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Combining innovative science and policy to improve air quality in cities with refining and chemicals manufacturing： the case study of Houston, texas, USA

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 293-304页

作者： david t. Allen University of texas Austin Department of Chemical Engineering and Center for Energy and Environmental Resources Austin TX 78759 USA

In Houston, a combination of urban emissions from a city of 4 million people, coupled with emissions from extensive petroleum refining and chemical manufacturing, leads to conditions for photochemistry that are unique in the United States, and historically, the city had experienced some of the highest ozone concentrations recorded in the United States. Large air quality field studies （the texas Air Quality Studies or texAQS I and II） were conducted to determine root causes of the high ozone concentrations. Hundreds of air quality investigators, from around the world, deployed instruments on aircraft, on ships, and at fixed ground sites to make extensive air quality measurements; detailed photochemical modeling was used to interpret and assess the implications of the measurements. the texas Air Quality Studies revealed that both continuous and episodic emissions of light alkenes, which came to be called highly reactive volatile organic compounds, played a critical role in the formation of ozone and other photochemical oxidants in the region. Under- standing and quantifying the role of these emissions in regional air quality required innovations in characterizing emissions and in photochemical modeling. Reducing emissions required innovative policy approaches. these coupled scientific and policy innovations are described, and the result, substantially cleaner air for Houston, is documented. the lessons learned from the Houston air quality experience are relevant to cities with similar population and industrial profiles around the world.

关键词： ozone air quality highly reactive volatile organic compounds Houston

Regulation of proprietary traditional Chinese medicines in Australia

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Chinese Journal of Natural Medicines 2017年第1期15卷 12-14页

作者： david t. Graham ISO technical committee 249 (1SO/tC 249) 7-C Shuguang Building 189 Pu 'an Road Shanghai 200021 China

this review article describes the regulation of proprietary Chinese medicines for the Australian market, which may permit many medicines used in traditional Chinese Medicine to have a simplified process of market acce... 详细信息

关键词： Regulation Australia Chinese medicines

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Influence of incubation temperature on sea turtle hatchling quality

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Integrative Zoology 2017年第5期12卷 352-360页

作者： david t.BOOtH School of Biological Sciences The University of QueenslandSt LuciaQueenslandAustralia

Since the 1980s it has been known that incubation temperature influences the sex ratio of sea turtle hatchlings emerging from their nests,and there has been much speculation on how global climate change might threaten sea turtle populations by raising nest temperatures and causing highly female-biased hatchling sex *** recently,studies have indicated that incubation temperature can also influence the size and locomotor performance of sea turtle *** I review recent studies that have explored the influence of incubation temperature on sea turtle hatchling quality in terms of hatchling morphology and locomotor performance.I also discuss the likely underlying mechanisms responsible for incubation temperature-induced differences in hatchling locomotor performance,and how an increase in nest temperature associated with global warming might affect recruitment of sea turtle hatchlings.

关键词： locomotor performance nest temperature phenotype sea turtle hatchling

Colorectal cancer and dysplasia in inflammatory bowel disease

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World Journal of Gastroenterology 2008年第17期14卷 2662-2669页

作者： timothy L Zisman david t Rubin Clinical Research Fellow in Gastro-enterology the University of Chicago Medical Center the University of Chicago Medical Center

Both ulcerative colitis and Crohn’s disease carry an increased risk of developing colorectal cancer. Established risk factors for cancer among patients with inflammatory bowel disease (IBD) include the younger age at diagnosis, greater extent and duration of disease, increased severity of inflammation, family history of colorectal cancer and coexisting primary sclerosing cholangitis. Recent evidence suggests that current medical therapies and surgical techniques for inflammatory bowel disease may be reducing the incidence of this complication. Nonetheless heightened vigilance and a careful, comprehensive approach to prevent or minimize the complications of invasive cancer are warranted in this unique cohort of patients. Current guidelines for the prevention and early detection of cancer in this high risk population are grounded in the concept of an inflammation-dysplasia- carcinoma sequence. A thorough understanding of the definition and natural history of dysplasia in IBD, as well as the challenges associated with detection and interpretation of dysplasia are fundamental to developing an effective strategy for surveillance and prevention, and understanding the limitations of the current approach to prevention. this article reviews the current consensus guidelines for screening and surveillance of cancer in IBD, as well as presenting the evidence and rationale for chemoprevention of cancer and a discussion of emerging technologies for the detection of dysplasia.

关键词： Cancer Dysplasia Inflammatory Bowel Disease Ulcerative Colitis Crohn's Disease Chemoprevention

Risk of post-operative complications associated with anti-tNF therapy in inflammatory bowel disease

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World Journal of Gastroenterology 2012年第3期18卷 197-204页

作者： tauseef Ali Laura Yun david t Rubin University of Oklahoma Health Sciences Center & VA Medical Center. Section of Digestive Diseases and Nutrition University of Chicago Inflammatory Bowel Disease Center

there have been increasing concerns regarding the safety of perioperative anti-tumour necrosis factor (anti-tNF) α agents. We performed a literature review to evaluate the post-operative complications associated with perioperative anti-tNF use in patients with inflammatory bowel disease. A comprehensive review was performed with a literature search utilizing Pub Med, Cochrane, OVID and EMBASE databases according to published guidelines. to date, there are only data for infliximab. there are three published studies which have assessed post-operative complications with perioperative infliximab use in patients with Crohn' s disease (CD), four studies in ulcerative colitis (UC) patients, and one study on both CD and UC patients. two out of the three studies in CD patients showed no increased post-operative complications associated with perioperative infliximab. two out of four studies in UC patients also did not show an increase in post-operative complications, and the combined study with CD and UC patients did not show an increased risk as well. Studyresults could not be combined secondary to significant differences in study designs, patient population and definition of their endpoints. there appears to be a risk of post-operative complications associated with tNF therapy in some patients. Based on these data, careful patient selection and prospective data collection should be performed.

关键词： Crohn's disease Ulcerative colitis Colectomy Post-operative complications

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Biobanking and omics

Frontiers in Biology 2018年第4期13卷 287-292页

作者： david t. Harris Executive Director Biorepository University of Arizona PO Box 245221. AHSC 6122 Tucson AZ 85724 USA

BACKGROUND： the ＂Era of Big Data＂ and ＂Precision Medicine＂ is now upon us. that is, interrogation of large data sets obtained from groups of similar patients or from the patient themselves over time will now hypothetically permit therapies to be designed to provide maximal efficacy with minimal side effects. However, such discoveries depend upon recruitment of very large numbers of subjects （tens of thousands） along with their associated biospecimens and medical records. When considering the establishment of a biobank or the refocusing of an existing repository for the purpose of＂omics＂ research （i.e., genomics, metabolomics, proteomics, microbiomics, etc.） and/or precision medicine, there are a number of considerations to ponder. Each of these facets is discussed. OBJECtIVE： the objective of this review is to describe best practices for the establishment and operations ofa biobank that will be used for omics （genomics, proteomics, metabolomics, microbiomics） analyses based on published literature and our own practical experiences. MEtHODS： We describe the most commonly described approaches to a variety of biobanking issues, including our own practical experiences over the past 5 years. RESULtS： Based on the particular biobanking situation and downstream application, we have described best practices based on the literature and own experience, taking into consideration ease of application and costs. CONCLUSIONS： the banking of various types of clinical biospecimens has many valuable uses but often depends on overall costs versus sample utility. In addition, specimen flexibility is important but is influenced by the ease or difficulty of the application. It is always preferable to collect and stored a biospecimen in a format that allows for multiple types of downstream analyses, but that often requires additional expertise, equipment and reagents that can increase overall costs. We have described the methodologies most successfully applied to many situations.

关键词： biobanking genomics metabolomics microbiomics methodology precision medicine big data

Super-hydrophobic stearic acid layer formed on anodized high purified magnesium for improving corrosion resistance of bioabsorbable implants

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Journal of Magnesium and Alloys 2018年第4期6卷 327-336页

作者： Sohrab Khalifeh t.david Burleigh Materials&Metallurgical Engineering Department New Mexico Institute of Mining&TechnologySocorroNM 87123USA

Magnesium and its alloys are ideal candidates for bioabsorbable ***,they can dissolve too rapidly in the human body for most *** this research,high purified magnesium(HP-Mg)was coated with stearic acid(SA)to slow the corrosion rate of magnesium in simulated body fluid at 37±1°***-Mg was anodized(AC and DC voltages)to form an oxide/hydroxide layer,and then it was immersed in a SA *** SA coated layer surface,anodized layer,and the thickness of the oxide/hydroxide layer were investigated with Scanning Electron Microscopy(SEM).Electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization(PDP)were used to estimate the corrosion rate of HP-Mg *** results confirm that the hydrophobic coating can decrease the corrosion rate of HP-Mg by more than *** protectiveness of coated layer for anodized specimens with AC voltage continue for 2 and 3 *** the HP-Mg coated anodized with DC voltage,the coated layer could improve the corrosion resistance for only a few days.

关键词： Magnesium Biomaterials Hydrophobic layer Stearic acid Simulated body fluid Electrochemical impedance spectroscopy

Quality measures of reconstruction filters for stereoscopic volume rendering

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Computational Visual Media 2016年第1期2卷 19-30页

作者： david A.t.Roberts Ioannis Ivrissimtzis School of Engineering and Computing Sciences Durham University

In direct volume rendering(DVR), the choice of reconstruction filter can have a significant effect on the visual appearance of the images produced and thus, on the perceived quality of a DVR rendered scene. this paper presents the results of a subjective experiment where participants stereoscopically viewed DVR rendered scenes and rated their subjective *** statistical analysis of the results focuses on the relationship between the quality of the stereoscopic scene and properties of the filters such as post-aliasing and smoothing, as well as the relationship between the quality of the stereoscopic scene and properties of the rendered images such as shape *** experiment evaluated five reconstruction filters on four different volumetric datasets. Participants rated the stereoscopic scenes on four quality measures:depth quality, depth layout, lack of jaggyness, and sharpness. the results show that the correlation between the quality measures and post-aliasing and smoothing, which are properties associated with each reconstruction filter, is moderate and statistically insignificant. On the other hand, the correlation between the quality measures and compactness, which is a property specific to each rendered image, is strong and statistically significant.

关键词： direct volume rendering(DVR) reconstruction filters stereoscopic user evaluations

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Modeling of cable vibration effects of cable-stayed bridges

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 74-85页

作者： S.H.Cheng david t.Lau Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanadaPost-doctoral fellow Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanada Professor

the analysis of dynamic responses of cable-stayed bridges subjected to wind and earthquake loads generally considers only the motions of the bridge deck and *** influence of the stay cable vibration on the responses of the bridge is either ignored or considered by approximate *** transverse vibration of the stay cables,which can be significant in some cases,are usually neglected in previous *** the present study,a new three-node cable element has been developed to model the transverse motions of the *** interactions between the cable behavior and the other parts of the bridge superstructure are considered by the concept of dynamic *** nonlinear effect of the cable caused by its self-weight is included in the *** examples are presented to demonstrate the accuracy and efficiency of the proposed model. the impact of cable vibration behavior on the dynamic characteristics of cable-stayed bridges is discussed.

关键词： cable-stayed bridges cable vibration dynamics finite elements long-span structures

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