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Chinese j.urnal of Cancer 2011年第4期30卷 247-253页

作者： David Cogdell Woonbok Chung Yuexin Liu j. matthew mcdonald Kenneth Aldape j.an-Pierre j. Issa Gregory N. Fuller Wei Zhang Department of Pathology The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA Department of Leukemia The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA.

Allelic loss of the short arm of chromosome 1 has been observed frequently in a wide spectrum of cancers,most frequently in *** our previous studies,we evaluated 177 oligodendroglial tumor samples and identified the Aj.P1 gene(formerly Shrew1) in the consensus region of ***1 is a transmembrane protein found in adheren j.nctions and functions to inhibit glioma cell adhesion and *** a putative tumor suppressor gene,we did not detect Aj.P1 gene *** subsequent studies,we found that Aj.P1 was underexpressed in oligodendrogliomas relative to normal brain *** analysis revealed the presence of CpG islands in the promoter of *** analysis of the Aj.P1 promoter identified hypermethylation in 21% of oligodendrogliomas(n = 27),and the degree of methylation correlated with low levels of Aj.P1 expression(P = 0.045).The Aj.P1 promoter was also highly methylated in a wide spectrum of cell lines(n = 22),including cell lines of *** of the National Cancer Institute's REMBRANDT dataset,which contains 343 glioma samples,indicated that low Aj.P1 gene expression was associated with decreased ***,both genetic(gene deletion) and epigenetic alterations(promoter methylation) are likely mechanisms that inactivate the putative tumor suppressor Aj.P1 in gliomas,which contributes to poor prognosis.

关键词：甲基化分析脑胶质瘤抑癌基因 P1基因肿瘤患者协会少突胶质细胞

Preliminary Insights into the Habitat Preferences of the Centralian Bandy Bandy (Vermicella vermiformis)(Squamata: Elapidae) in Central Australia

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Asian Herpetological Research 2014年第1期5卷 49-53页

作者： Peter j.mcdonald Gary W.LUCK Flora and Fauna Division Department of Land Resource Management Northern Territory Government School of Environmental Sciences Charles Sturt University Institude for Land Water and Society Charles Sturt University

Bandy Bandy’s（Vermicella spp.）are a striking,black-and-white ringed genus of small elapid snakes endemic to *** taxa are burrowers and little is known of their biology and *** investigated the habitat preferences of the only arid-dwelling species,the centralian bandy bandy（Vermicella vermiformis）,in the MacDonnell Ranges west of Alice Springs in the Northern *** systematic road-cruising,we encountered *** over a 12 months period between 2009 and *** used logistic regression to model the occurrence of the species against a range of different habitat variables collected at multiple *** the small sample size,*** exhibited a clear preference for acacia shrubland habitats,with acacia variables present in all AICc ranked models in the 95%confidence *** factors driving this association,together with the preference for habitat not burnt in the most recent wildfires,may be related to the abundance of their only known prey,blind snakes（Ramphotyphlops spp.）.

关键词： Snake Arid Acacia Fire Ramphotyphlops

Decreased bioavailability of aminomethylphosphonic acid(AMPA)in genetically modified corn with activated carbon or calcium montmorillonite clay inclusion in soil

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j.urnal of Environmental Sciences 2021年第2期33卷 131-143页

作者： Sara E.Hearon Meichen Wang Thomas j.mcdonald Timothy D.Phillips Veterinary Integrative Biosciences Department College of Veterinary Medicine and Biomedical Sciences Texas A&M Uniuersity College StationTx 77845USA Department of Environmental and Occupational Health School of Public Health Texas A&M UniversityCollege Station400 Bizzell St College StationTX 77843USA

The widespread use of pesticides has resulted in detectable residues throughout the environment,sometimes at concentrations well above regulatory ***,the development of safe,effective,field-practical,and economically feasible strategies to mitigate the effects of pesticides is *** is an organophosphorus herbicide that is degraded to aminomethylphosphonic acid(AMPA),a toxic and persistent metabolite that can accumulate in soil and sediment and translocate to *** this study,we investigated the binding efficacy of activated carbon(AC)and calcium montmorillonite(CM)clay to decrease AMPA bioavailability from soil and AMPA translocation to *** isotherms and thermodynamic studies on AC and CM were conducted and showed tight binding(enthalpy values>-20 k j.mol)for AMPA with high capacities(0.25 mol/kg and 0.38 mol/kg,respectively),based on derivations from the Langmuir model.A hydra assay was utilized to indicate toxicity of AMPA and the inclusion of 1%AC and CM both resulted in 90%protection of the hydra(**p≤0.01).Further studies in glyphosate-contaminated soil showed that AC and CM significantly reduced AMPA bioavailability by 53%and 44%,*** in genetically modified(GM)corn showed a conversion of glyphosate to AMPA in roots and sprouts over a 10-day exposure *** of AC and CM reduced AMPA residues in roots and sprouts by 47%-61%.These studies collectively indicate that AC and CM are effective sorbents for AMPA and could be used to reduce AMPA bioavailability from soil and AMPA residues in GM corn plants.

关键词： Glyphosate AMPA Activated carbon Calcium montmorillonite Sorbent

4D imaging of void nucleation,growth,and coalescence from large and small inclusions in steel under tensile deformation

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j.urnal of Materials Science & Technology 2022年第28期123卷 168-176页

作者： Yi Guo Timothy L.Burnett Samuel A.mcdonald Michael Daly Andrew H.Sherry Philip j.Withers Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Henry Royce Institute Department of MaterialsUniversity of ManchesterM139PLUK European Synchrotron Radiation Facility(ESRF) 6 rue J Horowitz38000 GrenobleFrance National Nuclear Laboratory Chadwick HouseBirchwood ParkWarringtonWA36AEUK

Samples of SA508 grade 3 nuclear pressure vessel ferritic steel were subj.cted to tensile straining whilst being simultaneously imaged in 3D in real time using high resolution,high frame rate time-lapse synchrotron computed tomography(CT).This enabled direct observation of void development from nucleation,through growth to coalescence and final failure validating many inferences made post-mortem or by theoretical models,as well as raising new *** sparse,large inclusions were found to nucleate voids at essentially zero plastic strain(consistent with zero interfacial strength);these became increasingly elongated with *** contrast,a high density of small spherical voids were found to nucleate from the sub-micron cementite particles at larger strains(>200%)only in the centre of the necked(high triaxiality)*** interfacial strength approaching 2100 MPa was inferred and soon after their nucleation,these small voids coalesce to form internal microcracks that lead to the final failure of the *** surprisingly,under these conditions of generally low triaxial constraint the large voids are simply cut across and appear to play no significant role in determining the final *** implications of these results are discussed in terms of ductile fracture behaviour and the Gurson model for ductile fracture.

关键词： Void growth Ductile fracture Synchrotron X-ray tomography 4D imaging Bainitic steel

Elimination of antibiotic resistance genes and control of horizontal transfer risk by UV-based treatment of drinking water: A mini review

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 3-11页

作者： Virender K.Sharma Xin Yu Thomas j.mcdonald Chetan j.nadatha Dionysios D.Dionysiou Mingbao Feng Department of Environmental and Occupational Health School of Public Health Texas A&M University College Station TX 77843 USA Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China Central Texas Veterans Health Care System Temple TX 76504 USA College of Medicine Texas A&M Health Science Center Bryan TX 77807 USA Environmental Engineering and Science Program Department of Chemical and Environmental Engineering (DChEE) 705 Engineering Research Center University of Cincinnati Cincinnati OH 45221 USA

Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) have been recognized as one of the biggest public health issues of the 21 st century. Both ARB and ARGs have been determined in water after treatment with conventional disinfectants. Ultraviolet (UV) technology has been seen growth in application to disinfect the water. However, UV method alone is not adequate to degrade ARGs in water. Researchers are investigating the combination of UV with other oxidants (chlorine, hydrogen peroxide (H2O2), peroxymonosulfate (PMS), and photocatalysts) to harness the high reactivity of produced reactive species (C1-, C1O -, Cl2-,-OH, and SO4-_) in such processes with constituents of cell (e.g., deoxyribonucleic acid (DNA) and its components) in order to increase the degradation efficiency of ARGs. This paper briefly reviews the current status of different UV-based treatments (UV/chlorination, UV/H2O2, UV/PMS, and UV-photocatalysis) to degrade ARGs and to control horizontal gene transfer (HGT) in water. The review also provides discussion on the mechanism of degradation of ARGs and application of q-PCR and gel electrophoresis to obtain insights of the fate of ARGs during UV-based treatment processes.

关键词： Antibiotic resistance bacteria Advanced oxidation processes Disinfection Reactive chlorine species Sulfate radicals Reactive oxygen species

A bayesian optimisation methodology for the inverse derivation of viscoplasticity model constants in high strain-rate simulations

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Defence Technology（防务技术） 2022年第9期18卷 1563-1577页

作者： Shannon Ryan j.lian Berk Santu Rana Brodie mcdonald Svetha Venkatesh Applied Artificial Intelligence Institute(A^(2)I^(2)) Deakin University75 Pigdons RdWaurn PondsVIC3216Australia Defence Science and Technology Group 506 Lorimer StreetFishermans BendVIC3207Australia

We present an inverse methodology for deriving viscoplasticity constitutive model parameters for use in explicit finite element simulations of dynamic processes using functional experiments, i.e., those which provide value beyond that of constitutive model development. The developed methodology utilises Bayesian optimisation to minimise the error between experimental measurements and numerical simulations performed in LS-DYNA. We demonstrate the optimisation methodology using high hardness armour steels across three types of experiments that induce a wide range of loading conditions: ballistic penetration, rod-on-anvil, and near-field blast deformation. By utilising such a broad range of conditions for the optimisation, the resulting constitutive model parameters are generalised, i.e., applicable across the range of loading conditions encompassed the by those experiments(e.g., stress states, plastic strain magnitudes, strain rates, etc.). Model constants identified using this methodology are demonstrated to provide a generalisable model with superior predictive accuracy than those derived from conventional mechanical characterisation experiments or optimised from a single experimental condition.

关键词： Constitutive modelling Finite element Bayesian optimisation Finite element model updating

The complexity of sediment recycling as revealed by common Pb isotopes in K-feldspar

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Geoscience Frontiers 2018年第5期9卷 1515-1527页

作者： Simon P.j.hnson Christopher L.Kirkland Noreen j.Evans Brad j.mcdonald Huntly N.Cutten Geological Survey of Western Australia Mineral House100 Plain StreetEast PerthWestern Australia6004Australia Centre for Exploration Targeting-Curtin Node The Institute for Geoscience ResearchDepartment of Applied GeologyWestern Australian School of MinesCurtin UniversityPerthWestern Australia6102Australia j.hn de Laeter Centre The Institute for Geoscience ResearchDepartment of Applied Geology and Applied PhysicsCurtin UniversityPerthWestern Australia6102Australia

Detrital zircon U-Pb geochronology has become the gold standard in evaluating source to sink relationships in sedimentary basins. However, the physical and chemical robustness of zircon, which make it such a useful mineral for provenance studies, is also a hindrance as zircon can be recycled through numerous sedimentary basins, thus obscuring the first cycle source to sink relationship. An elegant approach to addressing this potential issue is to compare the Pb isotope composition of detrital K-feldspar, a mineral which is unlikely to survive more than one erosion-transport-deposition cycle, with that of magmatic K-feldspar from potential basement source terranes. Here we present new in situ Pb isotope data on detrital K-feldspar from two Proterozoic arkosic sandstones from Western Australia, and magmatic K-feldspar grains from potential igneous source rocks, as inferred by the age and Hf isotope composition of detrital zircon grains. The data indicate that the detrital zircon and K-feldspar grains could not have been liberated from the same source rocks, and that the zircon has most likely been recycled through older sedimentary basins. These results provide a more complete understanding of apparently simple source to sink relationships in this part of Proterozoic Western Australia.

关键词： Detrital zircon K-feldspar Pb isotopes Sediment provenance Sediment recycling

Wet Pressing Models to Reduce Energy Consumption in Papermaking

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Paper And Biomaterials 2019年第1期4卷 1-6页

作者： j.David mcdonald Richard j.Kerekes j.e R.Zhao j.McD Consulting Inc. Vaudreuil-Dorion Quebec J7V 0G1 Canada Pulp and Paper Centre the University of British Columbia Vancouver BC V6T 1Z4 Canada Tri-Y Environmental Research Institute Vancouver BC V5M 3H9 Canada

Improved wet pressing reduces the need for drying and consequently energy needed in papermaking. Accordingly, it is desirable to optimize wet pressing, but the process is very complex with many interacting variables. It is therefore desirable to employ a mathematical model that accounts for the maj.r variables to estimate the effects of changes in equipment and operating variables. This paper descibes such a model called the Decreasing Permeability Model (DPM). Mill and pilot plant applications over a wide range of basis weights for paper and paper board are described.

关键词： wet pressing Decreasing Permeability Model (DPM) papermaking water removal rewet mathemeitical model

Neurological heterotopic ossification:novel mechanisms,prognostic biomarkers and prophylactic therapies

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Bone Research 2020年第4期8卷 379-392页

作者： Ker Rui Wong Richelle Mychasiuk Terence j.O’Brien Sandy R.Shultz Stuart j.mcdonald Rhys D.Brady Department of Neuroscience Central Clinical SchoolMonash UniversityMelbourneVICAustralia Department of Medicine Royal Melbourne HospitalThe University of MelbourneParkvilleVICAustralia Department of Physiology Anatomy and MicrobiologySchool of Life SciencesLa Trobe UniversityBundooraVICAustralia

Neurological heterotopic ossification(NHO)is a debilitating condition where bone forms in soft tissue,such as muscle surrounding the hip and knee,following an inj.ry to the brain or spinal *** abnormal formation of bone can result in nerve impingement,pain,contractures and impaired *** are often diagnosed with NHO after the bone tissue has completely mineralised,leaving invasive surgical resection the only remaining treatment *** resection of NHO creates potential for added complications,particularly in patients with concomitant inj.ry to the central nervous system(CNS).Although recent work has begun to shed light on the physiological mechanisms involved in NHO,there remains a significant knowledge gap related to the prognostic biomarkers and prophylactic treatments which are necessary to prevent NHO and optimise patient *** article reviews the current understanding pertaining to NHO epidemiology,pathobiology,biomarkers and treatment *** particular,we focus on how concomitant CNS inj.ry may drive ectopic bone formation and discuss considerations for treating polytrauma patients with *** conclude that understanding of the pathogenesis of NHO is rapidly advancing,and as such,there is the strong potential for future research to unearth methods capable of identifying patients likely to develop NHO,and targeted treatments to prevent its manifestation.

关键词： such has likely

A machine learning approach for regional geochemical data:Platinum-group element geochemistry vs geodynamic settings of the North Atlantic Igneous Province

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Geoscience Frontiers 2021年第3期12卷 42-59页

作者： j.rdan j.Lindsay Hannah S.R.Hughes Christopher M.Yeomans j.ns C.Ø.Andersen Iain mcdonald Camborne School of Mines University of ExeterPenryn CampusPenrynCornwall TR109FEUnited Kingdom School of Earth and Ocean Sciences Main CollegeCardiff UniversityPark PlaceCardiff CF103ATUnited Kingdom

Whilst traditional approaches to geochemistry provide valuable insights into magmatic processes such as melting and element fractionation,by considering entire regional data sets on an obj.ctive basis using machine learning algorithms(MLAs),we can highlight new facets within the broader data structure and significantly enhance previous geochemical *** platinum-group element(PGE)budget of lavas in the North Atlantic Igneous Province(NAIP)has been shown to vary systematically according to age,geographic location and geodynamic *** the large multi-element geochemical data set available for the region,MLAs were employed to explore the magmatic controls on these shifting *** key advantage of using machine learning in analysis is its ability to cluster samples across multi-dimensional(i.e.,multi-element)*** NAIP data set is manipulated using Principal Component Analysis(PCA)and t-Distributed Stochastic Neighbour Embedding(t-SNE)techniques to increase separability in the data alongside clustering using the k-means *** new multi-element classification is compared to the original geographic classification to assess the performance of both *** workflow provides a means for creating an obj.ctive high-dimensional investigation on a geochemical data set and particularly enhances the identification of metallogenic anomalies across the *** techniques used highlight three distinct multi-element end-members which successfully capture the variability of the maj.rity of elements included as input *** end-members are seen to fluctuate in prominence throughout the NAIP,which we propose reflects the changing geodynamic environment and melting ***,the variability of Pt and Pd are not reflected in MLA-based clustering trends,suggesting that they vary independently through controls not readily demonstrated by the NAIP maj.r or trace element data structure(i.e.,other proxies for magmatic differe

关键词： Platinum-group elements Machine learning Plume Geochemistry Metallogenesis Mantle