Plant J.

Benzoxazinoids are major compounds involved in chemical defence in grasses. These toxins are stored in the vacuole as glucosides. Two glucosyltransferases, BX8 and BX9, that catalyse this last step of benzoxazinoid biosynthesis have been isolated via functional cloning. No close relative of these maize genes was found among the known glucosyltransferases. The enzymes display a very high degree of substrate specificity. DIMBOA, the major benzoxazinoid in young maize, is the preferred substrate. Both genes are highly expressed in young maize seedlings, the developmental stage with the highest activity of benzoxazinoid biosynthesis. Bx8 is included in the cluster of DIMBOA biosynthesis genes located on the short arm of chromosome 4. Hence, the gene cluster comprises three different enzymatic functions and a complete set of genes for the biosynthesis of DIBOA glucoside. Bx9 mapped to chromosome 1. Expression of Bx8 and Bx9 in Arabidopsis corroborated the potency of the enzymes in detoxification of their substrates. This capacity might have implications for allelopathic interactions

Algorithm-based continuous pulse duration tuning and performance control of a mode-locked laser diode

A control algorithm is presented that addresses the stability issues inherent to the operation of monolithic mode-locked laser diodes. It enables a continuous pulse duration tuning without any onset of Q-switching instabilities. A demonstration of the algorithm performance is presented for two radically different laser diode geometries and continuous pulse duration tuning between 0.5 ps to 2.2 ps and 1.2 ps to 10.2 ps is achieved. With practical applications in mind, this algorithm also facilitates control over performance parameters such as output power and wavelength during pulse duration tuning. The developed algorithm enables the user to harness the operational flexibility from such a laser with 'push-button' simplicity. (C) 2012 Optical Society of AmericaPublisher PDFPeer reviewe

Two glucosyltransferases are involved in detoxification of benzoxazinoids in maize

Benzoxazinoids are major compounds involved in chemical defence in grasses. These toxins are stored in the vacuole as glucosides. Two glucosyltransferases, BX8 and BX9, that catalyse this last step of benzoxazinoid biosynthesis have been isolated via functional cloning. No close relative of these maize genes was found among the known glucosyltransferases. The enzymes display a very high degree of substrate specificity. DIMBOA, the major benzoxazinoid in young maize, is the preferred substrate. Both genes are highly expressed in young maize seedlings, the developmental stage with the highest activity of benzoxazinoid biosynthesis. Bx8 is included in the cluster of DIMBOA biosynthesis genes located on the short arm of chromosome 4. Hence, the gene cluster comprises three different enzymatic functions and a complete set of genes for the biosynthesis of DIBOA glucoside. Bx9 mapped to chromosome 1. Expression of Bx8 and Bx9 in Arabidopsis corroborated the potency of the enzymes in detoxification of their substrates. This capacity might have implications for allelopathic interactions

Diaphragmatic eventration

In general, diaphragmatic eventration (DE) is defined as abnormal elevation of all (or a portion of) an attenuated (but otherwise intact) diaphragmatic leaf [1]. The term “eventration” was used first by Becklard in 1829 (through Petit probably described the condition in 1970). Bingham described plication of the diaphragm in 1954 [2, 3]. Based on etiopathogenesis, DE may be classified as “congenital” or “acquired” even though the clinical features and principles of management are similar for both forms