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Osteopontin: a leading candidate adhesion molecule for implantation in pigs and sheep

Journal of Animal Science and Biotechnology 2015年第2期6卷 177-190页

作者： Greg A johnson Robert C Burghardt fuller W Bazer Department of Veterinary Integrative Biosciences Texas A&M UniversityCollege Station Department of Animal Science Texas A&M UniversityCollege Station

Osteopontin （OPN; also known as Secreted Phosphoprotein 1, SPP1） is a secreted extra-cellular matrix （ECM） protein that binds to a variety of cell surface integrins to stimulate cell-cell and cell-ECM adhesion and communication. It is generally accepted that OPN interacts with apically expressed integrin receptors on the uterine luminal epithelium （LE） and conceptus trophectoderm to attach the conceptus to the uterus for implantation. Research conducted with pigs and sheep has significantly advanced understanding of the role（s） of OPN during implantation through exploitation of the prolonged peri-implantation period of pregnancy when elongating conceptuses are free within the uterine lumen requiring extensive paracrine signaling between conceptus and endometrium. This is followed by a protracted and incremental attachment cascade of trophectoderm to uterine LE during implantation, and development of a true epitheliochorial or synepitheliochorial placenta exhibited by pigs and sheep, respectively. In pigs, implanting conceptuses secrete estrogens which induce the synthesis and secretion of OPN in adjacent uterine LE. OPN then binds to αvβ6 integrin receptors on trophectoderm, and the αvβ3 integrin receptors on uterine LE to bridge conceptus attachment to uterine LE for implantation. In sheep, implanting conceptuses secrete interferon tau that prolongs the lifespan of CL. Progesterone released by CL then induces OPN synthesis and secretion from the endometrial GE into the uterine lumen where OPN binds integrins expressed on trophectoderm （αvβ3） and uterine LE （identity of specific integrins unknown） to adhere the conceptus to the uterus for implantation. OPN binding to the αvβ3 integrin receptor on ovine trophectoderm cells induces in vitro focal adhesion assembly, a prerequisite for adhesion and migration of trophectoderm, through activation of： 1） P70S6K via crosstalk between fRAP1/MTOR and MAPK pathways; 2） MTOR, PI3K, MAPK3/MAPK1 （Erk1/2） and MAPK14 （p38） signalin

关键词： Implantation Integrins Psteoponti Pigs Sheep

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Evolutionary diversity as a catalyst for biological discovery

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Integrative Zoology 2018年第6期13卷 616-633页

作者： Zachary V.johnson Larry J.YOUNG School of Biological Sciences Georgia Institute of TechnologyAtlantaGeorgiaUSA Center for Translational Social Neuroscience Silvio O.Conte Center for Oxytocin and Social CognitionDepartment of Psychiatry and Behavioral SciencesYerkes National Primate Research CenterEmory UniversityAtlantaGeorgiaUSA

The tremendous diversity of animal behaviors has inspired generations of scientists from an array of biological *** complement investigations of ecological and evolutionary factors contributing to behavioral evolution,modern sequencing,gene editing,computational and neuroscience tools now provide a means to discover the proximate mechanisms upon which natural selection acts to generate behavioral *** behaviors are motivated behaviors that can differ tremendously between closely related species,suggesting phylogenetic plasticity in their underlying biological *** addition,convergent evolution has repeatedly given rise to similar forms of social behavior and mating systems in distantly related *** behavioral divergence and convergence provides an entry point for understanding the neurogenetic mechanisms contributing to behavioral *** argue that the greatest strides in discovering mechanisms contributing to social behavioral diversity will be achieved through integration of interdisciplinary comparative approaches with modern tools in diverse species *** review recent advances and future potential for discovering mechanisms underlying social behavioral variation;highlighting patterns of social behavioral evolution,oxytocin and vasopressin neuropeptide systems,genetic/transcriptional“toolkits,”modern experimental tools,and alternative species systems,with particular emphasis on Microtine rodents and Lake Malawi cichlid fishes.

关键词： cichlids oxytocin and vasopressin social behavior toolkits voles

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Characterisation, Luminescence and Antibacterial Properties of Stable AgNPs Synthesised from AgCl by Precipitation Method

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Journal of Materials Science & Technology 2015年第11期31卷 1125-1132页

作者： Arockiasamy Ajaypraveenkumar johnson Henry Kannusamy Mohanraj Ganesan Sivakumar Sankaran Umamaheswari Department of Physics Manonmaniam Sundaranar University Centralised Instrumentation and Service Laboratory Department of Physics Annamalai University Department of Biotechnology Manonmaniam Sundaranar University

Silver nanoparticles （AgNPs） were synthesised using equimolar concentrations of redtlcing agent vitamin C and AgCl precursor by simple precipitation method. The synthesised AgNPs were characterised by X-ray diffraction （XRD）, UV-Visible, photoluminescence and field emission scanning electron microscopy （fESEM） analysis. The formation of AgNPs was confirmed by the typical surface plasmon resonance band at 426 nm. The presence of elemental silver and pure crystalline face centre cubic （fcc） structure was confirmed by energy dispersive X-ray analysis and XRD analysis, respectively. The fESEM images showed the formation of spherical AgNPs for lower concentrations （0.1 and 0.3 mol/L） while spike and flower shaped particles were formed for higher concentration. Photoluminescence characteristic band was observed with no shift at 390 nm indicating the stable nature of AgNPs. The antibacterial property of the AgNPs was tested against gram negative bacteria Pseudomonas aeruginosa by using Cissus quadrangular as a control and the result showed that vitamin C reduced AgNPs have good antibacterial activity.

关键词： Silver nanoparticles Precipitation Rietveld refinement Photoluminescence spectroscopy Optical properties

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World Class Elite Breaststrokers Downward Kick EMG Muscle Activity of the Gluteus Maximus, Quadriceps femoris, Hamstring, Gastrocnemius Medialis, Rectus Abdominal, and Erector Spinae

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Psychology Research 2024年第2期14卷 64-69页

作者： Takahisa Ide William f.johnson Sadafumi Takise Noriko Inada Hiromasa fujimori Takeharu fujimori Emi Moronuki Ai Soma Kazuki Watanabe Asahi Nagahata Iryna Glavnyk Mark Nikolaev Bogdan Plavin Osaka University of Health and Sport Sciences OsakaJapan Grand Canyon University Phoenix Phoenix Swim Club Paradise ValleyUSA Texas A&M University Corpus Corpus ChristiUSA Miki House TokyoJapan Valparaiso University ValparaisoUSA

This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite *** compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick *** find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick *** increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant *** this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke.

关键词： swimming breaststroke downward kick EMG imagination world class elite swimmers

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Volcano video data characterized and classified using computer vision and machine learning algorithms

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Geoscience frontiers 2020年第5期11卷 1789-1803页

作者： Alex J.C.Witsil Jeffrey B.johnson Department of Geosciences Boise State UniversityBoiseIDUSA

Video cameras are common at volcano observatories,but their utility is often limited during periods of crisis due to the large data volume from continuous acquisition and time requirements for manual *** cameras to serve as effective monitoring tools,video frames must be synthesized into relevant time series signals and further analyzed to classify and characterize observable *** this study,we use computer vision and machine learning algorithms to identify periods of volcanic activity and quantify plume rise velocities from video *** were collected at Villarrica Volcano,Chile from two visible band cameras located^17 km from the vent that recorded at 0.1 and 30 frames per second between february and April *** these two months,Villarrica exhibited a diverse range of eruptive activity,including a paroxysmal eruption on 3 *** to and after the eruption,activity included nighttime incandescence,dark and light emissions,inactivity,and periods of cloud *** quantify the color and spatial extent of plume emissions using a blob detection algorithm,whose outputs are fed into a trained artificial neural network that categorizes the observable activity into five *** shifts from primarily nighttime incandescence to ash emissions following the 3 March paroxysm,which likely relates to the reemergence of the buried lava *** periods exhibiting plume emissions are further analyzed using a row and column projection algorithm that identifies plume onsets and calculates apparent plume horizontal and vertical rise *** onsets are episodic,occurring with an average period of^50 s and suggests a puffing style of degassing,which is commonly observed at ***,the lack of clear acoustic transients in the accompanying infrasound record suggests puffing may be controlled by atmospheric effects rather than a degassing regime at the *** presented here offer a generalized toolset for volcano monito

关键词： Volcano monitoring Plume exit velocity Volcano webcam Image processing Machine learning Villarrica

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THE EffECT Of MINE TAILINGS ON LEVELS Of HEAVY METALS IN SEAWATER

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Acta Oceanologica Sinica 1986年第3期5卷 401-415页

作者： C.S.WONG,f.A.WHITNEY,W.K.johnson,LU XIANKUN,WUJINPING,WUSHENGSAN,LIJINXIA Ocean Chemistry Division Institute of Ocean Sciences Sidney B.C. Canada Ocean Chemistry Division Institute of Ocean Sciences Sidney B.C. Canada Ocean Chemistry Division Institute of Ocean Sciences Sidney B.C. Canada Shandong College of Oceanology Qingdao China Third Institute of Oceanography State Oceanic Administration Xiamen China Third Institute of Oceanography State Oceanic Administration Xiamen China Third Institute of Oceanography State Oceanic Administration Xiamen China

Changes in levels of heavy metals in seawater resulting from the addition of mine tailings were studied using plastic enclosures. Nominal concentrations of 10 mg l-1 and 100 mg l-1 of mine tailings from a B. C. molybdenum mine were added, and the metal levels were followed together with sedimentation rates, particle size distribution and other oceanographic and biological time-series parameters over sixteen days. No substantial elevation in levels of zinc, cadmium and copper was observed in the tailing bags compared to that in a background control bag with no addition of tailings. Lead showed a substantial increase in seawater following tailing addition and its removal apparently was with detritus settling following a plankton bloom, and inorganic settling of fine tailing particles.

关键词： Pb THE EffECT Of MINE TAILINGS ON LEVELS Of HEAVY METALS IN SEAWATER Cd

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Mutual Authentication Protocols for RfID Systems

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International Journal of Automation and computing 2008年第4期5卷 348-365页

作者： Ashrar A.Omer johnson P.Thomas Department of Computer Science Oklahoma State University

With the availability of low-cost radio frequency identification (RfID) tags,security becomes an increasing concern. However,such tags do not permit complex cryptographic functions due to their computational,communications,and storage limitations. In this paper,we investigate the security issues and requirements of RfID systems,and propose ultra-light weight and light weight protocols for low-cost RfID *** proposed protocols has been applied to a supply chain management system.

关键词： Security mutual authentication supply chain management RfID Systems.

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Investigation of ductile iron casting process parameters using Taguchi approach and response surface methodology

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China foundry 2016年第5期13卷 352-360页

作者： A. johnson Santhosh A. R. Lakshmanan Dept of Mechanieal Engineering PPG Institute of Technology Coimbatore India Dept of Mechanical Engineering PSG College of Technology Coimbatore India

To find the optimized levels of various casting parameters in the ductile iron casting, various casting defects and the rejection rate were observed from a medium scale foundry. The controlled values of different casting parameters such as pouring temperature, inoculation, carbon equivalent, moisture content, green compression strength, permeability and mould hardness were selected. Three different melts of metal with 0.4wt.%, 0.6wt.%, and 0.8wt.% inoculation （fe-Si-Mg alloy and post inoculant） were produced using a 1-ton capacity coreless medium frequency induction furnace. L-27 orthogonal array with 3-level settings were chosen for the analysis. Responses for each run were observed. The signal-to-noise （S/N） ratio for each run was calculated using the Taguchi approach, and the optimized levels of different casting parameters were identified based on the SIN ratio. The analysis of variance for the casting acceptance percentage concludes that inoculation is the most significant factor affecting the castings＇ quality with a contribution percentage of 44%; an increase in inoculation results in a significant improvement in acceptance percentage of ductile iron castings. The experiment results showed that with the optimized parameters, the rejection rate was reduced from 16.98% to 6.07%.

关键词： optimized levels casting parameters S/N ratio Taguchi approach ANOVA ‘f’-Test

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Anti-bacterial studies on Hemigraphis colorata(Blume) *** and Elephantopus scaber L.

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Asian Pacific Journal of Tropical Medicine 2012年第1期5卷 52-57页

作者： Vimala Thankappan Anitha johnson Marimuthu Solomon Jeeva Centre for Biodiversity and Biotechnology Department of BotanyNesamony Memorial Christian CollegeMarthandam-629165Tamil NaduIndia Department of Plant Biology and Plant Biotechnology StXavier's College(Autonomous)Palayamkottai-627 002Tamil NaduIndia

Objective:To examine the ethanol,aqueous,chloroform,benzene,acetone and petroleum ether extracts of Hemigraphis colorata(***) leaves and stem and Elephantopus scaber (***) leaves,root and flower for the presence of phyto-constituents and screened the antibacterial activity against the selected ***:The fresh materials were shade dried and powdered using the tissue *** dried and powered materials(50 g) were extracted successively with 200 mL of aqueous,acetone,benzene,chloroform,*** petroleum ether by using Soxhlet extractor for 8 h at a temperature not exceeding the boiling point of the ***,acetone,benzene,chloroform,*** petroleum ether extracts were prepared from powdered materials were used for preliminary phytnehemical and antimicrobial studies using standard ***:The crude aqueous,acetone,benzene,chloroform, *** petroleum ether extracts *** leaves,flower and root and *** leaves and stem demonstrated that out of(5×6×12 = 360) tests for the presence or absence of the above compounds.188 tests gave positive results and the remaining 172 gave negative results. The results of the phvtochemical screening revealed that phenol(12/12).carbohydrates(9/12). steroids(8/12).saponins and coumarins(7/12).tannins(6/12),proteins(5/12).earboxylic acid and flavonoids(4/12).xanthoproteins(3/12) and alkaloids(2/12) presence in the crude aqueous, acetone,benzene,chloroform,*** petroleum ether extracts of *** leaves and *** crude aqueous,acetone,benzene,chloroform,*** petroleum ether extracts *** leaves,flower and root displayed the presence of phenol(18/18).tannin(17/18). carbohydrates(16/18).steroids(14/18),oarboxylic acid and coumarins(12/18).saponins(10/18), xanthoprotein(9/18).flavonoids(7/18).protein(4/18) and alkaloids(2/18).The root ethanolic extracts of *** illustrated the highest zone of inhibition against three pathogens viz.. Staphylococcus aure

关键词： Anti-bacterial Phytochemistry Sceondary metabolites

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Pressure-dependent phase transition of 2D layered silicon telluride(Si2le3)and manganese intercalated silicon telluride

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Nano Research 2019年第9期12卷 2373-2377页

作者： Virginia L. johnson Auddy Anilao Kristie J. Koski Department of Chemistry University of CaliforniaDavisDavisCA 95616USA

Two-dimensional(2D)layered silicon telluride(SizTes)nanocrystals were compressed to 12 GPa using diamond anvil cell *** measurements show a color change from transparent red to opaque black indicating a semiconductor-to-metal phase *** scattering was used to observe the stiffening of the crystal lattice and subsequent phase behavior.A possible phase transition was *** 9.5±0.5 GPa evidenced by the disappearance of the Atg stretching *** was intercalated with elemental manganese to^1 at.%.Intercalation lowers the pressure of the proposed phase transition to 7.5±1 *** modes show both phonon stiffening and phonon softening,suggesting negative linear *** results provide fundamental insight into the high-pressure optical phonon behavior of silicon telluride and illuminate how a specific electron-donating intercalant can chemically alter pressure-dependent optical phonon behavior.

关键词： silicon telluride Si2Te3 high pressure diamond anvil cell two-dimensional(2D)layered material

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