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Rare Earth Elements (REE) and several trace elements abundances in mussel's shells collected along the St. Lawrence River, the Estuary, and the Gulf of St. Lawrence (EGSL) reveal coherent chemical variations, with a sharp contrast between freshwater and seawater bivalves. In freshwater mussel's shells, Rare Earth Elements and Y (REY) patterns are rather flat. Their Mn and Ba concentrations are higher than those of EGSL mussel shells, which are much richer in Sr. Shale-normalized REY abundances in mussel's shells from the EGSL show positive anomalies in La and Y and well-marked negative anomalies in Ce, reflecting those of seawater. Prince Edward Island shells show light REE depletion relative to PAAS, positive La and Y anomalies, and negative Ce anomalies. Our data confirm the lack of detectable Gd pollution in the St. Lawrence River and in the EGSL, as well as Pb pollution at the mouth of the Saguenay Fjord and near Rimouski., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Over the last decade, convolutional neural networks have emerged and advanced the state-of-the-art in various image analysis and computer vision applications. The performance of 2D image classification networks is constantly improving and being trained on databases made of millions of natural images. Conversely, in the field of medical image analysis, the progress is also remarkable but has mainly slowed down due to the relative lack of annotated data and besides, the inherent constraints related to the acquisition process. These limitations are even more pronounced given the volumetry of medical imaging data. In this paper, we introduce an efficient way to transfer the efficiency of a 2D classification network trained on natural images to 2D, 3D uni- and multi-modal medical image segmentation applications. In this direction, we designed novel architectures based on two key principles: weight transfer by embedding a 2D pre-trained encoder into a higher dimensional U-Net, and dimensional transfer by expanding a 2D segmentation network into a higher dimension one. The proposed networks were tested on benchmarks comprising different modalities: MR, CT, and ultrasound images. Our 2D network ranked first on the CAMUS challenge dedicated to echo-cardiographic data segmentation and surpassed the state-of-the-art. Regarding 2D/3D MR and CT abdominal images from the CHAOS challenge, our approach largely outperformed the other 2D-based methods described in the challenge paper on Dice, RAVD, ASSD, and MSSD scores and ranked third on the online evaluation platform. Our 3D network applied to the BraTS 2022 competition also achieved promising results, reaching an average Dice score of 91.69% (91.22%) for the whole tumor, 83.23% (84.77%) for the tumor core and 81.75% (83.88%) for enhanced tumor using the approach based on weight (dimensional) transfer. Experimental and qualitative results illustrate the effectiveness of our methods for multi-dimensional medical image segmentation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A simple ICP-MS procedure for the determination of trace element concentrations in GBCAs is described here. Abundances of most of the REEs, Y, Ba and Pb concentrations were determined. We confirm that GBCAs contain traces of non-Gd REEs, Y, Ba and Pb. REE patterns of the five GBCAs actually administered in France have been obtained. They display specific shapes that make it possible to identify the different Gd oxides oxides used by pharmaceutical laboratories to produce them. Our method enables us to quickly evaluate the quantities of impurities in these products and, if necessary, to follow the evolution of their quality in the future. The presence of small but not negligible quantities of Y and REEs other than Gd cannot be ignored in these products, and their behaviour in the human body must be considered. The concentrations measured for Pb and Ba, on the other hand, are much lower and do not pose any particular problems., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The determination of rare earth elements (REEs) and Y in carbonates can be complicated by low REE abundances and the presence of significant amounts of Ba resulting in problematic interferences when analysed by ICP-MS. We describe here a novel ion-exchange method using the DGA resin (TODGA), combined with addition of a Tm spike, which allows the separation of the REEs+Y as a whole prior to analysis using an Element XR ICP-MS. This method was validated with results obtained on three different reference carbonate materials (CAL-S, JLs-1 and BEAN, an in-house standard), yielding reproducibility levels better than 3% (RSD) in most cases. This new separation scheme is particularly well suited for carbonate samples having very low REE contents, but could be equally applied to various rock types and organic-rich sample matrices whenever quantitative Ba removal is required., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objectives: The aim of this work was to study physiological aortic arch three-dimensional displacement using non-rigid registration methods and magnetic resonance imaging (MRI)., Materials and Methods: Ten healthy volunteers underwent thoracic MRI. Prospective cardiac gating was performed with a 3D turbo field echo sequence to obtain end-systolic and end-diastolic MR images. The rigid and elastic behavior between these two cardiac phases was detected and compared using either an affine or an elastic registration method. To assess reproducibility, a second MRI acquisition was performed 14 days later., Results: Affine registration between the end-systolic and end-diastolic MR images showed significant global translations of the aortic arch and the supra-aortic vessels in the x, y, and z directions (2.02 ± 1.6, -0.71 ± 1.1, and -1.21 ± 1.4 mm, respectively). Corresponding elastic registration indicated significant local displacement with a vector magnitude of 5.1 ± 0.89 mm for the brachiocephalic artery (BCA), of 4.26 ± 0.83 mm for the left common carotid artery (LCCA), and of 4.8 ± 0.86 mm for the left subclavian artery (LSCA). There was a difference in displacement between the supra-aortic trunks of the order of 2 mm. Vector displacement was not statistically different between the repeated acquisitions., Conclusions: The present results showed important deformations in the ostia of supra-aortic vessels during the cardiac cycle. It seems that aortic arch motions should be taken into account when designing and manufacturing fenestrated endografts. The elastic registration method provides more precise results, but is more complex and time-consuming than other methods., (Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: A colloid cyst is a rare benign tumor. If indicated, surgical treatment can be realized using a microsurgical technique or an endoscopic technique. We report an uncommon complication of a third ventricle colloid cyst endoscopic removal., Case Description: The cyst was incidentally discovered on computed tomography scan workup for mild head trauma in a 20-year-old male. Minor headache and minor memory loss were noted on clinical examination. Magnetic resonance imaging workup revealed obstructive hydrocephaly of the lateral ventricles associated with left uncal herniation. Surgery was uneventful. However, left oculomotor palsy was noted postoperatively. Workup revealed oculomotor nerve injury and isolated left mammillary body ischemia, secondary to worsened uncal herniation. This worsening might be caused by acute left ventricle hydrocephaly ascribed to interventricular foramen obstruction during cyst removal., Conclusion: Therefore, in similar presentation, realizing septum fenestration before cyst removal should relieve the pressure in the lateral ventricles thus decreasing the risk of herniation., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Ischemia of the areas supplied by the anterior cerebral artery is relatively uncommon. In addition, combined hemiballismus and masturbation have rarely been reported in patients with cerebrovascular disease. We describe herein a 62-year-old right-handed man simultaneously exhibiting right side hemiballismus and involuntary masturbation with the left hand after bilateral infarction of the anterior cerebral artery territory. Right side hemiballismus was related to the disruption of afferent fibers from the left frontal lobe to the left subthalamic nucleus. Involuntary masturbation using the left hand was exclusively linked to a callosal type of alien hand syndrome secondary to infarction of the right side of the anterior corpus callosum. After 2 weeks, these abnormal behaviours were completely extinguished. This report stresses the wide diversity of clinical manifestations observed after infarction of the anterior cerebral artery territory.

Background and Purpose: Proton spectroscopy and quantitative diffusion-weighted imaging (DWI) were used to investigate the pertinence of N-acetyl aspartate (NAA) as a reliable marker of neuronal density in human stroke., Methods: The time courses of tissue water apparent diffusion coefficient (ADC(w)) and metabolite T2 were investigated on a plane corresponding to the largest area of cerebral infarction, within and outside the site of infarction in 71 patients with a large cortical middle cerebral artery territory infarction., Results: Significant reductions are seen in NAA T2 deep within the infarction during the period comprised between 5 and 20 days postinfarction; the relaxation times appearing to normalise several months after stroke. After an acute reduction in ADC(w), the pseudonormalisation of ADC(w) occurs at 8-12 days after the ischaemic insult. The minimum in N-acetyl aspartate T2 relaxation times and the pseudonormalisation of ADC(w) appear to coincide., Conclusions: The data suggest that modifications in the behaviour of the observed proton metabolites occur during the period when the vasogenic oedema is formed and cell membrane integrity is lost. For this reason, NAA may not be a reliable marker of neuronal density during this period.

Many of the previous studies of vascular dementia using proton magnetic resonance (MR) spectroscopy had been carried out on white matter. However, no proton spectroscopic data of the subcortical gray matter are available in such disease. We report two cases suffering from vascular dementia, with an unilateral N-acetylaspartate (NAA) decrease on subcortical gray matter. This significant reduction in NAA ratios was associated with an increase of choline on the ipsilateral centrum semiovale. We discuss the pathophysiology of these cases.