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Oxidative stress in alcohol-related liver disease

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World Journal of Hepatology 2020年第7期12卷 332-349页

作者： Huey K Tan euan yates Kristen Lilly Ashwin D Dhanda Hepatology Research Group Institute of Translational and Stratified MedicineFaculty of HealthUniversity of PlymouthPlymouth PL68BUUnited Kingdom South West Liver Unit University Hospitals Plymouth NHS TrustPlymouth PL68DHUnited Kingdom Department of Clinical Immunology University Hospitals Plymouth NHS TrustPlymouth PL68DHUnited Kingdom

Alcohol consumption is one of the leading causes of the global burden of disease and results in high healthcare and economic *** alcohol misuse leads to alcohol-related liver disease,which is responsible for a significant proportion of alcohol-attributable deaths *** than reducing alcohol consumption,there are currently no effective treatments for alcohol-related liver *** stress refers to an imbalance in the production and elimination of reactive oxygen species and *** plays important roles in several aspects of alcohol-related liver disease ***,we review how chronic alcohol use results in oxidative stress through increased metabolism via the cytochrome P4502E1 system producing reactive oxygen species,acetaldehyde and protein and DNA *** trigger inflammatory signaling pathways within the liver leading to expression of pro-inflammatory mediators causing hepatocyte apoptosis and *** oxygen species exposure also results in mitochondrial stress within hepatocytes causing structural and functional dysregulation of mitochondria and upregulating apoptotic *** is also evidence that oxidative stress as well as the direct effect of alcohol influences epigenetic *** global histone methylation and acetylation and specific histone acetylation inhibits antioxidant responses and promotes expression of key pro-inflammatory *** review highlights aspects of the role of oxidative stress in disease pathogenesis that warrant further study including mitochondrial stress and epigenetic *** understanding of these processes may identify novel targets for therapy.

关键词： Alcohol-related liver disease Alcoholic hepatitis Oxidative stress Reactive

A three-dimensional feature extraction-based method for coal cleat characterization using X-ray μCT and its application to a Bowen Basin coal specimen

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 153-166页

作者： Yulai Zhang Matthew Tsang Mark Knackstedt Michael Turner Shane Latham euan Macaulay Rhys Pitchers ARC Training Centre for M3D Innovation Research School of PhysicsAustralian National UniversityCanberraACT2601Australia Department of Materials Physics Research School of PhysicsAustralian National UniversityCanberraACT2601Australia Anglo American Steelmaking Coal BrisbaneQLD4000Australia SCT Operations Pty Ltd. WollongongNSW2500Australia

Cleats are the dominant micro-fracture network controlling the macro-mechanical behavior of *** understanding of the spatial characteristics of cleat networks is therefore important to the coal mining *** fracture networks(DFNs)are increasingly used in engineering analyses to spatially model fractures at various *** reliability of coal DFNs largely depends on the confidence in the input cleat *** of these parameters can be made from image-based three-dimensional(3D)characterization of coal cleats using X-ray micro-computed tomography(m CT).One key step in this process,after cleat extraction,is the separation of individual cleats,without which the cleats are a connected network and statistics for different cleat sets cannot be *** this paper,a feature extraction-based image processing method is introduced to identify and separate distinct cleat groups from 3D X-ray m CT ***(filters)representing explicit cleat features of coal are built and cleat separation is successfully achieved by convolutional operations on 3D coal *** new method is applied to a coal specimen with 80 mm in diameter and 100 mm in length acquired from an Anglo American Steelmaking Coal mine in the Bowen Basin,Queensland,*** is demonstrated that the new method produces reliable cleat separation capable of defining individual cleats and preserving 3D topology after ***-parallel fractures are also identified and separated,which has his-torically been challenging to delineate and rarely reported.A variety of cleat/fracture statistics is measured which not only can quantitatively characterize the cleat/fracture system but also can be used for DFN ***,variability and heterogeneity with respect to the core axis are *** heterogeneity is observed and suggests that the representative elementary volume(REV)of the cleat groups for engineering purposes may be a complex problem requ

关键词： Cleat separation Cleat statistics Feature extraction Discrete fracture network(DFN)modeling

The urgent need to cut methane emissions

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National Science Review 2022年第5期9卷 77-78页

作者： euan G.Nisbet Department of Earth Sciences Royal Holloway University of London

Atmospheric methane is a powerful greenhouse gas,surpassed only by COin its human-added warming *** the start of industrialization,when humans began altering the air,the amount of methane in the atmosphere has grown proportionately more than *** 2020,methane’s growth was the highest in the detailed observational record (Fig.1).But although there has been much work on the global methane budget [1],we do not fully understand why this recent growth is taking place,

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Dark mode plasmonic optical microcavity biochemical sensor

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Photonics Research 2019年第8期7卷 939-947页

作者： CHENG LI LEI CHEN euan MCLEOD JUDITH SU College of Optical Sciences University of ArizonaTucsonArizona85721USA State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing100876China Department of Biomedical Engineering University of ArizonaTucsonArizona85721USA

Whispering gallery mode(WGM) microtoroid optical resonators have been effectively used to sense low concentrations of biomolecules down to the single molecule limit. Optical WGM biochemical sensors such as the microtoroid operate by tracking changes in resonant frequency as particles enter the evanescent near field of the ***, gold nanoparticles have been coupled to WGM resonators to increase the magnitude of resonance shifts via plasmonic enhancement of the electric field. However, this approach results in increased scattering from the WGM, which degrades its quality(Q) factor, making it less sensitive to extremely small frequency shifts caused by small molecules or protein conformational changes. Here, we show using simulation that precisely positioned trimer gold nanostructures generate dark modes that suppress radiation loss and can achieve high (> 10~6) Q with an electric-field intensity enhancement of 4300, which far exceeds that of a single rod(~2500 times). Through an overall evaluation of a combined enhancement factor, which includes the Q factor of the system, the sensitivity of the trimer system was improved 105× versus 84× for a single rod. Further simulations demonstrate that unlike a single rod system, the trimer is robust to orientation changes and has increased capture area. We also conduct stability tests to show that small positioning errors do not greatly impact the result.

关键词： WGM Dark mode plasmonic microcavity

A Study of the Velocity Field during Evaporation of Sessile Water and Water/Ethanol Drops

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Journal of Bionic Engineering 2010年第4期7卷 321-328页

作者： John R.E.Christy Khellil Sefiane euan Munro School of Engineering University of Edinburgh

Many studies have investigated evaporation of sessile drops in an attempt to understand the effect of wetting on theevaporation *** interest has also increased in the deposition of particles from such drops,with evaporative massflux being deemed to be responsible for ring-like deposits,and counteraction of the mass flux by Marangoni convection explainingmore uniform deposition *** of such deposition processes is important in biological applications,such as the Litos test-system endorsed by the Russian Ministry of Health for diagnosis of urolithiasis and the evaporation ofcolloidal drops for depositing and organizing proteins and *** most cases where deposition from evaporating drops hasbeen studied,velocity information is inferred from the final deposition pattern or from mathematical modeling based on simplifiedmodels of the physics of the evaporation *** this study we have directly measured the flow velocities in the baseof sessile drops,using micro particle image velocimetry,viewing the drop from below,through the cover *** water drops,a radial pattern of flow was observed with a maximum velocity close to but not at the pinned outer *** ‘azeotropic’ethanol/water mixtures,the velocity field is more chaotic to begin with,passing through a phase involving three or four recirculationcells and finally having the same radial pattern as for water drops.

关键词： evaporation sessile drop velocimetry particle deposition μPIV

The evolution of the atmosphere in the Archaean and early Proterozoic

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Chinese Science Bulletin 2011年第1期56卷 4-13页

作者： NISBET euan FOWLER C Mary R Deptartment of Earth Sciences Royal HollowayUniversity of London

Key steps in atmospheric evolution occurred in the *** Hadean atmosphere was created by the inorganic processes of volatile accretion from space and degassing from the interior,and then modified by chemical and photochemical *** air was probably initially anoxic,though there may have been a supply of oxidation power as a consequence of hydrodynamic escape to space of hydrogen from *** subduction may have removed CO2 and the Hadean planet may have been *** the Archaean,as anoxygenic and then oxygenic photosynthesis evolved,biological activity remade the *** evidence implies there were liquid oceans despite the faint young *** oceans may have been sustained by the greenhouse warming effect of biologically-made *** in the late Archaean would have released free O2 into the *** would have created oxic surface waters,challenging the methane *** the Great Oxidation Event around 2.3 to 2.4 billion years ago,the atmosphere itself became oxic,perhaps triggering a glacial crisis by cutting methane-caused greenhouse *** the early Proterozoic,all the key biochemical processes that maintain the modern atmosphere were probably present in the microbial community.

关键词：晚太古代大气演化早元古代二氧化碳温室效应光化学过程微生物群落调制解调器

The influence of stocking levels,clone,fertilization,and weed control on surface CO_(2)efflux in a mid-rotation Pinus radiata *** plantation in Canterbury,New Zealand

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Journal of Forestry Research 2021年第6期32卷 2567-2575页

作者： Mohan KC euan G.Mason Horacio E.Bown School of Forestry University of CanterburyPrivate Bag 4800ChristchurchNew Zealand Ministry of Industry TourismForests and EnvironmentHetaudaBagmati ProvinceNepal Faculty of Forestry University of ChileP.O.Box 9206SantiagoChile

Silvicultural practices applied in managed forest plantations may help counteract the effects of climate change by influencing soil surface CO_(2)efflux(Fs).Understanding the effects of silvicultural practices on Fs will provide unbiased estimates of carbon fluxes and allow better silvicultural decisions for carbon ***,we assessed how Fs differed seasonally across silvicultural practices(i.e.,stocking levels,clone,fertilization and weed control treatments)and evaluated the effects of soil temperature(Ts)and soil volumetric water content(θv)on Fs across these practices for a mid-rotation(14 year-old)Pinus radiata plantation in the Canterbury region of New *** were significant differences in Fs(p<0.05)over the four seasons,three levels of stocking,and five *** effects of fertilization and weed control applied 12 years previously on Fs were *** estimate of Fs(mean±1 standard deviation)from the study site was 22.7±7.1 t ha^(-1)a^(-1)in the form of CO_(2)(6.2±2.1 t ha^(-1)a^(-1)in the form of C).Fs values were consistently higher in plots with 1250 stems ha^(-1)compared to 2500 stems ha^(-1),which may be related to a strong soil resource limitation because of the close spacing in the latter *** differences in Fs across clones suggest that variations in carbon partitioning might explain their growth *** treatments influenced Fs response to soil temperature(p<0.05),resulting in models explaining 28-49%of the total variance in *** findings provide insights into how silvicultural management decisions may impact Fs in mid-rotation radiata pine plantations,contributing towards developing more precise and unbiased plantation carbon budgets.

关键词： Clone Silvicultural practices Soil CO_(2)efflux Stocking Weed control

Simulating robust far-field coupling to traveling waves in large three-dimensional nanostructured high-Q microresonators

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Photonics Research 2019年第9期7卷 967-976页

作者： LEI CHEN CHENG LI YU-MIN LIU JUDITH SU euan MCLEOD State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing100876China College of Optical Sciences University of ArizonaTucsonArizona85721USA Department of Biomedical Engineering University of ArizonaTucsonArizona85721USA

Ultra-high quality(Q) whispering gallery mode(WGM) microtoroid optical resonators have demonstrated highly sensitive biomolecular detection down to the single molecule limit;however, the lack of a robust coupling method has prevented their widespread adoption outside the laboratory. We demonstrate through simulation that a phased array of nanorods can enable free-space coupling of light both into and out of a microtoroid while maintaining a high Q. To simulate large nanostructured WGM resonators, we developed a new approach known as FloWBEM,which is an efficient and compact 3D wedge model with custom boundary conditions that accurately simulate the resonant Fano interference between the traveling WGM waves and a nanorod array. Depending on the excitation conditions, we find loaded Q factors of the driven system as high as 2.1 × 10~7 and signal-to-background ratios as high as 3.86%, greater than the noise levels of many commercial detectors. These results can drive future experimental implementation.

关键词： domain Simulating robust far-field coupling to traveling waves in large three-dimensional nanostructured high-Q microresonators WGM

Demonising the dingo： How much wild dogma is enough？

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Current Zoology 2011年第5期57卷 668-670页

作者： Mike LETNIC Mathew S. CROWTHER Christopher R. DICKMAN euan G. RITCHIE Hawkesbury Institute for the Environment University of Western Sydney Locked Bag 1797 Penrith NSW 2751 Australia Institute of Wildlife Research School of Biological Sciences University of Sydney NSW 2006 Australia School of Life and Environmental Sciences Deakin University Burwood Victoria 3125 Australia

The roles that top predators play in regulating the structure and function of ecosystems have long been controversial. This is particularly the case when predators pose adverse risks for human life and/or economic interests. The critique of literature on dingoes and their ecological roles in Australia provided by Allen et al. (2011) shows that top predators remain a potentially polarising issue. In opposition to Allen et al. we argue that these widespread patterns of species’ abundances, attributed to the effects of dingoes and evident at scales ranging from the foraging behaviour of individuals through to continental scale patterns of species abundances, constitute strong support for the mesopredator release hypothesis and provide evidence that dingoes benefit biodiversity conservation by inducing community wide trophic cascades. Harnessing the positive ecological effects of dingoes while at the same time minimising their impacts on agriculture is a major socio-political challenge in Australia [Current Zoology57 (5): 668–670].A response to Benjamin L. ALLEN et al. 2011 [Current Zoology, 57 (5):568–583]

关键词：生物多样性保护狗野生物种丰度经济利益澳大利亚生态系统生态作用