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

Evaluation of grain yield performance and its stability in various spring barley accessions under condition of different agroclimatic zones of Ukraine

Two extremely urgent problems of biological and agronomic research nowadays are ensuring an optimal balance between usage of natural resources to meet rapidly growing needs for food production and preservation of biodiversity. It is also important to extend the genetic diversity of the main crop varieties in agroecosystems. At the same time, modern varieties should be characterized by a combination of high yield and preserving yield stability under variable conditions. Solving the outlined tasks requires comprehensive research and involvement in breeding process of the genetical diversity concentrated in genebanks of the world. Barley (Hordeum vulgare L.) is one of the most important crops that satisfy the various needs of humanity. In respect to this, in 2020–2022, a multi-environment trial was conducted in three agroclimatic zones of Ukraine (Forest-Steppe, Polissia, and Northern Steppe). We studied 44 spring barley collection accessions of different ecological and geographical origin, different subspecies and groups of botanical varieties which were obtained from the National Center for Plant Genetic Resources of Ukraine. Statistical indices (Hom, Sc) and graphical models (GGE biplot, AMMI) were used to interpret the yield performance and its stability. Both individual ecological sites in different years and combinations of different sites and years of trials were characterized for productivity, discriminating power and representativeness. The environments differed quite strongly among themselves in terms of these indicators. It was established that most of the genotypes were characterized by higher adaptability to individual environmental conditions (stability in different years), compared to adaptability for all agroclimatic zones (wide adaptation). A strong cross-over genotype by environment interaction was found for most studied accessions. Nevertheless, both genotypes with very high stability in only one agroclimatic zone (Amil (UKR), Gateway (CAN)) and genotypes with a combination of high adaptability to one or two ecological niches and relatively higher wide adaptability (Stymul (UKR), Ly-1064 (UKR), Rannij (KAZ), Shedevr (UKR), and Arthur (CZE)) were identified. There were also the accessions which did not show maximum performance in the individual sites, but had relatively higher wide adaptability (Ly-1059 (UKR), Ly-1120 (UKR), Diantus (UKR), and Danielle (CZE)). In general, the naked barley genotypes were inferior to the covered ones in terms of yield potential and wide adaptability, but at the same time, some of them (CDC ExPlus (CAN), CDC Gainer (CAN), and Roseland (CAN)), accordingly to the statistical indicators, had increased stability in certain ecological sites. Among naked barley accessions relatively better wide adaptability according to the graphical analysis was found in the accession CDC McGwire (CAN), and by the statistical parameters CDC ExPlus (CAN) was better than standard. The peculiarities of yield manifestation and its variability in different spring barley genotypes in the multi-environment trial revealed in this study will contribute to the complementation and deepening of existing data in terms of the genotype by environment interaction. Our results can be used in further studies for developing spring barley variety models both with specific and wide adaptation under conditions of different agroclimatic zones of Ukraine. The disitnguished accessions of different origin and botanical affiliation are recommended for creating a new breeding material with the aim of simultaneously increasing yield potential and stability, as well as widening the genetic basis of spring barley varieties

Гістерезис електричного опору платинової нитки в холодних воднево-повітряних сумішах

Ignition of gaseous combustible mixtures on catalytically active hot solid surfaces has numerous applications in many industrial processes and is a complex process that involves close interaction between surface processes and transfer processes in the gas mixture. In this paper, stable and critical states catalytic oxidation of hydrogen impurities in air on a platinum filament are considered. It is shown that filament temperature and its resistance depending on the mixture temperature and hydrogen concentration are of the hysteresis features. Within this hysteresis region, it is possible to achieve the catalytic combustion mode of hydrogen as a result preheating the catalyst filament above a certain critical value. The dependence of the limiting hydrogen's concentration on catalyst filament's diameter, above which is observed in the cold gas mixture self-sustaining catalytic combustion without electric current.Займання газоподібних горючих сумішей на каталітично активних гарячих твердих поверхнях має численні застосування в багатьох промислових процесах і являє собою складний процес, що має на увазі тісну взаємодію між поверхневими процесами і процесами перенесення в газовій суміші. У даній роботі розглядаються стійкі і критичні стани каталітичного окислення домішки водню в повітрі на платиновій нитці. Показано, що температура нитки та її опір в залежності від температури навколишньої суміші і концентрації водню мають гістерезисний характер. Усередині даної гістерезисної області можливе досягнення режиму каталітичного горіння водню в результаті попереднього нагрівання нитки каталізатора вище певного критичного значення. Отримана залежність граничної концентрації водню від діаметра нитки каталізатора, вище якої спостерігається в холодній газовій суміші самопідтримується каталітичне горіння без протікання електричного струму

Critical Behaviour of 3D Systems with Long-Range Correlated Quenched Defects

A field-theoretic description of the critical behaviour of systems with quenched defects obeying a power law correlations $\sim |{\bf x}|^{-a}$ for large separations ${\bf x}$ is given. Directly for three-dimensional systems and different values of correlation parameter $2\leq a \leq 3$ a renormalization analysis of scaling function in the two-loop approximation is carried out, and the fixed points corresponding to stability of the various types of critical behaviour are identified. The obtained results essentially differ from results evaluated by double $\epsilon, \delta$ - expansion. The critical exponents in the two-loop approximation are calculated with the use of the Pade-Borel summation technique.Comment: Submitted to J. Phys. A, Letter to Editor 9 pages, 4 figure

Ionic Coulomb blockade and anomalous mole fraction effect in NaChBac bacterial ion channels

We report an experimental study of the influences of the fixed charge and bulk ionic concentrations on the conduction of biological ion channels, and we consider the results within the framework of the ionic Coulomb blockade model of permeation and selectivity. Voltage clamp recordings were used to investigate the Na$^+$/Ca$^{2+}$ anomalous mole fraction effect (AMFE) exhibited by the bacterial sodium channel NaChBac and its mutants. Site-directed mutagenesis was used to study the effect of either increasing or decreasing the fixed charge in their selectivity filters for comparison with the predictions of the Coulomb blockade model. The model was found to describe well some aspects of the experimental (divalent blockade and AMFE) and simulated (discrete multi-ion conduction and occupancy band) phenomena, including a concentration-dependent shift of the Coulomb staircase. These results substantially extend the understanding of ion channel selectivity and may also be applicable to biomimetic nanopores with charged walls

Peculiarities of Rendering English Phrasal Verbs into Ukrainian

The article studies English phrasal verbs in the aspect of translation. The subject of the paper appears to be of particular scientific interest as it concerns English phrasal verbs – complex combinations like to dash out, to count out, consisting of a monolexemic verb and a second component of a special adverbial and prepositional nature, which tend to be non-equivalent translation units, i.e. have no direct correspondences (equivalents) in the target language. The present study based on the particular empirical material (phrasal verbs with post-positive component out) suggests an attempt to single out and illustrate the principal ways of rendering verbal complexes under consideration into the Ukrainian language. The research carried out enables to distinguish two ways of translating the lexical units in question – morphological and syntactic. Morphological way implies rendering phrasal verbs by means of predominantly Ukrainian prefixal verbs, less likely – non-prefixal verbs, and syntactical – with the help of free or stable word combinations. It has been established that the translation ways indicated, on their turn, reflect the peculiarities of the typological status phrasal verb possesses in the English language, as it can serve as a compound/analytical verb with postpositive component in the function of the derivation formant or be used as a more or less free combination of a verb and a postpositive element of a distinct adverbial character. The assumption has been made that it is not only the categorical status of the phrasal verb that influences the choice of the way of its translation, but also the semantic type phrasal verbs under analysis refer to

Universal energy distribution for interfaces in a random field environment

We study the energy distribution function $\rho (E)$ for interfaces in a random field environment at zero temperature by summing the leading terms in the perturbation expansion of $\rho (E)$ in powers of the disorder strength, and by taking into account the non perturbational effects of the disorder using the functional renormalization group. We have found that the average and the variance of the energy for one-dimensional interface of length $L$ behave as, $_{R}\propto L\ln L$, $\Delta E_{R}\propto L$, while the distribution function of the energy tends for large $L$ to the Gumbel distribution of the extreme value statistics.Comment: 4 pages, 2 figures, revtex4; the distribution function of the total and the disorder energy is include

Novel highly charged silica-coated Tb(III) nanoparticles with fluorescent properties sensitive to ion exchange and energy transfer processes in aqueous dispersions

Novel silica-coated Tb(III) nanoparticles with high luminecsence were synthesized using the reverse microemulsion procedure. The quenching of luminescent properties of these nanoparticles can be achieved by ion exchange and energy transfer mechanisms. The quenching through the ion exchange of Tb(III) by H+ or La(III) is time dependent, indicating that the ion exchange is probably diffusion controlled. The quenching by Co(III) complex cations is achieved by the energy transfer mechanism and thus is not time dependent. The analysis of quenching data in Stern-Volmer cooordinates reveal the negative charge of the silica-coated Tb(III)-TCAS nanoparticles and several types of luminophoric species, located within the core and close to the surface of silica nanoparticles. © Copyright 2009 American Chemical Society