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Presents a novel technique for simulations of viscoelastic flows derived from the Brownian configuration field method. Comparison with traditional methods; Sample application to the benchmark problem.

Background: To contain and curb the spread of COVID-19, the governments of countries around the world have used different strategies (lockdown, mandatory vaccination, immunity passports, voluntary social distancing, etc)., Objective: This study aims to examine the reactions produced by the public announcement of a binding political decision presented by the president of the French Republic, Emmanuel Macron, on July 12, 2021, which imposed vaccination on caregivers and an immunity passport on all French people to access restaurants, cinemas, bars, and so forth., Methods: To measure these announcement reactions, 901,908 unique tweets posted on Twitter (Twitter Inc) between July 12 and August 11, 2021, were extracted. A neural network was constructed to examine the arguments of the tweets and to identify the types of arguments used by Twitter users., Results: This study shows that in the debate about mandatory vaccination and immunity passports, mostly "con" arguments (399,803/847,725, 47%; χ 2 6 =952.8; P<.001) and "scientific" arguments (317,156/803,583, 39%; χ 2 6 =5006.8; P<.001) were used., Conclusions: This study shows that during July and August 2021, social events permeating the public sphere and discussions about mandatory vaccination and immunity passports collided on Twitter. Moreover, a political decision based on scientific arguments led citizens to challenge it using pseudoscientific arguments contesting the effectiveness of vaccination and the validity of these political decisions., (©Jessica S M Gable, Romy Sauvayre, Cédric Chauvière. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 23.11.2023.)

Positron emission tomography (PET) imaging of the myelin sheath is a powerful tool to investigate multiple sclerosis, monitor its evolution, and support drug development. Radiotracers based on N,N -dimethylaminostilbene (MeDAS) fluorinated analogs have been designed for myelin PET imaging but were never translated to humans. We have synthesized three original fluorinated analogs of MeDAS with low metabolic rates for which binding to myelin in a healthy rat brain was demonstrated by fluorescence microscopy. A tosyl precursor was synthesized for the lead compound PEGMeDAS and automated fluorine-18 radiolabeling afforded [ 18 F]PEGMeDAS in 25 ± 5% radiochemical yield and 102 ± 15 GBq/μmol molar activity. Biodistribution in healthy rats demonstrated the brain penetration with low penetration of radiometabolites. However, E to Z isomerization observed in plasma hampers further investigations of this family of molecules and requires complementary data on the in vivo behavior of the Z isomer.

Virus-like particles constitute versatile vectors that can be used as vaccine platforms in many fields from infectiology and more recently to oncology. We previously designed non-infectious adenovirus-inspired 60-mer dodecahedric virus-like particles named ADDomers displaying on their surface either a short epitope or a large tumor/viral antigen. In this work, we explored for the first time the immunogenicity of ADDomers exhibiting melanoma-derived tumor antigen/epitope and their impact on the features of human dendritic cell (DC) subsets. We first demonstrated that ADDomers displaying tumor epitope/antigen elicit a strong immune-stimulating potential of human DC subsets (cDC2s, cDC1s, pDCs), which were able to internalize and cross-present tumor antigen, and subsequently cross-prime antigen-specific T-cell responses. To further limit off-target effects and enhance DC targeting, we engineered specific motifs to de-target epithelial cells and improve DCs' addressing. The improved engineered platform making it possible to display large antigen represents a tool to overcome the barrier of immune allele restriction, broadening the immune response, and paving the way to its potential utilization in humans as an off-the-shelf vaccine.

Background: As the COVID-19 pandemic progressed, disinformation, fake news, and conspiracy theories spread through many parts of society. However, the disinformation spreading through social media is, according to the literature, one of the causes of increased COVID-19 vaccine hesitancy. In this context, the analysis of social media posts is particularly important, but the large amount of data exchanged on social media platforms requires specific methods. This is why machine learning and natural language processing models are increasingly applied to social media data., Objective: The aim of this study is to examine the capability of the CamemBERT French-language model to faithfully predict the elaborated categories, with the knowledge that tweets about vaccination are often ambiguous, sarcastic, or irrelevant to the studied topic., Methods: A total of 901,908 unique French-language tweets related to vaccination published between July 12, 2021, and August 11, 2021, were extracted using Twitter's application programming interface (version 2; Twitter Inc). Approximately 2000 randomly selected tweets were labeled with 2 types of categorizations: (1) arguments for (pros) or against (cons) vaccination (health measures included) and (2) type of content (scientific, political, social, or vaccination status). The CamemBERT model was fine-tuned and tested for the classification of French-language tweets. The model's performance was assessed by computing the F1-score, and confusion matrices were obtained., Results: The accuracy of the applied machine learning reached up to 70.6% for the first classification (pro and con tweets) and up to 90% for the second classification (scientific and political tweets). Furthermore, a tweet was 1.86 times more likely to be incorrectly classified by the model if it contained fewer than 170 characters (odds ratio 1.86; 95% CI 1.20-2.86)., Conclusions: The accuracy of the model is affected by the classification chosen and the topic of the message examined. When the vaccine debate is jostled by contested political decisions, tweet content becomes so heterogeneous that the accuracy of the model drops for less differentiated classes. However, our tests showed that it is possible to improve the accuracy by selecting tweets using a new method based on tweet length., (©Romy Sauvayre, Jessica Vernier, Cédric Chauvière. Originally published in JMIR Medical Informatics (https://medinform.jmir.org), 17.05.2022.)

Objective: The objectives of the study are to describe the obstetric outcomes associated with massive perivillous fibrin deposition (MFD) compared with a control series and to determine if outcome differs according to the extent of fibrin deposition., Method: Retrospective case-control study based on placentas analyzed over a consecutive 12-year period. MFD was considered severe if it extended over more than 50% of the placenta and moderate between 25% and 50%., Results: During the study period, MFD was observed on 71 placentas, 39 severe and 32 moderate. Compared with the 142 control women, the 39 women with severe MFD more often had histories of autoimmune disease and intrauterine fetal death. The case women with MFD were associated with elevated levels of maternal alpha-fetoprotein and with a high risk of severe growth restriction and/or intrauterine death. Compared with the infants with moderate MFD, those with severe MFD had also more abnormal umbilical artery Doppler velocimetry findings and more often intrauterine deaths and lower birthweights., Conclusion: Regardless of their extent, MFD that covered at least 25% of the placenta was almost always accompanied by severe growth restriction and by a high risk of intrauterine fetal death. Moreover, severe MFD tend to be associated with autoimmune diseases of the mothers, and pregnancies show more often a pathologic Doppler of the umbilical arteries and more often intrauterine fetal death that the moderate form. © 2017 John Wiley & Sons, Ltd., (© 2017 John Wiley & Sons, Ltd.)

The aim of this study was to analyze the displacements of center of pressure (COP) using an in-shoe recording system (F-Scan) before and after motor nerve block and neurotomy of the tibial nerve in spastic equinovarus foot. Thirty-nine patients (age 45 ± 15 yr) underwent a motor nerve block; 16 (age 38 ± 15.2 yr) had tibial neurotomy, combined with tendinous surgery (n = 9). The displacement of the COP (anteroposterior [AP], lateral deviation [LD], posterior margin [PM]) was compared between paretic and nonparetic limbs before and after block and surgery. At baseline, the nonparetic limb had a higher AP (17.3 vs 12.3 cm, p < 0.001) and LD (4.0 vs 3.3 cm, p = 0.001) and a smaller PM (2.9 vs 4.7 cm, p = 0.001). For the paretic limb, a significant increase of AP was observed after block (13.5 vs 12.3 cm, p = 0.02) and after surgery (13.7 vs 12.3 cm, p = 0.03). A significant decrease of PM was observed after surgery (4.5 vs 3.3 cm, p < 0.001) with no more difference between two limbs (2.8 vs 3.3 cm; p = 0.44). This study shows that the F-Scan system can be used to quantify impairments and be useful to evaluate the effects of treatment for spastic foot. It suggests that changes in AP displacement following block may predict the effects of neurotomy.