Epidemiological and clinical features of lymphoproliferative diseases in the head and neck region

Background. Lymphomas are a heterogeneous group of the lymphoid and hematopoietic system tumors. Neoplastic process often develops in head and neck area, including the integumentary tissues, orbit, nasal cavity, paranasal sinuses, oral cavity, pharynx, salivary glands, thyroid gland, as well as neck lymph nodes. The difficulties of head and neck lymphomas diagnosis are significant, since very often there is a combined non-tumor pathology. The high heterogeneity of lymphomas in the head and neck area requires structuring knowledge about their epidemiology and clinical manifestations.Objective: to study the epidemiological and clinical features of the head and neck lymphoproliferative diseases, which will lead to an improvement in diagnostic quality of this nosology's.Materials and methods. The frequency of head and neck lymphoproliferative diseases detection was estimated based on the study of epicrisis and clinical data of 174 patients hospitalized at the N.N. Blokhin National Medical Research Center of Oncology in the period from 2000 to 2020.Results. Taking into account the modern clinical and morphological classification of lymphomas of the World Health Organization (2017), information about the features of localization, characteristic signs of extranodal foci and lymph nodes is presented. Detection frequency of various subtypes non-Hodgkin's and Hodgkin's lymphomas were determined on a sufficient cohort of patients.Conclusion. Based on the analysis of clinical and morphological features of head and neck lymphomas, epidemiological and clinical features are described in detail, and differences in the symptoms and clinical manifestations of non-Hodgkin's and Hodgkin's lymphomas with a predominant head and neck involvement are revealed

Комп'ютерне моделювання адсорбції фулерену на графені

У роботі адсорбція фулерену C60 на поверхні та краях бездефектного графена вивчалася за допомогою комп'ютерного моделювання в рамках класичної молекулярної динаміки. Комп'ютерна модель одиночного бездефектного фулерену C60 побудована методом мінімізації енергії з використанням потенціалу Бреннера другого покоління (REBO), і визначена енергія зв'язку кожного атома вуглецю у фулерені. Для розгляду адсорбції фулерену на поверхні графена тим самим методом отримано комп'ютерну модель "нескінченного" бездефектного графена з урахуванням періодичних умов для граничних атомів. Для розгляду адсорбції фулерену на графенових краях побудовано комп'ютерну модель бездефектного нанографена. Встановлено, що адсорбція фулерену C60 на поверхні графена може бути реалізована різними способами. Отримано геометричні характеристики фулерену C60, адсорбованого на поверхні графена. Встановлено, що фулерен краще адсорбується на краю нанографена типу "крісла з ручками" і гірше на "кутових" атомах нанографена. Енергія зв'язку для адсорбції на краю нанографена може бути майже вдвічі більшою, ніж найвища енергія зв'язку адсорбції на поверхні графена, і спостерігається сильніша деформація форми фулерену.In the present work, the adsorption of fullerene C60 onto the surface and edges of defect-free graphene was studied by computer simulation within the framework of classical molecular dynamics. The computer model of single defect-free fullerene C60 was built by the energy minimization method using the secondgeneration Brenner potential (REBO), and the cohesive energy of each carbon atom in fullerene was determined. For consideration of fullerene adsorption on the graphene surface, a computer model of "infinite" defect-free graphene was obtained by the same method with a glance of periodic conditions for boundary atoms. For fullerene adsorption on graphene edges to be considered, a computer model of defect-free nanographene was constructed. It was obtained that fullerene C60 adsorption on the graphene surface can be realized by different ways. The geometrical characteristics of fullerene C60 adsorbed on the graphene surface were obtained. It was established that fullerene is better adsorbed on the armchair edge of nano-graphene and worse on the "corner" atom of nano-graphene. The binding energy for adsorption on the nano-graphene edge can be almost twice as large as the highest binding energy of adsorption on the graphene surface, and stronger deformation of the fullerene shape is observed

Surface morphology, magnetic resonant and antistatic properties of 07S11-KVfabric coated with stainless steel

A study of the mixed 07С11-KВ fabric (produced by Mogotex) with a coating of steel 12X18H10T, obtained by the method of pulsed cathode arc deposition in a vacuum of 3.5×10–3 Pa, was conducted. It is shown that optical microscopy has a number of advantages in studying the surface morphology of such objects as compared to scanning electron microscopy. The most contrast image is formed using dark-field illumination. When coating is applied, a droplet phase is formed, the droplet sizes vary from 2 to 10 microns. By the method of electron paramagnetic resonance, it has been established that the spectrum of coated fabric has an asymmetrical spectral line with a width of 101 mT, which indicates a high concentration of magnetic resonance centers and a significant resonant absorption of microwave energy. Resonant absorption at low magnetic fields is determined by clusters of iron, nickel, chromium, titanium, etc., with weak nonresonant absorption. The specific surface resistance of the fabric (side 1 / side 2) is 3.3×105 ohm and 5.6×105 ohm, respectively