An overlapping communication protocol using improved time-slot leasing for Bluetooth WPANs

In this paper, we propose an overlapping communication protocol using improved time-slot leasing in the Bluetooth WPANS. One or many slave–master–slave communications usually exist in a piconet of the Bluetooth network. A fatal communication bottleneck is incurred in the master node if many slave–master–slave communications are required at the same time. To alleviate the problem, an overlapping communication scheme is presented to allow slave node directly and simultaneously communicates with another slave node to replace with the original slave–master–slave communication works in a piconet. This overlapping communication scheme is based on the improved time-slot leasing (TSL) scheme which modified from the original TSL, while the original TSL scheme only provides the slave-to-slave communication capability. The key contribution of our improved TSL scheme is to offer the overlapping communication capability. With the overlapping communication scheme, we developed an overlapping communication protocol in a Bluetooth WPANs. Finally, simulation results demonstrate that our developed communication protocol achieves the performance improvements on bandwidth utilization, transmission delay time, network congestion, and energy consumption.     

Regulation of ClC-2 Chloride Channel Proteostasis by Molecular Chaperones: Correction of Leukodystrophy-Associated Defect

The ClC-2 channel plays a critical role in maintaining ion homeostasis in the brain and the testis. Loss-of-function mutations in the ClC-2-encoding human CLCN2 gene are linked to the white matter disease leukodystrophy. Clcn2-deficient mice display neuronal myelin vacuolation and testicular degeneration. Leukodystrophy-causing ClC-2 mutant channels are associated with anomalous proteostasis manifesting enhanced endoplasmic reticulum (ER)-associated degradation. The molecular nature of the ER quality control system for ClC-2 protein remains elusive. In mouse testicular tissues and Leydig cells, we demonstrated that endogenous ClC-2 co-existed in the same protein complex with the molecular chaperones heat shock protein 90β (Hsp90β) and heat shock cognate protein (Hsc70), as well as the associated co-chaperones Hsp70/Hsp90 organizing protein (HOP), activator of Hsp90 ATPase homolog 1 (Aha1), and FK506-binding protein 8 (FKBP8). Further biochemical analyses revealed that the Hsp90β-Hsc70 chaperone/co-chaperone system promoted mouse and human ClC-2 protein biogenesis. FKBP8 additionally facilitated membrane trafficking of ClC-2 channels. Interestingly, treatment with the Hsp90-targeting small molecule 17-allylamino-17-demethoxygeldanamycin (17-AAG) substantially boosted ClC-2 protein expression. Also, 17-AAG effectively increased both total and cell surface protein levels of leukodystrophy-causing loss-of-function ClC-2 mutant channels. Our findings highlight the therapeutic potential of 17-AAG in correcting anomalous ClC-2 proteostasis associated with leukodystrophy.     

Design and modeling of electromagnetic actuator in mems-based valveless impedance pump

This study models and optimizes the electromagnetic actuator in an MEMS-based valveless impedance pump. The actuator comprises an electroplated permanent magnet mounted on a flexible PDMS diaphragm and electroplated Cu coils located on a glass substrate. In optimizing the design of the actuator, the objective is to maximize the output flow rate of the micropump while maintaining the mechanical integrity of its constituent parts. The study commences by developing optimized theoretical models for each of the components within the actuator, namely the diaphragm, the magnet, and the micro-coils. The theoretical models are then verified numerically using FEA software. The magnitude of the magnetic force acting on the flexible diaphragm is calculated using Ansoft/Maxwell3D FEA software. The simulation results obtained by ANSYS FEA software for the diaphragm deflection are found to be in good agreement with the theoretical predictions. In general, the results show that the desired diaphragm deflection of 15 μm can be obtained by passing a current of 0.6–0.7 A through the micro-coil to produce a compression force of 11 μN. The valveless micro impedance pump proposed in this study is easily fabricated and is readily integrated with existing biomedical chips due to its plane structure. The results of this study provide a valuable contribution to the ongoing development of Lab-on-a Chip systems.