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THE JEHOL BIOTA （LOWER CRETACEOUS, CHINA）: NEW DISCOVERIES AND FUTURE PROSPECTS

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THE JEHOL BIOTA （LOWER CRETACEOUS, CHINA）: NEW DISCOVERIES...

Behavioural and energetic consequences of competition among three overwintering swan(Cygnus spp.)species

第十九届国际动物学大会

作者： Paul m.Barrett jason m.hilton Department of Palaeontology The Natural History Museum Cromwell Road London SW7 5BD UK School of Geography Earth and Environmental Sciences University of Birmingham UK

＜正＞Continuing work on the paleontology and sedimentology of the Jehol Group （Lower Cretaceous, China） is yielding numerous new insights into the evolution of many mesozoic plant and animal clades. Nevertheless, many questions remain unanswered regarding Jehol paleoenvironments, paleobiology and paleobiogeography. All of this information will be crucial in providing a detailed reconstruction of this extinct ecosystem.

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Avian Research 2021年第4期12卷 707-721页

作者： Kevin A.Wood Julia L.Newth Geoff m.hilton Eileen C.Rees Wildfowl&Wetlands Trust SlimbridgeGloucestershire GL27BTUnited Kingdom Centre for Ecology and Conservation/Environment and Sustainabil-ity Institute College of Life and Environmental SciencesUniversity of ExeterExeter TR109EZUnited Kingdom Department of Zoology University of CambridgeDowning StreetCambridge CB23EJUnited Kingdom

Background:Winter numbers of the northwest European population of Bewick's Swans(Cygnus columbianus bewickii)declined recently by c.40%.During the same period,numbers of two sympatric and ecologically-similar congeners,the mute Swan(Cygnus olor)and Whooper Swan(Cygnus cygnus)showed increases or *** has been suggested that these opposing population trends could have a causal relationship,as mute and Whooper Swans are larger and competitively dominant to Bewick's Swans in foraging *** so,effects of competition of mute and Whooper Swans on Bewick's Swans should be detectable as measurable impacts on behaviour and ***:Here,we studied the diurnal behaviour and energetics of 1083 focal adults and first-winter juveniles("cygnets")of the three swan species on their winter grounds in eastern *** analysed video recordings to derive time-activity budgets and these,together with estimates of energy gain and expenditure,were analysed to determine whether individual Bewick's Swans altered the time spent on key behaviours when sharing feeding habitat with other swan species,and any consequences for their energy expenditure and net energy ***:All three swan species spent a small proportion of their total time(0.011)on aggressive interactions,and these were predominantly intraspecific(≥0.714).mixed-effects models indicated that sharing feeding habitat with higher densities of mute and Whooper Swans increased the likelihood of engaging in aggression for cygnet Bewick's Swans,but not for *** levels of interspecific competition decreased the time spent by Bewick's Swan cygnets on foraging,whilst adults showed the opposite *** among low densities of conspecifics(m^(2)),individual Bewick's Swans spent more time on vigilance in the presence of higher densities of mute and Whooper Swans,whilst individuals within higher density Bewick's Swan flocks showed the opposite ***,we found no evide

关键词： Avian behaviour Energy expenditure Ethology Interference competition Interspecific interactions Time activity budgets Video observations

Endemic fossil seed plants from China and a reassessment of coniferophyte phylogeny

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Progress in Natural Science:materials International 1999年第10期9卷 48-55页

作者： jason hilton,王士俊,陈之端,田宝霖 Department of Palaeobotany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Department of Palaeobotany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Laboratory of Systematics and Evolution Institute of Botany Chinese Academy of Sciences Beijing 100093 China China University of mining and Technology ( Beijing) Beijing 100083 China

Recent palaeobotanical studies have provided new and important evidence on Chinese fossil plants. The majority of these fossils are distinct from fossil floras known from other geographical regions. However, remarkably few of these fossil plants have been successfully incorporated into cladistic analyses, to assess their importance on evolutionary relationships among major plant groups. For the first time our investigation incorporates three endemic Chinese fossil plant species into a cladistic analysis of the seed plants. These plants have been documented and reconstructed in detailed investigations of Palaeozoic coal balls from the Taiyuan Formation and are named Shanxioxylon sinensis , Shanx-ioxylon taiyuanensis and Pennsylvanioxylon tianii respectively. Previous investigations indicate that these plants belong to the now extinct Cordaitalean seed plants although they share many features with certain fossil conifers. As such, they are likely to be of significance to the ongoing and currently unresolv

关键词： phytogeny evolution coniferophyte Coniferales Cordaitales

Depositional model for Peat Swamp and Coal Facies Evolution Using Sedimentology, Coal macerals, Geochemistry and Sequence Stratigraphy

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Journal of Earth Science 2017年第6期28卷 1163-1177页

作者： Jing Lu Longyi Shao minfang Yang Kai Zhou James R.Wheeley Hao Wang jason hilton State Key Laboratory of Coal Resources and Safety mining China University of Mining and Technology School of Geography Earth and Environmental Sciences the University of Birmingham Langfang Branch of Petroleum Exploration and Development Research Insitute Petro China

As one of the most important source rocks and reservoirs of unconventional natural gas, the sedimentary environment and mode of peat swamp（the predecessor of coal seam） is important to the coal seam＇s spatial distribution, material composition, hydrocarbon generation potential, reservoir physical properties, etc. To reveal the depositional characteristics and history of environmental change in a terrestrial basin during a period of peat accumulation, the middle Jurassic aged #7 coal from Gaoquan in the Qaidam Basin（NW China） was investigated using sedimentology, maceral composition, geochemistry and sequence stratigraphy. Based on identification of the sedimentary shoreline break belt, wave energy depletion point and position of wave base, the peat swamp system can be subdivided into（1） lakeside plain,（2） low energy lakeshore,（3） high energy lakeshore, and（4） shallow lake subfacies. A new method for determining coal facies is proposed based on the combination of environmental parameters including oxidation-reduction levels, energy conditions and the influence of terrigneous sediments. The evolution of the coal seam shows that peat was deposited mainly in the low energy lakeshore and lakeside plain subfacies. Five types of sequence stratigrpahic surface and two types of parasequence were identified. Forced lake regressions and normal lake regressions are attributed as the causes of sequence boundaries. The sequence stratigraphic framework comprises six sequences and corresponding system tracts, and the curve of base-level for each demonstrates a characteristic initial period of slow rising followed by fast rising and then returning to slow rising. A model indicating the relationship among base-level changes, coal facies evolution, and the environmental features in the swamp is proposed that shows the environmental features of the swamp were controlled by both base-level changes and coal facies. Accompanying depositional environment changes from a lakeside plain to la

关键词： peat swamp sedimentary model coal facies base level coal maceral

Adaptively Controlled Hybrid Welding Using a High Brightness Laser

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稀有金属材料与工程 2011年第S4期40卷 1-5页

作者： C.m.Allen P.A.hilton TWI Ltd Granta ParkGreat AbingtonCambridgeCB21 6ALUnited Kingdom

Hybrid laser-mAG welding with real-time adaptive control has been *** welding conditions have been developed to produce ISO 13919-1 class B (stringent) quality butt welds between 8mm thickness steel plates,using a 5kW *** Yb fibre laser combined with conventional arc welding equipment.A laser vision seam tracking system has enabled a 7-axis robot,manipulating the hybrid welding head,to track butt joints in real time during *** laser vision system has also provided information on the variations in joint fit-up,in particular the width of any gaps,or height of any mismatches *** information has then been used to automatically adjust the robot position or speed,or arc welding parameters,depending on the fit-up *** this way,the tolerance of the hybrid process has been augmented,producing stringent quality welds over a wider range of joint fit-up cases than when using fixed conditions alone.

关键词： hybrid welding steel adaptive control fit-up tolerance

Continental chemical weathering during the Early Cretaceous Oceanic Anoxic Event(OAE1b): a case study from the Fuxin fluvio-lacustrine basin, Liaoning Province,NE China

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Journal of Palaeogeography 2020年第2期9卷 246-266页

作者： Xiao-Tao Xu Long-Yi Shao Bo Lan Shuai Wang jason hilton Jian-Yi Qin Hai-Hai Hou Jie Zhao College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China Shandong Key Laboratory of Depositional mineralization&Sedimentary mineral Shandong University of Science and TechnologyQingdao 266590China Northeast China Coalfield Geology Bureau 107 Exploration Team Fuxin 123000China School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK College of mining Liaoning Technical UniversityFuxin 123000China.

This study focuses on Early Cretaceous mudstones from the Shahai and Fuxin formations in the Fuxin continental basin. We analyse chemical weathering, land surface temperatures and palaeoclimates based on chemical weathering indices, and emphasize the implications of continental chemical weathering on nutrient fluxes into lakes and *** to Cr and Ni abundance, Al2O3-TiO2, La/Sc-Th/Co and V-Ni-Th×10 plots, as well as rare earth element(REE)analysis, mudstone samples from the Shahai and Fuxin formations were derived from the same type of provenance comprising mainly felsic igneous rocks. Chemical weathering trends reflected by the Chemical Index of Alteration(CIA),Weathering Index of Parker(WIP) and the mafic Index of Alteration for Oxidative weathering environments(mIA(O)) are consistent with each other and allow the geological succession to be divided into four stages. Land surface temperatures of the Shahai and Fuxin formations are estimated based on the linear relationship of CIA to temperature,and also can be divided into four stages consistent with those determined from chemical weathering trends. During Stage A(early part of the late Aptian) chemical weathering and land surface temperatures were relatively low and showed characteristic high fluctuations, while Stage B(latest Aptian) represented a transitional period where weathering rates and temperatures increased, and high amplitude fluctuations continued. Conditions changed markedly in Stage C(early Albian) with very high and stable weathering, and warm, humid climates, while in Stage D(middle and late Albian) conditions returned to low chemical weathering and land surface temperatures. These stages of chemical weathering and land surface temperature fluctuations represent responses to global climate fluctuations during the Early Cretaceous, with the early Albian high weathering intensities and warm, humid climates combining to create high nutrient levels that would have flushed through rivers int

关键词： Chemical weathering indices Land surface temperature mudstone Greenhouse conditions Ocean Anoxic Event 1 b Black shales

Prostate-specific antigen （PSA） screening： has the pendulum swung too far？

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Asian Journal of Andrology 2011年第5期13卷 655-656页

作者： jason m Phillips E David Crawford Department of Urology University of Colorado HealthSciences Center Aurora CO 80045 USA

Prostate-specific antigen （PSA） along with digital rectal exam has been the standard for prostate cancer screening in the United States for the past 20 years.1 During this time period, the improved detection of prostate cancer decreased related mortality more than 30%.2 In fact, metastases and their comorbidities have decreased more than 75% since the early 1990s, resulting in a higher incidence of early organ-confined disease. While it is clear that prostate cancer mortality statistics have improved, it is unclear whether men are overscreened.

关键词： overscreened Prostate-specific

The human gut sterolbiome:bile acid-microbiome endocrine aspects and therapeutics

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Acta Pharmaceutica Sinica B 2015年第2期5卷 99-105页

作者： jason m.Ridlon Jasmohan S.Bajaj Department of microbiology and Immunology Virginia Commonwealth University mcGuire VA medical Center Division of Gastroenterology Hepatology and Nutrition Virginia Commonwealth University

The human body is now viewed as a complex ecosystem that on a cellular and gene level is mainly prokaryotic. The mammalian liver synthesizes and secretes hydrophilic primary bile acids, some of which enter the colon during the enterohepatic circulation, and are converted into numerous hydrophobic metabolites which are capable of entering the portal circulation, returned to the liver, and in humans,accumulating in the biliary pool. Bile acids are hormones that regulate their own synthesis, transport, in addition to glucose and lipid homeostasis, and energy balance. The gut microbial community through their capacity to produce bile acid metabolites distinct from the liver can be thought of as an "endocrine organ"with potential to alter host physiology, perhaps to their own favor. We propose the term "sterolbiome" to describe the genetic potential of the gut microbiome to produce endocrine molecules from endogenous and exogenous steroids in the mammalian gut. The affinity of secondary bile acid metabolites to host nuclear receptors is described, the potential of secondary bile acids to promote tumors, and the potential of bile acids to serve as therapeutic agents are discussed.

关键词： Sterolbiome Gut microbiome Bile acids metabolite Therapeutic agent

Surgical solutions to the problem of massive weight loss

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World Journal of Gastroenterology 2006年第41期12卷 6602-6607页

作者： jason A Spector Steven m Levine Nolan S Karp Division of Plastic Surgery Weill medicine College of Cornell University New YorkNY 10021United States Institute of Reconstructive and Plastic Surgery Division of Plastic SurgeryNew York University School of MedicineNew YorkNY 10016United States

In response to the global rise in obesity, bariatric surgery has become increasingly more popular and successful As a result, the demand for body contouring following massive weight loss is rapidly growing. Although bariatric procedures may produce impressive weight loss, people who achieve massive weight loss are often unhappy with the hanging folds of skin and subcutaneous tissue that remain. This review examines the nature of the post-bariatric deformity in each body region and briefly reviews common approaches to their treatment.

关键词： Weight loss Bariatric surgery Body contour surgery