Projectile fragmentation at Fermi energies with transport simulations

Projectile fragmentation at Fermi energies is an important method to produce radioactive beams for the study of isospin asymmetric nuclear matter. Fragmentation is usually parametrized successfully by empirical phase space models. In this contribution we apply a microscopical method, semiclassical transport theory, to study in detail the reaction mechanism of the fragmentation process. We apply it to experimental data of 18O on 181Ta at E/A = 35 MeV measured in Dubna. We calculate consistently the excitation energy of the primary fragments and take into account their decay by a statistical model. It is found that the dissipative part of the fragment spectra is well described by transport theory. However, there are in addition important direct and collective contributions

Low temperature breakdown of coherent tunneling in amorphous solids induced by the nuclear quadrupole interaction

We consider the effect of the internal nuclear quadrupole interaction on quantum tunneling in complex multi-atomic two-level systems. Two distinct regimes of strong and weak interactions are found. The regimes depend on the relationship between a characteristic energy of the nuclear quadrupole interaction $\lambda_{\ast}$ and a bare tunneling coupling strength $\Delta_{0}$. When $\Delta_{0}>\lambda_{\ast}$, the internal interaction is negligible and tunneling remains coherent determined by $\Delta_{0}$. When $\Delta_{0}<\lambda_{\ast}$, coherent tunneling breaks down and an effective tunneling amplitude decreases by an exponentially small overlap factor $\eta^{\ast}\ll1$ between internal ground states of left and right wells of a tunneling system. This affects thermal and kinetic properties of tunneling systems at low temperatures $T<\lambda_{*}$. The theory is applied for interpreting the anomalous behavior of the resonant dielectric susceptibility in amorphous solids at low temperatures $T\leq 5$mK where the nuclear quadrupole interaction breaks down coherent tunneling. We suggest the experiments with external magnetic fields to test our predictions and to clarify the internal structure of tunneling systems in amorphous solids.Comment: To appear in the Physical Review

The Use of the Raabe Aspirator in Intraoperative neurophysiological Monitoring during Decompression and Stabilization Interventions for Degenerative Diseases and Injuries of the Lumbar Spine

Background. Raabe probe is a suction device with monopolar motor fibers mapping capabilities. A number of technical characteristics make it possible to use it for intraoperative neurophysiological monitoring during posterior lumbar fusion surgery.The aim of this study was to analyze our experience of Raabe probe using for intraoperative neurophysiological monitoring during posterior lumbar fusion surgery.Methods. Ninety-eight patients (55 women and 43 men) with degenerative changes and injuries of the lumbar spine were included into the study, mean age – 56.3 ± 12.8 years. Patients underwent the following operations: 85 cases (86.7 %) – spinal roots decompression with fusion by dorsal and ventral implants, 12 cases (12.2 %) – decompression with only dorsal fusion, 1 case (1.0 %) – dorsal fusion without decompression. In all cases intraoperative neurophysiological monitoring control by B. Calancie method with Raabe probe using was performed.Results. With a critical current threshold of 12 mA, the sensitivity of the method is 94 %, the specificity is 97 %. Comparing the thresholds of the M-response at the stage of screw stimulation, no statistically significant differences were found between the groups of true-positive and false-positive results, both for interested (p = 0.09) and intact (p = 0,16) screws. At the stage of the impactor stimulation, the threshold of the M-response in the true-positive group made11.39 ± 7.97 mA, and in the false-positive group – 24.16 ± 8.85 mA (p &lt; 0.05).Conclusion. Raabe probe application for intraoperative neurophysiological monitoring during posterior lumbar fusion surgery show the high sensitivity and specificity. The most reliable sign of pedicle wall breach is a threshold below than 12 mA at the stage of the impactor stimulation

КЛИНИКО-ЭПИДЕМИОЛОГИЧЕСКИЕ ОСОБЕННОСТИ ЭНТЕРОВИРУСНОГО МЕНИНГИТА В ПЕРИОД СЕЗОННОЙ ВСПЫШКИ 2015 ГОДА

The aim. To analyse the morbidity of the enterovirus infection (EI) in Novokuznetsk – the major industrial city of Western Siberia and to determine the clinical peculiarities of enterovirus meningitis (EM) in the outbreak period in 2015.The materials and methods. There have been analysed the official statistical data in the period of 2006–2015 and the enterovirus meningitis, clinical manifestations in 148 patients, hospitalized in 2015. Liquor was tested by the method of the polymerase chain reaction (PCR) for presence RNA of the enteroviruses. The C-reactive protein value was tested by the method of the latex test and the procalcitonin value was tested by the method of the immunoenzymatic analysis. The statistical material treatment has been done using InStat programme.The results. There has been registered 3,2 times growth of the enterovirus infection morbidity in 2015, compared to 2014, which 6,2 times exceeds Russia, s average rate. The enteroviruses ECHO 30 have been identified in patients, biological material and in wastewater. In the structure of the clinical forms the share of the enterovirus meningitis makes 92, 91%. The children, s morbidity 4,57 times exceeds the total burden of disease. The age structure accompanying the enterovirus meningitis: children 2–6 years of age – 47,3%, 7–14 years of age – 27,7%, 15–17 years of age – 7,43%, 18–53 years of age – 17,57%. Vomiting and headache in children (under the age of 7) are registered rarely, and the full meningeal syndrome and the neutrophil pleocytosis in liquor in children (under the age of 7) are registered more frequently. The rate of children and adults has increased in 2015, compared to 2005. The alteration in clinical picture relates to degree of meningeal syndrome intensity and catarrhal manifestations. The C-reactive protein value (in 67,21%) and the procalcitonin value (in 100%) don, t exceed the threshold values in patients with leucocytosis and pleocytosis of liquor with neutrophil/mixed character, which enables to differentiate enterovirus meningitis from bacterial meningitis and to exclude antibiotic treatment.The conclusion. The dynamics of the rate of the enterovirus infection morbidity on the territory under investigation differs from Russia, s average rate. The enterovirus meningitis has got clinical and age peculiarities in different epidemic seasons.Цель. Провести анализ заболеваемости энтеровирусной инфекцией (ЭВИ) в крупном промышленном городе Западной Сибири – Новокузнецке и установить клинические особенности энтеровирусного менингита (ЭВМ) в период вспышки 2015 г. Материалы и методы. Изучены данные официальной статистики за 2006–2015 гг. и клинические проявления ЭВМ у 148 больных, госпитализированных в 2015 г. Исследовали ликвор методом ПЦР на наличие РНК энтеровирусов. Определяли уровень С-реактивного белка (СРБ) методом латекс-теста и прокальцитонина (ПКТ) методом ИФА. Статистическую обработку материала проводили с помощью программы InStat.Результаты. В 2015 г. зарегистрирован подъем заболеваемости ЭВИ в 3,2 раза по сравнению с 2014 г., в 6,2 раза выше среднего по РФ. В биологическом материале от больных и в сточных водах идентифицированы энтеровирусы ECНO 30. В структуре клинических форм доля ЭВМ составила 92,91%. Заболеваемость детей в 4,57 раза превысила совокупный показатель. Возрастная структура при ЭВМ: дети 2–6 лет 47,3%, 7–14 лет – 27,7%, 15–17 лет – 7,43%, 18–53 года – 17,57%. У детей до 7 лет реже регистрировались рвота и головная боль, чаще развивались полный менингеальный синдром и нейтрофильный плеоцитоз в ликворе. В 2015 г. по сравнению с 2005 г. увеличился удельный вес детей до 7 лет и взрослых. Изменение клинической картины касалось полноты выраженности менингеального синдрома и катаральных проявлений. У пациентов с лейкоцитозом крови и нейтрофильным/смешанным характером плеоцитоза ликвора не превышали пороговых значений содержания СРБ в 67,21%, ПКТ – в 100%, что позволяло дифференцировать ЭВМ с бактериальным менингитом и исключить применение антибиотиков.Заключение. Динамика показателя заболеваемости ЭВИ на изучаемой территории отличается от среднего по России. ЭВМ имеет возрастные и клинические особенности в разные эпидемические сезоны

Предикторы эффективности интраоперационной лучевой терапии в органосохраняющем лечении раннего рака молочной железы

Background. Despite the improvement in combined modality treatment of early breast cancer (BC), the rate of locoregional recurrence remains in the range of 7-15 %. Therefore, the search for prognostic factors for BC is of great significance. The aim of the study was to estimate the relationship between clinical and morphological parameters and 10-year recurrence-free survival rate in BC patients after combined modality treatment including intraoperative radiotherapy (IOLT). Material and Methods. The study enrolled 383 patients with morphologically verified T1-3N0-1M0 stage breast cancer. The median age of the patients was 53 years (range: 28 to 80 years). All patients underwent breast-conserving surgery with IOLT delivered to the tumor bed at a single dose of 10 Gy (24.8 Gy according to the iso-effect). External beam radiation therapy (EBRT) to the conserved breast was given in the postoperative period. Results. Within the 10-year follow-up, 20 (5.2 %) locoregional recurrences occurred, of which 7 (35 %) developed with a primary tumor size of ≤ 2 cm (T1), and most recurrences - 13 (65 %) were detected with the primary tumor size corresponding to T2-3. In patients with luminal A subtype of BC and in patients with triple negative BC, the recurrence rates were 5 % and 45 %, respectively. The 10-year survival rate of patients after combined modality treatment with IOLT was 94.8 %. Conclusion. The results obtained indicate the relationship between the recurrence rate and clinical/ morphological parameters of the tumor, such as tumor size and molecular subtype. These parameters should be taken into account when planning treatment in patients with early BC.Введение. Несмотря на совершенствование методов комбинированного лечения раннего рака молочной железы (РМЖ), частота локорегионарных рецидивов остается на уровне 7-15 %. В связи с этим поиск прогностических факторов течения заболевания остается актуальной задачей. Цель исследования -оценка взаимосвязи клинико-морфологических параметров с показателями 10-летней безрецидивной выживаемости больных РМЖ, перенесших комбинированное лечение с интраоперационной лучевой терапией (ИОЛТ). Материал и методы. В исследование включено 383 больных с морфологически верифицированным РМЖ стадий T1-3N0-1M0. Средний возраст пациенток 53 года (28-80 лет). В плане комбинированного лечения всем пациенткам выполнялись органосохраняющие операции с ИОЛТ на ложе удаленной опухоли в однократной дозе 10 Гр (24,8 Гр по изоэффекту). В послеоперационном периоде осуществлялась дистанционная гамма-терапия (ДГТ) на оставшуюся часть молочной железы. Результаты. За 10-летний период наблюдения отмечено 20 (5,2 %) локорегионарных рецидивов, из них 7 (35 %) развилось при первичной опухоли размером ≤2 см (Т1), а большинство рецидивов - 13 (65 %) - диагностировано при исходной распространенности опухоли, соответствующей Т2-3. Частота рецидивов у больных с люминальным А подтипом опухоли - 5 %, у пациенток с трижды негативным подтипом опухоли - 45 %. Безрецидивная 10-летняя выживаемость больных после комбинированного лечения с ИОЛТ составила 94,8 %. Заключение. Полученные результаты свидетельствуют о наличии взаимосвязи между частотой рецидивов и такими клинико-морфологическими параметрами опухоли, как размер и молекулярный подтип опухоли, которые должны учитываться при планировании лечения у больных ранними формами РМЖ

Estimation of quality of hot pressed briquettes as a type of metallurgical charge materials

The basic principles of construction are formulated in the work and a description of the technological process of hot briquetting of ferrous metal waste as a way of converting fine metal particles into a dimensional semi-finished product of a given size and chemical composition is given. The description of equipment for the implementation of this process with highly efficient non-oxidizing heating and complete safe neutralization of flue gases is given. The results of melting of hot-pressed briquettes in various melting units are presented. It is shown that briquettes cleaned from coolant with a density of 6500–7100 kg/m3 are full-fledged substitutes for bulk scrap. Recommendations and a feasibility study on the feasibility of introducing the hot briquetting process into production at the enterprises of the bearing, machine-building and metallurgical industries, followed by the use of hotpressed briquettes to produce cast billets for their own purposes, are given