with the required accurate compensation of 0.05 mWb out of 2 Wb. As a result, rapid changes in plasma pressure can be studied, for example during additional heating power modulation or fast plasma instabilities. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the design of tokamak configuration variable to create plasma shapes. Requirement of plasma flexibility; Description of the magnetic sensor geometry, fabrication, calibration, associated electronics and diagnostic operation in sensor position and monitoring; Method for deriving corrections in sensor position and calibration.

An accurate and reliable measurement of poloidal β is essential to assess the performances of Joint European Torus (JET). The diamagnetic loop can measure β values as low as 0.1 in JET discharges with a plasma current larger than 2 × 10[sup 6] A. The instrumentation used includes a flux loop rigidly fitted on a toroidal field (TF) coil, a large Rogowski coil measuring the TF busbar current, and a displacement gauge measuring the TF coil expansion. The fluxes to be compensated originate, in order of importance, from the TF current, the eddy current in the vessel, the TF coil expansion, and the stray coupling with the poloidal fields. The TF and eddy currents must be particularly well compensated on JET since the plasma current starts before the toroidal field has reached its plateau value. Comparison between the diamagnetic and other evaluations of β shows a good agreement. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to determine a combination of third-trimester echocardiographic parameters for improving the prenatal prediction of coarctation of the aorta (CoA) after birth., Methods: We included all cases of suspected CoA during fetal echocardiography performed in the second and/or third trimester of pregnancy at Gaslini Children's Hospital between January 2010 and December 2020. The last prenatal ultrasound evaluation was reviewed considering most of the echocardiographic criteria were already published for prenatal CoA diagnosis. Associated minor cardiac anomalies, such as a ventricular septal defect, persistent left superior vena cava (PLSCV), and redundant foramen ovale (FO) membrane, as well as postnatal outcomes, were reported. Initial perinatal management was defined based on the risk stratification of CoA during prenatal echocardiography. Neonates were divided into two groups depending on the presence or absence of CoA after birth., Results: A total of 91 fetuses with CoA suspicion were selected, of which 27 (30%) were confirmed with CoA after birth and underwent surgical repair. All cardiac parameters except redundant FO membrane and PLSCV showed a significant correlation with CoA. Statistical analysis confirmed that cardiovascular disproportion with right predominance carries an increased risk for occurrence of CoA, especially if already evident during the ultrasound evaluation in the second trimester. Aortic valve (AV) z-score and distal transverse aortic arch (TAA) z-score resulted as the best predictors of CoA after birth. The best cutoff point for CoA discrimination with ROC analysis was an AV z-score of -1.25 and a distal TAA z-score of -0.37. A total of 46% of those without CoA were diagnosed with a cardiac defect, which was not diagnosed in utero, pulmonary hypertension, or a genetic syndrome., Conclusion: The current criteria for diagnosing CoA in utero allow accurate diagnosis of most severe cases but the rate of false positives remains relatively high for milder cases. A combination of anatomic and functional echocardiographic parameters might be used in stratifying the risk of CoA. We proposed the AV and the TAA diameter z-scores as the best predictors of CoA after birth. In addition, neonates without CoA deserve proper monitoring at birth because prenatal evidence of a significant cardiovascular discrepancy between the right and left cardiac structures has an inherent risk for additional morbidity postnatally., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tuo, Paladini, Marasini, Buratti, De Tonetti, Calevo and Marasini.)

Objective: The aim of the study is to describe a delivery room intensive care unit (DRICU) model and evaluate its effectiveness in preventing morbidity and mortality in high-risk newborns. Design: This retrospective case series includes all DRICU procedures performed from 2016 to 2020. Setting: Gaslini Children's Hospital is a major pediatric tertiary care center where high-risk pregnancies are centralized. The Neonatal and Pediatric Intensive Care Unit admits every year about 100 high-risk newborns. Patients: The selected patients are newborns at risk of critical conditions immediately after birth for respiratory or cardiovascular congenital disorders. Interventions: The perinatal plan is defined by the multidisciplinary team of Fetal and Perinatal Medicine. The DRICU procedure provides highly specialized care through a protocol that includes logistics, personnel, equipment, and clinical pathways. Main Outcome Measures: The primary outcome is the prevention of acute complications and mortality in the delivery room and early neonatal period. Results: From 2016 to 2020, 40 DRICU procedures were performed. The main prenatal diagnoses included congenital heart disease with a high risk of life-threatening events immediately after birth (38%), congenital diaphragmatic hernia (35%), and fetal hydrops/hydrothorax (23%). Mean gestational age was 35.9 weeks (range: 31-39), and mean birth weight was 2,740 grams (range: 1,480-3,920). DRICU assistance completed in all patients by neonatal intensivists included tracheal intubation and arterial and central venous cannulation; complex procedures such as ex-utero intrapartum technique and extracorporeal membrane oxygenation cannulation are described. No deaths nor severe acute complications occurred in the delivery room or in the immediate postnatal period. Conclusions: The outcome in critical newborns is potentially affected by planned assistance strategies and specialized competencies through the implementation of a DRICU protocol., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Buratti, Lampugnani, Faggiolo, Buffoni, Paladini, De Tonetti, Tuo, Marasini, Mattioli and Moscatelli.)

Human factors are the most relevant issues contributing to adverse events in obstetrics. Specific training of Crisis Resource Management (CRM) skills (i.e., problem solving and team management, resource allocation, awareness of environment, and dynamic decision-making) is now widespread and is often based on High Fidelity Simulation. In order to be used as a guideline in simulated scenarios, CRM skills need to be mapped to specific and observable behavioral markers. For this purpose, we developed a set of observable behaviors related to the main elements of CRM in the delivery room. The observational tool was then adopted in a two-days seminar on obstetric hemorrhage where teams working in obstetric wards of six Italian hospitals took part in simulations. The tool was used as a guide for the debriefing and as a peer-to-peer feedback. It was then rated for its usefulness in facilitating the reflection upon one's own behavior, its ease of use, and its usefulness for the peer-to-peer feedback. The ratings were positive, with a median of 4 on a 5-point scale. The CRM observational tool has therefore been well-received and presents a promising level of inter-rater agreement. We believe the tool could have value in facilitating debriefing and in the peer-to-peer feedback., Competing Interests: The authors declare no conflict of interest.

Background: Simulation in healthcare has proved to be a useful method in improving skills and increasing the safety of clinical operations. The debriefing session, after the simulated scenario, is the core of the simulation, since it allows participants to integrate the experience with the theoretical frameworks and the procedural guidelines. There is consistent evidence for the relevance of non-technical skills (NTS) for the safe and efficient accomplishment of operations. However, the observation, assessment and feedback on these skills is particularly complex, because the process needs expert observers and the feedback is often provided in judgmental and ineffective ways. The aim of this study was therefore to develop and test a set of observation and rating forms for the NTS behavioural markers of multi-professional teams involved in delivery room emergency simulations (MINTS-DR, Multi-professional Inventory for Non-Technical Skills in the Delivery Room)., Methods: The MINTS-DR was developed by adapting the existing tools and, when needed, by designing new tools according to the literature. We followed a bottom-up process accompanied by interviews and co-design between practitioners and psychology experts. The forms were specific for anaesthetists, gynaecologists, nurses/midwives, assistants, plus a global team assessment tool. We administered the tools in five editions of a simulation training course that involved 48 practitioners. Ratings on usability and usefulness were collected., Results: The mean ratings of the usability and usefulness of the tools were not statistically different to or higher than 4 on a 5-point rating scale. In either case no significant differences were found across professional categories., Conclusion: The MINTS-DR is quick and easy to administer. It is judged to be a useful asset in maximising the learning experience that is provided by the simulation.

A rapid method for screening potential dye ligands for use in affinity chromatography is described. Textile dyes were non-covalently coupled to a cross-linked polysaccharide Sepharose(R) matrix. Yeast alcohol dehydrogenase (ADH) was used as the model protein for evaluating the screening system. A homogenate from baker's yeast was used as the crude source of enzyme. Batchwise adsorption and elution were used to evaluate the individual dyes. The influence of pH and ionic strength in the binding and elution steps was evaluated. Batch isotherms were used to evaluate parameter characteristics. Experimental data obtained were fitted to Langmuir isotherms to determine the maximum binding capacity and the dissociation constant for each dye evaluated in this study. A dynamic binding capacity of 107.6 units of ADH/g of resin was determined for Procion Turquoise MXG dye by frontal analysis. Specific elution with NAD+ and non-specific elution with 50 mM Tris/HCl buffer, pH 8.5, were tested when Procion Turquoise MXG was used, giving purification factors of 53.5 and 4.4 respectively. This screening technique is inexpensive and can be performed in a few hours. It was possible to predict the performance of different reactive dyes in this way, and the influence of pH and salt on the binding behaviour was demonstrated.