Symmetry adapted ro-vibrational basis functions for variational nuclear motion calculations: TROVE approach

We present a general, numerically motivated approach to the construction of symmetry adapted basis functions for solving ro-vibrational Schr\"{o}dinger equations. The approach is based on the property of the Hamiltonian operator to commute with the complete set of symmetry operators and hence to reflect the symmetry of the system. The symmetry adapted ro-vibrational basis set is constructed numerically by solving a set of reduced vibrational eigenvalue problems. In order to assign the irreducible representations associated with these eigenfunctions, their symmetry properties are probed on a grid of molecular geometries with the corresponding symmetry operations. The transformation matrices are re-constructed by solving over-determined systems of linear equations related to the transformation properties of the corresponding wavefunctions on the grid. Our method is implemented in the variational approach TROVE and has been successfully applied to a number of problems covering the most important molecular symmetry groups. Several examples are used to illustrate the procedure, which can be easily applied to different types of coordinates, basis sets, and molecular systems

The relationship between parameters of the peyer's patches of the small intestine in intact rats

This paper deals with the study of the relationship between parameters of the Peyer’s patches of the small intestine in intact rats of different age groups. The correlation analysis revealed the direct relationship between the parameter

Non-verbal means as a factor of attraction in English political Internet advertising

The article discusses the importance of non-verbal means of communication as stimulators of recipients’ interest and intensification of effectiveness of information provided on the websites of the British politicians.В статье рассматривается значимость невербальных средств коммуникации как стимуляров интереса реципиента и интенсификатов воздейственности представляемой на сайтах британских политиков информации

Rate of recovery of lichen-dominated tundra vegetation after overgrazing at the Yamal Peninsula ( Short Communication )

Lichens are the most sensitive part of vegetation cover to reindeer grazing. In this study we analyse success of restoration rate of lichen-rich tundra vegetation after ceasing the grazing stress at the Yamal Peninsula. On experimental plots we compare the main parameters of lichen mat (species diversity, total cover, thalii height, biomass, recovery rate) on grazed pastures and fanced sites after 13 years after of its isolation. Our results demonstrate that after intensive overgrazing the lichen species diversity and synusiases structure change very slowly. The rate of the biomass increase of lichens for this period has made 3.8 g m-2 year-1 that makes 3.6% from mass in the year. But this rate is two times lowers than in highly productive lichen communities

Salt marsh vegetation of the southern tundra subzone of Western Siberia: An example of the Baydaratskaya Bay coasts in the Kara Sea

The study is focused on the description of the vegetation and the general environment all characteristics of the salt marshes along coasts in the Baydaratskaya Bay there are of the Kara Sea in the southern tundra subzone of Russian Arctic. In tidal salt marsh habitats, several successional stages and types of communities depending on part of tidal zone. The plant communities study areas located close to research stations were represented by 50 species of vascular plant, 15 mosses and 3 lichens. The coastal vegetation tends to be floristically intermediate between the species composition of typical salt marshes communities (obligate and facultative halophytes) and species from adjacent tundra plains which can be able to tolerate occasional flooding by salt water. Zonation of salt marsh vegetation and floristic diversity were compared with the data for northern area of Kara Sea coasts

Effect of reindeer overgrazing on vegetation and animals of tundra ecosystems of the Yamal peninsula

Currently, 380 000 domestic reindeers are grazed on 106000 km2 of the Yamal peninsula. This unique situation was analyzed from a view of an ecosystem role of indigenous people. Attention was paied to two key points: the impact of overgrazing on (1) vegetation and (2) vertebrates. The results of our 30-years investigations were compared with the published vegetation data from the 1930-ies. In our paper, it is demonstrated, that overgrazing has resulted in a substantial transformation of vegetation, mostly in lichen tundra. Recent situation is close to total extinction of lichen pastures on the Yamal peninsula. Due to overgrazing, total availability of grasses and shrubs have also decreased, in grasses by 1.5-2.0 times, low shrubs - almost 8 times, tall shrubs – 2.0 times. The degradation of vegetation leads to desertification of the peninsula. The area of ​​sandy spots with no vegetation is on average about 5.5% of the peninsula land, however, it could reach up to 19% locally. Overgrazing affected the animal populations too. Since 1990, the peaks of lemmings have never reached former high values and become locally-limited and patchy. This has led to a decrease in the number of predators. The number of other tundra birds decreased as well. The decrease reached almost 2 times lower numbers in geese, 3 times in hygrophillous waders, 5.5 times in Lapland bunting, and 2 times in long-tailed Duck and Willow grouse on watershed. The Nenets themselves can not control reindeer population because of rigid social and psychological attitudes based on their traditions. The main aim of the Nenets reindeer-farming is not to create marketable products for a profit, but increasing the reindeer number of itself. A situation has formed, that, on the one hand, the Nenets are not economically dependent upon the society, and on the other hand, the society contributes to preservation of their traditional farming. The Nenets reindeer-farming, thus become an important factor contributing to rapid transformation of tundra ecosystem

Lithium Kolmozero deposit of rare metal pegmatites: New data on rare element composition (Kola Peninsula)

The article is devoted to studies the rare element composition of albite-spodumene pegmatites of the lithium with associated Be, Nb, Ta Kolmozero deposit. It is located in the Neoarchaean metagabbro-anorthozites Patchemvareksky massif in the junction zone of the two major regional structures Archaean age, i.e. the Murmansk block and the Kolmozero-Voron’ya Greenstone Belt of the Kola region. The albite-spodumene pegmatites are identified to be rich in highly incompatible ore elements, i.e. Li, Ta, Nb and Be, depleted by large-ion lithophile elements (Ba ≤ 20 ppm; Sr ≤ 15.4 ppm) and high field strength elements (Y≤ 0.46 ppm, Th ≤ 2.5 ppm, ∑REE ≤ 3 ppm). They are characterized by low indexes of fractioning (Mg/Li ≤ 0.05, Zr/Hf ≤ 7.4) and a high index of rare metal content (Ir = 167321). It may be used as criteria for estimating the commercial potential of the pegmatites regarding their rare metal mineralization. The feldspar (beryllium-bearing) and muscovite-feldspar (beryllium-niobium-tantalum) pegmatites jointed with the Kolmozero deposit have rare metal mineralization and, like albite-spodumene pegmatites, are rich in Li, Nb, Ta, Be, Rb and depleted by Sr, Ва , Y, REE

NMR and LDA evidence for spiral magnetic order in the chain cuprate LiCu2O2

We report on {6,7}Li nuclear magnetic resonance measurements of the spin-chain compound LiCu2O2 in the paramagnetic and magnetically ordered states. Below T about 24 K the NMR lineshape presents a clear signature of incommensurate (IC) static modulation of the local magnetic field consistent with an IC spiral modulation of the magnetic moments. {7}Li NMR reveals strong phason-like dynamical fluctuations extending well below 24 K. We hypothesize that a series of phase transitions at 24.2, 22.5, and 9 K reflects a "Devil's staircase" type behavior generic for IC systems. LDA based calculations of exchange integrals reveal a large in-chain frustration leading to a magnetical spiral.Comment: 4 pages, 4 figure