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SummaryPrevious research unveiled that the overexpression of catalytically promiscuous CYP81A cytochrome P450s underlies the multiple-herbicide resistance (MHR) in a Californian population of Echinochloa phyllopogon. However, it does not fully accommodate the resistance to diverse herbicides in MHR E. phyllopogon although the genetic inheritance of MHR was suggested as under a single gene control.We investigated the high-level resistance to diclofop-methyl in MHR E. phyllopogon. Detailed diclofop-methyl metabolism was analyzed, followed by gene expression study and functional characterization of P450 genes. The generality of the MHR mechanism was investigated using another MHR line.The MHR line rapidly produced two distinct hydroxylated-diclofop-acid, only one of which was the major metabolite produced by CYP81A12/21. Gene expression study identified the genetically linked overexpression of a novel gene CYP709C69 with CYP81A12/21 in the MHR line. The gene conferred diclofop-methyl resistance in plants and produced another hydroxylated-diclofop-acid in yeast. The activity was observed in some CYP709C in plants. Unlike the broad substrate-specificity in CYP81As, CYP709C69 showed narrow substrate-specificity. The overexpression of the CYP81A and CYP709C69 was also observed in another MHR line.The present findings establish a novel concept that genetically-linked simultaneous overexpression of herbicide-metabolizing genes enhances and broadens the profile of metabolic resistance in weeds.

Variable voltage variable frequency (VVVF) inverter systems have been utilized for propulsion of electric railway cars, and it has been essential to reduce electromagnetic noise caused by those inverter systems. One of the EMI issues is AM radio noise which should be reduced in order to guarantee the service for railway passengers. However, detailed countermeasures of noise reduction and circuit simulation methods to estimate the noise current focusing on the AM radio frequency band have not been reported yet. This paper focuses on AM radio noise and its current, and suggests a detailed noise reduction method targeting a VVVF inverter on an electric railway car. The simulated and measured currents are compared, and the effectiveness of the simulation model is verified under the conditions of with and without the countermeasure.

Global warming is predicted to have significant impacts not only on crop productivity but also on crop quality, leading to economic loss. In the present study, focusing on grain quality of rice in Japan, we assessed the impact of global warming on the occurrence of low quality rice grain called ‘chalky rice grain’, and the incurred economic loss. Using 10 future climate scenarios and a simulation model to estimate the occurrence of chalky rice grain, we showed that global warming will double the occurrence of chalky rice grain by the 2040 s under RCP8.5. This corresponds to one third of paddy rice fields in Japan showing a decrease in grain grade. This would produce an annual economic loss of 401.4 million US$/yr under RCP8.5 in the 2040 s. These results suggest that the development and implementation of national and local adaptation strategies are urgently needed for rice production in Japan.

Direct AC/AC converters have been investigated for miniaturization, high efficiency and harmonics reduction of mains current. These converters are classified into direct switch AC/AC converter (matrix converter) and PWM rectifier-inverter AC/AC converter in view of each circuit configuration.Firstly, this paper proposes averaged DC link voltage control of direct AC/AC converters, and details of the control method are described. In this method, averaged DC link voltage is derived from two selecting phase-to-phase mains voltages and the duty ratio of these selecting voltages for each modulation period. The averaged DC link voltage is used for the calculation of modulation index at each output phase.Secondly, this paper discusses a compensation method of output voltage error from commutation in case of applying the averaged DC link voltage control. Generally, the output voltage error occurs in direct AC/AC converters from commutation sequence consisting of two or four steps. And the compensation method reduces the error by analyzing commutation pattern created by the averaged DC link voltage control.Finally, experimental results are demonstrated, and it is confirmed that the harmonic distortion of the output current is efficiently reduced with the proposed compensation method.

A newly proposed energy-compensating active control is implemented to reduce the return current noise which is caused by inverter-driven electric car systems. The energy-compensating active control detects the energy charged at the filter capacitor, and reduces the energy and current of the noise frequency component by simple feedback loop incorporated with the conventional motor torque controller. No additional sensors or circuit arrangements are necessary; therefore, the return current can be attenuated effectively without any further cost. The return current with an inverter system is measured using a current probe and an FFT analyzer, and it is shown that the 25-Hz noise current is reduced by up to 10 dB with the control. The results reveal that the low-frequency return current noise can be attenuated with the simple control scheme, which would expectedly reduce the size of filter reactors and capacitors to meet the current limit level of the signaling system's track relays. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 84–91, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20615

The pathophysiological role of endothelin ET(B) receptor-mediated action on systemic and renal hemodynamics and urine formation in deoxYcorticosterone acetate (DOCA)-salt hypertensive rats was investigated. An intravenous bolus injection of a selective ET(B) receptor antagonist, BQ788 (1 mg/kg), produced a significant increase in mean arterial pressure (MAP) of DOCA-salt treated rats, whereas the agent-induced increase in MAP was less marked in normotensive sham rats. Administration of BQ788 caused a significant and sustained reduction in renal blood flow both in DOCA-salt and sham rats. No marked effects were observed on urine formation in both groups. Alternatively, a selective ET(A) receptor antagonist, FR139317 (10 mg/kg), produced a potent hypotensive effect, accompanied by significant renal vasodilation in DOCA-salt hypertensive rats, but these effects were partially reversed by the subsequent administration of BQ788. When renal perfusion pressure was protected from FR139317-induced hypotension by an aortic clamp, significant diuresis and natriuresis were observed, events partially reversed by the subsequent administration of BQ788. Our results indicate that the ET(B) receptor-mediated action tonically functions as a hypotensive and a renal vasodilatory factor and that these effects seem to be up-regulated in DOCA-salt hypertension. We also suggest that the ET(A) receptor blockade in DOCA-salt hypertensive rats unmasks the ET(B) receptor-mediated action which partially contributes to the antihypertensive effect induced by FR139317.

Rats were trained to avoid drinking 0.1 m NaCl solution by one to four pairings of this solution with an i.p. injection of 0.15 m LiCl during restricted periods of fluid access. The number of lickings of NaCl and nonpaired other solutions was measured during the preconditioning control period, after conditioning, and after lesions of various brain regions. The acquired learned aversion was abolished after bilateral lesions of the gustatory cortex, perirhinal cortex posterior to the gustatory cortex, or stria terminalis. Ablations of the frontal cortex had no effect. These results suggest that cortical-amygdalar-hypothalamic connections play a significant role in the retention of a conditioned taste aversion.

Reaction times and perceived intensities for NaCl solutions were measured in sixteen human adults. Stimulus delivery was by means of a circular piece of solution-soaked filter paper held with forceps. The reaction time (T) decreased and the perceived intensity (S) increased with increasing the concentration (C) of NaCl solution applied to a fixed (78.5 mm2) tongue area. The comprehensive relations among T, S and C can be expressed by the following formula; T=a+b/log(C/Co), T=p+q/log(S/So), and logS=mlogC+logn, where a, b, p, q, m, n=constants, and So indicates the perceived intensity at the threshold concentration (Co). Meanwhile, the reaction time decreased and the perceived intensity increased with increasing the stimulated area (A) under a fixed (1.0 M) concentration of NaCl solution. The relations among T, S and A can also be expressed by the following equations; T=a'+b'/log(A/Ao), T=p'+q'/log(S/So), and logS=m'logA+logn', where a', b', p', q', m', n'=constants, and Ao indicates the threshold size of stimulated area.