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Reactive oxygen species (ROS) are well known to be involved in oncogene-mediated cellular transformation. However, the regulatory mechanisms underlying ROS generation in oncogene-transformed cells are unclear. In the present study, we found that oncogenic K-Ras induces ROS generation through activation of NADPH oxidase 1 (NOX1), which is a critical regulator for the K-Ras-induced cellular transformation. NOX1 was activated by K-Ras-dependent translocation of p47 phox , a subunit of NOX1 to plasma membrane. Of note, PKCd, when it was activated by PDPK1, directly bound to the SH3-N domain of p47 phox and catalyzed the phosphorylation on Ser348 and Ser473 residues of p47 phox C-terminal in a K-Ras-dependent manner, finally leading to its membrane translocation. Notably, oncogenic K-Ras activated all MAPKs (JNK, ERK and p38); however, only p38 was involved in p47 phox -NOX1-dependent ROS generation and consequent transformation. Importantly, K-Ras-induced activation of p38 led to an activation of PDPK1, which then signals through PKCd, p47 phox and NOX1. In agreement with the mechanism, inhibition of p38, PDPK1, PKCd, p47 phox or NOX1 effectively blocked K-Ras-induced ROS generation, anchorage-independent colony formation and tumor formation. Taken together, our findings demonstrated that oncogenic K-Ras activates the signaling cascade p38/ PDPK1/PKCd/p47 phox /NOX1 for ROS generation and consequent malignant cellular transformation.

A loop-type ground antenna formed by connecting a capacitor between two ground points is described. The resonant frequency of the ground loop is conveniently controlled by changing the capacitance. The proposed loop-type radiator is excited by conventional shorting line loop feeding that may include an inductor. A loop type ground antenna is designed for Bluetooth and Wi-Fi applications.

An innovative antenna radiation method for exciting a dipole-type radiation mode in the ground plane of mobile devices is proposed. This method is based on a capacitively loaded slot placed at the centre of the ground plane. The ground plane is 50 × 15 mm in length and width, respectively, which is the size typically used in USB dongles and headsets. The −10 dB impedance bandwidth is 12.9% at 2.4 GHz, fully covering the WiMax, Wi-Fi and Bluetooth frequency bands.

A loop-type ground antenna with wide-band operation is proposed for USB dongle applications. The solution for improving the bandwidth is based on a resonant feeding circuit that includes both an inductor and a capacitor. By choosing an appropriate ratio of the inductance to the capacitance, the impedance bandwidth (VSWR < 2) is 21.8% at 2.2 GHz, sufficient bandwidth to cover both the WCDMA and WiMax frequency bands.

Résumé -Effet de la composition du gaz naturel sur les performances d'un moteur GNCLe Gaz Naturel Comprimé (GNC) est considéré comme un carburant pour véhicule alternatif en raison de ses avantages économiques et environnementaux. Cependant, il est prouvé que la composition variable des gaz naturels produits dans diverses régions du monde affecte les performances et les taux d'émissions des moteurs GNC. Ainsi, l'objectif de cet essai est de corroborer l'effet de la composition du carburant sur la combustion et sur le taux d'émissions des moteurs GNC. Cet essai présente les caractéristiques de combustion globales obtenues en faisant fonctionner un moteur GNC de 2,5 L de quatre cylindres, posé en deuxième monte sur la base d'un moteur diesel à injection directe et équipé d'un dynamomètre. La puissance du moteur, la consommation de carburant spécifique au freinage, la pression de combustion et les émissions ont été mesurées dans des conditions de fonctionnement constantes en pleine charge et en charge partielle. Les résultats de l'expérience ont montré que la composition du GNC a un impact considérable sur les performances du moteur, sur la consommation de carburant et sur la vitesse de combustion. Une corrélation a été suggérée pour mieux comprendre la relation qui existe entre l'indice de Wobbe (IW) et la puissance du moteur. Elle propose une méthode pratique pour estimer la puissance du moteur lorsque la composition des gaz naturels varie. Abstract -Effect of Natural Gas Composition on the Performance of a CNG Engine -Compressed Natural Gas (CNG) is considered an alternative vehicle fuel because of its economical and environmental advantages. However, the varying composition of natural gases produced in different parts of the world is known to affect the performance and emissions of CNG engines. Thus

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