Оценка рентгенометрических показателей костей предплечья при травматической нестабильности дистального лучелоктевого сустава у детей

Background. At present, the literature describes in sufficient detail the use of various methods of X-ray examination of the bones of the forearm in the diagnosis of distal radioulnar joint instability (DRUJI), but there are no data on radiometric parameters for DRUJI of traumatic origin in children. Quantitative diagnostics becomes mandatory for determining the tactics of treating DRUJI of traumatic origin in children. The purpose of study to analyze the radiometric parameters of the distal forearm in case of DRUJI of traumatic origin in children to plan the method of surgical treatment. Мethods. The paper presents an analysis of the results of X-ray examination of 23 children with instability of the distal radioulnar joint of traumatic origin aged 9 to 17 years (mean age 14.212.5 years) the main group. For comparison, radiographs of the contralateral forearms of the same patients were analyzed the comparison group (23 children), and radiographs of the forearm of 69 pediatric patients without signs of DRUJI (control group). On radiographs in the anteroposterior and lateral projections, the following radiometric parameters were evaluated: radioulnar and volar angles, radioulnar index, radioulnar distance, and the difference between the radioulnar distances of both forearms. Results. In 19 patients of the main group, a positive variant of the radioulnar index with dislocation of the head of the ulna was revealed, while the indicators of the radioulnar and volar angle were characterized by variability in values. The average values of radiometric parameters of DRUJI in children without bone-traumatic changes of the forearm are comparable to normal values in adults. Conclusions. In children with DRUJI of traumatic origin, various changes were revealed radiometric indicators of the distal parts of the bones of the forearm, which depend on the type of forearm fracture. In a particular pediatric patient with DRUJI of traumatic origin, these indicators reflect the biomechanical features of the wrist joint, which must be taken into account when planning surgical intervention and predicting the recovery of the anatomy and function of the forearm.Актуальность. В настоящее время в литературе достаточно подробно описано применение различных методик рентгенологического исследования костей предплечья при диагностике нестабильности дистального лучелоктевого сустава (ДЛЛС), но отсутствуют сведения о рентгенометрических показателях при нестабильности ДЛЛС травматического генеза у детей. Квантитативная диагностика приобретает обязательный характер для определения тактики лечения нестабильности ДЛЛС травматического генеза у детей. Цель исследования проанализировать рентгенометрические показатели дистальных отделов костей предплечья при нестабильности ДЛЛС травматического генеза у детей для планирования хирургического лечения. Материал и методы. В работе представлен анализ результатов рентгенологического исследования 23 детей с нестабильностью ДЛЛС травматического генеза в возрасте от 9 до 17 лет (средний возраст 14,22,5 года) основная группа. Для сравнения анализировали рентгенограммы контралатеральных предплечий этих же пациентов группа сравнения (23 ребенка) и рентгенограммы костей предплечья 69 пациентов детского возраста без признаков нестабильности ДЛЛС (контрольная группа). На рентгенограммах в переднезадней и боковой проекциях оценивали следующие рентгенометрические показатели: лучелоктевой и волярный углы, лучелоктевой индекс, радиоульнарное расстояние и разницу между радиоульнарными расстояниями обоих предплечий. Результаты. У 19 пациентов с нестабильностью ДЛЛС травматического генеза был выявлен положительный вариант лучелоктевого индекса с вывихом головки локтевой кости, в то время как показатели лучелоктевого и волярного угла характеризовались вариабельностью значений. Средние рентгенометрические параметры ДЛЛС у детей без костно-травматических изменений костей предплечья сопоставимы с нормальными значениями у взрослых. Заключение. У детей с нестабильностью ДЛЛС травматического генеза выявлены различные изменения рентгенометрических показателей дистальных отделов костей предплечья, которые зависят от типа перелома. У конкретного пациента детского возраста с нестабильностью ДЛЛС травматического генеза эти показатели отражают биомеханические особенности кистевого сустава, что необходимо учитывать при планировании хирургического вмешательства и прогнозировании восстановления анатомии и функции предплечья

Weak localization, Aharonov–Bohm oscillations and decoherence in arrays of quantum dots

Combining scattering matrix theory with non-linear σ-model and Keldysh technique we develop a unified theoretical approach enabling one to non-perturbatively study the effect of electron–electron interactions on weak localization and Aharonov–Bohm oscillations in arbitrary arrays of quantum dots. Our model embraces weakly disordered conductors, strongly disordered conductors and (iii) metallic quantum dots. In all these cases at T→0 the electron decoherence time is found to saturate to a finite value determined by the universal formula which agrees quantitatively with numerous experimental results. Our analysis provides overwhelming evidence in favor of electron–electron interactions as a universal mechanism for zero temperature electron decoherence in disordered conductors

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We consider an integrable conformally invariant two dimensional model associated to the affine Kac-Moody algebra SL(3). It possesses four scalar fields and six Dirac spinors. The theory does not possesses a local Lagrangian since the spinor equations of motion present interaction terms which are bilinear in the spinors. There exists a submodel presenting an equivalence between a U(1) vector current and a topological current, which leads to a confinement of the spinors inside the solitons. We calculate the one-soliton and two-soliton solutions using a procedure which is a hybrid of the dressing and Hirota methods. The soliton masses and time delays due to the soliton interactions are also calculated. We give a computer program to calculate the soliton solutions.Comment: plain LaTeX, 37 page

Dual Isomonodromic Deformations and Moment Maps to Loop Algebras

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Oil pollution in the southeastern Baltic Sea by satellite remote sensing data in 2004-2015

The results of satellite monitoring of oil pollution in the Southeastern Baltic Sea in 2004-2015 are discussed in the paper. Interannual and seasonal variability of oil pollution is investigated. A steady decrease in total oil pollution was observed from 2004 to 2011. After a sharp increase of oil pollution in 2012, oil pollution level has established at 0.39 PI Index. Maximum of oil spills is observed in the spring and summer, which is probably due to favorable weather conditions for the detection of oil spills on radar images. According to the analysis of the shapes of the detected oil spills, it was concluded that the main polluters of the sea surface are vessels. No oil spills originated from the oil platform D-6 was detected in 2004-2015. Results of numerical experiments with the Seatrack Web oil spill model show that in the case of potential discharge of oil from the D-6 platform, oil will not reach the Curonian Spit beaches during 48 h after an accident

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Results of operational satellite monitoring of oil pollution of the sea surface together with in-situ measurements of the oil products concentration in the water column for the first time allowed to establish relation between the surface pollution originated from ships, and the general characteristics of spatial and temporal distribution of oil products in the water column in the Southeastern Baltic Sea. Areas with heightened concentrations of oil products in the surface and bottom layers were determined for the study area. The main directions of the contamination propagation are agreed with the main direction of annual mean transport of substances in the Gdansk Basin

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The key concept discussed in these lectures is the relation between the Hamiltonians of a quantum integrable system and the Casimir elements in the underlying hidden symmetry algebra. (In typical applications the latter is either the universal enveloping algebra of an affine Lie algebra, or its q-deformation.) A similar relation also holds in the classical case. We discuss different guises of this very important relation and its implication for the description of the spectrum and the eigenfunctions of the quantum system. Parallels between the classical and the quantum cases are thoroughly discussed.Comment: 59 pages, LaTeX2.09 with AMS symbols. Lectures at the CIMPA Winter School on Nonlinear Systems, Pondicherry, January 199

Landau gauge Jacobian and BRST symmetry

Copyright © 2005 Elsevier B.V. All rights reserved. Copyright © 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. Submitted to Cornell University’s online archive www.arXiv.org in 2005 by Alexander Kalloniatis. Post-print sourced from www.arxiv.org.We propose a generalisation of the Faddeev-Popov trick for Yang-Mills fields in the Landau gauge. The gauge-fixing is achieved as a genuine change of variables. In particular the Jacobian that appears is the modulus of the standard Faddeev-Popov determinant. We give a path integral representation of this in terms of auxiliary bosonic and Grassman fields extended beyond the usual set for standard Landau gauge BRST. The gauge-fixing Lagrangian density appearing in this context is local and enjoys a new extended BRST and anti-BRST symmetry though the gauge-fixing Lagrangian density in this case is not BRST exact.M. Ghiotti, A.C. Kalloniatis and A.G. Williamshttp://www.elsevier.com/wps/find/journaldescription.cws_home/505706/description#descriptio

Generalized Drinfeld-Sokolov Reductions and KdV Type Hierarchies

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