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The fast proton-induced fission of 238U has been analyzed from the threshold up to 40 MeV. Fission observables and isotope production were analyzed using TALYS and our own programs. Fission process was described by Brosa model. In the fast proton interaction, residual nuclei by mean of different (p,p’), (p,xn), (p,xp), (p,xα) (x=1,2,…,n) and other processes are formed. In the case of 238U, residual nuclei can also fission, contributing to the investigated observables and isotope production. Comparing theoretical results and experimental data from literature, parameters of the optical potential, fission barrier and type of nucleus deformation were extracted. Cross sections and isotope yields obtained in neutron-induced fission process were compared with proton case and with EXFOR data.

Vasculitis refers to a group of rare conditions characterized by the inflammation of blood vessels, affecting multiple systems. It presents a diagnostic and therapeutic challenge due to its broad clinical manifestations. Vasculitis is classified based on the size of the affected vessels: small, medium, large, or variable-sized. Large vessel vasculitis (LVV), particularly giant cell arteritis (GCA) and Takayasu arteritis (TAK), has garnered attention due to its significant morbidity and mortality. Both conditions involve immune-mediated inflammation of the vascular wall, despite differing in epidemiology and presentation. Early identification is crucial to prevent complications like organ ischemia and hemorrhage. Diagnostic accuracy can be hampered by false negative results, making comprehensive investigation essential. Vascular imaging, including computed tomography angiography (CTA), ultrasound (US), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT), is key in diagnosing vasculitis, revealing vessel wall thickening and other suggestive features. This article reviews typical and atypical CT and CTA findings in LVV, discusses imaging modalities, and highlights their role in therapeutic management and prognosis. It emphasizes the importance of a multidisciplinary approach and the critical role of radiologists in improving patient outcomes in LVV. [ABSTRACT FROM AUTHOR]

Introduction. In the past, Streptococcus agalactiae was known to be associated with invasive infections in pregnant women and newborns. More recently, given a more appropriate antibiotic prophylaxis and treatment, the incidence among pregnant women and infants diminished. However, an increasing number of cases with infective endocarditis with Streptococcus agalactiae has been reported in the recent years in older patients with underlying comorbidities. Case report. An 80-year-old female patient presented with dyspnea, weight loss, fever, fatigue, chills, dry cough and bilateral lower limb edema. The work-up revealed complicated infective endocarditis with Streptococcus agalactiae on the native aortic valve with severe aortic regurgitation as a result of the valvular destruction and a metastatic spleen abscess. Antibiotic treatment was started with resolution of the fever and chills. The patient however developed congestive heart failure due to the valvular regurgitation. A decision was made to proceed urgently with aortic valve replacement and splenectomy, which were performed at the same time, followed by a good recovery. Results and discussion. An increasing number of cases with IE with GBS in elderly patients has been reported in the recent years, with high rate of complications and mortality. The underlying comorbidities are important risk factors for S. agalactiae IE. Considering our case, a patient in her eighties with significant abdominal surgical history and multiple medical conditions could be a typical host. Recovery after cardiac surgery is one of the most important indications of physical training. This includes patients post-coronary artery bypass grafting, after valve prosthetic replacement, after surgery for congenital diseases and after heart transplantation. Early mobilization is particularly important in avoiding immobility and cardiac deconditioning. Conclusions. Despite the fact that mortality in Group B Streptococcus endocarditis is 40%, a combined medical and surgical strategy individualized to the specific situation of each patient have led to a positive outcome in a number of cases. We present such a combined treatment approach in a case of complicated infective endocarditis with metastatic spleen abscess in an elderly patient. The aortic valve replacement and splenectomy were performed at the same time.

Fast neutron reactors, as a possible future solution on energy demand of human society, based on fission process of 238U, request new and reliable nuclear data necessary for new generation reactors design. Fission process induced by fast neutrons on 238U was investigated. Fission observables like cross sections and their uncertainties, fission fragment mass distribution, prompt neutrons emission, isomer ratios and other parameters were obtained by using Talys computer code or programs realized by authors. Then the production of isotopes like 135,133Xe, 99Mo, 131I, 89Y as well as yields of fissile nuclei were evaluated. Obtained theoretical evaluations are compared with existing experimental data.

NiO layers were grown on MgO(100), MgO(110), and MgO(111) substrates by plasma-assisted molecular beam epitaxy under Ni-flux limited growth conditions. Single crystalline growth with a cube-on-cube epitaxial relationship was confirmed by X-ray diffraction measurements for all used growth conditions and substrates except MgO(111). A detailed growth series on MgO(100) was prepared using substrate temperatures ranging from 20 °C to 900 °C to investigate the influence on the layer characteristics. Energy-dispersive X-ray spectroscopy indicated close-to-stoichiometric layers with an oxygen content of ≈ 47 at. % and ≈ 50 at. % grown under low and high O-flux, respectively. All NiO layers had a root-mean-square surface roughness below 1 nm, measured by atomic force microscopy, except for rougher layers grown at 900 °C or using molecular oxygen. Growth at 900 °C led to a significant diffusion of Mg from the substrate into the film. The relative intensity of the quasi-forbidden one-phonon Raman peak is introduced as a gauge of the crystal quality, indicating the highest layer quality for growth at low oxygen flux and high growth temperature, likely due to the resulting high adatom diffusion length during growth. The optical and electrical properties were investigated by spectroscopic ellipsometry and resistance measurements, respectively. All NiO layers were transparent with an optical bandgap around 3.6 eV and semi-insulating at room temperature. However, changes upon exposure to reducing or oxidizing gases of the resistance of a representative layer at elevated temperature were able to confirm p-type conductivity, highlighting their suitability as a model system for research on oxide-based gas sensing. [ABSTRACT FROM AUTHOR]

Nuclear data on Uranium isotopes are of crucial interest for new generation of nuclear reactors. Processes of interest are the nuclear reactions induced by neutrons and in this work mainly the capture and the fission process on 238U will be analyzed in a wide energy interval. For slow and resonant neutrons the many levels Breit – Wigner formalism is necessary. In the case of fast and very fast neutrons up to 200 MeV the nuclear reaction mechanism implemented in Talys will be used. The present evaluations are necessary in order to obtain the field of neutrons in the design of nuclear reactors and they are compared with experimental data from literature obtained from capture and (n,xn) processes.