No abstract

External electric field effects on absorption, fluorescence, and fluorescence decay of p-HBDI that is a model compound of the chromophore of GFP have been examined in a poly(methyl methacrylate) film. The electroabsorption spectrum is similar in shape to the first derivative of the absorption spectrum, which results from the difference in molecular polarizability between the ground state and the Franck-Condon excited state. The electrophotoluminescence spectrum is dominated by the corresponding fluorescence spectrum, indicating the enhancement of the fluorescence intensity in the presence of external electric fields. The direct measurements of the electric field effect on the fluorescence decay profile suggest that the field-induced deceleration of the nonradiative process contributes to the increase in the fluorescence intensity in the presence of electric fields.

Betalains, comprising violet betacyanins and yellow betaxanthins, are pigments found in plants belonging to the order Caryophyllales. In this study, we induced the accumulation of betalains in ornamental lisianthus (Eustoma grandiflorum) by genetic engineering. Three betalain biosynthetic genes encoding CYP76AD1, dihydroxyphenylalanine (DOPA) 4,5-dioxygenase (DOD), and cyclo-DOPA 5-O-glucosyltransferase (5GT) were expressed under the control of the cauliflower mosaic virus (CaMV) 35S promoter in lisianthus, in which anthocyanin pigments are responsible for the pink flower color. During the selection process on hygromycin-containing media, some shoots with red leaves were obtained. However, most red-colored shoots were suppressed root induction and incapable of further growth. Only clone #1 successfully acclimatized and bloomed, producing pinkish-red flowers, with a slightly greater intensity of red color than that in wild-type flowers. T 1 plants derived from clone #1 segregated into five typical flower color phenotypes: wine red, bright pink, pale pink, pale yellow, and salmon pink. Among these, line #1-1 showed high expression levels of all three transgenes and exhibited a novel wine-red flower color. In the flower petals of line #1-1, abundant betacyanins and lowlevel betaxanthins were coexistent with anthocyanins. In other lines, differences in the relative accumulation of betalain and anthocyanin pigments resulted in flower color variations, as described above. Thus, this study is the first to successfully produce novel flower color varieties in ornamental plants by controlling betalain accumulation through genetic engineering.

No abstract

Until now, no formula has been derived for computing the acoustic parameters of the transmitting and receiving systems in the actual piezoelectric telephone handset of small size and light weight. The lack of such a formula was a significant hindrance to the design of the handset. In this paper, estimation of these parameters is made possible by the application of the nonlinear optimization technique. In this optimization problem, convergence is extremely slow since there is a magnitude difference of about 1010 among the parameters. Hence, for each parameter, a hypothetical maximum and minimum are assumed so that the problem is replaced with a hypothetical conditional optimization problem. By means of the change of variables, the variable ranges of all the parameters are aligned. At the same time, the problem is transformed back to the optimization problem without constraints so that the convergence is accelerated. Since the performance function is constructed in which all the measured characteristics of the transmitting and receiving sensitivities under different measurement conditions are used as esimating information, the resultant optimization problem is of a significant size. The simulation characteristics computed based on the obtained estimation values agreed well with the measured characteristics. This implies that the estimated value derived by the present method is useful in actual design of the handset.