3,717 research outputs found
Effect of interfacial strain on spin injection and spin polarization of Co2CrAl/NaNbO3/Co2CrAl magnetic tunneling junction
First-principles calculations were carried out to investigate interfacial
strain effects on spin injection and spin polarization of a magnetic tunnel
junction consisting of half-metallic full-Heusler alloy Co2CrAl and
ferroelectric perovskite NaNbO3. Spin-dependent coherent tunneling was
calculated within the framework of non-equilibrium Green's function technique.
Both spin polarization and tunnel magnetoresistance (TMR) are affected by the
interfacial strain but their responses to compressive and tensile strains are
different. Spin polarization across the interface is fully preserved under a
compressive strain due to stronger coupling between interfacial atoms, whereas
a tensile strain significantly enhances interface states and lead to
substantial drops in spin polarization and TMR
N-Cyclohexyl-N-{[3-(4,6-dimethoxypyrimidin-2-yloxy)pyridin-2-yl]methyl}4,6-dimethoxypyrimidin-2-amine
In the title compound, C24H30N6O5, the cyclohexyl ring adopts a chair conformation, while the remainder of the molecule adopts a U-shape. The dihedral angles between the pyridine ring and the pendant pyrimidine rings are 69.04 (12) and 75.99 (9)°. The two pyrimidine rings, however, are nearly parallel to one another, with a dihedral angle of 8.56 (15)° between them. They are also involved in an intramolecular π–π stacking interaction with a distance of 3.6627 (18) Å between the ring centroids. In the crystal, C—H⋯O contacts link the molecules into chains along the b axis
Detrended fluctuation analysis on the correlations of complex networks under attack and repair strategy
We analyze the correlation properties of the Erdos-Renyi random graph (RG)
and the Barabasi-Albert scale-free network (SF) under the attack and repair
strategy with detrended fluctuation analysis (DFA). The maximum degree k_max,
representing the local property of the system, shows similar scaling behaviors
for random graphs and scale-free networks. The fluctuations are quite random at
short time scales but display strong anticorrelation at longer time scales
under the same system size N and different repair probability p_re. The average
degree , revealing the statistical property of the system, exhibits
completely different scaling behaviors for random graphs and scale-free
networks. Random graphs display long-range power-law correlations. Scale-free
networks are uncorrelated at short time scales; while anticorrelated at longer
time scales and the anticorrelation becoming stronger with the increase of
p_re.Comment: 5 pages, 4 figure
Stabilization of the Fractional-Order Chua Chaotic Circuit via the Caputo Derivative of a Single Input
A modified fractional-order Chua chaotic circuit is proposed in this paper, and the chaotic attractor is obtained for q=0.98. Based on the Mittag-Leffler function in two parameters and Gronwall’s Lemma, two control schemes are proposed to stabilize the modified fractional-order Chua chaotic system via the Caputo derivative of a single input. The numerical simulation shows the validity and feasibility of the control scheme
CIBZ, a Novel BTB Domain-Containing Protein, Is Involved in Mouse Spinal Cord Injury via Mitochondrial Pathway Independent of p53 Gene
Spinal cord injury (SCI) induces both primary uncontrollable mechanical injury and secondary controllable degeneration, which further results in the activation of cell death cascades that mediate delayed tissue damage. To alleviate its impairments and seek for an effective remedy, mRNA differential display was used to investigate gene mRNA expression profiling in mice following SCI. A specific Zinc finger and BTB domain-containing protein, CIBZ, was discovered to implicate in the SCI process for the first time. Further researches indicated that CIBZ was extensively distributed in various tissues, and the expression level was highest in muscle, followed by spinal cord, large intestine, kidney, spleen, thymus, lung, cerebrum, stomach, ovary and heart, respectively. After injury, the CIBZ expression decreased dramatically and reached the lowest level at 8 h, but it gradually increased to the maximal level at 7 d. Caspase-3 and C-terminal-binding protein (CtBP), two CIBZ-related proteins, showed similar tendency. Interestingly, p53 expression remained constant in all groups. Via flow cytometry (FCM) analysis, it was found that the cell death rate in SCI group markedly increased and reached the highest value 1 d after surgery and the mitochondrial transmembrane potential (ΔΨm) at 1 d was the lowest in all groups. Taken together, it is suggested that: (i) in the presence of CtBP, CIBZ gene is involved in secondary injury process and trigger the activation of apoptotic caspase-3 and bax genes independent of p53; (ii) abrupt down-regulation of CtBP at 8 h is a sign of mitochondria dysfunction and the onset of cell death; (iii) it could be used as an inhibitor or target drug of caspase-3 gene to improve spinal cord function
Profiling and Identification of the Metabolites of Evodiamine in Rats using Ultra–Performance Liquid Chromatography with Linear Ion Trap Orbitrap Mass Spectrometer
Purpose: To develop a highly sensitive and specific ultra-performance liquid chromatography with linear ion trap Orbitrap mass spectrometer (UPLC-LTQ-Orbitrap) method to profile and identify the metabolites of evodiamine in rats.Methods: First, blood samples were collected after oral administration of evodiamine to rats (50 mg/kg). Next, the plasma samples were pretreated using a solid-phase extraction (SPE) method. Finally, all the samples were analyzed by ultra-performance liquid chromatography LTQ-Orbitrap mass spectrometry (UPLC-LTQ- Orbitrap) coupled with electrospray ionization source (ESI) in negative mode.Results: A total of 7 metabolites (2 phase I and 4 phase II metabolites, including 4 new metabolites, viz, 10-hydroxyevodiamine sulfate, 10-hydroxyevodiamine sulfate, 10-hydroxyevodiamine glucuronide and 3-hydroxyevodiamine glucuronide) as well as the parent drug itself , were detected and identified based on accurate mass measurements, fragmentation patterns, and chromatographic retention times. The in vivo metabolic reactions of evodiamine in rats were hydroxylation, hydroxylation + sulfate conjugation, and hydroxylation + glucuronidation.Conclusion: These results provide better understanding of the metabolism of evodiamine as well as strong indications of the effective forms of the drug in vivo.Keywords: Evodiamine, Ultra–performance liquid chromatography with linear ion trap-Orbitrap, Hydroxyevodiamine sulfate, Hydroxyevodiamine glucuronide, Metabolite
1-Benzoyl-3-chloroazepan-2-one
In the crystal structure of the title compound, C13H14ClNO2, intermolecular C—H⋯O interactions link the molecules into a two-dimensional network
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