463 research outputs found
Generalized Neighbor-Interaction Models Induced by Nonlinear Lattices
It is shown that the tight-binding approximation of the nonlinear
Schr\"odinger equation with a periodic linear potential and periodic in space
nonlinearity coefficient gives rise to a number of nonlinear lattices with
complex, both linear and nonlinear, neighbor interactions. The obtained
lattices present non-standard possibilities, among which we mention a
quasi-linear regime, where the pulse dynamics obeys essentially the linear
Schr{\"o}dinger equation. We analyze the properties of such models both in
connection with their modulational stability, as well as in regard to the
existence and stability of their localized solitary wave solutions
Controlled transport of matter waves in two-dimensional optical lattices
We propose a method for achieving dynamically controllable transport of
highly mobile matter-wave solitons in a driven two-dimensional optical lattice.
Our numerical analysis based on the mean-field model and the theory based on
the time-averaging approach, demonstrate that a fast time-periodic rocking of
the two-dimensional optical lattice enables efficient stabilization and
manipulation of spatially localized matter wavepackets via induced
reconfigurable mobility channels.Comment: 4 pages, 4 figure
Features of the implementation of information functions in linear indiction machine with opposite direction travelling magnetic field
The article deals with problems and prospects of linear induction machines with the primary, establishing the opposite direction travelling magnetic field. Such type of electrical machines primary windings structure is described.В статье рассмотрены проблемы и перспективы применения линейных индукционных машин с индуктором, создающим встречнобегущие магнитные поля. Приведены рекомендации по выбору структуры обмоток таких машин
Possibilities of induction heating installations based on three-phase linear inductors
The features of induction heating installations in a traveling magnetic field are considered. The expediency of using double-purpose linear induction machines and the prospects of using linear inductors creating opposite direction traveling magnetic fields are shown
SPECIFIC FEATURES OF SYSTEM INFLAMMATORY RESPONSE SYNDROME AND NUTRITIONAL STATUS IN PULMONARY TUBERCULOSIS PATIENTS WITH CONCURRENT TYPE 1 AND 2 DIABETES
45 pulmonary tuberculosis patients with concurrent type 1 diabetes, 69 pulmonary tuberculosis patients with concurrent type 2 diabetes and 131 pulmonary tuberculosis patients without diabetes (control group) were examined. The intensity of the system inflammatory response syndrome was evaluated by the markers of the acute inflammation phase – blood levels of C-reactive protein (CRP), serum amyloid A (SAA), α1 -antitrypsin (α1 -АТ), haptoglobin, and fibrinogen. Nutritional status was assessed by body mass index (BMI) and concentration of total protein (TP), albumin (A), and transthyretin (TTR). It was found out that in new progressing forms in pulmonary tuberculosis patients with concurrent diabetes the mobilisation of acute phase proteins responsible for early anti-infection protection (CRP, SAA) was less expressed compared to the patients without concurrent diabetes. On the contrary in torpent forms of the disease CRP and SAA were much higher in those with concurrent conditions compared to the patients without concurrent diabetes. The reaction of acute phase proteins in new cases and infiltrate and pneumonic forms of the disease was more severe in those with concurrent type 1 diabetes and more moderate and slow in case of type 2 diabetes. Nutritional status in the patients with concurrent conditions differed greatly from patients in the control group. With no concurrent diabetes all signs of nutritional deficiency (low BMI, A and TTR) promoted the severe course of the disease. TP remained within normal limits. Patients with concurrent diabetes demonstrated reduction TP and TTR, but BMI and A remained normal in case of type 1 diabetes and increased in type 2 diabetes. Ratio of albumins/globulins (A/G) went down in the control group but tended to increase in case of concurrent diabetes. According to correlation analysis the reduction of TP in the patients with concurrent condition was not due to A but globulins. Shifts fundamentally different for patients with concurrent diabetes and those without concurrent diabetes (increase of BMI, A, A/G) were much greater expressed in type 2 diabetes and manifestations of protein-energy deficiency (decrease of TP and TTR) were more intensive in type 1 diabetes
Modulational and Parametric Instabilities of the Discrete Nonlinear Schr\"odinger Equation
We examine the modulational and parametric instabilities arising in a
non-autonomous, discrete nonlinear Schr{\"o}dinger equation setting. The
principal motivation for our study stems from the dynamics of Bose-Einstein
condensates trapped in a deep optical lattice. We find that under periodic
variations of the heights of the interwell barriers (or equivalently of the
scattering length), additionally to the modulational instability, a window of
parametric instability becomes available to the system. We explore this
instability through multiple-scale analysis and identify it numerically. Its
principal dynamical characteristic is that, typically, it develops over much
larger times than the modulational instability, a feature that is qualitatively
justified by comparison of the corresponding instability growth rates
Endothelial Dysfunction in Diabetes Mellitus: Possible Involvement of Endoplasmic Reticulum Stress?
The vascular complications of diabetes mellitus impose a huge burden on the management of this disease. The higher incidence of cardiovascular complications and the unfavorable prognosis among diabetic individuals who develop such complications have been correlated to the hyperglycemia-induced oxidative stress and associated endothelial dysfunction. Although antioxidants may be considered as effective therapeutic agents to relieve oxidative stress and protect the endothelium, recent clinical trials involving these agents have shown limited therapeutic efficacy in this regard. In the recent past experimental evidence suggest that endoplasmic reticulum (ER) stress in the endothelial cells might be an important contributor to diabetes-related vascular complications. The current paper contemplates the possibility of the involvement of ER stress in endothelial dysfunction and diabetes-associated vascular complications
Inheritance of juvenile resistance to powdery mildew in barley accessions from Ethiopia
Background. Barley (Hordeum vulgare L.) is one of the key food crops, ranking fourth in the world in terms of sown area and production among cereals. Often, one of the main factors that reduces yield and product quality is the spread of fungal pathogens in commercial crops. Powdery mildew (causative agent: Blumeria graminis (DC.) Golovin ex Speer f. sp. hordei Marchal) is considered one of the most common and harmful among barley diseases. Plant resistance to B. graminis limits the spread of the disease, and the development of resistant cultivars prevents a decrease in plant productivity. The specificity of the host–pathogen relationship and the loss of efficiency in many genes determine the need for a continuous study of previously unexplored local barley forms and a search for new, most effective resistance genes.Materials and methods. The genetic control of juvenile resistance to B. graminis was studied in 14 accessions of spring barley from the Ethiopian (Abyssinian) center of crop origin. The natural population of the pathogen served as infectious material for infecting barley. The intensity and nature of sporulation as well as the qualitative reactions of plant tissues in response to the penetration of the fungus (necrosis and chlorosis) were accepted as indicators of resistance in the accessions. Powdery mildew resistance was assessed under laboratory and field conditions. The genetic control of the resistance trait was studied using the method of hybridological analysis followed by statistical processing.Results and conclusions. Barleys from the Ethiopian center of morphogenesis are characterized by great genetic diversity. Studying the inheritance of juvenile resistance to powdery mildew made it possible to ascertain the monogenic control of the trait in all studied forms. Ten barley accessions with one effective recessive resistance allele and four with the dominant control of the trait may be recommended for immunity-targeted breeding
Modulational instability in cigar shaped Bose-Einstein condensates in optical lattices
A self consistent theory of a cigar shaped Bose-Einstein condensate (BEC)
periodically modulated by a laser beam is presented. We show, both
theoretically and numerically, that modulational instability/stability is the
mechanism by which wavefunctions of soliton type can be generated in cigar
shaped BEC subject to a 1D optical lattice. The theory explains why bright
solitons can exist in BEC with positive scattering length and why condensate
with negative scattering length can be stable and give rise to dark solitary
pulses.Comment: Submitted, 4 pages, 3 figures. Revised versio
- …