Browsing by Author "Lin, Chien-Chih"

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PAGE: Parallel Agile Genetic Exploration towards Utmost Performance for Analog Circuit Design
(2013-01-01)
Pan, Po-Cheng
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Chen, Hung-Ming
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Lin, Chien-Chih
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
This paper presents an agile hierarchical synthesis framework for analog circuit. To acknowledge the limitation for a given topology analog circuit, this hierarchical synthesis work proposes a performance exploration technique and a non-uniform-step simulation process. Apart from spec targeted designs, this proposed approach can help to search the solutions better than designers' expectation. A parallel genetic algorithm (PAGE) method is employed for performance exploration. Unlike other evolution-based topology explorations, this is the first method that regards performance constraints as input genome for evolution and resolves the multiple-objective problem with the multiple-population feature. Populations of selected performance are transfered to device variables by re-targeting technique. Based on a normalization of device variable distribution, a probabilistic stochastic simulation significantly reduces the convergence time to find the global optima of circuit performance. Experimental results show that our approach on radio-frequency distributed amplifier (RFDA) and folded cascode operational amplifier (Op-Amp) in different technologies can obtain better runtime and higher quality in analog synthesis.
Structural insights into the histidine-containing phosphotranster protein and receiver domain of sensor histidine kinase suggest a complex model in the two-component regulatory system in Pseudomonas aeruginosa
(2020-09-01)
Chen, Shao-Kang
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Guan, Hong-Hsiang
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Wu, Pei-Hsun
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Lin, Li-Ting
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Wu, Meng-Chun
In Pseudomonas aeruginosa, an important opportunistic pathogen that causes numerous acute and chronic infections, the hybrid two-component system (TCS) regulates the swarming ability and biofilm formation with a multistep phosphorelay, and consists of hybrid-sensor histidine kinase (HK), histidine-containing phosphotransfer protein (Hpt) and response regulator (RR). In this work, two crystal structures of HptB and the receiver domain of HK PA1611 (PA1611REC) of P. aeruginosa have been determined in order to elucidate their interactions for the transfer of the phosphoryl group. The structure of HptB folds into an elongated four-helix bundle - helices alpha 2, alpha 3, alpha 4 and alpha 5, covered by the short N-terminal helix alpha 1. The imidazole side chain of the conserved activesite histidine residue His57, located near the middle of helix alpha 3, protrudes from the bundle and is exposed to solvent. The structure of PA1611REC possesses a conventional (beta/alpha)(5) topology with five-stranded parallel beta-sheets folded in the central region, surrounded by five alpha-helices. The divalent Mg2+ ion is located in the negatively charged active-site cleft and interacts with Asp522, Asp565 and Arg567. The HptB-PA1611REC complex is further modeled to analyze the binding surface and interactions between the two proteins. The model shows a shape complementarity between the convex surface of PA1611REC and the kidney-shaped HptB with fewer residues and a different network involved in interactions compared with other TCS complexes, such as SLN1-R1/YPD1 from Saccharomyces cerevisiae and AHK5(RD)/AHP1 from Arabidopsis thaliana. These structural results provide a better understanding of the TCS in P. aeruginosa and could potentially lead to the discovery of a new treatment for infection.