404 research outputs found
General solution of equations of motion for a classical particle in 9-dimensional Finslerian space
A Lagrangian description of a classical particle in a 9-dimensional flat
Finslerian space with a cubic metric function is constructed. The general
solution of equations of motion for such a particle is obtained. The Galilean
law of inertia for the Finslerian space is confirmed.Comment: 10 pages, LaTeX-2e, no figures; added 2 reference
Computation of the minimum eigenvalue for a nonlinear Sturm-Liouville problem
© 2014, Pleiades Publishing, Ltd. A condition for the existence of a minimum eigenvalue corresponding to a positive eigenfunction of the nonlinear eigenvalue problem for an ordinary differential equation is determined. The problem is approximated by a mesh scheme of the finite element method. The convergence of approximate solutions to exact ones is studied. Theoretical results are illustrated by numerical experiments for a model problem
Spectral Properties of Single Crystals of Synthetic Diamond
The half-width of the spectrum of Raman scattering (RS) of the first order of a diamond single crystal grown in a nickel-free system containing nitrogen getters is identical to all growth sectors (1.69 ±
0.02 cm−1). The sectorial inhomogeneity is not reflected in the transmission spectra and birefringence of this crystal. The nitrogen concentration is 4⋅1017 cm−3. For different growth sectors of the diamond crystal grown in the Ni–Fe–C system, the half-width of the Raman line varies from 1.74 to 2.08 cm−1,
differences in the transmission spectra and birefringence are observed, and photoluminescence is revealed. The concentration of nitrogen in the growth sectors {001} is 1.6⋅1019 cm−3, the content of nickel is estimated to be at a level of 1019 cm−3, and the content of nitrogen in the {111} sectors is 4⋅1019 cm−3
On the mechanisms of superfluidity in atomic nuclei
A system of equations is obtained for the Cooper gap in nuclei. The system
takes two mechanisms of superfluidity into account in an approximation
quadratic in the phonon- production amplitude : a Bardeen- Cooper- Schrieffer
(BCS) type mechanism and a quasiparticle- phonon mechanism. These equations are
solved for 120 Sn in a realistic approximation. If the simple procedures
proposed are used to determine the new particle- particle interaction and to
estimate the average effect, then the contribution of the quasiparticle- phonon
mechanism to the observed width of the pairing gap is 26% and the BCS-type
contribution is 74%. This means that at least in semimagic nuclei pairing is of
a mixed nature - it is due to the two indicated mechanisms, the first being
mainly a surface mechanism and the second mainly a volume mechanism.Comment: 6 page
Dynamics of quantum systems
A relation between the eigenvalues of an effective Hamilton operator and the
poles of the matrix is derived which holds for isolated as well as for
overlapping resonance states. The system may be a many-particle quantum system
with two-body forces between the constituents or it may be a quantum billiard
without any two-body forces. Avoided crossings of discrete states as well as of
resonance states are traced back to the existence of branch points in the
complex plane. Under certain conditions, these branch points appear as double
poles of the matrix. They influence the dynamics of open as well as of
closed quantum systems. The dynamics of the two-level system is studied in
detail analytically as well as numerically.Comment: 21 pages 7 figure
Characteristics of Phenotypic and Genetic Properties of <i>Francisella tularensis</i> 15 NIIEG Vaccine Strain with an Extended Storage Period
Investigated have been cultural-morphological, biochemical and genetic properties of lyophilized cultures of F. tularensis 15 NIIEG vaccine strain, accumulated within 60-years term and deposited at the State Collection of Pathogenic Microorganisms of Scientific Center on Expertise of Medical Application Products. The studies undertaken have demonstrated that storing of the strains in such a form at low temperatures, does not prevent changes of their genetic and phenotypic properties to the full extent. It is established that F. tularensis 15 NIIEG strain lyophilized in 1953, 1966, 1969, 2003 and 2012 maintains its immunogenic properties when cultivated on nutrient media Ft-agar with or without addition of blood, based on dissociation rates (87-99 %) of SR-colonies. While F. tularensis 15 NIIEG strain 1990 contains specified amounts (not less than 80 %) of immunogenic colonies if cultivated on nutrient media with the addition of blood, and fails to meet the requirements - if cultivated without. Identified in F. tularensis 15 NIIEG strain 1987 SR-colony decrement of 70-75 % in case of cultivation with or without addition of blood testifies to the deterioration of its immunogenic properties. RAPD and ERIC typing has showed high stability of the genome of F. tularensis 15 NIIEG cultures lyophilized at different times. Tularemia microbe vaccine strain has unique RAPD and ERIC profiles, insignificant alteration of which is observed upon storage of pathogen subculture in the dried from
Hadronic Regge Trajectories: Problems and Approaches
We scrutinized hadronic Regge trajectories in a framework of two different
models --- string and potential. Our results are compared with broad spectrum
of existing theoretical quark models and all experimental data from PDG98. It
was recognized that Regge trajectories for mesons and baryons are not straight
and parallel lines in general in the current resonance region both
experimentally and theoretically, but very often have appreciable curvature,
which is flavor-dependent. For a set of baryon Regge trajectories this fact is
well described in the considered potential model. The standard string models
predict linear trajectories at high angular momenta J with some form of
nonlinearity at low J.Comment: 15 pages, 9 figures, LaTe
Quantum-mechanical and semiclassical study of the collinear three-body Coulomb problem: Inelastic collisions below the three-body disintegration threshold
Анализ гистологического строения, типов роста и характера метастазирования осложненного колоректального рака
Objective: to assess the parameters characterizing a relationship between the histological and growth patterns and grade of a malignant tumor, the nature of regional and distant metastases, patient gender and age, and the type of urgent complications in colorectal cancer.Subjects and methods. Information on 1098 patients with urgent colonic cancer types treated in Smolensk and its region in the period 2001 to 2013 was studied. This information was given from the records of the Clinical Emergency Medical Care Hospital, City Clinical Hospital One, the Smolensk Regional Clinical Hospital, Smolensk Regional Oncology Clinical Dispensary, and the central district hospitals of the Smolensk Region. Morphological examinations were made at the Smolensk Regional Institute of Pathology.Results. Among the examinees, the proportion of women and men was 54.4% (n = 597) and 45.6 % (n = 501), respectively. The investigation recorded exophytic, endophytic, and mixed tumor growth patterns in 46.5, 52.3, and 1.2 %, respectively. The endophytic cancer growth pattern was most commonly complicated by acute intestinal obstruction, perifocal inflammation, tumor perforation, and concomitant complications. At the same time, the exophytic growth pattern was characterized by enteric bleeding in 89 % of cases. Complications, such as tumor perforation and enteric bleeding, are more commonly attended with tumor ulceration that was usually detected on the left side (in as high as 80.2 % of cases). A malignant tumor was most frequently recorded to grow into the retroperitoneal fat, small bowel, mesentery, and other colonic segments (15.0, 15.3, and 14.5 %, respectively). The most common complications in moderate-grade adenocarcinoma were enteric bleeding and tumor perforation (80.8 and 76.5 %, respectively; p < 0.05). Regional colorectal cancer metastases were generally usually recorded in patients aged less than 60 years (64 %). Higher distant metastasis rates were noted in those aged over 80 years (44.7 %).Conclusion. Colon cancer is most commonly complicated by ileus, perforation, and concomitant complications and mainly characterized by the left-sided location, obvious local extent, and poor survival prognosis of the endophytic growth pattern, ulceration, moderate and highgrade of cancer.Цель исследования – оценить параметры, характеризующие зависимость между гистологическим строением злокачественной опухоли, типом роста, степенью дифференцировки новообразования, характером регионарного и отдаленного метастазирования, полом и возрастом больного и видом ургентного осложнения колоректального рака.Материалы и методы. Изучены сведения о 1098 больных с ургентными формами рака толстой кишки, которые в период с 2001 по 2013 г. были пролечены на территории Смоленска и Смоленской области. Данная информация представлена по материалам ОГБУЗ «Клиническая больница скорой медицинской помощи», ОГБУЗ «Городская клиническая больница № 1», ОГБУЗ «Смоленская областная клиническая больница», ОГБУЗ «Смоленский областной онкологический клинический диспансер», а также централь- ных районных больниц Смоленской области. Морфологические исследования проводили на базе ОГБУЗ «Смоленский областной институт патологии».Результаты. Среди обследованных пациентов доля женщин составила 54,4 % (n = 597), мужчин – 45,6 % (n = 501). По данным проведенного исследования, экзофитный рост новообразования зарегистрирован в 46,5 % наблюдений, эндофитный – в 52,3 %, смешанный – в 1,2 %. Наиболее часто эндофитный рост образования сопровождался острой кишечной непроходимостью, перифокальным воспалением, перфорацией опухоли и наличием сочетанных осложнений. В то же время экзофитный тип роста характеризовался кишечным кровотечением в 89 % случаев. Такие осложнения, как перфорация опухоли и кишечное кровотечение, чаще сопровождались изъязвлением опухоли, которое обычно выявляли при левосторонней локализации (до 80,2 %). Наиболее часто регистрировали прорастание злокачественного новообразования в забрюшинную клетчатку, тонкую кишку, брыжейку и другие отделы толстой кишки (15,0; 15,3 и 14,5 % соответственно). При умеренно-дифференцированной аденокарциноме наиболее частыми осложнениями были кишечное кровотечение и перфорация опухоли (80,8 и 76,5 % соответственно; p < 0,05). Регионарные метастазы колоректального рака обычно регистрировали у пациентов в возрасте до 60 лет (64 %). Более высокую частоту отдаленного метастазирования отмечали у больных старше 80 лет (44,7 %).Выводы. Рак толстой кишки наиболее часто сопровождается кишечной непроходимостью, перфорацией и сочетанными осложнениями и характеризуется преимущественно левосторонней локализацией, выраженным местным распространением, неблагоприятным в плане прогноза выживаемости эндофитным ростом, изъязвлением, средней и низкой степенью дифференцировки злокачественного новообразования
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