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Authors = Jianli Zhang

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JIANLI (17) , ZHANG (7455)

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Open AccessArticle New Potential Biomarker for Methasterone Misuse in Human Urine by Liquid Chromatography Quadrupole Time of Flight Mass Spectrometry
Int. J. Mol. Sci. 2016, 17(10), 1628; doi:10.3390/ijms17101628
Received: 11 July 2016 / Revised: 14 September 2016 / Accepted: 19 September 2016 / Published: 24 September 2016
Cited by 1 | Viewed by 599 | PDF Full-text (2162 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this study, methasterone urinary metabolic profiles were investigated by liquid chromatography quadrupole time of flight mass spectrometry (LC-QTOF-MS) in full scan and targeted MS/MS modes with accurate mass measurement. A healthy male volunteer was asked to take the drug and liquid–liquid extraction
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In this study, methasterone urinary metabolic profiles were investigated by liquid chromatography quadrupole time of flight mass spectrometry (LC-QTOF-MS) in full scan and targeted MS/MS modes with accurate mass measurement. A healthy male volunteer was asked to take the drug and liquid–liquid extraction was employed to process urine samples. Chromatographic peaks for potential metabolites were hunted out with the theoretical [M − H] as a target ion in a full scan experiment and actual deprotonated ions were studied in targeted MS/MS experiment. Fifteen metabolites including two new sulfates (S1 and S2), three glucuronide conjugates (G2, G6 and G7), and three free metabolites (M2, M4 and M6) were detected for methasterone. Three metabolites involving G4, G5 and M5 were obtained for the first time in human urine samples. Owing to the absence of helpful fragments to elucidate the steroid ring structure of methasterone phase II metabolites, gas chromatography mass spectrometry (GC-MS) was employed to obtain structural information of the trimethylsilylated phase I metabolite released after enzymatic hydrolysis and the potential structure was inferred using a combined MS method. Metabolite detection times were also analyzed and G2 (18-nor-17β-hydroxymethyl-2α, 17α-dimethyl-androst-13-en-3α-ol-ξ-O-glucuronide) was thought to be new potential biomarker for methasterone misuse which can be detected up to 10 days. Full article
(This article belongs to the Special Issue Metabolomic Technologies in Medicine)
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Open AccessArticle Practical Eco-Design and Eco-Innovation of Consumer Electronics—the Case of Mobile Phones
Challenges 2016, 7(1), 3; doi:10.3390/challe7010003
Received: 3 December 2015 / Revised: 26 January 2016 / Accepted: 2 February 2016 / Published: 15 February 2016
Cited by 3 | Viewed by 1000 | PDF Full-text (1530 KB) | HTML Full-text | XML Full-text
Abstract
Annually, it is estimated that about 4 billion units of consumer electronics for mobile communications are produced worldwide. This could lead to various ecological imbalances unless the design and disposal of the products are handled optimally. To illustrate how industry looks at and
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Annually, it is estimated that about 4 billion units of consumer electronics for mobile communications are produced worldwide. This could lead to various ecological imbalances unless the design and disposal of the products are handled optimally. To illustrate how industry looks at and responds to the increasing social awareness, this article describes how sustainability is successfully implemented in practice at a large Chinese company, developing and producing various kinds of electronic products used for communication. It also describes how a variety of eco-innovations and business models contribute to reducing the environmental impact; for example, through increased recovery and recycling. A new kind of eco-design procedure is presented along with a new methodology which shows how a mobile phone gradually becomes more sustainable from one generation to the next. The issues with and set-up of new eco-labeling schemes for mobile phones, eco-rating, is described in detail. The conclusion is that due to high competition between companies, the industry acts resourcefully and a lot is done to the save the ecological environment. Full article
(This article belongs to the Special Issue Electronic Waste — Impact, Policy and Green Design)
Open AccessArticle Impact of DEM Resolution on Puddle Characterization: Comparison of Different Surfaces and Methods
Water 2015, 7(5), 2293-2313; doi:10.3390/w7052293
Received: 24 March 2015 / Accepted: 11 May 2015 / Published: 18 May 2015
Cited by 3 | Viewed by 1189 | PDF Full-text (3977 KB) | HTML Full-text | XML Full-text
Abstract
DEM-based topographic characterization and quantification of surface depression storage are critical to hydrologic and environmental modeling. Mixed conclusions have been obtained from previous studies on the relationship between maximum depression storage (MDS) and DEM grid spacing, which is affected by different factors, such
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DEM-based topographic characterization and quantification of surface depression storage are critical to hydrologic and environmental modeling. Mixed conclusions have been obtained from previous studies on the relationship between maximum depression storage (MDS) and DEM grid spacing, which is affected by different factors, such as topographic characteristics, surface delineation methods and DEM interpolation/aggregation methods. The objective of this study was to evaluate the effects of DEM resolution on topographic characterization with the consideration of these three factors. Twenty-three topographic surfaces (including ideal surfaces, laboratory-scale soil surfaces and watershed-scale land surfaces) were selected, and five software packages, ArcHydro, PCRaster, HEC-GeoHMS, TauDEM and PD (puddle delineation), were used for surface delineation. Our results indicated that MDS, maximum ponding area (MPA) and the number of puddles (NP) decreased with increasing grid spacing for most smoother surfaces due to the loss of topographic detail. For most rough surfaces (e.g., mountain-type surfaces with significant variations in surface elevations), however, the changing patterns of MDS and MPA varied with an increase in grid spacing mainly due to the unreal “artificial depressions/puddles” generated during the interpolation/aggregation process. This study emphasizes the importance of topographic characteristics, DEM resolution and surface delineation methods. Full article

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