Exact analytical solution of the problem of current-carrying states of the Josephson junction in external magnetic fields

The classical problem of the Josephson junction of arbitrary length W in the presence of externally applied magnetic fields (H) and transport currents (J) is reconsidered from the point of view of stability theory. In particular, we derive the complete infinite set of exact analytical solutions for the phase difference that describe the current-carrying states of the junction with arbitrary W and an arbitrary mode of the injection of J. These solutions are parameterized by two natural parameters: the constants of integration. The boundaries of their stability regions in the parametric plane are determined by a corresponding infinite set of exact functional equations. Being mapped to the physical plane (H,J), these boundaries yield the dependence of the critical transport current Jc on H. Contrary to a wide-spread belief, the exact analytical dependence Jc=Jc(H) proves to be multivalued even for arbitrarily small W. What is more, the exact solution reveals the existence of unquantized Josephson vortices carrying fractional flux and located near one of the junction edges, provided that J is sufficiently close to Jc for certain finite values of H. This conclusion (as well as other exact analytical results) is illustrated by a graphical analysis of typical cases.Comment: 21 pages, 9 figures, to be published in Phys. Rev.

Immunohistochemical features of the bone tissue of the lower extremities in patients with type 2 diabetes mellitus

Background: Diabetic neuroosteoarthropathy is a serious disabling complication of diabetes mellitus, which, in the absence of timely correct treatment, can lead to high amputations of the affected limb. At present, the reasons and mechanism of the development of Charcot’s foot are not completely clear. It is extremely important to determine the pathophysiological mechanisms of DNOAP formation and to search for reliable markers-predictors of this pathology.Aim: To study the immunohistochemical characteristics of the bone tissue of the lower extremities in patients with diabetic neuroosteoarthropathy in comparison with patients with diabetes mellitus without this pathology.Materials and methods: During the foot surgery, a bone fragment of the foot was harvested for immunohistochemical study of receptor markers for PINP, PIIINP, and RAGE in the group of patients with DNOAP compared with the control group.Results: The study included 20 patients with type 2 diabetes mellitus and were divided into 2 groups: 10 patients with DNOAP made up group 1, 10 patients without DNOAP — group 2.Patients in both groups were comparable in AGE, experience with type 2 diabetes, and glycemic control.During the immunohistochemical study, a significant increase in the staining intensity of receptor markers for PINP, PIIINP, and AGE was recorded in the group of patients with DNOAP compared with the control group (p <0.05).Conclusion: For the first time, an immunohistochemical study of markers of bone resorption and AGE was carried out in persons with DNOAP. The results obtained indicate impaired collagen formation and, as a consequence, impaired bone formation and bone resorption in patients with DNOAP: in group 1, a statistically significant increase in the expression of PINP, PIIINP, and RAGE was revealed

Particular Characteristics of the Synthesis of Titanium Nitride Nanopowders in the Plasma of Low Pressure Arc Discharge

The method of producing TiN nanopowders in the plasma of low pressure arc discharge in nitrogen atmosphere is discussed. The influence of gas pressure on nanopowder dispersion is studied. It is shown that the particles have nanometer size and a narrow particle size distribution

Симультанное хирургическое лечение больных почечно-клеточным раком с конкурирующей патологией сердца

The authors analyze the immediate results of 8 simultaneous operations, 4 of these under conditions of artificial circulation, in patients with renal cell carcinoma concomitant with heart diseases. The immediate results were satisfactory, with good functional parameters. Due to simultaneous operations the incidence of intra- and postoperative cardiovascular complications is reduced, the progress of the tumor process between different stages of treatment is arrested, early radical interventions for tumor removal becomes possible, and the hospitalization period is shorter in comparison with staged operations.

DNA Repair in Human Pluripotent Stem Cells Is Distinct from That in Non-Pluripotent Human Cells

The potential for human disease treatment using human pluripotent stem cells, including embryonic stem cells and induced pluripotent stem cells (iPSCs), also carries the risk of added genomic instability. Genomic instability is most often linked to DNA repair deficiencies, which indicates that screening/characterization of possible repair deficiencies in pluripotent human stem cells should be a necessary step prior to their clinical and research use. In this study, a comparison of DNA repair pathways in pluripotent cells, as compared to those in non-pluripotent cells, demonstrated that DNA repair capacities of pluripotent cell lines were more heterogeneous than those of differentiated lines examined and were generally greater. Although pluripotent cells had high DNA repair capacities for nucleotide excision repair, we show that ultraviolet radiation at low fluxes induced an apoptotic response in these cells, while differentiated cells lacked response to this stimulus, and note that pluripotent cells had a similar apoptotic response to alkylating agent damage. This sensitivity of pluripotent cells to damage is notable since viable pluripotent cells exhibit less ultraviolet light-induced DNA damage than do differentiated cells that receive the same flux. In addition, the importance of screening pluripotent cells for DNA repair defects was highlighted by an iPSC line that demonstrated a normal spectral karyotype, but showed both microsatellite instability and reduced DNA repair capacities in three out of four DNA repair pathways examined. Together, these results demonstrate a need to evaluate DNA repair capacities in pluripotent cell lines, in order to characterize their genomic stability, prior to their pre-clinical and clinical use

Clinical features of post-COVID-19 period. Results of the international register “Dynamic analysis of comorbidities in SARS-CoV-2 survivors (AKTIV SARS-CoV-2)”. Data from 6-month follow-up

Aim. To study the clinical course specifics of coronavirus disease 2019 (COVID-19) and comorbid conditions in COVID-19 survivors 3, 6, 12 months after recovery in the Eurasian region according to the AKTIV register. Material and methods.The AKTIV register was created at the initiative of the Eurasian Association of Therapists. The AKTIV register is divided into 2 parts: AKTIV 1 and AKTIV 2. The AKTIV 1 register currently includes 6300 patients, while in AKTIV 2 — 2770. Patients diagnosed with COVID-19 receiving in- and outpatient treatment have been anonymously included on the registry. The following 7 countries participated in the register: Russian Federation, Republic of Armenia, Republic of Belarus, Republic of Kazakhstan, Kyrgyz Republic, Republic of Moldova, Republic of Uzbekistan. This closed multicenter register with two nonoverlapping branches (in- and outpatient branch) provides 6 visits: 3 in-person visits during the acute period and 3 telephone calls after 3, 6, 12 months. Subject recruitment lasted from June 29, 2020 to October 29, 2020. Register will end on October 29, 2022. A total of 9 fragmentary analyzes of the registry data are planned. This fragment of the study presents the results of the post-hospitalization period in COVID-19 survivors after 3 and 6 months. Results. According to the AKTIV register, patients after COVID-19 are characterized by long-term persistent symptoms and frequent seeking for unscheduled medical care, including rehospitalizations. The most common causes of unplanned medical care are uncontrolled hypertension (HTN) and chronic coronary artery disease (CAD) and/or decompensated type 2 diabetes (T2D). During 3- and 6-month follow-up after hospitalization, 5,6% and 6,4% of patients were diagnosed with other diseases, which were more often presented by HTN, T2D, and CAD. The mortality rate of patients in the post-hospitalization period was 1,9% in the first 3 months and 0,2% for 4-6 months. The highest mortality rate was observed in the first 3 months in the group of patients with class II-IV heart failure, as well as in patients with cardiovascular diseases and cancer. In the pattern of death causes in the post-hospitalization period, following cardiovascular causes prevailed (31,8%): acute coronary syndrome, stroke, acute heart failure. Conclusion. According to the AKTIV register, the health status of patients after COVID-19 in a serious challenge for healthcare system, which requires planning adequate health system capacity to provide care to patients with COVID-19 in both acute and post-hospitalization period