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ABSTRACT An interleaved half-bridge converter is presented for high input voltage application. The features of the proposed converter are zero voltage switching (ZVS) turn-on for all active switches, ripple current reduction at output side, load current sharing and load voltage regulation. Two half-bridge converters connected in series and two split capacitors are used to limit the voltage stress of each power switch at one-half of input DC bus voltage. Thus, active switches with low voltage stress can be used at high input voltage application. On the other hand, the output sides of two half-bridge converters are connected in parallel to share the load current and reduce the current stresses of the secondary windings and the rectifier diodes. Since two half-bridge converters are operated with interleaved pulse-width modulation (PWM), the output ripple current can partially cancel each other such that the resultant ripple current at output side is reduced and the size of output inductors can be reduced. In each half-bridge converter, asymmetrical PWM scheme is used to regulate the output voltage. Based on the resonant behavior by the output capacitance of MOSFETs and the leakage inductance (or external inductance) of transformers, active switches can be turned on at ZVS during the transition interval. Thus, the switching losses of power MOSFETs are reduced. The proposed converter can be applied for high input voltage applications such as three-phase 380-V utility system. Finally, experiments based on a laboratory prototype with 960-W rated power are provided to demonstrate the performance of proposed converter. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

CCN family protein 2 (CCN2), also known as connective tissue growth factor, is a secreting protein that modulates multiple cellular events. We previously demonstrated the metastasis-suppressive effect of CCN2 in lung cancer cells. In this study, we investigate the role of CCN2 in anoikis, a form of programmed cell death that is critical in suppressing cancer metastasis. CCN2 binds to the epidermal growth factor receptor (EGFR) and triggers ubiquitination by inhibiting the formation of the β-pix/Cbl complex, resulting in the degradation of EGFR. Binding of CCN2 to EGFR suppresses the phosphorylation of c-Src and extracellular signal-regulated kinase but increases the expression of death-associated protein kinase, which leads to anoikis. Overall, our findings provide evidence validating the use of CCN2 as an anti-metastatic therapy in lung cancer patients, and prospect a potential therapeutic synergy between CCN2 and the anti-EGFR antibody for the treatment of lung cancer. [ABSTRACT FROM AUTHOR]

A new soft switching DC/DC converter for high-input voltage and medium-power applications is presented in this study to achieve zero-voltage switching (ZVS) turn-on for all power switches, implement load current sharing, reduce the voltage stress of switches at Vin/2 and decrease current rating of the rectifier diodes and the output inductors. Three three-level ZVS DC/DC circuits with the same active switches are adopted in order to reduce the current rating of the rectifier diodes and output filter inductors for high-input voltage and high-load current applications. Three centre-tapped rectifiers are connected in parallel at the secondary side such that the current rating of the transformer windings, rectifier diodes and output filter inductors are reduced and have only one diode conduction loss in the forward current path. Phase-shift pulse-width modulation scheme is used to control four power switches and regulate the output voltage. Based on the resonant behaviour by the output capacitance of active switches and the leakage inductance (or external inductance) at the transition interval, power switches are turned on at ZVS. Finally, experiments with 1 kW prototype are provided to verify the effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]

A parallel soft-switching DC-DC converter with fewer switch count is presented to achieve zero-voltage switching (ZVS), load current sharing and partially output ripple current cancellation. Two buck-type converters are connected in parallel to achieve load current sharing. Only two MOSFETs are used in the proposed converter instead of four switches in a conventional parallel ZVS forward converter. Therefore the proposed converter has fewer active switches. Current-doubler rectifiers are used in the output side in order to achieve partially ripple current cancellation. Therefore the current ripple on output capacitor is decreased and the size of the output choke and output capacitor are reduced. An active snubber is connected between two power transformers to absorb the energy stored in the leakage and magnetising inductances of transformers, to limit voltage stresses across switches, and to achieve ZVS turn-on for all switches. The ZVS turn-on is implemented in the transition interval of two complementary switches such that the switching losses and thermal stresses on semiconductors are reduced. Operation principle, circuit analysis and design example are discussed in detail. Finally, experimental results for a 360 W (12 V/30 A) prototype were presented to verify the effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]