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81.
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Nadia Tagnaouti Sven Loebrich Frank Heisler Yvonne Pechmann Susanne Fehr Adèle De Arcangelis Elisabeth Georges-Labouesse Josephine C Adams Matthias Kneussel 《BMC neuroscience》2007,8(1):28
Background
The kelch repeat protein muskelin mediates cytoskeletal responses to the extracellular matrix protein thrombospondin 1, (TSP1), that is known to promote synaptogenesis in the central nervous system (CNS). Muskelin displays intracellular localization and affects cytoskeletal organization in adherent cells. Muskelin is expressed in adult brain and has been reported to bind the Cdk5 activator p39, which also facilitates the formation of functional synapses. Since little is known about muskelin in neuronal tissues, we here analysed the tissue distribution of muskelin in rodent brain and analysed its subcellular localization using cultured neurons from multiple life stages. 相似文献83.
Iron Precursor Decomposition in the Magnesium Combustion Flame: A New Approach for the Synthesis of Particulate Metal Oxide Nanocomposites 下载免费PDF全文
Amir R. Gheisi Matthias Niedermaier Gerold Tippelt Werner Lottermoser Johannes Bernardi Oliver Diwald 《Particle & Particle Systems Characterization》2017,34(10)
Powders of Fe–Mg–O nanocomposite particles have been grown using a novel chemical vapor synthesis approach that employs the decomposition of a metalorganic precursor inside the metal combustion flame. After annealing in controlled gas atmospheres composition distribution functions, structure and phase stability of the obtained magnesiowüstite nanoparticles are measured with a combination of techniques such as inductively coupled plasma‐optical emission spectroscopy, energy dispersive X‐ray spectroscopy, X‐ray diffraction, and scanning and transmission electron microscopy. Complementary Mössbauer spectroscopy measurements reveal that depending on Fe loading and temperature of annealing either metastable and superparamagnetic solid solutions of Fe3+ ions in periclase (MgO) or phase separated mixtures of MgO and ferrimagnetic magnesioferrite (MgFe2O4) nanoparticles can be obtained. The described combustion technique represents a novel concept for the production of mixed metal oxide nanoparticles. Adressing the impact of selected annealing protocols, this study underlines the great potential of vapor phase grown non‐equilibrium solids, where thermal processing provides means to trigger phase separation and, concomitantly, the emergence of new magnetic properties. 相似文献
84.
Yanagisawa H Hengsberger M Leuenberger D Klöckner M Hafner C Greber T Osterwalder J 《Physical review letters》2011,107(8):087601
Energy distribution curves of laser-induced electron pulses from a tungsten tip have been measured as a function of tip voltage and laser power. Electron emission via tunneling through and/or excitation over the surface barrier from photoexcited nonequilibrium electron distributions are clearly observed. The spectral shapes largely vary with the emission processes and are strongly affected by electron dynamics. Simulations successfully reproduce the spectra, thus allowing direct insight into the involved electron dynamics and revealing the temporal tunability of electron emission via the two experimental parameters. These results should be useful to optimize the pulse characteristics for many applications based on ultrafast laser-induced electron emission. 相似文献
85.
Electronic surface states can interact with adsorbate orbitals only if they have the same symmetry with respect to the adsorption site. Therefore, the interaction between a surface state and a particular adsorbate orbital provides information about the symmetry properties of the adsorption site. This is discussed for the adsorption of hydrogen and ethylene on Ni(110). 相似文献
86.
Matthias Schmidt 《Zeitschrift für Physik B Condensed Matter》1994,95(3):327-330
We consider theq=3 Potts model in three dimensions by Monte Carlo simulations. The microcanonical density of states is calculated as a function of the internal energy of the system. We extrapolate the data for the simulated finite systems to the thermo-dynamic limit and find a discontinuous phase transition. This method is checked in the two-dimensional case, where exact results are known. 相似文献
87.
Matthias Kunik 《Mathematical Methods in the Applied Sciences》1992,15(7):495-509
We examine the existence and regularity results for a scalar conservation law with a convexity condition and solve its weak solution with shocks by using a special method of characterization combined with a representation formula for the weak solution. 相似文献
88.
Heidrun Weber Matthias Vojta 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,53(2):185-192
Motivated by impurity-induced magnetic ordering phenomena in spin-gap materials like TlCuCl3,
we develop a mean-field theory for strongly disordered antiferromagnets,
designed to capture the broad distribution of coupling constants
in the effective model for the impurity degrees of freedom.
Based on our results,
we argue that in the presence of random magnetic couplings the conventional
first-order spin-flop transition of an anisotropic antiferromagnet
is split into two transitions at low temperatures,
associated with separate order parameters along and perpendicular
to the field axis.
We demonstrate the existence of either a bicritcal point or a critical endpoint
in the temperature–field phase diagram,
with the consequence that signatures of
the spin flop are more pronounced at elevated temperature. 相似文献
89.
Schmidt M Voth E Schneider CA Theissen P Wagner R Baer FM Schicha H 《Magnetic resonance imaging》2004,22(2):229-236
Identification of akinetic but viable myocardium is important for the selection of patients for coronary revascularization. In order to assess predictive values of end-diastolic wall thickness and dobutamine induced wall thickening obtained by magnetic resonance imaging (MRI) and [18F]Fluorodeoxyglucose uptake assessed by positron emission tomography (F-18-FDG-PET), these parameters were compared to recovery of left ventricular function after successful revascularization. Forty patients with chronic myocardial infarction and regional a- or dyskinesia by ventriculography underwent rest- and dobutamine-MRI studies (10 microg dobutamine/kg body weight/min) and F-18-FDG-PET. Viability of the infarct region was considered to be present if; 1) end-diastolic wall thickness was > or =5.5 mm; 2) dobutamine induced wall thickening > or =2 mm could be measured; and 3) normalized F-18-FDG-uptake was > or =50% in > or =50% of akinetic segments. Preserved end-diastolic wall thickness was found in 32/40 patients, functional improvement during dobutamine infusion in 26/40 patients and preserved F-18-FDG-uptake in 29/40 patients. After revascularization regional left ventricular function improved in 25/40 patients. Positive and negative predictive values and diagnostic accuracy were 78%, 100%, and 83% for preserved end-diastolic wall thickness, 92%, 93%, and 93% for dobutamine inducible contraction reserve and 86%, 100%, and 90% for preserved F-18-FDG-uptake. Quantitative assessment of dobutamine induced systolic wall thickening by MRI and F-18-FDG-uptake by PET are highly accurate techniques for the identification of viable myocardium and prediction of functional recovery after successful revascularization. Preserved end-diastolic wall thickness results in an overestimation of viable myocardium compared to functional improvement, but wall thickness <5.5 mm excludes recovery of regional function. 相似文献
90.