On the Possibility of the Detection of Extinct Radio Pulsars

We explore the possibilities for detecting pulsars that have ceased to radiate in the radio band. We consider two models: the model with hindered particle escape from the pulsar surface (first suggested by Ruderman and Sutherland 1975) and the model with free particle escape (Arons 1981; Mestel 1999). In the model with hindered particle escape, the number of particles that leave the pulsar magnetosphere is small and their radiation cannot be detected with currently available instruments. At the same time, for the free particle escape model, both the number of particles and the radiation intensity are high enough for such pulsars to be detectable with the presently available receivers such as GLAST and AGILE spacecrafts. It is also possible that extinct radio pulsars can be among the unidentified EGRET sources.Comment: 5 pages, 1 figure corrected version of the paper that was published in Astronomy Letter

Self-consistent solution of Kohn-Sham equations for infinitely extended systems with inhomogeneous electron gas

The density functional approach in the Kohn-Sham approximation is widely used to study properties of many-electron systems. Due to the nonlinearity of the Kohn-Sham equations, the general self-consistence searching method involves iterations with alternate solving of the Poisson and Schr\"{o}dinger equations. One of problems of such an approach is that the charge distribution renewed by means of the Schr\"{o}dinger equation solution does not conform to boundary conditions of Poisson equation for Coulomb potential. The resulting instability or even divergence of iterations manifests itself most appreciably in the case of infinitely extended systems. The published attempts to deal with this problem are reduced in fact to abandoning the original iterative method and replacing it with some approximate calculation scheme, which is usually semi-empirical and does not permit to evaluate the extent of deviation from the exact solution. In this work, we realize the iterative scheme of solving the Kohn-Sham equations for extended systems with inhomogeneous electron gas, which is based on eliminating the long-range character of Coulomb interaction as the cause of tight coupling between charge distribution and boundary conditions. The suggested algorithm is employed to calculate energy spectrum, self-consistent potential, and electrostatic capacitance of the semi-infinite degenerate electron gas bounded by infinitely high barrier, as well as the work function and surface energy of simple metals in the jellium model. The difference between self-consistent Hartree solutions and those taking into account the exchange-correlation interaction is analyzed. The case study of the metal-semiconductor tunnel contact shows this method being applied to an infinitely extended system where the steady-state current can flow.Comment: 38 pages, 9 figures, to be published in ZhETF (J. Exp. Theor. Phys.

КЛИНИЧЕСКАЯ ЭФФЕКТИВНОСТЬ ВЫСОКОДОЗНОЙ ИММУНОСУПРЕССИВНОЙ ТЕРАПИИ С ТРАНСПЛАНТАЦИЕЙ КРОВЕТВОРНЫХ СТВОЛОВЫХ КЛЕТОК ПРИ РАССЕЯННОМ СКЛЕРОЗЕ

Multiple sclerosis (MS) is a major infl ammatory and demyelinating disease of the central nervous system (CNS), associated with a broad spectrum of physical, psychological, and social impairments. High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic stem cell transplantation (AHSCT) is a new and promising approach to MS treatment. In this paper we present the clinical monitoring results of 93 patients with different MS types after AHSCT. The mobilization and transplantation procedures were well tolerated. At long-termfollow-up (mean 47,2 months), the overall clinical response in terms of disease improvement or stabilization was 95% in patients with relapsing-remitting MS and 77,5% in patients with progressive MS. The results of our study support the feasibility of AHSCT in MS patients.Рассеянный склероз (РС) – хроническое прогрессирующее заболевание центральной нервной системы (ЦНС), которое сопровождается не только физическими нарушениями, но и отклонениями в психоэмоциональной, духовной и социальной сферах. Высокодозная иммуносупрессивная терапия с трансплантацией кроветворных стволовых клеток (ВИСТ + ТКСК) – новый эффективный метод лечения РС. В данной публикации представлены результаты оценки клинической эффективности у больных с прогрессирующим (ПРС) и ремиттирующим вариантами РС (РРС) в разные сроки после ВИСТ + ТКСК. В исследование включено 93 пациента в возрасте от 18 до 50 лет с верифицированным диагнозом РС. Медиана длительности наблюдения составила 47,2 мес. Для оценки клинической эффективности использовались индекс EDSS и данные МРТ. Проведенный анализ переносимости и побочных эффектов ВИСТ + ТКСК показал, что процедура трансплантации хорошо переносилась больными. Не было отмечено летальных исходов и тяжелых осложнений в посттрансплантационном периоде. Суммарно положительный эффект ВИСТ + ТКСК (стабилизация и улучшение) в отдаленные сроки после трансплантации достигнут у 95% больных с РРС и у 77,5% – с ПРС. Таким образом, результаты исследования доказывают высокую эффективность ВИСТ + ТКСК при РС

CLINICAL EFFECTIVENESS OF HIGH-DOSE IMMUNOSUPPRESSIVE THERAPY WITH AUTOLOGOUS HEMATOPOIETIC STEM CELL TRANSPLANTATION IN MULTIPLE SCLEROSIS PATIENTS

Multiple sclerosis (MS) is a major infl ammatory and demyelinating disease of the central nervous system (CNS), associated with a broad spectrum of physical, psychological, and social impairments. High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic stem cell transplantation (AHSCT) is a new and promising approach to MS treatment. In this paper we present the clinical monitoring results of 93 patients with different MS types after AHSCT. The mobilization and transplantation procedures were well tolerated. At long-termfollow-up (mean 47,2 months), the overall clinical response in terms of disease improvement or stabilization was 95% in patients with relapsing-remitting MS and 77,5% in patients with progressive MS. The results of our study support the feasibility of AHSCT in MS patients

COMPARATIVE EFFICIENCY AND TOLERABILITY OF CURRENT THERAPIES FOR EARLY RHEUMATOID ARTHRITIS

Objective: to compare the efficiency and safety of four treatment regimens using methotrexate (MT),  leflunomide (LEF),  and a combination  of MT and glucocorticoids  (GC)  for early rheumatoid  arthritis (RA) (disease duration <2 years).Subjects and methods. 141 patients with early RA (of them there were 122 women; mean age 51 years; mean disease duration  7.8 months;  mean DAS28 6.0) were randomized  to 4 treatment groups: 1) MT 10–20 mg/week (n = 35); 2) MT 10–20 mg/week + oral GC equivalent to 10 mg/day of prednisolone  (n = 34); 3) MT 10–20 mg/week + oral CG + single intravenous administration of methylprednisolone (MP) 1000 mg at baseline (n = 35); 4) LEF 20 mg/day (n = 37). The patients were matched for main clinical and demographic  characteristics. The duration of treatment was 1 year. Its efficiency was evaluated according to the European  League Against Rheumatism (EULAR)  criteria.Results. 125 patients completed one-year treatment. At this time, 11.4% of the patients achieved remission (DAS28 <2.6) in the MT group, 37.5% in the MT+GC group, 29.4% in the MT+GC+MP group, and 16.2% in the LEF group. Adverse events, mainly of mild intensity, were recorded in 9 patients in each MT group. A total of 7 patients had to discontinue treatment because of its inefficiency.Conclusion. All the four therapy regimens demonstrated a significant efficiency in patients with early RA; the total remission rate was 24%. The combination  of MT and GC produced the most pronounced effect. The tolerability of treatment was good in all groups

Quality of life before autologous stem cells transplantation as prognostic factor in patients with malignant lymphomas

<p>Currently high-doses chemotherapy (HD-PCT) + autologous hematopoietic stem cells transplantation (auto-HSCT) is the treatment of<br />choice in patients with recurrent and progressive lymphomas. Most of quality of life (QoL) studies in lymphomas patients received HSCT limited on parameters dynamics assessment in the early and late post-transplant period. Aim of this study was to evaluate the QoL parameters and their prognostic significance in lymphoma patients before transplantation. 124 patients with lymphomas (non-Hodgkin lymphomas – 45 patients, Hodgkin's lymphoma – 79 patients) who received HD-PCT + auto-HSCT were included in the study: men – 42.7 % (n = 53), women – 57.3 % (n = 71), median age – 34 years (19–65 years). Patients’ heterogeneity before transplantation regarding quality of life has been revealed. Almost 1/3 of patients showed a significant reduction in the integral index of QoL. Insignificant differences between patients with chemosensitivity and chemoresistant lymphomas regarding QoL before HD-PCT + auto-HSCT were shown. We also analyzed the outcomes of studied patients received HD-PCT + auto-HSCT. With a median follow-up of 18 months, overall survival after transplantation was 72 % (95 % CI 56–84); event-free survival – 64 % (95 % CI 53,3–73,2).<br />Overall and event-free survivals were significantly higher in patients with chemosensitive lymphoma compared with chemoresistance tumor. Differences in the survival rates between patients with no or negligible decrease of QoL integral index and with significant reduction of it also were found. Revealed differences in overall and event-free survival between the groups allowed the first group considered as patients with a favorable prognosis, and the second group – as patients with poor prognosis regarding the transplantation outcome.</p

Application of Biocompatible Noble Metal Film Materials to Medical Implants: TiNi Surface Modification

Recently, film materials based on the combination of noble metals have showed promising results for surface modification of medical implants, allowing both to improve biocompatibility and to acquire the increased antibacterial effect. An important challenge here is to combine the developed coating morphology, which is favorable for biological response, with a high protective function, which, on the contrary, requires a compact coating microstructure. In this work, we aimed to solve this problem with respect to the TiNi implant material. We have tested two types of compact thin sublayers: Iridium (Ir’), formed by metal-organic chemical vapor deposition (MOCVD), and gold (Au), formed by physical vapor deposition (PVD). Subsequently these sublayers were coated with a developed-columnar-iridium (Ir) by MOCVD. Features of the microstructure, chemical and phase composition of all these film materials were studied using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The changes in the characteristics of TiNi martensitic transformation due to MOCVD experiments were also studied by differential scanning calorimetry (DSC). The biocompatibility of Ir’/TiNi, Au/TiNi, Ir/Ir’/TiNi, Ir/Au/TiNi samples was assessed by cytoxicity testing (Man-1 cells) and measuring of nickel content in the biological extracts. The application of both sublayers effectively reduces the release of nickel, which was previously shown for Ir/TiNi samples. This prevents the toxic effect. Note that the Ir’ sublayer better protects against nickel release, while the Au sublayer promotes cell proliferation