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Microscopic colitis:A large retrospective analysis from a health maintenance organization experience

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World Journal of Gastroenterology 2009年第25期15卷 3122-3127页

作者： Kevin T Kao Benito A Pedraza Amy C McClune David A Rios Yi-Qiong Mao Robert H Zuch Michael H Kanter Sony Wirio chris n conteas Department of Gastroenterology Kaiser PermanenteLos Angeles Medical Center Los Angeles California 90027United States Department of Internal Medicine Kaiser Permanente Los Angeles Medical Center Los Angeles California 90027 United States Department of Pathology Southern California Kaiser Permanente Medical Group California 90027 United States

AIM： To examine the demographic data on a large multi-ethnic population of patients with microscopic colitis （MC） in Southern California and to determine the association of MC with inflammatory bowel disease （IBD） and colorectal cancer. METHODS： All patients diagnosed with MC by co- Ionic biopsy from 1996-2005 were identified utilizing a pathology database. All biopsies were reviewed by experienced pathologists utilizing standard histologic criteria. Patients＇ medical records were reviewed and data regarding patient age, co-morbidities, sex, ethnic- ity, and medications were analyzed. An age- and sex- matched standard control group was also generated. Chi-square test was used to evaluate the associations of co-morbidities between lymphocytic colitis （LC）, col- lagenous colitis （CC） and the control group. RESULTS： A total of 547 cases of MC were identified, 376 patients with LC and 171 patients with CC. The fe- male/male ratio was 3：1 in CC and 2.7：1 in LC patients. Celiac disease （P 〈 0.001）, irritable bowel syndrome （IBS）（P 〈 0.001）, and thyroid diseases （P 〈 0.001） were found to have a higher occurrence in MC com- pared to the control group. no statistical differences in the occurrence of colorectal cancer, diabetes and IBD were found between the MC group and the control group. COnCLUSIOn： This is the largest group of patients with MC known to the authors that has been studied to date. Conditions such as celiac disease, IBS, and thyroid diseases were found to be related to MC. Fur- thermore, neither an increased risk of colorectal cancer nor IBD was associated with MC in this study.

关键词： Collagenous colitis Inflammatory bowel disease Lymphocytic colitis Microscopic colitis

Garnet fractionation,progressive melt loss and bulk composition variations in anatectic metabasites:Complications for interpreting the geodynamic significance of TTGs

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Geoscience Frontiers 2020年第3期11卷 745-763页

作者： Jillian Kendrick chris Yakymchuk Department of Earth and Environmental Sciences University of WaterlooWaterlooOntarioN2L 3G1Canada

Tonalite-trondhjemite-granodiorite(TTG) suites constitute a large proportion of the Archean geological record;however,the geodynamic processes that generated them,and Archean continental crust in general,remain a subject of *** concentrations and ratios of Sr,Y,La,Yb,nb,and Ta in TTGs are commonly used to determine the depth of melting of their metabasic *** trace element composition of melt produced by metabasic source rocks during anatexis is strongly affected by the presence and abundance of pressure-sensitive minerals,such as plagioclase(Sr-bearing),garnet(Y-and HREE-bearing),and rutile(nb-and Ta-bearing).Elevated Sr/Y and La/Yb ratios and low concentrations of nb and Ta in TTGs are generally considered to indicate melting at high pressures(≥2.0 GPa).The depth of melting is a key factor in determining the origin of TTGs as this provides critical information on the tectonic setting of their *** use phase equilibrium and trace element modelling to explore the effects of three potential influences on TTG trace element compositions:fractionation of trace elements into peritectic garnet cores,progressive melt loss from the source,and source bulk *** model three different compositions of Archean basalts along thermal gradients of 500℃/GPa,750℃/GPa,and 1000℃/*** models produce maj or and trace element melt compositions that are generally consistent with measured compositions of *** Sr/Y,La/Yb,nb,and Ta exhibit pressure-dependent behaviour,other factors also affect these *** fractionation causes Sr/Y and La/Yb to reach much greater values and in this scenario,the values also increase with increasing *** bulk composition has an effect in all scenarios and most strongly influences La/Yb,nb,and ***,these results show that Sr/Y,La/Yb,nb,and Ta can reach values generally considered to be indicative of high pressure melting at a range of P-T conditions including P <2.0 ***,trace ele

关键词： Archean Anatexis Trace element Phase equilibrium modelling Tectonics

Differential variable speed limits to improve performance and safety of car-truck mixed traffic on freeways

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 1003-1016页

作者： Anas Abdulghani chris Lee Department of Civil and Environmental Engineering University of WindsorWindsorON N9B 3P4Canada

This study develops a differential variable speed limit(DVSL)which assigns different speed limits for car and truck,and varies speed limits based on traffic *** proposed DVSL algorithm changes speed limits in real time based on truck percentage and occupancy immediately upstream of the ramp and the average speed of the control road sections upstream of the *** algorithm also considers spatial coordination of speeds,which gradually changes the speed limits in successive road sections upstream of the ramp when the severe congestion *** study tested the impacts of DVSL and three other speed limit strategies on delay and safety for a section of the Gardiner Expressway in Toronto,Canada using the VISSIM traffic simulation *** other strategies are 1)uniform speed limit(USL),2)differential speed limit for car and truck(DSL),and 3)USL&DSL(U&D)-i.e.,USL at low truck percentage and DSL at high truck *** was found that DVSL showed the lowest delays for both car and truck among the four *** is mainly because DVSL increased the spacing between vehicles in the right lane upstream of the on-ramp and facilitated vehicles’merging into the mainline *** was also found that DVSL showed the lowest likelihood of rear-end crash between the lead and following vehicles among the four *** study demonstrates that the proposed DVSL algorithm can better control car and truck speeds to reduce delay and improve safety of car-truck mixed traffic flow on freeways.

关键词： Variable speed limit Differential speed limit Truck Traffic performance Safety Freeway

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Factors associated with time to laparoscopic cholecystectomy for acute cholecystitis

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World Journal of Gastroenterology 2008年第7期14卷 1084-1090页

作者： chris n Daniak David Peretz Jonathan M Fine Yun Wang Alan K Meinke William B Hale Section of Gastroenterology Norwalk Hospital Norwalk CT United States Department of Internal Medicine Norwalk Hospital Norwalk CT United States Center for Outcomes Research and Evaluation Yale University/Yale New Haven Health System New Haven CT United States Department of Surgery Norwalk Hospital Norwalk CT United States

AIM: To determine patient and process of care factors associated with performance of timely laparoscopic cholecystectomy for acute cholecystitis. METHODS: A retrospective medical record review of 88 consecutive patients with acute cholecystitis was conducted. Data collected included demographic data, co-morbidities, symptoms and physical findings at presentation, laboratory and radiological investigations, length of stay, complications, and admission service (medical or surgical). Patients not undergoing cholecystectomy during this hospitalization were excluded from analysis. Hierarchical generalized linear models were constructed to assess the association of pre-operative diagnostic procedures, presenting signs, and admitting service with time to ***: Seventy cases met inclusion and exclusion criteria, among which 12 were admitted to the medical service and 58 to the surgical service. Mean ± SD time to surgery was 39.3 ± 43 h, with 87% of operations performed within 72 h of hospital arrival. In the adjusted models, longer time to surgery was associated with number of diagnostic studies and endoscopic retrograde cholangio-pancreatography (ERCP, P = 0.01) as well with admission to medical service without adjustment for ERCP (P nts undergoing both magnetic resonance cholangiopancreatography (MRCP) and computed tomography (CT) scans experienced the longest waits for surgery. Patients admitted to the surgical versus medical service underwent surgery earlier (30.4 ± 34.9 vs 82.7 ± 55.1 h, P ns (12% vs 58%, P nd shorter length of stay (4.3 ± 3.4 vs 8.1 ± 5.2 d, P nCLUSIOn: Admission to the medical service and performance of numerous diagnostic procedures, ERCP, or MRCP combined with CT scan were associated with longer time to surgery. Expeditious performance of ERCP and MRCP and admission of medically stable patients with suspected cholecystitis to the surgical service to speed up ti

关键词： Acute cholecystitis Laparoscopic cholecystectomy Endoscopic retrograde cholangiopancreatography Post-operative complications

Corundum formation by metasomatic reactions in Archean metapelite,SW Greenland:Exploration vectors for ruby deposits within high-grade greenstone belts

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Geoscience Frontiers 2018年第3期9卷 727-749页

作者： chris Yakymchuk Kristoffer Szilas Earth and Environmental Sciences University of Waterloo200 University Ave WestWaterlooOntario N2L 3G1Canada Geological Survey of Denmark and Greenland(GEUS) Oter Voldgade 101350 Copenhagen KDenmark

Corundum(ruby-sapphire) is known to have formed in situ within Archean metamorphic rocks at several localities in the north Atlantic Craton of Greenland. Here we present two case studies for such occurrences:(1) Maniitsoq region(Kangerdluarssuk), where kyanite paragneiss hosts ruby corundum, and(2)nuuk region(Stor?), where sillimanite gneiss hosts ruby corundum. At both occurrences, ultramafic rocks(amphibole-peridotite) are in direct contact with the ruby-bearing zones, which have been transformed to mica schist by metasomatic reactions. The bulk-rock geochemistry of the ruby-bearing rocks is consistent with significant depletion of SiO_2 in combination with addition of Al_2O_3, MgO, K_2O,Th and Sr relative to an assumed aluminous precursor metapelite. Phase equilibria modelling supports ruby genesis from the breakdown of sillimanite and kyanite at elevated temperatures due to the removal of SiO_2. The juxtaposition of relatively silica-and aluminum-rich metasedimentary rocks with low silica ultramafic rocks established a chemical potential gradient that leached/mobilized SiO_2 allowing corundum to stabilize in the former rocks. Furthermore, addition of Al_2O_3 via a metasomatic reaction is required, because Al/Ti is fractionated between the aluminous precursor metapelites and the resulting corundum-bearing mica schist. We propose that Al was mobilized either by complexation with hydroxide at alkaline conditions, or that Al was transported as K-Al-Si-O polymers at deep crustal *** three main exploration vectors for corundum within Archean greenstone belts are:(1) amphiboliteto granulite-facies metamorphic conditions,(2) the juxtaposition of ultramafic rocks and aluminous metapelite, and(3) mica-rich reactions zones at their interface.

关键词： Ultramafic rocks Kyanite Sillimanite Metasomatism Pseudosection Desilicification

A survey of high resolution image processing techniques for cereal crop growth monitoring

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Information Processing in Agriculture 2022年第2期9卷 300-315页

作者： Sanaz Rasti chris J.Bleakley n.M.Holden Rebecca Whetton David Langton Gregory O’Hare School of Computer Science University College DublinDublinIreland School of Agriculture and Food Science University College DublinDublinIreland School of Biosystems and Food Engineering University College DublinDublinIreland Origin Enterprises plc DublinIreland

This paper presents a survey of image processing techniques proposed in the literature forextracting key cereal crop growth metrics from high spatial resolution, typically proximalimages. The descriptive crop growth metrics considered are: crop canopy cover, aboveground biomass, leaf area index (including green area index), chlorophyll content, andgrowth stage. The paper includes an overview of relevant fundamental image processingtechniques including camera types, colour spaces, colour indexes, and image segmentation. The descriptive crop growth metrics are defined. Reference methods for groundtruth measurement are described. Image processing methods for metric estimation aredescribed in detail. The performance of the methods is reviewed and compared. The surveyreveals limitations in image processing techniques for cereal crop monitoring such as lackof robustness to lighting conditions, camera position, and self-obstruction. Directions forfuture research to improve performance are identified.

关键词： Crop canopy cover Above ground biomass Leaf area index Chlorophyll content Growth stage Cereal image processing

Cadmium,chromium,copper,iron,lead,mercury,nickel,and zinc in freshwater fish:Assessing trophic transfer using stable isotope ratios ofδ^(15)n andδ^(13)C

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Journal of Environmental Sciences 2023年第6期128卷 250-257页

作者： Chester Lau X.chris Le Department of Chemistry Faculty of ScienceUniversity of AlbertaAlberta T6G 2G2Canada Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaAlberta T6G 2G3Canada

Introduction The health benefits of consuming aquatic organisms are clear,given their high protein count,low saturated fats,and low cholesterol ***,in particular,contains valuable nutrients(e.g.,omega-3 polyunsaturated fats),vitamins,essential elements,and is therefore considered an important part of a balanced human *** is a major seafood producer,accounting for 58%of global production in 2018(Crona et al.,2020).China is the largest seafood consuming country in the world,with consumption rates steadily *** the 1978 Chinese economic reform,the amount of seafood consumed per capita in China increased from 5 kg per capita in 1980 to 41 kg in 2015(Zhang et al.,2021).By 2030,the overall amount of fish consumption will likely exceed the amount of fish production in China.

关键词： Aquatic environment Bioaccumulation Biomagnification Fish consumption Growth dilution effect Metal contamination Stable isotope ratio Trace elements Trophic levels

Optical DE/MUX Components for Datacomunication Applications

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光学学报 2003年第S1期23卷 617-618页

作者： Ian H White Richard V Penty Kevin A Williams chris n Morgan Cambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UKCambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UKCambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UKCambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UK

This paper reviews the potential for WDM systems to be implemented within datacommunication systems, and indicates future network functions. Spectral and temporal multiplexing functions are reviewed, with particular f... 详细信息

关键词： for be in Optical DE/MUX Components for Datacomunication Applications WDM

Investigation of the heat distribution in dry friction systems during fade and recovery using fiber-optic sensing and infrared technology

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Friction 2022年第3期10卷 422-435页

作者： Albert ALBERS Thomas KLOTZ chris FInK Sascha OTT IPEK–Institute of Product Engineering Karlsruhe Institute of TechnologyBaden Wurttemberg 76131Germany

The design of dry-running friction pairings and systems determines not only their installation space and costs,but also their reliability under critical load conditions,for example in emergencies,in the case of faults,and in the event of *** knowledge of the contact pattern is highly important for the development of clutches and brakes,the contact-related measurement of the temperature of these systems has not yet been solved in a satisfactory *** its importance,the temperature distribution has only been measured in a few ***,temperature measurements of complete clutches and brakes are carried out using thermocouples *** this study,a new innovative test setup is *** setup is able to measure the heat distribution of the lining and the steel disk of a brake with high spatial resolution by means of fiber optic sensing technology and *** a novelty,it enables measurement of the heat distribution and allows to correlate it with the fade and recovery *** to the expectations,the contact pattern is heterogeneous in circumferential *** causes are discussed using simulation *** with surface analysis,the new setup contributes to the investigation of the causes of fade and recovery.

关键词： dry-running clutch and brake fade and recovery high-resolution spatial temperature distribution measurement