Biomechanical grounding of the transalveolar osteosynthesis of еdentulous мandible fractures

The purpose of the work is improvement of the effectiveness of the mandibular fractures treatment in patients with partial or complete adentia by developing and experimentally testing transalveolar osteosynthesis technique. An experimental study was carried out by 3D computer simulation modeling by the final element analysis to assess the efficiency of mandibular fractures fixation at partial or complete adentia using the Ш-shaped plate, which we developed for the transalveolar osteosynthesis method. Calculations of the immobilized fractures for static (own weight) and dynamic (functional) loads were performed according to the author's method, taking into account pronounced resorptive processes in the bone from the beginning of the reparative reaction to assess the rigidity of fragments fixation during the entire period of the fractures healing. Under the conditions of the same three-dimensional model of the mandible, calculations were performed when the fracture was fixed with ordinary linear titanium osseous plates. It is proved that at functional load the new plate provides a compression effect in the fractures region, as evidenced by the negative displacements in the final elements of the mental region according to the results of design load combination 2- 3. The maximum efforts in the screws of the calculation model with a conventional bone plate were 136.955 N, which is almost ten times more than on the model with a Ш-shaped titanium retainer (12.656 N)

Decay of the Sinai Well in D dimensions

We study the decay law of the Sinai Well in $D$ dimensions and relate the behavior of the decay law to internal distributions that characterize the dynamics of the system. We show that the long time tail of the decay is algebraic ($1/t$), irrespective of the dimension $D$.Comment: 14 pages, Figures available under request. Revtex. Submitted to Phys. Rev. E.,e-mail: [email protected]

Ultra-high energy cosmic ray investigations by means of EAS muon density measurements

A new approach to investigations of ultra-high energy cosmic rays based on the ground-level measurements of the spectra of local density of EAS muons at various zenith angles is considered. Basic features of the local muon density phenomenology are illustrated using a simple semi-analytical model. It is shown that muon density spectra are sensitive to the spectrum slope, primary composition, and to the features of hadronic interaction. New experimental data on muon bundles at zenith angles from 30 degrees to horizon obtained with the coordinate detector DECOR are compared with CORSIKA-based simulations. It is found that measurements of muon density spectra in inclined EAS give possibility to study characteristics of primary cosmic ray flux in a very wide energy range from 10^15 to 10^19 eV.Comment: 7 pages, 7 figures. Presented at CRIS-2006, Catania, Italy, May 29 - June 2, 2006. Accepted for publication in Nucl. Phys. B (Proc. Suppl.

New technique and results of cosmic ray investigations in the energy interval 1015–1019 eV

New technique of EAS investigations based on the measurements of local muon density spectra (LMDS) is developed. Application of this method to investigations of inclined EAS allows exploration of CR energy interval from 10 15 to 10 19 eV by means of a relatively small detector with area ∼100m 2 due to very strong dependence of EAS muon density on zenith angle. During 2002-2007, long-term NEVOD- DECOR experiment (about 20,000h live time) was conducted, and more than two million muon bundles in zenith angle interval 30-88 degrees were registered. Comparison of experimental data with results of CORSIKA-based simulations showed that the new method is sensitive to all main peculiarities of CR energy spectrum: the knee, increase of the energy spectrum slope with energy, the second knee. But the observed progressive excess of muon bundles with the increase of primary CR energy in comparison with simulations (even for pure iron composition) can indicate the appearance of new processes of muon generation. In this case, for correct investigations of EAS, the experimental arrays must be supplemented by detectors which can measure or evaluate the energy of muons

Magnetic properties and structure of Nd-Fe-B melt-spun alloys for isotropic bonded magnets

The phase evolution and magnetic properties of both melt-spun NdₓFe₉₈.₉₋ₓB₁.₁ x = 10-39 mass % ribbons and isotropic bonded magnets have been investigated. A high coercivity and remanence has been shown to be attainable even in the as-spun state with Nd in the range of x = 28-30 mass % without heat treatment. The influence of heat treatment in the 530 to 730° C range on magnetic properties of melt-spun ribbons has been studied. A well-expressed effect of Nd concentration on the lattice volume of Nd₂Fe₁₄B (P4₂/mnm) phase and volume fraction of secondary phases has been revealed. It was shown that exchange-coupling effect plays important role in the hard magnetic properties of the alloys with low Nd content, but melt-spun alloys with high remanence along are not sufficient to guarantee high magnetic performance

New technique and results of cosmic ray investigations in the energy interval 10

New technique of EAS investigations based on the measurements of local muon density spectra (LMDS) is developed. Application of this method to investigations of inclined EAS allows exploration of CR energy interval from 1015 to 1019eV by means of a relatively small detector with area ∼100m2 due to very strong dependence of EAS muon density on zenith angle. During 2002–2007, long-term NEVOD-DECOR experiment (about 20,000 h live time) was conducted, and more than two million muon bundles in zenith angle interval 30–88 degrees were registered. Comparison of experimental data with results of CORSIKA-based simulations showed that the new method is sensitive to all main peculiarities of CR energy spectrum: the knee, increase of the energy spectrum slope with energy, the second knee. But the observed progressive excess of muon bundles with the increase of primary CR energy in comparison with simulations (even for pure iron composition) can indicate the appearance of new processes of muon generation. In this case, for correct investigations of EAS, the experimental arrays must be supplemented by detectors which can measure or evaluate the energy of muons

Optical properties and charge transfer effects in single-walled carbon nanotubes filled with functionalized adamantane molecules

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