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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

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

A History of Fischer-Tropsch Wax Upgrading at Bp-from Catalyst Screening Studies to Full Scale Demonstration in Alaska

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Journal of Natural gas Chemistry 2006年第1期15卷 1-10页

作者： john p. Collins Joep J. H. m. Font Freide Barry Nay Bp Exploration America Inc. Bp Exploration Operating Company

Conversion of Fischer-Tropsch wax into high quality synthetic crude or finished transportation fuels such as premium diesel has been studied over the past 15 years within Bp. Catalyst screening and selection was carried out in dedicated micro-reactors and pilot plants, whose designs are critical to the performance selection. Variation in catalyst composition and defining the gas to oil feed ratios with the operating temperature are a few of the parameters studied. product selection and maximizing diesel yield combined with stability （catalyst life） were the ultimate drivers. The selected catalyst was then tested under commercial conditions in a dedicated 300 barrel per day demonstration plant. The products were also tested in engines to assess their combustion characteristics.

关键词： Fischer-Tropsch wax upgrading hydrocracking synthetic crude diesel naphtha engine emission

Establishing proof of concept:platelet-rich plasma and bone marrow aspirate concentrate may improve cartilage repair following surgical treatment for osteochondral lesions of the talus

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World Journal of Orthopedics 2012年第7期3卷 101-108页

作者： Niall A Smyth Christopher D murawski Amgad m Haleem Charles p Hannon Ian Savage-Elliott john g Kennedy Department of Orthopaedic Surgery Hospital for Special SurgeryNew YorkNY 10021United States

Osteochondral lesions of the talus are common injuries in the athletic patient. They present a challenging clinical problem as cartilage has a poor potential for healing. Current surgical treatments consist of reparative(microfracture) or replacement(autologous osteochondral graft) strategies and demonstrate good clinical outcomes at the short and medium term follow-up. Radiological findings and second-look arthroscopy however, indicate possible poor cartilage repair with evidence of fibrous infill and fissuring of the regenerative tissue following microfracture. Longer-term follow-up echoes these findings as it demonstrates a decline in clinical outcome. The nature of the cartilage repair that occurs for an osteochondral graft to become integrated with the native surround tissue is also of concern. Studies have shown evidence of poor cartilage integration,with chondrocyte death at the periphery of the graft, possibly causing cyst formation due to synovial fluid ingress. Biological adjuncts, in the form of platelet-rich plasma(pRp) and bone marrow aspirate concentrate(BmAC), have been investigated with regard to their potential in improving cartilage repair in both in vitro and in vitro settings. The in vitro literature indicates that these biological adjuncts may increase chondrocyte proliferation as well as synthetic capability, while limiting the catabolic effects of an inflammatory joint environment. These findings have been extrapolated to in vitro animal models, with results showing that both pRp and BmAC improve cartilage repair. The basic science literature therefore establishes the proof of concept that biological adjuncts may improve cartilage repair when used in conjunction with reparative and replacement treatment strategies for osteochondral lesions of the talus.

关键词： Osteochondral lesion Cartilage repair platelet-rich plasma Bone marrow aspirate concentrate

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

Investigating low dispersion isotope dissolution Lu-Hf garnet dates via in situ Lu-Hf geochronology,Kanchenjunga Himal

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geoscience Frontiers 2024年第3期15卷 137-145页

作者： Kyle p.Larson john m.Cottle mark Button Brendan Dyck Iva Lihter Sudip Shrestha Department of Earth Environmental and Geographic SciencesUniversity of British ColumbiaOkanaganKelownaCanada Department of Earth Science University of CaliforniaSanta BarbaraUSA Fipke Laboratory for Trace Element Research University of British ColumbiaOkanaganKelownaCanada

Re-examination of three specimens from the Kanchenjunga Himal of Nepal via in situ Lu-Hf garnet geochronology yields evidence of multiple garnet growth *** analyses from grain cores in two specimens define paleozoic regressions whereas analyses from grain rims in the same specimens define low-precision regressions consistent with the timing of Himalayan *** dates contrast with previously published low dispersion,ca.290 ma isotope dissolution(ID)Lu-Hf garnet dates for the same *** of Lu and spot age distribution in representative grains from the specimens examined yields calculated dates that approximate the permian-age regressions through the original ID *** findings demonstrate that it is possible to generate low dispersion ID Lu-Hf data from multigenerational garnet with significantly different-age growth events when approximately equal proportions of the different age reservoirs are included in multi-component aliquots.

关键词： Lu-Hf geochronology In situ Lu-Hf geochronology Kanchenjunga Himal

Functional dyspepsia:The role of visceral hypersensitivity in its pathogenesis

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World Journal of gastroenterology 2006年第17期12卷 2672-2676页

作者： john Keohane Eamonn m m Quigley Alimentary pharmabiotic Centre University College Cork CorkIreland

Functional, or non-ulcer, dyspepsia （FD） is one of the most common reasons for referral to gastroenterologists. It is associated with significant morbidity and impaired quality of life. many authorities believe that functional dyspepsia and irritable bowel syndrome represent part of the spectrum of the same disease process. The pathophysiology of FD remains unclear but several theories have been proposed including visceral hypersensitivity, gastric motor dysfunction, Helicobacter pylori infection and psychosocial factors. In this review, we look at the evidence, to date, for the role of visceral hypersensitivity in the aetiology of FD.

关键词： Visceral hypersensitivity motor dysfunction Helicobacter pylori psychosocial

Chaotic oscillations in a piecewise linear spring-mass system

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Theoretical & Applied mechanics Letters 2012年第5期2卷 49-52页

作者： manu p.john V.m.Nandakumaran International School of photonics Cochin University of Science and Technology

Chaotic oscillations are useful in assessing the health of a structure. Hence, simple chaotic systems which can easily be realized mechanically or electro-mechanically are highly desired. We study a new pieeewise linear spring-tnass system. The chaotic behaviour in this system is characterized using bifurcation diagrams and the invariant parameters of the dynamics. We also show that there exists a stochastic analogue of this system, which mimics the dynamical features of its deterministic counterpart. This allows a greater flexibility in practical designs as the chaotic oscillations are obtained either deterministically or stochastically. Also, the oscillations are low dimensional, which reduces the computational resources needed for obtaining the invariant parameters of this system.

关键词： chaotic oscillations piecewise linear system spring-mass system

geochemistry of core sediments from the southeastern Bay of Bengal:Inferences on weathering and early diagenetic changes

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geoscience Frontiers 2021年第2期12卷 495-504页

作者： A.prajith Abhishek Tyagi p.john Kurian National Centre for polar and Ocean Research(NCpOR) Ministry of Earth Sciences(MoES)Headland SadaVasco-da-Gama403804GoaIndia

A sediment core(ABp24/05),collected at a water depth of 3520 m from the southeastern Bay of Bengal was studied to determine the change in chemical weathering during the last glacial to deglacial periods and the factors of sedimentary environment which controlled earliest diagenetic changes in the sediment after its *** ratios of K/Rb,Ti/Al and Zr/Rb during~45 to~18 cal kyr *** the core sediments may be attributed to the stronger physical erosion and turbidity currents activity during this *** might have brought a higher quantity of unaltered minerals to the study *** ratios of K/Rb,Zr/Rb,and Ti/Al and increase of SiO_(2)/TiO_(2),Rb/Al and Cs/Al from~18 cal kyr *** present may be indicating an increase in the rate of chemical weathering during this *** time of increased chemical weathering in the study area is consistent with deglaciation warming in the tropical Indian Ocean and strengthening of river runoff into the Andaman *** change during the interglacial period by increased solar insolation thereby strengthened the summer monsoon which might have led to intensified chemical weathering in the source region since~18 cal kyr *** low organic carbon(OC),high mn/Al,Fe/Al and the mn-oxides minerals precipitation indicate prevailing of oxic conditions during~11 cal kyr *** the core sediments,which is contradictory to suboxic conditions developed in the deep ocean sediments in the western Bay of Bengal and the equatorial Indian *** low terrigenous influx and export of less OC to the bottom sediments might have created a favorable condition for the formation of mn-oxides in the study area during Holocene.

关键词： Bay of Bengal Trace elements Chemical weathering Summer monsoon mn-oxides