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This paper introduces the scalar DCC-HEAVY and DECO-HEAVY models for conditional variances and correlations of daily returns based on measures of realized variances and correlations built from intraday data. Formulas for multi-step forecasts of conditional variances and correlations are provided. Asymmetric versions of the models are developed. An empirical study shows that in terms of forecasts the scalar HEAVY models outperform the scalar BEKK-HEAVY model based on realized covariances and the scalar BEKK, DCC, and DECO multivariate GARCH models based exclusively on daily data.

Nowadays, intrusion detection systems based on deep learning deliver state-of-the-art performance. However, recent research has shown that specially crafted perturbations, called adversarial examples, are capable of significantly reducing the performance of these intrusion detection systems. The objective of this paper is to design an efficient transfer learning-based adversarial detector and then to assess the effectiveness of using multiple strategically placed adversarial detectors compared to a single adversarial detector for intrusion detection systems. In our experiments, we implement existing state-of-the-art models for intrusion detection. We then attack those models with a set of chosen evasion attacks. In an attempt to detect those adversarial attacks, we design and implement multiple transfer learning-based adversarial detectors, each receiving a subset of the information passed through the IDS. By combining their respective decisions, we illustrate that combining multiple detectors can further improve the detectability of adversarial traffic compared to a single detector in the case of a parallel IDS design., Comment: This is a preprint of an already published journal paper

Un homme de 65 ans, victime du COVID en mars 2020 y survit avec de lourdes séquelles fonctionnelles, notamment oculomotrices et vestibulaires. L'étiologie reste difficile. La démarche diagnostique est rendue compliquée en raison du contexte.

Resume Nous avons mis au point et rapportons les resultats preliminaires d’une nouvelle technique endoscopique de transfert de Whiteside dans les lesions chroniques depassees du moyen gluteal (tendon non ou partiellement reinserable et/ou involution graisseuse musculaire severe). Un transfert endoscopique du grand gluteal et/ou du tenseur du fascia lata est realise en complement de la reinsertion double rang du tendon moyen gluteal. Nous rapportons les resultats preliminaires d’une serie continue de 6 patients revus avec un recul minimum de 2 ans. Une patiente a eu un echec precoce. Deux patients n’ont pas ete ameliores sur les douleurs et la boiterie. Trois patients ont eu des resultats satisfaisants dont 2 avec disparition complete de la boiterie et des douleurs. Le transfert endoscopique de Whiteside combine a la reparation du tendon moyen gluteal donne des resultats mitiges sur la recuperation de la force d’abduction et la disparition de la boiterie de Trendelenburg.

There has been renewed interest in anterior cruciate ligament (ACL) repair procedures in the past decade. Even though ACL reconstruction is still considered the gold standard, ACL repair is an alternative in selected patients. However, the risk of failure owing to isolated ACL repair remains a concern. Intra-articular augmentation has been proposed to protect the repair during the healing period. In the same way, the protective effect of anterolateral ligament reconstruction on the ACL graft is increasingly recognized. We describe a combined ACL repair and anterolateral ligament reconstruction technique with a single-strand gracilis for the intra-articular portion and as an anterolateral graft to protect the ACL repair during the healing phase., Technique Video Video 1 Combined anterior cruciate ligament (ACL) repair and anterolateral ligament (ALL) reconstruction technique with a single-strand gracilis for the intra-articular portion and as an anterolateral graft to protect the ACL repair during the healing phase. The operation is performed on a proximal ACL tear in the right knee. The patient is placed supine, and standard arthroscopic portals are used. The gracilis tendon is harvested for use both as an intra-articular augmentation and for ALL reconstruction. The gracilis strand is passed from the tibia to the femur through bone tunnels, and after fixation of the intra-articular portion of the gracilis, the remaining ACL is sutured back to its femoral insertion. Reconstruction of the ALL is then performed using the gracilis strand emerging from the femoral tunnel.

Resume Introduction L’enclouage centromedullaire (ECM) est le traitement de reference des fractures diaphysaires de tibia. Les facteurs de risque de complications septiques et/ou mecaniques, et particulierement de pseudarthrose, restent mal connus, et imparfaitement rapportes. L’objectif de cette etude etait d’evaluer ces facteurs de complications, notamment concernant la pseudarthrose. Hypothese Le tabagisme actif et l’ouverture cutanee initiale sont des facteurs de risque de complications independants. Materiels et methodes Tous les patients pris en charge pour des fractures diaphysaires de tibia, fermees et ouvertes, par ECM en premiere intention, entre 2013 et 2018, etaient inclus dans cette serie. Etaient evalues les facteurs preoperatoires lies au patient et au mecanisme (âge, sexe, tabac, energie, ouverture cutanee), peroperatoires (espace interfragmentaire (EIC)) et postoperatoire (appui precoce ou retarde) et etaient etudiees leurs associations avec la survenue de complications, notamment de pseudarthrose. Une analyse uni- puis multivariee etait realisee. Un total de 184 patients ont ete inclus (âge moyen : 38,5 ± 17,6 (15–91), 72,2 % hommes). Resultats Une ou plusieurs complication(s) est/sont survenue(s) chez 28 (15,2 %) patients, et une pseudarthrose chez 15 (8,1 %) patients. Le tabac (OR : 7,93, IC 95 % [2,76–22,7]), l’EIC (OR : 4,92, IC 95 % [1,72–14,02]), et l’ouverture cutanee initiale (OR : 5,16, IC 95 % [1,62–16,43]) etaient des facteurs de risque significatifs de complications (p Discussion Le tabagisme actif, un large EIF et l’ouverture cutanee sont des facteurs de risque de complication postoperatoire apres ECM de fracture tibiale. Des strategies de prevention, et une information specifique pourraient etre mises en place pour ces sujets. Niveau de preuve IV ; etude retrospective monocentrique de cohorte.

INTRODUCTION: Vitamin K antagonists (VKA) and non-vitamin K oral antagonist anticoagulants (NOAC) are used in the clinic to reduce risk of thrombosis. However, they also exhibit vascular off-target effects. The aim of this study is to compare VKA and NOAC on atherosclerosis progression and calcification in an experimental setup.MATERIAL AND METHODS: Female Apoe-/- mice (age 12 weeks) were fed Western-type diet as control or supplemented with dabigatran etexilate or warfarin for 6 or 18 weeks. Vascular calcification was measured in whole aortic arches using µCT and [18 F]-NaF. Atherosclerotic burden was assessed by (immuno)histochemistry. Additionally, in vitro effects of warfarin, thrombin, and dabigatran on primary vascular smooth muscle cells (VSMC) were assessed.RESULTS: Short-term treatment with warfarin promoted formation of atherosclerotic lesions with a pro-inflammatory phenotype, and more rapid plaque progression compared with control and dabigatran. In contrast, dabigatran significantly reduced plaque progression compared with control. Long-term warfarin treatment significantly increased both presence and activity of plaque calcification compared with control and dabigatran. Calcification induced by warfarin treatment was accompanied by increased presence of uncarboxylated matrix Gla protein. In vitro, both warfarin and thrombin significantly increased VSMC oxidative stress and extracellular vesicle release, which was prevented by dabigatran.CONCLUSION: Warfarin aggravates atherosclerotic disease activity, increasing plaque inflammation, active calcification, and plaque progression. Dabigatran lacks undesired vascular side effects and reveals beneficial effects on atherosclerosis progression and calcification. The choice of anticoagulation impacts atherosclerotic disease by differential off target effect. Future clinical studies should test whether this beneficial effect also applies to patients.

La fonction vestibula ire est en symbiose avec la vergence oculomotrice. La sensation de vertige peut être liée à des troubles de vergence et, à l'inverse, des pathologies vestibulaires peuvent affecter la vergence. Une récente étude menée sur des patients vertigineux vient consolider cette hypothèse et apporter ainsi un élément clinique supplémentaire pour étayer le caractère multifactoriel de l'asthénopie vestibulaire .Treize patients atteints de vertige, âgés de 30 à 62 ans, ont été étudiés . Une évaluation avec mesure objective de la vergence a été réalisée avec vidéo­ oculographie. Quatre séances de rééducation des vergences ont été réalisées.Une évaluation a été faite un mois plus tard. L'évaluation initiale a révélé des problèmes d'amplitude et/ou de vitesse ou d'inconstance des vergences .Après réadaptation, une amélioration de la qualité des vergences a été observée chez les patients. Les patients ont fait état de bénéfices en termes d'assurance lors des déplacements dans l'espace. Les résultats obtenus confirment l'hypothèse d'une symbiose entre la vergence et la fonction vestibulaire , et l'intérêt d'une réhabilitation de la vergence après une affection ou une asthénopie vestibulaires . © 2021 Elsevier Masson SAS. Tous droits réservés.