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Time-lapse 3-D Seismic Wave Simulation via the Generalized Multiscale Finite Element Method

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Communications in Computational Physics 2020年第6期28卷 401-423页

作者： Yongchae Cho Richard l.Gibson,jr. Hyunmin Kim Mikhail Artemyev Yalchin Efendiev Shell International Exploration&Production Inc. 150 N Dairy Ashford RoadHoustonTX 77079USA Department of Geology&Geophysics Texas A&M UniversityCollege StationTexas 77843-3115USA Shell Exploration&Production Company 701 Poydras StreetNew OrleansLA 70139USA Arista Networks DublinIreland Department of Mathematics Texas A&M UniversityCollege StationTexas 77843-3368USA Multiscale Model Reduction laboratory North-Eastern Federal UniversityYakutskRepublic of Sakha 677980Russia

Numerical solution of time-lapse seismic monitoring problems can be challenging due to the presence of finely layered *** wave modeling using fine layered meshes also adds more computational *** approaches such as finite difference and finite element methods may be prohibitively expensive if the whole domain is discretized with the cells corresponding to the grid in the reservoir subdomain.A common approach in this case is to use homogenization techniques to upscale properties of subsurface media and assign the background properties to coarser grid;however,inappropriate application of upscaling might result in a distortion of the model,which hinders accurate monitoring of the fluid change in *** this work,we instead investigate capabilities of a multiscale method that can deal with fine scale heterogeneities of the reservoir layer and more coarsely meshed rock properties in the surrounding domains in the same *** address the 3-D wave problems,we also demonstrate how the multiscale wave modeling technique can detect the changes caused by fluid movement while the hydrocarbon production activity proceeds.

关键词： Fluid simulation time lapse Generalized multiscale finite element elastic wave

Estimating Trade Mis-invoicing from China:2000-2005

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China & World Economy 2008年第2期16卷 82-92页

作者： Edsel l.Beja jr. Deputy Director Ateneo Center for Economic Research and DevelopmentAteneo de Manila UniversityQuezon CityPhilippines

An examination of available data reveals large trade misinvoicing between China and its trade partners. The analysis finds a net trade misinvoicing of US$287.6bn between 2000 and 2005, while the full magnitude of unrecorded trade is estimated at US$1.4tn. China needs to establish more effective management of its international trade flows. At the same time, the international community needs to provide more effective governance mechanisms to address trade misinvoicing.

关键词： intemational trade flows policy challenges for China trade misinvoicing

Photoluminescent Tb^(3+)-based metal-organic framework as a sensor for detection of methanol in ethanol fuel

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Journal of Rare Earths 2019年第3期37卷 225-231页

作者： Ramon R.F.Fonseca Rafael D.l.Gaspar Ivo M.Raimundo jr. Priscilla P.luz Department of Chemistry Federal University of Espírito Santo Institute of Chemistry University of Campinas

The sensing capability of a Tb^(3+)-metal-organic framework, based on its photoluminescence, was used for detection of methanol in ethanol fuel. It was synthesized using terbium and trimesic acid as a metal ion center and ligand, respectively. Powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy were employed to characterize the synthesized MOF-76 structural features. According to the results, MOF-76 was successfully obtained with minor synthetic modification and its activated form(named TbTMA) was tested as a sensor for methanol. Tb^(3+) luminescence intensity increases as the methanol concentration in ethanol fuel also increases and the water content does not affect this response. Our findings indicate TbTMA as an appropriate sensor for evaluating ethanol fuel adulteration by methanol addition above the allowed limit.

关键词： lanthanide Metal-organic frameworks luminescence Ethanol fuel Sensor Adulteration

Nitrate reduction capacity of the oral microbiota is impaired in periodontitis:potential implications for systemic nitric oxide availability

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International Journal of Oral Science 2024年第1期16卷 52-61页

作者： Bob T.Rosier William Johnston Miguel Carda-Diéguez Annabel Simpson Elena Cabello-Yeves Krystyna Piela robert Reilly Alejandro Artacho Chris Easton Mia Burleigh Shauna Culshaw Alex Mira Department of Genomics and Health FISABIO FoundationCenter for Advanced Research in Public HealthValenciaSpain Department of Biological and Biomedical Sciences Glasgow Caledonian UniversityGlasgowUK Oral Sciences University of Glasgow Dental SchoolSchool of MedicineDentistry and NursingCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowUK Sport and Physical Activity Research Institute University of the West of ScotlandBlantyreScotland Instituto de Biomedicina de Valencia Consejo Superior de Investigaciones Científicas(IBV-CSIC)ValenciaSpain CIBER Center for Epidemiology and Public Health MadridSpain

The reduction of nitrate to nitrite by the oral microbiota has been proposed to be important for oral health and results in nitric oxide formation that can improve cardiometabolic conditions. Studies of bacterial composition in subgingival plaque suggest that nitrate-reducing bacteria are associated with periodontal health, but the impact of periodontitis on nitrate-reducing capacity(NRC)and, therefore, nitric oxide availability has not been evaluated. The current study aimed to evaluate how periodontitis affects the NRC of the oral microbiota. First, 16S rRNA sequencing data from five different countries were analyzed, revealing that nitratereducing bacteria were significantly lower in subgingival plaque of periodontitis patients compared with healthy individuals(P ll five datasets with n = 20–82 samples per dataset). Secondly, subgingival plaque, saliva, and plasma samples were obtained from 42 periodontitis patients before and after periodontal treatment. The oral NRC was determined in vitro by incubating saliva with 8 mmol/l nitrate(a concentration found in saliva after nitrate-rich vegetable intake) and compared with the NRC of 15healthy individuals. Salivary NRC was found to be diminished in periodontal patients before treatment(P lthy levels 90 days post-treatment. Additionally, the subgingival levels of nitrate-reducing bacteria increased after treatment and correlated negatively with periodontitis-associated bacteria(P l treatment on the baseline saliva and plasma nitrate and nitrite levels was found, indicating that differences in the NRC may only be revealed after nitrate intake. Our results suggest that an impaired NRC in periodontitis could limit dietary nitrate-derived nitric oxide levels, and the effect on systemic health should be explored in future studies.

关键词： impaired intake nitrate

Scanning-slit topography in patients with keratoconus

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International Journal of Ophthalmology(English edition) 2017年第11期10卷 1686-1692页

作者： lászló Módis jr. Gábor Németh Eszter Szalai Zsuzsa Flaskó Berthold Seitz Department of Ophthalmology University of Debrecen Medical and Health Science Center Debrecen 4032 Hungary Borsod-Abau-Zemplen County Hospital and University Teaching Hospital Miskolc 3526 Hungary Department of Ophthalmology Homburg Kemtoconus Center University of Saarland Homburg/Saar 66424 Germany

AIM： To evaluate the anterior and posterior corneal surfaces using scanning-slit topography and to determine the diagnostic ability of the measured corneal parameters in ***： Orbscan II measurements were taken in 39 keratoconic corneas previously diagnosed by corneal topography and in 39 healthy eyes. The central minimum, maximum, and astigmatic simulated keratometry（K） and anterior axial power values were determined. Spherical and cylindrical mean power diopters were obtained at the central and at the steepest point of the cornea both on anterior and on posterior mean power maps. Pachymetry evaluations were taken at the center and paracentrally in the 3 mm zone from the center at a location of every 45 degrees. Receiver operating characteristic（ROC） analysis was used to determine the best cut-off values and to evaluate the utility of the measured parameters in identifying patients with ***： The minimum, maximum and astigmatic simulated K readings were 44.80±3.06 D, 47.17±3.67 D and 2.42±1.84 D respectively in keratoconus patients and these values differed significantly（P〈0.0001 for all comparisons） from healthy subjects. For all pachymetry measurements and for anterior and posterior mean power values significant differences were found between the two groups. Moreover, anterior central cylindrical power had the best discrimination ability（area under the ROC curve=0.948）.CONClUSION： The results suggest that scanning-slit topography and pachymetry are accurate methods both for keratoconus screening and for confirmation of the diagnosis.

关键词： keratoconus Orbscan topography pachymetry

legume Green Manure and Intercropping for High Biomass Sorghum Production

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Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season legumes Used in a Green Manure-Forage Cropping System

Agricultural Sciences（农业科学） 2024年第6期 605页

作者： Clark B.Neely Francis M.Rouquette jr. Cristine l.S.Morgan Frank M.Hons William l.Rooney Gerald R.Smith

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It’s a Matter of Time

Agricultural Sciences（农业科学） 2024年第3期 333页

作者： Clark B.Neely Francis M.Rouquette jr. Cristine l.S.Morgan Frank M.Hons William l.Rooney Gerald R.Smith

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Journal of Modern Physics 2015年第6期6卷 758-771页

作者： robert A. Barrett jr. Honolulu HI USA

This paper describes a universe consisting only of time dilation and compares it to the one which we observe.

关键词： Time Dilation Gravity light Electricity Magnetism

Impact of a physician-supervised exercise-nutrition program with testosterone substitution in partial androgen-deficient middle-aged obese men

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Journal of Geriatric Cardiology 2011年第4期8卷 201-206页

作者： Ernst R Schwarz robert D Willix jr Cenegenics Education and Research Foundation Las Vegas and Heart Institute of Southern CaliforniaBeverly Hills348 S Oakhurst DrBeverly HillsCA 90212USA

Background Partial androgen deficiency syndrome in the aging male is associated with signs of aging such as a development of abdominal obesity,sexual dysfunction,increase body fat,weight gain and the development of cardiac *** We assessed the outcome of a commercially available physician supervised nutrition and exercise program with concomitant testosterone replacement therapy in middle age obese men with partial androgen deficiency in order to reduce cardiac risks *** Fifty-six self referred men without diabetes mellitus,hypertension,or cardiovascular disease(ages 52.3±7.8 years)were randomly selected from a large *** weight,body fat composition,fasting glucose,hemoglobin A1c and fasting lipid levels,as well as free and total testosterone levels were *** patients were assessed and followed 6–18 months after initiation of the *** program consisted of a low glycemic load balanced nutrition diet,a recommended structured daily exercise program of 30–60 minutes,as well as once to twice weekly intramuscular testosterone injections(113.0±27.8 mg).Results At follow up,weight was reduced from 233.9±30.0 pounds(lbs)to 221.3±25.1 lbs(Pl body fat was 27.1%±5.2%vs.34.3%±5.7%at baseline(Plucose was reduced from 95.3±14.4 mg/dl to 87.5±12.6 mg/dl(Pl cholesterol was reduced from 195.4±33.0 mg/dl to 172.7±35.0 mg/dl(Plinically significant adverse events were *** Testosterone replacement therapy in middle aged obese men with partial androgen deficiency appeared safe and might have promoted the effects of a weight reduction diet and daily exercise program as long as an adequate physician supervision and follow up was *** combination therapy significantly reduced coronary risk factors such as glucose intolerance and hyperlipidemia.

关键词： aging heart disease androgen deficiency testosterone