Antagonistic and plant growth promoting properties of actinomycetes from rhizosphere Deschampsia antarctica È. Desv. (Galindez Island, Antarctica)

Aim. The isolation of actinomycetes from Deschampsia antarctica É. Desv. (Galindez Island, Antarctica) rhisosphere and determine their ability to produce compounds with antimicrobial and plant growth promotional properties.Мета. Виділення актиноміцетів з ризосфери Deschampsia antarctica É. Desv. популяцій антарктичного острова Галіндез, оцінка їхньої здатності пригнічувати фітопатогенні мікроорганізми і продукувати фітостимулювальні сполуки

Моделирование связи «структура-свойство» органических соединений на основе базисных подграфов молекулярных графов.

New method for the constructing the quantitative structure-property relationships of organic compounds represented as labeled graphs is suggested. It is based on some results of spectral graph theory. A number of examples of application of this method is givenПредложен новый метод построения количественных соотношений, связывающих структуру и свойства органических соединений, представленных мечеными графами. Метод основан на некоторых результатах спектральной теории графов. Приведены примеры применения метода

Cerebellar anaplastic astrocytoma in adult patients: 15 consecutive cases from a single institution and literature review

Adult cerebellar anaplastic astrocytomas (cAA) are rare entities and their clinical and genetic appearances are still ill defined. Previously, malignant gliomas of the cerebellum were combined and reviewed together (cAA and cerebellar glioblastomas (cGB), that could have possibly affected overall survival (OS) and progression-free survival (PFS). We present characteristics of 15 adult patients with cAA and compared them to a series of 45 patients with a supratentorial AA (sAA) in order to elicit the effect of tumor location on OS and PFS. The mean age at cAA diagnosis was 39.3 years (range 19–72). A history of neurofibromatosis type I was noted in 1 patient (6.7%). An IDH-1 mutation was identified in 6/15 cases and a methylated MGMT promoter in 5/15 cases. Patients in study and control groups were matched in age, sex and IDH-1 mutation status. Patients in a study group tended to present with longer overall survival (50 vs. 36.5 months), but the difference did not reach statistical significance. In both cAA and supratentorial AA groups presence of the IDH-1 mutation remains a positive predictor for the prolonged survival. The present study suggests that adult cAA constitute a group of gliomas with relatively higher rate of IDH-1 mutations and prognosis similar to supratentorial AA. The present study is the first to systematically compare cAA and supratentorial AA with respect to their genetic characteristics and suggests that both groups show a similar survival prognosis

Predicting and Understanding Cancer Response to Treatment

Contains fulltext : 196925.pdf (publisher's version ) (Open Access

Magnetic susceptibility of YbRh2Si2 and YbIr2Si2 on the basis of a localized 4f electron approach

We consider the local properties of the Yb3+ ion in the crystal electric field in the Kondo lattice compounds YbRh2Si2 and YbIr2Si2. On this basis we have calculated the magnetic susceptibility taking into account the Kondo interaction in the simplest molecular field approximation. The resulting Curie-Weiss law and Van Vleck susceptibilities could be excellently fitted to experimental results in a wide temperature interval where thermodynamic and transport properties show non-Fermi-liquid behaviour for these materials.Comment: 12 pages, 4 figures, 4 table

Can contagious itch be affected by positive and negative suggestions?

Contagious itch can be evoked by observing people scratching. Verbal suggestions about to-be-received itch can influence itch intensity, as shown by placebo research, but it is unknown whether this extends to contagious itch. The current study aimed to replicate prior findings that listening to scratching and rubbing sounds elicits contagious itch, and to investigate whether suggestions can modulate this process. Healthy participants (n= 140) received positive or negative suggestions about itch in response to the sounds (aimed to decrease or increase expected itch, respectively), or no specific suggestions as a control. Participants listened to a number of audio fragments with scratching and rubbing sounds. The amount of expected itch as well as itch sensation after each audio fragment were measured by self-report. Suggestions had no effect on the expected itch. Both rubbing and scratching sounds significantly elicited itch in all groups. Scratching sounds induced more itch than rubbing sounds exclusively in the control group. These findings indicate that short suggestions might be not effective enough to modify the expectations of people regarding contagious itch. Furthermore, suggestions modulate contagious itch to some degree, but not in the hypothesized direction. Potential similarities and differences in the neurobiological mechanisms of contagious itch and nocebo effects are discussed

Моделирование связи между структурой и температурой плавления производных пиразолона: топологический подход

In the framework of the statistical approach the non-linear «structure - melting point» model for pyrazolone derivatives is constructed. Number of topological parameters calculated from the structural formula was used for the quantitative description of the molecular structure. The results of calculation of the melting points for a series of compounds of considered class are reported.В рамках статистического подхода построена нелинейная модель связи «структура - температура плавления» для производных пиразолона. Для количественного описания молекулярной струк-туры использован ряд топологических параметров, вычисляемых непосредственно из струк-турных формул молекул. Приведены результаты использования построенной модели для расчета температур плавления соединений рассматриваемого класса, не включенных в исходную выборку

ГИПЕРГРАФОВЫЕ МОДЕЛИ МОЛЕКУЛ УГЛЕВОДОРОДОВ И ИХ ПРИМЕНЕНИЕ В КОМПЬЮТЕРНОЙ ХИМИИ

A new form of representing the structures of saturated hydrocarbons as hypergraphs of special kind is suggested. A vertex of such hypergraph corresponds to a carbon atom in the molecule, and a hyperedge is defined as a set of vertices corresponding to some fixed carbon atom and all carbon atoms bounded with it. The comparison of the traditional graph model and the suggested hypergraph model using definite quantitative criteria related to some tasks of computer chemistry is fulfilled. For these investigations some set of hydrocarbons presented by their structural formulae is used. In particular, different invariants and codes of graphs and hypergraphs were calculated and their degeneration on the given set of structures was studied and compared. Two models were also compared by the ability of some local vertex invariants derived from them to distinguish topologically nonequivalent vertices in the traditional graph model. It is shown that in all cases in accordance with the used criteria the hypergraph model is better than the graph model. Besides, a number of structure–property relationships on the base of invariants of the suggested hypergraphs was obtainedПредложен новый способ представления структур насыщенных углеводородов в виде гипер-графов специальной конструкции. Проведено сравнение традиционной графовой модели и предложенной гиперграфовой модели. Для этой цели введен ряд количественных критериев, характеризующих эффективность применения той или иной модели при решении опре-деленных задач компьютерной химии. Для исследований использована некоторая выборка угле-водородов, представленных своими структурными формулами. Показано, что по всем рассмотренным критериям гиперграфовая модель превосходит графовую. Кроме того, на основе инвариантов предложенных гиперграфов для соединений заданной выборки построен ряд корреляций «структура-свойство»

Crystal electric field parameters for Yb3+ ion in YbRh2Si2

The tetragonal crystal electric field parameters for Yb3+ ion in YbRh2Si2 are determined from the analysis of the literature data on angle-resolved photoemission, inelastic neutron scattering and electron paramagnetic resonance.Comment: 8 pages, 3 figures, 4 table

Why could Electron Spin Resonance be observed in a heavy fermion Kondo lattice?

We develop a theoretical basis for understanding the spin relaxation processes in Kondo lattice systems with heavy fermions as experimentally observed by electron spin resonance (ESR). The Kondo effect leads to a common energy scale that regulates a logarithmic divergence of different spin kinetic coefficients and supports a collective spin motion of the Kondo ions with conduction electrons. We find that the relaxation rate of a collective spin mode is greatly reduced due to a mutual cancelation of all the divergent contributions even in the case of the strongly anisotropic Kondo interaction. The contribution to the ESR linewidth caused by the local magnetic field distribution is subject to motional narrowing supported by ferromagnetic correlations. The developed theoretical model successfully explains the ESR data of YbRh2Si2 in terms of their dependence on temperature and magnetic field.Comment: 5pages, 1 Figur