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Genesis of Manganese Deposits in the Ali Khanzai Block of the Zhob Ophiolite,Pakistan:Inferences from Geochemistry and Mineralogy

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Journal of Earth Science 2020年第5期31卷 884-895页

作者： Muhammad Ayoub Khan Muhammad Ishaq Kakar Thomas Ulrich Liaqat Ali andrew cKerr Khalid Mahmood Rehanul Haq Siddiqui center of Excellence in Mineralogy University of BalochistanQuettaPakistan Department of Geoscience Aarhus UniversityHoegh-Guldbergs Gade 2QK-8000 Aarhus CDenmark National center of Excellence in Geology University of PeshawarPeshawarPakistan School of Earth and Ocean Sciences Cardijf UniversityCardiffWales CF103 YEUK Department of Earth Sciences、University of Sargodha SargodhaPakistan Balochistan University of Information Technology Engineering and Management SciencesQuettaPakistan

The Zhob ophiolite comprises the Naweoba, Omzha and Ali Khanzai blocks, which are surrounded by the sediments of the Alozai Group and Loralai Formation. The Ali Khanzai Block contains metamorphic, ultramafic, gabbroic, volcanic and volcaniclastic rocks with associated chert. The Zhob manganese deposits found in the Ali Khanzai Block, occur in banded, lenticular and massive forms within red to brown coloured metachert. Braunite and pyrolusite are the main constituent manganese-bearing minerals with minor hausmannite, hematite and barite while quartz is the major gangue mineral with some carbonate minerals. Geochemical evidence from the major oxides indicates that the manganese mineralization and associated metachert at Zhob were formed by hydrothermal activity with little contribution from contemporaneous volcanic materials and this is confirmed by high Fe/Mn and low co/Zn ratios and trace element patterns. These deposits formed along with seafloor spreading centres and were later obducted as part of Ali Khanzai Block of Zhob ophiolite.

关键词： Zhob ophiolite manganese ore hydrothermal genesis

Validation of a discrete element model using magnetic resonance measurements

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Particuology 2009年第4期7卷 297-306页

作者： christoph R.Müller Stuart A.Scott Daniel J.Holland Belinda c.clarke andrew J.Sederman John S.Dennis Lynn F.Gladden Department of chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridge CB2 3RAUnited Kingdom

The discrete element model （DEM） is a very promising modelling strategy for two-phase granular systems. However, owing to a lack of experimental measurements, validation of numerical simulations of two-phase granular systems is still an important issue. In this study, a small two-dimensional gas- fluidized bed was simulated using a discrete element model. The dimensions of the simulated bed were 44mm × 10mm × 120 mm and the fluidized particles had a diameter dp = 1.2 mm and density ρp = 1000 kg/m^3. The comparison between DEM simulations and experiments are performed on the basis of time-averaged voidage maps. The drag-law of Beetstra et al. [Beetstra, R., van der Hoef, M.A., ＆ Kuipers,J. A. M. （2007b）. Drag force of intermediate Reynolds number flow past mono- and bidispersed arrays of spheres. AIchE Journal, 53,489-501 ] seems to give the best results. The simulations are fairly insensitive to the coefficient of restitution and the coefficient of friction as long as some route of energy dissipation during particle-particle and particle-wall contact is provided. changing the boundary condition of the gas phase at the side-walls from zero-slip to full-slip does not affect the simulation results. care is to be taken that the cell sizes are chosen so that a reasonable number of particles can be found in a fluid cell.

关键词： Discrete element modelling Magnetic resonance imaging Voidage Gas-fluidized beds

comparative transcriptomics of central Asian Vitis vinifera accessions reveals distinct defense strategies against powdery mildew

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Horticulture Research 2015年第1期2卷 143-153页

作者： Katherine c H Amrine Barbara Blanco-Ulate Summaira Riaz Dániel Pap Laura Jones Rosa Figueroa-Balderas M andrew Walker Dario cantu Department of Viticulture and Enology University of CaliforniaDavisDavis95616CAUSA Department of Genetics and Plant Breeding Corvinus University of BudapestVillányiút 29-341118BudapestHungary

Grape powdery mildew(PM),caused by the biotrophic ascomycete Erysiphe necator,is a devastating fungal disease that affects most Vitis vinifera *** have previously identified a panel of *** accessions from central Asia with partial resistance to PM that possess a Ren1-like local *** this study,we show that in addition to the typical Ren1-associated late post-penetration resistance,these accessions display a range of different levels of disease development suggesting that alternative alleles or additional genes contribute to determining the outcome of the interaction with the *** identify potential Ren1-dependent transcriptional responses and functions associated with the different levels of resistance,we sequenced and analyzed the transcriptomes of these central Asian accessions at two time points of PM *** were compared to identify constitutive differences and PM-inducible responses that may underlie their disease resistant *** to *** in all resistant accessions were characterized by an early up-regulation of 13 genes,most encoding putative defense functions,and a late down-regulation of 32 genes,enriched in transcriptional regulators and protein *** Ren1-dependent responses included a hotspot of co-regulated genes on chromosome *** also identified 81 genes whose expression levels and dynamics correlated with the phenotypic differences between the most resistant accessions‘Karadzhandahal’,DVIT3351.27,and O34-16 and the other *** study provides a first exploration of the functions associated with varying levels of partial resistance to PM in *** accessions that can be exploited as sources of genetic resistance in grape breeding programs.

关键词： breeding mildew cultivar

An Account of chiral Metal Surfaces and Their Enantiospecific chemistry

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Accounts of Materials Research 2021年第11期2卷 1024-1032页

作者： andrew J.Gellman Department of chemical Engineering and W.E.Scott Institute for Energy Innovation Carnegie Mellon UniversityPittsburghPennsylvania 15213United States

cONSPEcTUS:Molecular chirality has been of scientific interest since 1848 when Pasteur demonstrated its direct connection to the rotation of light by solutions of chiral *** the 1960s the connection was made between the chirality of pharmaceutical compounds and their physiological impact;one enantiomer can be therapeutic while the other is *** realization prompted enormous effort in the synthesis of enantiomerically pure compounds for bioactive use(a$300B/yr market).Until relatively recently,metals were ignored as potential substrates for asymmetric surface chemistry because metals have highly symmetric,achiral bulk structures and the premise was that they could not expose chiral *** 1996,we demonstrated that the high Miller index surfaces of metals can be chiral,existing in two enantiomeric forms M(hkl)R&S,and we hypothesized that they exhibit enantiospecific interactions with chiral *** such intrinsically chiral metal surfaces have ideal structural motifs based on low Miller index terraces separated by kinked monatomic *** Account begins with a short tutorial on the ideal and real structures of chiral metal surfaces to provide a firm basis for understanding the origin of their *** then chronicles the evolution of our understanding of their enantiospecific interactions with chiral adsorbates.

关键词： chiral metals realization

Improving sorghum digestion in broilers by targeting fermentation of xylan

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Animal Nutrition 2022年第3期10卷 198-206页

作者： Natalie K.Morgan andrew Wallace Michael R.Bedford University of New England School of Environmental and Rural ScienceArmidaleNew South WalesAustralia AB Vista Woodstock CourtBlenheim RoadMarlborough Business ParkMarlboroughWiltshireEnglandUnited Kingdom curtin University Kent StreetBentleyWestern AustraliaAustralia

This study was to examine if it is possible to accelerate sorghum digestion in broiler chickens by targeting fermentation of the *** 500 broilers(n=960,80 birds per treatment)were fed 12 sorghumsoybean meal-based dietary treatments fed as 3 phases(starter d 0 to 12,grower d 13 to 23,finisher d 24 to 35),with 8 replicate pens of 10 birds per *** half of the treatments(n=6),10%of the sorghum in the diet was directly replaced with 10%wheat bran,as a source of fermentable *** diets were supplemented with either 0,50 or 2,000 mg/kg xylo-oligosaccharides(XOS),with or without xylanase *** weight gain(BWG),feed intake(FI)and feed conversion corrected for mortality(cFcR)was determined at d 0 to 35,and male and female body weight were measured on d *** d 35,ileum and caeca samples were collected from 2 birds per pen,for determination of caecal cellulase and xylanase activity,microbiota composition and short chain fatty acid(ScFA)concentration,and ileal XOS *** with 2,000 mg/kg XOS caused increased BWG at d 0 to 35(P=0.007)and enhanced caecal propionic,valeric and succinic acid concentration(Pcreased FI(P=0.018)and BWG(P=0.016),as well as caecal Bifidobacteria concentration(Pconcentration was greatest when feeding combined wheat bran,2,000 mg/kg XOS,and xylanase,resulting in increased caecal total ScFA,acetic acid and butyric acid concentration,and xylanase and cellulase activity(Pciency in birds fed sorghum-based diets is improved as a consequence of supplementing with fermentable fibre,xylanase and XOS.

关键词： Xylanase Sorghum Oligosaccharides Broiler

Further compatibility tests of the entomopathogenic fungus Lecanicillium muscarium with conventional insecticide products for control of sweetpotato whitefly, Bemisia tabaci on poinsettia plants

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Insect Science 2008年第4期15卷 355-360页

作者： andrew G. S. cuthbertson Lisa F. Blackburn Phil Northing Weiqi Luo Raymond J. c. cannon Keith F. A. Waiters central Science Laboratory Sand Hutton York Y041 1LZ UK

The effect on spore germination of the entomopathogenic fungus Lecanicillium muscarium following direct exposure for 24 h to the insecticides Majestik, Spray Oil, Agri- 50E, Savona and Oberon for the control of both egg and second instar stages of the sweetpotato whitefly, Bemisia tabaci, was determined. Exposure to both Agri-50E and Oberon was followed by acceptable spore germination. Infectivity rates ofL. muscarium on poinsettia foliage in the presence of dry residues of the insecticides were also investigated. No significant detrimental effects on the levels of control of B. tabaci were recorded compared with fungus applied to residue-free foliage. Sequential application of the chemicals Savona, Spray Oil and Majestik with the fungus all produced mortalities of second instar B. tabaci above 90%. Incorporation of these chemicals with L. muscarium into integrated control programs for B. tabaci is discussed.

关键词： entomopathogenic fungus integrated pest management insecticidecompatibility Lecanicillium muscarium

GPGPU-parallelised hybrid finite-discrete element modelling of rock chipping and fragmentation process in mechanical cutting

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第2期12卷 310-325页

作者： Mojtaba Mohammadnejad Sevda Dehkhoda Daisuke Fukuda Hongyuan Liu andrew chan School of Engineering College of Science and EngineeringUniversity of TasmaniaHobartTAS7001Australia cSIRO Minerals Resources Business UnitQCAT 1 Technology CourtPullenvaleQLD4069Australia Hatch BrisbaneQLD4000Australia Division of Sustainable Resources Engineering Faculty of EngineeringHokkaido UniversityHokkaidoJapan

Mechanical cutting provides one of the most flexible and environmentally friendly excavation *** has attracted numerous efforts to model the rock chipping and fragmentation process,especially using the explicit finite element method(FEM) and bonded particle model(BPM),in order to improve cutting *** study investigates the application of a general-purpose graphic-processing-unit parallelised hybrid finite-discrete element method(FDEM) which enjoys the advantages of both explicit FEM and BPM,in modelling the rock chipping and fragmentation process in the rock scratch test of mechanical rock *** input parameters of FDEM are determined through a calibration procedure of modelling conventional Brazilian tensile and uniaxial compressive tests of limestone,A series of scratch tests with various cutting velocities,cutter rake angles and cutting depths is then modelled using FDEM with calibrated input parameters.A few cycles of cutter/rock interactions,including their engagement and detachment process,are modelled for each case,which is conducted for the first time to the best knowledge of the authors,thanks to the general purpose graphic processing units(GPGPU) *** failure mechanism,cutting force,chipping morphology and effect of various factors on them are discussed on the basis of the modelled ***,it is concluded that GPGPU-parallelised FDEM provides a powerful tool to further study rock cutting and improve cutting efficiencies since it can explicitly capture different fracture mechanisms contributing to the rock chipping as well as chip formation and the separation process in mechanical ***,it is concluded that chipping is mostly owed to the mix-mode Ⅰ-Ⅱ fracture in all cases although mode Ⅱ cracks and mode Ⅰ cracks are the dominant failures in rock cutting with shallow and deep cutting depths,*** chip morphology is found to be a function of cutter velocdty,cutting depth and cutter rake angl

关键词： Numerical simulation Finite-discrete element method(FDEM) Rock cutting chipping cracking

computational comparison of One Piece Metacarpo-Phalangeal/Phalangeal-Phalangeal Total Joint Replacements

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Journal of Biomedical Science and Engineering 2014年第7期7卷 427-433页

作者： andrew c. Weems Ha Van Vo Department of Biomedical Engineering Mercer University Macon USA

Trauma, osteoarthritis and rheumatoid arthritis can destroy the articulating cartilage in small and large joints, especially in the metacarpo [tarso] phalangeal (McP/MTP) and phalangeal-phalangeal (PIP) joints. Single piece finger prosthetic designs can reduce pain and correct aesthetic issues, with problems on contemporary designs including decreased stability, lack of fixation and loss of functionality. The examined implants are representative models of currently available total joint replacement (TJR) designs for McP replacement, such as the Swanson one piece implant. These implants have been shown clinically to have a high failure rate (up to 90%), but the cause of failure is unknown. compressive studies using a 50 N force and medial-lateral loads of 50 N perpendicular to the longitudinal axis of the arms of the implant were individually applied. Due to material failings, lower values had to be used in some cases. Maximum stress values were found for flexion loading;the Swanson approximation had a peak stress of 8.71 GPa at the interface of the joint arm and the flexion center, Neuflex had 0.188 GPa peak stress at the fixation center of the arm, and in the center of the joint, and the Avanta design had a 5.20 GPa peak stress at the flexion center. The location and concentration of stresses on the models correspond to literature searches for clinical data, showing that the main failure mechanism for these implants is due to primary flexion-extension natural movement of the joint.

关键词： Metacarpo-Phalangeal Joint Phalangeal Joint Finger Prostheses Total Joint Replacement computational Modeling Swanson Avanta NeuFlex

Genomic surveillance of Nevada patients revealed prevalence of unique SARS-coV-2 variants bearing mutations in the RdRp gene

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Journal of Genetics and Genomics 2021年第1期48卷 40-51页

作者： Paul D.Hartley Richard L.Tillett David P.Aucoin Joel R.Sevinsky Yanji Xu andrew Gorzalski Mark Pandori Erin Buttery Holly Hansen Michael A.Picker cyprian c.Rossetto Subhash c.Verma Nevada Genomics center RenoNV 89557USA University of Nevada RenoRenoNV 89557USA Nevada Institute of Personalized Medicine University of NevadaLas VegasNV 89154USA Department of Microbiology&Immunology University of NevadaReno School of MedicineRenoNV 89557USA Theiagen consulting LLCHighlands RanchCO 80128USA Nevada center for Bioinformatics RenoNV 89557USA Nevada State Public Health Laboratory RenoNV 89503USA Southern Nevada Public Health Laboratory of the Southern Nevada Health District Las VegasNV 89107USA

Patients with signs of cOVID-19 were tested through diagnostic RT-PcR for SARS-coV-2 using RNA extracted from the nasopharyngeal/nasal *** determine the variants of SARS-coV-2 circulating in the state of Nevada,specimens from 200 cOVID-19 patients were sequenced through our robust sequencing platform,which enabled sequencing of SARS-coV-2 from specimens with even very low viral loads,without the need of culture-based *** genome coverage allowed the identification of single and multi-nucleotide variants in SARS-coV-2 in the community and their phylogenetic relationships with other variants present during the same period of the *** report the occurrence of a novel mutation at 323aa (314aa of orf1b) of nsp12 (RNA-dependent RNA polymerase) changed to phenylalanine(F) from proline (P),in the first reported isolate of SARS-coV-2,*** 323F variant was present at a very high frequency in Northern *** modeling determined this mutation in the interface domain,which is important for the association of accessory proteins required for the *** conclusion,we report the introduction of specific SARS-coV-2 variants at very high frequency in distinct geographic locations,which is important for understanding the evolution and circulation of SARS-coV-2variants of public health importance,while it circulates in humans.

关键词： SARS-coV-2 cOVID-19 Genome enrichment nsp12 RdRp orf1b 314