Engineering of dense arrays of Vertical Si1-xGexnanostructures.

Vertical nanostructure technologies are becoming more important for the down scaling of nanoelectronic devices such as logic transistors or memories. Such devices require dense vertical nanostructured channel arrays (VNCA) that can be fabricated through a top-down approach based on group IV materials. We present progresses on the top-down fabrication of highly anisotropic and ultra-dense Si1-xGex(x= 0, 0.2, 0.5) VNCAs. Dense nanowire and nanosheet patterns were optimized through high resolution lithography and transferred onto Si1-xGexsubstrates by anisotropic reactive ion etching with a fluorine chemistry. The right gas mixtures for a given Ge content resulted in perfectly vertical and dense arrays. Finally we fabricated oxide shell/SiGe core heterostructures by dry- and wet-thermal oxidation and evaluated their applicability for nanostructure size engineering, as already established for silicon nanowires. The impact of the nanostructured shape (wire or sheet), size and Ge content on the oxide growth were investigated and analysed in detail through transmission electron microscopy.

Acute Myocarditis after COVID-19 vaccination: A case report.

INTRODUCTION: The etiology of myocarditis often remains undetermined. A large variety of infectious agents, systemic diseases, drugs, and toxins can cause the disease. We report the case of a 19-year-old man who developed myocarditis three days after Pfizer-BioNTech COVID-19 booster vaccination. CASE REPORT: A 19-year-old man, presenting with troponin-positive acute chest pain, was referred to our department. He had received the Pfizer-BioNTech COVID-19 vaccine three days prior to his admission. The diagnosis of acute myocarditis was confirmed by cardiovascular magnetic resonance imaging. Patient hemodynamic status remained stable during hospitalization. The left ventricular ejection fraction was preserved during hospital stay and at one-month follow-up. We found no evidence for another infectious or autoimmune etiology. CONCLUSION: Although imputability of the vaccine cannot be formally established on the basis of this case report, the findings raise the possibility of an association between mRNA COVID-19 vaccination and acute myocarditis.

[Particularities of African descent patient's electrocardiogram]. / Particularités de l'électrocardiogramme du patient d'origine Africaine.

Particularities of African descent patient's electrocardiogram have been described for many years. Variations such as higher QRS voltage, early repolarization pattern, precordial T-wave inversion and anterior ST segment elevation associated with T-wave inversion are more frequently observed. Ignorance of these variations can lead to misdiagnosis or therapeutic negligence. We present the electrocardiographic particularities attributed to the patient of African origin.

[Acute autoimmune myocarditis secondary to Graves' disease: a case report]. / Myocardite aiguë auto-immune secondaire à une maladie de Basedow : à propos d'un cas.

INTRODUCTION: Interactions between heart and thyroid are strong. Main cardiac complications of Graves' disease are supra-ventricular tachycardia or high output cardiac failure, without real myocardial involvement. OBSERVATION: A 40-year-old man with history of refractory Graves' disease was hospitalized for an acute chest pain with elevated cardiac biomarkers and normal coronarography. Acute myocarditis was confirmed by cardiac MRI. We found no evidence for an infectious etiology. We retained the hypothesis of acute autoimmune myocarditis in the context of active Graves' disease. CONCLUSION: Acute myocarditis is an exceptional complication of Graves' disease, with most likely an autoimmune mechanism. Possible occurrence of fulminant rhythmic or hemodynamic complications justify minimal cardiological check-up before introducing beta blockers.

[Cardiovascular complications of doping products]. / Complications cardiovasculaires des produits dopants.

Doping is the use of a substance that artificially increases an individual's physical ability for competition purpose. Products and methods used in doping are not without risk, especially at cardiovascular level. Here we review the most common doping substances in sport and their cardiovascular consequences.

[Inferior myocardial infarction complicated by complete heart block and cardiac arrest following a gadolinium injection: A case of Kounis syndrome]. / Infarctus du myocarde inférieur compliqué de bloc auriculo-ventriculaire complet et d'arrêt cardiocirculatoire dans les suites d'une injection de gadolinium : à propos d'une observation de syndrome de Kounis.

Kounis syndrome is an allergic acute coronary syndrome. It occurs on healthy or pathological arteries. Its complications, although often benign, can lead to cardiac arrest and death. Its triggering factors are multiple and include contrast products used in diagnostic imaging. We report the case of an 81 years old patient affected by hepatocellular carcinoma, who presented a type 2 Kounis syndrome with inferior myocardial infarction, complicated by cardiac arrest related to complete heart block following a gadoteric acid injection.