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The automated design issues of modular spindle heads for multi-operational metalcutting machines are considered. An option for expanding technological capabilities through the use of forming units with vertical and horizontal arrangement in the space of the machine working area is given. A 3D project for the drive of the machine's main movement with a built-in horizontal spindle head and replaceable vertical and slotting spindle heads has been developed. In the process of modelling complex drive housing parts and replaceable heads, Creo Parametric CAD functionality was developed. These functionalities with the procedure for interconnecting the three-dimensional design model and the manufactured casting mold are associated. The implementation of this procedure using the example of creating a structural element - a "Casting draft angle" in the housing part manufacturing of a slotting head is presented. The "Mechanism Design" module of the Creo Parametric CAD system models the rack-and-pinion transmission as the translationally moving link intended for processing grooves, blind-shaped surfaces, and internal cavities is used. Ways to improve the design of the rack-and-pinion gear are outlined. The main innovative idea of the rack tooth profile in the form of an arched shape is presentation. Primary analytical dependencies for a complex geometric-kinematic analysis of a rack-and-pinion transmission with arched teeth were obtained. The relationship between transmission parameters and the maximum size of the gear-cutting head has been established. A condition to guarantee the absence of secondary cutting using a gear-cutting head has been introduced. The value of the coefficient KL = 1.13 as an indicator of a decrease in bending stress and, as a consequence, an increase in the load capacity of arched teeth in comparison with straight rack and pinion teeth, all other things being equal is determined. [ABSTRACT FROM AUTHOR]

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]

- The design of the main movement drive for a multioperational machine such as a machining center with a modified design of a gear gearbox is considered. A 3D modelling of the machining center drive mechanism with a portal layout was performed in the integrated computeraided design system KOMPAS-3D. Functional extended range of the C3D Modeler geometric kernel when constructing complex geometry of machine housing parts is proposed to use. The procedure for constructing gear rims with high accuracy and geometrically correct tooth surfaces in the CAD environment was applied. At the stage of forming the shape of the tooth of a multivariate choice of the tooth axial shape, it is possible to implement. A new idea to increase the efficiency of the cylindrical gear transmission of the machine speed box based on the modified tooth profile of the gears with inclined-arched teeth is put forward. An analytical apparatus for calculating the design and choosing the radius of the gear-shaping cutting head with known basic transmission parameters have been formed. A comparative analysis for the calculated values of the axial overlap coefficient in an involute helical spur gear and in a spur gear with inclined-arched teeth is carried out with the same engagement parameters, other conditions being equal. Numerical calculations for the modified version of the engagement with inclined-arched teeth compared with the involute helical gear in terms of load capacity have been shown. [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]

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]

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]

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]

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]

We create and test a framework for probabilistic seismic hazard assessment for the Kingdom of Saudi Arabia using Monte Carlo simulation, recently developed models of seismic source zones and modern ground-motion prediction equations (GMPE). A generalized seismic source model containing 43 zones has been compiled and seven GMPEs were selected. The assessment was performed on the basis of 100 synthetic seismic sub-catalogs with duration 10,000 years each. The hazard curves were calculated for the nodes of 0.25°×0.25° grid and the hazard maps were created in terms of PGA, PGV and seismic intensity for rock sites. Preliminary sensitivity analysis was performed to determine the importance of the input parameters and the level of uncertainty introduced by the parameters. The developed framework and the results of PSHA provide a benchmark for the comprehensive seismic hazard and seismic risk analysis and up-to-date seismic hazard maps for the Kingdom of Saudi Arabia. [ABSTRACT FROM AUTHOR]

We present a new approach to assessment of regional seismic hazard, which accounts for observed (instrumentally recorded and historic) earthquakes, as well as for seismic events simulated for a significantly longer period of time than that of observations. We apply this approach to probabilistic seismic hazard analysis (PSHA) for the Tibet–Himalayan region. The large magnitude synthetic events, which are consistent with the geophysical and geodetic data, together with the observed earthquakes are employed for the Monte-Carlo PSHA. Earthquake scenarios for hazard assessment are generated stochastically to sample the magnitude and spatial distribution of seismicity, as well as the distribution of ground motion for each seismic event. The peak ground acceleration values, which are estimated for the return period of 475 yr, show that the hazard level associated with large events in the Tibet–Himalayan region significantly increases if the long record of simulated seismicity is considered in the PSHA. The magnitude and the source location of the 2008 Wenchuan M = 7.9 earthquake are among the range of those described by the seismic source model accepted in our analysis. We analyze the relationship between the ground motion data obtained in the earthquake's epicentral area and the obtained PSHA estimations using a deaggregation technique. The proposed approach provides a better understanding of ground shaking due to possible large-magnitude events and could be useful for risk assessment, earthquake engineering purposes, and emergency planning. [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]

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]

A gallium(I) carbenoid derived from redox-active diimine 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) in complexes with molybdenum may serve either as a neutral [(dpp-bian)Ga:] or an anionic [(dpp-bian)Ga:]- two-electron donor depending on the electronic state of the transition metal. [ABSTRACT FROM AUTHOR]

The complete lists of vector hyperbolic equations on the sphere that have integrable third-order vector isotropic and anisotropic symmetries are presented. Several new integrable hyperbolic vector models are found. By their integrability, we mean the existence of vector Bäcklund transformations depending on a parameter. For all new equations, such transformations are constructed. [ABSTRACT FROM AUTHOR]

We analyzed the within-earthquake correlation (peak ground acceleration PGA and velocity PGV) in Japan by taking into account local geological conditions. The database includes more than 23,700 records (K-NET and the KiK-net networks) from 84 events (M 4.2–7.4) occurring in 1999–2011. The correlation structure was investigated for residuals obtained using two recently developed ground-motion models for Japan. We have shown that the level of within-earthquake correlation may vary significantly depending on site classes, general geological conditions and earthquake magnitude. The results of the analysis are in general agreement with the findings obtained recently for Taiwan (Sokolov et al. in Bull Earthq Eng 10(5):1401–1429, 2012 . doi: 10.1007/s10518-012-9368-5 ). The high level of ground-motion correlation reflects the presence of a non-random component in the residuals that may be caused by the joint influence of surface soil and thick sediments, and this influence depends on the earthquake magnitude. Therefore, a single generalized model of within-earthquake correlation across geologically heterogeneous regions may not be adequate. The application of empirical correction factors, which may be a function of earthquake magnitude, source-to-site distance, site class, and average shear-wave velocity for a given station, allows for effective reduction in the level of within-earthquake correlation. [ABSTRACT FROM AUTHOR]

We analysed the within-earthquake correlation of ground motion using the strong-motion records accumulated by the TSMIP (Taiwan Strong Motion Instrumentation Program) network in Taiwan during 1993-2009. Two ground-motion prediction equations, which were recently developed for peak ground acceleration (PGA) in the region and based on moment and local magnitude and hypocentral distance, were used for the calculation and analysis of ground-motion residuals. We also used the database containing shear-wave velocity data averaged for the top 30 m of the soil column (Vs30) for the TSMIP stations. We showed that the within-earthquake correlation may vary significantly depending on site classes, gross geological features of the area, and magnitude of earthquakes, records of which dominate the analysed dataset. On the one hand, there is a prominent correspondence between the within-earthquake correlation of PGA residuals and spatial correlation of Vs30 values, which was estimated for particular geological structures (e.g., sedimentary filled basins and large plain areas). On the other hand, the high level of ground-motion correlation (or significant non-random component of residuals) may be caused by the joint influence of soft surface soil and thick sediments and by the path or azimuthal effects. The point-source approximation of extended fault and neglected hanging- and foot-wall effects may also result in non-random residuals. The application of empirical correction factors, which consider the magnitude of earthquakes, source-to-site distance and Vs30 value for given stations, allows for the effective reduction in the level of within-earthquake correlation, as well as the within-earthquake standard deviation. The results of the analysis may be used in practical estimates of seismic hazard, damage and loss for spatially distributed structures (portfolios, lifelines) in Taiwan, as well in other regions with similar geological characteristics. [ABSTRACT FROM AUTHOR]

Abstract: We find a general solution to the unique 7th order ODE admitting a ten-dimensional group of contact symmetries. The integral curves of this ODE are rational contact curves in which give rise to rational plane curves of degree six. The moduli space of these curves is a real form of the homogeneous space . [Copyright &y& Elsevier]

Abstract: The earthquake risk on Romania is one of the highest in Europe, and seismic hazard for almost half of the territory of Romania is determined by the Vrancea seismic region, which is situated beneath the southern Carpathian Arc. The region is characterized by a high rate of occurrence of large earthquakes in a narrow focal volume at depth from 70 to 160km. Besides the Vrancea area, several zones of shallow seismicity located within and outside the Romanian territory are considered as seismically dangerous. We present the results of probabilistic seismic hazard analysis, which implemented the “logic tree” approach, and which considered both the intermediate-depth and the shallow seismicity. Various available models of seismicity and ground-motion attenuation were used as the alternative variants. Seismic hazard in terms of macroseismic intensities, peak ground acceleration, and response spectra was evaluated for various return periods. Sensitivity study was performed to analyze the impact of variation of input parameters on the hazard results. The uncertainty on hazard estimates may be reduced by better understanding of parameters of the Vrancea source zone and the zones of crustal seismicity. Reduction of uncertainty associated with the ground-motion models is also very important issue for Romania. [Copyright &y& Elsevier]

Given an associative multiplication in matrix algebra compatible with the usual one or, in other words, a linear deformation of the matrix algebra, we construct a solution to the classical Yang-Baxter equation. We also develop a theory of such deformations and construct numerous examples. It turns out that these deformations are in one-to-one correspondence with representations of certain algebraic structures, which we call M-structures. We also describe an important class of M-structures related to the affine Dynkin diagrams of A, D, E-type. These M-structures and their representations are described in terms of quiver representations. [ABSTRACT FROM AUTHOR]

Abstract: The frequency-dependent amplification for rock (NEHRP-class B) sites was studied using earthquake ground-motion database collected in Taiwan during implementation of the Taiwan Strong Motion Instrumentation Program. The database used includes several hundred records from earthquakes of M L 4.0–7.3 occurred between 1993 and 2004. The characteristics of amplification were evaluated using the well-known technique of horizontal-to-vertical Fourier spectral ratio (H/V) of the S-wave phase [Lermo J, Chavez-Garcia FJ. Site effect evaluation using spectral ratios with only one station. Bull Seism Soc Am 1993;83:1574–94]. The study allows us to analyze peculiarities of rock sites amplification in Northern and Eastern Taiwan. It was suggested to divide the NEHRP-class B site amplification into four types based on frequency of maximum amplification and the shape of amplification function. The applicability of the technique was also checked for a few stiff and soft soil sites (NEHRP-classes D and E). [Copyright &y& Elsevier]

Abstract: Unusually strong apparent surface activity of the pair of 2-mercaptoethane sulfonic acid (MES) and 2-aminoethanethiol (AET) in forming a phase-separated ternary self-assembled monolayer (SAM) composed of MES, AET, and 1-dodecanethiol (DDeT) has been investigated with changing the conditions for preparing the SAM by coadsorption of the thiols from an ethanolic solution. When the total concentration of the thiols, c total, is 1×10−3 moldm−3 or higher, the MES–AET pair forms electrostatically stabilized domains from an early stage of the adsorption after the immersion of a gold substrate in the bathing ethanol solution. The total area of the MES–AET domains does not change with time for longer immersion. The adsorption of DDeT is significantly weaker than the MES–AET pair under such conditions, despite the fact that the intrinsic surface activity of DDeT is greater than those of MES and AET. DDeT-rich islands of typically a few nanometer across spread in the SAM and the size and the distribution of the islands are invariant over a week. In contrast, when c total is lower than 0.1×10−3 moldm−3, the adsorptivity of DDeT is stronger than that of the MES–AET pair, and MES and AET initially adsorbed are gradually replaced with DDeT at longer immersion time. This switching of the mode of phase separation with the change in c total suggests the crucial roles of the electrostatic interaction of MES and AET in the course of the formation of the SAM and of the hydrophilic barrier formed on the domains to prevent the replacement by hydrophobic DDeT molecules. [Copyright &y& Elsevier]

Details the efforts to achieve victory in the World War II. Formulation of the thesis of indivisible peace by Moscow, Russia in December 1933; Agreement of the French to sign on mutual assistance with the Soviet Union; Information on territory and population lost by Czechoslovakia under the Munich agreement.

Abstract: The paper presents recent achievements in evaluations of site-dependent seismic hazard in Romania and the capital city of Bucharest caused by the Vrancea focal zone (SE-Carpathians). The zone is characterized by a high rate of occurrence of large earthquakes in a narrow focal volume at depths 60–170km. The database that was used for the hazard evaluation includes parameters of seismicity, ground-motion source scaling and attenuation models (Fourier amplitude spectra), and site-dependent spectral amplification functions. Ground-motion characteristics were evaluated on the basis of several hundred records from more than 120 small magnitude (M 3.5–5) earthquakes occurred in 1996–2001 and a few tens of acceleration records obtained during four large (M 7.4, 7.2, 6.9 and 6.3) earthquakes. The data provide a basis for probabilistic seismic hazard assessment in terms of peak ground acceleration, peak spectral acceleration and MSK intensity using Fourier amplitude spectra for various exceedance probabilities or average return periods. It has been shown that the influence of geological factors plays very important role in distribution of earthquake ground-motion parameters along the territory of Romania. [Copyright &y& Elsevier]

We analyze the ability of different spectral models to describe the frequency content of ground motion during the 1999 Chi–Chi earthquake (MW=7.6, Taiwan) and two large (ML=6.8) aftershocks. The spectral models evaluated include the one-corner model of Brune applied with various key parameters (seismic moment and stress drop), and the two-corner-frequency models proposed for eastern North America [Bull. Seismol. Soc. Am. 83 (1993) 1778] and California [Bull. Seismol. Soc. Am. 90 (2000) 255]. The ground-motion spectra predicted by these spectral models for hypothetical very hard rock site were compared with the Chi–Chi earthquake data obtained on rock (class B) and soft rock or very dense soil (class C) sites. The approach also allows us evaluating the generalized empirical amplification function for class B and C sites in the region.It has been found that, the amplitude spectra of recorded ground acceleration (the mainshock and aftershocks) for frequencies larger than 0.3–0.4 Hz agree with the modelled two-corner-frequency spectra calculated using the model proposed for California. The single-corner-frequency model also provides a good agreement with the observations when using so-called ‘short-period seismic moment’ [Phys. Earth Planet. Interiors 37 (1985) 108] instead of the reported values obtained from long-period waves. The key parameters used in the single-corner model coincide with parameters of subsources evaluated for the complicated mainshock source. Therefore, it is possible to confirm the suggestion that the short-period seismic waves, at least for the thrust earthquakes, are generated mainly from the fracture of small-scale heterogeneities. The use of two-corner-frequency source model for earthquake spectrum that is based on long-period seismic moment value is equivalent, for frequencies larger than 0.3–0.4 Hz, to the use of single-corner-frequency model that is based on the parameters of major subsource. [Copyright &y& Elsevier]

Inhibition of acetylcholinesterase (AChE) versus inhibition and aging of neuropathy target esterase (NTE) by organophosphorus (OP) compounds in vivo can give rise to distinct neurological consequences: acute cholinergic toxicity versus OP compound-induced delayed neurotoxicity (OPIDN). Previous work has shown that the relative potency of an OP compound to react with NTE versus AChE in vitro may predict its capability to produce OPIDN. The present study was conducted to evaluate further the validity of such predictions and to enhance them with quantitative structure-activity relationships (QSAR) using a homologous series of alkyl phenylphosphonates, (RO)C 6 H 5 P(O)ON=CClCH 3 (PhP; R=alkyl). Neuropathic potential of PhP was assessed by measuring k i (NTE)/k i (AChE) ratios in vitro and comparing these with ED50 ratios in vivo. Selectivity for NTE increased with rising R-group hydrophobicity. The k i (NTE)/k i (AChE) ratios were 0.42 (methyl), 3.6 (ethyl), 15 (isopropyl), 36 (propyl), 69 (isobutyl), 105 (butyl), and 124 (pentyl). Ratios >1 suggest the potential to produce OPIDN at doses lower than the LD50. Inhibition of NTE and AChE in hen brain in vivo was studied 24 h after im injection of hens with increasing doses of methyl and butyl derivatives. Analysis of dose-response curves yielded ED50(AChE)/ED50(NTE) ratios of 0.86 for methyl PhP and 22.1 for butyl PhP. These results predict that the butyl derivative should be more neuropathic than the methyl analogue. Excellent correspondence between in vivo and in vitro predictions of neuropathic potential indicate that valid predictive QSAR models may be based on the in vitro approach. Adoption of this system would result in reducing experimental animal use, lowering costs, accelerating data production, and enabling standardization of a biochemically based risk assessment of the neuropathic potential of OP compounds. [ABSTRACT FROM AUTHOR]

In the Taiwan region, the empirical spectral models for estimating ground motion parameters were obtained recently on the basis of recordings of small to moderate (5.0≤ML≤6.5) earthquakes. A large collection of acceleration records from the recent ML 7.3 (MW 7.6) Chi-Chi earthquake (20 September, 1999) makes it possible to test the applicability of the established relationships in the case of larger events. The comparison of ground motion parameters (peak accelerations and response spectra), which were calculated using the stochastic approach based on the modeled Fourier amplitude spectra, and the observed data demonstrates that the models may be successfully used for ground motion prediction for earthquakes of magnitudes up to ML=6.8–7.0 and hypocentral depth more than 10 km. To satisfy to the peculiarities of ground motion during shallow (depth less than 10 km) and larger (ML>7.0) events, the models were revised. [Copyright &y& Elsevier]

In the Taiwan region, the empirical spectral models for estimating ground-motion parameters were obtained recently on the basis of recordings of small to moderate (5.0≤ML≤6.5) earthquakes. A large collection of acceleration records from the ML=7.3 Chi-Chi earthquake (21 September, 1999) makes it possible to test the applicability of the established relationships in the case of larger events. The comparison of ground-motion parameters (Fourier amplitude spectra, peak accelerations and response spectra), which were calculated using the models, and the observed data demonstrates that the models could provide an accurate prediction for the case of the Chi-Chi earthquake and the largest aftershocks. However, there are some peculiarities in the ground-motion frequency content and attenuation that, most probably, are caused by the features of the rupture process of the large shallow earthquake source. [Copyright &y& Elsevier]

• Bulky aluminum hydrides. • Acenaphthene-1,2-diimine ligands. Insertion of carbon dioxide. The reactions of [(ArBIG-bian)Al(H) 2 Li(THF) 4 ] (1) (ArBIG-bian = 1,2-bis[(2,6-dibenzhydryl-4-methylphenyl)imino]acenaphthene, THF = tetrahydrofuran), [(dpp-bian)Al(H) 2 Li(THF) 3 ] (2) (dpp-bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) and [(dpp-bian)AlH(Cl)][Na(DME) 3 ] (3) (DME = 1,2-dimethoxyethane) with carbon dioxide proceed with its insertion into Al–H bonds and afford [(ArBIG-bian)Al{μ-OC(H)O} 2 Li(THF) 2 ] (4), [{(dpp-bian)AlOC(H)OLi(THF) 3 } 2 μ-O] (5) and [(dpp-bian)Al(µ-O){µ-OC(H)O}Al(dpp-bian)][Na(DME) 3 ] (6) respectively. Complex 5 is a product of thermally induced transformation of bis-formate intermediate [(dpp-bian)Al{μ-OC(H)O} 2 Li(THF) n ] (5a), which can be isolated from the reaction of 2 and CO 2 at ambient temperature. Newly prepared compounds were characterized by IR and NMR spectroscopy; molecular structures of products 4, 5 and 6 were established by single-crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

The analysis of the problems examined in this article is based on studies carried out in 1992 and in some cases in 1993 (see the Comments section [at the end of this article]) by the Sociological and Sociopsychological Center of the Russian Academy of Management, the Institute of Comprehensive Social Research, the All-Russian Center for Social Research, the Sociopsychological Center of the Lomonosov Moscow State University, the Independent Association of Social Research, and a number of other sociological services and scientific institutes. All the investigations are representative, with samples for Russia as a whole or, in some cases, for Moscow. The specificity of the phenomena analyzed made it necessary to use studies conducted in earlier years and to draw on historical and other material in addition to sociological and psychological findings. [ABSTRACT FROM AUTHOR]

Every routine shortage in our country is accompanied by an upsurge of mass belief in something or other. At the very peak of the detergent shortage, the country agonized in the expectation that, well, Gdlian and Ivanov would arrest the entire Politburo, take back the plundered billions, and hand them out to ordinary workers. Then, when medicines began to be missing from the pharmacies, Chumak and Kashpirov began to work wonders with us on the television, wholesale. The panic over salt and vegetable oil was accompanied by UFO landings everywhere. Now, poultry and bread have become scarce. We have begun to believe in market programs. [ABSTRACT FROM AUTHOR]

Two regional ground-motion models are available at present for western Saudi Arabia, a region that is characterized by considerable seismic activity due to the spreading in the Red Sea and continental volcanism. The first model was created by Sokolov and Zahran (Arab J Geosci 11:38, 2018) using the stochastic simulation technique (Boore in Pure Appl Geoph 160(3):635–676, 2003) and it was reported in tabular form for moment magnitudes (M) from 5 to 7. The second model was developed by Kiuchi et al. (Bull Seismol Soc Am 109:2722–2737, 2019) as mathematical expression (empirical ground motion prediction equation, GMPE) on the basis of records from regional earthquakes with local magnitudes from ML 3 to 5.4. In this work, we first construct a GMPE using stochastic simulation data. This stochastic GMPE considers magnitude, distance and stress drop as input parameters. Second, we compare these two independently developed regional ground-motion models and employ a scheme for the modification of the empirical GMPE up to M 7.5 using the stochastic GMPE as the reference model. The revised GMPEs presented here provide regional ground motion models (PGA and spectral amplitudes at natural periods 0.2 s and 1.0 s) that may be used in logic tree scheme for assessment of seismic hazard in western Saudi Arabia. [ABSTRACT FROM AUTHOR]

Probabilistic seismic hazard assessment (PSHA) is widely used in earthquake engineering practice and seismic risk management. However, the results of classical point-wise PSHA contain no information about simultaneous ground motions during one earthquake at different sites located within a defined area. Such multiple-site estimations are very useful for assessment of damage and corresponding losses in densely populated areas and for analysis of lifeline performance. Recently Wenzel and Sokolov (2018) introduced parameter that describes probability that specified ground motion level (e.g. design ground motion) will be exceeded at least once in at least fraction of the reference area during specified period of time. The parameter was called as Fraction of Areal Exceedance (FAE). The estimations of FAE may be used both for the risk management decisions and for selection of appropriate design ground motion. This article describes the sensitivity analysis of FAE that includes consideration of various input characteristics that may influence on the results. • Design ground motion may be exceeded in the considered area during particular earthquake. • We characterize the phenomenon by Fraction of Areal Exceedance (FAE). • The parameter provides a clue for the extent of potential damage. • The parameter may be useful for selection of appropriate design ground motion. • Sensitivity analysis of the parameter was performed. [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]

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]

Abstract Understanding of lithosphere dynamics, tectonic stress localization, earthquake occurrences, and seismic hazards has significantly advanced during the last decades. Meanwhile, despite the major advancements in geophysical sciences, yet we do not see a decline in earthquake disaster impacts and losses. Although earthquake disasters are mainly associated with significant vulnerability of society, comprehensive seismic hazards assessments and earthquake forecasting could contribute to preventive measures aimed to reduce impacts of earthquakes. Modeling of lithosphere dynamics and earthquake simulations coupled with a seismic hazard analysis can provide a better assessment of potential ground shaking due to earthquakes. Here we present a block-and-fault dynamics (BAFD) model, which simulates earthquakes due to lithosphere dynamics and allows for studying the influence of fault network properties and regional movements on seismic patterns. The model's performance is analyzed in terms of reproduction of basic features of the observed seismicity such as the frequency-magnitude relationship, clustering of earthquakes, occurrences of large events, fault slip rates, and earthquake mechanisms. Several studies related to the application of the BAFD model to the following earthquake-prone regions are reviewed: the southeastern Carpathians, Caucasus, the western India, Tibet-Himalaya, and the Sunda Arc. We examine then a new approach to seismic hazard analysis, which is based on instrumentally recorded, historical and BAFD-simulated earthquakes, and analyze how earthquake modeling can assist in hazard assessment. Finally, we discuss perspectives in modeling of earthquake occurrences and improvements in hazard assessment. Highlights • Dynamic modeling of lithospheric blocks and faults is examined. • Simulated large events in several seismic hazard-prone regions are reviewed. • Hazard assessment utilizes recorded, historical, and simulated earthquakes. [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]

Abstract: A method for recovery of valuable metals from a spent nickel–metal hydride battery has been investigated. Mischmetal–nickel alloy (MmNi5), which acts as an anode active material, was separated from an electrode scrap mixture using a sedimentation process. The separated MmNi5 contains rare earth metals (14.5mass% Ce, 10.8mass% La, 4.5mass% Nd) and transition metals (49.2mass% Ni, 9.8mass% Co, 4.7mass% Mn). CCl4 gas was employed as a chlorination roasting agent to prevent the formation of rare earth oxychlorides. When MmNi5 was chlorinated at 673K, it was decomposed into rare earth chlorides and nickel alloy. The chlorinated sample was subsequently leached with distilled water to recover these materials. The leaching yields of La, Ce, and Nd reached 96.3, 77.4, and 80.1mass%, respectively, and 85.7mass% of the Ni and 87.1mass% of the Co could be recovered as Ni–Co alloy. The relatively lower recovery ratios of Ce and Nd can be attributed to the stability of Ce and Nd oxychlorides. When the chlorination temperature reached 773K, MmNi5 was completely chlorinated. At 973K and higher, a greenish precipitate was also observed in the low-temperature zone of the reaction tube. Because the vapor pressures of rare earth and transition metal chlorides differ from each other, the transition metal chlorides can be separated by vaporization. Their yields reached 94.6% (La), 95.3% (Ce), and 94.9% (Nd) in the chlorinated residue. [Copyright &y& Elsevier]

Dimebon belongs to a fast-growing group of 'old' drugs that were suggested to be effective for therapy of pathological conditions different from their original targets. Following initial reports of successful Phase II clinical trials for mild-to-moderate Alzheimer's and Huntington's diseases, effects of Dimebon on various neurodegenerative conditions were investigated both in follow-up clinical trials and in various model systems. Although results of Phase III clinical trials carried out so far were disappointing, there is growing body of evidence that this drug can affect neuronal physiology in a way that would be beneficial at particular stages of development of certain types of neurodegeneration. To reveal what molecular and cellular pathological processes might be affected by Dimebon, we tested the ability of this drug to ameliorate pathology in model systems recapitulating particular pathogenic mechanisms involved in the development and progression of neurodegenerative diseases. Here we assessed the ability of Dimebon to modify several prominent features of tauopathies using transgenic tauP301S mice as a model. Chronic treatment with Dimebon was found to partially protect against the progressive decline in motor function and accumulation of tau-positive dystrophic neurons characteristic of tauP301S mice. Similar results were obtained with two further γ-carbolines structurally similar to Dimebon. Our data suggest that Dimebon and Dimebon-like compounds might be considered as drugs possessing disease-modifying activity for diseases with prominent tau pathology. [ABSTRACT FROM AUTHOR]

Abstract: Rapamycin contributes to the expansion of regulatory T cells (Tregs) in vitro. We investigated CD4+CD25highCD127low Treg level dynamics as well as the major parameters of cell immunity and sCD25 and highly sensitive C-reactive protein (hsCRP) concentrations in the blood of patients after coronary stenting (CS) with sirolimus (rapamycin)-eluting stents (SES; n = 43). The relation between initial Treg values and the severity of coronary atherosclerosis was observed. Treg and sCD25 levels were increased 1 month after CS versus baseline values and versus data in the control group (coronary angiography [CA], n = 20). A positive correlation between Treg and sCD25 levels was reported, whereas no relation was observed with the length of SES implanted. HsCRP level was increased during the first 7 days and returned to baseline values 1 month after CS/CA. Treg content is lower in patients with multivessel CAD. Elevated levels of Tregs and sCD25 after SES implantation might occur because of the immunomodulating effect of rapamycin. [Copyright &y& Elsevier]

The thermal conductivity of NaLaS2-CaS system solid solutions has been experimentally investigated in the temperature range 80-450K. It is determined the heat transfer mechanisms in the studied system. In all of the solid solutions studied, lattice thermal conductivity prevails. The composition dependence of thermal conductivity coefficient has been determined within the range of studied system. The pattern of thermal conductivity change under composition change is caused by defect structure of NaLaS2-CaS system solid solutions. [ABSTRACT FROM AUTHOR]

The August 17, 1999 Kocaeli earthquake ruptured the earth’s surface along 145 km and produced a magnitude ofM w=7.4. As expected for such an event Modified Mercalli intensities of typically IX and X in the vicinity of the fault were determined. Yet the observed accelerations at the five near-fault sites remained amazingly small with horizontal PGA values of 0.14 g to 0.4 g. We attempt to resolve the enigma by modeling surface ground motion with a finite-difference algorithm, utilizing two different rupture and slip histories derived from the strong-motion observations and ‘translate’ the computed horizontal motion in intensity values. We can show that (a) in a given simple crustal velocity model different slip distributions result in significantly different ground motion distributions in the vicinity of the fault even though both slip distributions fit the observed accelerometer data quite well. (b) Both slip distributions ‘project’ high ground motion into areas adjacent to the fault where no accelerometer was located. (c) Both slip distributions are not fully compatible with observed intensity observations around the fault, although this could be partly attributed to the lack of knowledge regarding to the crustal structure. In the light of our results it would thus be misleading if the few strong-motion observations around the Kocaeli earthquake fault were taken as typical or representative for the entire area and for potential future events. [ABSTRACT FROM AUTHOR]