Global Spiral Modes in NGC 1566: Observations and Theory

We present an observational and theoretical study of the spiral structure in galaxy NGC 1566. A digitized image of NGC 1566 in I-band was used for measurements of the radial dependence of amplitude variations in the spiral arms. We use the known velocity dispersion in the disk of NGC 1566, together with its rotation curve, to construct linear and 2D nonlinear simulations which are then compared with observations. A two-armed spiral is the most unstable linear global mode in the disk of NGC 1566. The nonlinear simulations are in agreement with the results of the linear modal analysis, and the theoretical surface amplitude and the velocity residual variations across the spiral arms are in qualitative agreement with the observations. The spiral arms found in the linear and nonlinear simulations are considerably shorter than those observed in the disk of NGC 1566. We argue therefore, that the surface density distribution in the disk of the galaxy NGC 1566 was different in the past, when spiral structure in NGC 1566 was linearly growing.Comment: 41 pages, 20 figures, to be published in the Astrophysical Journa

Dynamics of Gaseous Disks in a Non-axisymmetric Dark Halo

The dynamics of a galactic disk in a non-axisymmetric (triaxial) dark halo is studied in detail using high-resolution, numerical, hydrodynamical models. A long-lived, two-armed spiral pattern is generated for a wide range of parameters. The spiral structure is global, and the number of turns can be two or three, depending on the model parameters. The morphology and kinematics of the spiral pattern are studied as functions of the halo and disk parameters. The spiral structure rotates slowly, and its angular velocity varies quasi-periodically. Models with differing relative halo masses, halo semi-axis ratios, distributions of matter in the disk, Mach numbers in the gaseous component, and angular rotational velocities of their halos are considered.Comment: 22 pages, 11 figure

Опыт вакцинопрофилактики пневмококковой инфекции у взрослых на примере Красноярского края

The aim of the study was to investigate efficacy of specific prevention of pneumococcal infection in high-risk group patients living at Krasnoyarsk krai. Methods. The study involved 12,080 patients with a high risk of pneumococcal infection including patients with chronic lung diseases, chronic heart failure (CHF) and diabetes mellitus. A special questionnaire was developed which included medical history for the previous 1 year and for 1 year after the vaccination. Results. CHF was diagnosed in 41.08% of patients, diabetes was diagnosed in 28.44%, chronic lung diseases were diagnosed in 30.07%; 2.4% of patients had pneumonia. PCV13 vaccine (Prevenar 13) was used in 9,986 patients (82.67%) including 5,070 patients (41.97%) vaccinated against flu and pneumococcus simultaneously. PPV23 (Pneumo-23) vaccine was used in 1,967 patients (16.28%) including 1,181 patients (9.83%) vaccinated against flu and pneumococcus simultaneously. Due to the broad-scale vaccination against pneumococcal infection, exacerbation rate reduced trice, number of hospitalisations related to exacerbations reduced by 11.5 times, morbidity of pneumonia reduced by 4.8 times, morbidity of acute respiratory infections and flu reduced by 6.6 times. Conclusion. The results confirmed high efficacy and safety of 13-valent conjugate pneumococcal vaccine and 23-valent polysaccharide pneumococcal vaccine. The vaccination allowed reducing morbidity of respiratory infection and decrease number of hospitalisations due to exacerbations of chronic diseases.Целью исследования явилось изучение эффективности специфической профилактики пневмококковой инфекции у лиц групп риска, проживающих в Красноярском крае. Материалы и методы. Обследованы лица (n = 12 080) групп риска – с хроническими заболеваниями легких (ХЗЛ), хронической сердечной недостаточностью (ХСН) и сахарным диабетом (СД). Для оценки клинической эффективности вакцинации разработана специальная анкета, включающая оценку анамнеза в течение 1 года, предшествующего вакцинации, и анамнез основного заболевания в течение 1 года после вакцинации. Результаты. Продемонстрирована эффективность и безопасность применения Превенар-13 – 13-валентной пневмококковой конъюгированной и Пневмо-23 – 23-валентной пневмококковой полисахаридной вакцин. Проанализирован опыт иммунизации лиц с высоким риском развития пневмококковой инфекции: у 41,08 % установлена ХСН; у 28,44 % – СД; у 30,07 % – ХЗЛ; 2,4 % перенесли пневмонию. Превенар-13 привиты 9 986 (82,67 %) человек, из них в сочетании с противогриппозной вакциной – 5 070 (41,97 %); Пневмо-23 привиты 1 967 (16,28 %) человек, из них в сочетании с противогриппозной вакциной – 1 181 (9,83 %). Благодаря проведению в регионе масштабной кампании по профилактике пневмококковой инфекции получены положительные результаты – число обострений или декомпенсаций основных заболеваний среди привитых сократилось в 3 раза, количество госпитализаций по поводу обострения и декомпенсации основного заболевания – в 11,5 раза, заболеваемость пневмониями – в 4,8 раза, а острыми респираторными заболеваниями или гриппом – в 6,6 раза. Заключение. Полученные результаты свидетельствуют о высокой эффективности вакцинации против пневмококковой инфекции по предупреждению развития пневмоний, снижению заболеваемости респираторными инфекциями, сокращению числа госпитализаций по поводу обострений или декомпенсаций в результате стабилизации течения основного заболевания среди пациентов с ХЗЛ, ХСН и СД

Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

Contains fulltext : 172380.pdf (publisher's version ) (Open Access

Efficiency of estimating duration of a signal with unknown amplitude

Quasi-likelihood and maximum likelihood algorithm for estimating duration of a signal with arbitrary share and unknown amplitude are synthesized. Operation efficiency characteristics for the synthesized algorithms are determined. Operation of the synthesized algorithms is verified and applicability limits for asymptotic expressions are obtained using computer emulation