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Electrochemical exfoliation of graphite in H2SO4, Li2SO4 and NaClO4 solutions monitored in-situ by Raman microscopy and spectroscopy
Get PDFThe electrochemical exfoliation of graphite is one of the cheapest and most tunable industrial techniques to produce graphene nanosheets with tunable degree of oxidation and solubility. Anodic oxidation allows high-yield production of electrochemically exfoliated graphene oxide (EGO) in either acids or salt solutions, with the key role played by ions electrochemically driven in between the graphene sheets. This chemical intercalation is followed by a mesoscale mechanical exfoliation process, which is key for the high yield of the process, but which is still poorly understood. In this work, we use Raman spectroscopy to simultaneously monitor the intercalation and oxidation processes taking place on the surface of highly ordered pyrolytic graphite (HOPG) during electrochemical exfoliation. The mechanism of EGO formation in either acidic (0.5 M H2SO4) or neutral (0.5 M Li2SO4) electrolytes through blistering and cracking steps is discussed and described. This process is compared also to non-destructive intercalation of graphite in an organic electrolyte (1 M NaClO4 in acetonitrile). The results obtained show how high exfoliation yield and low defectivity shall be achieved by the combination of efficient, non-destructive intercalation followed by chemical decomposition of the intercalants and gas production
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Get PDFLe numerose vittime del coronavirus impongono anche riflessioni filosofiche ed etiche poiché rimandano all’indagine sull’uomo, ai suoi valori, alle sue esigenze in ogni ambito del vivere, con particolare riguardo alla salute
La Storia dell’Architettura in America Latina. Enrico Tedeschi in Argentina
Get PDFEuropean culture in Latin America has undoubtedly been fundamental to initiating innovative and technological transfer processes that have contributed to the progress of nations. This is especially evidenced by the many works carried out in the different fields of knowledge in which so many researchers and professionals have tried their hand at it, who for different reasons have had to leave their country to find acceptance in often very distant lands. However, the meeting of different cultures has fostered the development of new activities and encouraged the contribution of creativity in favor of unconventional training and production processes.
In continuing the path initiated by the international research Italian Diaspora in the world, this volume is a new tribute to the many Italians who have distinguished themselves overseas, especially in Latin America, building extraordinary opportunities and opening up new professional perspectives. This is the case of the Italian architect Enrico Tedeschi (1910-1978) who left Italy in 1948 to reach Argentina in order to realize the expected academic dreams. A complex experience like many but from which began a new research path that focused a lot on the role of the history of architecture in the formation of the architect who, from the second half of the twentieth century, has obtained remarkable feedback throughout the Latin American area.
The pages of this book, not exhaustive of a very interesting but broad theme, aim to open a dialogue on how the treatment of the history of architecture in Latin America is now more fundamental than ever to start new training paths and to stimulate knowledge of the past to better build the future
Cardiopulmonary Resuscitation Induced Consciousness - A Case Report in an Elderly Patient
Get PDFCardiopulmonary resuscitation-induced consciousness is a rarely described and often misunderstood phenomenon, although it can be encountered. High quality cardiopulmonary resuscitation (CPR) may lead a patient to recover consciousness while in cardiac arrest. The authors present the case of an 89-year-old male patient who received CPR after a cardiac arrest. Spontaneous movements during CPR were noted and prompted several CPR interruptions. These movements immediately stopped during chest compression pauses. Physical restraint was used in order to be able to continue with the CPR algorithm, but sedation may be the best approach. Guidelines on how to identify and manage these cases need to be developed
An Overlapping Case of Miller Fisher Syndrome and the Pharyngeal-Cervical-Brachial Variant of Guillain-Barré Syndrome
Get PDFA 55 years-old Caucasian male presented initially in the emergency room reporting myalgia, chills and fever. Physical exam and laboratory tests were unremarkable and he was discharged with symptomatic care. He returned to our ER two weeks later reporting dizziness, loss of balance, blurred vision, mild dysarthria and bilateral hand paresthesia. On examination he presented complete bilateral ophthalmoplegia, mild dysarthria, left finger-to-nose dysmetria, ataxia, areflexia and bilateral hand hypoesthesia without fever. Blood tests and head computed tomography were normal. The patient was admitted to the Internal Medicine department. On second day inwards the patient presented dysphagia. Head magnetic resonance angiogram showed no signs of ischemia or vascular disease and a lumbar puncture was performed but no pleocytosis, albumin-cytological dissociation or hypoglycorrhachia was present. Despite the normal results we suspected of a Guillain–Barré syndrome variant, and started treatment with intravenous immunoglobulin (IVIG) in a dose of 400mg per kilogram and continued for five days with immediate neurological improvement. We present a rare overlapping case of Miller Fisher syndrome and Pharyngeal-Cervical-Brachial variant of Guillain–Barré syndrome
Intellectual Disability, Falls and Gait Disturbances: A Misdiagnosis
Get PDFWe report the case of a 27-year-old man presenting with slowly progressive extrapyramidal dysfunction and learning disability considered to have a syndromic intellectual disability. The re-evaluation of the clinical features and the investigations performed led to the diagnosis of atypical pantothenate kinase-associated neurodegeneration (PKAN)
Type B Interrupted Aortic Arch with a Patent Ductus Arteriosus in an Adult Presenting with Secondary Polycythaemia
Get PDFInterrupted aortic arch (IAA) is an extremely rare congenital cyanotic heart disease characterized by complete disruption between the ascending and descending aorta. A patent ductus arteriosus (PDA) or other collateral pathways provide blood flow to the distal descending aorta. Mortality is extremely high at early infancy, particularly after the closure of ductus arteriosus. Survival and presentation in adulthood are extremely rare. Here we illustrate a rare case of type B interrupted aortic arch in an adult who presented with secondary polycythaemia. The blood supply to descending aorta and beyond is almost solely by a patent ductus arteriosus. The case demonstrates the value of multimodality imaging including CT and MRI for diagnosis and treatment planning in these patients
The Dark Purple Side of Ceftriaxone: A Case Report on Leucocytoclastic Vasculitis
Get PDFWe present a case of an 85-year-old woman diagnosed with uncomplicated pyelonephritis, who was treated with intravenous ceftriaxone. Her chronic medications were phenprocoumon, diltiazem and bisoprolol. During the infectious phase, the patient presented tachycardia – despite high-dose beta-blocker treatment – and developed left acute heart failure, with acute renal failure (pre-renal origin). After introduction of furosemide diuretic therapy, clinical conditions improved and better control of the volemic status and heart rate was achieved. Several days after ceftriaxone and digoxin therapy initiation, worsening multiple non-blanching palpable purpuric lesions with bullae and papules, limited to the lower extremities, were noted. Skin biopsy was performed and a diagnosis of leucocytoclastic vasculitis, with associated panniculitis, was made. Ceftriaxone was discontinued and systemic corticosteroids were introduced, with a clear improvement in the cutaneous condition
Tetraparesis with Major Hypokalaemia and Rhabdomyolysis Induced by Chronic Liquorice Ingestion
Get PDFChronic ingestion of liquorice induces a syndrome with findings similar to those for primary hyperaldosteronism. This is characterized by hypokalaemia, hypertension, metabolic alkalosis and suppression of the renin-aldosterone system.
We describe a 30-year-old woman who, with a plasma potassium level of 1.5 mmol/l, presented with tetraparesis and severe rhabdomyolysis (CK up to 35,460 U/l). She admitted to a daily consumption of nearly 300 g of liquorice sweets during the previous 6 months. This case emphasizes the importance of a detailed anamnesis, which is essential for diagnosis, avoids unnecessary and expensive investigations and reduces the duration of hospitalization
Arterial Mesenteric Thrombosis as a Complication of SARS-CoV-2 Infection
Get PDFA 52-year-old patient with SARS-CoV-2 was diagnosed with interstitial pneumonia and treated with darunavir/ritonavir, hydroxychloroquine, azithromycin and low molecular weight heparin (LMWH). After LMWH cessation, he developed superior mesenteric arterial thrombosis. An abdominal CT scan showed arterial thrombosis of vessels efferent of the superior mesenteric artery with bowel distension.
COVID-19 may predispose to venous and arterial thromboembolism. Anticoagulation prophylaxis should be considered in hospitalized patients with COVID-19, and potential thromboembolism investigated in each symptomatic patient affected by SARS-CoV-2