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碎屑岩盆地充填过程的实用动态模拟

国外油气勘探 1997年第3期9卷 284-302页

作者： Cedric m.griffiths Frode Hadler-Jacobsen 刘力江汉石油学院基础科学系物理教研室

在过去二十年内人们已经开发出种种定量的计算机正演地层模型。这些正演模型在石油工业中的实际应用局限于少数几种情况。其原因部分是从现有数据导出实际输入参数的一些具体困难,部分是对这些结果的预测值尚存疑虑。在本文中,我们讨论... 详细信息

在过去二十年内人们已经开发出种种定量的计算机正演地层模型。这些正演模型在石油工业中的实际应用局限于少数几种情况。其原因部分是从现有数据导出实际输入参数的一些具体困难,部分是对这些结果的预测值尚存疑虑。在本文中,我们讨论了两个商用的"定量动力地层学"(QDS)模拟软件包(SEDPAK和 PHIL^(Tm))在 Outer moray Firth 的古新世地层序列中的应用。我们展示了三维年代地层学是如何被用来确定二维模型的定量输入参数。高分辨率、持续时间短的"时间体"(Chronosomes)(0.1～200ka)的形态函数是推导相对海平面曲线、相对沉积速率、粒级分布以及沉降史的关键。当然,这些参数一般就是我们希望用QDS模型在远离钻井控制区域所要预测的特性。因此,QDS的作用也就是从预测转变为对由三维年代地层学所作出的预测假设在沉积学上的合理性进行检验。当然,我们还必须假定QDS模型本身在沉积学上是言之成理的。通常被掩盖了的层序地层学问题,诸如沉降与沉积脉动的相对时间,在QDS模型中是至关重要的。学会根据构造或气候事件诱发的沉积脉动,而不是根据更常见的假定的稳定沉积作用来控制这些变量,是开发动态层序地层学模型的另一个实际利益。

关键词：盆地模拟孔隙度碎屑岩地层充填油气勘探

Adult neurogenesis from reprogrammed astrocytes

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Neural Regeneration Research 2020年第6期15卷 973-979页

作者： Brian B.griffiths Anvee Bhutani Creed m.Stary Department of Anesthesiology Pain & Perioperative Medicine Stanford University School of Medicine

The details of adult neurogenesis,including environmental triggers,region specificity,and species homology remain an area of intense *** or halting age-related cognitive dysfunction,or restoring neurons lost to disease or injury represent just a fraction of potential therapeutic *** neurons can derive from stem cells,pluripotent neural progenitor cells,or non-neuronal glial cells,such as *** must be epigenetically"reprogrammed"to become neurons,which can occur both naturally in vivo,and via artificial exogenous *** neural progenitor cells are localized to a few neurogenic zones in the adult brain,astrocytes populate almost every brain *** this review,we will summarize recent research into neurogenesis that arises from conversion of post-mitotic astrocytes,detail the genetic and epigenetic pathways that regulate this process,and discuss the possible clinical relevance in supplementing stem-cell neurogenic therapies.

关键词： astrocyte brain dedifferentiation development disease glia injury neurogenesis

Gut microbiome in primary sclerosing cholangitis:A review

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World Journal of Gastroenterology 2020年第21期26卷 2768-2780页

作者： Rebecca Little Eytan Wine Binita m Kamath Anne m.griffiths Amanda Ricciuto Division of Gastroenterology Hepatology and NutritionThe Hospital for Sick ChildrenTorontoON M5G 1X8Canada Division of Pediatric Gastroenterology and Nutrition 7-142H Katz Group–Rexall CentreUniversity of AlbertaEdmontonAB T6G 1C9Canada

Primary sclerosing cholangitis(PSC)is a chronic cholestatic liver disease characterized by biliary inflammation and *** of the pathogenesis of PSC in light of its association with inflammatory bowel disease(IBD)and the“gut-liver”axis is an emerging area of interest.A growing number of studies have begun to elucidate the role of the gut microbiota,its metabolites and its influence on host immune responses in the development of PSC and *** of the fecal microbiota have highlighted enriched levels of certain species,including Veillonella,Streptococcus and Enterococcus,among others.A heightened immune response to enteric dysbiosis and bacterial translocation have also been *** example,Klebsiella pneumoniae strains derived from gnotobiotic mice transplanted with PSC-IBD microbiota were found to induce pore formation in human intestinal epithelial cells and enhanced Th17 *** microbes have additionally been hypothesized to be implicated in PSC pathogenesis through their role in the synthesis of various metabolites,including bile acids(BAs),which function as signaling molecules with important gut and hepatic *** expanded knowledge of the gut microbiome as it relates to PSC offers critical insight into the development of microbe-altering therapeutic interventions,such as antibiotics,nutritional interventions and fecal microbial *** of these have already shown some preliminary evidence of *** exciting progress in the field,much work remains to be done;areas that are particularly lacking include functional characterization of the microbiome and examination of pediatric *** this review,we summarize studies that have investigated the microbiome in PSC and PSC-IBD as well as putative mechanisms,including the potential role of metabolites,such as *** then briefly review the evidence for interventions with microbe-altering properties for treating PSC.

关键词： Bile acids Colitis Inflammatory bowel disease microbiome microbiota Primary sclerosing cholangitis

Assessing disease activity using the pediatric Crohn’s disease activity index:Can we use subjective or objective parameters alone?

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World Journal of Gastroenterology 2021年第30期27卷 5100-5111页

作者： Amy Grant Trudy Lerer Anne m.griffiths JS Hyams Anthony Otley Division of Pediatrics IWK HealthHalifaxNS B3K6R8Canada Division of Research Connecticut Children's Medical CenterHartfordCT 06106United States Division of Gastroenterology Hepatology and Nutrition The Hospital for Sick ChildrenTorontoON M5G1X8Canada Division of Gastroenterology Connecticut Children's Medical CenterHartfordCT 06106United States Division of Pediatrics Dalhousie UniversityHalifaxNS B3H4C3Canada

BACKGROUND The pediatric Crohn’s disease activity index(PCDAI)is used as a standard tool to assess disease activity in clinical trials for pediatric Crohn’s *** To examine which items on the PCDAI drive assessment of disease activity,and how subgroups of subjective and objective items reflect change in disease state over *** Selective raw data from three prospectively collected datasets were combined,including 703 children with full PCDAI data at baseline,at 3-mo(Q1,n=670),and 1-year(Q4,n=474).Change in individual PCDAI scores from baseline to Q1 and to Q4 were examined using the non-weighted *** Abdominal pain,well-being,weight,and stooling had the highest change scores over *** indicators including albumin,abdominal exam,and height velocity *** scores for well-being and abdominal exam did not explain significant variance at Q1 but were significant predictors at Q4(Pms predicted less variance(18%and 22%)on total PCDAI scores at Q1 and Q4 compared to the full PCDAI,or a composite scale(both 32%)containing significant *** Although subjective items on the PCDAI change the most over time,the full PCDAI or a smaller composite of items including a combination of subjective and objective components classifies disease activity better than a subgroup of either subjective or objective items *** on subjective or objective items as stand-alone proxies for disease activity measurement could result in misclassification of disease state.

关键词： Crohn’s disease Pediatric Crohn’s disease activity index Patient reported outcome measurement Disease activity Clinical trials Pediatric

Calculation of reservoir capacity loss due to sediment deposition in the muela reservoir,Northern Lesotho

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International Soil and Water Conservation Research 2017年第2期5卷 130-140页

作者： Liphapang Khaba James Andrew griffiths Water and Environmental Engineering School of the Built EnvironmentLerotholi PolytechnicMoshoeshoe RoadP.O.Box 16Maseru 100Lesotho Department of Geographical Sciences University of Nottingham Ningbo China199 Taikang East RoadNingbo 315100ZhejiangChina

Bathymetry survey records of the muela Reservoir in norther Lesotho were obtained from the Lesotho Highlands Development Authority(LHDA)with the aim of identifying reservoir storage apacity loss due to sediment deposition,between 1985 and *** this purpose,data from eight surveys completed between 1985 and January 2015 were analyzed to quantify bathymetric change between each *** interpolation methods(inverse distance weighting Kriging,natural neighbor,and spline),were used to create digital terrain models from each survey *** addition,a triangulated irregular network(TIN)surface was created from each *** average reservoir storage capacity loss of 15,400 m^(3)/year was determined across the whole per iod between 1985 and early 2015,based on *** the results indicate high inter-annual variability in the rate of reservoir capacity reduction,consideration of errors in the surveying and reservoir volumetric calculation methods suggest that rates of reservoir volume reduction can vary between 11,400 m/year and 18,200 m/year.

关键词： Reservoir Bathymetry Sedimentation Lesotho

Functionalised Polymers by Surface modification

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复旦学报（自然科学版） 2005年第5期44卷 772-773页

作者： Jon-Paul griffiths m. G. moloney Chemistry Research Laboratory Mansfield Rd University of OxfordOX 3TAUnited KingdomChemistry Research Laboratory Mansfield Rd University of OxfordOX 3TAUnited Kingdom

Surface-active polymers are of substantial importance in many diverse aspects of modern technology, with applications ranging from solid phase chemical synthesis related to drug discovery and chemical catalysis to biocompatible/bioactive medical implants and prostheses, and to surface-modified fabrics. Whilst there are a number of existing physical (e. g. corona or plasma discharge, ion beam irradiation[1] ) and chemical (e. ***, oxidation, chlorination, acylation and quaternisation[2-4]) methods for the surface modification of polymers, the frequent requirement for significant infrastructure, harsh reaction conditions, and limitation to specific polymer types (e. g. polybutadiene[5] ), which must possess suitable chemical functionality capable of direct modification, led us to consider alternative chemical methods. Desirable was an alternative that would be amenable to a large range of polymers, permitting direct chemical modification under mild conditions and using inexpensive reagents.

关键词：聚合体表面活性表面修复碳烯合成方法

Identification of Differentially Senescing mutants of Wheat and Impacts on Yield,Biomass and Nitrogen Partitioning

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Journal of Integrative Plant Biology 2012年第8期54卷 555-566页

作者： Adinda P.Derkx Simon Orford Simon griffiths m.John Foulkes malcolm J. Hawkesford Plant Biology and Crop Science Department Rothamsted ResearchHarpendenHertfordshireAL5 2JQUK Division of Plant&Crop Sciences School of BiosciencesUniversity of NottinghamSutton Bonington CampusNr LoughboroughLE12 5RDUK John Innes Centre Norwich Research ParkColneyNorwich NR4 7UHUK

Increasing photosynthetic capacity by extending canopy longevity during grain filling using slow senescing stay-green genotypes is a possible means to improve yield in wheat. Ethyl methanesulfonate （EmS） mutated wheat lines （Triticum aestivum L. cv. Paragon） were screened for fast and slow canopy senescence to investigate the impact on yield and nitrogen partitioning. Stay-green and fast-senescing lines with similar anthesis dates were characterised in detail. Delayed senescence was only apparent at higher nitrogen supply with low nitrogen supply enhancing the rate of senescence in all lines. In the stay-green line 3 （SG3）, on a whole plant basis, tiller and seed number increased whilst thousand grain weight （TGW） decreased; although a greater N uptake was observed in the main tiller, yield was not affected. In fast-senescing line 2 （FS2）, yield decreased, principally as a result of decreased TGW. Analysis of N-partitioning in the main stem indicated that although the slow-senescing line had lower biomass and consequently less nitrogen in all plant parts, the proportion of biomass and nitrogen in the flag leaf was greater at anthesis compared to the other lines; this contributed to the grain N and yield of the slow-senescing line at maturity in both the main tiller and in the whole plant. A field trial confirmed senescence patterns of the two lines, and the negative impact on yield for FS2 and a positive impact for SG3 at low N only. The lack of increased yield in the slow-senescing line was likely due to decreased biomass and additionally a possible sink limitation.

关键词： Wheat senescence stay-green grain-filling yield nitrogen.

Influences of harvester and weather conditions on field loss and milling quality of rough rice

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International Journal of Agricultural and Biological Engineering 2017年第4期10卷 216-223页

作者： Ragab Khir griffiths Atungulu Ding Chao Zhongli Pan Department of Biological and Agricultural Engineering University of CaliforniaDavisCA 95616USA Department of Agricultural Engineering Faculty of AgricultureSuez Canal UniversityIsmailiaEgypt Department of Food Science University of ArkansasFayettevilleAR 72701USA College of Food Science and Engineering Nanjing University of Finance and EconomiesNanjingJiangsu 210023China Healthy Processed Foods Research Unit Western Regional Research CenterAgricultural Research ServiceU.S.Department of AgricultureAlbanyCA 94710USA

A better understanding of factors affecting field losses and milling quality during harvest is needed to improve the economic value of *** main objective of this study was to evaluate the impact of harvester header,harvester type,and weather conditions on field loss and milling quality of rough *** popular harvesters equipped with different headers:John Deere 9870 with header D60-S,John Deere 9860 with header D972-S,Hardy,and John Deere 9770 with stripper header were evaluated in this *** header and total field losses of rice were evaluated for each harvester under regular,rainy and windy weather *** were conducted in a rice field cultivated with medium grain rice,variety m206,at Grimes,*** rice yield(TRY),head rice yield(HRY)and whiteness index(WI)were examined to evaluate the effect of weather conditions on milling *** obtained results revealed that the rice field loss was affected by harvester header and type,and weather *** the conventional headers,D60-S significantly reduced the rice loss compared to the D972-S and the *** with John Deere 9860 resulted in significant header and field loss compared to other tested *** average loss increased from 236.2 kg/hm^(2)and 445.2 kg/hm^(2)under regular condition to 711.1 kg/hm^(2)and 907.9 kg/hm^(2)under windy condition for John Deere 9870 and John Deere 9860,*** corresponding loss percentages increased from 2.6%and 4.9%to 7.9%and 10.1%.HRY was significantly affected by weather condition at harvest ***,the weather condition had no significant effect on TRY and *** minimize the rice field loss and obtain good milling quality,commercial rice harvesting during regular weather conditions is important.A proper combination of harvester type and header could be vital for reducing the rice loss.

关键词： rice harvesters field loss weather conditions milling quality harvester header

Potential groundwater recharge zones within New Zealand

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Geoscience Frontiers 2019年第3期10卷 1065-1072页

作者： Shailesh Kumar Singh malte Zeddies Ude Shankar George A.griffiths National Institute of Water and Atmospheric Research

Water resources in New Zealand are not evenly distributed across the country which makes it difficult to adequately allocate the use of water resources in every basin. Groundwater is a fundamental water resource in New Zealand for agricultural, industrial and domestic use. Detailed knowledge regarding groundwater recharge potential is a pre-requisite for sustainable groundwater management, including the assessment of its vulnerability to contamination by pollutants. In this study, a comprehensive GIS approach was used to map the potential groundwater recharge zones across New Zealand. National data sets of lithology, slope, aspect, land use, soil drainage and drainage density were converted to raster data sets with a spatial resolution of 500 m x 500 m and superimposed to derive groundwater potential zones. The resultant maps demonstrate that the potential is low in urban and mountainous areas, such as the Southern Alps, whereas the highest potential can be found in regions with large lakes and in the lower elevation plains areas, where Quaternary sediments prevail. The resulting maps can be used to identify areas of high nutrient leaching in zones where high groundwater recharge potential exists.

关键词： GIS Potential groundwater recharge map New Zealand