574 research outputs found
Evidance for an Oxygen Diffusion Model for the Electric Pulse Induced Resistance Change Effect in Oxides
Electric pulse induced resistance (EPIR) switching hysteresis loops for
Pr0.7Ca0.7MnO3 (PCMO) perovskite oxide films were found to exhibit an
additional sharp "shuttle peak" around the negative pulse maximum for films
deposited in an oxygen deficient ambient. The device resistance hysteresis loop
consists of stable high resistance and low resistance states, and transition
regions between them. The resistance relaxation of the "shuttle peak" and its
temperature behavior as well as the resistance relaxation in the transition
regions were studied, and indicate that the resistance switching relates to
oxygen diffusion with activation energy about 0.4eV. An oxygen diffusion model
with the oxygen ions (vacancies) as the active agent is proposed for the
non-volatile resistance switching effect in PCMO.Comment: 7 pages, 5 figure
High Azimuthal Asymmetry in Non-central A+A at RHIC
The high GeV azimuthal asymmetry, , in
non-central nuclear collisions at RHIC is shown to be a sensitive measure of
the initial parton density distribution of the produced quark-gluon plasma. A
generalization of the Gyulassy-Levai-Vitev (GLV) non-abelian energy loss
formalism including Bjorken 1+1D expansion as well as important kinematic
constraints is used.Comment: 4 pages, Revtex, bbox.sty, 4 eps figures, references added, minor
corrections, Phys.Rev.Lett versio
Estimating Mass of Sigma-Meson and Study on Application of the Linear Sigma-Model
Whether the () exists as a real particle is a
long-standing problem in both particle physics and nuclear physics. In this
work, we analyze the deuteron binding energy in the linear model and
by fitting the data, we are able to determine the range of and
also investigate applicability of the linear model for the interaction
between hadrons in the energy region of MeV's. Our result shows that the best
fit to the data of the deuteron binding energy and other experimental data
about deuteron advocates a narrow range for the meson mass as MeV and the concrete values depend on the input parameters
such as the couplings. Inversely fitting the experimental data, our results set
constraints on the couplings. The other relevant phenomenological parameters in
the model are simultaneously obtained.Comment: 12 page
Strangeness Enhancement in and Interactions at SPS Energies
The systematics of strangeness enhancement is calculated using the HIJING and
VENUS models and compared to recent data on , and
collisions at CERN/SPS energies (). The HIJING model is used to
perform a {\em linear} extrapolation from to . VENUS is used to
estimate the effects of final state cascading and possible non-conventional
production mechanisms. This comparison shows that the large enhancement of
strangeness observed in collisions, interpreted previously as possible
evidence for quark-gluon plasma formation, has its origins in non-equilibrium
dynamics of few nucleon systems. % Strangeness enhancement %is therefore traced
back to the change in the production dynamics %from to minimum bias
and central collisions. A factor of two enhancement of at
mid-rapidity is indicated by recent data, where on the average {\em one}
projectile nucleon interacts with only {\em two} target nucleons. There appears
to be another factor of two enhancement in the light ion reaction relative
to , when on the average only two projectile nucleons interact with two
target ones.Comment: 29 pages, 8 figures in uuencoded postscript fil
Hemorrhagic Fever with Renal Syndrome Complicated by Acute Pancreatitis, High Intraocular Pressure, and Pulmonary Involvement: a Case Report
Xinran Yang,1,* Chenglin Yu,2,* Yixin Chen,1 Bin Nian,3 Min Chai,1 Dilimulat Maimaiti,4 Dahai Xu,1 Xiuxian Zang1 1Department of Emergency Medicine, The First Hospital of Jilin University, Changchun, Jilin, 130000, People’s Republic of China; 2Department of Emergency Medicine, Yanbian University Hospital, Yanji, Jilin, 133000, People’s Republic of China; 3Department of Ultrasonography, Yanbian University Hospital, Yanji, Jilin, 133000, People’s Republic of China; 4Department of Emergency Medicine, Seventh Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, 830054, People’s Republic of China*These authors contributed equally to this workCorrespondence: Dahai Xu; Xiuxian Zang, Department of Emergency Medicine, The First Hospital of Jilin University, No. 1 Xinmin Street, Chaoyang District, Changchun, Jilin, 130000, People’s Republic of China, Tel +86-15043032548 ; +86-13596097922, Email [email protected]; [email protected]: Hemorrhagic fever with renal syndrome (HFRS), a naturally occurring epidemic disease, is primarily caused by hantaviruses. It frequently involves the lungs and is characterized by symptoms such as fever, hemorrhage, and renal failure. However, the occurrence of acute pancreatitis (AP) in HFRS patients can be neglected, and high intraocular pressure (IOP) is exceedingly uncommon. In this report, we discuss the case of a 30-year-old male who presented with fever, nausea, vomiting, and abdominal pain. Physical examination revealed extremity petechiae rashes and elevated IOP. Laboratory tests indicated coagulopathy and renal failure. A computed tomography scan confirmed AP. Further testing revealed a positive anti-hantavirus IgM antibody. The patient received supportive care, fluid hydration, hemofiltration, mannitol, brinzolamide, and brimonidine to reduce IOP. Three days post-admission, the patient developed shortness of breath and chest pain. Subsequent chest computed tomography revealed pulmonary edema and bilateral pleural effusion. Treatment included oxygen supply, respiratory support, and thoracentesis, with continued hemofiltration. The patient recovered, regaining normal pulmonary and renal functions and normalized IOP. This case underscores the importance of comprehensive evaluations and vigilant monitoring in HFRS patients, particularly measuring IOP in those with visual complaints, to save lives and reduce morbidity.Keywords: hemorrhagic fever with renal syndrome, acute pancreatitis, high intraocular pressure, pulmonary edem
Reaction Operator Approach to Multiple Elastic Scatterings
We apply the GLV Reaction Operator formalism to compute the effects of
multiple elastic scatterings of jets propagating through dense matter. We
derive the elastic Reaction Operator and demonstrate that the recursion
relations have a closed form solution that reduces to the familiar Glauber
form. We also investigate the accuracy of the Gaussian dipole approximation for
jet transverse momentum broadening.Comment: 9 pages, 4 .ps figures. Uses REVTeX and bbox.st
Characterizing temporary hydrological regimes at a European scale
Monthly duration curves have been constructed from climate data across Europe to help address the relative frequency of ecologically critical low flow stages in temporary rivers, when flow persists only in disconnected pools in the river bed. The hydrological model is 5 based on a partitioning of precipitation to estimate water available for evapotranspiration and plant growth and for residual runoff. The duration curve for monthly flows has then been analysed to give an estimate of bankfull flow based on recurrence interval. The corresponding frequency for pools is then based on the ratio of bank full discharge to pool flow, arguing from observed ratios of cross-sectional areas at flood 10 and low flows to estimate pool flow as 0.1% of bankfull flow, and so estimate the frequency of the pool conditions that constrain survival of river-dwelling arthropods and fish. The methodology has been applied across Europe at 15 km resolution, and can equally be applied under future climatic scenarios
Evolutionary continuous cellular automaton for the simulation of wet etching of quartz
Anisotropic wet chemical etching of quartz is a bulk micromachining process for the fabrication of micro-electro-mechanical systems (MEMS), such as resonators and temperature sensors. Despite the success of the continuous cellular automaton for the simulation of wet etching of silicon, the simulation of the same process for quartz has received little attention-especially from an atomistic perspective-resulting in a lack of accurate modeling tools. This paper analyzes the crystallographic structure of the main surface orientations of quartz and proposes a novel classification of the surface atoms as well as an evolutionary algorithm to determine suitable values for the corresponding atomistic removal rates. Not only does the presented evolutionary continuous cellular automaton reproduce the correct macroscopic etch rate distribution for quartz hemispheres, but it is also capable of performing fast and accurate 3D simulations of MEMS structures. This is shown by several comparisons between simulated and experimental results and, in particular, by a detailed, quantitative comparison for an extensive collection of trench profiles. © 2012 IOP Publishing Ltd.We are grateful to D Cheng and K Sato (Nagoya University, Japan) for providing part of the experimental data. We acknowledge support by the JAE-Doc grant form the Junta para la Ampliacion de Estudios program co-funded by FSE, the Ramon y Cajal Fellowship Program by the Spanish Ministry of Science and Innovation, NANO-IKER Project (IE11-304) from the ETORTEK program by the Basque Government and the Professor Partnership Program by NVIDIA Corporation.Ferrando Jódar, N.; Gosalvez Ayuso, MA.; Colom Palero, RJ. (2012). Evolutionary continuous cellular automaton for the simulation of wet etching of quartz. Journal of Micromechanics and Microengineering. 22(2). https://doi.org/10.1088/0960-1317/22/2/025021S222Hida, H., Shikida, M., Fukuzawa, K., Murakami, S., Sato, K., Asaumi, K., … Sato, K. (2008). Fabrication of a quartz tuning-fork probe with a sharp tip for AFM systems. Sensors and Actuators A: Physical, 148(1), 311-318. doi:10.1016/j.sna.2008.08.021Oh, H., Kim, G., Seo, H., Song, Y., Lee, K., & Yang, S. S. (2010). Fabrication of micro-lens array using quartz wet etching and polymer. Sensors and Actuators A: Physical, 164(1-2), 161-167. doi:10.1016/j.sna.2010.10.003Xing, Y., Gosálvez, M. A., & Sato, K. (2007). Step flow-based cellular automaton for the simulation of anisotropic etching of complex MEMS structures. New Journal of Physics, 9(12), 436-436. doi:10.1088/1367-2630/9/12/436Zhou, Z., Huang, Q., Li, W., & Deng, W. (2007). A cellular automaton-based simulator for silicon anisotropic etching processes considering high index planes. Journal of Micromechanics and Microengineering, 17(4), S38-S49. doi:10.1088/0960-1317/17/4/s03Gosalvez, M. A., Yan Xing, & Sato, K. (2008). Analytical Solution of the Continuous Cellular Automaton for Anisotropic Etching. Journal of Microelectromechanical Systems, 17(2), 410-431. doi:10.1109/jmems.2008.916339Zhou, Z., Huang, Q., & Li, W. (2009). Modeling and Simulations of Anisotropic Etching of Silicon in Alkaline Solutions with Experimental Verification. Journal of The Electrochemical Society, 156(2), F29. doi:10.1149/1.3031485Rangsten, P., Hedlund, C., Katardjiev, I. V., & Bäcklund, Y. (1998). Etch rates of crystallographic planes inZ-cut quartz - experiments and simulation. Journal of Micromechanics and Microengineering, 8(1), 1-6. doi:10.1088/0960-1317/8/1/001Tellier, C. R., & Leblois, T. G. (2000). Micromachining of quartz plates: determination of a database by combined stereographic analysis and 3-D simulation of etching shapes. IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 47(5), 1204-1216. doi:10.1109/58.869067Hedlund, C., Lindberg, U., Bucht, U., & Soderkvist, J. (1993). Anisotropic etching of Z-cut quartz. Journal of Micromechanics and Microengineering, 3(2), 65-73. doi:10.1088/0960-1317/3/2/006Liang, J., Kohsaka, F., Matsuo, T., & Ueda, T. (2007). Wet Etched High Aspect Ratio Microstructures on Quartz for MEMS Applications. IEEJ Transactions on Sensors and Micromachines, 127(7), 337-342. doi:10.1541/ieejsmas.127.337Gosálvez, M. A., Xing, Y., Sato, K., & Nieminen, R. M. (2009). Discrete and continuous cellular automata for the simulation of propagating surfaces. Sensors and Actuators A: Physical, 155(1), 98-112. doi:10.1016/j.sna.2009.08.012Zhenjun Zhu, & Chang Liu. (2000). Micromachining process simulation using a continuous cellular automata method. Journal of Microelectromechanical Systems, 9(2), 252-261. doi:10.1109/84.846706Gosálvez, M. A., Xing, Y., Sato, K., & Nieminen, R. M. (2008). Atomistic methods for the simulation of evolving surfaces. Journal of Micromechanics and Microengineering, 18(5), 055029. doi:10.1088/0960-1317/18/5/055029Ferrando, N., Gosálvez, M. A., Cerdá, J., Gadea, R., & Sato, K. (2011). Octree-based, GPU implementation of a continuous cellular automaton for the simulation of complex, evolving surfaces. Computer Physics Communications, 182(3), 628-640. doi:10.1016/j.cpc.2010.11.004Mühlenbein, H., & Schlierkamp-Voosen, D. (1993). Predictive Models for the Breeder Genetic Algorithm I. Continuous Parameter Optimization. Evolutionary Computation, 1(1), 25-49. doi:10.1162/evco.1993.1.1.25Kohsaka, F., Liang, J., Matsuo, T., & Ueda, T. (2007). High Sensitive Tilt Sensor for Quartz Micromachining. IEEJ Transactions on Sensors and Micromachines, 127(10), 431-436. doi:10.1541/ieejsmas.127.43
Resting-State Brain Organization Revealed by Functional Covariance Networks
BACKGROUND: Brain network studies using techniques of intrinsic connectivity network based on fMRI time series (TS-ICN) and structural covariance network (SCN) have mapped out functional and structural organization of human brain at respective time scales. However, there lacks a meso-time-scale network to bridge the ICN and SCN and get insights of brain functional organization. METHODOLOGY AND PRINCIPAL FINDINGS: We proposed a functional covariance network (FCN) method by measuring the covariance of amplitude of low-frequency fluctuations (ALFF) in BOLD signals across subjects, and compared the patterns of ALFF-FCNs with the TS-ICNs and SCNs by mapping the brain networks of default network, task-positive network and sensory networks. We demonstrated large overlap among FCNs, ICNs and SCNs and modular nature in FCNs and ICNs by using conjunctional analysis. Most interestingly, FCN analysis showed a network dichotomy consisting of anti-correlated high-level cognitive system and low-level perceptive system, which is a novel finding different from the ICN dichotomy consisting of the default-mode network and the task-positive network. CONCLUSION: The current study proposed an ALFF-FCN approach to measure the interregional correlation of brain activity responding to short periods of state, and revealed novel organization patterns of resting-state brain activity from an intermediate time scale
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