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This article presents a quantitative analysis of the variables that affect the premature aging of lithiumion batteries. For this purpose, first the validation of a theoretical model developed in Matlab-Simulink is carried out by comparing the behavior of its parameters of interest with respect to a real system implemented in the laboratory. For this, parameters such as the characteristics of the cells and the environmental conditions are considered in both cases. Subsequently, once the simulation tool has been validated, load and unload cycles are performed on the model implemented in Matlab-Simulink. As part of the process, tests are carried out considering different temperatures, charge / discharge rates, and different discharge depths, with the aim of determining the impact of these parameters on the useful life of lithium-ion batteries. The final section of the document presents the results of the experiment where, among other aspects, the influence of ambient temperature on the deterioration of lithium-ion batteries, as well as the impact of a charge / discharge process of cells studied with high levels of electrical current. [ABSTRACT FROM AUTHOR]

In France, the current recommendation is to perform a routine abdominopelvic ultrasound in any child under 2 years of age who is suspected to have been abused. We retrospectively studied the relevance of this practice in our center over the past fifteen years. This was a descriptive, retrospective study of all children under 2 years of age who had been subject to suspected abuse. Abdominal images and reports were reviewed and cross-referenced with possible clinical and biological signs. Four hundred and five children were included between 2006 and 2020, of whom 296 underwent abdominal imaging (2 initial abdominopelvic CT scans, 4 ultrasounds followed by CT scans, and 290 ultrasounds alone). Four examinations revealed traumatic abnormalities related to abuse. These four children all had clinical or biological anomalies. In the absence of clinical or biological signs, no imagery showed any abnormality related to abuse.

Background: Diffusion-weighted imaging (DWI) has been described to correlate with tumoural necrosis in response to preoperative chemotherapy for osteosarcoma., Objective: To assess the accuracy of DWI in evaluating the response to neoadjuvant chemotherapy at the mid-course treatment of long-bone osteosarcoma and in predicting survival., Materials and Methods: We conducted a prospective single-centre study over a continuous period of 11 years. Consecutive patients younger than 20 years treated with a neoadjuvant regimen for peripheral conventional osteosarcoma were eligible for inclusion. Magnetic resonance imaging (MRI) with DWI was performed at diagnosis, and mid- and end-course chemotherapy with mean apparent diffusion coefficients (ADC) calculated at each time point. A percentage less than or equal to 10% of the viable residual tissue at the histological analysis of the surgical specimen was defined as a good responder to chemotherapy. Survival comparisons were calculated using the Kaplan-Meier method. Uni- and multivariate analyses with ADC change were performed by Cox modelling. This is an expansion and update of our previous work., Results: Twenty-six patients between the ages of 4.8 and 19.6 years were included, of whom 14 were good responders. At mid-course chemotherapy, good responders had significantly higher mean ADC values (P=0.046) and a higher increase in ADC (P=0.015) than poor responders. The ADC change from diagnosis to mid-course MRI did not appear to be a prognosticator of survival and did not impact survival rates of both groups., Conclusion: DWI at mid-course preoperative chemotherapy for osteosarcoma should be considered to evaluate the degree of histological necrosis and to predict survival. The anticipation of a response to neoadjuvant treatment by DWI may have potential implications on preoperative management., (© 2021. The Author(s).)

Background: Contrast-enhanced MRI is often used for diagnosis and follow-up of children with inflammatory bowel disease., Objective: To compare the accuracy of diffusion-weighted MRI (DWI) to contrast-enhanced MRI in children with known or suspected inflammatory bowel disease., Materials and Methods: This retrospective, consecutive study included 55 children. We used ileo-colonoscopy and histology as the reference standard from the terminal ileum to the rectum, and contrast-enhanced MRI as the reference standard proximal to the terminal ileum. DWI and contrast-enhanced MRI sequences were independently reviewed and compared per patient and per segment to these reference standards and to the follow-up for each child., Results: We obtained endoscopic data for 340/385 colonic and ileal segments (88%). The rate of agreement per segment between DWI and endoscopy was 64%, and the rate of agreement between contrast-enhanced MRI and endoscopy was 59%. Per patient, sensitivity and specificity of bowel wall abnormalities as compared to the endoscopy were 87% and 100% for DWI, and 70% and 100% for contrast-enhanced MRI, respectively. Positive and negative predictive values were, respectively, 100% and 57% for DWI, and 96% and 41% for contrast-enhanced MRI. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of DWI compare to contrast-enhanced MRI in the segments proximal to the terminal ileum were 90%, 98%, 90%, 98% and 96%, respectively., Conclusion: The diagnostic performance of DWI is competitive to that of contrast-enhanced MRI in children with known or suspected inflammatory bowel disease.

This pictorial essay will initially present the origin, definitions, objectives and main principles of the segmental approach to congenital heart diseases. Then, through ultrasound scans iconography we will consider its practical applications to prenatal screening. Eventually, through both ultrasound and MRI cases, we will discuss its potential use in fetal diagnostic evaluation., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Objective: The objective of this study was to determine the frequency and the nature of associated anomalies, especially malformations and chromosome abnormalities, in a population of fetuses with an aberrant right subclavian artery (ARSA)., Materials and Methods: This is a 7-year descriptive study. All patients whose fetus had an ARSA diagnosed by ultrasound performed during the 1st, 2nd, or 3rd trimester of pregnancy were included, regardless of their risk of chromosomal abnormalities., Results: Between May 2007 and April 2014, an ARSA was diagnosed in 120 fetuses. The outcome was found in 108 cases (90%). ARSA was an isolated finding in 54/108 cases (50%). In 20% (22/108) of the fetuses, chromosomal abnormalities were detected. No chromosomal abnormalities were found in fetuses with an isolated ARSA. 82% (18/22) of chromosomal abnormalities were usual, such as trisomies 21 and 18, monosomy X, and 22q11.2 deletion. 21% (23/108) of the fetuses presenting an ARSA were associated with having a congenital heart disease., Conclusion: The presence of an isolated ARSA is a condition rarely associated with a chromosomal abnormality. The decision to perform an invasive karyotyping procedure under such circumstances or not may be made according to the principle of parental autonomy after extensive counselling and mostly a thorough assessment of the fetus., (© 2016 S. Karger AG, Basel.)