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In-flight flux self-calibration procedure for cosmological surveys
No full textSpectroscopic surveys in astrophysics and cosmology require an accurate knowledge of the non-uniformity in the transmission of light introduced by the telescope optics, which yields a non-uniform response all over the focal plane.
In this work, we report a preliminary study on the in-flight flux self-calibration procedure and we characterize the expected precision on the reconstruction of the response function for a typical astrophysical surve
The beneficial impact of surface oxidation on electrochemical reactions with GaSe nanosheets
No full textGallium selenide (GaSe) is a van der Waals semiconductor widely used for optoelectronic devices, whose performances are dictated by bulk properties, including band-gap energy. However, recent experimental observations that the exfoliation of GaSe into atomically thin layers enhances performances in electrochemistry and photocatalysis have apparently opened new avenues for its applications in the fields of energy and catalysis. Here, with surface-science experiments and density functional theory (DFT) we study the oxidation of GaSe into β-Ga2O3. The oxidation driven by Se vacancies, created in the exfoliation process, plays a pivotal role in the catalytic process
Optimization of the theoretical dose distribution in the “Spread Out Bragg Peak” (SOBP) region in proton therapy by means of semi-analytical techniques
No full textProton therapy uses proton beams to destroy cancer cells. Since the energy deposition of protons peaks at the end of the trajectory (Bragg peak), healthy tissues close to the target are partially spared. In clinical practice, beams of different energies are composed to obtain a broadened peak (SOBP, Spread Out Bragg Peak) to treat the entire lesion region in a uniform manner. In the framework of the
TOP-IMPLART project (linear accelerator for proton therapy under construction at ENEA-Frascati), we present a semi-analytical method that allows to optimize SOBP uniformity for two different energy-modulation techniques, passive and active
A novel targeting approach for melanoma cancer treatment based on photodynamic therapy
No full textPhotosensitizing molecules have been at the basis of photodynamic therapy (PDT) since its early development in the 1950s. The therapy is a selective treatment method based on the administration of a photosensitizer to diseased cells: when irradiated with visible light of suitable wavelength, the photoactivated molecule starts a cascade of molecular transitions leading to cytotoxic effects in the targeted cells. The achievement of effective bio-compounds with photosensitizing capabilities and increased selectivity towards specific tumors is at the heart of the current research in the field. The aim of the herein project is to create an all-in-one multifunctional bio-molecule to be used in PDT treatments for melanoma cancer cells and holding targeting, imaging and photosensitizing potential
Analysis of time correlations for high sensitivity measurements
No full textThis work illustrates the development of an alpha spectroscopy system dedicated to the measurement of surface contaminations in materials used for low-background radioactive experiments. The system described is sensitive to trace levels of natural radionuclides. The operating principle is based on the simultaneous measurement of time and energy for each detected particle. A dedicated selection algorithm is developed to identify events in defined temporal relationships, so as to highlight cascade decays in natural radioactive chains. The shown results highlight the potential of the technique in reducing the radioactive background and revealing contamination otherwise not observable with usual analysis technique
Sarcoidosis Versus Lymphoma?
Get PDFAn association between lymphoma and sarcoidosis was first suggested in 1960. We report a case of sarcoidosis-lymphoma syndrome, which is a diagnostically challenging condition. We conclude that an associated lymphoma should be considered in all patients with suspected sarcoidosis, especially those who do not respond to treatment or who present with persistent haematological abnormalities. Splenomegaly should prompt splenectomy to rule out lymphoma if a less invasive approach has failed to confirm the diagnosis
Pleural Effusion Related to Chronic Hepatitis B Virus Reactivation: A Rare Association
Get PDFDespite worldwide vaccination campaigns, hepatitis B virus (HBV) infection remains a major public health problem. The natural history ranges from asymptomatic infection to severe liver injury or failure, chronic complications or reactivation episodes. The effects of HBV on the organism are immunomediated, possibly triggering extrahepatic manifestations. Since 1971, only a few cases of pleural effusion related to HBV infection have been described. We report HBV-associated pleural effusion occurring during a viral reactivation episode. Antiviral treatment directed towards pleural effusion related to HBV infection should be dictated by underlying liver disease severity and not pleural effusion severit
Autoimmune Hepatitis–Primary Biliary Cholangitis Overlap Syndrome Triggered by COVID-19
Get PDFCOVID-19, caused by severe acute respiratory syndrome coronavirus 2 infection, has caused the ongoing global pandemic. Initially considered a respiratory disease, it can manifest with a wide range of complications (gastrointestinal, neurological, thromboembolic and cardiovascular) leading to multiple organ dysfunction. A range of immune complications have also been described. We report the case of a 57-year-old man with a medical history of hypertension, prediabetes and beta thalassemia minor, who was diagnosed with COVID-19 and subsequently developed fatigue and arthralgias, and whose blood work showed hyperferritinemia, elevated liver enzymes (AST/ALT/GGT), hypergammaglobulinemia, anti-smooth muscle antibody, anti-mitochondrial antibody, and anti-double-stranded DNA antibodies. The patient was diagnosed with autoimmune hepatitis–primary biliary cholangitis overlap syndrome triggered by COVID-19. To our knowledge, this is the first such case reported
Congenital Inferior Vena Cava Agenesis with Ulceration and Deep Vein Thrombosis
Get PDFObjectives:
This is one of the few case reports of congenital inferior vena cava atresia (IVCA) with extensive bilateral lower extremity ulcers.
Background:
IVCA is a congenital anomaly characterized by poor venous return in the lower extremities with increased risk of deep vein thrombi (DVTs) and, rarely, non-healing ulcers.
Results:
A 45-year-old woman with history significant for DVTs presented with extensive bilateral lower extremity ulcers, and a CT scan revealed congenital IVCA. Oedema management, DVT prevention, routine wound care and skin grafts resolved the ulcers.
Conclusion:
Congenital venous abnormalities should be included in the differential diagnosis of multiple unprovoked DVTs and non-healing ulcers
What are the Clinical Implications of a Positive RT-PCR Test 6 Months after a Mild SARS-CoV-2 Infection?
Get PDFWe present the case of an 84-year-old female patient hospitalized for surgical treatment of a hip fracture who re-tested positive for SARS-CoV-2 with an RT-PCR nasopharyngeal swab approximately 6 months after presenting mild respiratory symptoms with confirmed COVID-19 in April 2020. We discuss the possibility of reinfection, long-term viral shedding and residual positivity, the limitations of RT-PCR swab tests, and the necessity for new testing methods as the COVID-19 pandemic spreads and long-lasting immunity is uncertain