Study of the Reynolds Number Effect on the Process of Instability Transition Into the Turbulent Stage.

The results of the experimental study of the Reynolds number effect on the process of the Rayleigh-Taylor (R-T) instability transition into the turbulent stage are presented. The experimental liquid layer was accelerated by compressed gas. Solid particles were scattered on the layer free surface to specify the initial perturbations in some experiments. The process was recorded with the use of a high-speed motion picture camera. The following results were obtained in experiments: (1) Long-wave perturbation is developed at the interface at the Reynolds numbers Re < 104. If such perturbation growth is limited by a hard wall, the jet directed in gas is developed. If there is no such limitation, this perturbation is resolved into the short-wave ones with time, and their growth results in gas-liquid mixing. (2) Short-wave perturbations specified at the interface significantly reduce the Reynolds number Re for instability to pass into the turbulent mixing stage.

[Clinical evaluation of Parkinson's disease progression]. / Klinicheskaia otsenka progressirovaniia bolezni Parkinsona.

Objective. We conducted a prospective study on the dynamics of clinical progression of motor and non-motor impairments in PD from 2009 to 2012. Material and methods. We examined 136 patients with Parkinson's disease, 77 men and 59 women, mean age 63.2±10.4 years, disease duration 7.5±3.8 years, including 50 (36.8%) patients at the mild stage of disease, 67 (49.3%) patients at the moderate stage and 19 (13.9%) patients at the advanced stage. Evaluation of progression was carried out annually using part III UPDRS: an annual increase of 9 scores or more indicated the fast progression; from 5 to 8 scores - moderate progression; up to 4 scores - slow progression. Results. Eighty-five patients (62.5%) had slow progression, 39 patients (27.1%) had moderate progression and 12 patients (10.4%) had fast progression. Conclusion. Older age, severity of axial movement disorders, cognitive impairment and motor fluctuations, orthostatic hypotension and psychotic disorders (hallucinations) predicted the fast progression.

[Current state, challenges and prospects for the development of the Russian urological service].

The present study was dedicated to the analysis of the incidence, prevalence and mortality from diseases of the urogenital system. The data on the effectiveness of the hospital bed usage, the patient profile at hospital, the treatment timing and outcomes, surgical activities in urological hospitals, the state of staff assistance in urological service, the efficacy of usage of working time of urologist and human resource of Russian urological service were analyzed. Data analysis revealed a number of issues of administrative and legal nature, which cause modest efficiency of activity of urological service. The ways for solutions of these problems are presented.

[Akatinol memantine in the therapy of cognitive disorders in Parkinson's disease].

Thirty-eight patients, 20 male, 18 female, mean age 61.8+/-7.7 years, illness duration 8.4+/-1.3 years, have been studied. The degree of severity of Parkinson's disease (PD) according to the Hoehn and Yahr scale was 2.6+/-0.4. Mild cognitive impairment was observed in all cases. Akatinol memantine was prescribed to patients, who have been receiving levodopa, in the following dosages: the first week--5mg daily, the second week--10 mg daily and from the third week--20 mg in fractional dosages. Treatment duration was 6 months. The patient's state before and after treatment was assessed clinically and with several scales measuring cognitive and motor functions. It was shown that akatinol memantine not only reduced disorders typical for PD (hypokinesia, rigidity, tremor) and increased the daily activity of patients but significantly improved the indices of logic and visual memory, speech functions and thinking.

[A comparative study of efficacy of dopamine receptors agonists and catechol-O-methyltransferase in the treatment of late stages of Parkinson's disease]. / Sravnitel'noe issledovanie éffektivnosti agonistov dofaminovykh retseptorov i ingibitorov katekhol-O-metiltransferazy v lechenii pozdnikh stadii bolezni Parkinsona.

Dopamine receptors agonists and catechol-O-methyltransferase (COMT) inhibitors are the novel classes of the drugs for Parkinson's disease (PD) treatment in both early and late stages. In the latter one, there is an increase of substantia nigra neurons degeneration, striatum denervation, changes of dopamine receptors state, dysregulation of Levadopa uptake, dopamine synthesis and storage, decrease of dopamine receptors density in striatum that results in clinical picture alteration and development of pharmaco-therapeutic side-effects, as well as motor fluctuations and drug diskinesias. The use of dopamine receptors agonists and COMT inhibitors at the late PD stages in combination with other antiparkinsonian medications allows improving pharmaco-therapeutic efficacy, along with patient's daily activity and quality of life.

Operation planning of correction osteotomies in 3D.

This paper discusses an operation planning system for correction osteotomies. It is based on 3D data obtained from CT/MR of the bone and it allows to perform a 3D planning. The physician can individually determine anatomical landmarks for measuring geometric parameters of the bone like length, angle and torsion angle. In a virtual scene he or she can set a single cut or can remove/insert a wedge, dissecting the bones. The bone parts can be rearranged in 3D space. Optimization routines allow that the physician only defines the position of the cut, the orientation of the cut plane, the rearrangement of the bone and the optimization for the maximal overlap of the cortical bone can be processed automatically. The system is currently in use at the Trauma department at the University of Ulm. A case study shows the results by applying this system.

Computer assisted treatment of pelvis fractures.

The presented approach is the realization of a minimal invasive treatment of pelvis fractures using the computer aided surgery (CAS). Main problem of tracking of major bone fragments after reposition is solved by implementing of 3D ultrasound to obtain intraoperative bone surfaces. Preoperative and intraoperative data sets are matched. Major fragments are tracked. The real time navigation is possible.

Computer simulation of osteotomy correction.

This paper describes a novel approach to correct osteotomy deformities of long bones using virtual reality and image processing techniques on personal computers. The discussed method allows to simulate osteotomy corrections by implementing a single cut and a rearrangement of the dissected bone parts. It allows the surgeon to directly control the pre-operative situation and the post-operative result of the simulation by comparing bone-length, angles, and torsion of the bone. In addition, he or she obtains the coordinates and angles of the planned cut relative to anatomical landmarks.