Scale Invariant Cosmology

An attempt is made here to extend to the microscopic domain the scale invariant character of gravitation - which amounts to consider expansion as applying to any physical scale. Surprisingly, this hypothesis does not prevent the redshift from being obtained. It leads to strong restrictions concerning the choice between the presently available cosmological models and to new considerations about the notion of time. Moreover, there is no horizon problem and resorting to inflation is not necessary.Comment: TeX, 20 page

Genèse de l'État haïtien (1804-1859)

Pendant la domination espagnole en Amérique Latine du xvie au xixe siècle, l'Espagne était, en tant que métropole, l'interlocutrice naturelle des autres nations européennes. Tout ce qui était lié à l'itinéraire Europe-Amérique hispanique passait par la couronne espagnole, ou du moins c'est ce qu'elle prétendait : les idées, les arts, les institutions, les marchandises, les nouvelles, les voyageurs, etc. Cependant, après les guerres d'indépendance qui eurent heu au début du xixe siècle et qui furent la conséquence directe de l'affaiblissement de la monarchie espagnole après l'invasion du pays par les troupes de Napoléon Ier, les pays libérés du joug espagnol établirent de nouvelles relations avec l'Europe, fixant leurs propres règles et laissant voir leurs préférences pour certaines nations européennes

Assessment of fenestrated Anaconda stent graft design by numerical simulation: Results of a European prospective multicenter study

Objective: A crucial step in designing fenestrated stent grafts for treatment of complex aortic abdominal aneurysms is the accurate positioning of the fenestrations. The deployment of a fenestrated stent graft prototype in a patient-specific rigid aortic model can be used for design verification in vitro, but is time and human resources consuming. Numerical simulation (NS) of fenestrated stent graft deployment using the finite element analysis has recently been developed; the aim of this study was to compare the accuracy of fenestration positioning by NS and in vitro. Methods: All consecutive cases of complex aortic abdominal aneurysm treated with the Fenestrated Anaconda (Terumo Aortic) in six European centers were included in a prospective, observational study. To compare fenestration positioning, the distance from the center of the fenestration to the proximal end of the stent graft (L) and the angular distance from the 0° position (C) were measured and compared between in vitro testing (L1, C1) and NS (L2, C2). The primary hypothesis was that ΔL (|L2 – L1|) and ΔC (|C2 – C1|) would be 2.5 or less mm in more than 80% of the cases. The duration of both processes was also compared. Results: Between May 2018 and January 2019, 50 patients with complex aortic abdominal aneurysms received a fenestrated stent graft with a total of 176 fenestrations. The ΔL and ΔC was 2.5 mm or less for 173 (98%) and 174 (99%) fenestrations, respectively. The NS process duration was significantly shorter than the in vitro (2.1 days [range, 1.0-5.2 days] vs 20.6 days [range, 9-82 days]; P < .001). Conclusions: Positioning of fenestrations using NS is as accurate as in vitro and could significantly decrease delivery time of fenestrated stent grafts

L’hôpital en restructuration

Les besoins de la population en matière de soins de santé et les pratiques cliniques évoluent dans un contexte hospitalier que d’aucuns jugent en pleine restructuration. Au cœur de toutes les grandes réformes politiques, en France comme au Québec, la réorganisation du système de santé est annoncée partout comme la priorité qui devrait permettre de résoudre tous les maux. Pourtant, si cette volonté politique de changement est clairement affichée, il reste que les stratégies de mise en œuvre sont souvent mal accueillies par les médecins et le personnel soignant qui doivent composer au quotidien avec un manque flagrant de ressources. Dans cet ouvrage, les restructurations ne sont pas considérées comme une simple solution miraculeuse apportée par les gestionnaires ou une réponse rationnelle imposée par les exigences de la pratique clinique. En présentant le paysage institutionnel de la France et du Québec, les auteurs adoptent résolument une approche qui enrichit notre compréhension des changements structurels. Les transformations y sont analysées sur le plan national et celui des dynamiques locales, pointant les singularités et les problèmes spécifiques de ressources, les initiatives individuelles et collectives, les logiques professionnelles qui déterminent le déclenchement et les trajectoires de restructuration. Avec cette réflexion rigoureuse et approfondie sur le dispositif hospitalier, une nouvelle étape est franchie qui permet l’émergence de nouveaux modèles pour penser les restructurations

Computed Tomography-Aortography Versus Color-Duplex Ultrasound for Surveillance of Endovascular Abdominal Aortic Aneurysm Repair

International audienceBackground Color-duplex ultrasonography (DUS) could be an alternative to computed tomography-aortography (CTA) in the lifelong surveillance of patients after endovascular aneurysm repair (EVAR), but there is currently no level 1 evidence. The aim of this study was to assess the diagnostic accuracy of DUS as an alternative to CTA for the follow-up of post-EVAR patients. Methods Between December 16, 2010, and June 12, 2015, we conducted a prospective, blinded, diagnostic-accuracy study, in 15 French university hospitals where EVAR was commonly performed. Participants were followed up using both DUS and CTA in a mutually blinded setup until the end of the study or until any major aneurysm-related morphological abnormality requiring reintervention or an amendment to the follow-up policy was revealed by CTA. Database was locked on October 2, 2017. Our main outcome measures were sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratios of DUS against reference standard CTA. CIs are binomial 95% CI. Results This study recruited prospectively 659 post-EVAR patients of whom 539 (82%) were eligible for further analysis. Following the baseline inclusion visit, 940 additional follow-up visits were performed in the 539 patients. Major aneurysm-related morphological abnormalities were revealed by CTA in 103 patients (17.2/100 person-years [95% CI, 13.9–20.5]). DUS accurately identified 40 patients where a major aneurysm-related morphological abnormality was present (sensitivity, 39% [95% CI, 29–48]) and 403 of 436 patients with negative CTA (specificity, 92% [95% CI, 90–95]). The negative predictive value and positive predictive value of DUS were 92% (95% CI, 90–95) and 39% (95% CI, 27–50), respectively. The positive likelihood ratio was 4.87 (95% CI, 2.9–9.6). DUS sensitivity reached 73% (95% CI, 51–96) in patients requiring an effective reintervention. Conclusions DUS had an overall low sensitivity in the follow-up of patients after EVAR, but its performance improved meaningfully when the subset of patients requiring effective reinterventions was considered. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01230203

One-year results of the INSIGHT study on endovascular treatment of abdominal aortic aneurysms

Objective: Endovascular repair of abdominal aortic aneurysms (AAAs) using the INCRAFT AAA stent graft system was safe and effective in regulatory approval studies. We herein report on the 1-year results of a real-world clinical study.Methods: The INSIGHT study is a multi-center, prospective, open label, post-approval study conducted to continually evaluate the safety and performance of the INCRAFT System. Between 2015 and 2016, 150 consecutive patients with AAA at 23 centers in Europe were treated with the device in routine clinical practice. The primary endpoint was freedom from major adverse events (MAEs), namely death, myocardial infarction, cerebrovascular accident, and renal failure, within 30 days of the index procedure. End point data were assessed by a core laboratory. The secondary end points included technical success at the conclusion of the procedure and clinical success.Results: All 150 patients studied (mean age, 73.6 +/- 8.0 years; 89.3% men) met the primary end point without MAEs at 30-day follow-up. Technical success was achieved in 99.3% of patients without stent fractures at 30 days. Among the 146 patients eligible for 1-year follow-up, the MAE rate was 8.2% (ie, 12 patients suffered 13 MAEs: cerebrovascular accident in 8, myocardial infarction in 1, and 4 died, resulting in a 2.7% all-cause mortality rate). There were no reports of new onset renal failure requiring dialysis. Only 2.7% of patients had type I endoleak, and no type III endoleaks were identified through 1 year. The rate of clinical success at 1 year was 91.8%.Conclusions: The 1-year results of this multicenter real-world study underscore the safety and effectiveness of endo-vascular treatment of AAA with the INCRAFT System in routine clinical practice