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Summary: Trichomes that originate from plant aerial epidermis act as mechanical and chemical barriers against herbivores. Although several regulators have recently been identified, the regulatory pathway underlying multicellular trichome formation remains largely unknown in tomato.Here, we report a novel HD‐ZIP IV transcription factor, Lanata (Ln), a missense mutation which caused the hairy phenotype. Biochemical analyses demonstrate that Ln separately interacts with two trichome regulators, Woolly (Wo) and Hair (H). Genetic and molecular evidence demonstrates that Ln directly regulates the expression of H.The interaction between Ln and Wo can increase trichome density by enhancing the expression of SlCycB2 and SlCycB3, which we previously showed are involved in tomato trichome formation.Furthermore, SlCycB2 represses the transactivation of the SlCycB3 gene by Ln and vice versa. Our findings provide new insights into the novel regulatory network controlling multicellular trichome formation in tomato. [ABSTRACT FROM AUTHOR]

Detailed oxidation course of H‐initiated degradation of CH3CHCO has been researched taking advantage of quantum chemical methods. Geometrical optimizations of reactants, intermediates, transition states, and products were operated at the B3LYP/6‐31++G(d,p) level. Single‐point energy computations were implemented at the CCSD(T)/cc‐pVTZ//B3LYP/6‐311++G(d,p) level. The results state clearly that the H association was more energetically beneficial than the abstraction of H, and the dominant pathway is generation of P1 (CH3CH2 + CO). Rate constants of H association reactions are computed by making use of Rice–Ramsperger–Kassel–Marcus (RRKM) program at 200–3000 K. Specifically, the total rate constant of H association reactions is 6.47 × 10−13 cm3 molecule−1 s−1 at 298 K, which is consistent with the experimental results (6.58 × 10−13 cm3 molecule−1 s−1). This research offers a thorough comprehending of the reaction mechanism involved in H‐initiated atmospheric degradation of CH3CHCO and might act as a relevant supplemental reference criteria for experimental research. [ABSTRACT FROM AUTHOR]

A comprehensive study on the reaction of H + C3H6 has been conducted in order to clarify the temperature and pressure dependence of product branching. Site‐specific rate of addition of a hydrogen atom to the center carbon is measured by a comparative method for the evolutions of H atoms behind reflected shock waves. The rate constant for the addition to the center carbon can be given by ln(k1‐2/cm3molecule–1s–1) = – (1.67 ± 0.65) × 103 T–1 – (24.18 ± 0.55) for H + C3H6 → n‐C3H7* → products (T = 1065‐1306 K) without pressure dependence for P = 1‐2 bar. Theoretical calculation was conducted to evaluate the pressure dependence of the product branching for the H + C3H6 reaction by using transition‐state theory and RRKM theory based on quantum‐chemical calculations of potential‐energy surfaces. The result indicates that transition of the main reaction channel from addition to the terminal carbon in the low temperature range to the central carbon at moderate pressures (0.001‐10 bar) and elevated temperatures causes S‐shaped non‐Arrhenius temperature dependence of the total reaction rate against T–1; at the transition temperature, a strong pressure dependence was predicted. Our experimental result of k1‐2 agrees very well with the predicted value and available experimental data. The predicted rate constant ratio for the terminal versus nonterminal additions at the high‐pressure limits agrees well with the temperature dependence reported by Manion and Awan for the analogous H + C4H8 reaction. Furthermore, the importance of H‐abstraction reactions at elevated temperatures from three different sites of C3H6 was predicted in this calculation. For kinetic modeling of combustion and pyrolysis of hydrocarbons, we have recommended the rate constants for the 3 abstraction reactions as well as for the production of i‐ and n‐C3H7 radicals by addition reactions at the high‐ and low‐pressure limits over the temperature range of 300‐2000 K. [ABSTRACT FROM AUTHOR]

A comprehensive study on the reaction of H + C3H6 has been conducted in order to clarify the temperature and pressure dependence of product branching. Site‐specific rate of addition of a hydrogen atom to the center carbon is measured by a comparative method for the evolutions of H atoms behind reflected shock waves. The rate constant for the addition to the center carbon can be given by ln(k1‐2/cm3molecule–1s–1) = – (1.67 ± 0.65) × 103 T–1 – (24.18 ± 0.55) for H + C3H6 → n‐C3H7* → products (T = 1065‐1306 K) without pressure dependence for P = 1‐2 bar. Theoretical calculation was conducted to evaluate the pressure dependence of the product branching for the H + C3H6 reaction by using transition‐state theory and RRKM theory based on quantum‐chemical calculations of potential‐energy surfaces. The result indicates that transition of the main reaction channel from addition to the terminal carbon in the low temperature range to the central carbon at moderate pressures (0.001‐10 bar) and elevated temperatures causes S‐shaped non‐Arrhenius temperature dependence of the total reaction rate against T–1; at the transition temperature, a strong pressure dependence was predicted. Our experimental result of k1‐2 agrees very well with the predicted value and available experimental data. The predicted rate constant ratio for the terminal versus nonterminal additions at the high‐pressure limits agrees well with the temperature dependence reported by Manion and Awan for the analogous H + C4H8 reaction. Furthermore, the importance of H‐abstraction reactions at elevated temperatures from three different sites of C3H6 was predicted in this calculation. For kinetic modeling of combustion and pyrolysis of hydrocarbons, we have recommended the rate constants for the 3 abstraction reactions as well as for the production of i‐ and n‐C3H7 radicals by addition reactions at the high‐ and low‐pressure limits over the temperature range of 300‐2000 K. [ABSTRACT FROM AUTHOR]

The Wulong gold orefield is located in the eastern part of the Liaodong Peninsula, and contains the large Sidaogou and Wulong gold deposits, as well as several small gold deposits with a total of >100 tonnes of gold reserves. These deposits are hosted within Paleoproterozoic metamorphic rocks of the Liaohe Group and Mesozoic granitoids, and are structurally controlled by NNE–SSW‐ and NNW–SSE‐trending faults and interlayer fractures. The Sidaogou deposit is characterized by altered‐rock‐type mineralization occurring within interlayer fracture zones, whereas the mineralization in the Wulong deposit occurs as auriferous quartz veins along subsidiary faults. These two types of gold mineralization are representative of the mineralization in the Wulong orefield. The REE contents of quartz and calcite, together with previous studies of fluid inclusions, indicate that the ore‐forming fluids of the Sidaogou deposit were reduced NaCl–H2O–CO2 fluids. Quartz yielded δ18OH2O‐SMOW, δDSMOW, and δ13CCO2 values of +4.7‰ to +6.6‰, −82.2‰ to −79.0‰, and − 13.1‰ to −6.6‰, respectively, and calcite yielded δ13CCO2 and δ18OV‐SMOW values of −2.3‰ to −2.0‰ and + 7.4‰ to +7.9‰, respectively. These results indicate that the ore‐forming fluids of the Sidaogou deposit were derived primarily from magmatic water, and the C was sourced mainly from deep‐seated magma with a minor contribution from sedimentary organic matter. Pyrite crystals have δ34SCDT values of +4.9‰ to +12.9‰, indicating the S source was a combination of the magmatic system and ore‐bearing metamorphic rocks. Pyrite has 208Pb/204Pb ratios of 38.226–38.336, 207Pb/204Pb ratios of 15.606–15.683, and 206Pb/204Pb ratios of 18.345–18.492, suggesting that the Pb in the Sidaogou deposit was derived primarily from the upper crust, with minor input from the mantle. Taking into account previous studies of the Wulong deposit, we propose a metallogenic model for the Wulong gold orefield. Deep‐seated ore‐forming fluids were released from different intrusions hidden below the Wulong orefield for each of the deposits. The ore‐forming fluids moved through the metamorphic rocks of the Gaixian Formation along interlayer fracture zones, where intensive water–wallrock reactions, and episodic temperature and pressure drops resulted in the formation of altered‐rock‐type Sidaogou deposit. The fluids ascended to the Wulong and Sanguliu intrusions along NNE–SSW‐ and NNW–SSE‐trending faults, where temperature and pressure dropping, water–wallrock reactions, and fluid immiscibility generated the vein‐type Wulong deposit. The gold deposits in the Wulong orefield share many similarities with the Linglong‐ and Jiaojia‐type gold deposits in the Jiaodong Peninsula, including geological setting, mineralization style and age, and sources of ore‐forming fluids and metal. [ABSTRACT FROM AUTHOR]

The Yangbishan iron–tungsten deposit, located in the central part of the Jiamusi Massif, Heilongjiang Province, NE China, is the oldest tungsten deposit in NE China to date. Both ore‐forming conditions and mineralisation characteristics indicate that tungsten mineralisation belongs to the skarn type. Petrography, microthermometric measurements and laser Raman spectroscopy of fluid inclusions in quartz grains associated with scheelite indicate that the ore‐forming fluid of the tungsten mineralisation in Yangbishan deposit belonged to the moderate‐temperature NaCl–H2O–CH4±N2 system. Fluid inclusion analyses indicate that ore‐forming fluid experienced decreasing temperatures and fluid degassing, inducing scheelite precipitation. Analysis of C, H and O isotopes of fluid inclusions within scheelite grains show δ13C values varying from −20.7 to −24.9‰, δD from −109.9 to −119.9‰, δ18O from 6.8 to 10.0‰ and δ18OH2O from 8.7 to 11.9‰. These data, together with C, H and O isotope compositions of the quartz associated with scheelite in tungsten ores, imply that ore‐forming fluid was derived dominantly from magma but influenced by organic material (reducing carbon) derived from wall rocks. Sm/Nd ratios of scheelite vary from 0.15 to 0.21, εNd (t = 520 Ma) values from −5.64 to −17.95 (average of −10.21) and TDM2 values from 702 and 2693 Ma (average of 2070 Ma), indicating the ores were sourced from ancient crustal rocks. The compositions of C–H–O–S–Pb and Nd isotopes support the fact that interaction between crust‐derived magma and strata rich in organics played an important role in the tungsten mineralisation of the Yangbishan deposit. [ABSTRACT FROM AUTHOR]

In this study, a cascaded single-phase converter topology is proposed for single-phase microgrid integrated into high-voltage power distribution systems. In this system, the lower single-phase converter works in voltage controlled mode to reduce the harmonic distortions of supply voltage to local critical load. At the same time, the upper single-phase converter is placed in between the main grid and the output of the lower single-phase converter. Alternatively, the upper power cell works in current controlled mode to block the harmonic current pollutions from the local non-linear load. Through collaborative control of the cascaded upper and lower converter, the proposed system can provide active harmonic filtering to both single-phase supply voltage and single-phase grid current, but without any harmonic extractions in the entire process. [ABSTRACT FROM AUTHOR]

Molecular logic gate has been proposed using single‐strand DNA (ssDNA) consisting of basic four nucleobases. In this study, density functional theory and non‐equilibrium Green's function based first principle approach is applied to investigate the electronic transmission characteristics of ssDNA chain. The heavily hydrogen‐doped‐ssDNA (H‐ssDNA) chain is connected with gold electrode to achieve enhanced quantum‐ballistic transmission along 〈1 1 1〉 direction. Logic gates OR, Ex‐OR, NXOR have been implemented using this analytical model of H‐ssDNA device. Enhanced logic properties have been observed for ssDNA after H adsorption due to improved electronic transmission. Dense electron cloud is considered as logic 'high' (1) output in presence of hydrogen molecule and on the contrary sparse cloud indicate logic 'low' (0) in the absence of hydrogen molecule. Device current is significantly increased from 0.2 nA to 2.4 µA (approx.) when ssDNA chain is heavily doped with hydrogen molecule. The current–voltage characteristics confirm the formation of various Boolean logic gate operations. [ABSTRACT FROM AUTHOR]

Four cascaded quasi‐impedance source inverter (qZSI) modules are required for achieving nine‐level output voltage waveform. In case of one module failure, number of levels in output voltage are reduced to seven. This leads to decrease in the output voltage magnitude and increased THD (higher than conventional seven‐level qZSI). This is due to the dominance of unwanted harmonic component introduced in the harmonic spectrum. To restore voltage magnitude and optimize THD performance, novel voltage balancing algorithm is proposed. To validate the control algorithm for off‐grid and grid connected system, simulation results of the multilevel qZSI are discussed in two categories: (i) DC voltage source powered multilevel qZSI for RL load subjected to module failure and (ii) solar powered multilevel qZSI connected to utility grid subjected to module failure and variable solar irradiation. Pre‐fault and post‐fault performance of the system with the proposed control algorithm is discussed for both categories, which validates the effectiveness of the algorithm. Hardware results for proof‐of‐concept are discussed for DC voltage source fed cascaded qZSI connected to RL load during pre‐fault and post‐fault conditions. FPGA Virtex‐5 is used for hardware implementation of the control algorithm. The results validate the improvement in output voltage both quantitatively and qualitatively. [ABSTRACT FROM AUTHOR]

SUMMARY This work concerns robust sensor fault detection observer (SFDO) design for uncertain and disturbed discrete-time Takagi-Sugeno (T-S) systems using H − ∕ H ∞ criterion. The principle of the proposed approach is based on simultaneously minimizing the perturbation effect and maximizing the fault effect on the residual vector. Furthermore, by introducing slack decision matrices and taking advantage of the descriptor formulation, less conservative sufficient conditions are proposed leading to easier linear matrix inequalities (LMIs). Moreover, the proposed (SFDO) design conditions allow dealing with unmeasurable premise variables. Finally, a numerical example and a truck-trailer system model are proposed to illustrate the efficiency of the SFDO design methodology. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The thermal stability of H dopants in ZnO nanorod (NR) array is demonstrated to be greatly enhanced by a H2/Ar mixed plasma treatment compared to a H2 plasma treatment and hence their optoelectronic properties. For all the as-treated samples with the plasma containing H2 plasma, ultraviolet emission and electrical conductivity are enhanced as well as sensitivity and photoresponsivity of UV sensing. Notably, only the H2/Ar-treated samples show high thermal stability of H dopants and enhanced optoelectronic properties after annealing at 300 °C for 1 h, which is attributed to the assistance of Ar plasma. [ABSTRACT FROM AUTHOR]

Recent discoveries of the role of alkane flexibility in determining liquid-crystal behaviour are surveyed. With the impetus for understanding the alkane conformational problem established, recent model dependent 1H NMR work on the topic will be reviewed where progress is made but the need to circumvent models eventually becomes evident. A closer look at the rigid basic units of alkanes will provide the way forward where it is shown that the orientational ordering and anisotropic potentials of these molecules dissolved in liquid crystals scale with each other. Once this relationship is established, a series of works using anisotropic and isotropic 1H NMR spectroscopy to study alkane conformational statistics will be covered, wherein the influence of the gas, isotropic condensed and anisotropic condensed phases will be described. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Developmental states are often associated with high economic growth. Japan, South Korea, China and Brazil are all examples, most of which grew at phenomenal rates. The National Development Plan in South Africa sets out the intention of the South African government to transform the government into a 'capable and developmental state able to intervene to correct our historical inequities ...' However, what the South African government means by the term 'developmental state' is not entirely clear. To help bring some clarity, this paper distinguishes between the East Asian developmental state and the Scandinavian developmentalist welfare state. The paper furthermore draws on Bernard and Boucher's distinction between a 'social investment state' and a 'transfer welfare state.' The former is a more precise description of the Scandinavian developmentalist welfare state. Subsequently, the paper discusses the applicability of the developmental state framework to South Africa. Specifically, it argues that the East Asian model neither is a model that would work in South Africa, nor is it a model that South Africa would wish to apply. South Africa currently resembles more a transfer welfare state than the Scandinavian-Brazilian social investment state. The social investment state, though, is closer to what South Africa needs. [ABSTRACT FROM AUTHOR]

Natural variations in the stable isotope ratios of bioelements in bird feathers are being increasingly used by animal ecologists to investigate different aspects of bird life. However, to ensure reliability of the data, a critical and very delicate aspect is the preparatory phase (cleaning, drying and subsampling) and the proper analysis, mainly in relation to δ2 H and δ18 O, respectively, for the presence of exchangeable Hs and of nitrogen and sulphur in keratin., With respect to determination of the isotope ratios of C, N, O and H, in this work, we compare the cleaning mixture most commonly used in the literature (chloroform : methanol 2 : 1) with diethylether : methanol 2 : 1, which avoids the use of the carcinogenic solvent chloroform. We also compared oven-drying with air-drying of samples, as well as subsampling of feathers by cutting with surgical scissors or cryogenic pulverization. Finally, we investigated whether stable isotope ratios varied along the vane and between the rachis and vane., The different methods compared in the three preparatory stages showed no differences performance-wise and can therefore be used interchangeably. Variability in stable isotope ratios can be considerable, both along the vane and between rachis and vane, which is because their compositions register changes in diet, area and climate. However, in this specific study, when the parts of the feather closest to the calamus were removed, the delta values were clearly more homogeneous. Finally, we demonstrate that a casein with a known δ2 H value, although probably differing from keratin in the number of exchangeable Hs, can be used to normalize the δ2 H values of feathers, although only in the range of values close to that of the reference material. In determining δ18 O, the use of a longer gas chromatography- GC column, its frequent change and the use of a linear equation built with matrix match equivalent reference materials seems to reduce the drift of GC column performance due to the presence of nitrogen and the accumulation of sulphur. [ABSTRACT FROM AUTHOR]

In the context of multidimensional measures of well-being, a key question for policy is whether particular groups have differing priorities and are therefore likely to react differently to given economic or social shocks. We explore this issue by presenting the results of two related analyses that suggest positive answers on both counts. First, we apply reference class weights to unique data on adult capabilities in the UK and show that relative weights vary across some groupings. Furthermore, in some cases, deprivation rankings of groups vary depending on which weights are used. Second, we explore possible behavioural consequences of different weights by examining the extent to which groups respond differently to three economic and social shocks (unemployment, widowhood and ill health). In this case, we find that weights and responses vary noticeably with age and region and sometimes with gender. We conclude that whilst equal weighting may be practically unavoidable when constructing indices of welfare in the absence of information on weights, their estimation from survey or experimental data is likely to be justified and may change views about policy needs or efficacy. [ABSTRACT FROM AUTHOR]

Transition State Theory, with Wigner tunneling correction, was employed to determine the thermal rate coefficients for the first excited state of the H+ + LiH reaction using the potential energy surface calculated and fitted by Martinazzo et al. [Martinazzo et al., J Chem Phys 2003, 119, 11241]. The calculated thermal rate coefficients, in the temperature range of 500–1,000 K, are near to the value of 10-9 cm3 s-1 and tend to a constant value (10-8 cm3 s-1) at lower temperatures (200 K). These results support the recent investigation of Bulut et al. that showed the TRC to be nearly independent of temperature. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

The H-bonded complexes formed from interaction between NH2NO (NA) and H2O2 (HP) have been investigated by using B3LYP and MP2 methods with a wide range of basis sets. We found six H-bonded complexes in which three of them have cyclic structure. Calculations carried out at various levels show that the seven-membered cyclic structure with O···HO and O···HN hydrogen bonding interactions is the most stable complex. The large binding energy obtained for A1 complex probably results from a more linear arrangement of the O···H&bond;N and O&bond;H···OH-bonds in the seven-membered structure A1. The natural bond orbital (NBO) analysis and the Bader's quantum theory of atoms in molecules have been used to elucidate the interaction characteristics of the NA-HP complexes. The NBO results reveal that the charge transfer energy corresponds to the H-bond interactions for A1 complex is grater than other complexes. The electrostatic nature of H-bond interactions is predicted from QTAIM analysis. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

We have studied H2 adsorption on C3H3V organometallic compound using density functional method at B3LYP/LanL2Dz level of theory. It was found that H2 molecule dissociates and adsorbed in dihydride form on this organometallic compound. Potential energy surface for H2 dissociation process was obtained and different properties such as HOMO–LUMO gap, dipole moment, interaction energies between different molecules and atoms, vibrational frequencies, and atomic charges during the dissociation process were studied. It was found that the C3H3V(H2) structure is most stable at H&bond;V&bond;H angle of 66.3°. Many-body analysis was also carried out to determine the two-body energies, three-body energies, relaxation energy, and binding energy of the structures for each point on the potential surface. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

Sodium hydroxide and its derivatives are used as pulping reagents, wherein the spent NaOH is recovered in salt form and reused. In this study, use of low concentration NaOH (1–5%) in pretreatment of corn stover and hybrid poplar was investigated. It was done with the understanding that NaOH can be recovered. One of the main objectives in this study is to explore the potential of H2O2 with NaOH for pretreatment of high lignin substrate such as hybrid poplar. Pretreatment time has not been optimized in this study but held constant at 24 h. Corn stover, after treatment with NaOH under moderate conditions, attains near quantitative glucan digestibility. On the other hand, hybrid poplar requires treatment at higher temperature and NaOH concentration to attain acceptable level of digestibility. Supplementation of hydrogen peroxide in the pretreatment significantly raises delignification and digestibility of hybrid poplar. It was also helpful in retaining the carbohydrates in the treated solids. Retention of hemicellulose after pretreatment provides a significant economic benefit as it eliminates the need for detoxifying hemicellulose sugars. As the residual xylan remaining after pretreatment is an impediment to enzymatic digestion of glucan, supplementation of xylanase has significantly increased the digestibility of glucan as well as xylan of the treated hybrid poplar. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [ABSTRACT FROM AUTHOR]

The reaction of H radical with C2H5CN has been studied using various quantum chemistry methods. The geometries were optimized at the B3LYP/6-311+G(d,p) and B3LYP/6-311++G(2d,2p) levels. The single-point energies were calculated using G3 and BMC-CCSD methods based on B3LYP/6-311++G(2d,2p) geometries. Four mechanisms were investigated, namely, hydrogen abstraction, C-addition/elimination, N-addition/elimination and substitution. The kinetics of this reaction were studied using the transition state theory and multichannel Rice-Ramsperger-Kassel-Marcus methodologies over a wide temperature range of 200–3000 K. The calculated results indicate that C-addition/elimination channel is the most feasible over the whole temperature range. The deactivation of initial adduct C2H5CHN is dominant at lower temperature with bath gas H2 of 760 Torr; whereas C2H5+HCN is the dominant product at higher temperature. Our calculated rate constants are in good agreement with the available experimental data. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 [ABSTRACT FROM AUTHOR]

This study is intended as a continuation of previous experimental and theoretical works on the systems H2O-Rg, H2S-Rg, H2O2-Rg, and H2S2-Rg, where Rg = He, Ne, Ar, Kr, Xe. For the H2O-Rg and H2S-Rg systems, molecular and atomic polarizabilities have been calculated and from them, using phenomenological correlation formulas modeling the dispersion-repulsion (van der Waals) forces, the isotropic interaction parameters have been determined and compared with experimental data from this laboratory. For the H2O2-Rg and H2S2-Rg systems, the molecular polarizabilities have been calculated and used in correlation formulas to predict well depths and positions of van der Waals forces and a comparison made with the corresponding potential energy surfaces calculated in previous works. The approach correctly predicts the interaction parameters, except for H2O and H2O2 with the heavier rare gases. The correlation formulas have been then extended to include an attractive induction contribution accounting for the interaction between the permanent molecular dipole moment and the instantaneous induced atomic dipole moment, to improve the predicted parameters for H2O and H2O2-Ar, Kr and Xe. The agreement with experimental and theoretical data is improved but the predicted data still underestimate the interaction. This is probably due to the presence of a significant non van der Waals contribution to the interaction for the heavier gases, as suggested by analogy with the previously studied water-Rg case. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

In this article we present a characterization of the vibrational spectrum of the H5+ molecule using the correlation function quantum Monte Carlo (CFQMC) method and a genetic algorithm study of the topology of the potential energy surface (PES) used. The vibrational modes associated with the H3+-H2 torsion and stretching possess very flat minima. As a consequence the fundamental frequencies corresponding to these modes are poorly described in the harmonic approximation. In our genetic algorithm study of the PES using Cartesian coordinates we have found some unexpected minima. A careful analysis shows that, in the curvilinear coordinates in which the potential is described, some of these minima have identical coordinates. Nevertheless, they represent nonequivalent molecular geometries. The vibrational frequencies obtained in this work are not in good agreement with available experimental data as well as other computational methods. It shows that our method of detailed analysis of PESs could reveal shortcomings introduced by the use of curvilinear coordinates. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [ABSTRACT FROM AUTHOR]

The q-Integral method, based on the q-Exponential function, has been recently introduced as an alternative approach to calculate the two-electron integrals which appear in ab initio atomic and molecular quantum mechanical calculations. The advantage of this procedure is that the CPU time for calculating of two-electron integrals is substantially reduced when compared with the usual one. The objective of this work is to investigate the accuracy of the q-Integrals as a function of the internuclear distance for molecular systems. To this purpose we employed the q-Integrals to construct the potential energy surface (PES) for the H2 molecule and used the PES to determine the rovibrational levels and spectroscopic constants of the molecule, which are properties very sensitive to the form of the PES. The results obtained are in good agreement with the ones obtained through the standard procedure of calculating the two-electron integrals, implying that the q-Integral method is accurate enough to be used in any molecular quantum mechanical calculation. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [ABSTRACT FROM AUTHOR]

This paper investigates the progressivity of personal income tax in South Africa over the period 1989 to 2003. We use the effective, redistributive and disproportionality measures of progressivity and find that progressivity of the tax system increased over the period 1990 to 1994. However, during the first phase of the reform programmes the results are inconclusive with the Kakwani index (disproportionality measure) showing increased progressivity. The redistributive effect measure, on the other hand, indicates a marginal decline in progressivity. During the second phase of the reform programmes, both techniques suggest a worsening in progressivity. One explanation for the decline in progressivity during the latter period in the analysis is the fact that many more “new” taxpayers entered the tax net (higher income groups in our database) which made the distribution of pre-tax income more unequal thus impacting on progressivity. On the other hand, the disproportionality measure shows a continuous, albeit volatile increase in progressivity over the latter period under investigation. [ABSTRACT FROM AUTHOR]

On the basis of calculations using the density functional theory, we show that C62, a recently synthesized nonclassical fullerene, will presumably undergo dimerization with various isomers at elevated temperatures. This is shown by calculating the dimerization energy and the activation barrier of the dimerization. Eight possible isomers of the dimer were identified, all of which are more stable than the two isolated monomers. The relative stability of various isomers depends upon the kind of C&dbond;C bonds within the four-membered carbon ring involved in the dimerization. In addition, similar calculations were performed for the monomers and dimers of H2&bond;C62 and F2&bond;C62. Six isomers were identified for each of the dimers. Although less pronounced than the case of the C62 dimer, all isomers of the H2&bond;C62 dimer are appreciably more stable than the individual monomers. Although a large steric repulsion due to F atoms significantly reduces the stability of F2&bond;C62 dimer, its two isomers are still more stable than separate monomers. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007 [ABSTRACT FROM AUTHOR]

On the basis of calculations using the density functional theory, we show that C62, a recently synthesized nonclassical fullerene, will presumably undergo dimerization with various isomers at elevated temperatures. This is shown by calculating the dimerization energy and the activation barrier of the dimerization. Eight possible isomers of the dimer were identified, all of which are more stable than the two isolated monomers. The relative stability of various isomers depends upon the kind of C&dbond;C bonds within the four-membered carbon ring involved in the dimerization. In addition, similar calculations were performed for the monomers and dimers of H2&bond;C62 and F2&bond;C62. Six isomers were identified for each of the dimers. Although less pronounced than the case of the C62 dimer, all isomers of the H2&bond;C62 dimer are appreciably more stable than the individual monomers. Although a large steric repulsion due to F atoms significantly reduces the stability of F2&bond;C62 dimer, its two isomers are still more stable than separate monomers. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007 [ABSTRACT FROM AUTHOR]

We used plasma optical emission spectroscopy to investigate the plasma state generated by a radio frequency glow discharge in a monosilane and methane gas mixture. To produce the glow discharge in the gas, we used the source gases separated plasma CVD (SSP-CVD) method proposed in this research, and the conventional diode method. We studied the flow rate ratio and the radio frequency power dependence of the source gases with the plasma optical emission characteristics generated using these methods, and investigated the relationship between the optical emission states and bond states of the elements in films. We found that the optical emission intensities of SiH and CH radicals in the plasma are related to the carbon content and C-Si-H bonds in a-SiC:H films. Furthermore, we found that more H2 radicals than H radicals exist in plasmas generated by the SSP-CVD method than in those generated by the conventional method. We used the above results to study the decomposition process of SiH4-CH4 gases. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(2): 9 –16, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ ecjb.20285 [ABSTRACT FROM AUTHOR]

A molecular dynamics (MD) simulation based on a combined ab initio quantum mechanics/molecular mechanics (QM/MM) method has been performed to investigate the solvation structure and dynamics of H3O+ in water. The QM region is a sphere around the central H3O+ ion, and contains about 6–8 water molecules. It is treated at the Hartree-Fock (HF) level, while the rest of the system is described by means of classical pair potentials. The Eigen complex (H9O4+) is found to be the most prevalent species in the aqueous solution, partly due to the selection scheme of the center of the QM region. The QM/MM results show that the Eigen complex frequently converts back and forth into the Zundel (H5O2+) structure. Besides the three nearest-neighbor water molecules directly hydrogen-bonded to H3O+, other neighbor waters, such as a fourth water molecule which interacts preferentially with the oxygen atom of the hydronium ion, are found occasionally near the ion. Analyses of the water exchange processes and the mean residence times of water molecules in the ion's hydration shell indicate that such next-nearest neighbor water molecules participate in the rearrangement of the hydrogen bond network during fluctuative formation of the Zundel ion and, thus, contribute to the Grotthuss transport of the proton. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006 [ABSTRACT FROM AUTHOR]

Comparison of Hartree–Fock (HF) and Heitler–London (HL) ground-state computations for H2, LiH, Li2, BH, HF, and F2 leads to an approach that is a variational combination of the two approximations. This new HF–HL ab initio method is implemented at three levels. The first level variationally optimizes the linear combination of traditional HF and HL functions. It correctly predicts both molecular formation and dissociation for the above molecules, features not consistently found in either the HF or the HL approximations. The second level introduces valence correlation and the third level inner shells correlation, adapting standard multi-configuration techniques to the HF–HL function. The procedure for both levels has been preliminarily applied to LiH and Li2 and found to yield very encouraging results when compared to experimental data. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [ABSTRACT FROM AUTHOR]

In this article we present the results of a quantum study performed on different models of the active site of methylamine dehydrogenase (MADH). This enzyme catalyzes the oxidation of methylamine to produce formaldehyde and ammonia. During the rate-determinant step of the reaction, a proton is transferred from the methyl group of the substrate to one of the bases of the active site. We performed calculations on three different models of the active site. The number of atoms of the models ranges from 68 to 95. Minimizations and optimizations were performed at the PM3 level of theory. The energies of the optimized structures were then recalculated at the B3LYP 6-31G(d) level. From these energies, we calculated the barriers for H+ transfer toward the putative acceptors of the proton Asp76 and Thr122. By comparing the results of different models against each other, we drew some conclusions about the role of different residues. We found that the H+ transfer from the substrate toward Thr122 requires that this residue be ionized. The estimated barrier for this ionization was found to be >19 kcal/mol. The barrier for H+ transfer from the substrate toward Asp76 is significantly smaller. Our best estimates indicate that this barrier is 9.7 kcal/mol, when the imino group of the substrate is unprotonated and 7.7 kcal/mol when it is protonated. We thoroughly discussed the agreement and disagreement of these values with the results reported in previous theoretical and experimental studies. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [ABSTRACT FROM AUTHOR]

A comparative study of adsorption of H atoms and H2 molecules on Pd3Cu, Cu4, and Pd4 clusters has been performed through density functional calculations, using the hybrid B3LYP exchange‐correlation functional as implemented in the Gaussian98 program. For Pd atoms the relativistic small‐core effective core potential LANL and LANL2DZ basis set was used and for hydrogen a 6‐31G** basis set was used. The main emphasis is set in the reaction behavior of the different clusters with hydrogen atoms and molecules. We find that full geometry optimization does not appreciably change the metal cluster geometry either for certain reaction modes or the H and H2 capture parameters, but increases the number of reactive sites of the metal clusters. Also, we found that there is charge transfer competition between H and Cu atoms, which drastically diminishes H2 adsorption energy, related to the Pd cluster observed value. Edges and threefold sites are the principal hydrogen adsorption sites. Hydrogen has a great mobility over the metal clusters for different minima, especially when Cu is present; many initial pathways end in the same adsorption site. The observed hydrogen adsorption and binding energies are well reproduced by the calculations. Also, the adsorption mechanisms were determined. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [ABSTRACT FROM AUTHOR]

The cytoplasmic tail of the H,K-ATPase β-subunit contains a putative tyrosine-based motif that directs the β-subunit's basolateral sorting when it is expressed in Madin-Darby Canine Kidney (MDCK) cells. When expressed in LLC-PK1 cells, however, the β-subunit is localized to the apical membrane. Several proteins that contain tyrosine-based motifs, including the low-density lipoprotein and transferrin receptors, show a similar sorting ‘defect’ when expressed in LLC-PK1 cells. For low-density lipoprotein and transferrin receptors, this behavior is due to the differential expression of the μ1B subunit of the AP-1B clathrin adaptor complex. μ1B is expressed by MDCK cells, but not LLC-PK1 cells, and transfection of μ1B into LLC-PK1 cells restores basolateral localization of low-density lipoprotein and transferrin receptors. For the β-subunit, however, μ1B expression in LLC-PK1 cells does not induce its basolateral expression. We found that the β-subunit interacts with both μ1B and μ1A in vitro and in vivo. The capacity to participate in a μ1B interaction therefore is not sufficient to program the β-subunit's basolateral localization in MDCK cells. Our data suggest that the H,K-ATPase β-subunit's basolateral sorting signal is either masked in certain epithelial cells, or requires an interaction with sorting machinery other than AP-1B for delivery to the basolateral plasma membrane. [ABSTRACT FROM AUTHOR]

Contents I. Introduction 000 II. Symptoms of aluminium toxicity 000 III. Calcium – aluminium interactions 000 IV. The role of electrical properties of the plasma membrane in calcium–aluminium interactions 000 V. Oxidative stress 000 VI. Callose 000 VII. Cytoskeleton 000 VIII. Conclusions 000 Acknowledgements 000 References 000 Summary This review is concentrating on the role of aluminium (Al)-calcium (Ca) interactions in Al toxicity syndrome in plants. Disruption of cytoplasmic Ca2+ homeostasis has been suggested as a primary trigger of Al toxicity. Aluminium causes an increase in cytosolic Ca2+ activity, potentially disrupting numerous biochemical and physiological processes, including those involved in the root growth. The source of Ca2+ for the increase in cytosolic Ca2+ activity under Al exposure is partly extracellular (likely to be due to the Al-resistant portion of the flux through depolarization-activated Ca2+ channels and fluxes through Ca2+ -permeable nonselective cation channels in the plasma membrane) as well as intracellular (increased cytosolic Ca2+ activity enhances the activity of Ca2+ release channels in the tonoplast and the endoplasmic reticulum membrane). The effect on increased cytosolic Ca2+ activity of possible Al-related inhibition of the plasma membrane and endo-membrane Ca2+ -ATPases and Ca2+ exchangers (CaX) that sequester Ca2+ out of the cytosol is insufficiently documented at present. The relationship between Al toxicity, cytoplasmic Ca2+ homeostasis and cytoplasmic pH needs to be elucidated. Technical improvements that would allow measurements of cytosolic Ca2+ activity within the short time after exposure to Al (seconds or shorter) are eagerly awaited. [ABSTRACT FROM AUTHOR]

Summary Calcium is a ubiquitous intracellular signal responsible for controlling numerous cellular processes in both plants and animals. As an example, Ca2+ has been shown to be a second messenger in the signal transduction pathways by which stomatal guard cells respond to external stimuli. Regulated increases in the cytosolic concentration of free calcium ions ([Ca2+]cyt) in guard cells have been observed to be a common intermediate in many of the pathways leading to either opening or closing of the stomatal pore. This observation has prompted investigations into how specificity is encoded in the Ca2+ signal. It has been suggested that the key to generating stimulus-specific calcium signatures lies in the ability to access differentially the cellular machinery controlling calcium influx and release from intracellular stores. Several important components of the calcium-based signalling pathways have been identified in guard cells including cADPR, phospholipase C–InsP3, InsP6 and H2O2. These data suggest that the pathways for intracellular mobilization of Ca2+ are evolutionarily conserved between plants and animals. Abbreviations ABA, abscisic acid; [Ca2+]cyt, cytosolic free calcium concentration; [Ca2+]ext, external calcium concentration; IK,in; inward-rectifying K+ currents; InsP3, inositol-1,4,5-trisphosphate; InsP6, inositol hexakisphosphate; PLC, phospholipase C; PLD, phospholipase D; PA, phosphatidic acid; H2O2, hydrogen peroxide; AAPK, ABA-activated serine-threonine protein kinase; cADPR, cyclic adenosine 5′-diphosphoribose; U73122, 1-(6-{[17â-3-methoxyestra-1,3,5(10)-trien-17-yl]amino}hexyl)-1H-pyrrole-2, 5-dione; RyR; ryanodine receptor; CICR; calcium-induced calcium-release; ICa, inward calcium current. [ABSTRACT FROM AUTHOR]

A new differential substrate integrated waveguide (SIW) antenna with good common‐mode (CM) suppression and high gain is presented. The designed antenna uses an H‐shaped slot backed by SIW cavity and is differentially excited by two microstrip feedlines from two opposite sides of the cavity. The measured differential impedance bandwidth of the proposed antenna is 10.19–11.03 GHz with CM suppression below 2 dB. The designed differential antenna exhibits a high gain of 8.7 dBi with a good front‐to‐back ratio of 21 dB. [ABSTRACT FROM AUTHOR]

A steady state concentration of HSNO is obtained using a gaseous mixture of 1% NO and 0.1% H2S in Ne by supersonic expansion into a cavity through a pulsed valve at 25 °C. [ABSTRACT FROM AUTHOR]

Flash vacuum pyrolysis of MeOS(O)2N3 (caution: potentially hazardous and explosive) results in the formation of HNSO2 in the gas phase. [ABSTRACT FROM AUTHOR]

Single crystals of the title amidozincate of several centimeters in dimensions are grown under ammonothermal conditions in the cold temperature zone of an autoclave using Zn powder and CsNH2 in a 1:2 molar ratio (stainless steel autoclave, 523→≈423 K, 155 MPa, 12 h). [ABSTRACT FROM AUTHOR]

Polycrystalline Ho2W3O12 is prepared by calcination of stoichiometric amounts of Ho2O3 and WO3 in air (1100 °C, 10 h) with different cooling treatments (850 °C plus furnace cooling or 1100 °C plus quenching in H2O) to probe the relationship between phase formation and preparative conditions. [ABSTRACT FROM AUTHOR]

The first catalytic asymmetric aminotrifluoromethylation of alkenes by using Togni′s reagent (II) has been developed. [ABSTRACT FROM AUTHOR]

Ln(BH4)3 (Ln: La, Ce) is synthesized from mixtures of LnCl3 and LiBH4 in toluene (25 °C, 72 h). [ABSTRACT FROM AUTHOR]

Li3BO3 is prepared by ball milling of an equimolar mixture of LiH and LiBO2 followed by vacuum heating of the pelletized material (600 °C, 2 h). [ABSTRACT FROM AUTHOR]

The title perhydridopolysilathianes are prepared by transsilylation and condensation of HSiCl3·2Py with a five-fold stoichiometric excess of gaseous Tms2S and Py (Schlenk vessel at reduced pressure, 55 °C, 4 d) and subsequent calcination (200 °C, vacuum, 2 h). [ABSTRACT FROM AUTHOR]

Review: 262 refs. [ABSTRACT FROM AUTHOR]

Review: 306 refs. [ABSTRACT FROM AUTHOR]

SinH2n+2 (n ≤ 19) is synthesized by irradiation of thin SiH4 films deposited on a cold (5.5 K) Rh-coated Ag wafer with 5 keV electrons (8-60 min) under ultra-high vacuum conditions. [ABSTRACT FROM AUTHOR]

Review: 143 refs. [ABSTRACT FROM AUTHOR]

Energetic and structural stability of Al2B2H2n (n = 0-6) clusters is investigated by DFT calculations and a stochastic search algorithm. [ABSTRACT FROM AUTHOR]

Compounds (IV) and (V) are characterized by single crystal XRD and UV/VIS spectroscopy. [ABSTRACT FROM AUTHOR]

Four stable two-dimensional boron hydride sheets (C2/m, Pbcm, Cmmm, and Pmmn) are identified by DFT calculations and global minimum search with the particle-swarm optimization method. [ABSTRACT FROM AUTHOR]