Симптоми на ЛОР органите при пациенти с гастроезофагеална рефлуксна болест (ГЕРБ)

Въведение: Гастроезофагеалната рефлуксна болест (ГЕРБ) се дефинира, като хронично възпаление на долната трета на хранопровода в резултат на връщане на част от стомашното съдържание (а понякога и гастродуоденален рефлукс) към хранопровода и/или в съседни органи (фаринкса, ларинкса, бронхите), което води до променлив спектър от езофагеални и/или извън езофагеални признаци и симптоми, свързани или не с тъканни лезии.Цел: Да се определи разпространението на някои симптоми в ЛОР органите при пациенти с гастро-езофагеална рефлуксна болест (ГЕРБ).Материал и методи: Извършено е проучване на 54 пациенти в продължение на 18 месеца. При всички пациенти са осъществени: стандартно изследване на ЛОР органи; изследвания на гастроинтестинален тракт: горна ендоскопия (по Лос Анджелиската класификация, 2003 г.), контрастна рентгенография на хранопровода и стомаха с Бариев сулфат; pH тест. Резултатите се обработиха в програмата SPSS, версия 10.0.Резултати: Пациентите с типични симптоми на гастроезофагеална рефлуксна болест бяха 48 (88%). При двадесет и седем болни се установиха промени в лигавицата на хранопровода – клас А – 27 (50%), клас Б – 17 (31.5%) и 10 (18.5%) – от класове C + D. При по-тежки степени на езофагити бяха диагностицирани по-изявени симптоми и промени в устната кухина.Заключение: Нашите резултати, както и на други автори потвърждават, че промените в ЛОР органите при болни с ГЕРБ зависят от степентта на възпалителните промени в хранопровода

A note on spin chain/string duality

Recently a significant progress in matching the anomalous dimensions of certain class of operators in N=4 SYM theory and rotating strings was made. The correspondence was established mainly using Bethe ansatz technique applied to the spin s Heisenberg model. In a recent paper Kruczenski (hep-th/0311203) suggested to solve the Heisenberg model by using of sigme model approach. In this paper we generalize the solutions obtained by Kruczenski and comment on the dual string theory. It turns out that our solutions are related to the so called Neumann-Rosochatius integrable system. We comment on the spin chain solutions and on the string/gauge theory correspondence.Comment: v.2 One reference added, typos corrected, 21 page

Solving advection equations by applying the crank-nicolson scheme combined with the richardson extrapolation

Advection equations appear often in large-scale mathematical models arising in many fields of science and engineering. The Crank-Nicolson scheme can successfully be used in the numerical treatment of such equations. The accuracy of the numerical solution can sometimes be increased substantially by applying the Richardson Extrapolation. Two theorems related to the accuracy of the calculations will be formulated and proved in this paper. The usefulness of the combination consisting of the Crank-Nicolson scheme and the Richardson Extrapolation will be illustrated by numerical examples. Copyright Zahari Zlatev et al

BASICS OF THEORETICAL APPROACHES OF TECHNOLOGICAL PROCESSES WITH REGULAR TOSSING OF THE GRANULAR MEDIUM

Vibration interaction is used for development of modern technological processes in which required quality of product is provided due to interaction of the granular medium with the vibrating surface. The paper is devoted to development of mathematical models and estimation criteria form of movement, taking into account the effect of unilateral constraints, in dynamic interactions of elements of vibration technological processes as applied to increase the reliability and quality of vibrational machines. The study is focused on the formation of theoretical ideas about the dynamic interactions of a solid body with the vibrating surface based on the development of mathematical models by introducing of additional external forces and elastic ties with unilateral contact, including mathematical models of gapless movement of the compounded solids. In terms of practical applications the task is to develop and to approve experimentally the opportunities of the measuring devices fixing the modes of continuous tossing. According to the research the generalized approach to problems of dynamic synthesis of vibration technology implemented in continuous tossing the introduction of additional forces is developed. The basis of the approach is the introduction of the concept of the function of the gap, allowing to justify the construction of forms of motion of material particles in accordance with certain criteria, reflecting the properties of the trajectories of motion of material particles in the interaction with the vibrating surface. The mathematical models to determine the conditions for the formation of dynamic reactions in the vibrational structure consisting of several interconnected elements, including the possibilities of their pre-pressing by elastic ties and power factors is offered. The measuring device fixing the modes of continuous tossing is developed and experimentally approved

Material microstructure effects in micro-endmilling of Cu99.9E

This article presents an investigation of the machining response of metallurgically and mechanically modified materials at the micro-scale. Tests were conducted that involved micro-milling slots in coarse-grained Cu99.9E with an average grain size of 30 µm and ultrafine-grained Cu99.9E with an average grain size of 200 nm, produced by equal channel angular pressing. A new method based on atomic force microscope measurements is proposed for assessing the effects of material homogeneity changes on the minimum chip thickness required for a robust micro-cutting process with a minimum surface roughness. The investigation has shown that by refining the material microstructure the minimum chip thickness can be reduced and a high surface finish can be obtained. Also, it was concluded that material homogeneity improvements lead to a reduction in surface roughness and surface defects in micro-cutting

Dynamics of superconducting nanowires shunted with an external resistor

We present the first study of superconducting nanowires shunted with an external resistor, geared towards understanding and controlling coherence and dissipation in nanowires. The dynamics is probed by measuring the evolution of the V-I characteristics and the distributions of switching and retrapping currents upon varying the shunt resistor and temperature. Theoretical analysis of the experiments indicates that as the value of the shunt resistance is decreased, the dynamics turns more coherent presumably due to stabilization of phase-slip centers in the wire and furthermore the switching current approaches the Bardeen's prediction for equilibrium depairing current. By a detailed comparison between theory and experimental, we make headway into identifying regimes in which the quasi-one-dimensional wire can effectively be described by a zero-dimensional circuit model analogous to the RCSJ (resistively and capacitively shunted Josephson junction) model of Stewart and McCumber. Besides its fundamental significance, our study has implications for a range of promising technological applications.Comment: 15 pages, 14 figure

On semiclassical calculation of three-point functions in AdS_5 \times T^(1,1)

Recently there has been progress on the computation of two- and three-point correlation functions with two "heavy" states via semiclassical methods. We extend this analysis to the case of AdS_5 \times T^(1,1), and examine the suggested procedure for the case of several simple string solutions. By making use of AdS/CFT duality, we derive the relevant correlation functions of operators belonging to the dual gauge theory.Comment: 18 pages, added referenc

Spiky strings and single trace operators in gauge theories

We consider single trace operators of the form O_{m_1 ... m_n} = tr D_+^{m_1} F ... D_+^{m_n} F which are common to all gauge theories. We argue that, when all m_i are equal and large, they have a dual description as strings with cusps, or spikes, one for each field F. In the case of N=4 SYM, we compute the energy as a function of angular momentum by finding the corresponding solutions in AdS_5 and compare with a 1-loop calculation of the anomalous dimension. As in the case of two spikes (twist two operators), there is agreement in the functional form but not in the coupling constant dependence. After that, we analyze the system in more detail and find an effective classical mechanics describing the motion of the spikes. In the appropriate limit, it is the same (up to the coupling constant dependence) as the coherent state description of linear combinations of the operators O_{m_1 ... m_n} such that all m_i are equal on average. This agreement provides a map between the operators in the boundary and the position of the spikes in the bulk. We further suggest that moving the spikes in other directions should describe operators with derivatives other than D_+ indicating that these ideas are quite generic and should help in unraveling the string description of the large-N limit of gauge theories.Comment: 23 pages, 5 figures. v2: References and comments adde