The limits of volume reflection in bent crystals

We show that theory predictions for volume reflection in bent crystals agree with recent experimental data. This makes possible to predict volume reflection angle and efficiency in a broad range of energy for various crystals. A simple formula is proposed for volume reflection efficiency. We derive the physical limits for application of crystal reflection at high-energy accelerators where it may help beam collimation.Comment: 6 pages, 2 figure

Group expansions for impurities in superconductors

A new method is proposed for practical calculation of the effective interaction between impurity scatterers in superconductors, based on algebraic properties of related Nambu matrices for Green functions. In particular, we show that the density of states within the s-wave gap can have a non-zero contribution (impossible either in Born and in T-matrix approximation) from non-magnetic impurities with concentration $c \ll 1$, beginning from $\sim c^{3}$ order.Comment: 5 pages, 1 figur

Improved theoretical prediction for the 2s hyperfine interval in helium ion

We consider the uncertainty of theoretical calculations for a specific difference of the hyperfine intervals in the 1s and 2s states in a light hydrogen-like atom. For a number of crucial radiative corrections the result for hydrogen atom and helium ion appears as an extrapolation of the numerical data from medium to low Z. An approach to a plausible estimation of the uncertainty is suggested using the example of the difference $D_{21}= 8E_{hfs}(2s)-E_{hfs}(1s)$

Подвывих и вывих бедра у детей с последствиями спинномозговых грыж (обзор литературы)

Subluxation or dislocation of the hip joint develops in 30-50% children with spina bifida during the first 2-3 years of life. These problems results from force disbalance between muscle group and other structural changes of the hip and pelvis components of the joint. The goal of treatment subluxation and dislocation of the hip joint in children with spina bifida is to make comfortable daily functions, eliminate the pain, provide the mobility and social independent. Management of subluxation and dislocation in children with spina bifida had changed in the last years because of the analysis long-term results. Indications for surgical treatment were determined more clearly, what made the results of treatment better.У 30-50% детей с последствиями спинномозговых грыж развивается подвывих или вывих в тазобедренном суставе в течение первых 2-3 лет жизни. Эти проблемы являются результатом дисбаланса сил между мышечными группами и другими ассоциированными структуральными изменениями бедренного и тазового компонентов сустава. Целью лечения подвывиха и вывиха бедра у пациентов с последствиями спинномозговой грыжи являются создание им удобства осуществления функций, ликвидация болевого синдрома, обеспечение мобильности и социальной независимости. Тактика лечения подвывиха и вывиха бедра у таких детей значительно изменилась в последние годы в связи проведенным анализом отдаленных результатов. Показания к оперативному лечению были определены более четко, что улучшило результаты

69. Variants of preoperative thermoradiotherapy in locally advanced breast cancer patients

To improve treatment results of locally advanced breast cancer 60 patients with T3-4N1-2M0 TNM stage were undergone complex treatment at the Dept. of Radiotherapy of the CRC. The treatment complex included: radio- or thermoradiotherapy and polychemiohormone-therapy. All patients were subdivided into 3 groups. The first group of 20 patients received radiotherapy only, the second one (18 patients) – thermoradiotherapy, and the third group of 22 patients – thermoradoitherapy plus additional local irradiation of the primary and/or big lymphnode metastases. Radiotherapy was with 2 Gy fractions 5 times per week to the primary tumor and lymphcollectors. Total dose was 40–50 Gy. Results of the therapy were evaluated after 3–4 weeks and the patients were received a surgery. The second group of the patients received local hypertherima after 2 weeks of conventional treatment. Primary tumor and big metastatic nodes were heated. Hyperthermia was performed 2 times per week, with duration of 60 minutes, 3 hours after irradiation. Temperature in tumor was 43–45 C. In the third group of patients additional boost to tumor and/or big metastatic nodes was performed with 2 Gy fractions. Total doses were the same as in first and second group, local tumor dose was 64–72 Gy. Complete or partial regression was more frequently registered in first and second group (39%, 62% respectively). In first group rate was 2%. Rate of postirradiation pathomorphosis of 3–4 grade was 35% in first group, 50% in second, 66% in third group. This data shows improvement of nearest treatment results

Experimental Study of Coherent Summation of Radiation from Two Widely Aperture Pulsed

Emission of two high-power pulsed CO2-lasers with a transverse discharge at atmospheric pressure in the active medium and the output beam aperture 100х100 mm, united by a joint unstable telescopic reso-nator, was coherently summarized under conditions of real ground-level trackon the screen surface, which was remote from output mirror of the laser at a distance of 263 m. Output Brewster windows of laser cu-vettes were manufactured from single-crystal plates of sodium chloride which had a diameter of 300 mm. Mirrors for resonator and optical circuit were manufactured from oxygen-free copper. Active medium - a mixture of gases: CO2: N2: He in the ratio 1 : 2 : 3. Laser pulse duration is 5 microseconds. During the ex-periment, when summing on the screen 2-laser beams at the lowest possible convergence angle of rays, the interference pattern was registered. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3610