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Patterns of host use by a precocial obligate brood parasite, the Black-headed Duck: ecological and evolutionary considerations

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Chinese Birds 2013年第1期4卷 71-85,100页

作者： Bruce E.LYON john m.eadie 美国加州大学Santa Cruz分校生态与进化生物学系美国加州大学Davis分校野生动物与鱼类保护生物学系

The Black-headed Duck (Heteronetta atricapilla) is unique among obligate avian brood parasites because its highly precocial young leave the host nest shortly after hatching and impose no post-hatching costs on their hosts. Accordingly, we might expect host-parasite interactions in this parasite to differ strikingly from those of other brood parasites — they should be able to parasitize a broad diversity of hosts and be highly successful with these hosts. We conducted the second detailed study ever completed on patterns of host use in Black-headed Ducks. Based on four years of systematic searches of multiple marshes in Argentina, we found no evidence that Black-headed Ducks ever had nests of their own, confirming the previous conclusion that Black-headed Ducks are, indeed, true obligate brood parasites. Contrary to expectation, however, we found that Heteronetta is ecologically dependent on a surprisingly small number of host species — two species of coots and a gull — all of which are widespread and locally abundant species. Other species are numerically less important as hosts either because they are relatively uncommon, or because they are avoided by the ducks. In the three main host species, hatching success of the duck eggs was also surprisingly low (≤ 28%), based on expectations for a precocial parasite, mainly due to host rejection or neglect. mortality due to predation on host nests, in contrast, was low for all three primary host species. These observations corroborate Weller’s observations from a single-year study. The combination of a dependence on few primary hosts and a relatively low hatching success are inconsistent with some previous hypotheses for the evolution of obligate brood parasitism in Heteronetta. Instead, our observations, and those of Weller, suggest that intense nest predation in Austral wetlands, coupled with an abundance of a few common host species that aggressively defend their nests and obtain high nest success rates, may have been an

关键词： brood parasitism egg rejection Fulica Heteronetta atricapilla host use nest success precocial bird Red-gartered Coot Red-fronted Coot waterfowl

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Human-tiger conflict:A review and call for comprehensive plans

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Integrative Zoology 2010年第4期5卷 300-312页

作者： john m.GOODRICH Wildlife Conservation Society BronxNew YorkNYUSA

Human-tiger(Panthera tigris Linnaeus,1758)conflicts(HTC),manifested primarily as attacks on people and domestic animals,exacerbate at least 2 major threats to tigers:(i)conflicts often result in mortality or removal of tigers from the wild;and(ii)they result in negative attitudes towards tigers by local people,thereby reducing support for tiger *** HTC has decreased over the past century,it will likely increase if current and proposed conservation initiatives to double tiger populations are *** HTC could undermine successful conservation initiatives if proactive steps are not taken to reduce *** present paper provides a review of the impacts of HTC and the measures taken to reduce it in ways that reduce negative impacts on both humans and tigers,and stresses the need for development and implementation of comprehensive plans to reduce HTC.

关键词： carnivore depredation human-tiger conflict Panthera tigris tiger

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Fusion of bone marrow-derived cells with cancer cells: metastasis as a secondary disease in cancer

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Chinese Journal of Cancer 2014年第3期33卷 133-139页

作者： john m.Pawelek Department of Dermatology and the Yale Cancer Center Yale University School of Medicine

This perspective article highlights the leukocyte-cancer cell hybrid theory as a mechanism for cancer metastasis. Beginning from the first proposal of the theory more than a century ago and continuing today with the first proof for this theory in a human cancer, the hybrid theory offers a unifying explanation for metastasis. In this scenario, leukocyte fusion with a cancer cell is a secondary disease superimposed upon the early tumor, giving birth to a new, malignant cell with a leukocyte-cancer cell hybrid epigenome.

关键词： Bone marrow-derived cell-cancer cell hybrids metastasis cell fusion

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Synthesis of LiSm_(0.01)mn_(1.99)O_4 by molten salt technique

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Journal of Rare Earths 2010年第2期28卷 255-259页

作者： m Helan L john Berchmans Department of Chemistry Jamal Mohamed College (Autonomous) Electropyrometallurgy Division Central Electrochemical Research Institute

Samarium substituted lithium manganese oxide powders were successfully prepared by molten-salt synthesis(mSS) using eutectic mixture of LiCl,SmCl3.6H2O and mnO2 salt at 700 °*** synthesis was carried out in open *** crystalline powders were characterized for their phase identification using X-ray diffraction(XRD) *** physico-chemical properties of the samarium substituted lithium manganese oxide powders were investigated by thermal analysis(TGA/DTA),FT-IR spectroscopy,EDAX,electron par...

关键词： LiSm0.01mn1.99O4 molten salt synthesis cathode materials rare earth ion

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Fuzzy modeling of Surficial Uranium Prospectivity in British Columbia(Canada)with a Weighted Fuzzy Algebraic Sum Operator

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Journal of Earth Science 2021年第2期32卷 293-309页

作者： Emmanuel john m.Carranza School of Agricultural Earth and Environmental SciencesUniversity of KwaZulu-NatalWestville CampusDurban 4041South Africa

This paper demonstrates knowledge-guided fuzzy logic modeling of regional-scale surficial uranium(U)prospectivity in British Columbia(Canada).The deposits/occurrences of surficial U in this region vary from those in Western Australia and Namibia;thus,requiring innovative and carefully-thought techniques of spatial evidence generation and *** novelty,this papers introduces a new weighted fuzzy algebraic sum operator to combine certain spatial evidence *** analysis trialed several layers of spatial evidence based on conceptual mineral system model of surficial U in British Columbia(Canada)as well as tested various models of evidence ***-linear weighted functions of(a)spatial closeness to U-enriched felsic igneous rocks was employed as U-source spatial evidence,(b)spatial closeness to paleochannels as fluid pathways spatial evidence,and(c)surface water U content as chemical trap spatial *** best models of prospectivity created by integrating the layers of spatial evidence for U-source,pathways and traps predicted at least 85%of the known surficial U deposits/occurrences in>10%of the study region with the highest prospectivity fuzzy *** results of analyses demonstrate that,employing the known deposits/occurrences of surficial U for scrutinizing the spatial evidence layers and the final models of prospectivity can pinpoint the most suitable critical processes and models of data integration to reduce bias in the analysis of mineral prospectivity.

关键词： fuzzy logic mineral systems surficial uranium fuzzy algebraic sum

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Sorption and phase distribution of ethanol and butanol blended gasoline vapours in the vadose zone after release

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Journal of Environmental Sciences 2014年第3期26卷 608-616页

作者： Ejikeme Ugwoha john m. Andresen Chemical and Environmental Engineering University of Nottingham School of Engineering and Physical Sciences Heriot-Watt University

The sorption and phase distribution of 20% ethanol and butanol blended gasoline （E20 and B20） vapours have been examined in soils with varying soil organic matter （SOm） and water contents via laboratory microcosm experiments. The presence of 20% alcohol reduced the sorption of gasoline compounds by soil as well as the mass distribution of the compounds to soil solids. This effect was greater for ethanol than butanol. Compared with the sorption coefficient （Kd） of unblended gasoline compounds, the Kd of E20 gasoline compounds decreased by 54% for pentane, 54% for methylcyclopentane （mCP） and 63% for benzene, while the Kd of B20 gasoline compounds decreased by 39% for pentane, 38% for mCP and 49% for benzene, The retardation factor （R） of E20 gasoline compounds decreased by 53% for pentane, 53% for mCP and 48% for benzene, while the R of B20 gasoline compounds decreased by 39% for pentane, 37% for mCP and 38% for benzene. For all SOm and water contents tested, the Kd and R of all gasoline compounds were in the order of unblended gasoline 〉 B20 〉 E20, indicating that the use of high ethanol volume in gasoline to combat climate change could put the groundwater at greater risk of contamination,

关键词： butanol-blended gasoline ethanol-blended gasoline phase distribution soil organic matter soil water content sorption vadose zone

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Host RNA circles and the origin of hepatitis delta virus

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World Journal of Gastroenterology 2014年第11期20卷 2971-2978页

作者： john m Taylor Fox Chase Cancer Center PhiladelphiaPA 19111United States

Recent reports show that many cellular RNAs are processed to form circular species that are relatively abundant and resistant to host *** some cases,such circles actually bind host *** depletion of available microRNAs appears to have biological roles;for instance,in homeostasis and *** findings regarding host RNA circles support a speculative reappraisal of the origin and mode of replication of hepatitis delta virus,hepatitis delta virus(HDV),an agent with a small circular RNA genome;specifically,it is proposed that in hepatocytes infected with hepatitis B virus(HBV),some viral RNA species are processed to circular forms,which by a series of chance events lead to an RNA that can be both replicated by host enzymes and assembled,using HBV envelope proteins,to form particles some of which are *** a model also may provide some new insights into the potential pathogenic potential of HDV *** return,new insights into HDV might provide information leading to a better understanding of the roles of the host RNA circles.

关键词： Hepatitis B virus Hepatitis delta virus Circular RNA Ribozymes microRNA

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The GPPS HI survey——A deeper view of the milky Way galaxy

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Science China(Physics,mechanics & Astronomy) 2022年第12期65卷 68-69页

作者： john m.Dickey School of Natural Sciences University of TasmaniaHobart Tas 7001Australia

The paper in this volume by Hong et al.[1]describing a new survey of the radio frequency spectral line of hydrogen,that astronomers call the HI line,shows some dramatic images of the milky Way *** Five-hundred-meter Aperture Spherical radio Telescope,FAST,has done this survey as part of the Galactic Plane Pulsar Snapshot(GPPS)Survey[2].

关键词： GPPS galaxy survey

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Virus entry mediated by hepatitis B virus envelope proteins

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World Journal of Gastroenterology 2013年第40期19卷 6730-6734页

作者： john m Taylor Fox Chase Cancer Center PhiladelphiaPA19111United States

Hepatitis B virus(HBV),a major cause of human liver disease worldwide,encodes three envelope proteins needed for the attachment and entry of the virus into susceptible host cells.A second virus,hepatitis delta virus,which is known to enhance liver disease in HBV infected patients,diverts the same HBV envelope proteins to achieve its own assembly and *** the lab,lentiviral vectors based on human immunodeficiency virus type 1 can be assembled using the HBV envelope proteins,and will similarly infect susceptible *** article provides a partial review and some personal reflections of how these three viruses infect and of how recipient cells become susceptible,along with some consideration of questions that remain to be answered.

关键词： Hepatitis B virus Hepatitis delta virus Receptor Envelope proteins Entry

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THE SULFIDATION/OXIDATION RESISTANCE OF TWO Ni-Cr-Al-Y ALLOYS AT 700℃

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Acta metallurgica Sinica(English Letters) 2004年第2期17卷 166-174页

作者： Y.X.Lu W.X.Chen R-eadie DepartmentofmaterialsEngineering UniversityofPetroleumDongying257061China DepartmentofChemicalandmaterialsEngineering UniversityofAlbertaEdmontonAlberta（T6G2G6）Canada

The high temperature corrosion resistance of Ni-25.9Cr-13.5Al-1.2Y-0.6Si and Ni-10.2Co-12.4Cr16.0Al-0.5Y-0.2Hf alloys was assessed in sulfidation/oxidation envi-ronments. In the environment with a sulfur partial pressure of 1Pa. and an oxygenpartial pressure of 10^(-19)Pa, both these alloys exhibited three distinct stages in theweight gain-time curve when tested at 700℃. In the initial stage, selective sulfidationof Cr suppressed the formation of the other metal sulfides, resulting in lower weightgains. In the transient stage, breakdown and cracking of Cr sulfides and insufficientconcentration of Cr at the outer zone led to the rapid formation of Ni sulfides anda rapid increase in weight. In the steady-state stage, corrosion was controlled by thediffusion of anions and/or cations, which led to a parabolic rate law.

关键词： sulfidation and oxidation corrosion resistance m-Cr-Al-Y type alloy

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