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journal of Earth Science 2018年第2期29卷 245-254页

作者： Wei Du Li Li donald j.weidner State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Mineral Physics Institute Department of Geosciences University of New York at Stony Brook

Partial melting experiments were carried on KLB-1 peridotite, a xenolith sample from the Earth＇s upper mantle, at 1.5 GPa and temperatures from 1 300 to 1 600 ℃, with heating time varies from 1 to 30 min. We quantify the axial temperature gradient in the deformation-DIA appa- ratus （D-DIA） and constrain the time scale of partial melting by comparing experimental observa- tions with calculated result from pMELTS program. The compositions of the liquid phase and the coexisting solid phases （clinopyroxene, orthopyroxene, and olivine） agree well with those calculated from pMELTS program, suggesting that local chemical equilibrium achieves during partial melting, although longer heating time is required to homogenize the bulk sample. The Mg# （=Mg/（Mg＋Fe） moi.%） of olivines from the 1-minute heating experiment changed continuously along the axial of the graphite capsule. A thermal gradient of 50 ℃/mm was calculated by comparing the Mg# of oli- vine grains with the output of pMELTS program. Olivine grains at the hot end of the graphite cap- sule from the three experiments heated at 1 400 ℃ but with different annealing time show consis- tence on Mg#, indicating that partitioning of Fe2＋ between the olivine grains and the silicate melt happened fast, and partial melting occurs in seconds.

关键词： peridotite partial melting temperature gradient pMELTS program.

Density measurements of molten minerals at high pressure using synchrotron x-ray radiography

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Density measurements of molten minerals at high pressure usi...

Elastic and Rheological Property Measurements at High Pressure and Temperature Using Ultrasonic Data Transfer Function Method

18th International Conference on High Pressure Science and Technology

作者： jiuHua Chen donald j.weidner Michael T.Vaughan Center for High Pressure Research and Department of Geosciences State University of New York at Stony BrookStony BrookNY 11794-2100 USA Center for High Pressure Research and Department of Geosciences State University of New York at Stony BrookStony BrookNY 11794-2100 USA Center for High Pressure Research and Department of Geosciences State University of New York at Stony BrookStony BrookNY 11794-2100 USA

＜正＞ Density of minerals is one of the key parametersfor earth modeling. While density measurements ofcrystalline mincrals at high pressure and temperaturecan be routinely carried out using in-situ diffractiontechniques, experiments to determine density of meltsat static high pressure are rare. Experimentaltechnique has hindered us from studying equation ofstate （EOS） of molten minerals, which is essential forunderstanding earth especially earth’s core. Effortshave been made to measure the density ofnon-crystalline materials under high pressure andtemperature by x-ray absorption [1, 2]. Howeverthis technique requires scanning across a spherical orcylindrical sample, and therefore the sample needs to

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Elastic and Rheological Property Measurements at High Pressu...

Ab Initio Molecular Dynamic Simulation on the Elasticity of Mg_3Al_2Si_3O_(12) Pyrope

18th International Conference on High Pressure Science and Technology

作者： Baosheng Li jennifer Kung Robert C.Liebermann donald j.weidner Mineral Physics Institute State University of New York at Stony Brook Stony Brook NY 11794 USA Mineral Physics Institute State University of New York at Stony Brook Stony Brook NY 11794 USA Mineral Physics Institute State University of New York at Stony Brook Stony Brook NY 11794 USA Mineral Physics Institute State University of New York at Stony Brook Stony Brook NY 11794 USA

＜正＞ Elastic and rheological properties of Earth minerals at high pressure and temperature are crucial for the understanding of the composition, structure and the dynamics of the Earth’s interior. Recently, we have developed the techniques to measure sound velocity to 8GPa and 1500K using ultrasonic interferemetry and in-situ synchrotron X-ray diffraction in a DIA-type, cubic anvil high pressure apparatus （SAM85） installed at beamline X17B at NSLS in Brookhaven National Laboratory. In these experiments, a piezoelectric transducer is mounted onto a non-stressed surface at the back of the WC anvil to transmit and receive acoustic signals from buffer rod and sample enclosed in Boron epoxy pressure medium. Conventional methods, such as pulse echo overlap and phase comparison, involve sending rf pulse as input signals and recording the in-phase and out-of-phase interference between the buffer rod and sample echoes for travel time measurements. In this case, data collection over a frequency range of 30 MHz takes several minutes which is not satisfactory for capturing the information related to the time dependent processes, such as strain relaxation at high pressure and temperature and phase transformations. In this study, we have implemented a new ultrasonic method for travel time measurements by recording the data transfer function in a a few seconds. Instead of rf pulse, a waveform of sine function （sin（x）/x） with a center frequency of the transducer resonance frequency is sent to excite the piezoelectric transducer. Figure la is an input sine signal with center frequency 50 MHz from 25 to 75 MHz. Its amplitude in the frequency domain is shown in Fig. Ib. The amplitude of the signal sent to the buffer rod and sample will be modulated by the transducer response in the corresponding frequency range. The data transfer function, i.e., the response from the buffer rod and sample along the wave propagation path is then recorded. Figure 2 is the recorded data transfe

关键词： Elasticity Synchrotron High Pressrue

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journal of Earth Science 2011年第2期22卷 169-175页

作者： Li Li donald j.weidner john Brodholt Dario Alfe G David Price Mineral Physics Institute Department of Geosciences University of New York at Stony Brook Stony Brook NY 11790 USA Department of Earth Sciences University College London Gower Street London WC1E6BT UK

We calculated thermo-elastic properties of pyrope（Mg3Al2Si3O12） at mantle pressures and temperatures using Ab initio molecular dynamic simulation.A third-order Birch-Murnaghan equation at a reference temperature of 2 000 K fits the calculations with bulk modulus,K0=159.5 GPa,K0＇=4.3,V0=785.89 A3,Grüneisen parameter,γ0=1.15,q=0.80,Anderson Grüneisen parameter δT=3.76 and thermal expansion,α0=2.93×10^-5 K^-*** to room temperature,where V0=750.80 A3,γ0 and α0 become 1.11 and 2.47×10^-5 K^-*** elastic properties of pyrope are found to be nearly isotropic at transition zone conditions.

关键词： AIMD thermo-elasticity pyrope high pressure.

Metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar M.Patel Oseeyi I.Daudu donald F.Becker jonathan L.Robinson jens Nielsen Department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

Composition and Equation of State of the Lower Mantle from the p VT Data of Perovskite

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矿物学报 2007年第Z1期27卷 82-83页

作者： Hui Zhao D.j.weidner Yun Liu Institute of Geochemistry Chinese Academy of SciencesGZ 550002China Dept.of Geoscienees SUNY at Stony BrookStony BrookNY 11790USA Dept.of Geoscienees SUNY at Stony BrookStony BrookNY 11790USA Institute of Geochemistry Chinese Academy of SciencesGZ 550002China

　　For the earth's lower mantle, a long-standing issue is whether it has a composition similar to that of the upper mantle represented by Ringwood's py-rolite model. Although a homogeneous mantle issupported by geophysical studies, and also used as an apriori assumption to estimate the composition of the bulk silicate earth (BSE) or primitive mantle( PM), it is inconsistent with a number of geochemi-cal observations.……

关键词： Lower Mantle upper mantle lower mantle the earth

Storylines of family medicine Ⅴ:ways of thinking—honing the therapeutic self

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Family Medicine and Community Health 2024年第S3期12卷 43-51页

作者： William B Ventres Leslie A Stone johanna F Shapiro Cynthia Haq jéssica R B Leao donald E Nease jr Liz Grant Stewart W Mercer john C M Gillies Pablo González Blasco Maria Auxiliadora C De Benedetto Graziela Moreto Marcelo R Levites jennifer E DeVoe William R Phillips jane M Uygur Thomas R Egnew Colette S Stanley Family and Preventive Medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA Family Medicine University of California Irvine School of MedicineIrvineCaliforniaUSA Faculty of Medicine University of Sao PauloSao PauloBrazil Family Medicine University of Colorado Anschutz Medical Campus School of MedicineAuroraColoradoUSA Usher Institute Edinburgh Medical SchoolUniversity of EdinburghEdinburghUK SOBRAMFA-Medical Education and Humanism Sao PauloBrazil Family Medicine Oregon Health&Science University School of MedicinePortlandOregonUSA Family Medicine University of Washington School of MedicineSeattleWashingtonUSA General Practice Royal College of Surgeons in IrelandDublinIreland General Internal Medicine Geriatrics&Palliative MedicineTulane University School of MedicineNew OrleansLouisianaUSA

Storylines of Family Medicine is a 12-part series of thematically linked essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅴ:ways of thinking—honing the therapeutic self’,authors present the following sections:‘Reflective practice in action’,‘The doctor as drug—Balint groups’,‘Cultivating compassion’,‘Towards a humanistic approach to doctoring’,‘Intimacy in family medicine’,‘The many faces of suffering’,‘Transcending suffering’and‘The power of listening to stories.’May readers feel a deeper sense of their own therapeutic agency by reflecting on these essays.

关键词： illustration dimensions suffering

Src Is Dephosphorylated at Tyrosine 530 in Human Colon Carcinomas

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Chinese journal of Cancer Research 2011年第3期23卷 229-231页

作者： jeffrey D Bjorge donald j Fujita Department of Biochemistry and Molecular Biology and Southern Alberta Cancer Research InstituteUniversity of Calgary

Objective：Src is a protein tyrosine kinase that plays important roles in cancer development,and Src kinase activity has been found to be elevated in several types of ***,the cause of the elevation of Src kinase activity in the majority of human colon carcinomas is still largely *** aim at finding the cause of elevated Src kinase activity in human colon ***：We employed normal colon epithelial FHC cells and examined Src activation in human colon carcinoma specimens from 8 *** expression levels were determined by Western blotting,and the activity of Src kinase by kinase ***：Actin levels were different between tumor and normal tissues,demonstrating the complexities and inhomogeneities of the tissue *** kinase activities were increased in the majority of the colon carcinomas as compared with normal colon epithelial cells （range 13-29）.Src protein levels were reduced in the colon *** Y530 phosphorylation levels were reduced to a higher extent than protein levels in the ***：The results suggest that Src specific activities were highly increased in human colon carcinomas;phosphorylation at Src Y530 was reduced,contributing to the highly elevated Src specific activity and Src kinase activity.

关键词： Src Kinase activation Dephosphorylation Colon carcinoma

Effect of particle stress tensor in simulations of dense gas-particle flows in fluidized beds

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Particuology 2018年第3期16卷 31-43页

作者： Mohammad Reza Haghgoo donald j. Bergstrom Raymond j. Spiteri Department of Mechanical Engineering University of Saskatchewan Saskatoon SK SFN 5A9 Canada Department of Computer Science University of Saskatchewan Saskatoon. SK S7N 5C9 Canada

A two-fluid model based on the kinetic theory of granular flow for the rapid-flow regime and the Coulomb friction law for the quasi-static regime is applied to predict the hydrodynamics of dense gas-particle flow in a three-dimensional fluidized bed. Two different models for the particle stress tensor that use different constitutive equations in the elastic-inertial regime are examined to assess their ability to predict bed dynamics. To understand how particle stress models affect structural features of the flow, a quantitative analysis is performed on some important aspects of the mechanics of bubbling beds that have received relatively little attention in the literature. Accordingly, different flow regimes are identified in the context of fluidized beds through the dimensionless inertial number, and the main characteristics of each regime are discussed. In addition, how the particle stress tensor manifests itself in the bubble characteristics, natural frequency of the bed, and particle Reynolds stress are investigated, all of which help to better understand the complex dynamics of the fluidized bed. The numerical results are validated against pub- lished experimental data and demonstrate the significant role of the stress tensor in the elastic-inertial regime.

关键词： Two-fluid model Inertial number Fluidized bed Flow regime Particle Reynolds stress MFIX

Bioacoustic variation of swimbladder disturbance sounds in Neotropical doradoid catfishes （Siluriformes： Doradidae, Auchenipteridae）： Potential morphological correlates

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Current Zoology 2012年第1期58卷 171-188页

作者： Kaatz, Ingrid M. Stewart, donald j. Department of Environmental and Forest Biology SUNY College of Environmental Science and Forestry Syracuse NY 13210 USA

Swimbladder disturbance sounds of doradoid catfishes （Doradidae and Aucheniptefidae） demonstrated striking waveform and spectrographic variation. We surveyed sounds of 25 doradoid species in 20 genera comparing these to sounds of four vocal outgroup catfish families. Sounds were either continuous waveforms （lacking interpulses） or pulsed （groups of pulses repeated at fixed temporal intervals）. This is the first evidence for swimbladder calls with fixed interpulse patterns in catfishes. Vocal mechanism components that were similar between doradids and auchenipterids included： swimbladder shape, swimbladder dimensions and sonic muscle-somatic index. Morphological traits that showed variation among taxa and were evaluated for po- tential correlates of call diversity are： 1） diverticula （marginal outpocketings of the swimbladder with no connection to inner ear） and 2） elastic spring apparatus Mtillerian rami （ESA-Mr）. Within the doradid subfamilies and within the Auchenipteridae most species differed significantly in dominant frequency with frequency ranges overlapping to some extent for most. Doradid swim- bladder diverticula did not explain dominant frequency variation within the doradoid superfamily. Some doradids with conical ESA-Mr had the highest dominant frequency sounds. Auchenipterids included both relatively lower and higher dominant fre- quency sound producers but lacked diverticula and had discoidal ESA-Mr. Comparing a phylogeny of doradoid genera with out- group taxa, we infer that complex diverticula and conical ESA-Mr are derived characters within the Doradidae. Species repre- senting outgroup families produced either continuous lower dominant frequency sounds （aspredinids, mochokids and pseudopimelodids） or pulsed higher dominant frequency sounds （pimelodids） [Current Zoology 58 （1）： 171-188, 2012].

关键词： Catfishes Communication Signal evolution Vocal mechanisms