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Induction of CXC chemokines in human mesenchymal stem cells by stimulation with secreted frizzled-related proteins through non-canonical Wnt signaling

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World Journal of Stem Cells 2015年第11期7卷 1262-1273页

作者： David S Bischoff Jian-Hua Zhu Nalini S Makhijani dean t yamaguchi Research Service VA Greater Los Angeles Healthcare System Department of Medicine David Geffen School of Medicine at UCLA

AIM: to investigate the effect of secreted frizzledrelated proteins(s FRPs) on CXC chemokine expression in human mesenchymal stem cells(h MSCs).MEtHODS: CXC chemokines such as CXCL5 and CXCL8 are induced in h MSCs during differentiation with osteogenic differentiation medium(OGM) and may be involved in angiogenic stimulation during bone repair. h MSCs were treated with conditioned medium(CM) from L-cells expressing non-canonical Wnt5 a protein, or with control CM from wild type L-cells, or directly with s FRPs for up to 10 d in culture. m RNA expression levels of both CXCL5 and CXCL8 were quantitated by real-time reverse transcriptase-polymerase chain reaction and secreted protein levels of these proteins determined by ELISA. Dose-(0-500 ng/m L) and time-response curves were generated for treatment with s FRP1. Signal transduction pathways were explored by western blot analysis with pan- or phosphorylation-specific antibodies, through use of specific pathway inhibitors, and through use of si RNAs targeting specific frizzled receptors(Fzd)-2 and 5 or thereceptor tyrosine kinase-like orphan receptor-2(Ro R2) prior to treatment with s FRPs. RESULtS: CM from L-cells expressing Wnt5 a, a noncanonical Wnt, stimulated an increase in CXCL5 m RNA expression and protein secretion in comparison to control L-cell CM. s FRP1, which should inhibit both canonical and non-canonical Wnt signaling, surprisingly enhanced the expression of CXCL5 at 7 and 10 d. Dickkopf1, an inhibitor of canonical Wnt signaling prevented the s FRPstimulated induction of CXCL5 and actually inhibited basal levels of CXCL5 expression at 7 but not at 10 d post treatment. In addition, all four s FRPs isoforms induced CXCL8 expression in a dose- and time-dependent manner with maximum expression at 7 d with treatment at 150 ng/m L. the largest increases in CXCL5 expression were seen from stimulation with s FRP1 or s FRP2. Analysis of mitogen-activated protein kinase signaling pathways in the presence of OGM sh

关键词： CXC chemokines Mesenchymal stem cell Osteogenesis Differentiation Wnt signaling pathway Frizzled-related protein Frizzled receptors

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WJSC 6^(th) Anniversary Special Issues(2):Mesenchymal stem cells “Ins” and “Outs” of mesenchymal stem cell osteogenesis in regenerative medicine

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World Journal of Stem Cells 2014年第2期6卷 94-110页

作者： dean t yamaguchi Research Service Veteran Administration Greater Los Angeles Healthcare System and David Geffen School of Medicine at University of California at Los Angeles

Repair and regeneration of bone requires mesenchymal stem cells that by self-renewal,are able to generate a critical mass of cells with the ability to differentiate into osteoblasts that can produce bone protein matrix(osteoid)and enable its *** number of human mesenchymal stem cells(hMSCs)diminishes with age and ex vivo replication of hMSCs has limited *** propagating hMSCs under hypoxic conditions may maintain their ability to self-renew,the strategy of using human telomerase reverse transcriptase(htERt)to allow for hMSCs to prolong their replicative lifespan is an attractive means of ensuring a critical mass of cells with the potential to differentiate into various mesodermal structural tissues including ***,this strategy must be tempered by the oncogenic potential of tERt-transformed cells,or their ability to enhance already established cancers,the unknown differentiating potential of high population doubling hMSCs and the source of hMSCs(e.g.,bone marrow,adipose-derived,muscle-derived,umbilical cord blood,etc.)that may provide peculiarities to self-renewal,differentiation,and physiologic function that may differ from non-transformed native *** engineering approaches to use hMSCs to repair bone defects utilize the growth of hMSCs on three-dimensional scaffolds that can either be a base on which hMSCs can attach and grow or as a means of sequestering growth factors to assist in the chemoattraction and differentiation of native *** use of whole native extracellular matrix(ECM)produced by hMSCs,rather than individual ECM components,appear to be advantageous in not only being utilized as a three-dimensional attachment base but also in appropriate orientation of cells and their differentiation through the growth factors that native ECM harbor or in simulating growth factor *** origin of native ECM,whether from hMSCs from young or old individuals is a critical factor in"rejuvenating"hMSCs from older individuals

关键词： Mesenchymal stem cell telomerase reverse transcriptase Extracellular matrix Osteogenesis Regenerative medicine tissue engineering Proliferation Differentiation

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Effect of Laminar Cooling on Phase transformation Evolution in Hot Rolling Process

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Journal of Iron and Steel Research International 2010年第10期17卷 28-32,44页

作者： NING Lin-xin YANG Dai-jun J Lin t A dean Shougang technology Institute Shougang Group Beijing 100041 China Department of Mechanical and Manufacturing Engineering University of Birmingham Birmingham B15 2TT UK

the effect of temperature variation owing to the cooling pattern （CP） on the microstructural evolution was investigated by establishing a thermomechanical coupled FE （finite element） model. A set of constitutive equations of phase transformation was implanted into the commercial FE solver MARC through the user defined subroutine CR- PLAW, and the temperature field was calculated by another user defined subroutine FILM. the results show that the final mierostructure is completely bainite phase for CP one, 98% of bainite phase and 2% of ferrite phase for CP two, and 55% of bainite phase, 35% of pearlite phase and 10% of ferrite phase for CP three.

关键词： hot rolling laminar cooling system cooling pattern thermomechanical modelling microstructural evolution constitutive equation phase transformation

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Public Exposure to U.S. Commercial Nuclear Power Plants Induced Disasters

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International Journal of Disaster Risk Science 2015年第3期6卷 238-249页

作者： dean Kyne Department of Sociology and Anthropology The University of Texas Rio Grande Valley

this study explores the potential risks associated with the 65 U.S.-based commercial nuclear power plants and the distribution of those risks among the populations of both their respective host communities and of the communities located in outlying areas. First, it starts by examining the racial/ethnic composition of the host community populations, as well as the disparities in socioeconomic status that exist, if any, between the host communities and communities located in outlying ***, it utilizes two independent-sample t tests to identify any differences in the sociodemographic compositions of the two areas. third, it explores regional demographic trends by looking at the percent change in demographic variables in the host communities and communities located in outlying areas in 1990–2000 and2000–2010. Findings reveal that during the past two decades more people were exposed to the risks as population living in the host communities increased.

关键词： Exposure to nuclear power disasters Host communities Nuclear disasters U.S. commercial nuclear power plants

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Application of Kelvin Probe to Studies of Fusion Reactor Materials under Irradiation

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Plasma Science and technology 2005年第4期7卷 2982-2984页

作者：罗广南 K.yamaguchi t.terai M.Yamawaki Department of Quantum Engineering and Systems Science Graduate School of Engineering The University of Tokyo7-3-1 KongoBunkyo-kuTokyo 113-8656Japan Neutron Science Rearch Center Japan Atomic Energy Research Institute 2-4 ShirakataTokai-muraIbaraki319-1195Japan

Recently, the work function （WF） changes in metallic and ceramic materials to be potentially used in future fusion reactors have been examined by means of Kelvin probe （KP）, under He ion irradiation in high energy （MeV） and / or low energy （500 eV） ranges. the results of polycrystalline Ni samples indicate that the 1 MeV beam only induces decrease in the WF within the experimental fluence range; whereas the irradiation of 500 eV beam results in decrease in the WF firstly, then increase till saturation. A dual layer surface model is employed to explain the observed phenomena, together with computer simulation results by SRIM code. Charges buildup on the surface of lithium ceramics has been found to greatly influence the probe output, which can be explained qualitatively using a model concerning an induction electric field due to external field and free charges on the ceramic surface.

关键词： fusion reactor materials work function irradiation

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Hurricane disturbances, tree diversity, and succession in North Carolina Piedmont forests, USA

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Journal of Forestry Research 2019年第1期30卷 219-231页

作者： Weimin Xi Robert K.Peet Michael t.Lee dean L.Urban Department of Biology University of North Carolina at Chapel Hill Department of Biological and Health Sciences Texas A & M University-Kingsville the Nicholas School of the Environment Duke University

Windthrow plays a critical role in maintaining species diversity in temperate forests. Do large-scale strong wind events(i.e., tropical cyclones, including hurricanes,typhoons and severe cyclonic storms) increase tree diversity in severely damaged forest areas? Do hurricanes(tropical cyclones that occurs in the Atlantic Ocean and northeastern Pacific Ocean) lead to altered relative abundance of shade-tolerant and shade-intolerant species? Did historic hurricanes alter the succession trajectory of the damaged forests? We used nearly 70-year tree demographic data to assess the effects of two major hurricanes on woody species diversity in Piedmont forests, North Carolina, USA. Species richness(S) and Shannon–Wiener's diversity index(H') were used to evaluate the changes in tree diversity. the changes in composition were assessed with Nonmetric Multidimensional Scaling. the pre-hurricane successional phase can strongly influence both the damage severity and subsequent responses. Although there is often an immediate drop in diversity following a hurricane, understory tree diversity quickly increases to levels that exceed those prior to the disturbance. this leads to an increase in diversity in stands that were substantially damaged. Hurricanes significantly decrease the dominance of shade-intolerant canopy species while increasing preestablished, more shade-tolerant species. We conclude that large, and infrequent hurricanes help to maintain local tree diversity, but also accelerate the increase in dominance of understory species such as red maple and beech.

关键词： Wind disturbance tree species diversity Plant succession Disturbance-diversity relationship Piedmont forests

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Potential Oscillations of a Stainless Steel Electrode during Galvanostatic Polarization in a Mixed Solution of Sulfuric and Chromic Acids

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 134-139页

作者： K Ogura W Lou M Nakayama t Fukume(Department of Applied Chemistry, yamaguchi University, Ube 755, Japan Department of Applied Chemistry Yamaguchi University Ube 755 Japan

Potential oscillations of a stainless steel electrode galvanostatically anodized have been observed in amixture of chromic and sulfuric acids. the potential regularly oscillated between 1.6 V vs. SCE (lower) and 2.1V(upper) with a certain frequency. the potential values are affected neither by the composition of chromic and sulfu-ric acids nor by the magnitude of applied current density although the potential frequency is very sensitive to theseparameters. this phenomenon is interpreted in terms of the repeated formation and disappearance of the saturatedlayer of dichromate ions on the electrode surface. Such scheme is consistent with the in situ FtIR spectroscopicresult that the concentration of Cr2O ions on the electrode surface increased with time during the polarization atthe lower potential but the change in concenetion of Cr2O ions was negligible at the higher potential.

关键词： stainless steel electrode potential galvanostatic polarization

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the use of animal sensor data for predicting sheep metabolisable energy intake using machine learning

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Information Processing in Agriculture 2021年第4期8卷 494-504页

作者： Hari Suparwito dean t.thomas Kok Wai Wong Hong Xie Shri Rai Murdoch University MurdochWA 6150Australia CSIRO Agriculture and Food Private Bag 5WembleyWA 6913Australia

the use of sensors for monitoring livestock has opened up new possibilities for the management of livestock in extensive grazing *** work presented in this paper aimed to develop a model for predicting the metabolisable energy intake(MEI)of sheep by using temperature,pitch angle,roll angle,distance,speed,and grazing time data obtained directly from wearable sensors on the sheep.A Deep Belief Network(DBN)algorithm was used to predict MEI,which to our knowledge,has not been attempted *** results demonstrated that the DBN method could predict the MEI for sheep using sensor data *** mean square error(MSE)values of 4.46 and 20.65 have been achieved using the DBN model for training and testing datasets,*** also evaluated the influential sensor data variables,i.e.,distance and pitch angle,for predicting the *** study demonstrates that the application of machine learning techniques directly to on-animal sensor data presents a substantial opportunity to interpret biological interactions in grazing systems directly from sensor *** expect that further development and refinement of this technology will catalyse a step-change in extensive livestock management,as wearable sensors become widely used by livestock producers.

关键词： Energy intake Livestock behaviour Machine learning Predictions Sensor data

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A Longitudinal Study of Human Exposure to Potential Nuclear Power Plant Risk

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International Journal of Disaster Risk Science 2015年第4期6卷 399-414页

作者： dean Kyne Jason t.Harris Department of Sociology and Anthropology The University of Texas Rio Grande Valley School of Health Sciences Purdue University

this study constructs a potential risk index(PRI) for the 65 U.S.-based commercial nuclear power plant(NPP) sites in relation to their surrounding populations. Four risk levels are defined: low risk, moderate risk,high risk, and very high risk. Discrepancies that exist in the sociodemographic characteristics of the host communities’ populations are examined as sorted by risk-level *** is found that a greater percentage of minority groups are exposed to the highest levels of risk. In addition, percent 'Hispanic' and percent 'Other,'a grouping that includes multiracial, mixed, interracial, as well as Hispanic and Latino groups(for example, Mexican, Puerto Rican,Cuban, or Spanish) are categories that show the greatest percent change in both the period 1990–2000 and2000–2010.

关键词： Environmental justice Nuclear power induced disaster Nuclear power plant Potential risk index

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Microstructure and mechanical properties of curved AZ31 magnesium alloy profiles produced by differential velocity sideways extrusion

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Journal of Magnesium and Alloys 2023年第2期11卷 493-508页

作者： Wenbin Zhou Jianguo Lin trevor A.dean Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Mechanical Engineering University of BirminghamBirmingham B152TTUK School of Science and Engineering University of DundeeDundee DD14HNUK

Lightweight curved profiles are widely utilised in the transportation industry considering the increasing need for improving aerodynamic efficiency,aesthetics and cutting *** this paper,curved AZ31 Mg alloy profiles were manufactured in one operation by a novel process,differential velocity sideways extrusion(DVSE),in which two opposed rams were *** of extrusion temperature and velocity(strain rate) on curvature,microstructure,and mechanical properties of the formed profiles were *** curvature was found to be more readily controlled by the velocity ratio of the bottom ram v2to the top ram v1,whereas extrusion temperature(t=250,300,350℃)and extrusion velocity(v_(1)=0.1,1 mm/s) slightly affect curvature for a given velocity ratio.A homogeneous microstructure with equiaxed grains(~4.5 μm) resulted from dynamic recrystallisation(DRX),was observed after DVSE(v_(2)/v_(1)=1/2) at 300 ℃ and v_(1)=0.1 mm/s,where the initial billet had an average grain size of ~25 *** extrusion temperature leads to grain growth(~5 μm) at 350 ℃ and v_(1)=0.1 mm/*** is incomplete at the relatively low temperature of 250℃(v_(1)=0.1 mm/s),and higher strain rate with v1=1mm/s(t=300℃),resulting in inhomogeneous bi-modal necklace pattern grains ranging in size around 1-25 μm for the former and 2-20μm for the *** refinement is attributed to DRX during the severe plastic deformation(SPD) arising in DVSE,and initiates at the prior boundaries of coarse grains in a necklace-like *** with the billet,micro-hardness and ultimate tensile strength of the profiles have been enhanced,which is compatible with grain ***,an obvious increase in tensile ductility was ***,yield strength slightly decreases except for the complete DRXed case(300℃,v_(1)=0.1 mm/s),where a slightly higher value was found,indicating strengthening by grain refinement is greater than softening caused by texture *** initial billet had a strong b

关键词： Extrusion Magnesium alloy AZ31 Curved profiles/sections Bending Grain refinement Dynamic recrystallisation

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