Scientific Open-access Literature Archive and Repository
Not a member yet
16397 research outputs found
Sort by
An Acute Blue Finger: A Case of Achenbach’s Syndrome
Get PDFAchenbach’s syndrome, also known as paroxysmal finger haematoma, is a rare condition that results in spontaneous bruising and pain in one or more fingers. Despite its benign and self-limiting course, the remarkable clinical presentation can suggest serious vascular and haematological disease leading to unnecessary referrals and invasive investigations. The authors present the case of a 60-year-old woman with an acute painful and bruised finger. All other physical findings and investigations were normal, except for autoimmune thyroiditis. Based on the clinical presentation and course, the diagnosis of Achenbach’s syndrome was made and the symptoms resolved without treatment
Consider Nitrofurantoin as a Cause of Lung Injury
Get PDFNitrofurantoin-induced diffuse lung toxicity is well documented in the literature but is often misdiagnosed. We describe an 82-year-old female medicated with nitrofurantoin for the previous 2 years who was admitted for dyspnoea, dry cough and fatigue for 4 months. She was febrile and tachypnoeic and she presented with bilateral basal crackles, hypoxaemic respiratory failure and slightly elevated C-reactive protein levels. A chest radiograph showed bilateral air-space consolidation and interstitial infiltrates and the high-resolution computed tomography scan was evocative of a perilobular pattern of organising pneumonia (OP). Due to the clinical–radiological context, she was diagnosed with a presumable nitrofurantoin-induced OP. She was started on prednisolone 60 mg daily with a progressive improvement. It is important that clinicians are aware of the spectrum of side effects associated with nitrofurantoin so as to monitor patients
Aortic Dissection with Haemothorax Mimicking a Stroke
Get PDFAortic dissection is a life-threatening clinical emergency and a challenging diagnosis. Depending on its initial location, it may present with several symptoms with the most common being chest pain. We describe the case of a 62-year-old man admitted to the Emergency Department with acute neurological deficits and triaged for the stroke protocol. After unexpected findings on physical examination, other diagnostic hypotheses were evaluated, culminating in the diagnosis of aortic dissection with haemothorax mimicking a stroke
The Reversed Halo Sign: Not Such a Specific Sign of Organising Pneumonia
Get PDFThe reversed halo sign is defined as a focal rounded area of ground-glass opacity surrounded by a more or less complete ring of consolidation. It is a relatively rare sign and initially considered a specific sign of organising pneumonia. We report the case of a 55-year-old female who was being followed-up in a pulmonology consultation due to a 6 mm nodule which required vigilance. On a re-evaluation chest CT scan, besides a stable 6 mm nodule, a 36 mm mass with the reversed halo sign was diagnosed. The presence of the reversed halo sign misled the multidisciplinary team into the diagnosis of organising pneumonia and initiation of corticotherapy was suggested. However, after further investigation, a final diagnosis of pulmonary tuberculosis was made. Even though this sign is relatively rare, and still considered an important clue to the diagnosis of organising pneumonia in immunocompetent patients, other causes must be excluded before starting treatment
Inferior Vena Cava Agenesis and Deep Vein Thrombosis: A Pharmacological Alternative to Vitamin K Antagonists
Get PDFInferior vena cava (IVC) agenesis is a rare congenital abnormality affecting the infrarenal segment, the suprarenal or the whole of the IVC. It has an estimated prevalence of up to 1% in the general population that can rise to 8.7% when abnormalities of the left renal vein are considered. Most IVC malformations are asymptomatic but may be associated with nonspecific symptoms or present as deep vein thrombosis (DVT). Up to 5% of young individuals under 30 years of age with unprovoked DVT are found to have this condition. Regarding the treatment of IVC agenesis-associated DVT, there are no standard guidelines. Treatment is directed towards preventing thrombosis or its recurrence. Low molecular weight heparin and oral anticoagulation medication, in particular vitamin K antagonists (VKAs) are the mainstay of therapy. Given the high risk of DVT recurrence in these patients, oral anticoagulation therapy is suggested to be pursued indefinitely. As far as we know, this is the first case reporting the use of a direct factor Xa inhibitor in IVC agenesis-associated DVT. Given VKA monitoring limitations, the use of a direct Xa inhibitor could be an alternative in young individuals with anatomical defects without thrombophilia, but further studies will be needed to confirm its efficacy and safety
Numerical simulations of high cross-helicity turbulence from 0.2 to 1 AU
Get PDFTurbulence in the fast stream of the solar wind is maintained despite the small compressibility and a dominance of outward-propagating fluctuations (z+ >z −), in contrast to its rapid decay in imbalanced homogenous MHD turbulence. We numerically study if the inhomogeneity introduced by solar wind expansion can be an effective source of z− that maintains turbulence. Starting at 0.2 AU with z− = 0, we obtain a damping with distance of z+ and a quasi-steady level of z−. Thez+ spectrum steepens with distance toward a −1.4 power-law at 1 AU, while the z− spectrum has a −5/3 power-law index at all distances. These properties are robust against variations of the input spectrum and expansion rate and are in agreement with in-situ data, suggesting that imbalanced turbulence can be maintained by expansion alone
Solar perturbations transits in Mercury exosphere
Get PDFThe link existing between the dayside Na exospheric patterns of Mercury and the solar wind-magnetosphere-surface interactions is investigated thanks to the synergy of Earth-based observations with the THEMIS solar telescope and the in-situ measurements of the Interplanetary Magnetic Field (IMF) and proton fluxes at the magnetic cusp regions by MESSENGER. Frequently, two-peak patterns of variable intensity are observed, located at high latitudes in both hemispheres. Occasionally, Na signal is instead diffused above the sub-solar region. In a special case, the Na signal is diffused above the subsolar region, when the MESSENGER data detect the transit of two Coronal Mass Ejections (CMEs). Na emission patterns results to be clearly related to the solar wind conditions at Mercury. Hence, the Na exospheric patterns, observed from ground, could be considered as a natural monitor of solar disturbances when transiting near Mercury
Self-consistent single-particle approximation to nuclear state densities at high excitation energy
Get PDFWe compute nuclear state densities for a number of magic and semimagic nuclei in the usual saddle point approximation within the framework of the grand-canonical formalism in an energy range where residual two-body interactions and collective effects can reasonably be neglected. The single-particle states used in the calculations are generated in a relativistic self-consistent mean field at finite temperature based on widely adopted effective interactions. Observed limits and
possible improvements of the adopted formalism are discussed
Impact of new results of the neutron capture cross section measurements for odd gadolinium isotopes on thermal-spectrum systems
Get PDFLight Water Reactors (LWRs) are frequently equipped with fuel pins in which UO2 is mixed with Gd2O3. Gd odd isotopes have extremely high neutron capture cross sections at very low energies and are currently used as burnable poisons. For this reason, ENEA put forward a research proposal for an improvement of the Gd nuclear data accuracy by means of new experiments to be done in the framework of the n TOF Collaboration. In 2016, new measurements were performed at the CERN, and subsequently ENEA in collaboration with IRSN, started to reevaluate the neutron capture cross sections (XSs) of Gd odd isotopes. This paper presents the results of Monte Carlo simulations performed with the new measured
data to estimate their impact on the criticality of a thermal-spectrum benchmark for which the value of keff is known. The outcomes demonstrate that the new data can produce a keff which is closer to the experimental one than that obtained using the currently available Gd evaluations
A Proton Recoil Telescope for the characterisation of the neutron beam at n TOF
Get PDFThe neutron induced fission cross section of 235U is extensively used as a reference for neutron fluence measurements in various applications. At intermediate energies, the 235U(n,f) cross section plays an important role also for fundamental nuclear physics. Despite its widespread use, no data exist on neutroninduced fission of 235U above 200 MeV. Hence, there is a clear and long-standing demand from the International Atomic Energy Agency (IAEA) to complement the experimental database from 20 MeV to 1 GeV. For this purpose at the neutron facility n TOF at CERN the measurement of 235U(n,f) cross section was planned
in October 2018, taking advantage of the intense neutron beam with a wide energy spectrum available in the experimental area. The cross section measurement will be performed relative to the elastic neutron-proton scattering, a very well known reaction generally accepted as primary reference. A prototype of the Proton Recoil
Telescope detector, that will be used to measure the incident neutron flux, has been built and tested at n TOF in 2017