Methylamine treatment changes the allocation of carbohydrate to roots in rice plants

Methylamine (MA), an ammonia analogue, has been used to investigate ammonia uptake. This compound competes with ammonia to be taken up and also inhibits the nitrate assimilation pathway. However, the effect of MA on plant growth is unknown. In this paper, we describe the responses of the rice plant to MA. The growth of MA-treated plants was inhibited in the aerial parts and stimulated in the roots. MA-treatment also induced a decrease of starch and hexose in shoots whereas hexose, sucrose and starch contents are increased in MA-treated roots. These results indicate that MA can change the mass allocation of biomass to the roots. The properties of MA suggest that a plant alters its growth via a change in the distribution of carbohydrate in resposes to the nitrogen status.     

Upconversion luminescence of Er3+ in transparent SiO2—PbF2—ErF3 glass ceramics

Oxyfluoride glasses with the composition 50SiO2 · 50PbF2 · xErF3 (x=4 and 5) by molar ratio were developed. Transparent glass ceramics were obtained by heat-treating the 50SiO2 · 50PbF2 · xErF3 glasses at the first crystallization temperatures. X-ray diffraction analysis of the transparent glass ceramics revealed that fluorite type -PbF2:Er3+ solid solution regions of about 13.0 nm in diameter are precipitated in the glass matrix. The formation of this -PbF2:Er3+ solid solution was also supported by Eu3+ fluorescence spectra which were measured on specimens in which Eu substituted for Er. Under 800 nm laser excitation, the Er3+ upconversion luminescence of 50SiO2 · 50PbF2 · xErF3 glasses was barely detectable, but the 50SiO2 · 50PbF2 · xErF3 glass ceramics gave Er3+ upconversion luminescence at a very high efficiency. The reason for the highly efficient Er3+ upconversion luminescence in the 50SiO2 · 50PbF2 · xErF3 glass ceramics can be explained in terms of the very small multiphonon relaxation rates that are anticipated from consideration of the Eu3+ emission spectra.     

A level set based topology optimization method using the discretized signed distance function as the design variables

This paper deals with a new topology optimization method based on the level set method. In the proposed method, the discretized signed distance function, a kind of level set function, is used as the design variables, and these are then updated using their sensitivities. The signed distance characteristic of the design variables are maintained by performing a re-initialization at every update during the iterated optimization procedure. In this paper, a minimum mean compliance problem and a compliant mechanism design problem are formulated based on the level set method. In the formulations of these design problems, a perimeter constraint is imposed to overcome the ill-posedness of the structural optimization problem. The sensitivity analysis for the above structural optimization problems is conducted based on the adjoint variable method. The augmented Lagrangian method is incorporated to deal with multiple constraints. Finally, several numerical examples that include multiple constraints are provided to confirm the validity of the method, and it is shown that appropriate optimal structures are obtained.     

Sensorless control strategy for salient-pole PMSM based on extended EMF in rotating reference frame

This paper presents a novel sensorless control strategy for a salient-pole permanent-magnet synchronous motor (PMSM). A new model of a salient-pole PMSM using an extended electromotive force (EMF) in the rotating reference frame is utilized to estimate both position and speed. The extended EMF is estimated by a least-order observer, and the estimation position error is obtained from the extended EMF. Both estimated position and speed are corrected so that the position error becomes zero. The proposed system is very simple and the design procedure is easy and clear. Several experimental drive tests are demonstrated and the experimental results show the effectiveness of the proposed sensorless control system.     

Electronic state of κ-(BMDT-TTF)2Au(CN)2 studied by NMR and thermoelectric measurements

The electronic state of κ-(BMDT-TTF)₂Au(CN)₂ was investigated by measurements of H-NMR¹-NMR and thermoelectric power. In H-NMR,¹-NMR, the profile of the nuclear relaxation curve changed drastically at 75 K from exponential time-dependence to non-single exponential one reflecting inhomogeneous relaxation. This change evidences a transition in the electronic state at this temperature. However, the longest T₁ below the transition temperature behaves like a Korringa law, suggesting that the low-temperature state is another metallic state. The thermoelectric power shows a strong anomaly around 75 K, being consistent with the NMR results. Above that, the temperature dependence is similar to that found in the κ phase of BEDT-TTF compounds, suggesting a similar Fermi-surface topology. These results suggest that the transition at 75 K is not a conventional metal-to-insulator transition but a metal-to-metal transition.     

Enzyme production activity of Phanerochaete chrysosporium and degradation of pentachlorophenol in a bioreactor

Lignin peroxidase production by a white rot fungus, Phanerochaete chrysosporium, was experimentally investigated using a batch system and a reactor system with various carriers. Immobilization of mycelia cell culture was more effective in promoting cell growth and lignin peroxidase production compared to conventional stationary liquid culture. Biostage carrier, commonly used for biochemical treatment in a fluidized bed disposal system, greatly improved production of lignin peroxidase up to 8.1 U/mL in the batch system. The packed bed reactor system was operated using a repeated batch technique, consisting of alternating growth and production phases, to sustain lignin peroxidase growth and production during the entire experiment period. Steady-state continuous PCP degradation over an extended period was accomplished with a mineralization ratio exceeding 80%. These systems and operation methods are promising techniques for the treatment of hazardous waste.     

Joule heating induced local electrodeposition for microelectronic circuits

A fundamental study is performed for local electrodeposition of copper utilizing thermal potential induced by Joule heating. The feasibility of the process for microelectronic applications is assessed by both experiment and mathematical modeling. The results of the investigation show that (i) a copper wire is coated under conditions of a.c. 50 Hz Joule heating in electrolyte containing 1.0 M CuSO₄ and 0.5m H₂SO₄ with relatively high deposition rate of about 0.4 µm min^–1, (ii) the Joule heating current should be kept below the boiling point of the solution to realize uniform deposition, and (iii) results of calculations by the present model based on one-dimensional heat conduction agree well with experimental results.Nomenclature D diameter of wire (m) - D ₀ initial diameter of wire (m) - F Faraday constant (96 487 C mol¹ ) - g acceleration due to gravity (9.807 m s²) - Gr Grashof number - H thickness of electrodeposit (m) - I current (A) - i ₀ exchange current density (Am^–2) - i _n current density normal to electode (Am^–2) - J current density (I/S) (Am^–2) - L length of wire (m) - M molar concentration of electrolyte (mol dm^–3 or M) - m atomic weight (kg mol^–1) - n number of electrons participating - n unit normal vector to boundary - Nu Nusselt number - Pr Prandtl number - q heat per unit volume (W m^–3) - R universal gas constant (8.314 3 J mol^–1 K^–1) - (r, z) cylindrical coordinate (m) - S cross section of wire (m²) - T temperature (K) - T ₀ fixed temperature at both ends of wire (K) - T _y temperature of electrolyte (K) - t time (s) - x longitudinal coordinate over wire (m) Greek symbols heat transfer coefficient (W m^–2 K^–1 - _a,c anodic (a) and cathodic (c) transfer coefficient - thermal expansion coefficient of solution (K^–1) - specific heat (J kg^–1K^–1) - potential (V) - _e electrode potential (V) - thermal conductivity (W m^–1 K^–1 ) - _y ionic conductivity of electrolyte (^–1m^–1) - _e electronic conductivity of electrode (^–1 m^–1) - kinematic viscosity (m²s^–1) - surface overpotential ( _e – ) (V) - time constant (s) - density (kg m^–3) This work was presented at The 7th International Microelectronics Conference, Yokohama, Japan (1992).     

Initial phoneme versus whole-word criterion to initiate pronunciation: Evidence based on response latency and initial phoneme duration.

Undergraduates participated in 4 speeded naming experiments investigating 2 criteria to initiate articulation–initial phoneme (IP) or whole word (WW). These criteria make different response latency and IP duration predictions for words with regular vs irregular vowel pronunciations (e.g., "pump" vs "pint"). The EP criterion predicts no latency differences but longer IP durations for irregulars, whereas the WW criterion predicts no EP duration differences but longer latencies for irregulars. The latencies and IP durations of words beginning with plosives are measured (a) indirectly by exploiting the conflation of latency and EP duration in the standard naming task and (b) directly by determining when closure begins and ends in the postvocalic naming task (participants say "uuhhh" until responding). Results support both criteria: Response latencies and IP durations are longer for irregular words compared with regular words. (PsycINFO Database Record (c) 2010 APA, all rights reserved)