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A comparison of the ballistic behaviour of conventionally sintered and additively manufactured alumina

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Defence Technology（防务技术） 2020年第2期16卷 275-282页

作者： Gareth james Appleby-Thomas Kevin Jaansalu Amer Hameed Jonathan Painter james Shackel Julie Rowley Centre for Defence Engineering Cranfield Defence and SecurityCranfield UniversityShrivenhamSwindonSN68LAUK Department of Chemistry and Chemical Engineering Royal Military College of CanadaPO Box 17000Station ForcesKingstonOntarioK7K 7B4Canada

Production of ceramic armour solutions on-demand/in-theatre would have significant logistical and military ***,even assuming that such technologies could be successfully deployed in the field,such near net-shape manufacturing technology is relatively immature compared to conventional sintering of *** this study,the ballistic performance of a series of additively manufactured(Am)/rapidly-prototyped(RP)alumina tiles of 97.2%of the density of Sintox FATm were investigated using both forward-and reverse-ballistic *** experiments,undertaken with compressed gasguns,employed the depth-of-penetration technique and flash X-ray as primary diagnostics to interrogate both efficiency of penetration and projectile-target interaction,*** RP alumina was found to exhibit useful ballistic properties,successfully defeating steel-cored(AP)7.62×39 mm BXN rounds at velocities of up-to c.a.850 m/s,while exhibiting comparable failure modes to conventionally sintered armour-grade Sintox ***,where amaterial failure modes changed dramatically with performance dropping below that of conventionally sintered ***,the results from both sets of experiments were complimentary and clearly indicated the potential of such RP materials to play an active role in provision of real-world body armour solutions provided quality control of the RP material can be maintained.

关键词： Additive manufacture Rapidly prototyped Body armour Ballistics Ceramics

Engineering Nitrogenases for Synthetic Nitrogen Fixation:From Pathway Engineering to Directed Evolution

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BioDesign Research 2023年第1期5卷 25-36页

作者： Emily m.Bennett james W.murray mark Isalan Department of Life Sciences Imperial College LondonLondon SW72AZUK.

Globally,agriculture depends on industrial nitrogen fertilizer to improve crop *** production consumes fossil fuels and contributes to environmental nitrogen pollution.A potential solution would be to harness nitrogenases—enzymes capable of converting atmospheric nitrogen N2 to NH3 in ambient *** is therefore a major goal of synthetic biology to engineer functional nitrogenases into crop plants,or bacteria that form symbiotic relationships with crops,to support growth and reduce dependence on industrially produced *** review paper highlights recent work toward understanding the functional requirements for nitrogenase expression and manipulating nitrogenase gene expression in heterologous hosts to improve activity and oxygen tolerance and potentially to engineer synthetic symbiotic relationships with plants.

关键词： crops synthetic Evolution

A comparison of the relative efficiency of ICSI and extended culture with epididymal sperm versus testicular sperm in patients with obstructive azoospermia

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Asian Journal of Andrology 2020年第2期22卷 222-226页

作者： Scott J morin Brent m Hanson Caroline R Juneau Shelby A Neal Jessica N Landis Richard T Scott Jr james m Hotaling Reproductive medicine Associates of New Jersey 140 Allen RoadBasking RidgeNJ 07920USA Division of Reproductive Endocrinology and Infertility Department of Obstetrics and GynecologySidney Kimmel Medical College at Thomas Jefferson University833 Chestnut StreetPhiladelphiaPA 19107USA Foundation for Embryonic Competence 140 Allen RoadBasking RidgeNJ 07920USA Division of Urology Department of SurgeryUniversity of Utah School of Medicine30 N 1900 ESalt Lake CityUT 84132USA Department of Obstetrics and Gynecology University of Utah School of Medicine30 N 1900 ESalt Lake CityUT 84132USA.An abbreviated version of this manuscript was published and presented as an abstract at the American Society for Reproductive Medicine(ASRM)2017 Scientific Congress.

This is a retrospective cohort study comparing blastocyst transfer outcomes following intracytoplasmic sperm injection utilizing epididymal versus testicular sperm for men with obstructive *** cases at a single center between 2012 and 2016 were *** approach was selected at the surgeon’s discretion and included microepididymal sperm aspiration or testicular sperm *** culture was exclusively utilized prior to *** primary outcome was live birth *** outcomes included fertilization rate,blastulation rate,euploidy rate,and implantation rate.A mixed effects model was ***-six microepididymal sperm aspiration cases and 93 testicular sperm extraction cases were *** live birth rate was equivalent(48.6%vs 50.5%,P=0.77).However,on mixed effects model,epididymal sperm resulted in a greater likelihood of fertilization(adjusted OR:1.37,95%CI:1.05–1.81,P=0.02)and produced a higher blastulation rate(adjusted OR:1.41,95%CI:1.1–1.85,P=0.01).As a result,the epididymal sperm group had more supernumerary blastocysts available(4.3 vs 3,Pmic sperm injection following microepididymal sperm aspiration resulted in a greater number of usable blastocysts per ***,the true benefit of epididymal sperm may only be demonstrated via a comparison of cumulative pregnancy rates after multiple transfers from one cohort.

关键词： azoospermia intracytoplasmic sperm injection male infertility testicular sperm extraction

Effects of a blend of Saccharomyces cerevisiae-based direct-fed microbial and fermentation products on plasma carbonylmetabolome and fecal bacterial community of beef steers

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Journal of Animal Science and Biotechnology 2020年第2期11卷 504-513页

作者： james A.Adeyemi Sunday O.Peters marcos De Donato Andres Pech Cervantes Ibukun m.Ogunade College of Agriculture Communitiesand the EnvironmentKentucky State UniversityFrankfortKY 40601USA Department of Animal Science Berry CollegeMount BerryGA 30149USA Tecnologico de monterrey Escuela de Ingenieria y CienciasQueretaroMexico Agricultural Research Station Fort Valley State UniversityFort ValleyGA 31030USA

Background:Previous studies have evaluated the metabolic status of animals fed direct-fed microbial(DFm)using enzyme-based assays which are time-consuming and limited to a few *** addition,little emphasis has been placed on investigating the effects of DFm on hindgut *** examined the effects of dietary supplementation of a blend of Saccharomyces cerevisiae-based DFm and fermentation products on the plasma concentrations of carbonyl-containing metabolites via a metabolomics approach,and fecal bacterial community,via 16S rRNA gene sequencing,of beef steers during a 42-day receiving *** newly weaned steers were randomly assigned to receive a basal diet with no additive(CON;n=20)or a basal diet supplemented with 19 g of Commence™(PROB;n=20)for a 42-day ***™(PmI,Arden Hills,mN)is a blend of 6.2×1011 cfu/g of ***,3.5×1010 cfu/g of a mixture of Enterococcus lactis,Bacillus subtilis,Enterococcus faecium,and Lactobacillus casei,and the fermentation products of these aforementioned microorganisms and those of Aspergillus oryzae and Aspergillus *** d 0 and 40,rectal fecal samples were collected randomly from 10 steers from each treatment *** d 42,blood was collected for plasma ***:A total number of 812 plasma metabolites were *** to 305 metabolites[fold change(FC)≥1.5,FDR≤0.01]including glucose,hippuric acid,and 5-hydroxykynurenamine were increased by PROB supplementation,whereas 199 metabolites(FC≤0.63,FDR≤0.01)including acetoacetate were *** of PROB increased(P≤0.05)the relative abundance of Prevotellaceae UCG-003,megasphaera,Dorea,Acetitomaculum,and *** contrast,the relative abundance of Elusimicrobium,moheibacter,Stenotrophomonas,Comamonas,and uncultured bacterium belonging to family p-2534-18B5 gut group(phylum Bacteroidetes)were reduced(P≤0.05).Conclusions:The results of this study demonstrated that supplementation of PROB altered both the plasma carbonyl metab

关键词： Beef steer Carbonyl Fecal bacteria Lactate-utilizing bacteria Plasma metabolomics

mafic Archean continental crust prohibited exhumation of orogenic UHP eclogite

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Geoscience Frontiers 2021年第5期12卷 411-420页

作者： Richard m.Palin james D.P.moore Zeming Zhang Guangyu Huang Jon Wade Brendan Dyck Department of Earth Sciences University of OxfordOxford OX13ANUnited Kingdom Earth Observatory of Singapore Nanyang Technological UniversitySingapore Institute of Geophysics SGEESVictoria University of WellingtonWellingtonNew Zealand Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Department of Earth Environmental and Geographical SciencesUniversity of British ColumbiaKelowna V1V 1V7Canada

The absence of ultrahigh pressure(UHP)orogenic eclogite in the geological record older than c.0.6 Ga is problematic for evidence of subduction having begun on Earth during the Archean(4.0-2.5 Ga).many eclogites in Phanerozoic and Proterozoic terranes occur as mafic boudins encased within low-density felsic crust,which provides positive buoyancy during subduction;however,recent geochemical proxy analysis shows that Archean continental crust was more mafic than previously thought,having greater proportions of basalt and komatiite than modern-day ***,we show via petrological modelling that secular change in the petrology and bulk composition of upper continental crust would make Archean continental terranes negatively buoyant in the mantle before reaching UHP *** or delaminated Archean continental crust passes a point of no return during metamorphism in the mantle prior to the stabilization of coesite,while Proterozoic and Phanerozoic terranes remain positively buoyant at these *** orogenic eclogite may thus readily have formed on the Archean Earth,but could not have been exhumed,weakening arguments for a Neoproterozoic onset of subduction and plate ***,isostatic balance calculations for more mafic Archean continents indicate that the early Earth was covered by a global ocean over 1 km deep,corroborating independent isotopic evidence for large-scale emergence of the continents no earlier than c.3 *** findings thus weaken arguments that early life on Earth likely emerged in shallow subaerial ponds,and instead support hypotheses involving development at hydrothermal vents in the deep ocean.

关键词： Archean Eclogite Exhumation Secular change Geodynamics Density

Predicting Carpark Prices Indices in Hong Kong Using AutomL

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Computer modeling in Engineering & Sciences 2023年第3期134卷 2247-2282页

作者： Rita Yiman Li Lingxi Song Bo Li m.james C.Crabbe Xiao-Guang Yue Sustainable Real Estate Research Center Hong Kong Shue Yan UniversityHong Kong999077China Chakrabongse Bhuvanarth International Institute for Interdisciplinary Studies Rajamangala University of Technology Tawan-OkBangkok10400Thailand Zhongyuan Region Company Jinke Property Group Co.Ltd.Zhengzhou450000China Wolfson College Oxford UniversityOxfordOX26UDUK Institute of Biomedical and Environmental Science&Technology University of BedfordshireLutonLU13JUUK School of Life Sciences Shanxi UniversityTaiyuan030006China Department of Computer Science and Engineering European University CyprusNicosia1516Cyprus

The aims of this study were threefold:1)study the research gap in carpark and price index via big data and natural language processing,2)examine the research gap of carpark indices,and 3)construct carpark price indices via repeat sales methods and predict carpark indices via the *** researching the keyword“carpark”in Google Scholar,the largest electronic academic database that coversWeb of Science and Scopus indexed articles,this study obtained 999 articles and book chapters from 1910 to *** confirmed that most carpark research threw light on multi-storey carparks,management and ventilation systems,and reinforced concrete *** most common research method was case *** price index research,many previous studies focused on consumer,stock,press and futures,with many keywords being related to finance and *** indicated that there is no research predicting carpark price indices based on an AutomL *** study constructed repeat sales indices for 18 districts in Hong Kong by using 34,562 carpark transaction records from December 2009 to June ***’s carpark price was about four times that of Yuen Long’s carpark price,indicating the considerable carpark price differences inHong *** research evidenced the features that affected the carpark price indices models most:gold price ranked the first in all 19 models;oil price or Link stock price ranked second depending on the district,and carpark affordability ranked third.

关键词： Carpark repeat sales index AutomL Hong Kong natural language processing tokenization

Arsenic variability and groundwater age in three water supply wells in southeast New Hampshire

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Geoscience Frontiers 2019年第5期10卷 1669-1683页

作者： Joseph P.Levitt james R.Degnan Sarah m.Flanagan Bryant C.Jurgens U.S.Geological Survey

Three wells in New Hampshire were sampled bimonthly over three years to evaluate the temporal variability of arsenic concentrations and groundwater *** samples had measurable concentrations of arsenic throughout the entire sampling period and concentrations in individual wells had a mean variation of more than 7 μg/*** time series data from this sampling effort showed that arsenic concentrations ranged from a median of 4 mg/L in a glacial aquifer well (SGW-65) to medians of 19 μg/L and 37 μg/L in wells (SGW-93 and KFW-87) screened in the bedrock aquifer,*** high arsenic concentrations were associated with the consistently high pH (median ≥- 8) and low dissolved oxygen (median mg/L) in the bedrock aquifer wells,which is typical of fractured crystalline bedrock aquifers in New *** from the glacial aquifer often has high dissolved oxygen,but in this case was consistently *** pH also is generally acidic in the glacial aquifer but in this case was slightly alkaline (median =7.5).Also,sorption sites may be more abundant in glacial aquifer deposits than in fractured bedrock which may contribute to lower arsenic *** groundwater ages were less than 50 years old in all three wells and correlated with conservative tracer concentrations,such as chloride;however,mean age was not directly correlated with arsenic *** concentrations at KFW-87 did correlate with water levels,in addition,there was a seasonal pattern,which suggests that either the timing of or multiple sampling efforts may be important to define the full range of arsenic concentrations in domestic bedrock *** geochemically reduced conditions and alkaline pHs are common to both bedrock and glacial aquifer wells in this study,groundwater age correlates less strongly with arsenic concentrations than geochemical *** also is evidence of direct hydraulic connection between the glacial and bedrock aquifers,which can influe

关键词： Arsenic variability Geochemical time series Age tracers Groundwater age modeling

Visible light photocatalytic bismuth oxide coatings are effective at suppressing aquatic cyanobacteria and degrading free-floating genomic DNA

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Journal of Environmental Sciences 2021年第6期33卷 128-136页

作者： james Redfern marina Ratova Andrew PDean james Pritchett matthieu Grao Joanna Verran Peter Kelly Department of Natural Sciences Faculty of Science and EngineeringManchester Metropolitan UniversityChester StreetM15GDUK Surface Engineering Group Faculty of Science and EngineeringManchester Metropolitan UniversityChester StreetM15GDUK Department of Life Sciences Faculty of Science and EngineeringManchester Metropolitan UniversityChester StreetM15GDUK

Access to safe drinking water free from microbial pollution is an issue of global concern. The use of photocatalytic thin films in water treatment has focused on titanium dioxide, which requires UV-activation, proving a potential barrier to upscaling and implementation in the real world. Visible-light-activated photocatalytic thin films, such as bismuth oxide, have recently been shown to have antimicrobial properties. However, more understanding of the photocatalytic effect on the microbial population in water is required. Glass beads coated with bismuth oxide were incubated with either microcystis aeruginosa, Anabaena sp. or free-floating genomic DNA. The presence of bismuth oxide-coated glass beads was able to rapidly stop a population of cyanobacteria from increasing. The coated beads were also able to degrade genomic DNA. Leachate from the beads showed no increase in toxicity against human liver cells. This data demonstrates the efficacy of bismuth oxide-coated glass beads for controlling potentially dangerous cyanobacterial populations, whilst potentially reducing the amount of free-floating genomic DNA(an essential issue in the face of antimicrobial resistance) – all of which should be essential considerations in emerging water treatment technologies.

关键词： Photocatalysis Bismuth oxide Cyanobacteria Water treatment Antimicrobial

Determination of Variance of Secondary metabolites in Lettuces Grown Under Different Light Sources by Flow Injection mass Spectrometric(FImS)Fingerprinting and ANOVA-PCA

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Journal of Analysis and Testing 2018年第4期2卷 312-321页

作者： Jianghao Sun mengliang Zhang Nicola Kubzdela Yaguang Luo james m.Harnly Pei Chen US Department of Agriculture Agricultural Research ServiceBeltsville Human Nutrition Research CenterFood Composition and Methods Development LaboratoryBeltsvilleMD 20705USA Department of Chemistry Middle Tennessee State UniversityMurfreesboroTN 37132USA US Department of Agriculture Agricultural Research ServiceFood Quality Lab/Environmental Microbial and Food Safety LabBeltsvilleMD 20705USA

Lettuce(Lactuca sativa L.)is one of the most consumed vegetables in the world and different management practice can result in considerable variability of the secondary *** injection mass spectrometry(FImS)combined with analysis of variance-principle component analysis(ANOVA-PCA)was used to study differences in the secondary metabolites originat-ing from different lighting conditions(Sunlight,white light,and florescent light)and lettuce varieties(Romaine and Lollo Rossa).Ultra-high-performance liquid chromatography-high-resolution accurate mass spectrometry was used for putative marker compound *** acid,caffeic acid,chlorogenic acid,L-chicoric acid,and quercetin malonyl gluco-side varied significantly for Romaine lettuce grown under different light *** study showed that the combination of FImS fingerprinting and ANOVA-PCA can be a useful tool for the characterization of the sources of variance in plant materials regarding to genetic,environmental,and management factors.

关键词： Lettuce Lactuca sativa L. Flow injection mass spectrometric fingerprinting ANOVA-PCA