Interlayer Exchange Coupling in (Ga,Mn)As-based Superlattices

The interlayer coupling between (Ga,Mn)As ferromagnetic layers in all-semiconductor superlattices is studied theoretically within a tight-binding model, which takes into account the crystal, band and magnetic structure of the constituent superlattice components. It is shown that the mechanism originally introduced to describe the spin correlations in antiferromagnetic EuTe/PbTe superlattices, explains the experimental results observed in ferromagnetic semiconductor structures, i.e., both the antiferromagnetic coupling between ferromagnetic layers in IV-VI (EuS/PbS and EuS/YbSe) superlattices as well as the ferromagnetic interlayer coupling in III-V ((Ga,Mn)As/GaAs) multilayer structures. The model allows also to predict (Ga,Mn)As-based structures, in which an antiferromagnetic interlayer coupling could be expected.Comment: 4 pages, 3 figure

A genetic perspective on social insect castes: A synthetic review and empirical study

The process of caste differentiation is central to understanding insect sociality because it is castes that enable division of labor. Presumably selection favors colonies that can divide labor in response to environmental demands, and for many taxa genetic factors are an important part of this equation. In my thesis, I first provide a framework for understanding genetic and epigenetic effects on caste. From mostly ant, bee and termite examples, I make clear that genotype-caste associations can evolve in different and sometimes complex ways and can involve additive or non-additive genetic effects that, in turn, may arise directly from focal individuals or indirectly via their social partners. I use this framework to launch my empirical analysis of my own. In my second chapter, I test alternative hypotheses that describe how genes evolve under direct versus indirect selection. I predict that genes associated with reproductive castes will evolve mostly under direct selection and show patterns of nucleotide substitution that differ from those associated with non-reproductive helper castes and thus evolving under indirect selection. Using an RNA-Seq dataset for the Eastern subterranean termite, I found that caste-biased and un-biased genes evolve at similar rates, most consistent with purifying selection. I therefore did not detect an obvious pattern of molecular evolution that is diagnostic of indirect or \u27kin\u27 selection. I did discover other, more subtle patterns of nucleotide substitution that I discuss in the context of termite social biology

Характер эндотелиальной дисфункции при анкилозирующем спондилите

In this research we evaluated the nature of endothelial dysfunction and vascular adsorption-rheological properties of serum in patients with ankylosing spondylitis, determined its characteristics in the presence of angiopathy and established communication with the clinical and instrumental parameters of vascular disease and the state of immunity. The study included 79 patients aged 15 to 66 years, among whom there were 95% of men and 5% of women. Endothelial vessels dysfunction occurs in each second patient with ankylosing spondylitis, which in the presence of clinical and instrumental vascular pathology accompanied by an increase in serum concentration of cyclic guanosine monophosphate and even greater reduction in prostacyclinemia parameters. The severity of disorders of vascular endothelial function in these patients is associated with disease duration, activity of the pathological process, the lesion of the peripheral nervous system, the severity of spondylopathies and sacroiliitis. В работе проведена оценка характера эндотелиальной дисфункции сосудов и адсорбционнореологических свойств крови у больных анкилозирующим спондилитом, определены ее особенности при наличии ангиопатии, установлена связь с клинико-инструментальными показателями сосудистой патологии и состоянием иммунитета. Под наблюдением находились 79 больных в возрасте от 15 до 66 лет, среди которых были 95% мужчин и 5% женщин. Эндотелиальная дисфункция сосудов развивается у каждого второго больного анкилозирующим спондилитом, которая при наличии клинико-инструментальной сосудистой патологии сопровождается нарастанием в крови концентрации циклического гуанозинмонофосфата и еще большим уменьшением параметров простациклинемии. Степень выраженности нарушений эндотелиальной функции сосудов у таких больных связана с длительностью заболевания, активностью патологического процесса, поражением периферической нервной системы, выраженностью спондилопатии и сакроилеита

The concept “Family” in English phraseology

This article deals with understanding of the concept “Family” in the English culture and phraseology. The given examples demonstrate different types of family relationships as parents – children, spouses, and the relations within the family as parents love, unfaithfulness and so on

The concept “Family” in English phraseology

This article deals with understanding of the concept “Family” in the English culture and phraseology. The given examples demonstrate different types of family relationships as parents – children, spouses, and the relations within the family as parents love, unfaithfulness and so on

Disturbance of the muscoloskeletal system in juvenile ankylosing spondylitis and disease developed in the adulthood (involvement of spine and sacroiliac joints).

Background. Two forms of ankylosing spondylitis (AS) are distinguished: juvenile and adult, depending on debut age of the disease. The diagnosis of juvenile AS (JAS) is one of the most urgent problems in a pediatric rheumatology. The peculiarities of AS course that onsets in childhood and adulthood are manifested by differences in the nature of a spinal column disturbance. At the same time, the evolution of JAS in adulthood remains unexplored. The goals and objectives of research: to study clinical and X-ray symptoms of spondylopathy and sacroiliitis course, to assess their characteristics in the disease that onset in childhood and adulthood. Material and methods. 217 patients with AS (193 men and 24 women) with an average age of 38 years were examined. The fast-progressing course of the disease was detected in 21% of cases, moderate and high degree of activity – in 79% of cases, the ІІ-ІІІ stage in 82%, and polyarthritis – in 65%. JAS was detected in 16% of cases (all boys), among them the third stage occurred twice more likely than among the other patients. Results. The clinical and radiologic signs of spondylopathy and sacroiliitis are observed in 95% and 97% of the total number of AS cases, respectively, among all patients with JAS lumbago was detected 4,3 times more frequently, sciatic muscles hypotrophy – 7,8 times, "the string symptom" - 2,9 times", the calcification of the spinal cord - 2,3 times, whereas the prevalence of spinal column injury, the severity of cervico-spondylopathy and sacroiliitis among patients with the disease debut in the adulthood is significantly greater, and the involvement in the process of the lumbar and thoracic spine are detected correspondingly twice as often and by 19%, occurrence of dorsalgia is 4 times as often, the limitation of body lateral bendover by 59%, while there are ambiguous dispersion-correlation links with extraarticular (systemic) manifestations of the disease, and the high prevalence of a peripheral articular syndrome regarding spondylopathy in JAS is a negative prognosis sign, and for the remaining patients there are indices of the Lansbury index and the index of arthro­pathy progression. Conclusion: the onset of AS in adulthood is a risk factor for the severe course of spondylopathy

Does nitrate reductase play a key role in photoinduction of carotenoid synthesis in Neurospora crassa?

Does nitrate reductase play a key role in photoinduction of caroteniod synthesis in Neurospora crassa

Thermally activated decomposition of (Ga,Mn)As thin layer at medium temperature post growth annealing

The redistribution of Mn atoms in Ga1-xMnxAs layer during medium-temperature annealing, 250-450 oC, by Mn K-edge X-ray absorption fine structure (XAFS) recorded at ALBA facility, was studied. For this purpose Ga1-xMnxAs thin layer with x=0.01 was grown on AlAs buffer layer deposited on GaAs(100) substrate by molecular beam epitaxy (MBE) followed by annealing. The examined layer was detached from the substrate using a “lift-off” procedure in order to eliminate elastic scattering in XAFS spectra. Fourier transform analysis of experimentally obtained EXAFS spectra allowed to propose a model which describes a redistribution/diffusion of Mn atoms in the host matrix. Theoretical XANES spectra, simulated using multiple scattering formalism (FEFF code) with the support of density functional theory (WIEN2k code), qualitatively describe the features observed in the experimental fine structure