| 1631. |
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| 1632. |
- Shi, C. L., et al.
(författare)
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Design and power optimization of high-speed pipeline ADC for wideband CDMA applications
- 2001
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Ingår i: Analog Integrated Circuits and Signal Processing. - 0925-1030 .- 1573-1979. ; 26:3, s. 229-238
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a 7-bit 64 MS/s pipeline A/D converter suitable for wideband CDMA applications. Targeting at achieving low power dissipation at high speed, techniques such as digital correction and optimal scaling of capacitor value have been employed. Switched-Opamp technique is used to further reduce power consumption. This ADC is implemented in 0.5 mum standard CMOS process. It operates from a single 3 V supply, and dissipates only 31 mW at 64 MS/s.
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| 1633. |
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| 1634. |
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| 1635. |
- Shi, Xiongjie, et al.
(författare)
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Protein Profiles in Zebrafish (Danio rerio) Embryos Exposed to Perfluorooctane Sulfonate
- 2009
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Ingår i: Toxicological Sciences. - : Oxford University Press. - 1096-6080 .- 1096-0929. ; 110:2, s. 334-340
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Tidskriftsartikel (refereegranskat)abstract
- Perfluorooctane sulfonate (PFOS) is widely distributed and persistent in the environment and in wildlife, and it has the potential for developmental toxicity. However, the molecular mechanisms that lead to these toxic effects are not well known. In the present study, proteomic analysis has been performed to investigate the proteins that are differentially expressed in zebrafish embryos exposed to 0.5 mg/l PFOS until 192 h postfertilization. Two-dimensional electrophoresis coupled with mass spectrometry was employed to detect and identify the protein profiles. The analysis revealed that 69 proteins showed altered expression in the treatment group compared to the control group with either increase or decrease in expression levels (more than twofold difference). Of the 69 spots corresponding to the proteins with altered expression, 38 were selected and subjected to matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (TOF/TOF) analysis; 18 proteins were identified in this analysis. These proteins can be categorized into diverse functional classes such as detoxification, energy metabolism, lipid transport/steroid metabolic process, cell structure, signal transduction, and apoptosis. Overall, proteomic analysis using zebrafish embryos serves as an in vivo model in environmental risk assessment and provides insight into the molecular events in PFOS-induced developmental toxicity.
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| 1636. |
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| 1637. |
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| 1638. |
- Shu, Xiang, et al.
(författare)
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Associations of obesity and circulating insulin and glucose with breast cancer risk : a Mendelian randomization analysis
- 2019
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Ingår i: International Journal of Epidemiology. - : OXFORD UNIV PRESS. - 0300-5771 .- 1464-3685. ; 48:3, s. 795-806
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Tidskriftsartikel (refereegranskat)abstract
- Background: In addition to the established association between general obesity and breast cancer risk, central obesity and circulating fasting insulin and glucose have been linked to the development of this common malignancy. Findings from previous studies, however, have been inconsistent, and the nature of the associations is unclear. Methods: We conducted Mendelian randomization analyses to evaluate the association of breast cancer risk, using genetic instruments, with fasting insulin, fasting glucose, 2-h glucose, body mass index (BMI) and BMI-adjusted waist-hip-ratio (WHRadj BMI). We first confirmed the association of these instruments with type 2 diabetes risk in a large diabetes genome-wide association study consortium. We then investigated their associations with breast cancer risk using individual-level data obtained from 98 842 cases and 83 464 controls of European descent in the Breast Cancer Association Consortium. Results: All sets of instruments were associated with risk of type 2 diabetes. Associations with breast cancer risk were found for genetically predicted fasting insulin [odds ratio (OR) = 1.71 per standard deviation (SD) increase, 95% confidence interval (CI) = 1.26-2.31, p = 5.09 x 10(-4)], 2-h glucose (OR = 1.80 per SD increase, 95% CI = 1.3 0-2.49, p = 4.02 x 10(-4)), BMI (OR = 0.70 per 5-unit increase, 95% CI = 0.65-0.76, p = 5.05 x 10(-19)) and WHRadj BMI (OR = 0.85, 95% CI = 0.79-0.91, p = 9.22 x 10(-6)). Stratified analyses showed that genetically predicted fasting insulin was more closely related to risk of estrogen-receptor [ER]-positive cancer, whereas the associations with instruments of 2h glucose, BMI and WHRadj BMI were consistent regardless of age, menopausal status, estrogen receptor status and family history of breast cancer. Conclusions: We confirmed the previously reported inverse association of genetically predicted BMI with breast cancer risk, and showed a positive association of genetically predicted fasting insulin and 2-h glucose and an inverse association of WHRadj BMI with breast cancer risk. Our study suggests that genetically determined obesity and glucose/insulin-related traits have an important role in the aetiology of breast cancer.
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| 1639. |
- Skote, Martin, et al.
(författare)
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Wall oscillation induced drag reduction of turbulent boundary layers
- 2016
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Ingår i: Springer Proceedings in Physics. - Cham : Springer. - 9783319291291 ; , s. 161-165
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Konferensbidrag (refereegranskat)abstract
- Spanwise oscillation applied on the wall under a turbulent boundary layer flow is investigated using direct numerical simulation. The temporal wall-forcing produces considerable drag reduction over the region where oscillation occurs. The turbulence fluctuations downstream of the oscillations are presented for the first time. Simulations with identical oscillation parameters have been performed at different Reynolds numbers to investigate the effect on the drag reduction. One of the simulations replicates an earlier experiment to test the fidelity of the current simulations. In addition, we present the future work in this area with an integrated experimental and computational investigation to explore the possibility of applying travelling waves (oscillations in both time and space) as the mode of wall motion for active control of near-wall turbulence.
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| 1640. |
- Song, Renfang, et al.
(författare)
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Effects of fifteen PBDE metabolites, DE71, DE79 and TBBPA on steroidogenesis in the H295R cell line
- 2008
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 71:10, s. 1888-1894
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Tidskriftsartikel (refereegranskat)abstract
- Polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA) are brominated flame retardants that are produced in large quantities and are commonly used in construction materials, textiles, and as polymers in electronic equipment. Environmental and human levels of PBDEs have been increasing in the past 30 years, but the toxicity of PBDEs is not fully understood. Studies on their effects are relatively limited, and show that PBDEs are neurotoxins and potential endocrine disrupters. Hydroxylated (OH{single bond}) and methoxylated (MeO{single bond}) PBDEs have also been reported in the adipose tissue, blood and milk of wild animals and humans. In the present study, 15 PBDE metabolites, two BDE mixtures (DE71 and DE79), and TBBPA were studied individually to determine their effects on ten steroidogenic genes, aromatase activity, and concentrations of two steroid hormones (testosterone and 17β-estradiol) in the H295R human adrenocortical carcinoma cell line. Exposure to 0.05 μM 2′-OH-BDE-68 significantly induced the expression of CYP11A, CYP11B2, CYP17, CYP21, 3βHSD2, 17βHSD1, and 17βHSD4, and the expression of StAR was induced by 6-OH-BDE-90 at the three exposure concentrations. Exposure to DE71 and DE79 resulted in dose-dependent trend towards induction, but these effects were not significant. Exposure to 0.5 μM 2-OH-BDE-123 and 2-MeO-BDE-123 resulted in significantly greater aromatase activity. However, none of the compounds affected sex hormone production at the concentrations tested. Generally, OH-BDEs had a much stronger ability to affect steroidogenic gene expression than MeO-BDEs.
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