528 research outputs found
FEATURES OF TAKEOFF PHASE IN LONG JUMPS WITH VARIOUS RUN-UP LENGTHS
The aim of the present study was to compare the kinematic characteristics of jumper's movements in long jumps with short, middle and extended run-ups. For this purpose three male and four female jumpers performed two three strides, eight strides and twelve strides run-up long jumps. All trials were captured on high-speed video. The results of the 2D analysis indicated that ground contact time and takeoff angle were significantly larger when the run-up was short. Also, the distance from the center of gravity to the heel in the horizontal plane and the knee angle at touchdown, as well as the maximum knee flexion of the takeoff leg during takeoff, were significantly smaller when the run-up was short. The heights of the center of gravity at touchdown and takeoff were constant in long jumps with various run-up lengths
Methodological aspects of the development of technological entrepreneurship and implementation of financial support tools in Russian universities
This article describes the development of methods of identification and support of communication between a developer and a technological entrepreneur. It is to promote university research activities. Special attention is paid to stimulating inventive activity and a university need in evolution of a developer from an inventor to series developmental engineer. The importance of an entrepreneurial path has been empathized. Financial tools of attraction of alternative funding for university innovative projects (e.g. endowment fund) have been analyzed
Optimal rotor blade swirl law for the last stage of a stationary turbine with an axial diffuser
The flow kinetic-energy conversion into the pressure-forces field in the outlet turbine diffuser increases the heat drop to the last stage, generating additional power. The recovery properties of the diffuser are determined predominantly by the inlet boundary conditions of the flow formed by the last turbine stage. This study aims to demonstrate the influence of the last turbine stage swirl law on the boundary conditions formation at the diffuser inlet. The aerodynamics of the “turbine stage–exhaust diffuser” system (“S–D” system) was studied by an experimental method. The experimental results validated the numerical model of the flow in the “S–D” system. The stage's integral characteristics, the diffuser, and the “S–D” system were obtained for three system geometry variants. The results of the experiments revealed the indisputable advantage of the “negative” swirl law of the last turbine stage. An analysis of the flow structure based on the numerical simulation results revealed the details of the advantages of the boundary conditions at the diffuser inlet formed by the stage with a “negative” swirl compared with the stage with the traditional swirl law. Based on the results, recommendations for the “S–D” system design of powerful stationary gas turbines are proposed
Methodological aspects of the development of technological entrepreneurship and implementation of financial support tools in Russian universities
This article describes the development of methods of identification and support of communication between a developer and a technological entrepreneur. It is to promote university research activities. Special attention is paid to stimulating inventive activity and a university need in evolution of a developer from an inventor to series developmental engineer. The importance of an entrepreneurial path has been empathized. Financial tools of attraction of alternative funding for university innovative projects (e.g. endowment fund) have been analyzed
Kinetic determination of thiocyanate by the reaction of bromate with crystal violet immobilized in a polymethacrylate matrix
Abstract: A procedure is proposed for the kinetic solid-phase spectrophotometric determination of thiocyanate using a polymethacrylate matrix. The procedure is based on the Landolt reaction between Crystal Violet immobilized in a polymethacrylate matrix and a bromate oxidizer, accompanied by the discoloration of the indicator in the matrix. During some induction period after the introduction of thiocyanate into the test solution, the dye in the matrix is not discolored. The duration of the induction period is proportional to the concentration of thiocyanate in the solution. The change in the color of the polymethacrylate matrix was recorded by measuring its absorbance at 600 nm. The developed procedure ensures the determination of thiocyanate in the concentration range 0.025–12 mg/L, depending on the Crystal Violet concentration in the matrix. The limit of detection calculated according to the 3s-test is 0.02 mg/L with the indicator concentration in the matrix of 0.06 mg/g. A possibility of using the proposed procedure for the determination of thiocyanate in near-wellbore water is shown
To the Anniversary of Prof. A. Wacke
В статье освещаются заслуги профессора А. Ваке перед отечественным антиковедением. In the article services of Professor A. Wacke to Russian classical studies are illuminated.Полный текст статьи размещен по разрешению редакционной коллегии журнала IVS ANTIQVVM
Impact of endoscopic enucleation of the prostate with thulium fiber laser on the erectile function
Abstract Background The impact of number of endoscopic enucleation of the prostate techniques (holmium laser enucleation - HoLEP for example) on erectile function have already been investigated. However, the thulium-fiber laser, in this setting remains unstudied. In this study, we compared sexual function outcomes in patients with benign prostatic hyperplasia (BPH) treated with transurethral resection of the prostate (TURP) or thulium-fiber laser enucleation (ThuFLEP). Methods We performed a retrospective analysis of patients who underwent transurethral resection and endoscopic enucleation of the prostate for BPH; inclusion criteria was the presence of infravesical obstruction (IPSS > 20, Qmax < 10 mL/s). Erectile function (EF) was assessed using the International Index of Erectile Function (IIEF-5) both prior to endoscopic examination, and six months after. Results A total of 469 patients with BPH were included in the study; of these, 211 underwent to ThuFLEP, and 258 TURP. Preoperative IIEF-5 in TURP and ThuFLEP groups were 11.7 (±4.5) and 11.1 (±5.0), respectively (p = 0.17). At six month the IIEF-5 score was unchanged (p = 0.26 and p = 0.08) and comparable in both groups (p = 0.49). However, mean IIEF-5 score shown significant increase of 0.72 in ThuFLEP group, comparing to decrease of 0.24 in TURP patients (p < 0.001). Conclusions Both TURP and ThuFLEP are effective modalities in the management of infravesical obstruction due to BPH. At six months follow-up after surgery, both techniques lead to comparable IIEF-5 score. However, our results demonstrated that the ThuFLEP is more likely to preserve the erectile function leading to increase of IIEF-5 at six months in contrast to TURP which lead to slight drop in IIEF-5 score
Memory of Helena Vissarionovna Kulagina
Краткий очерк, посвящённый вкладу Е.В. Кулагиной в отечественное антиковедение. The short essay on the contribution of E.V. Kulagina in the Russian Antiquitas Studie
Temperature Behavior of Precursor Clusters at the Pre-Crystallization Phase of K(H<sub>2</sub>PO<sub>4</sub>) Studied by SAXS
Elementary building blocks for the growth of KDP crystals were established. The solution of potassium dihydrogen phosphate (KH2PO4–KDP) has been experimentally studied by the small-angle X-ray scattering (SAXS) method. The analysis of SAXS data in the temperature range of 2.5–90 °C using a set of models of 3D fragments of the crystal structure showed that the saturated solution contains above K+, H2PO4− and KH2PO4 monomers, as well as mainly octamers. The 3D model of the octamer isolated from the crystal structure has dimensions of 17.443 Å along the [001] axis and 5.963 Å along the [100] and [010] axes. As the temperature is decreased, starting from the saturation temperature of the solution, the volume fraction of octamers sharply increases while the volume fraction of monomers decreases. The results indicate that the monomers and octamers represent major components in the solution with the presence of minor populations of other oligomers. The significant dominance of octamers in the supersaturated solution indicates that they are elementary building blocks for the growth of KDP crystals of tetragonal modification
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