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Tyrosine metabolic enzymes from insects and mammals：A comparative perspective

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Insect Science 2014年第1期21卷 13-19页

作者： christopher john Vavricka Qian Han Prajwalini Mehere Haizhen Ding Bruce M. christensen and Jianyong Li Research Network of Immunity and Health (RNIH) Beijing Institutes of Life Science Chinese Academy of Sciences BeUing China Department of Biochemistry Virginia Polytechnic and State University Blacksburg VA 24061 USA Department of Tuberculosis The Foundation for Medical Research Mumbai India and Department of Pathobiology University of Wisconsin-Madison Madison Wl 53706 USA

Differences in the metabolism of tyrosine between insects and mammals present an interesting example of molecular evolution. Both insects and mammals possess finetuned systems of enzymes to meet their specific demands for tyrosine metabolites; however, more homologous enzymes involved in tyrosine metabolism have emerged in many insect species. Without knowledge of modem genomics, one might suppose that mammals, which are generally more complex than insects and require tyrosine as a precur sor for important catecholamine neurotransmitters and for melanin, should possess more enzymes to control tyrosine metabolism. Therefore, the question of why insects actually possess more tyrosine metabolic enzymes is quite interesting. It has long been known that insects rely heavily on tyrosine metabolism for cuticle hardening and for innate immune responses, and these evolutionary constraints are likely the key answers to this question. In terms of melanogenesis, mammals also possess a high level of regulation; yet mam malian systems possess more mechanisms for detoxification whereas insects accelerate pathways like melanogenesis and therefore must bear increased oxidative pressure. Our research group has had the opportunity to characterize the structure and function of many key proteins involved in tyrosine metabolism from both insects and mammals. In this mini review we will give a brief overview of our research on tyrosine metabolic enzymes in the scope of an evolutionary perspective of mammals in comparison to insects.

关键词： arylalkylamine N-acetyltransferase (aaNAT) Enzymology L-DOPAdecarboxylase (DDc) melanogenesis tyrosine metabolism

Influence of coagulation mechanisms and floc formation on filterability

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Journal of Environmental Sciences 2017年第7期29卷 338-345页

作者： Ruyuan Jiao Rolando Fabris christopher W.K.chow Mary Drikas john van Leeuwen Dongsheng Wang Zhizhen Xu State Key Laboratory of Environmental Aquatic chemistry Research Center for Eco-Environmental SciencesChinese Academy of Sciences Australian Water Quality centre South Australian Water Corporation centre for Water Management and Reuse School of Natural and Built EnvironmentsUniversity of South Australia Key Laboratory of Occupational Safety and Health Beijing Municipal Institute of Labor Protection

Minimizing particles in water is a key goal for improving drinking water quality and *** media filtration process,as the last step of the solid–liquid separation process,is largely influenced by the characteristics of flocs,which are formed and controlled within the coagulation *** a laboratory-based study,the impacts of the physical characteristics of flocs formed using aluminum sulfate on the filtration treatment of two comparative water samples were investigated using a photometric dispersion analyzer and a filterability *** general,the optimum dosage for maximizing filterability was higher than that for minimizing turbidity under neutral p H *** a monomeric aluminum-based coagulant,the charge neutralization mechanism produced better floc characteristics,including floc growth speed and size,than the sweep flocculation *** addition,the charge neutralization mechanism showed better performance compared to sweep flocculation in terms of DOc removal and floc filterability improvement for both waters,and showed superiority in turbidity removal only when the raw water had high *** the different mechanisms,the ways that floc characteristics impacted on floc filterability also *** low variation in floc size distribution obtained under the charge neutralization mechanism resulted in the flocs being amenable to removal by filtration *** the sweep flocculation mechanism,increasing the floc size improved the settling ability of flocs,resulting in higher filter efficiency.

关键词： coagulation mechanisms Floc characteristics Filterability Turbidity

chloramine demand estimation using surrogate chemical and microbiological parameters

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Journal of Environmental Sciences 2017年第7期29卷 1-7页

作者： Sina Moradi Sanly Liu christopher W.K.chow john van Leeuwen David cook Mary Drikas Rose Amal School of chemical Engineering The University of New South Wales Australian Water Quality centre SA Water Corporation centre for Water Management and Reuse School of Natural and Built EnvironmentsUniversity of South Australia

A model is developed to enable estimation of chloramine demand in full scale drinking water supplies based on chemical and microbiological factors that affect chloramine decay rate via nonlinear regression analysis *** model is based on organic character（specific ultraviolet absorbance（SUVA）） of the water samples and a laboratory measure of the microbiological（Fm） decay of *** applicability of the model for estimation of chloramine residual（and hence chloramine demand） was tested on several waters from different water treatment plants in Australia through statistical test analysis between the experimental and predicted *** showed that the model was able to simulate and estimate chloramine demand at various times in real drinking water *** elucidate the loss of chloramine over the wide variation of water quality used in this study,the model incorporates both the fast and slow chloramine decay *** significance of estimated fast and slow decay rate constants as the kinetic parameters of the model for three water sources in Australia was *** was found that with the same water source,the kinetic parameters remain the *** modelling approach has the potential to be used by water treatment operators as a decision support tool in order to manage chloramine disinfection.

关键词： chloramine demand Drinking water treatment plants Modelling

Developing a chloramine decay index to understand nitrification:A case study of two chloraminated drinking water distribution systems

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Journal of Environmental Sciences 2017年第7期29卷 170-179页

The management of chloramine decay and the prevention of nitrification are some of the critical issues faced by water utilities that use chloramine as a *** this study,potential association between high performance size exclusion chromatography（HPSEc）data obtained with multiple wavelength Ultraviolet（UV） detection from two drinking water distribution systems in Australia and nitrification occurrence was *** increase in the absorbance signal of HPSEc profiles with UV detection at λ = 230 nm between apparent molecular weights of 200 to 1000 Da was observed at sampling sites that experienced rapid chloramine decay and nitrification while its absorbance signal at λ =254 nm decreased.A chloramine decay index（c.D.I） defined as the ratio of area beneath the HPSEc spectra at two different wavelengths of 230 and 254 nm,was used in assessing chloramine decay *** *** of waters at locations that experienced nitrification were consistently higher than locations not experiencing nitrification.A simulated laboratory study showed that the formation of nitrite/nitrate and/or soluble microbial products and/or the release of extracellular polymeric substances（EPS） during nitrification may contribute to the *** findings suggest that c.D.I derived from HPSEc with multiple wavelength UV detection could be an informative index to track the occurrence of rapid chloramine decay and nitrification.

关键词： HPSEc Water distribution systems Nitrification chloramine decay

Liver transplantation in patients with incidental hepatocellular carcinoma/cholangiocarcinoma and intrahepatic cholangiocarcinoma： a single-center experience

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Hepatobiliary & Pancreatic Diseases International 2017年第3期16卷 264-270页

作者： Mohammed Elshamy Naftali Presser Abdulrahman Y Hammad Daniel J Firl christopher coppa john Fung Federico N Aucejo Hepatobiliary and Transplant Surgery Digestive Disease and Surgery Institute Cleveland Clinic Cleveland OH USA Imaging Institute Cleveland Clinic Cleveland OH USA

BAcKGROUND： Reports of fiver transplantation （LT） in patients with mixed hepatocellular carcinoma/cholangiocarcinoma （Hcc/cc） and intrahepatic cholangiocarcinoma （Icc） are modest and have been mostly retrospective after pathological categorization in the setting of presumed Hcc. Some studies suggest that patients undergoing LT with small and unifocal Icc or mixed Hcc/cc can achieve about 40%-60% 5-year post-transplant survival. The study aimed to report our experience in patients undergoing LT with explant pathology revealing Hcc/cc and Icc. METHODS： From a prospectively maintained database, we performed cohort analysis. We identified 13 patients who underwent LT with explant pathology revealing Hcc/cc or Icc. RESULTS： The observed recurrence rate post-LT was 31% （4/13） and overall survival was 85%, 51%, and 51% at 1, 3 and 5 years, respectively. Disease-free survival was 68%, 51%, and 41% at 1, 3 and 5 years, respectively. In our cohort, four patients would have qualified for exception points based on updated Hcc Organ Procurement and Transplantation Network imaging guidelines. cONcLUSIONS： Lesions which lack complete imaging characteristics of Hcc may warrant pre-LT biopsy to fully elucidate their pathology. Identified patients with early Hcc/cc or Icc may benefit from LT if unresectable. Additionally, incorporating adjunctive perioperative therapies such as in the case of patients undergoing LT with hilar cholangiocarcinoma may improve outcomes but this warrants further investigation.

关键词： mixed hepatocellular carcinoma/ cholangiocarcinoma liver transplantation survival outcomes

Pathological changes to the Subcortical Visual System and its Relationship to Visual Hallucinations in Dementia with Lewy Bodies

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Neuroscience Bulletin 2019年第2期35卷 295-300页

作者： Daniel Erskine john-Paul Taylor Alan Thomas Daniel collerton Ian McKeith Ahmad Khundakar Johannes Attems christopher Morris Institute of Neuroscience Newcastle University Northumberland Tyne and Wear NHS Trust School of Science Engineering and Design Teesside University

Introduction Recurrent complex visual hallucinations are a core clinical feature of dementia with Lewy bodies(DLB)and are typically well-formed,often consisting of figures,such as people or animals(1)Despite the profound impact upon patients and caregivers in DLB,the aetiopathology of visual hallucinations remains largely *** this article we discuss the anatomy of the human visual system,hypotheses of the genesis of visual hallucinations in DLB,and imaging and neuropathological studies that have attempted to understand visual hallucinations on a functional and anatomical basis.

关键词： Pathological Visual System Lewy Bodies

Tetracycline-inducible protein expression in pancreatic cancer cells: Effects of capG overexpression

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World Journal of Gastroenterology 2011年第15期17卷 1947-1960页

作者： Sarah Tonack Sabina Patel Mehdi Jalali Taoufik Nedjadi Rosalind E Jenkins christopher Goldring john Neoptolemos Eithne costello Liverpool cR-UK centre Department of Molecular and Therapeutic Cancer MedicineUniversity of Liverpool Liverpool L69 3GA United Kingdom MRc centre forDrug Safety Science Department of Pharmacology and Therapeutics School of Biomedical Sciences University of Liverpool L69 3GA United Kingdom National Institute for Health Research Pancreatic Biomedical Research Unit Liverpool L69 3GA United Kingdom

AIM: To establish stable tetracycline-inducible pancreatic cancer cell lines. METHODS: Suit-2, MiaPaca-2, and Panc-1 cells were transfected with a second generation reverse tetracycline-controlled transactivator protein (rtTA2S-M2), under the control of either a cytomegalovirus (cMV) or a chicken β-actin promoter, and the resulting clones were ***: Use of the chicken (β-actin) promoter proved superior for both the production and maintenance of doxycycline-inducible cell lines. The system proved versatile, enabling transient inducible expression of a variety of genes, including GST-P, cYP2E1, S100A6, and the actin capping protein, capG. To determine the physiological utility of this system in pancreatic cancer cells, stable inducible capG expressors were established. Overexpressed capG was localised to the cytoplasm and the nuclear membrane, but was not observed in the nucleus. High capG levels were associated with enhanced motility, but not with changes to the cell cycle, or cellular proliferation. In capG-overexpressing cells, the levels and phosphorylation status of other actin-moduating proteins (cofilin and Ezrin/Radixin) were not altered. However, preliminary analyses suggest that the levels of other cellular proteins, such as ornithine aminotransferase and enolase, are altered upon capG induction. cONcLUSION: We have generated pancreatic-cancer derived cell lines in which gene expression is fully controllable.

关键词：诱导表达蛋白表达癌细胞四环素胰腺癌过表达肌动蛋白 cYP2E1

Research advances on internal processes affecting tropical cyclone intensity change from 2018–2022

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Tropical cyclone Research and Review 2023年第1期12卷 10-29页

作者： Xiaomin chen christopher M.Rozoff Robert F.Rogers Kristen L.corbosiero Dandan Tao Jian-Feng Gu Falko Judt Eric A.Hendricks Yuqing Wang Michael M.Bell Daniel P.Stern Kate D.Musgrave john A.Knaff john Kaplan NOAA/OAR/Atlantic Oceanographic and Meteorological Laboratory MiamiUSA University of Alabama in Huntsville HuntsvilleUSA National center for Atmospheric Research BoulderUSA University at Albany/State University of New York AlbanyUSA University of Bergen BergenNorway Nanjing University NanjingChina University of Reading ReadingUK University of Hawaii at Manoa HonoluluUSA colorado State University Fort CollinsUSA University corporation for Atmospheric Research MontereyUSA NOAA center for Satellite Applications and Research Fort CollinsUSA Department of Atmospheric and Earth Science University of Alabama in HuntsvilleHuntsvilleUSA

This contribution summarizes the significant progress in a variety of topic areas related to internal tropical cyclone(Tc)intensity change processes over 2018–2022 from the WMO Tenth International Workshop on Tropical cyclones(IWTc-10).These topic areas include surface and boundary layer processes;Tc internal structure and microphysical processes;and,radiation interactions with *** studies better frame the uncertainty in the surface drag and enthalpy coefficients at high wind *** parameters greatly impact Tc intensity and it is therefore important that more direct measurements of these boundary layer parameters are *** significant scientific strides have been made in Tc boundary *** advancements have been achieved through improved coupled models,large-eddy simulations,theoretical advance-ments,and detailed *** is now clear that the research field needs to better represent the eddy viscosity throughout the depth of the boundary ***,detailed study of coherent structures in Tc boundary layers will likely be a propitious direction for the research ***,in-depth observational field campaigns and assiduous data analysis have made significant headway into verifying theory and modeling studies of intensification processes related to Tc vortex alignment,efficient latent heating distributions,and overall 3D *** efforts have also been made to better understand the intricate roles radiative processes play in Tc evolution and intensity ***,some promising progress has been made in the development of time-dependent theories of Tc intensification and the predictability of internal Tc intensity ***,there have been well-earned gains in the understanding of intensity change processes intrinsic to the Tc system,but the journey is not *** paper highlights some of the most relevant and important research areas that are still shedding new light into internal fa

关键词： Tropical cyclone Intensity Internal dynamics Boundary-layer processes Observations Predictability

改进的平均应力准则对钛合金断裂强度的评估(英文)

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Transactions of Nonferrous Metals Society of china 2013年第4期23卷 1072-1079页

作者： H.BRIGHTON ISAAc john T.christopher Sardar Raja college of Engineering AlangulamTirunelveli-627808India Government college of Engineering PerumalpuramTirunelveli-627007India

结构完整性方法通常用来论证工程零件载荷传递的合理性。损伤模型对含尖缺口的钛合金断裂强度的预测取决于材料的无缺口强度以及缺口损伤区前的临界长度。损伤区的临界长度通常取决于材料、试样以及尖缺口的尺寸。平均应力准则作为一种... 详细信息

结构完整性方法通常用来论证工程零件载荷传递的合理性。损伤模型对含尖缺口的钛合金断裂强度的预测取决于材料的无缺口强度以及缺口损伤区前的临界长度。损伤区的临界长度通常取决于材料、试样以及尖缺口的尺寸。平均应力准则作为一种应力断裂准则,常用来对含尖缺口的钛合金抗拉强度进行精确预测。基于不同厚度的中心裂缝钛合金的断裂数据,对平均应力准则进行改进。缺口(断裂)强度的预估值与测试结果接近,表明改进的平均应力准则可以简便地预测缺口的抗拉强度。

关键词：钛合金中心裂纹拉伸试样应力准则失效评估图断裂强度