•  6
    We report the design and characterization of a CMOS pixel direct charge sensor, Topmetal-II-, fabricated in a standard 0.35 μm CMOS Integrated Circuit process. The sensor utilizes exposed metal patches on top of each pixel to directly collect charge. Each pixel contains a low-noise charge-sensitive preamplifier to establish the analog signal and a discriminator with tunable threshold to generate hits. The analog signal from each pixel is accessible through time-shared multiplexing over the entir…Read more
  •  6
    Different profiles of carcinogen exposure in Chinese compared with US cigarette smokers
    with N. L. Benowitz, Q. Gan, M. L. Goniewicz, W. Lu, J. Xu, Jacob P., and S. Glantz
    © 2015, BMJ Publishing Group. All rights reserved.Background Differences in carcinogen exposure from different cigarette products could contribute to differences in smoking-associated cancer incidence among Chinese compared with US smokers. Methods Urine concentrations of metabolites of nicotine, the tobacco-specific nitrosamine 4--1--1-butanol, and polycyclic aromatic hydrocarbon metabolites were compared in 238 Chinese and 203 US daily smokers. Results Comparing Chinese versus US smokers, dail…Read more
  •  4
    A second-generation expression system for tyrosine-sulfated proteins and its application in crop protection
    with B. Schwessinger, T. L. Ellinghaus, L. J. G. Chan, T. Wei, Joe A., N. Thomas, R. Pruitt, P. D. Adams, M. S. Chern, C. J. Petzold, C. C. Liu, and Ronald P. C.
    Posttranslational modification of proteins and peptides is important for diverse biological processes in plants and animals. The paucity of heterologous expression systems for PTMs and the technical challenges associated with chemical synthesis of these modified proteins has limited detailed molecular characterization and therapeutic applications. Here we describe an optimized system for expression of tyrosine-sulfated proteins in Escherichia coli and its application in a bio-based crop protecti…Read more