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In higher eukaryotes, distance enhancer-promoter interactions are organized by topologically associated domains, tethering elements, and chromatin insulators/boundaries. While insulators/boundaries play a central role in chromosome organization, the mechanisms regulating their functions are largely unknown. In the studies reported here, we have taken advantage of the well-characterized Drosophila bithorax complex (BX-C) to study one potential mechanism for controlling boundary function. The regulatory domains of BX-C are flanked by boundaries, which block crosstalk with their neighboring domains and also support long-distance interactions between the regulatory domains and their target gene. As many lncRNAs have been found in BX-C, we asked whether readthrough transcription (RT) can impact boundary function. For this purpose, we took advantage of two BX-C boundary replacement platforms, Fab-7attP50 and F2attP, in which the Fab-7 and Fub boundaries, respectively, are deleted and replaced with an attP site. We introduced boundary elements, promoters, and polyadenylation signals arranged in different combinations and then assayed for boundary function. Our results show that RT can interfere with boundary activity. Since lncRNAs represent a significant fraction of Pol II transcripts in multicellular eukaryotes, it is therefore possible that RT may be a widely used mechanism to alter boundary function and regulation of gene expression. [ABSTRACT FROM AUTHOR]

In higher eukaryotes, the regulation of developmental gene expression is determined by enhancers, which are often located at a large distance from the promoters they regulate. Therefore, the architecture of chromosomes and the mechanisms that determine the functional interaction between enhancers and promoters are of decisive importance in the development of organisms. Mammals and the model animal Drosophila have homologous key architectural proteins and similar mechanisms in the organization of chromosome architecture. This review describes the current progress in understanding the mechanisms of the formation and regulation of long-range interactions between enhancers and promoters at three well-studied key regulatory loci in Drosophila. [ABSTRACT FROM AUTHOR]

Reduction of 1,2-bis[(2,6-dibenzhydryl-4-methylphenyl)imino] acenaphthene (ArBIG-bian) with an excess of magnesium in tetrahydrofuran (thf) or with an excess of calcium in 1,2-dimethoxyethane (dme) and crystallization of the crude products from the reaction mixtures affords monomeric complexes [(ArBIG-bian)Mg(thf)2] (1) or [(ArBIG-bian)Ca(dme)2] (2), respectively. Hydrolysis of complex 1 affords metal-free diamine [ArBIGbianH2(thf)] (3). Complexes 1 and 2 readily react with CO2 to form the corresponding carbamates [(ArBIG-bian)(CO2)2Mg(thf)2] (4) and [(ArBIG-bian)(CO2)2Ca(dme)2] (5). Compounds 1-5 have been characterized by NMR and IR spectroscopy as well as elemental analysis. The molecular structures of 1, 2, 3, and 5 have been determined by the single crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

Relations between triple Jordan systems and integrable multi-component models of the modified Korteveg–de Vries type are established. The most general model is related to a pair consisting of a triple Jordan system and a skew-symmetric bilinear operation. If this operation is a Lie bracket, then we arrive at the Lie–Jordan algebras [Speciality of Lie–Jordan algebras, J. Algebra237 (2001) 621–636]. [ABSTRACT FROM AUTHOR]

The reaction of dialane [LAl‐AlL] (1; L=dianion of 1,2‐bis[(2,6‐diisopropylphenyl)imino]acenaphthene, dpp‐bian) with carbon dioxide results in two different products depending on solvent. In toluene at temperatures of about 0 °C, the reaction gives cycloadduct [L(CO2)Al‐Al(O2C)L] (2), whereas in diethyl ether, the reaction affords oxo‐bridged carbamato derivative [L(CO2)(Et2O)Al(μ‐O)AlL] (3). The DFT and QTAIM calculations provide reasonable explanations for the reversible formation of complex 2 in the course of two subsequent (2+4) cycloaddition reactions. Consecutive transition states with low activation barriers were revealed. Also, the DFT study demonstrated a crucial effect of diethyl ether coordination to aluminium on the reaction of dialane 1 with CO2. The optimized structures of key intermediates were obtained for the reactions in the presence of Et2O; calculated thermodynamic parameters unambiguously testify the irreversible formation of the product 3. [ABSTRACT FROM AUTHOR]

Using an original method, we have received Drosophila melanogaster with a deficiency including a complete sequence of quick-to-court gene. In this report, we describe the behavioural features of this new deletion mutant. There were no serious deviations from the normal mating behaviour in flies with the deletion, but the behaviour of deletion mutants still had some features. Of all the elements, only the frequency of licking significantly increased in mutants. The duration of mating elements did not change in flies with deletion, and the latent period decreased only for following the female and licking. We have found that mutant males produce more courtship song than control males when courting Oregon R females as estimated by the pulse song index. In our experiment, mutant females provoked much less pulse song production by Oregon R males than control females do. Moreover, Oregon R males initiate courtship song towards mutant females later than towards control females. In other words, the study of pulse song production showed that the deficiency in females leads to a decrease in the intensity of courtship of wild-type males, whereas the deficiency in males leads to more intensive care for wild-type females. [ABSTRACT FROM AUTHOR]

Reduction of ArBIG-bian (1, 1,2-bis[(2,6-dibenzhydryl-4-methylphenyl)imino]acenaphthene) with an excess of samarium in tetrahydrofuran (thf) and crystallization of the crude product from a thf/toluene mixture affords [(ArBIG-bian)Sm]·C7H8 (2a), which is free of the coordinating solvent. The use of 1,2-dimethoxyethane (dme) as the reaction medium resulted in the same product, [(ArBIG-bian)Sm]·C4H10O2 (2b), which differs from 2a only in the crystal lattice solvent. Reduction of 1 with an excess of ytterbium in dme gives compound [(ArBIG-bian)Yb(dme)]·2.5C7H8 (3), containing a coordinated dme molecule. All three products consist of dianionic ArBIG-bian ligands whose bulky 2,6-(Ph2CH)2-4-Me–C6H2 groups shield effectively the metal atoms. The newly prepared compounds 2a, 2b and 3 were characterized by 1H NMR and IR spectroscopy. The molecular structures of complexes 2a, 2b and 3 have been established by single crystal X-ray analysis. The intramolecular interactions were analysed on the basis of DFT calculations. The temperature dependence of the magnetic susceptibility of 2b and 3 in the region of 2–300 K was studied. The magnetic moments of complex 2b correspond to divalent samarium. [ABSTRACT FROM AUTHOR]

A new series of homobivalent Dimebon analogs, bis-γ-carbolines with alkylene, phenylenedialkylene, and triazole-containing spacers, was synthesized. Doubling the γ-carboline pharmacophore increased inhibitory potency against acetylcholinesterase (AChE) compared with Dimebon, while keeping Dimebon's anti-butyrylcholinesterase activity; therefore, leading to inversion of selectivity. Molecular docking revealed the reasons for the increased anti-AChE activity and ability to block AChE-induced aggregation of β-amyloid for bis-γ-carbolines, which became double-site inhibitors of AChE. Conjugates with ditriazole-containing spacers were the most active antioxidants in both the ABTS-test and prevention of lipid peroxidation in brain homogenates without inhibiting the mitochondrial permeability transition (MPT). Conjugates with alkylene (4a–d), phenylenedialkylene (4e), and monotriazole (8) spacers were less active as antioxidants but prevented induction of the MPT and increased the calcium retention capacity of mitochondria. Lead compound 4e showed neuroprotective potential in a cellular calcium overload model of neurodegeneration. Computational studies showed that all the bis-γ-carbolines were expected to have high values for intestinal absorption and very good blood-brain barrier permeability along with good drug-likeness. Overall, the results showed that new homobivalent Dimebon analogs exhibit an expanded spectrum of biological activity and improved pharmacological properties, making them promising candidates for further research and optimization as multitarget agents for Alzheimer's disease treatment. [ABSTRACT FROM AUTHOR]

The late Quaternary climatic and environmental history of the Severnaya Zemlya Archipelago in the Russian High Arctic has been the focus of many palaeoenvironmental studies since the 1970s. However, the existing data are highly fragmentary and sometimes contradictory. New information concerning the archipelago's environmental history was derived from a 2.46‐m‐long sediment core from Lake Tvyordoe, located in the northwestern part of Bolshevik Island. The core was investigated by a multi‐proxy approach that comprises radiocarbon dating as well as lithological, granulometrical, palynological and geochemical analyses. The results provide new insights into the vegetation history as well as changes in lake level, lake‐ice cover, and water and sediment input since the Last Glacial Maximum (LGM). Fine‐grained, laminated sediments at the core base, which were dated to c. 24.2 cal. ka BP, suggest lacustrine sedimentation under a permanent ice cover with low meltwater supply. This, along with a lack of glacial and glacial‐lacustrine deposits, supports earlier assumptions that Bolshevik Island was not covered by the Barents‐Kara Ice Sheet during the LGM. Furthermore, even the Mushketov Ice Cap, the closest ice mass to Lake Tvyordoe, did not expand from the denudation plateau to the lake. During the terminal Pleistocene, starting c. 14.5 cal. ka BP, warmer and wetter climate conditions resulted in higher sediment loads. The most favourable environmental conditions prevailed on Bolshevik Island throughout the Early and Middle Holocene (c. 11.7–6.5 cal. ka BP), when low shrub tundra associations with dwarf birch, willow and alder dominated the vegetation. After c. 10.0 cal. ka BP, a shift to climate drying occurred, which, after 6.5 cal. ka BP, was accompanied by a climate cooling. The Late Holocene climate, according to pollen data (suggesting sparse lichen–moss–grass cover) and relatively low total organic carbon (TOC) contents, was rather similar to that during the Lateglacial. [ABSTRACT FROM AUTHOR]

Vibrational spectra of methyl C-H stretching region are notoriously complicated, and thus a theoretical method of systematic assignment is strongly called for in condensed phase. Here we develop a unified analysis method of the vibrational spectra, such as infrared (IR), polarized and depolarized Raman, and ssp polarized sum frequency generation (SFG), by flexible and polarizable molecular dynamics simulation. The molecular model for methanol has been developed by charge response kernel model to allow for analyzing the methyl C-H stretching vibrations. The complicated spectral structure by the Fermi resonance has been unraveled by empirically shifting potential parameters, which provides clear information on the coupling mechanism. The analysis confirmed that for the IR, polarized Raman, and SFG spectra, two-band structure at about 2830 and 2950 cm-1 results from the Fermi resonance splitting of the methyl C-H symmetric stretching and bending overtones. In the IR spectrum, the latter, higher-frequency band is overlapped with prominent asymmetric C-H stretching bands. In the depolarized Raman spectrum, the high frequency band at about 2980 cm-1 is assigned to the asymmetric C-H stretching mode. In the SFG spectrum, the two bands of the splitted symmetric C-H stretching mode have negative amplitudes of imaginary nonlinear susceptibility χ(2), while the higher-frequency band is partly cancelled by positive imaginary components of asymmetric C-H stretching modes. [ABSTRACT FROM AUTHOR]

A flexible and polarizable methanol model has been developed on the basis of charge response kernel (CRK) theory. The present CRK methanol model well reproduces bulk liquid and interfacial properties, including density, enthalpy of vaporization, diffusion coefficient, surface tension, and radial distribution functions. The modeling of intramolecular potential incorporates the anharmonic coupling effects pertinent to the Fermi resonance of stretching and bending overtones, with its effective quantum correction. Therefore, the present methanol model can describe the vibrational spectroscopic features of infrared, Raman, and sum frequency generation spectra of C-H or C-D stretching region of methanol or deuterated methanol on the same footing. This model allows for further detailed analysis of C-H vibrations of alkyl moieties by molecular dynamics simulation. [ABSTRACT FROM AUTHOR]

The Zeeman effect has been studied within the “green” range of luminescence due to the radiative 4f→4f transitions 5D4→7F5 for the rare earth ion Tb3+ in yttrium aluminum garnet (Y3Al5O12) at a sample temperature of 85 K. The special features associated with the magnetic field dependence of the Zeeman splitting have been explained for transitions observed in the geometry of the longitudinal and transverse Zeeman effect. An analysis of the results obtained from the magneto-optical data indicates that in a magnetic field a nonequilibrium population distribution occurs between the sublevels of the quasidoublet state (Γ1,Γ4) in the 5D4 manifold. The energy of the quasidoublet state is approximately 20 585 cm-1. [ABSTRACT FROM AUTHOR]

New simple expressions for average number of electrons in the valence orbital of a reacting ion and the charge susceptibility are obtained that allow one to calculate adiabatic free energy surfaces (AFES) and corresponding kinetic regime diagrams (KRD) for adiabatic processes of electron transfer from the ion, located in a polar liquid, to a metal within the framework of the exactly solvable (in the limit T→0) model of the metal with the infinitely wide conduction band. This model represents one of limiting cases of the Anderson model that may be applied to s–p metals. Unlike previous studies of the adiabatic reactions in the model of the metal with the infinitely wide conduction band, the present work takes into account the electron–electron correlation effects in an exact manner. General results are illustrated with KRD which determine the regions of the physical parameters of the system corresponding to various types of electron transfer processes. AFES are calculated for some typical parameters sets. The exact AFES are compared with those calculated within the Hartree–Fock approximation. It is shown that the correlation effects are of importance and results not only in a considerable decrease of the activation free energy but also to qualitatively different shapes of AFES in some regions of the system parameters. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The first representative of N1-substituted N2-thiiranylmethylethaneamides has been synthesized from N1-substituted N2-allylethaneamides. The formation of thiiranylmethylamides passes through bromine-induced cyclization of N-allylthioamide moiety followed by hydrolysis of 5-bromomethyl-1,3-thiazoline ring. [ABSTRACT FROM AUTHOR]

Neuronal excitotoxicity which is induced by exposure to excessive extracellular glutamate is shown to be involved in neuronal cell death in acute brain injury and a number of neurological diseases. High concentration of glutamate induces calcium deregulation which results in mitochondrial calcium overload and mitochondrial depolarization that triggers the mechanism of cell death. Inhibition of mitochondrial calcium uptake could be potentially neuroprotective but complete inhibition of mitochondrial calcium uniporter could result in the loss of some physiological processes linked to Ca2+ in mitochondria. Here, we found that a novel compound, TG-2112x, can inhibit only the lower concentrations mitochondrial calcium uptake (induced by 100 nM-5 μM) but not the uptake induced by higher concentrations of calcium (10 μM and higher). This effect was not associated with changes in mitochondrial membrane potential and cellular respiration. However, a pre-treatment of neurons with TG-2112x protected the neurons against calcium overload upon application of toxic concentrations of glutamate. Thus, sequestration of mitochondrial calcium uptake protected the neurons against glutamate-induced mitochondrial depolarization and cell death. In our hands, TG-2112x was also protective against ionomycin-induced cell death. Hence, low rate mitochondrial calcium uptake plays an underestimated role in mitochondrial function, and its inhibition could protect neurons against calcium overload and cell death in glutamate excitotoxicity. [ABSTRACT FROM AUTHOR]

We exploit variation in consumer price inflation across seventy-one Russian regions to examine the relationship between the perceived stability of the domestic currency and financial dollarization. Our results show that regions with higher inflation experience an increase in the dollarization of household deposits and a decrease in the dollarization of loans. The impact of inflation on credit dollarization is weaker in regions with less integrated banking markets. This suggests that the currency-portfolio choices of households and firms are constrained by the asset-liability management of banks. [ABSTRACT FROM AUTHOR]

Abstract: The reaction of digallane (dpp‐bian)Ga−Ga(dpp‐bian) (2) (dpp‐bian=1,2‐bis[(2,6‐diisopropylphenyl)imino]acenaphthene) with allyl chloride (AllCl) proceeded by a two‐electron oxidative addition to afford paramagnetic complexes (dpp‐bian)Ga(η1‐All)Cl (3) and (dpp‐bian)(Cl)Ga−Ga(Cl)(dpp‐bian) (4). Treatment of complex 4 with pyridine induced an intramolecular redox process, which resulted in the diamagnetic complex (dpp‐bian)Ga(Py)Cl (5). In reaction with allyl bromide, complex 2 gave metal‐ and ligand‐centered addition products (dpp‐bian)Ga(η1‐All)Br (6) and (dpp‐bian‐All)(Br)Ga−Ga(Br)(dpp‐bian‐All) (7). The reaction of digallane 2 with Ph3SnNCO afforded (dpp‐bian)Ga(SnPh3)2 (8) and (dpp‐bian)(NCO)Ga−Ga(NCO)(dpp‐bian) (9). Treatment of GaCl3 with (dpp‐bian)Na in diethyl ether resulted in the formation of (dpp‐bian)GaCl2 (10). Diorganylgallium derivatives (dpp‐bian)GaR2 (R=Ph, 11; tBu, 14; Me, 15; Bn, 16) and (dpp‐bian)Ga(η1‐All)R (R=nBu, 12; Cp, 13) were synthesized from complexes 3, 10, Bn2GaCl, or tBu2GaCl by salt metathesis. The salt elimination reaction between (dpp‐bian)GaI2 (17) and tBuLi was accompanied by reduction of both the metal and the dpp‐bian ligand, which resulted in digallane 2 as the final product. Similarly, the reaction of complex 10 with MentMgCl (Ment=menthyl) proceeded with reduction of the dpp‐bian ligand to give the diamagnetic complex [(dpp‐bian)GaCl2][Mg2Cl3(THF)6] (18). Compounds 11, 12, 13, 15, and 16 were thermally robust, whereas compound 14 decomposed when heated at reflux in toluene to give complex (dpp‐bian‐tBu)GatBu2 (19). Both complexes 7 and 19 contain R‐substituted dpp‐bian ligand: in the former compound the allyl group was attached to the imino‐carbon atom, whereas in complex 19, the tBu group was situated on the naphthalene ring. Crystal structures of complexes 3, 8, 9, 10, 13, 14, 18, and 19 were determined by single‐crystal X‐ray analysis. The presence of dpp‐bian radical anions in 3, 6, 8, and 10–16 was determined by ESR spectroscopy. [ABSTRACT FROM AUTHOR]

A comparative study performed in mice investigating the action of DF302, a novel fluoride-containing gamma-carboline derivative, in comparison to the structurally similar neuroprotective drug dimebon. Drug effects on learning and memory, emotionality, hippocampal neurogenesis and mitochondrial functions, as well as AMPA-mediated currents and the 5-HT6 receptor are reported. In the step-down avoidance and fear-conditioning paradigms, bolus administration of drugs at doses of 10 or 40 mg/kg showed that only the higher dose of DF302 improved long-term memory while dimebon was ineffective at either dosage. Short-term memory and fear extinction remained unaltered across treatment groups. During the 5-day predation stress paradigm, oral drug treatment over a period of 2 weeks at the higher dosage regimen decreased anxiety-like behaviour. Both compounds supressed inter-male aggression in CD1 mice, the most eminent being the effects of DF302 in its highest dose. DF302 at the higher dose decreased floating behaviour in a 2-day swim test and after 21-day ultrasound stress. The density of Ki67-positive cells, a marker of adult neurogenesis, was reduced in the dentate gyrus of stressed dimebon-treated and non-treated mice, but not in DF302-treated mice. Non-stressed mice that received DF302 had a higher density of Ki67-positive cells than controls unlike dimebon-treated mice. Similar to dimebon, DF302 effectively potentiated AMPA receptor-mediated currents, bound to the 5-HT6 receptor, inhibited mitochondrial permeability transition and displayed cytoprotective properties in cellular models of neurodegeneration. Thus, DF302 exerts multi-target effects on the key mechanisms of neurodegenerative pathologies and can be considered as an optimized novel analogue of the neuroprotective agent dimebon. [ABSTRACT FROM AUTHOR]

Alzheimer's disease has a complex multifactorial nature; therefore, a promising approach for the development of efficient therapeutic agents is the concept of multitarget drugs, which affect several biological targets involved in the pathogenesis of the disease. We developed a synthetic algorithm for conjugating several pharmacophoric ligands acting on the key stages of pathogenesis of several neurodegenerative diseases and synthesized hybrid structures combining the γ-carboline fragment of Dimebon with carbazole and tetrahydrocarbazole moieties. Using the complex primary screening system the structures have been revealed that combine the high inhibitory activity and selectivity towards butyrylcholinesterase with the radical-scavenging activity and the ability to potentiate tubulin polymerization to microtubules with a normal structure and/or prevent mitochondrial permeability transition. The lead compound was identified for future optimization and development of new multi-target drugs against neurodegenerative diseases combining the cognitive-stimulating and neuroprotective potentials. [ABSTRACT FROM AUTHOR]

Biodiversity and number of airborne fungi isolated from indoor and outdoor air of different location in the areas of arctic settlement Tiksi (Russian Arctic) are described. Different locations (coastal areas, landscape, streets of Tiksi, abandoned empty houses, flats, public buildings) were observed. Aeromycota characterized by a significant biodiversity (50 species), but only several species were abundant. Airborne fungal spores concentration (CFU) in Tiksi locations was found low. The maximum spore concentrations were observed in air of the abandoned empty houses (inhabited in the past). Many species common for soil were observed at the samples taken at streets and abandoned buildings. Most of them are also known as inhabitants of building materials. Microfungi CFU at settlement territory was twice as high as natural territory. Phospholipase, albuminase and hemolytic activities of microfungi isolates as well as their relation to temperature were studied. Most of the tested isolates demonstrated high levels of all the tested activities. It was concluded that there is a risk of "mold" allergy diseases for the people especially with weakening of immunity at arctic settlement Tiksi. Main sources of the air contamination in arctic settlements and houses could be many anthropogenic substrates which were colonized by soil fungi. [ABSTRACT FROM AUTHOR]

We analyze the results of a Probabilistic Seismic Hazard Assessment obtained for Saudi Arabia using a spatially smoothed seismicity model. The composite up-to-date earthquake catalog is used to model seismicity and to determine earthquake recurrence characteristics. Different techniques that are frequently used for the analysis of input data are applied in the study. The alternative techniques include the declustering procedures for catalog processing, statistical techniques for estimation the magnitude-frequency relationship (MFR), and the seismicity smoothing parameter. The scheme represents epistemic uncertainty that results from an incomplete knowledge of earthquake process and application of alternative mathematical models for a description of the process. Our calculations that are based on the Monte Carlo technique include also a consideration of the aleatory uncertainty related to the dimensions and depths of earthquake sources, parameters of MFR, and scatter of ground-motion parameter. The hazard maps show that the rock-site peak ground acceleration (PGA) is the highest for the seismically active areas in the north-western (Gulf of Aqaba, PGA > 300 cm/s for return period 2475 years) and south-western (PGA > 100 cm/s for return period 2475 years) parts of the country. We show that the procedures for catalog declustering have the highest influence on the results of hazard estimations, especially for high levels of hazard. The choice of smoothing parameter is a very important decision that requires proper caution. The relative uncertainty that is ratio between the 85th and 15th percentiles may reach 50-60% for the areas located near the zones of high-level seismic activity. [ABSTRACT FROM AUTHOR]

An approach to seismic hazard assessment that is based on consideration of spatial distribution of possible earthquakes with maximum credible magnitudes is proposed. A set of catalogs consisting in a large number of the earthquakes randomly distributed inside seismic source areas is generated using Monte Carlo technique. Magnitudes and parameters of the earthquake sources are considered as random variables with corresponding probability distribution functions. The modeling takes into account inherent uncertainty in location, magnitude, size of faulting and other characteristics of future large earthquakes. The ground-motion parameters at the point of interest are calculated from all events in the catalogs using ground motion prediction equations taking into account ground-motion variability. Seismic hazard for every site is described by a set of possible values of the ground-motion parameters, from which probability density function and cumulative distribution function are determined. The approach is discussed in application to region of western Saudi Arabia which is characterized by various levels of seismicity. Such type of seismic hazard analysis may be useful to constrain the expected level of maximum ground motion to be considered in design, seismic risk mitigation and reinsurance, bearing in mind necessity for estimations of ground motions from large rare earthquakes. [ABSTRACT FROM AUTHOR]

We examine how regional-level political influence affects firm financial performance and survival. Combining representative survey data on mid-sized manufacturing firms in Russia with official registry data, we find that politically influential firms exhibit higher profitability and retain larger financial investments than non-influential firms. At the same time, we find no association between regional political influence and access to bank lending. Most importantly, our empirical analysis suggests that the benefits of influence may be transient. Influential firms experienced significantly lower growth during our 2004--2010 sample period than non-influential firms. Moreover, influential firms had a significantly higher probability of going bankrupt after the 2008 global financial crisis than non-influential firms. [ABSTRACT FROM AUTHOR]

The article presents cross-sectional results related to political influence and firm performance in the longer term. Topics include examination of growth in return on assets, the growth rate of total revenue and changes in leverage, less growth of influential firms, and collapse of global financial markets and decline in crude oil prices.

The article provides annual data related to impact of political influence on firm's performance. It discusses empirical model for performance measures of the firm based on profitability, growth and leverage. It also reveals a benchmark model for standard firm-level control variables such as leverage, net working capital and revenue growth.

The article presents a survey data quantifying the impact of political influence on firm's performance. Topics include role of enterprises in providing social services and local infrastructure, assessments of public infrastructure, role of larger firms in regional political decision-making, and focusing on accounting variables like return on assets (ROA).

A new seismic source model has been developed for the western part of the Arabian Peninsula, which has experienced considerable earthquake activity in the historical past and in recent times. The data used for the model include an up-to-date seismic catalog, results of recent studies of Cenozoic faulting in the area, aeromagnetic anomaly and gravity maps, geological maps, and miscellaneous information on volcanic activity. The model includes 18 zones ranging along the Red Sea and the Arabian Peninsula from the Gulf of Aqaba and the Dead Sea in the north to the Gulf of Aden in the south. The seismic source model developed in this study may be considered as one of the basic branches in a logic tree approach for seismic hazard assessment in Saudi Arabia and adjacent territories. [ABSTRACT FROM AUTHOR]

We focused on validation of applicability of semi-empirical technique (spectral models and stochastic simulation) for the estimation of ground-motion characteristics in the northeastern region (NER) of India. In the present study, it is assumed that the point source approximation in far field is valid. The one-dimensional stochastic point source seismological model of Boore (1983) (Boore, DM. 1983. Stochastic simulation of high frequency ground motions based on seismological models of the radiated spectra. Bulletin of Seismological Society of America, 73, 1865–1894.) is used for modelling the acceleration time histories. Total ground-motion records of 30 earthquakes of magnitudes lying betweenMW4.2 and 6.2 in NER India from March 2008 to April 2013 are used for this study. We considered peak ground acceleration (PGA) and pseudospectral acceleration (response spectrum amplitudes) with 5% damping ratio at three fundamental natural periods, namely: 0.3, 1.0, and 3.0 s. The spectral models, which work well for PGA, overestimate the pseudospectral acceleration. It seems that there is a strong influence of local site amplification and crustal attenuation (kappa), which control spectral amplitudes at different frequencies. The results would allow analysing regional peculiarities of ground-motion excitation and propagation and updating seismic hazard assessment, both the probabilistic and deterministic approaches. [ABSTRACT FROM PUBLISHER]

The results of classical probabilistic seismic hazard analysis (PSHA) contain no information about simultaneous ground motions at different sites during a particular earthquake. Seismic risk analysis for distributed critical structures requires estimates of the level of earthquake shaking that are likely to occur concurrently at multiple locations: whether the vulnerable elements of a lifeline system are likely to be simultaneously affected by shaking of sufficient strength to disable them and whether the shaking at any one of critical points may be sufficient to cause failure of the whole system. While the analysis of lifeline performance requires multiple-location estimations, the sparsely located elements of a network or critical facilities are designed on the basis of point-wise PSHA. In this paper we study specific features of multiple-location PSHA, as compared with the classical point-wise PSHA, using Monte Carlo simulations. We analyze the level of ground motion (PGA) that will be exceeded at any site inside a particular area or at several sites simultaneously with reference annual probability. The analysis has been performed for regions of Western and South-Western Germany, Northern and Eastern Taiwan, which represent different levels of seismicity (low, moderate and high, respectively). The relationship between the multiple-location and point-wise estimations are analyzed and quantified. Results of the study may be used to decide whether it may be possible to utilize the procedure of point-wise PSHA in particular cases of multiple-location PSHA, i.e. for assessment of maximum level of ground motion among several sites, or for estimation a reasonable lower safety level when considering simultaneous exceedances. [ABSTRACT FROM AUTHOR]

Electron temperature gradient (ETG) modes are suspected sources of anomalous electron thermal transport in magnetically confined plasmas as in tokamaks. Prior work in the Columbia Linear Machine (CLM) has been able to produce and identify slab ETG modes in a slab geometry [Wei et al., Phys. Plasmas 17, 042108 (2010)]. Now by modifying CLM to introduce curvature to the confining axial magnetic field, we have excited mixed slab-toroidal modes. Linear theory predicts a transition between slab and toroidal ETG modes when ... [J. Kim and W. Horton, Phys. Fluids B 3, 1167 (1991)]. We observe changes in the mode amplitude for levels of curvature Rc-1 ..., which may be explained by reductions in k‖ in the transition from slab to mixed slab-toroidal modes, as also predicted by theory. We present mode amplitude scaling as a function of magnetic field curvature. Over the range of curvature available in CLM experimentally we find a modest increase in saturated ETG potential fluctuations (~1.5×), and a substantial increase in the power density of individual mode peaks (~4-5×). [ABSTRACT FROM AUTHOR]

Consideration of within-earthquake ground-motion correlation is essential for the estimation of seismic hazards, damage, and loss for spatially distributed systems. In many seismically active regions, the strong motion data of real engineering significance are completely unavailable or very scarce. The absence of necessary data does not allow developing regional empirical correlation models, and the models obtained for other regions should be used with correspondent sensitivity analysis. The level of within-earthquake correlation may vary in broad range; therefore, development of correspondent criteria for selection from available models is important. In this paper, we analyzed the performance of a system of critical elements of electric power network (substations) depending on variations in within-earthquake correlation. The performance is described as probability of different levels of non-functionality, i.e., percentage of area suffering power outage, and probability of expected number of customers without power. We have shown that the proper choice of the within-earthquake correlation model is critical in comprehensive estimations of functionality of substations in electrical power system. Skipping the ground-motion variability and within-earthquake correlation may lead to unreliable results. Relevance of geology-based within-earthquake correlation models has been demonstrated, and a scheme, which allows reducing uncertainty in the choice of realistic correlation, has been proposed. [ABSTRACT FROM AUTHOR]

We discuss associative analogues of classical Yang-Baxter equation (CYBE) meromorphically dependent on parameters. We discover that such equations enter in a description of a general class of parameter-dependent Poisson structures and double Lie and Poisson structures in sense of Van den Bergh. We propose a classification of all solutions for one-dimensional associative Yang-Baxter equations (AYBE). [ABSTRACT FROM AUTHOR]