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A Study of Fluid Flow in Sediments and the Effect of Tidal Pumping

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Journal of Earth Science 2017年第5期28卷 842-847页

作者： Paulo Waltrich john Whitehead richard Hughes Karsten thompson Department of Petroleum Engineering Louisiana State University

Offshore drilling and production operations can result in spills or leaks of hydrocarbons into seabed sediments, which can potentially contaminate these sediments with oil. If this oil later mi- grates to the water surface it has the potential for negative environmental impacts. For proper contin- gency planning and to avoid larger consequences in the environment, it is essential to understand me- chanisms and rates for hydrocarbon migration from oil containing sediments to the water surface as well as how much will remain trapped in the sediments. It is believed that the amount of oil transported out of the sediment can be affected by tidal pumping, a common form of subterranean groundwater dis- charge （SGD）. However, we could find no study experimentally investigating the phenomenon of fluid flow in subsea sediments containing oil and the effects of tidal pumping. This study presents an experi- mental investigation of tidal pumping to determine if it is a possible mechanism that may contribute to the appearance of an oil sheen on the ocean surface above a sediment bed containing oil. An experimen- tal apparatus was constructed of clear PVC pipe allowing for oil migration to be monitored as it flowed out of a sand pack containing oil, while tidal pressure oscillations were applied in three different man- ners. The effect of tidal pumping was simulated via compression of air above the water （which simulated the increasing static head from tidal exchange）. Experimental results show that sustained oil release oc- curred from all tests, and tests with oscillating pressure produced for longer periods of time. Further- more, the experimental results showed that the oil migration rate was affected by grain size, oil satura- tion, and oscillation wave type. In all oscillating experiments the rate and ultimate recovery was less than the comparable static experiments. For the conditions studied, the experimental results indicate that with an oscillating pressure on top of a

关键词： tidal pumping oil migration sediments oil release rate.

Chemo-dynamical modelling with Schwarzschild's method

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Research in Astronomy and Astrophysics 2018年第12期18卷 1-8页

作者： richard john Long Shude Mao National Astronomical Observatories Chinese Academy of Sciences Jodrell Bank Centre for Astrophysics School of Physics and Astronomy The University of Manchester Physics Department and Tsinghua Centre for Astrophysics Tsinghua University

We extend Schwarzschild’s dynamical modelling method to model absorption line strength data as well as the more usual luminosity and kinematic *** approach draws on earlier published work by the first author with the Syer & Tremaine made-to-measure(M2M) dynamical modelling method and uses similar ideas to create a chemo-Schwarzschild *** apply our extended Schwarzschild method to the same four early type galaxies(NGC 1248, NGC 3838, NGC 4452,NGC 4551) as the chemo-M2M work, and are able to recover successfully the 2D absorption line strength for the three lines we model(Hβ, Fe5015, Mg b).We believe that this is the first time Schwarzschild’s method has been used in this *** techniques developed can be applied to modelling other aspects of galaxies, for example age and metallicity data coming from stellar population modelling, and are not specific to absorption line strength data.

关键词： galaxies:abundances galaxies:formation galaxies:individual(NGC 1248,NGC 3838,NGC 4452,NGC 4551) galaxies:kinematics and dynamics galaxies:structure methods:numerical

A Method of Characterizing Radio Signal Space for Wireless Device Localization

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Tsinghua Science and Technology 2015年第4期20卷 385-408页

作者： john-Austen Francisco richard P.Martin Department of Computer Science Rutgers University

In this work we present a novel approach for describing radio signal spaces for localization algorithms. We first introduce a new metric, the Discretely Distributed Log-H61der Metric （DDLHM）. The DDLHM is designed to characterize the type and degree of signal distortion relative to Iognormal signal-to-distance path models. We first show how the DDLHM can describe and discriminate distortions in an exhaustive set of synthetic signal spaces. We then determine a reduced set of maximally diagnostic distortion parameters. Using only 4% of the maximal set of DDLHMs, we found the reduced set matches with an acceptable degree of error 95% of the time. Using the synthetic reduced set, we characterized a variety of wireless localization algorithms＇ behaviors to attenuation, bias, and multipath. We found algorithms made much different tradeoffs between best case and average case error. We then use the DDLHM to identify distortion types in three different physical environments using measured 802.11 signal strengths, and predict the positioning performance of several localization algorithms. Our approach predicts average localization error to within 2 meters of the observed average error.

关键词： radio propgation 802.11 WiFi

Characteristics,management and response to alteplase in China versus non-China participants of the ENCHANTED trial

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Stroke & Vascular Neurology 2017年第2期2卷 53-58页

作者： Lily Song Xia Wang thompson Robinson richard I Lindley Hisatomi Arima Pablo M Lavados Xiaoying Chen john Chalmers Craig S Anderson The George Institute for Global Health at Peking University Health Science Center BeijingChina Department of Neurology 85 Hospital of People’s Liberation ArmyShanghaiChina The George Institute for Global Health The University of New South WalesSydneyAustralia Department of Cardiovascular Sciences and NIHR Biomedical Research Unit for Cardiovascular Sciences University of LeicesterLeicesterUK Department of Preventive Medicine and Public Health Faculty of MedicineFukuoka UniversityFukuokaJapan Clínica Alemana de Santiago Universidad del DesarrolloConcepciónChile Departamento de Ciencias Neurológicas Facultad de MedicinaUniversidad de ChileConcepciónChile Neurology Department Royal Prince Alfred HospitalSydneyAustralia

Background The characteristics of patients with acute ischaemic stroke(AIS)and their management vary across regions,which may influence *** examined for differential patterns of outcome between China and non-China participants of the ENhanced Control of Hypertension And Thrombolysis strokE stuDy(ENCHANTED),which tested different alteplase doses in *** ENCHANTED was an international,multicentre,open,blinded-endpoint trial of the effects of low-dose(0.6 mg/kg)versus standard-dose(0.9 mg/kg)intravenous alteplase on 90-day disability outcomes and symptomatic intracerebral haemorrhage(sICH)in 3310 patients with *** Participants(n=1419,48%)in China were younger,and more often male,hypertensive and with prior stroke and coronary artery disease,but less likely to have atrial fibrillation and use antihypertensive,antithrombotic and lipid-lowering agents,compared with non-China patients with *** China participants had more AIS due to large artery occlusion,were treated later and had differing ancillary management,there was no significant difference in 90-day modified Rankin scale scores 2–6(55.6% vs 47.8%;OR,adjusted for baseline and management factors 0.87(95%CI 0.71 to 1.07;p=0.20))and risk of sICH(Safe Implementation of Thrombolysis in Stroke-Monitoring Study criteria:1.4% vs 1.8%;p=0.12)compared with non-China *** was no heterogeneity in the treatment effects of low-dose versus standard-dose alteplase between China and non-China *** Patients with AIS recruited to the ENCHANTED trial in China had similar outcomes in response to thrombolysis treatment despite significantly differing demographic,clinical and management factors to patients with AIS in other regions.

关键词： hypertensive doses younger

Spontaneous passage of common bile duct stones in jaundiced patients

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 209-213页

作者： Valentina Lefemine richard john Morgan Department of General Surgery Glan Clwyd Hospital

BACKGROUND:Common bile duct(CBD)stones are known to pass spontaneously in a significant number of patients. This study investigated the rate of spontaneous CBD stones passage in a series of patients presenting with jaundice due to *** patients were managed surgically,allowing CBD intervention to be avoided in the event of spontaneous passage of CBD stones. METHOD:Retrospective analysis of patients presenting with jaundice due to CBD stones,and managed surgically with laparoscopic cholecystectomy and intra-operative cholangiogram with or without CBD exploration. RESULTS:The jaundice settled pre-operatively in 76/108 patients, and in 60/108 the CBD stones had passed spontaneously by the time of *** 60 patients avoided any intervention to their CBD. CONCLUSIONS:CBD stones pass spontaneously in more than half of jaundiced *** management(laparoscopic cholecystectomy and intra-operative cholangiogram,with willingness to perform CBD exploration if positive)allows the avoidance of CBD intervention in these patients.

关键词： cholecystectomy cholangiogram common bile duct stones

How generalists coexist: the role of floral phenotype and spatial factors in the pollination systems of two Ranunculus species

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Journal of Plant Ecology 2014年第5期7卷 480-489页

作者： richard P.Kipling john Warren Institute of Biological Environmental and Rural Science Aberystwyth UniversityPenglais CampusAberystwythCeredigionSY233FGUK

Aims Competition for pollinators between phenotypically similar flowers is believed to play an important role in floral trait diversification in the ***,in many plant communities,species with apparently similar floral phenotypes and generalist pollina-tion systems ***,the pollination systems of Ranunculus acris *** Ranunculus repens *** investigated to determine the factors enabling the species to coexist within apparently over-lapping pollination *** Sympatrically flowering populations of *** and *** were investigated at three study sites in West *** flo-ral phenotypes of the two species were compared using meas-urements of floral morphology and spectral analyses of petal reflectance,using principal component analysis and bee and fly colour-space *** of inter-specific discrimina-tion by foraging insects was tested for in the field and using floral *** relative roles of behavioural constancy and spatial patchiness in maintaining pollinator fidelity were *** Findings The floral phenotypes of *** and *** differed *** bees were highly constant when foraging at flowers of the two species and patchy floral distribution explained some of the observed *** visiting mixed floral arrays appeared to discriminate between the species,visiting more *** than *** flowers,but there was no difference in the number of vis-its to single-species *** bees were more likely to display constancy to flowers of *** in the *** in floral distribution,subtle differences in floral phenotype,pollinator preferences and behavioural constancy are all likely to con-tribute to the continued coexistence of *** and ***,despite apparent overlap in their pollination *** differences have the potential to facilitate the maintenance of species diversity in plant com-munities,even where plants appear to share similar floral p

关键词： floral phenotype pollination niche Ranunculus functional specialization constancy

Pursuit of the Modern While Preserving Tradition： The Japan Poems of Huang Zunxian

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2018年第2期12卷 182-216页

作者： richard john Lynn Department of East Asian Studies University of Toronto Ontario M5S 3H1 Canada

Huang Zunxian, member of the staff of the Qing legation in Tokyo （1877-82）, became acquainted with prominent Japanese literati （bunjin）. His experiences provide a window of information and insight into the cultural atmosphere of early Meiji Japan and the attitude of progressive and Chinese intellectuals then resident there. With the skills of a literatus, Huang had access to the modes of discourse and thought of his hosts, so formed discriminating views of almost all aspects of Japanese life in an era of change. His experience is captured in some 200 quatrains in the two editions of his Riben zashi shi （Poems on miscellaneous subjects from Japan, 1879 and 189o）, whose contents overlap to include different poems and different versions of same poems. The poems were intended to have more than literary impact--to enlighten those in power in China by casting Japan in a positive light and promote Japan as a model for reform and modernization. Huang linked Japanese tradition with the Chinese, which he did in poems emphasizing their common high culture. The scope of the poems is quite broad： Japanese history and geography, Sino-Japanese cultural relations, Chinese culture in Japan, poetry （kanshi） and prose （kanbun）, painting and calligraphy, Confucianism and Buddhism, the Meiji Restoration and modernization, new political and social institutions, the Diet, local government, political parties, museums, taxation, education reform, women＇s education. Many subjects were unknown to earlier tradition but now topical and urgent as China began to shed old ways and embrace the new.

关键词： Huang Zunxian Meiji Restoration first qing legation to Tokyo,Riben zashi shi Sino-Japanese cultural relations

Smoking influences outcome in patients who had thrombolysed ischaemic stroke:the ENCHANTED study

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Stroke & Vascular Neurology 2021年第3期6卷 395-401,I0033,I0034页

作者： Lingli Sun Lili Song Jie Yang richard I Lindley thompson Robinson Pablo M Lavados Candice Delcourt Hisatomi Arima Bruce Ovbiagele john Chalmers Craig S Anderson Xia Wang The George Institute for Global Health Peking University Health Science CentreBeijingChina The George Institute for Global Health University of New South WalesSydneyNSWAustralia Department of Neurology The First Affiliated Hospital of Chengdu Medical CollegeChengduChina Faculty of Medicine University of SydneySydneyNSWAustralia Department of Cardiovascular Sciences and NIHR Biomedical Research Unit for Cardiovascular Sciences University of LeicesterLeicesterUK Clínica Alemana de Santiago Universidad del DesarrolloSantiago de ChileRegion Metropolitana de SChile Department of Preventive Medicine and Public Health Faculty of MedicineFukuoka UniversityFukuokaJapan San Francisco VA Healthcare System University of CaliforniaSan FranciscoCaliforniaUSA

Background and purpose As studies vary in defining the prognostic significance of smoking in acute ischaemic stroke(AIS),we aimed to determine the relation of smoking and key outcomes in patient participants who had thrombolysed AIS of the international quasi-factorial randomised Enhanced Control of Hypertension and Thrombolysis Stroke Study(ENCHANTED).Methods Post-hoc analyses of ENCHANTED,an international quasi-factorial randomised evaluation of intravenous alteplase-dose comparison and levels of blood pressure control in patients who had thrombolysed *** logistic regression models with inverse probability of treatment weighting(IPTW)propensity scores were used to determine associations of self-reported smoking status and clinical outcomes,according to 90-day modified Rankin Scale(mRS)scores and symptomatic intracerebral haemorrhage(sICH).Results Of 4540 patients who had an AIS,there were 1008(22.2%)current smokers who were younger and predominantly male,with more comorbidities of hypertension,coronary artery disease,atrial fibrillation and diabetes mellitus,and greater baseline neurological impairment,compared with *** univariate analysis,current smokers had a higher likelihood of a favourable shift in mRS scores(OR 0.88,95%CI 0.77 to 0.99;p=0.038)but this association reversed in a fully adjusted model with IPTW(adjusted OR 1.15,95%CI 1.04 to 1.28;p=0.009).A similar trend was also apparent for dichotomised poor outcome(mRS scores 2–6:OR 1.18,95%CI 1.05 to 1.33;p=0.007),but not with the risk of sICH across standard *** Smoking predicts poor functional recovery in patients who had thrombolysed *** registration number NCT01422616.

关键词： patients smoke acute

Vasectomy by epithelial curettage without suture or cautery： a pilot study in humans

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Asian Journal of Andrology 2010年第3期12卷 315-321,I0008页

作者： john K. Amory john W. Jessen Charles Muller richard E. Berger Department of Medicine Center for Research in Reproduction and Contraception University of Washington School of Medicine Seattle WA 98195 USA private Practice Dentistry Seattle WA 98195 USA Department of Urology University of Washington School of Medicine Seattle WA 98195 USA

Curettage of the epithelium of the vas deferens might be a safe and effective method of male sterilization. We conducted a pilot study of vasectomy by epithelial curettage with a novel microcurette called the Vas-X in 12 normal men requesting elective sterilization. Seminal fluid analysis was obtained monthly after the procedure for 6 months. Pain was assessed by questionnaire. Three months after the procedure, all men attained sperm concentrations of less than 0.2 million sperm per mL, and seven were azoospermic. Post-procedural pain was minimal. Nine men ultimately achieved and maintained azoospermia; however, 4 to 6 months after the procedure, sperm concentrations increased in three of the 12 subjects, necessitating repeat vasectomy. Microscopic examination of the vas deferens from these failures revealed re-canalization. Vasectomy by epithelial curettage can result in effective sterilization; however, 1/4 of the subjects were not effectively sterilized by the procedure due to re-canalization of the vas deferens. Epithelial curettage will require further refinement to determine if it is a viable form of vasectomy.

关键词： male contraception male sterilization re-canalization spermatogenesis vas deferens vasectomy failure