Dynamics in a noncommutative phase space

Dynamics has been generalized to a noncommutative phase space. The noncommuting phase space is taken to be invariant under the quantum group $GL_{q,p}(2)$. The $q$-deformed differential calculus on the phase space is formulated and using this, both the Hamiltonian and Lagrangian forms of dynamics have been constructed. In contrast to earlier forms of $q$-dynamics, our formalism has the advantage of preserving the conventional symmetries such as rotational or Lorentz invariance.Comment: LaTeX-twice, 16 page

On the Wigner function of the relativistic finite-difference oscillator in an external field

The phase-space representation for a relativistic linear oscillator in a homogeneous external field expressed through the finite-difference equation is constructed. Explicit expressions of the relativistic oscillator Wigner quasi-distribution function for the stationary states as well as of states of thermodynamical equilibrium are obtained and their correct limits are shown.Comment: 12 pages, 6 figures, IOP styled LaTeX, to be published in Journal of Physics

Hydrodynamic bidimensional stability of detonation wave solutions for reactive mixtures

The structure of a planar detonation wave is analyzed for an Eulerian mixture of ideal gases undergoing the symmetric reversible explosive reaction A1 + A1 = A2 + A2. The chemical rate law is derived from the reactive Boltzmann equation, showing a detailed chemical kinetics in terms of a second-order reaction rate. The hydrodynamic bidimensional stability of the detonation wave is also investigated using a normal mode approach, when small time-space transverse disturbances affect the shock wave location. A suitable numerical technique is here proposed in order to solve the stability problem and numerical results are provided illustrating the detonation wave structure and its instability spectrum.The paper is partially supported by Brazilian Research Council (CNPq), by Italian Research Council GNFM-INdAM, and by Portuguese Funds of FCT, CMAT project UID/MAT/00013/2013

ON ONE APPROACH TO THE CALCULATION OF THE BITUMEN MELTING PROCESS

The paper presents a technique for numerical modeling of the process of heating bitumen with its transfer to a characteristic liquid state, when convective flows of the medium are observed. The mathematical model of the process is formulated on the basis of the two-phase Stefan problem with the use of equations that determine the free motion of particles in the melt. The calculation results and conclusions are presented.В работе представлена методика численного моделирования процесса разогрева битума с переводом его в характерное жидкое состояние, когда наблюдаются конвективные потоки среды. Математическая модель процесса сформулирована на основе двухфазной задачи Стефана с привлечением уравнений, определяющих свободное движение частиц в расплаве. Приведены результаты расчетов и выводы

METHOD OF CALCULATING THE PROCESSES OF ICE GENERATION

The article presents an approach to the numerical implementation of the two-phase Stefan problem, useful in creating new and improving existing technical devises for ice production. The features of the author’s calculation method, which favorably distinguish it from similar developments, are given. The results of calculations are presented and they are discussed.В статье представлен подход к численной реализации двухфазной задачи Стефана, полезный при создании новых и совершенствовании существующих технических устройств для получения льда. Приведены особенности авторской методики расчета, выгодно отличающие ее от подобного рода разработок. Представлены результаты расчетов и проведено их обсуждение

Endoscopic treatment for bulbar-membranous urethral obliteration: evaluation of the efficacy and safety

Introduction. The problem of endoscopic treatment for urethral strictures and obliterations remains unresolved. It is necessary to note that the effectiveness depends not only on the right indications, but also on the surgical technique and the study of the postoperative period management.Objective. To evaluate the efficacy and safety of endoscopic treatment of patients with bulbar-membranous urethral obliteration.Materials and methods. The study included 103 patients aged 20 to 89 years with bulbar-membrane urethral obliteration, who, for some reason or another, cannot perform urethroplasty. The patients underwent endoscopic recanalization of the urethra under X-ray control with further circular transurethral electroresection (TUR) of the scar tissues in the urethral obliteration zone (after 6 – 7 days).Results. The average age of the patients was 61.1 ± 18.3 years. After the operation, self-urination was restored in all patients. The average maximum urine flow rate (Q max) before discharge from the hospital was 12.6 ± 0.5 ml/s. Throughout the follow-up period, Q max tended to increase and at the end of the study (36 months) reached values of 16.5 ± 0.5 ml/s. During the first year of follow-up, 18 (17.5%) patients developed recurrent urethral stricture. Seventeen (16.5%) patients underwent repeated circular TUR of scar tissue in the zone of recurrent stricture. The effectiveness of the treatment was 90.0%.Conclusion. Endoscopic urethral recanalization followed by TUR of scar tissue in the obliteration zone is an effective and safe method in the treatment of bulbar-membranous urethral obliteration with length less than 1.0 cm

Разработка конструкции щелевого сельскохозяйственного распылителя и исследование его выходных параметров

It is shown that the use of low-quality sprayers for pesticide application can lead to the yield decrease and negative environmental consequences. The use of worn nozzles is noted to reduce the efficiency of plant treatment, since the deviation from the dosage norm of plant protection products reaches 30-60 percent. It is noted that foreign-made sprayers are most often used in Russia, since there are no domestic analogues providing similar output parameters. (Research purpose) To investigate the output parameters of the developed slotted agricultural sprayer and compare them with the performance of advanced imported analogues. (Materials and methods) A prototype model of the developed sprayer was made of bronze using mechanical treatment. It was examined on a special test bench in comparison with a reference polymer sprayer. Using optical microscopy the flow rate of the working fluid and the spray angle were measured, as well as the dimensions of the sprayer nozzle. (Results and discussion) It was found that, on average, in the prototype sprayer made of bronze, the flow rate of the working fluid is 1.7 times greater and the spray angle is 37.16 degrees less than those of a reference polymer sprayer. The examination of the spray nozzles by an optical microscope revealed some differences in shape and size. (Conclusions) The developed design of the sprayer reveals a need for improvement: the nozzle shape should be modified to ellipsoid; the nozzle size should be reduced.Показали, что применение некачественных распылителей для внесения пестицидов может привести к снижению урожайности и негативным экологическим последствиям. Отметили, что использование изношенных форсунок ухудшает эффективность обработки растений, так как отклонение от нормы расхода средств защиты растений достигает 30-60 процентов. Отметили, что наиболее часто в России применяют распылители иностранного производства, поскольку отечественных аналогов, обеспечивающих схожие выходные параметры, не существует. (Цель исследования) Исследовать выходные параметры разработанного щелевого сельскохозяйственного распылителя и сравнить их с показателями передовых импортных аналогов. (Материалы и методы) Опытный образец разработанного распылителя изготовили из бронзы с применением механической обработки. Исследовали его на специальном стенде в сравнении с эталонным полимерным распылителем. Измерили расход рабочей жидкости и угол распыла, а также размеры сопла, для чего применили оптическую микроскопию. (Результаты и обсуждение) Установили, что в среднем расход рабочий жидкости у опытного образца распылителя, изготовленного из бронзы, в 1,7 раза больше, чем у эталонного полимерного распылителя, а угол распыла меньше на 37,16 градуса. Исследование сопел распылителей с помощью оптического микроскопа позволило выявить различия в форме и размерах. (Выводы) Определили, что разработанная конструкция распылителя нуждается в доработке: форма сопла должна быть скорректирована до эллипсовидной, размеры сопла следует уменьшить

Прямая морфологическая детекция Borrelia burgdorferi в мышечных биоптатах: возможность связи нервно-мышечной патологии с боррелиозом

The authors examined 40 muscle biopsy specimens taken from patients with neuromuscular symptoms when the diagnosis was unestablished or presumptive. Eighteen of them exhibited foci of muscle fiber damage with the presence of spirochete-like structures in the semithin tissue sections. Electron microscopy of these areas detected Borrelia as vegetative and diverse L-forms. Immunocytochemical techniques usingantibodies to Borrelia burgdorferi antigens confirmed that the spirochetes belonged to this species. This allows one to consider borreliosis as an etiological or complicating factor of neuromuscular pathology and to recommend the above morphological methods for the diagnosis of neuromuscular diseases of unknown origin.Исследовано 40 биоптатов мышц, взятых у больных с нервно-мышечной симптоматикой при неустановленном или предположительном диагнозе. В 18 из них в полутонких срезах ткани обнаружены очаги повреждения мышечных волокон с наличием спирохетоподобных структур. При электронной микроскопии этих участков были выявлены боррелии в виде вегетативных и разнообразных L-форм. Применение методов иммуноцитохимии с антителами к антигенам Borrelia burgdorferi подтвердило принадлежность спирохет к данному виду. Это позволило считать этиологическим или осложняющим фактором нервно-мышечной патологии боррелиоз, а также рекомендовать применять указанные морфологические методы как диагностические в случаях нервно-мышечных заболеваний неясного происхождения

Effect of Initial Disturbance on The Detonation Front Structure of a Narrow Duct

The effect of an initial disturbance on the detonation front structure in a narrow duct is studied by three-dimensional numerical simulation. The numerical method used includes a high resolution fifth-order weighted essentially non-oscillatory scheme for spatial discretization, coupled with a third order total variation diminishing Runge-Kutta time stepping method. Two types of disturbances are used for the initial perturbation. One is a random disturbance which is imposed on the whole area of the detonation front, and the other is a symmetrical disturbance imposed within a band along the diagonal direction on the front. The results show that the two types of disturbances lead to different processes. For the random disturbance, the detonation front evolves into a stable spinning detonation. For the symmetrical diagonal disturbance, the detonation front displays a diagonal pattern at an early stage, but this pattern is unstable. It breaks down after a short while and it finally evolves into a spinning detonation. The spinning detonation structure ultimately formed due to the two types of disturbances is the same. This means that spinning detonation is the most stable mode for the simulated narrow duct. Therefore, in a narrow duct, triggering a spinning detonation can be an effective way to produce a stable detonation as well as to speed up the deflagration to detonation transition process.Comment: 30 pages and 11 figure

Pan-Eurasian Experiment (PEEX): Towards a holistic understanding of the feedbacks and interactions in the land-Atmosphere-ocean-society continuum in the northern Eurasian region

The northern Eurasian regions and Arctic Ocean will very likely undergo substantial changes during the next decades. The Arctic-boreal natural environments play a crucial role in the global climate via albedo change, carbon sources and sinks as well as atmospheric aerosol production from biogenic volatile organic compounds. Furthermore, it is expected that global trade activities, demographic movement, and use of natural resources will be increasing in the Arctic regions. There is a need for a novel research approach, which not only identifies and tackles the relevant multi-disciplinary research questions, but also is able to make a holistic system analysis of the expected feedbacks. In this paper, we introduce the research agenda of the Pan-Eurasian Experiment (PEEX), a multi-scale, multi-disciplinary and international program started in 2012 (https://www.atm.helsinki.fi/peex/). PEEX sets a research approach by which large-scale research topics are investigated from a system perspective and which aims to fill the key gaps in our understanding of the feedbacks and interactions between the land-Atmosphere-Aquatic-society continuum in the northern Eurasian region. We introduce here the state of the art for the key topics in the PEEX research agenda and present the future prospects of the research, which we see relevant in this context