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In automotive industry, the FE fatigue analysis of mechanical structures made of steel thin walled parts and seam welded assemblies uses a dedicated technique based on shell element modelling for components and on 1D rigid elements for welds. This method has been validated with several intensive fatigue test campaigns using gas metal arc welded samples with different assemblies, for both bending and torsional loads. The fatigue results are relative to crack initiation at the weld toe with bending normal stress or with longitudinal shear stress for several load ratios. The purpose of the current work is the transposition of the initial method to another FE welded model. In a recent IIW guideline for the assessment of weld root fatigue, a shell element weld model has been proposed for seam weld fatigue assessment in case of weld root crack initiation. The idea is to analyse the possible extension of this FEA weld element model for weld toe fatigue analysis and several comparisons of stress results are detailed and discussed. Different fatigue criteria are used to verify the correlation with the fatigue test results. First, the approach is based on maximum shear stress, then structural stress is calculated and results are compared to IIW S/N curves.

The prevailing electrode fabrication method for lithium-ion battery electrodes includes calendering at high pressures to densify the electrode and promote adhesion to the metal current collector. However, this process increases the tortuosity of the pore network in the primary transport direction and imposes severe tradeoffs between electrode thickness and rate capability. With the aim of understanding the impact of pore tortuosity on electrode kinetics, and enabling cell designs with thicker electrodes and improved cost and energy density, we use here freeze-casting, a shaping technique able to produce low-tortuosity structures using ice crystals as a pore-forming agent, to fabricate LiNi0.8Co0.15Al0.05O2 (NCA) cathodes with controlled, aligned porosity. Electrode tortuosity is characterized using two complementary methods, X-ray tomography combined with thermal diffusion simulations, and electrochemical transport measurements. The results allow comparison across a wide range of microstructures, and highlight the large impact of a relatively small numerical change in tortuosity on electrode kinetics. Under galvanostatic discharge, optimized microstructures show a three- to fourfold increase in area-specific capacity compared to typical Li-ion composite electrodes. Hybrid pulse power characterization (HPPC) demonstrates improved power capability, while dynamic stress tests (DST) shows that an area-specific area capacity corresponding to 91% of the NCA galvanostatic C/10 capacity could be reached.

Industrial structures undergo complex loading often unsuitable for the design and validation phases of their development. Engineers seek simplified signals to replace them, yet equivalent in terms of fatigue. A general framework for the construction of fatigue equivalent loads is presented, intended to take into account some uncertainty on the structure to which it will apply. The guiding idea is to describe this uncertainty thanks to parameters of a model of the structure, and then to assure the equivalence of damage or failure behavior over the whole range of expected parameters. The approach is applied in the case of structures undergoing multiple inputs of concentrated force.

Relations between existing spot-weld finite element models and the mechanical behaviour of spot-weld are investigated for fatigue design application. Specifically, the different zones that constitute the numerical model are interrogated with respect to physical observation. In order to identify the Mechanical Influence Area of the Spot-Weld here designated as “MIASW” we propose a methodology to determine numerically its size. Hence, we develop a finite element coupon representing a spot-weld under a basis of four unit load cases. The coupon provides mechanical quantities of interest that allows us to characterize the spot-weld response that shell element are unable to represent. This response is crucial to be captured for further fatigue analysis.

Background: Chemotherapy using carboplatin and etoposide (CE) is frequently pragmatically proposed to treat metastatic prostate cancer (mPC), both primary small-cell neuroendocrine (PSC-NE) carcinoma and adenocarcinoma with or without neuroendocrine (NE) marker elevation. However, the real benefit of CE is poorly reported in the recent therapeutic context., Methods: We retrospectively analyzed the efficacy and tolerance of CE chemotherapy in these three different groups of mPC patients. Efficacy endpoints included radiological response, progression-free survival (PFS), and overall survival (OS), as well as PSA response and PFS2/PFS1 ratio in patients with adenocarcinoma., Results: Sixty-nine patients were included in this single-center study ( N = 18 with PSC-NE carcinoma and 51 with adenocarcinoma with ( N = 18) or without ( N = 33) NE marker elevation). Patients with adenocarcinoma were highly pretreated with next-generation hormonal agents (NHAs) and taxanes. In patients with adenocarcinoma, a PSA response ≥50% was observed in six patients (15.8%), four of whom had NE marker elevation. The radiological response was higher in PSC-NE and tended to be higher in adenocarcinoma when NE marker elevation was present. Comparing patients with adenocarcinoma with vs. without NE marker elevation, the median PFS was 3.7 and 2.1 months and the median OS was 7.7 and 4.7 months, respectively. Overall, 62.3% of patients experienced grade 3-4 adverse events (mainly hematological), and three treatment-related deaths were recorded., Conclusion: Reports of the clinical results of CE suggest that we should not mix PSC-NE and castration-resistant adenocarcinoma of the prostate. In patients with heavily pretreated adenocarcinoma, the benefit/risk ratio of CE chemotherapy seems unfavorable due to poor response and high toxicity.

Background and Purpose: The main purpose of this retrospective study was to evaluate inter-software variability in patients affected of a high-grade glioma for the post-processing of dynamic susceptibility contrast (DSC 1 ) perfusion imaging in MRI. 2 MATERIALS AND METHODS: The included patients were either anaplastic astrocytoma (WHO 3 grade III) or glioblastoma (WHO grade IV) located in the cerebral parenchyma. The postprocessing of 54 MRI-DSC imaging from 46 patients using both Intellispace.. (Philips) and Olea.. (Olea Medical) software was performed. The hemodynamic parameter studied was the normalised relative cerebral blood volume corrected for the T1 leakage effect (nrCBVc 4 ). The inter-operator variabilities were also evaluated., Results: Regarding inter-software reproducibility, Cohen...s Kappa from therapeutic follow-up obtained were 0.61, close to the recommended limit (0.60). Subgroups were created to complete the analysis and to evaluate the partial volume effect. Even if necrosis or vascular structures from regions of interest (ROI 5 ) were avoided, results did not improve. ROI of a minimum area of 250...mm 2 yielded a Cohen...s Kappa of 0.65. The inter-operator reproducibility on Intellispace and Olea were 0.90 and 0.73 respectively, which is satisfactory., Conclusion: The reproducibility between Intellispace and Olea was below recommended threshold in a clinical context. This discrepancy can be explained by the partial volume effect and the models used. ROI with an area of at least 250...mm 2 improves this reproducibility and becomes acceptable., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Introduction: Synthetic magnetic resonance imaging (SyMRI) is a novel quantitative and qualitative technique that permits the reconstruction of multiple image contrasts and quantitative maps from a single scan, thereby providing quantitative information and reducing scan times. The purpose of this study is to characterize intracranial meningiomas using SyMRI., Methods: The study included 35 patients with meningiomas (6 males, 29 females; mean age 61 ± 17 years; range 21-90 years). Using 3T MR scanners, SyMRI was performed in addition to conventional FSET2, FLAIR, DWI, T1, and T1 with gadolinium. SyMRI software was used to generate T1, T2, and PD quantitative maps. Osirix MD was used to measure quantitative values of T1, T2, and PD using a ROI., Results: We analyzed 42 meningiomas, 8 of which were associated with edema, and 5 contained calcifications. Mean relaxivity values of meningiomas on synthetic T1, T2, and PD maps at 3T MRI were 1382.6 ± 391.7 ms, 95.6 ± 36.5 ms, and 89.1 ± 9.7 pu, respectively. Signal intensities in terms of T1, T2, and PD did not differ significantly between meningiomas with and without edema (p = .994, p = .356, and p = .221, respectively), nor between meningiomas containing and not containing calcifications (p = .840, p = .710, and p = .455, respectively). Values of T1 and T2 measured in meningiomas and the normal-appearing white matter approximated reference values found in the literature with other quantitative methods., Conclusion: The presented method offers a novel approach to characterize meningiomas through their relaxation parameters measured with a SyMRI sequence., (© 2022 The Authors. Brain and Behavior published by Wiley Periodicals LLC.)

Anatomical studies on the radial side of the scaphoid mention inter-ligamentous connections, but without detailed description of their relations to one another. The purpose of this study was to provide an anatomical and radiological description of the ligamentous structure on the radial side of the scaphoid. High-field 3-Tesla 3D MRI scans of 7 cadaveric formaldehyde-fixed wrists were performed to assess the presence and location of each ligament. Dissection was performed in 10 wrists under microscopy on the radial side to assess the dimensions, anatomical variations and angles between ligaments in various wrist positions during in intracarpal pronation/supination, flexion/extension and ulnar/radial deviation. This study confirmed that the same ligament configuration was found on MRI and on dissection. The scaphotrapezial ligament, dorsal intercarpal ligament and radial collateral ligament fibers merge along the dorsal ridge of the scaphoid. The fibers of the radial collateral and radioscaphocapitate ligaments could be distinguished in only 4/10 specimens. Wrist position changes from intracarpal pronation to supination produced major changes in angle between the scaphotrapezial and dorsal intercarpal ligaments, while other position changes affected this angle only slightly. 3D MRI sequences allow these structures to be systematically analyzed in case of scapholunate instability. Further studies should be conducted to assess the biomechanical properties of these ligaments and the clinical consequences of isolated injury in this region., (Copyright © 2022 SFCM. Published by Elsevier Masson SAS. All rights reserved.)

Background and Purpose: Controversy exists as to whether ADC histograms are capable to distinguish human papillomavirus-positive (HPV+) from human papillomavirus-negative (HPV-) oropharyngeal squamous cell carcinoma. We investigated how the choice of b-values influences the capability of ADC histograms to distinguish between the two tumor types., Materials and Methods: Thirty-four consecutive patients with histologically proved primary oropharyngeal squamous cell carcinoma (11 HPV+ and 23 HPV-) underwent 3T MR imaging with a single-shot EPI DWI sequence with 6 b-values (0, 50, 100, 500, 750, 1000 s/mm 2 ). Monoexponentially calculated perfusion-sensitive (including b =0 s/mm 2 ) and perfusion-insensitive/true diffusion ADC maps (with b ≥ 100 s/mm 2 as the lowest b-value) were generated using Matlab. The choice of b-values included 2 b-values (ADC b0-1000 , ADC b100-1000 , ADC b500-1000 , ADC b750-1000 ) and 3-6 b-values (ADC b0-750-1000 , ADC b0-500-750-1000 , ADC b0-50-100-1000 , ADC b0-50-100-750-1000 , ADC b0-50-100-500-750-1000 ). Readers blinded to the HPV- status contoured all tumors. ROIs were then copied onto ADC maps, and their histograms were compared., Results: ADC histogram metrics in HPV+ and HPV- oropharyngeal squamous cell carcinoma changed significantly depending on the b-values. The mean ADC was lower, and skewness was higher in HPV+ than in HPV- oropharyngeal squamous cell carcinoma only for ADC b0-1000, ADC b0-750-1000 , and ADC b0-500-750-1000 ( P < .05), allowing distinction between the 2 tumor types. Kurtosis was significantly higher in HPV+ versus HPV- oropharyngeal squamous cell carcinoma for all b-value combinations except 2 perfusion-insensitive maps (ADC b500-1000 and ADC b750-1000 ). Among all b-value combinations, kurtosis on ADC b0-1000 had the highest diagnostic performance to distinguish HPV+ from HPV- oropharyngeal squamous cell carcinoma (area under the curve = 0.893; sensitivity = 100%, specificity = 82.6%). Acquiring multiple b-values for ADC calculation did not improve the distinction between HPV+ and HPV- oropharyngeal squamous cell carcinoma., Conclusions: The choice of b-values significantly affects ADC histogram metrics in oropharyngeal squamous cell carcinoma. Distinguishing HPV+ from HPV- oropharyngeal squamous cell carcinoma is best possible on the ADC b0-1000 map., (© 2022 by American Journal of Neuroradiology.)

Background: Global health systems are shifting toward value-based health care to improve patient outcomes in the face of rising health care costs. The challenge is to identify standardized outcome measurements that allow optimal quality-of-care monitoring and comparison to optimize medical practices and patient pathways. A common outcomes definition is required, including medical results (Clinical Reported Outcomes Measurements [CROMs]) and quality-of-life components that matter most to patients (Patient-Reported Outcomes Measurements [PROMs]), which are particularly important for severe pathologies with short life expectancy such as pancreatic cancer. This study aimed to create standardized metrics that could be used for outcomes analysis of pancreatic cancer care., Methods: A multidisciplinary working group (WG) was assembled. A systematic review was performed to collect the most used outcomes in clinical studies of pancreatic cancers. The study reviewed 570 studies published in the last 10 years. From these studies, 3370 outcomes, including CROMs, and PROMs, were listed and prioritized. The WG reached a consensus on key outcomes, proposed groupings for CROMs and PROMs, identified existing questionnaires that could be used for PROMs collection, and set the timeline for data collection. To refine and validate the final outcomes set, an international external committee completed a Delphi process (two rounds for both CROMS and PROMs)., Results: After the systematic literature review, the WG selected 102 outcomes (92 CROMs and 10 PROMs) for submission to the international Delphi vote committee. The committee retrained 89 outcomes (78 CROMs and 11 PROMs). For the PROMs, the WG and the international external committee chose a validated questionnaire, the Functional Assessment of Cancer Therapy-Hepatobiliary, which covers all of the 11 selected PROMs., Conclusions: A standardized set of outcome measures that need to be validated through international health outcome comparisons and quality-of-care assessments was built. Pilot projects are underway to test and optimize the approach in real-life conditions.