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Nontargeted identification of peptides and disinfection byproducts in water

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Journal of Environmental Sciences 2016年第4期28卷 259-266页

作者： Yanan Tang Ying Xu Feng li lindsay Jmaiff steve E.Hrudey Xing-Fang li Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyUniversity of Alberta Department of Computer Science University of Alberta

A broad range of organic compounds are known to exist in drinking water sources and serve as precursors of disinfection byproducts（DBPs）.Epidemiological findings of an association of increased risk of bladder cancer with the consumption of chlorinated water has resulted in health concerns about *** are thought to be an important category of DBP precursors in ***,little is known about the actual presence of peptides and their DBPs in drinking water because of their high sample complexity and low *** address this challenge and identify peptides and non-chlorinated/chlorinated peptide DBPs from large sets of organic compounds in water,we developed a novel high throughput analysis strategy,which integrated multiple solid phase extraction（SPE）,high performance liquid chromatography（HPlC）separation,and non-target identification using precursor ion exclusion（PIE）high resolution mass spectrometry（MS）.After MS analysis,structures of candidate compounds,particularly peptides,were obtained by searching against the Human Metabolome Database（HMDB）.Using this strategy,we successfully detected 625 peptides（out of 17,205 putative compounds）and 617 peptides（out of 13,297）respectively in source and finished water *** source and finished water samples had 501 peptides and amino acids in *** remaining 116 peptides and amino acids were unique to the finished *** a subset of 30 putative compounds for which standards were available,25 were confirmed using HPlC-MS *** analyzing the peptides identified in source and finished water,we successfully confirmed three disinfection reaction pathways that convert peptides into toxic DBPs.

关键词： Nontargeted detection Water analysis Mass spectrometry Peptide Disinfection byproducts

Fitting Full X-Ray Diffraction Patterns for Quantitative Analysis: A Method for Readily Quantifying Crystalline and Disordered Phases

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Advances in Materials Physics and Chemistry 2013年第1期3卷 47-53页

作者： steve J. Chipera David l. Bish Chesapeake Energy Corporation Oklahoma City Oklahoma USA Indiana University Bloomington Indiana USA

Fitting of full X-ray diffraction patterns is an effective method for quantifying abundances during X-ray diffraction (XRD) analyses. The method is based on the principal that the observed diffraction pattern is the sum of the individual phases that compose the sample. By adding an internal standard (usually corundum) to both the observed patterns and to those for individual pure phases (standards), all patterns can all be normalized to an equivalent intensity based on the internal standard intensity. Using least-squares refinement, the individual phase proportions are varied until an optimal match is reached. As the fitting of full patterns uses the entire pattern, including background, disordered and amorphous phases are explicitly considered as individual phases, with their individual intensity profiles or “amorphous humps” included in the refinement. The method can be applied not only to samples that contain well-ordered materials, but it is particularly well suited for samples containing amorphous and/or disordered materials. In cases with extremely disordered materials where no crystal structure is available for Rietveld refinement or there is no unique intensity area that can be measured for a traditional RIR analysis, full-pattern fitting may be the best or only way to readily obtain quantitative results. This approach is also applicable in cases where there are several coexisting highly disordered phases. As all phases are considered as discrete individual components, abundances are not constrained to sum to 100%.

关键词： Full-Pattern Quantitative X-Ray Diffraction XRD

Computer solutions in physics with applications in astrophysics, biophysics, differential equations, and engineering steve Van Wyk.

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A strategy for rock/coal outburst prevention

2008年

作者： steve Van Wyk.

ISBN: (纸本)9789812709363

With the great progress in numerical methods and the speed of the modern personal computer, if you can formulate the correct physics equations, then you only need to program a few lines of code to get the answer. Where other books on computational physics dwell on the theory of problems, this book takes a detailed look at how to set up the equations and actually solve them on a PC. Focusing on popular software packages like Mathematica, Maple and Matlab, the book offers undergraduate student a comprehensive treatment of the methodology used in programing solutions to equations in physics. Contents: Equations of Motion; Vibrations and Waves; Building Differential Equation; Partial Differential Equations; Applications.

关键词： Physics

来源：畅想之星图书光盘版（南... 评论

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Journal of Coal Science & Engineering(China) 2007年第3期13卷 225-229页

作者： D.H. steve Zou 程久龙 Mineral Resource Engineering Dalhousie University Halifax B3J1Z1 Key laboratory of Mine Disaster Prevention and Control Shandong University of Science ＆ Technology Qingdao 266510 China

The current practice of rock/coal outburst monitoring, prevention and control was reviewed. The uncertainty of major factors contributing to the occurrence of such hazards and the complexicity of mining conditions surrounding the occurrence were analyzed. A strategic concept for rock/coal outburst prevention was introduced. The objective is to identify the bursting potential in an area, rather than predicting the bursting, by introducing a multi- dimension index model： potential-of-bursting （POB）, taking into consideration major contributing factors. In application, once the index has passed certain critical level indicating high risk, actions must be taken to reduce the bursting potential and to effectively prevent the hazard from occurring. A conceptual 2D model involving stress and methane pressure was described to demonstrate the methodology for determining the POB. However in practice, a POB model has to be established through experiments, field monitoring and calibration against case studies. To achieve this objective, coordinated research and international collaboration will be needed.

关键词： rock/coal outbursts mine hazards bursting potential

N-Nitrosamine formation from chloramination of two common ionic liquids

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Journal of Environmental Sciences 2020年第1期32卷 341-348页

作者： Ian J.Vander Meulen Ping Jiang Di Wu steve E.Hrudey Xing-Fang li Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of Alberta

Ionic liquids(Ils)are a class of solvents increasingly used as"green chemicals."Widespread applications of Ils have led to concerns about their accidental entry to the *** have been assessed for some environmental impacts;however,little has been done to characterize their potential impacts on drinking water if Ils accidentally enter surface *** cations are often aromatic or alkyl quaternary amines that resemble structures of previously confirmed N-nitrosamine(NA)***,this study has evaluated two common Ils,1-ethyl-3-methylimidazolium bromide(EMIm Br)and 1-ethyl-1-methylpyrrolidinium bromide(EMPyr Br),for their NA formation *** Il species was reacted with pre-formed monochloramine under various laboratory *** reaction mixtures were extracted using liquid–liquid extraction and analyzed for NAs using high performance liquid chromatography tandem mass *** low concentration of Il(250μmol/l),the yields of NAs(NMEA or NPyr)increased with increasing doses of monochloramine from both Il *** total NA yield was as high as 2.5±0.3 ng/mg from EMIm Br,and as high as 8.6±0.8 ng/mg from EMPyr *** high concentration of Il(5 mmol/l),the NA yield reached a maximum at 2.5 mmol/l NH2Cl,and then decreased with subsequent increases in the reactant concentrations,demonstrating Ils’solvent *** study re-emphasizes the importance of preventing discharge of Ils to water bodies to prevent secondary impacts on drinking water.

关键词： Ionic liquids N-nitrosamine liquid–liquid extraction HPlC–MS/MS DBPs

Sensitivity analysis on parameter changes in underground mine ventilation systems

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 251-255页

作者： lI Gary KOCSIS Charles HARDCASTlE steve Mining and Mineral Sciences laboratories Natural Resources Canada Sudbury P3E 5P5 Canada

A more efficient mine ventilation system, the ventilation-on-demand （VOD） system, has been proposed and tested in Canadian mines recently. In order to supply the required air volumes to the production areas of a mine, operators need to know the cause and effect of any changes requested from the VOD system. The sensitivity analysis is developed through generating a cause and effect matrix of sensitivity factors on given parameter changes in a ventilation system. This new utility, which was incorporated in the 3D-CANVENT mine ventilation simulator, is able to predict the airflow distributions in a ventilation network when underground conditions and ventilation controls are changed. For a primary ventilation system, the software can determine the optimal operating speed of the main fans to satisfy the airflow requirements in underground workings without necessarily using booster fans and regulators locally. An optimized fan operating speed time-table would assure variable demand-based fresh air delivery to the production areas effectively, while generating significant savings in energy consumption and operating cost.

关键词： sensitivity factors ventilation system airflow branch resistance fixed quantity fan speed

Perinatal stem cells: A promising cell resource for tissue engineering of craniofacial bone

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World Journal of Stem Cells 2015年第1期7卷 149-159页

作者： Jia-Wen Si Xu-Dong Wang steve GF Shen Department of Oral and Craniomaxillofacial Science Shanghai Ninth People’s Hospital College of Stomatology Shanghai Jiao Tong University School of Medicine

In facing the mounting clinical challenge and suboptimal techniques of craniofacial bone defects resulting from various conditions, such as congenital malformations, osteomyelitis, trauma and tumor resection, the ongoing research of regenerative medicine using stem cells and concurrent advancement in biotechnology have shifted the focus from surgical reconstruction to a novel stem cell-based tissue engineering strategy for customized and functional craniofacial bone regeneration. Given the unique ontogenetical and cell biological properties of perinatal stem cells, emerging evidence has suggested these extraembryonic tissue-derived stem cells to be a promising cell source for extensive use in regenerative medicine and tissue engineering. In this review, we summarize the current achievements and obstacles in stem cell-based craniofacial bone regeneration and subsequently we address the characteristics of various types of perinatal stem cells and their novel application in tissue engineering of craniofacial bone. We propose the promising feasibility and scope of perinatal stem cell-based craniofacial bone tissue engineering for future clinical application.

关键词： Craniofacial bone regeneration Bone tissueengineering Extraembryonic tissue Perinatal stem cells

A novel strategy for processing,production and quality control of an iron-free nutraceutical supplement that rapidly restores iron-dependent hemoglobin in red blood cells

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Food Production, Processing and Nutrition 2020年第1期2卷 258-260页

作者： Debasis Bagchi Bernard W.Downs Manashi Bagchi steve Kushner VNI Inc. LederachPAUSA Texas Southern University College of Pharmacy and Health SciencesHoustonTXUSA Dr.Herbs llC ConcordCAUSA AlM R&D OldsmarFLUSA

We hypothesize that Iron-Deficiency Anemia(IDA)has been *** the body,low blood iron is not caused by a *** primary cause of low iron,appearing to be IDA,is the expenditure of alkalinizing histidine,from heme protein,which requires the cleavage of iron and its repartitioning to other storage *** an alkaline buffer,histidine is released to counterbalance the increase in an anaerobic hypoxic(*** acidic)blood pH,thereby maintaining a pH of *** research team coined the more accurate term for this pathogenic condition,“Chronic Anemia Syndrome”(CAS).

关键词： Anemia A multi-nutrient nutraceutical VMP35 Hematology Hemoglobin