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Innovative boron nitride-doped propellants

Defence Technology（防务技术） 2016年第2期12卷 69-80页

作者： Thelma MANNING richard FIELD Kenneth KLINGAMAN Michael FAIR John BOLOGNINI Robin CROWNOVER Carlton P.ADAM Viral PANCHAL Eugene ROZUMOV henry GRAU Paul MATTER Michael BEACHY Christopher HOLT samuel sOPOK UsA rmy RDECOM ARDEC Picatinny Arsenal NJ USA pH Matter LLC Columbus OH USA Benet Laboratory Watervliet NY USA

The U.s. military has a need for more powerful propellants with balanced/stoichiometric amounts of fuel and oxidants. However, balanced and more powerful propellants lead to accelerated gun barrel erosion and markedly shortened useful barrel life. Boron nitride(BN) is an interesting potential additive for propellants that could reduce gun wear effects in advanced propellants(Us patent pending 2015-026P). Hexagonal boron nitride is a good lubricant that can provide wear resistance and lower flame temperatures for gun barrels. Further, boron can dope steel, which drastically improves its strength and wear resistance, and can block the formation of softer carbides. A scalable synthesis method for producing boron nitride nano-particles that can be readily dispersed into propellants has been developed. Even dispersion of the nano-particles in a double-base propellant has been demonstrated using a solvent-based processing approach. stability of a composite propellant with the BN additive was verified. In this paper, results from propellant testing of boron nitride nano-composite propellants are presented, including closed bomb and wear and erosion testing. Detailed characterization of the erosion tester substrates before and after firing was obtained by electron microscopy,inductively coupled plasma and x-ray photoelectron spectroscopy. This promising boron nitride additive shows the ability to improve gun wear and erosion resistance without any destabilizing effects to the propellant. Potential applications could include less erosive propellants in propellant ammunition for large, medium and small diameter fire arms.

关键词：复合推进剂六角氮化硼硼掺杂创新型 X射线光电子能谱仪电感耦合等离子体腐蚀测试仪合成方法

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Myalgia may not be associated with severity of coronavirus disease 2019 (COVID-19)

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World Journal of Emergency Medicine 2020年第3期11卷 193-194页

作者： Giuseppe Lippi Johnny Wong Brandon Michael henry section of Clinical Biochemistry Department of NeuroscienceBiomedicine and MovementUniversity of VeronaVeronaItaly College of Medicine SUNY Downstate Health Sciences UniversityNew YorkUSA Cardiac Intensive Care Unit The Heart InstituteCincinnati Children’s Hospital Medical CenterOhioUSA

Dear editor,A recent study based on the use of experimental artificial intelligence(AI)tool showed 70%–80%accuracy in predicting development of severe disease in coronavirus disease 2019(COVID-19)based on predictive parameters alanine aminotransferase(ALT),myalgia and hemoglobin,whilst only 5 of 53 patients developed acute respiratory distress syndrome(ARDs),2 of whom reporting myalgia.

关键词： distress severity acute

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Gating system Design for a Magnesium Alloy Casting

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Journal of Materials science & Technology 2008年第1期24卷 93-95页

作者： Zhizhong sUN henry HU Xiang CHEN Qigui WANG Wenying YANG Department of Mechanical Automotive ＆ Materials Engineering University of Windsor Windsor Ontario Canada N9B 3P4 Canada Department of Electrical ＆： Computer Engineering University of Windsor Windsor Ontario Canada N9B 3P4 Canada General Motors Corporation Pontiac MI 48340 USA

The gating system of a cylindrical magnesium casting has been designed by using multiple objective optimiza- tion and Taguchi *** filling and solidification processes were simulated by using MAGMAsOFT（？）. The simulation results indicate that the gating system design has a significant effect on the quality of magne- sium *** an effort to obtain the optimal design of gating system,the signal-to-noise （s/N） ratio was used to analyze the effect of various gating designs on cavity filling and casting quality by using a weighting method based on the design of an orthogonal *** gating system parameters,namely,ingate height, ingate width,runner height,runner width,were optimized with a consideration of multiple objective criteria including filling velocity,shrinkage porosity and product yield.

关键词： Gating system Magnesium casting Optimization Taguchi method

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simulation and Visualisation of Functional Landscapes:Effects of the Water Resource Competition Between Plants

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Journal of Computer science & Technology 2007年第6期22卷 835-845页

作者： Vincent Le Chevalier Marc Jaeger 梅兴 Paul-henry Cournède Ecole Centrale Paris Laboratory of Applied Mathematics and systems Grande Voie des Vignes 92295 Chatenay-MalabryFrance INRIA Futurs DigiPlante TeamCIRAD AMAPTA A-51/PS2 34398 Montpellier Cedex 5France sino-French Laboratory LIAMA Institute of AutomationChinese Academy of Sciences

Vegetation ecosystem simulation and visualisation are challenging topics involving multidisciplinary aspects. In this paper, we present a new generic frame for the simulation of natural phenomena through manageable and interacting models. It focuses on the functional growth of large vegetal ecosystems, showing coherence for scales ranging from the individual plant to communities and with a particular attention to the effects of water resource competition between plants. The proposed approach is based on a model of plant growth in interaction with the environmental conditions. These are deduced from the climatic data （light, temperature, rainfall） and a model of soil hydrological budget. A set of layers is used to store the water resources and to build the interfaces between the environmental data and landscape components： temperature, rain, light, altitude, lakes, plant positions, biomass, cycles, etc. At the plant level, the simulation is performed for each individual by a structural-functional growth model, interacting with the plant＇s environment. Temperature is spatialised, changing according to altitude, and thus locally controls plant growth speed. The competition for water is based on a soil hydrological model taking into account rainfalls, water runoff, absorption, diffusion, percolation in soil. so far, the incoming light radiation is not studied in detail and is supposed constant. However, competition for light between plants is directly taken into account in the plant growth model. In our implementation, we propose a simple architecture for such a simulator and a simulation scheme to synchronise the water resource updating （on a temporal basis） and the plant growth cycles （determined by the sum of daily temperatures）. The visualisation techniques are based on sets of layers, allowing both morphological and functional landscape views and providing interesting tools for ecosystem management. The implementation of the proposed frame leads to encouraging resu

关键词： landscape visualisation plant growth models natural phenomena simulation water cycle models

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Climatic Fluctuation of Marine Isotope stage 9: A Case study in the southern Margin of the Chinese Loess Plateau

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地球科学学刊:英文版 2023年第5期34卷 1556-1566页

作者： Tieniu Wu Antai Cheng henry Lin Hailin Zhang Yi Jie Key Laboratory for Geographical Process Analysis&simulation Hubei ProvinceCentral China Normal UniversityWuhan 430079China Department of Ecosystem science and Management The Pennsylvania State UniversityUniversity ParkPA 16802U.S.A. College of Urban and Environmental sciences Central China Normal UniversityWuhan 430079China

Marine Isotope stages(MIs) 9 has been proposed as an analog for the present warm period. However, detailed studies of this geological time period are rare in loess-paleosol sequence. In the Chinese Loess Plateau(CLP), the corresponding stratum is the third paleosol layer(s3). Here, we report the terrestrial reconstruction of climatic fluctuations during MIs 9 by analyzing the paleo-climate indexes of s3 with high sampling density. Our results showed that:(1) During the period of MIs 9, the main climatic sub-cycle was 29 ka;(2) MIs 9 could be divided into five sections, MIs 9a, 9b, 9c, 9d, and 9e. Among them, MIs 9a, 9c, and 9e were warm stages, while MIs 9b and 9d were cool intervals;and 3) There were also three swift warm-wet events and one cool-dry event, which occurred around 332 –331, 324–323, 311–310, and 331–329 ka BP, respectively. The overall trend of paleo-climate fluctuation correlated approximately with sPECMAP, LR04 stack and Iberian margin deep-sea cores. This study suggested that the paleosol records in the southern margin of the CLP have global significance and contain more detailed climatic signals than marine deposits.

关键词： MIs 9 climatic fluctuation Paleosol s3 Chinese Loess Plateau environmental geology

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The transcriptomic signature of responses to larval crowding in Drosophila melanogaster

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Insect science 2023年第2期30卷 539-554页

作者： Juliano Morimoto Marius Wenzel Davina Derous Youn henry Herve Colinet school of Biological sciences University of AberdeenAberdeenUnited Kingdom Programa de Pos-graduacao em Ecologia e Conservacao Universidade Federal do ParanaCuritibaBrazil Institute of Mathematics King's CollegeUniversity of AberdeenAberdeenUnited Kingdom CNRs ECOBIO(Ecosystemesbiodiversiteévolution)—UMR 6553University of RennesRennesFrance Department of Ecology and Evolution University of LausanneLausanneSwitzerland

Intraspecific competition at the larval stage is an important ecological factor affecting life-history,adaptation and evolutionary trajectory in holometabolous ***,the molecular pathways underpinning these ecological processes are poorly *** reared Drosophila melanogaster at three egg densities(5,60,and 300 eggs/mL)and sequenced the transcriptomes of pooled third-instar *** also examined emergence time,egg-to-adult viability,adult mass,and adult sex-ratio at each *** crowding had minor detrimental effects on adult phenotypes compared to low density and yielded 24 differentially expressed genes(DEGs),including several chitinase *** contrast,high crowding had substantial detrimental effects on adult phenotypes and yielded 2107 *** these,upregulated gene sets were enriched in sugar,steroid and amino acid metabolism as well as DNA replication pathways,whereas downregulated gene sets were enriched in ABC transporters,taurine,Toll/Imd signaling,and P450 xenobiotics metabolism ***,our findings show that larval crowding has a large consistent effect on several molecular pathways(i.e.,core responses)with few pathways displaying density-specific regulation(i.e.,idiosyncratic responses).This provides important insights into how holometabolous insects respond to intraspecific competition during development.

关键词： intraspecific competition larval crowding life-history trade-offs transcriptomics

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Parallel mRNA, proteomics and miRNA expression analysis in cell line models of the intestine

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World Journal of Gastroenterology 2017年第41期23卷 7369-7386页

作者： Finbarr O’sullivan Joanne Keenan sinead Aherne Fiona O’Neill Colin Clarke Michael henry Paula Meleady Laura Breen Niall Barron Martin Clynes Karina Horgan Padraig Doolan richard Murphy National Institute for Cellular Biotechnology Dublin City University National Institute for Bioprocessing Research & Training Alltech Dunboyne

AIM To identify mi RNA-regulated proteins differentially expressed between Caco2 and HT-29: two principal cell line models of the *** Exponentially growing Caco-2 and HT-29 cells were harvested and prepared for m RNA, mi RNA and proteomic profiling. m RNA microarray profiling analysis was carried out using the Affymetrix Gene Chip Human Gene 1.0 sT array. mi RNA microarray profiling analysis was carried out using the Affymetrix Genechip mi RNA 3.0 array. Quantitative Label-free LC-Ms/Ms proteomic analysis was performed using a Dionex Ultimate 3000 RsLCnano system coupled to a hybrid linear iontrap/Orbitrap mass spectrometer. Peptide identities were validated in Proteome Discoverer 2.1 and were subsequently imported into Progenesis QI software for further analysis. Hierarchical cluster analysis for all three parallel datasets(mi RNA, proteomics, m RNA) was conducted in the R software environment using the Euclidean distance measure and Ward's clustering algorithm. The prediction of mi RNA and oppositely correlated protein/m RNA interactions was performed using Target scan 6.1. GO biological process, molecular function and cellular component enrichment analysis was carried out for the DE mi RNA, protein and m RNA lists via the Pathway studio 11.3 Web interface using their Mammalian *** Differential expression(DE) profiling comparing the intestinal cell lines HT-29 and Caco-2 identified 1795 Genes, 168 Proteins and 160 mi RNAs as DE between the two cell lines. At the gene level, 1084 genes were upregulated and 711 were downregulated in the Caco-2 cell line relative to the HT-29 cell line. At the protein level, 57 proteins were found to be upregulated and 111 downregulated in the Caco-2 cell line relative to the HT-29 cell line. Finally, at the mi RNAs level, 104 were upregulated and 56 downregulated in the Caco-2 cell line relative to the HT-29 cell line. Gene ontology(GO) analysis of the DE m RNA identified cell adhesion, migration and ECM o

关键词： Caco-2 HT-29 Microarray Proteomics miRNA Targetscan Gene ontology

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Using machine learning and a data-driven approach to identify the small fatigue crack driving force in polycrystalline materials

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npj Computational Materials 2018年第1期4卷 363-372页

作者： Andrea Rovinelli Michael D.sangid henry Proudhon Wolfgang Ludwig school of Aeronautics and Astronautics Purdue University701W.Stadium AveWest LafayetteIN 47907USA MINEs ParisTech PSL Research UniversityMAT-Centre des matériauxCNRS UMR 7633BP 8791003 EvryFrance University of Lyon INSA LyonMATEISUMR 5510 CNRSF-69621 LYONFrance

The propagation of small cracks contributes to the majority of the fatigue lifetime for structural *** significant interest,criteria for the growth of small cracks,in terms of the direction and speed of crack advancement,have not yet been *** this work,a new approach to identify the microstructurally small fatigue crack driving force is *** network and machine learning techniques are utilized to identify relevant micromechanical and microstructural variables that influence the direction and rate of the fatigue crack propagation.A multimodal dataset,combining results from a high-resolution 4D experiment of a small crack propagating in situ within a polycrystalline aggregate and crystal plasticity simulations,is used to provide training *** relevant variables form the basis for analytical expressions thus representing the small crack driving force in terms of a direction and a rate *** ability of the proposed expressions to capture the observed experimental behavior is quantified and compared to the results directly from the Bayesian network and from fatigue metrics that are common in the *** indicate that the direction of small crack propagation can be reliably predicted using the proposed analytical model and compares more favorably than other fatigue metrics.

关键词： fatigue crack driving

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A preliminary application of dental cementum incremental analysis to determine the season-of-death of equids from the Xujiayao site,China

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science China Earth sciences 2017年第6期60卷 1183-1188页

作者： LI Jingshu ZHANG shuangQuan henry T. BUNN Akshay sARATHI GAO Xing Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China University of Chinese Academy of sciences Beijing 100049 China University of Wisconsin-Madison Department of Anthropology Madison WI53706 United States

seasonality study of Paleolithic archaeological faunal assemblages is important for reconstructing modes of animal death and ancient hominin strategies for prey acquisition. The dental cementum of animal teeth records the season of an individual animal in which it died, providing the necessary evidence for determining any patterns in season of death. This article presents the procedure and preliminary results of the application of cementum incremental analysis to equid teeth, which comprise the dominant component of the fauna from the Xujiayao site—an early Late Pleistocene archaeological site in China. Results show multi-seasonal use in both the upper and lower layers of this site. Furthermore, attention is given to the method's future application in seasonality studies at Paleolithic archaeological sites in China.

关键词： Cementum Analysis seasonality Paleolithic Xujiayao site Zooarchaeology

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Rapid climate change-induced collapse of hunter-gatherer societies in the lower Mississippi River valley between ca. 3300 and 2780 cal yr BP

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science China Earth sciences 2018年第2期61卷 178-189页

作者： tristram r.kidder edward r.henry lee j.arco Department of Anthropology Washington University in St. Louis St. Louis 63130 USA Geoarehaeology Laboratory Washington University in St. Louis St. Louis 63130 USA GAI Consultants Inc. Homestead PA 15120 USA Teaching and Experimental Center for Archaeology and Cultural Heritage Protection Henan University Kaifeng 475001 China

Hunter-gatherer communities in the American southeast reached an apogee of social and political complexity in the period between ca. 4200 and 3000 cal yr BP. In the lower Mississippi Valley(LMV) the Poverty Point culture defined this period of socio-political elaboration. However, following a significant period of climate change that led to exceptional flooding and a major reorganization of the course of the Mississippi River, this culture collapsed beginning ca. 3300–3200 cal yr BP and the LMV was abandoned for the subsequent 500 years. In this study, we use data from the Jaketown site in the Yazoo Basin of west-central Mississippi to refine the chronology of the climate event that caused the collapse of the Poverty Point culture. A large flood buried Poverty Point-era occupation deposits at Jaketown around 3310 cal yr BP. Lateral migration of the Mississippi River during flooding led to inundation of the Yazoo Basin and re-occupation of ancient river courses. A coarse sand stratum topped by a more than a meter-thick fining upward sediment package marks a crevasse deposit caused by a rupture of the natural levee at Jaketown. This levee breach was part of a larger pattern of erratic flooding throughout the LMV and is associated with major landscape evolution and the abandonment of Poverty Point sites within the valley. Early Woodland peoples re-colonized the crevasse surface after ca. 2780 cal yr BP. Following this event, the Jaketown site and the eastern Yazoo Basin witnessed a period of landscape stability that lasts to this day. These archaeological data demonstrate how climate change and natural disasters can lead to socio-political dissolution and reorganization even in relatively small-scale hunter-gatherer populations.

关键词： Rapid climate change Hunter-gatherers Flooding Mississippi River Valley Poverty Point Jaketown site

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