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61.

Background  

Gamma-aminobutyric acid type A receptors (GABAA-Rs) are the major inhibitory receptors in the mammalian brain and are modulated by a number of sedative/hypnotic drugs including benzodiazepines and anesthetics. The significance of specific GABAA-Rs subunits with respect to behavior and in vivo drug responses is incompletely understood. The γ2 subunit is highly expressed throughout the brain. Global γ2 knockout mice are insensitive to the hypnotic effects of diazepam and die perinatally. Heterozygous γ2 global knockout mice are viable and have increased anxiety-like behaviors. To further investigate the role of the γ2 subunit in behavior and whole animal drug action, we used gene targeting to create a novel mouse line with attenuated γ2 expression, i.e., γ2 knockdown mice.  相似文献   
62.
Time‐resolved Raman spectroscopy, spatially offset Raman spectroscopy and time‐resolved spatially offset Raman spectroscopy (TR‐SORS) have proven their capability for the non‐invasive profiling of deep layers of a sample. Recent studies have indicated that TR‐SORS exhibits an enhanced selectivity toward the deep layers of a sample. However, the enhanced depth profiling efficiency of TR‐SORS, in comparison with time‐resolved Raman spectroscopy and spatially offset Raman spectroscopy, is yet to be assessed and explained in accordance to the synergistic effects of spatial and temporal resolutions. This study provides a critical investigation of the depth profiling efficiency of the three deep Raman techniques. The study compares the efficiency of the various deep Raman spectroscopy techniques for the stand‐off detection of explosive precursors hidden in highly fluorescing packaging. The study explains for the first time the synergistic effects of spatial and temporal resolutions in the deep Raman techniques and their impact on the acquired spectral data. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
63.
Semiconductor quantum dots are among the leading candidates for next-generation nanoscale devices due to their tunable size, shape, and low energy consumption. Here we apply quantum optimal control theory to coherently manipulate the single-electron charge distribution in quantum-dot lattices of various sizes. In particular, we show that to control the charge distribution it is sufficient to optimize the gate voltage acting on a single quantum dot in the lattice. We generally find yields around 99% in the picosecond time scale when using realistic models for the quantum-dot lattices on a real-space grid. We analyze and discuss both the limitations of the model regarding the gate parameters as well as the potential of the scheme for applications as quantum-dot cellular automata.  相似文献   
64.
We show that under the Bernoulli initial condition two kinks in the cellular automaton (CA) 18/256 will annihilate each other with probability one. It turns out that there is an equivalent statement in terms of percolation in the simple binary additive CA. Namely, under the Bernoulli initial condition, l's do not percolate in the binary additive CA.  相似文献   
65.
A complicated low energy structure in the O K X-ray emission of MgO and CaO is reported. The onset of this structure falls at about 15 eV and some structure is discernible still at about 80 eV below the line. The main features of this structure are interpreted as KLL radiative Auger transitions. Transitions from initial MO states, consisting mainly of metal p and ligand s wave functions, to the final O 1s state are proposed in CaO.  相似文献   
66.

We study dimensional properties of porous measures on . As a corollary of a theorem describing the local structure of nearly uniformly porous measures we prove that the packing dimension of any Radon measure on has an upper bound depending on porosity. This upper bound tends to as porosity tends to its maximum value.

  相似文献   

67.
Faulhuber and Steinerberger conjectured that the logarithmic derivative of ?4 has the property that y2?4(y)/?4(y) is strictly decreasing and strictly convex. In this small note, we prove this conjecture.  相似文献   
68.
The influence of ligand structure of hafnocenes on activation of the polymerization catalysts has been studied by quantum chemical methods. Altogether 54 hafnocenes were included in the analysis, supplemented by four zirconocenes for comparison. The trends in structural and electronic parameters relevant in the catalyst activation step were studied for the dichloride, dimethyl and cationic monomethyl forms of the catalysts. The effects of ligand modifications were analyzed as functions of the metal, ancillary cyclopentadienyl-based ligand, ligand substituent and the ligand bridge, making comparisons to experimental data. Generally, large aromatic ligands together with electron donating ligand substituents stabilize the catalytically active species, thus facilitating the catalyst activation process. The obtained trends are expected to aid in the development of new high-performance polymerization catalysts.  相似文献   
69.
The influence of catalyst components in the copper–TEMPO (2,2,6,6‐tetramethylpiperidine N‐oxide) catalysed aerobic oxidation of alcohols was investigated. The type and amount of base greatly influences reactivity. The bipyridyl ligand concentration had no major influence on catalysis, but excessive amounts led to a decrease in activity for longer reaction times. The kinetic dependency for TEMPO was found to be 1.15, and for copper 2.25, which is an indication of a binuclear catalytic system. Optimised conditions with various allylic and aliphatic alcohols give good to excellent rapid oxidations.  相似文献   
70.
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