Spin-polarized tunneling spectroscopic studies of the intrinsic heterogeneity and pseudogap phenomena in colossal magnetoresistive manganite La_{0.7}Ca_{0.3}MnO_{3}

Spatially resolved tunneling spectroscopic studies of colossal magnetoresistive (CMR) manganite $\rm La_{0.7}Ca_{0.3}MnO_3$ (LCMO) epitaxial films on $\rm (LaAlO_3)_{0.3}(Sr_2AlTaO_6)_{0.7}$ substrate are investigated as functions of temperature, magnetic field and spin polarization by means of scanning tunneling spectroscopy. Systematic surveys of the tunneling spectra taken with Pt/Ir tips reveal spatial variations on the length scale of a few hundred nanometers in the ferromagnetic state, which may be attributed to the intrinsic heterogeneity of the manganites due to their tendency towards phase separation. The electronic heterogeneity is found to decrease either with increasing field at low temperatures or at temperatures above all magnetic ordering temperatures. On the other hand, spectra taken with Cr-coated tips are consistent with convoluted electronic properties of both LCMO and Cr. In particular, for temperatures below the magnetic ordering temperatures of both Cr and LCMO, the magnetic-field dependent tunneling spectra may be quantitatively explained by the scenario of spin-polarized tunneling in a spin-valve configuration. Moreover, a low-energy insulating energy gap $\sim 0.6$ eV commonly found in the tunneling conductance spectra of bulk metallic LCMO at $T \to 0$ may be attributed to a surface ferromagnetic insulating (FI) phase, as evidenced by its spin filtering effect at low temperatures and vanishing gap value above the Curie temperature. Additionally, temperature independent pseudogap (PG) phenomena existing primarily along the boundaries of magnetic domains are observed in the zero-field tunneling spectra. The PG becomes strongly suppressed by applied magnetic fields at low temperatures when the tunneling spectra of LCMO become highly homogeneous. These findings suggest that the occurrence PG is associated with the electronic heterogeneity of the manganites.Comment: 15 pages, 15 figures. Published in Physical Review B. Corresponding author: Nai-Chang Yeh (E-mail: [email protected]

Innovative material based on wood waste for application in special purpose vehicles

The article presents innovative composite wood material DS-1 with a powder binding, which is used in special purpose vehicles. Vehicles for transporting radioactive waste for its recycling and disposal, and radiodiagnostics mobile complexes intended for conducting massive X-ray have been considered. The composition of material DS-1 has been revealed, experiments have been listed and a table with physical and mechanical properties has been given. Relying on experimental analysis data it can be concluded that implementation of innovative composite material DS-1 with a powder binder using barium sulphate helps solve the problem of lead replacement with lighter environmentally friendly material and contributes to complex use of wood raw materials Using a low-toxic binder in the material obtained makes its production innocuous and environmentally friendly and and solves a number of economic and energy-saving problems. © 2019 Published under licence by IOP Publishing Ltd

Creation, doubling, and splitting, of vortices in intracavity second harmonic generation

We demonstrate generation and frequency doubling of unit charge vortices in a linear astigmatic resonator. Topological instability of the double charge harmonic vortices leads to well separated vortex cores that are shown to rotate, and become anisotropic, as the resonator is tuned across resonance

Efficiency of the Left Atrial Appendage Thrombus Dissolution in Patients with Persistent Nonvalvular Atrial Fibrillation with Warfarin or Direct Oral Anticoagulants Therapy

Aim. Compare the incidence of the left atrial appendage (LAA) thrombus dissolution in patients with persistent nonvalvular atrial fibrillation receiving warfarin and direct oral anticoagulants (DOAC).Materials and methods. 68 patients with persistent nonvalvular atrial fibrillation were included in a retrospective study (age was 59.7±9.8 years, 60.3% men), in whom at least one repeated transesophageal echocardiographic examination was performed after detecting a thrombus. After detecting a thrombus in the LAA, 37 (54.4%) patients started or continued taking warfarin in doses that ensure the INR maintenance at the level of 2-3, 14 (20.6%) started or continued taking dabigatran at a dose of 150 mg 2 times/day, 14 (20.6%) started or continued taking rivaroxaban 20 mg 1 time/day and 3 (4.4%) started or continued taking apixaban 5 mg 2 times/day. Repeated transesophageal echocardiographic examination was performed on average 33.3±14.2 days after the first one.Results. Dissolution of a previously identified thrombus was found in 26 (83.9%) of 31 patients receiving DOAC and in 19 (51.4%) of 37 patients receiving warfarin (p=0.011). The logistic regression analysis showed that the chances of a thrombus dissolution in LAA while taking DOAC are 14.8 times (95% confidence interval [CI] was 2.469-88.72) higher than while taking warfarin. The size and the rate at which blood is expelled from the LAA also have an independent influence on the chances of thrombus dissolution. An increase in the size of a thrombus by 1 mm reduces the chances of a thrombus dissolution by 1.136 (95% CI was 1.040-1.244) times, and an increase in the rate of blood expulsion from the LAA by 1 cm/sec increases these chances by 1.105 (95% CI was 1.003-1.219) times.Conclusion. In the present study, the incidence of the LAA thrombus dissolution in patients with persistent nonvalvular atrial fibrillation while receiving DOAC was higher than while receiving warfarin

Forecasting the development of mechanical engineering using the system dynamics method

At modern conditions of world economy tendencies, the connections between subjects of economy are becoming more difficult and closer. In particular, if in the past were spread hard forms of private ownership of enterprises at present-day world is going conversion to more flexible and mobile composition of subjects' activities. Computer simulation modeling is giving the best results at the areas were the participants of social and economic activities are spending significant efforts and sufficiently much time for visuality playing and analysis of possible variants of the development of the events. The more difficult is the situation the more objects, factors, and possible variants of events' progress is necessary to play in different combinations between together and bigger effect possible to expect from application of simulation model for analyzing of the situation and for searching and making optimized decisions. The application of system dynamics method allows executing forecasting of economic agents including the sectors of economy. © 2020 American Institute of Physics Inc.. All rights reserved

Left atrial strain in assessing heart failure with preserved ejection fraction in hypertensive patients

Aim. To compare the results of diagnosing heart failure with preserved ejection fraction (HFpEF) in patients with hypertension (HTN) according left atrial (LA) strain values with the results obtained using the H2FPEF score and diastolic stress testing (DST).Material and methods. The study included 293 patients with previously established HTN who were examined due to complaints of shortness of breath and/or palpitations (men, 97 (33,5%), mean age, 62,0 (55,0; 67,0) years). All patients underwent transthoracic echocardiography with the assessment of LA strain parameters and probability of HFpEF using the H2FPEF score. Eighty five patients with an intermediate probability of HFpEF underwent DST.Results. A low probability of HFpEF according to the H2FPEF score was registered in 35 (11,9%) patients, uncertain — in 206 (70,3%), high — in 52 (17,7%). DST was negative in 43 (50,6%) and positive in 42 (49,4%) patients with an intermediate probability of HFpEF. LA strain in the reservoir phase in patients with a low probability of HFpEF averaged (median and interquartile interval) 28,0 (23,6; 31,5)%, while in patients with an intermediate probability and negative DST — 24,0 (22,0; 26,8)%, with an intermediate probability and positive DST — 20,0 (18,0; 21,0)%, and with a high probability of HFpEF — 19,6 (16,9; 21,8)%. HFpEF was diagnosed in 94 patients, including 52 with a high probability on the H2FPEF score and 42 with an intermediate probability and positive DST. The diagnosis of HFpEF was ruled out in 78 patients, including 35 with a low probability on the H2FPEF score and 43 with an intermediate probability and negative DST. Further, 172 patients with confirmed or excluded HFpEF were randomly divided into two equal cohorts. In the training cohort, HFpEF was diagnosed in 44 (51,2%) patients, in the validation cohort — in 50 (58,1%). ROC analysis performed on the training cohort for the LA strain in reservoir phase showed AUC of 0,920 (95% confidence interval (CI), 0,842-0,968) and cut-off point of 21,5%. In the training cohort, the results of HFpEF diagnosis using the indicated criterion coincided with those using H2FPEF score and DST in 86,1% (95% CI, 77,2-91,8) of cases. The Cohen’s kappa was 0,721 (95% C,I 0,575-0,868). In the validation cohort, agreement was observed in 84,9% (95% CI 75,8-91,0) of cases with Cohen’s kappa of 0,702 (95% CI 0,553-0,851).Conclusion. In hypertensive patients, the diagnosis of HFpEF made on the basis of a decrease in the LA strain in reservoir phase to ≤21,5%, is in good agreement with the diagnosis made using the H2FPEF score and DST

Forecasting the SST space-time variability of the Alboran Sea with genetic algorithms

We propose a nonlinear ocean forecasting technique based on a combination of genetic algorithms and empirical orthogonal function (EOF) analysis. The method is used to forecast the space-time variability of the sea surface temperature (SST) in the Alboran Sea. The genetic algorithm finds the equations that best describe the behaviour of the different temporal amplitude functions in the EOF decomposition and, therefore, enables global forecasting of the future time-variability.Comment: 15 pages, 3 figures; latex compiled with agums.st

Implantation surgery for the treatment of urinary incontinence. Analysis of the immediate and long-term complications

In the clinic of urology Federal State Budgetaiy Institution of Higher Professional Education «Urals State Medical University» of the Minisby of Healthcare of the Russian Federation on the basis of «Sverdlovsk regional clinical hospital № 1»conducted a retrospective analysis of complications after implantation correction of urinary incontinence in men and women through a variety of sling operations, as well as the installation of an artificial urinary sphincter. Achieved 44 retrobulbar sling implantation systems Argus T and artificial sphincter AMS-800 of the bladder in men and 536 different systems implanted like TVTI TVT-0 in women with stress urinary incontinence. We obtained results: success was achieved in 66.7% of patients after implantation retrobulbar sling (complications was observed in 13.3%) patients with bladder sphincter implanted clinical efficacy was 76% (complications was observed abserved 172%); women in 97.8% of cases managed to achieve a positive effect, and eliminate stress incontinence, and the incidence of complications was 9.6% (total 49 patients). We came to the conclusion about the importance of proper selection of readings to a variant of implant technique in men, that is the key tojhe success of the operation, correcting urinary incontinence. Implantation method synthetic slings at stessovom incontinence in women is a minimally invasive, safe, low level of postoperative complications.В клинике урологии ФГБОУ ВО УГМУ Минздрава России на базе ГБУЗ СО «Свердловская ОКБ №1» проведен ретроспективный анализ осложнений после имплантационной коррекции недержания мочи у мужчин и женщин с помощью различных слинговых операций, а также установки искусственного сфинктера мочевого пузыря. Выполнено 44 имплантации систем ретробульбарного слинга Аргус Т и искусственного сфинктера мочевого пузыря AMS-800 у мужчин, атакже имплантировано 536 различных систем TVT/TVT-0 у женщин со стрессовым недержанием мочи. Нами получены реультаты: успех был достигнут у 66,7% пациентов после имплантации ретробульбарного слинга (осложнения наблюдались в 13,3%), у пациентов с имплантированным сфинктером мочевого пузыря клиническая эффективность составила 76% (осложнения наблюдались в 17,2%); у женщин в 97,8% случаев удалось добиться положительного эффекта и ликвидировать стрессовое недержание мочи, при этом частота осложнений составила 9,6% (всего 49). Мы пришли к выводу о важности правильного выбора показания к варианту имплантационной методики у мужчин, что является залогом успеха операции, коррегирующей мочевую инконтиненцию. Метод имплантации синтетической слингов при стрессовом недержании мочи у женщин является малоинвазивным, безопасным, с низким уровнем послеоперационных осложнений

Interplay of unsteady aerodynamics and flight dynamics of transport aircraft in icing conditions

Airframe icing causes significant degradation of aerodynamic characteristics and influences the flight safety. Wind tunnel study of longitudinal steady and unsteady aerodynamic characteristics of a transport aircraft in icing conditions is carried out in order to develop mathematical model of aerodynamics in the extended flight envelope. The wind tunnel results are validated through flight tests conducted for the real aircraft. Large, glaze-horn ice shapes, corresponding to holding flight phase, are considered. Influence of an ice protection system as well as its failure is examined. Effect of icing on the unsteady aerodynamics characteristics is studied not only through wind tunnel tests but also via analysis of subsequent influence on the flight dynamics of the aircraft. The conducted study shows that the ice shapes of the holding phase leads to reduced stall angle of attack (AoA), maximum lift, and longitudinal damping. Flight dynamics analysis demonstrates that dangerous aircraft behaviour in the form of high AoA departure and limit cycle oscillations (LCO) can be observed at smaller elevator deflections for the iced aircraft. Taking into account icing influence on the unsteady aerodynamics in the flight dynamics simulations revealed degradation of the dynamic response and deterioration of phase portraits of the system. Even for small AoA and elevator deflection the aircraft might be trapped into the basin of attraction of high-AoA LCO. In addition, incorporating icing effects in unsteady aerodynamics manifest larger amplitude of LCO