Publications by authors named "Shiqian Zhu"

We present the results of a comprehensive model for the electric noise simulation of a kind of nano-optoelectronics device: AIGaAs/GaAs long-wavelength quantum well infrared photodetectors (LW-QWIPs) in dark conditions by assuming a three-dimensional carrier transport in the barriers where the electrical field are obtained in a self-consistent way. This model takes into account all the fundamental mechanisms involved in the device detection process. The electrical field distribution, dark currents, electrical noise are carefully calculated and analyzed.

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Background: The Atlantic Wood Industries Superfund site on the Elizabeth River (ER) in Portsmouth, Virginia, is contaminated with polycyclic aromatic hydrocarbons (PAHs) derived from creosote. Embryos and larvae of ER killifish (Fundulus heteroclitus) are refractory to the induction of enzymes regulated by the aryl hydrocarbon receptor including cytochrome P4501A (CYP1A) and are resistant to PAH-induced lethality and teratogenicity. However, adult ER killifish show a greater prevalence of hepatic and pancreatic tumors compared with those from reference sites.

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Sediment contaminated with polycyclic aromatic hydrocarbons (PAHs) from a Superfund site on the Elizabeth River (ER) in Portsmouth, VA, is teratogenic to embryonic killifish (Fundulus heteroclitus) from reference sites. However, embryos born to a population of ER killifish are resistant to PAH-induced teratogenicity. Mechanisms underlying the resistance are unclear; however, ER killifish are refractory to induction of metabolic enzyme cytochrome P4501A (CYP1A), at the level of mRNA, protein and activity.

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A method based on ultra-performance liquid chromatography mass spectrometry (UPLC-MS) applying atmospheric pressure chemical ionization in the positive ion mode is developed for the determination of coenzyme Q10 (CoQ10) in rat urine. The assay involves the extraction of crude urine, fast liquid chromatography on a Waters Acquity UPLC BEH C18 column (1.7 microm, 1.

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A sensitive and fast method was developed to quantitate the carcinogenic polycyclic aromatic hydrocarbon benzo[a]pyrene (BaP) and eight of its oxidized metabolites by ultra-performance liquid chromatography (UPLC) coupling with mass spectrometry (MS). The UPLC method, using an acetonitrile:water gradient as a mobile phase, provided baseline separation of the BaP metabolites including three BaP diones. Linearity of detection was in the range of 0.

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Normal operation of oil well platforms results in the discharge of produced formation water (PFW). The expression of CYP1A, CYP2M1- and 2K1-like proteins was examined for use as possible biomarkers of PFW exposure. A pilot study on the Northwest Shelf of Australia had indicated that PFW contamination possibly contributes to induction of CYP1A-like proteins in Gold-Spotted Trevally (Carangoides fulvoguttatus).

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The mechanisms of teratogenic effects of ethanol in Japanese medaka embryogenesis were investigated by testing the hypothesis that ethanol or its metabolite ameliorates the expression of ethanol metabolizing enzymes. We have previously demonstrated that ethanol is unable to alter the expression pattern of alcohol dehydrogenase (ADH) mRNA, the first enzyme of ethanol metabolism, in medaka embryos during development. We, therefore, extended our investigation to aldehyde dehydrogenase (ALDH) system, the next enzyme of alcohol metabolic pathway.

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Normal operation of oil well platforms results in the discharge of "produced formation water" (PFW). The expression of CYP1A, CYP2M1- and 2K1-like proteins was examined for use as possible biomarkers of PFW exposure. A pilot study at the Harriet A production platform, on the Northwest Shelf of Australia, had indicated that PFW contamination possibly contributes to induction of CYP1A- and 2K1/2M1-like proteins in Gold-Spotted Trevally (Carangoides fulvoguttatus).

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Water-soluble fullerene (nC60) has been shown to induce lipid peroxidation (LPO) in brain of juvenile largemouth bass (LMB, Micropterus salmoides) [Oberdörster, E., 2004. Manufactured nanomaterials (fullerenes, c60) induce oxidative stress in brain of juvenile largemouth bass.

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