Higher-dimensional solitons and black holes with a non-minimally coupled scalar field

We study higher-dimensional soliton and hairy black hole solutions of the Einstein equations non-minimally coupled to a scalar field. The scalar field has no self-interaction potential but a cosmological constant is included. Non-trivial solutions exist only when the cosmological constant is negative and the constant governing the coupling of the scalar field to the Ricci scalar curvature is positive. At least some of these solutions are stable when this coupling constant is not too large.Comment: 17 pages, revtex4, 21 figures, minor changes to match published versio

The contribution of CYP2C gene subfamily involved in epoxygenase pathway of arachidonic acids metabolism to hypertension susceptibility in Russian population

The present study was designed to investigate whether common single-nucleotide polymorphisms (SNP) of CYP2C gene subfamily such as CYP2C8 (rs7909236 and rs1934953), CYP2C9 (rs9332242), and CYP2C19 (rs4244285) are associated with susceptibility to EH in Russian populatio

Black holes in scalar-tensor gravity

Hawking has proven that black holes which are stationary as the endpoint of gravitational collapse in Brans--Dicke theory (without a potential) are no different than in general relativity. We extend this proof to the much more general class of scalar-tensor and f(R) gravity theories, without assuming any symmetries apart from stationarity.Comment: v1: 4 pages; v2: typos corrected, published versio

Journal benchmarking for strategic publication management and for improving journal positioning in the world ranking systems

Is studied Elaborating policies and strategies for the promotion of scientific journals in the world ranking systems. It is suggested to build up a journal scoreboard, which is a matrix of journal indicators, distributed for different journalsyesBelgorod State Universit

THE ROLE OF SIGNALING MOLECULES IN THE DEVELOPMENT OF CHEILITIS CAUSED BY UV IRRADIATION AND SEBORRHEIC ECZEMA

The subject of the study is the establishment of the role of signaling molecules in the development of cheilitis in patients after sensitizing effects on the skin of the red border of the lips of various factors. For this purpose, blood levels of substance P, histamine, tumor necrosis factor-alpha (TNFα) in patients with actinic cheilitis and cheilitis developed against seborrheic eczema were studied. The reliability of the results of clinical and laboratory studies was established by methods of modern statistical processing. It was found that the development of clinical manifestations of lesions of the red border of the lips with sensitizing effects (UV rays and seborrheic process) is reliably associated with a synergistic increase in blood levels of signal molecules of different classes (not opioid neuropeptide, biogenic amine, pro-inflammatory cytokine). The obtained results substantiate new approaches to drawing up plans for examination, treatment and prevention of patients with development of cheilitis after sensitizing effects of UV rays and against seborrheic eczema.Key words: cheilitis (actinic and against the background of seborrheic eczema), signaling molecules (substance P, histamine, TNFα).кандидат медицинских наук, Бочарова В.В., доктор медицинских наук, профессор, Лебедюк М.Н., *доктор медицинских наук, профессор, Бочаров В.А., **доктор медицинских наук, доцент, Куц Л.В. Роль сигнальных молекул в развитии хейлитов, вызванных уф-облучением и себорейной экземой/ Одесский национальный медицинский университет, Украина, Одесса; *Медицинский институт Международного гуманитарного университета, Украина, Одесса; **Медицинский институт Сумского государственного университета, Украина, СумыПредметом исследования является установление роли сигнальных молекул в развитии хейлитов у больных после сенсибилизирующих воздействий на кожу красной каймы губ различных факторов. С этой целью были изучены уровни содержания в крови субстанции Р, гистамина, фактора некроза опухоли-альфа (TNFα) у больных с актиническим хейлитом и хейлитом, развившемся на фоне себорейной экземы. Достоверность результатов клинических и лабораторных исследований устанавливалась методами современной статистической обработки. Выявлено, что развитие клинических проявлений поражения красной каймы губ при сенсибилизирующих воздействиях (УФ-лучей и при себорейном процессе) достоверно связано с синергичным повышением уровней в крови сигнальных молекул разных классов (неопиоидного нейропептида, биогенного амина, провоспалительного цитокина). Полученные результаты обосновывают новые подходы к составлению планов обследования, лечения и профилактики больных с развитием хейлитов после сенсибилизирующих воздействий УФ-лучей и на фоне себорейной экземы.Ключевые слова: хейлиты (актинический и на фоне себорейной экземы), сигнальные молекулы (субстанция Р, гистамин, TNFα).

Dressing a black hole with non-minimally coupled scalar field hair

We investigate the possibility of dressing a four-dimensional black hole with classical scalar field hair which is non-minimally coupled to the space-time curvature. Our model includes a cosmological constant but no self-interaction potential for the scalar field. We are able to rule out black hole hair except when the cosmological constant is negative and the constant governing the coupling to the Ricci scalar curvature is positive. In this case, non-trivial hairy black hole solutions exist, at least some of which are linearly stable. However, when the coupling constant becomes too large, the black hole hair becomes unstable.Comment: 17 pages, 7 figures, uses iopart.cls. Minor changes, accepted for publication in Classical and Quantum Gravit

Instability of a four-dimensional de Sitter black hole with a conformally coupled scalar field

We study the stability of new neutral and electrically charged four-dimensional black hole solutions of Einstein's equations with a positive cosmological constant and conformally coupled scalar field. The neutral black holes are always unstable. The charged black holes are also shown analytically to be unstable for the vast majority of the parameter space of solutions, and we argue using numerical techniques that the configurations corresponding to the remainder of the parameter space are also unstable.Comment: revtex4, 8 pages, 4 figures, minor changes, accepted for publication in Phys. Rev.

Thermodynamics of black holes with an infinite effective area of a horizon

In some kinds of classical dilaton theory there exist black holes with (i) infinite horizon area $A$ or infinite $F$ (the coefficient at curvature in Lagrangian) and (ii) zero Hawking temperature $T_{H}$. For a generic static black hole, without an assumption about spherical symmetry, we show that infinite $A$ is compatible with a regularity of geometry in the case $T_{H}=0$ only. We also point out that infinite $T_{H}$ is incompatible with the regularity of a horizon of a generic static black hole, both for finite or infinite $A$. Direct application of the standard Euclidean approach in the case of an infinite ''effective'' area of the horizon $A_{eff}=AF$ leads to inconsistencies in the variational principle and gives for a black hole entropy $S$ an indefinite expression, formally proportional to $T_{H}A_{eff}$. We show that treating a horizon as an additional boundary (that is, adding to the action some terms calculated on the horizon) may restore self-consistency of the variational procedure, if $F$ near the horizon grows not too rapidly. We apply this approach to Brans-Dicke black holes and obtain the same answer S=0 as for ''usual'' (for example, Reissner-Nordstr\"{o}m) extreme classical black holes. We also consider the exact solution for a conformal coupling, when $A$ is finite but $F$ diverges and find that in the latter case both the standard and modified approach give rise to an infinite action. Thus, this solution represents a rare exception of a black hole without nontrivial thermal properties.Comment: 24 pages. Accepted for publication in Class. Quant. Gra

Instability of three dimensional conformally dressed black hole

The three dimensional black hole solution of Einstein equations with negative cosmological constant coupled to a conformal scalar field is proved to be unstable against linear circularly symmetric perturbations.Comment: 5 pages, REVTe