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A machine learning approach for regional geochemical data:Platinum-group element geochemistry vs geodynamic settings of the North Atlantic Igneous Province

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Geoscience Frontiers 2021年第3期12卷 42-59页

作者： j.rdan j.Lindsay Hannah S.R.Hughes Christopher M.Yeomans j.ns C.Ø.Andersen Iain mcdonald Camborne School of Mines University of ExeterPenryn CampusPenrynCornwall TR109FEUnited Kingdom School of Earth and Ocean Sciences Main CollegeCardiff UniversityPark PlaceCardiff CF103ATUnited Kingdom

Whilst traditional approaches to geochemistry provide valuable insights into magmatic processes such as melting and element fractionation,by considering entire regional data sets on an obj.ctive basis using machine learning algorithms(MLAs),we can highlight new facets within the broader data structure and significantly enhance previous geochemical *** platinum-group element(PGE)budget of lavas in the North Atlantic Igneous Province(NAIP)has been shown to vary systematically according to age,geographic location and geodynamic *** the large multi-element geochemical data set available for the region,MLAs were employed to explore the magmatic controls on these shifting *** key advantage of using machine learning in analysis is its ability to cluster samples across multi-dimensional(i.e.,multi-element)*** NAIP data set is manipulated using Principal Component Analysis(PCA)and t-Distributed Stochastic Neighbour Embedding(t-SNE)techniques to increase separability in the data alongside clustering using the k-means *** new multi-element classification is compared to the original geographic classification to assess the performance of both *** workflow provides a means for creating an obj.ctive high-dimensional investigation on a geochemical data set and particularly enhances the identification of metallogenic anomalies across the *** techniques used highlight three distinct multi-element end-members which successfully capture the variability of the maj.rity of elements included as input *** end-members are seen to fluctuate in prominence throughout the NAIP,which we propose reflects the changing geodynamic environment and melting ***,the variability of Pt and Pd are not reflected in MLA-based clustering trends,suggesting that they vary independently through controls not readily demonstrated by the NAIP maj.r or trace element data structure(i.e.,other proxies for magmatic differe

关键词： Platinum-group elements Machine learning Plume Geochemistry Metallogenesis Mantle

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H<sub>2</sub>Gas Charging of Zero-Valent Iron and TCE Degradation

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j.urnal of Environmental Protection 2012年第3期3卷 272-279页

作者： Chen Zhao eric j. Reardon Department of Earth and Environmental Sciences University of Waterloo Waterloo Canada Department of Earth and Environmental Sciences University of Waterloo Waterloo Canada.

Granular zero-valent iron (ZVI) has been widely used to construct permeable reactive barriers (PRB) for the in situ remediation of groundwater contaminated with halogenated hydrocarbons. In the anaerobic condition of most groundwater flow systems, iron undergoes corrosion by water and results in hydrogen gas generation. Several studies have shown that some of the hydrogen gas generated at the iron/water interface can diffuse into the iron lattice. Hydrogen gas also can be an electron donor for dechlorination of chlorinated compounds. In this study, the possibility of hydrogen gas bound in the lattice of ZVI playing a role in dehalogenation and improving the degradation efficiency of ZVI was evaluated. Two different granular irons were tested: one obtained from Quebec Metal Powders Ltd (QMP) and the other from Connelly-GPM. Ltd. For each type of iron, two samples were mixed with water and sealed in testing cells. Since the rate of hydrogen entry varies directly with the square root of the hydrogen pressure, one sample was maintained for several weeks under near-vacuum conditions to minimize the amount of hydrogen entering the iron lattice. The other sample was maintained for the same period at a hydrogen pressure of over 400 kPa to maximize the amount of hydrogen entering the iron lattice. The degradation abilities of the reacted ironsand the original iron materials were tested by running several sets of batch tests. The results of this study show little to no improvement of inorganic TCE degradation reactions due to the presence of lattice-stored hydrogen in iron material. This is probably due to the high energiesrequired to release hydrogen trapped in the iron lattice. However, there are certain chemical compounds that can promote hydrogen release from the iron lattice, and there may be bacteria that can utilize lattice-bound hydrogen to carry out dechlorination reactions.

关键词： Granular Zero-Valent Iron Hydrogen TCE Remediation Groundwater

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Important Aspects of Controlling Sulfur Dioxide in Brewing

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中外酒业 2019年第5期 49-64页

作者： eric j. Samp Dana Sedin MillerCoors Golden CO U.S.A. New Belgium Brewing Company Fort Collins CO U.S.A.

This paper discusses the relative importance of sulfur dioxide (SO2) to brewers because there are implications to beer quality, consumer health, and legal requirements. Overviews are provided on what SO2 is, its sources in beer, what quality parameters are impacted by SO2,what health implications are known, and labeling requirements. An overview of methodologies for measuring SO2 is given to educate brewers on the advantages and disadvantages of different methods with the aim to enlighten brewers to adopt a method that can be incorporated into their quality assurance program. Finally, an overview of published papers is summarized, along with general trouble-shooting guidelines for brewers to further their knowledge on controlling this critical yeast metabolite in their beers.

关键词： Controlling Sulfur Dioxide Brewing SO2

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<i>In Vitro</i>Model Systems to Investigate Drug Resistance Mechanisms in Pancreatic Cancer Cells

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Advances in Biological Chemistry 2015年第7期5卷 286-292页

作者： eric Romney Vinay j. Nagaraj Arizona College of Osteopathic Medicine Midwestern University Glendale Arizona Department of Biochemistry Midwestern University Glendale Arizona

With a 5-year survival rate of less than 6%, the diagnosis of pancreatic cancer is devastating news for any patient. Gemcitabine, the most commonly used chemotherapy drug, only improves survival by approximately 1.5 months. A maj.r obstacle to the treatment of pancreatic cancer with gemcitabine is the development of drug resistance. To better understand the precise mechanisms by which patient tumor cells gain resistance to gemcitabine, a cell culture model system that more accurately reflects the development of drug resistance in vivo is required. In this study, cultured pancreatic adenocarcinoma BxPC-3 cells were subj.cted to two different treatment regimens. The first method—termed pulse method—involves periodically treating separate cultures of BxPC-3 cells with constant predetermined doses of gemcitabine. The second treatment regimen—termed incremental method—consists of treating BxPC-3 cells with increasing doses of gemcitabine from 10 to 100 nM. While all treated cells showed enhanced resistance to gemcitabine, low-dose pulse treatments were sufficient to produce highly drug-resistant cells as evidenced by higher IC50 measurements. Pulse treatments also resulted in slower growth rates and increased doubling time of the drug-resistant cells. Morphological changes indicate cellular abnormalities linked to likely epithelial-to-mesenchymal transition and drug resistance. Our preliminary results indicate that the pulse method may better simulate resistance observed in patients undergoing chemotherapy and may serve as a superior model to investigate drug-resistance. This model can also help with identification of appropriate markers that determine the presence of drug-resistant cells and help clinicians adj.st treatment strategies to improve outcomes for patients suffering from pancreatic cancer.

关键词： Pancreatic Cancer Gemcitabine Drug-Resistance Pulse Method Incremental Method

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Wideband, 50 dB Attenuation Range Liquid Crystal Based Variable Optical Attenuator

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光学学报 2003年第S1期23卷 -页

作者： j.j. Pan Henry He eric Zhang Lightwaves 2020 Inc. 1323 Great Mall Drive Milpitas CA 95035 USALightwaves 2020 Inc. 1323 Great Mall Drive Milpitas CA 95035 USALightwaves 2020 Inc. 1323 Great Mall Drive Milpitas CA 95035 USA

A compact variable optical attenuator, covering C and L bands with over 50 dB attenuation range, is realized using a single liquid crystal cell with a tilted fused silica coating compensating the cell's small residual... 详细信息

关键词： VOA dB Attenuation Range Liquid Crystal Based Variable Optical Attenuator be Wideband into with very of Figure LC that high

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Effect of Cooling Rate on the Room Temperature Microstructure Following the Intercritical Deformation of Steel S460

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j.urnal of Iron and Steel Research International 2011年第S1期18卷 500-505页

作者： Hinton j.hn S Palmiere eric j.Rainforth W.Mark IMMPETUS Dept.Of Materials Science and EngineeringThe University of SheffieldMappin StSheffieldSouth YorkshireS1 3JDUK

The effect of final hot rolling in the intercritical (α+γ) region on microstructure and properties is very specific to the individual processing conditions and the chemical composition of a steel.S460 is a plate steel processed in this *** reproduce at the laboratory scale,a multi-stage simulation was developed which included a high temperature austenite deformation and an isothermal *** effect of the applied cooling rate following intercritical deformation was *** 1K/s (typical industrial cooling) the microstructure was similar to the reference sample,but included an intragranular ferrite *** was due to differences in processing history,and considered to be linked to a larger prior austenite grain *** an accelerated cooling rate (15K/s),acicular ferrite formed on shear bands within the strained austenite *** scans have been completed to provide further information about the microstructures,with band contrast able to identify the pearlite phase at the slowest cooling *** is a starting point from which to focus on the ferrite morphologies.

关键词： intercritical deformation cooling rate laboratory simulation plate steel acicular ferrite

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Hospitalization for variceal hemorrhage in an era with more prevalent cirrhosis

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World j.urnal of Gastroenterology 2014年第32期20卷 11326-11332页

作者： Nicholas Lim Michael j.Desarno Steven D Lidofsky eric Ganguly Division of Gastroenterology and Hepatology University of Vermont College of Medicine Burlington VT 05401 United States Department of Biostatistics University of Vermont College of Medicine Burlington VT 05401 United States

AIM: To examine hospitalization rates for variceal hemorrhage and relation to cause of cirrhosis during an era of increased cirrhosis prevalence.

关键词： Varices Gastrointestinal bleeding Cirrhosis Hospitalization Portal hypertension

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Acute lower gastrointestinal bleeding from a dieulafoy lesion proximal to the anorectal j.nction post-orthotopic liver transplant

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World j.urnal of Gastroenterology 2006年第46期12卷 7547-7548页

作者： Wichian Apiratpracha j.n Kee Ho j.mes j.Powell eric M Yoshida British Columbia Transplant Society The University of British Columbia Vancouver BC Canada Division of Gastroenterology Department of Medicine The University of British Columbia Vancouver BC Canada Department of Surgery The University of British Columbia Vancouver BC Canada

A 67-year-old woman underwent an orthotopic liver transplantation for end stage liver disease secondary to chronic autoimmune hepatitis. She developed sudden massive hematochezia on post-operative day 23 with hemodynamic compromise. The source of hemorrhage was found at colonoscopy after careful irrigation and inspection to be a dieulafoy lesion situated j.st proximal to the anorectal j.nction. Hemostasis was achieved with epinephrine inj.ction and thermal coagulation.

关键词： Bleeding Anorectal Dieulafoy Rectum

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Complex peptide natural products: Biosynthetic principles, challenges and opportunities for pathway engineering

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Synthetic and Systems Biotechnology 2022年第1期7卷 631-647页

作者： Sebastian L.Wenski Sirinthra Thiengmag eric j.N.Helfrich Institute for Molecular Bio Science Goethe University Frankfurt60438Frankfurt am MainGermany LOEWE Center for Translational Biodiversity Genomics(TBG) 60325Frankfurt am MainGermany

Complex peptide natural products exhibit diverse biological functions and a wide range of physico-chemical *** a result,many peptides have entered the clinics for various *** main routes for the biosynthesis of complex peptides have evolved in nature:ribosomally synthesized and post-translationally modified peptide(RiPP)biosynthetic pathways and non-ribosomal peptide synthetases(NRPSs).Insights into both bioorthogonal peptide biosynthetic strategies led to the establishment of universal principles for each of the two *** universal rules can be leveraged for the targeted identification of novel peptide biosynthetic blueprints in genome sequences and used for the rational engineering of biosynthetic pathways to produce non-natural *** this review,we contrast the key principles of both biosynthetic routes and compare the different biochemical strategies to install the most frequently encountered peptide *** addition,the influence of the fundamentally different biosynthetic principles on past,current and future engineering ap-proaches is *** the different biosynthetic principles of both peptide biosynthetic routes,the arsenal of characterized peptide modifications encountered in RiPP and NRPS systems is largely *** continuous expansion of the biocatalytic toolbox of peptide modifying enzymes for both routes paves the way towards the production of complex tailor-made peptides and opens up the possibility to produce NRPS-derived peptides using the ribosomal route and vice versa.

关键词： Peptide natural products Non-ribosomal peptide synthetases Ribosomally synthesized and post-translationally modified peptides Biosynthesis Modification Engineering

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国际糖尿病足工作组:指南的制定和方法学(2023)——《国际糖尿病足工作组:糖尿病相关的足病预防与管理指南(2023)》的一部分

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感染、炎症、修复 2024年第1期25卷 72-79页

作者： Sicco A.Bus Matilde Monteiro-Soares Fran Game j.ap j.van Netten j.n Apelqvist Robert Fitridge eric Senneville Nicolaas C.Schaper on behalf of the IWGDF Editorial Board 朱虹何洁(译) 刘芳(审校) Amsterdam UMC University of AmsterdamDepartment of Rehabilitation MedicineAmsterdamthe Netherlands Amsterdam Movement Sciences program Rehabilitation&DevelopmentAmsterdamthe Netherlands Higher School of Health of the Portuguese Red Cross LisbonPortugal Department of Community Medicine Information and Health Decision Sciences(MEDCIDS)Faculty of MedicineUniversity of PortoPortoPortugal RISE@CINTESIS Faculty of MedicineOporto UniversityPortoPortugal Department of Diabetes and Endocrinology University Hospitals of Derby and Burton NHS Foundation TrustDerbyUK Department of Endocrinology University Hospital of MalmöSweden Discipline of Surgery The University of Adelaide and Vascular and Endovascular ServiceRoyal Adelaide HospitalAustralia Department of Infectious Diseases Gustave Dron HospitalTourcoingFrance Division of Endocrinology MUMC+CARIM and CAPHRI InstituteMaastrichtthe Netherlands 不详温州医科大学附属第一医院内分泌科浙江温州325000 上海交通大学医学院附属第一医院内分泌代谢科上海200080

糖尿病相关的足病是造成糖尿病患者经济负担和增加社会成本的主要原因之一。本指南以主要目标为导向,以循证医学为依据,且在全球得到合理实施。践行国际糖尿病相关的足病指南对于减轻患者经济负担和社会成本有着重要影响。国际糖尿病足... 详细信息

糖尿病相关的足病是造成糖尿病患者经济负担和增加社会成本的主要原因之一。本指南以主要目标为导向,以循证医学为依据,且在全球得到合理实施。践行国际糖尿病相关的足病指南对于减轻患者经济负担和社会成本有着重要影响。国际糖尿病足工作组(IWGDF)从1999年起开始发布并随后更新国际指南。2023年更新版指南相关推荐均基于推荐、评估、发展和评价分级(GRADE)系统,包括制定相关临床问题和重要结局,完成系统的文献系统综述和荟萃分析,完成评判表汇总,并且给予具体、明确、操作性强的推荐以及理论依据。本文阐述了《国际糖尿病足工作组:糖尿病相关的足病预防和管理指南(2023版)》(以下简称为指南)的制定过程。指南由7个部分组成,包括预防、糖尿病相关的足溃疡分类、减压、周围动脉病变、感染、创面愈合干预以及活动性夏科神经骨关节病,分别由7个独立的国际专家工作组编写。IWGDF编辑委员会对7个章节进行了整合和简化,形成IWGDF实践指南。指南中的每条推荐均经过IWGDF编辑委员会成员和相关领域的独立的国际专家审阅通过。本文是IWGDF指南的制定和方法学。我们相信,医务人员、公共卫生机构和政策制定者采用和实施2023年IWGDF指南,将会改善糖尿病相关的足病的预防和管理水平,从而减少全球该疾病患者和减轻该疾病引起的全球社会负担。

关键词：指南糖尿病糖尿病相关的足病方法学国际糖尿病足工作组

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