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Dur’ngoi Ophiolite in East Kunlun, northeast Tibetan Plateau: Evidence for Paleo-Tethyan Suture in northwest China

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Journal of China University of Geosciences 2009年第2期20卷 303-331页

作者：杨经绥史仁灯吴才来王希斌 paul T Robinson Key Laboratory for Continental Dynamics of the Ministry of Land and Resources Institute of GeologyChinese Academy of Geological Sciences Department of Earth Sciences Dalhousie University

The A＇nyemaqen （阿尼玛卿） ophiolite belt along the southern margin of the East Kunlun （昆仑） Mountains marks the suture formed by the closure of paleo-Tethys. The Dur＇ngoi ophiolite in the eastern part of this belt consists of meta-peridotite, mafic-ultramafic cumulates, sheeted dikes and basaltic lavas. The meta-peridotites consist of dunite, harzburgite, lherzolite, feldspar-bearing lherzolite and garnet-bearing lherzolite and contain residual spinel with Cr# [100×Cr/（Cr＋Al）] ranging from 30 to 57 and Mg# [100×Mg/（Mg＋Fe2＋）] ranging from 50 to 75, indicating an Al- and Mg-rich series. The meta-peridotites have a relatively narrow range of composition with Mg# of 89.2-92.6, Al2O3 contents of （1-4） wt.% and slightly depleted chondrite normalized REE patterns, indicating that they represent relict mantle material that has undergone intermediate to low degrees of partial melting. Garnets in the lherzolite are andradite, enriched in Ca and Fe and depleted in Mg and AI （And=95-97, Pyr=0.3-5, Gro=0-3）, indicating a metamorphic origin. The cumulate rocks mainly consist of dunite, wehrlite, pyroxenite and gabbro. A well-layered gabbro-pyroxenite complex is defined by modal variations in plagioclase and pyroxene. Blocks of garnet-pyroxenite or rodingite are locally present in the meta-peridotites. Garnets in the cumulate rocks are grossular （Gro=69-90, And=9-19, Br=l-12）, also metamorphic origin. The diabase dikes are moderately depleted in LREE [（La/Sm）n=0.5-0.8] and HREE resulting in slightly convex chondrite-normalized patterns with slightly positive Eu anomalies （δEu=1.1-1.3）. The basaltic lavas have REE patterns similar to those of MORB with （La/Sm）n ratios of 0.5-1 and small negative Eu anomalies. They appear to have been derived from a depleted mantle source and to have undergone little or no differentiation during crystallization. SHRIMP U-Pb dating of zircons from the basalts yields 286pb/238U ages of 276-319 Ma （average 308.0±4.9 Ma）. The Dur＇ngoi ophiolite is interprete

关键词： ophiolite Dur'ngoi A'nyemaqen East Kunlun Tibet.

Reuse of liver grafts following the brain death of the initial recipient

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World Journal of Hepatology 2014年第6期6卷 443-447页

作者： Hideaki Tanaka Vivian C McAlister Mark A Levstik Cameron n Ghent paul J Marotta Douglas Quan William J Wall Multi-Organ Transplant Program London Health Sciences CentreLondonOntario N6A 5A5Canada Department of Pediatric Surgery Faculty of MedicineUniversity of TsukubaTsukuba CityIbaraki 305-8575Japan Canadian Armed Forces Health Service OttawaOntario K1A 0K2Canada

AIM: To determine if there is a reasonable prospect of success of a re-use liver ***: We systematically searched for reports of liver graft re-use using electronic searches of PubMed and Web of Knowledge. We performed hand searches of references lists of articles reporting re-use of ***: A systematic review of the literature reveals 28 liver transplantations using previously transplanted grafts. First and second recipients ranged in age from 4 to 72 years and 29 to 62 years respectively. Liver disease in the first recipient was varied including 5(18%) patients with fulminant liver failure who died subsequently of cerebral edema. The second transplanta-tion was performed after a median interval of 5 d(one day-13 years). Viral hepatitis was present in 3(11%) of the initial recipients and in 8(29%) of final recipients. Hepatocellular carcinoma was present in 6(21%) of the final recipients. Early survival after the final transplantation was 93%, whereas long-term survival was 78% with a mean follow-up of 23.3(3-120) ***: Outcomes of transplantation using previously transplanted grafts in this select population are similar to those seen with conventional grafts.

关键词： Reuse Liver graft Brain death Liver transplantation

Analysis of a 1 kW organic Rankine cycle using a scroll expander for engine coolant and exhaust heat recovery

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Frontiers in Energy 2017年第4期11卷 527-534页

作者： Yiji LU Anthony paul ROSKILLY Long JIAnG Longfei CHEn Xiaoli YU Sir Joseph Swan Centre for Energy Research Newcastle University Newcastle NE1 7RU UK Institute of Refrigeration and Cryogenics Shanghai Jiao TongUniversity Shanghai 200240 China School of Energy and Power Engineering Beihang University Beijing 100191 China Department of Energy Engineering Zhejiang University Hangzhou310027 China

The development of engine waste heat recov- ery technologies attracts ever increasing interests due to the rising strict policy requirements and environmental con- cerns. This paper presented the study of engine coolant and exhaust heat recovery using organic Rankine cycle （ORC）. Eight working fluids were selected to evaluate and compare the performance of the integrated waste heat recovery system. Rather than the conventional engine ORC system mainly focusing on the utilization of exhaust energy, this work proposed to fully use the engine coolant energy by changing the designed parameters of the ORC system. The case study selected a small engine as the heat source to drive the ORC system using a scroll expander for power production. The evaluation results suggest that under the engine rated condition, the solution to fully recover the engine coolant energy can achieve a higher power generation performance than that of the conven- tional engine ORC system. The results suggest that adding a recuperator to the ORC system can potentially improve the system performance when the working fluids are dry and the overall dumped heat demand of the system can be reduced by 12% under optimal conditions. When the ORC evaporating and condensing temperature are respectivelyset at 85℃ and 30℃, the integrated engine waste heat recovery system can improve the overall system efficiency by 9.3% with R600, R600a or n-Pentane as the working fluid.

关键词： organic Rankine cycle scroll expander cool-ant and exhaust recovery internal combustion engine

Impact of a national basic skills in colonoscopy course on trainee performance: An interrupted time series analysis

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World Journal of Gastroenterology 2020年第23期26卷 3283-3292页

作者： Keith Siau James Hodson John T Anderson Roland Valori Geoff Smith paul Hagan Marietta Iacucci paul Dunckley Joint Advisory Group on Gastrointestinal Endoscopy Royal College of PhysiciansLondon NW14LEUnited Kingdom nIHR Biomedical Research Centre University of BirminghamBirmingham B152TTUnited Kingdom Institute of Translational Medicine University Hospitals BirminghamBirmingham B152TTUnited Kingdom Department of Gastroenterology Gloucestershire Hospitals NHSFTCheltenham GL537ANUnited Kingdom Department of Gastroenterology Imperial College NHS Foundation TrustLondon NW14LEUnited Kingdom Endoscopy Department Derby Royal HospitalDerby GL13NNUnited Kingdom

BACKGROUnD The Joint Advisory Group on Gastrointestinal Endoscopy basic skills in colonoscopy(BSC) course was introduced in 2009 to improve colonoscopy training within the United Kingdom, but its impact on trainee performance is *** To assess whether attendance of the BSC could improve colonoscopy *** Trainees awarded colonoscopy certification between 2011-2016 were stratified into 3 groups according to pre-course procedure count(nd > 140).Study outcomes, comprising the unassisted caecal intubation rate(CIR) and the performance indicator of colonic intubation(PICI), were studied over the 50 procedures pre and post-course. Interrupted time series analyses were performed to detect step-change changes attributable to the *** A total of 369 trainees with pre-course procedure counts of n = 118), 70-140(n = 121) and > 140(n = 130) were included. Over the 50 pre-course procedures,significant linear improvements in CIR were found, with average increases of 4.2,3.6 and 1.7 percentage points(pp) per 10 procedures performed in the nd > 140 groups respectively(all P nificant step-change improvement in CIR, increasing from 46% in the last pre-course procedure, to 51% in the first procedure post-course(P = 0.005). The CIR step-change was not significant in the 70-140(68% to 71%;P = 0.239) or > 140(86% to 87%;P = 0.354) groups. For PICI, significant step-change improvements were seen in all three groups, with average increases of 5.6 pp(P nd 3.9 pp(P = 0.014) *** Attendance of the BSC was associated with a significant step-change improvement in PICI, regardless of prior procedural experience. However, CIR data suggest that the optimal timing of course attendance appears to be at earlier stages of training(< 70 procedures).

关键词： Colonoscopy Training Course Competency development Skills Endoscopy

Early terrestrial and lunar anorthosites:Comparative geochemistry and evolutionary processes

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Geoscience Frontiers 2024年第6期15卷 348-366页

作者： paul Sotiriou Ali Polat Tim Kusky Brian F.Windley School of the Environment University of WindsorWindsorON N9B 3P4Canada GeoZentrum nordbayern Friedrich-Alexander-UniversitätErlangen 91054BayernGermany Center for Global Tectonics State Key Laboratory for Geological Processes and Mineral ResourcesChina University of GeosciencesWuhanHubei ProvincePR China School of Geography Geology and the EnvironmentUniversity of LeicesterLeicester LE17RHUK

In a paper in 1970,Brian Windley first recognised that early terrestrial and lunar anorthosites both have calcic plagioclase,and low TiO_(2)and high CaO and Al_(2)O_(3)*** these similarities,the geochemistry of early terrestrial and lunar anorthosites has not been rigorously compared and *** this end,we compiled 425 analyses from 212 early terrestrial anorthosite occurrences and 306 analyses from 16 lunar anorthosite *** was supplemented by a compilation of plagioclase anorthite(An)contents and pyroxene Mg#from early terrestrial and lunar *** terrestrial anorthosites have lower whole-rock An contents but similar Mg#to lunar *** CaO contents of lunar anorthosites are higher than those of early terrestrial anorthosites for a given MgO and Al_(2)O_(3)content,early terrestrial anorthosites have higher SiO_(2)contents than lunar anorthosites at a given MgO content,and lunar anorthosites have higher Eu/Eu*anomaly ratios yet broadly similar La/Yb and nd/Sm ratios than early terrestrial *** early terrestrial anorthosites have less fractionated chondrite-normalised rare earth element(REE)patterns and less prominent positive Eu anomalies than lunar *** anorthosites have higher plagioclase An contents,yet a similar range of pyroxene Mg#compared to their early terrestrial *** early terrestrial anorthosites are more fractionated than some lunar *** interpretations imply that most early terrestrial anorthosites crystallised from basaltic parental magmas that were generated by high-degree partial melting of sub-arc asthenosphere mantle wedge sources that were hydrated by slab-derived fluids,with the remainder being associated with mid-ocean ridge and mantle plume *** of the arc-related early terrestrial anorthosites were influenced by crustal *** addition,early terrestrial anorthosites originated from partial melting of the mantle at variou

关键词： Early terrestrial anorthosites Lunar anorthosites Geochemistry Mineral chemistry

When multi-functional landscape meets Critical Zone science:advancing multi-disciplinary research for sustainable human well-being

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national Science Review 2019年第2期6卷 349-358页

作者： Ying Luo Yihe Lü Bojie Fu paul Harris Lianhai Wu Alexis Comber State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Joint Center for Global Change Studies Rothamsted Research North Wyke School of Geography University of Leeds

Environmental degradation has become one of the major obstacles to sustainable development and human well-being internationally. Scientific efforts are being made to understand the mechanism of environmental degradation and sustainability. Critical Zone(CZ) science and research on the multi-functional landscape are emerging fields in Earth science that can contribute to such scientific efforts. This paper reviews the progress, similarities and current status of these two scientific research fields, and identifies a number of opportunities for their synergistic integration through functional and multi-functional approaches,process-based monitoring, mechanistic analyses and dynamic modeling, global long-term and networked monitoring and systematic modeling supported by scaling and deep coupling. These approaches proposed in this paper have the potential to support sustainable human well-being by strengthening a functional orientation that consolidates multi-functional landscape research and CZ science. This is a key challenge for sustainable development and human well-being in the twenty-first century.

关键词： multi-functional landscapes Critical Zone ecosystem services sustainable development human well-being

Unusual n-Alkane Distributions in Extracts from Marine Carbonate Rocks at High Levels of Maturity and Overmaturity

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Chinese Journal Of Geochemistry 2002年第4期21卷 322-333页

作者：李景贵 R.paul PHILP 崔明中 State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou 730000 China School of Geology and Geophysics University of Oklahoma Norman OK. 73019 U. S. A

n\|alkanes in extracts from possible carbonate source rocks of the Lower Ordovician Majiagou Formation in the central gas field of the Shanganning Basin and the Upper Sinian Dengying Formation in the Weiyuan gas field of the Sichuan Basin, are characterized by bimodal distributions with the dominant carbon numbers in the range C\- 17 \|C\- 21 and C\- 25 \|C\- 29 . In most samples, the lower carbon number components are present in greater abundance than the higher carbon number ones. Most samples contain significant concentrations of waxy hydrocarbons(C\- 22+ ) with C\- 21- /C\- 22+ ratios between 0.50 to 3.16, and an average value of 1.34. The n\|alkanes in extracts of outcrops and shallow core samples of Upper Proterozoic and Lower Palaeozoic carbonate rocks in the western and southern parts of the north China Basin are of unimodal distributions dominated by n\|alkanes maximizing in the C\- 25 \|C\- 29 range. These extracts have very high concentrations of waxy hydrocarbons with C\- 21- /C\- 22+ ratios all nging from 0 14 to 0 90 and averaging 0.36. All of the extracts have a marked odd/even predominance in the high molecular weight n\|alkane range regardless of whether they are from shallow or deep cores or outcrop samples. Simulation experiments were performed using typical sapropelic\|type kerogens from the immature Sinian Lower Xiamalin Formation carbonate\|rich shales collected at Jixian, Hebei Province, north China Basin, and the contemporary microplanktonic blue\|green algae Spirulina subsala. Results indicate that the unusual distribution of n\|alkanes in the extracts of Upper Proterozoic and Lower Palaeozoic carbonate rocks possibly originated from algae in the source rocks at high levels of maturity and overmaturity.

关键词：海藻中国海相碳酸盐岩链烷双峰分面成熟期

Effects of Imperfect Quality and Defective Items on Economic Production Lot Size

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厦门大学学报（自然科学版） 2002年第S1期41卷 247-页

作者： Raafat n Ibrahim paul Lochert Department of Mechanical Engineering Monash UniversityDepartment of Mechanical Engineering Monash University AustraliaAustralia

The classical EPQ model has been used for a long ti me and is widely accepted and implemented. nevertheless, the analysis for finding an economic lot size has based on a number of unrealistic assumptions. A common unrealistic assumption in using EPQ is that all units produced are of good quali ty. The classical EPQ model shows that the optimal lot size will generate minimum ma nufacturing cost, thus producing minimum setup cost and inventory cost. However, this is only true if all products manufactured in the process are assumed to be of good quality (i.e. all products are within the specification limits). In rea lity this is not the case, therefore, it is necessary to consider the cost of im perfect quality items, because this cost can influence the economic lot size. Ma ny studies and recent papers have indicated that there is a significant relation ship between economic production lot size and process/product quality. However, their models included either the imperfect quality items (not necessarily de fective) which are to be sold at a discounted price or defective items which can be reworked or rejected. The aim of this paper is to provide a framework to integrate three different sit uations (discounted pricing/rework/reject) into a single model. 100% inspection is performed in order to distinguish the amount of good quality items, imper fect quality items and defective items in each lot. In this paper, a mathematica l model is developed, and a numerical example is presented to illustrate the sol ution procedures. It is found that the economic production lot size tends to inc rease as the average percentage of imperfect quality items and defectives (rejec ted items) increases.

关键词： EPQ lot size imperfect/defective items

Evaluation of age, weaning weight, body condition score, and reproductive tract score in pre-selected beef heifers relative to reproductive potential

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Journal of Animal Science and Biotechnology 2019年第2期10卷 307-313页

作者： Sarah E.Dickinson Michelle F.Elmore Lisa Kriese-AnDerson Joshua B.Elmore Bailey n.Walker paul W.Dyce Soren P.Rodning Fernando H.Biase 1Department of Animal Sciences Auburn University559 Devall DrAuburnAL 36839USA.2Alabama Cooperative Extension SystemAuburnALUSA.

Background: Artificial insemination is a preferred breeding method for beef heifers as it advances the genetic background, produces a predictive and profitable calving season, and extends the heifer’s reproductive life *** reproductive efficiency in heifers is key for the success of beef cattle production systems, following artificial insemination, heifers are exposed to a bull for the remainder of the breeding season. Altogether, up to 95% of heifers might become pregnant in their first breeding season. Heifers that do not become pregnant at the end of the breeding season represent an irreparable economical loss. Additionally, heifers conceiving late in the breeding season to natural service, although acceptable, poses serious losses to producers. To minimize losses due to reproductive failure, different phenotypic parameters can be assessed and utilized as selection tools. Here, we tested the hypothesis that in a group of pre-selected heifers, records of weaning weight, age at weaning, age at artificial insemination, and age of dam differ among heifers of varied reproductive outcomes during the first breeding ***: none of the parameters tested presented predictive ability to discriminate the heifers based on the response variable(‘pregnant to artificial insemination’, ‘pregnant to natural service’, ‘not pregnant’). Heifers categorized with body condition score = 6 and reproductive tract score ≥ 4 had the greatest proportion of pregnancy to artificial insemination(49% and 44%, respectively). Furthermore, it was notable that heifers presenting body condition score = 6 and reproductive tract score = 5 presented the greatest pregnancy rate at end of the breeding season(89%). Heifers younger than 368 d at the start of the breeding season did not become pregnant to artificial insemination. Those young heifers had 12.5% chance to become pregnant in their first breeding season,compared to 87.5% if the heifers were older than 368 ***: Our results

关键词： Fertility Phenotypic selection Pregnancy outcome Replacement heifer