Extra Spin-Wave mode in Quantum Hall systems. Beyond the Skyrmion Limit

We report on the observation of a new spin mode in a quantum Hall system in the vicinity of odd electron filling factors under experimental conditions excluding the possibility of Skyrmion excitations. The new mode having presumably zero energy at odd filling factors emerges at small deviations from odd filling factors and couples to the spin-exciton. The existence of an extra spin mode assumes a nontrivial magnetic order at partial fillings of Landau levels surrounding quantum Hall ferromagnets other then the Skyrmion crystal.Comment: 9 pages, 4 figure

Antiphased Cyclotron-Magnetoplasma Mode in a Quantum Hall System

An antiphased magnetoplasma (MP) mode in a two-dimensional electron gas (2DEG) has been studied by means of inelastic light scattering (ILS) spectroscopy. Unlike the cophased MP mode it is purely quantum excitation which has no classic plasma analogue. It is found that zero momentum degeneracy for the antiphased and cophased modes predicted by the first-order perturbation approach in terms of the {\it e-e} interaction is lifted. The zero momentum energy gap is determined by a negative correlation shift of the antiphased mode. This shift, observed experimentally and calculated theoretically within the second-order perturbation approach, is proportional to the effective Rydberg constant in a semiconductor material.Comment: Submitted to Phys. Rev.

Клинические аспекты применения искусственного интеллекта для интерпретации рентгенограмм органов грудной клетки

The review considers the possible use of artificial intelligence for the interpretation of chest X-rays by analyzing 45 publications. Experimental and commercial diagnostic systems for pulmonary tuberculosis, pneumonia, neoplasms and other diseases have been analyzed.В обзоре рассмотрены возможности применения искусственного интеллекта для интерпретации рентгенограмм органов грудной клетки путем анализа 45 литературных источников. Проанализированы экспериментальные и коммерческие системы диагностики туберкулеза легких, пневмоний, новообразований и других заболеваний

Difficulties associated with differential diagnosis between brain metastases and foci of necrosis resulted from stereotactic radiotherapy (case report and literature review)

Modern advances in oncology can achieve significantly better results in terms of life expectancy in patients with metastatic brain disease. The combination of surgery, systemic therapy, whole brain irradiation and local methods of radiation therapy lead to good indicators for controlling the manifestations of the disease in the brain. Of course, intensification of treatment increases the risk of iatrogenic complications. The use of aggressive stereotactic radiotherapy regimens leads not only to high local control of irradiated metastases, but also to the risk of so-called radiation necrosis. The use of the most up-to-date diagnostic methods does not always allow one to unequivocally differentiate radiation necrosis from continued metastasis growth. The above example shows the need for a careful assessment of such situations and a multidisciplinary approach to interpreting the results of stereotactic radiotherapy