1,264 research outputs found
1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine
In the title compound, C21H16N4O, the central tetrazine ring adopts an unsymmetrical boat conformation with the two N atoms as the bow and stern. The crystal packing is stabilized by intermolecular N—H—O hydrogen bonds
Effects of current on nanoscale ring-shaped magnetic tunnel junctions
We report the observation and micromagnetic analysis of current-driven
magnetization switching in nanoscale ring-shaped magnetic tunnel junctions.
When the electric current density exceeds a critical value of the order of
A/cm, the magnetization of the two magnetic rings can be
switched back and forth between parallel and antiparallel onion states.
Theoretical analysis and micromagnetic simulation show that the dominant
mechanism for the observed current-driven switching is the spin torque rather
than the current-induced circular Oersted field
Abnormal magnetoresistance behavior in Nb thin film with rectangular antidot lattice
Abnormal magnetoresistance behavior is found in superconducting Nb films
perforated with rectangular arrays of antidots (holes). Generally
magnetoresistance were always found to increase with increasing magnetic field.
Here we observed a reversal of this behavior for particular in low temperature
or current density. This phenomenon is due to a strong 'caging effect' which
interstitial vortices are strongly trapped among pinned multivortices.Comment: 4 pages, 2 figure
Oscillatory tunnel magnetoresistance in double barrier magnetic tunnel junctions
We report an unconventional oscillatory tunnel magnetoresistance as a function of the applied bias in double barrier magnetic tunnel junctions that were made of two Al2O3 barriers sandwiched by three ferromagnetic layers. When the center ferromagnetic layer is aligned antiparallel to the top and bottom magnetic layers, a distinct magnetoresistance oscillation appears with respect to the increase of the bias voltage at 4.2 K and at room temperature. The period of the oscillation is about 1.6 mV
Investigation of Interactions between Thrombin and Ten Phenolic Compounds by Affinity Capillary Electrophoresis and Molecular Docking
Thrombin plays a vital role in blood coagulation, which is a key process involved in thrombosis by promoting platelet aggregation and converting fibrinogen to form the fibrin clot. In the receptor concept, drugs produce their therapeutic effects via interactions with the targets. Therefore, investigation of interaction between thrombin and small molecules is important to find out the potential thrombin inhibitor. In this study, affinity capillary electrophoresis (ACE) and in silico molecular docking methods were developed to study the interaction between thrombin and ten phenolic compounds (p-hydroxybenzoic acid, protocatechuic acid, vanillic acid, gallic acid, catechin, epicatechin, dihydroquercetin, naringenin, apigenin, and baicalein). The ACE results showed that gallic acids and six flavonoid compounds had relative strong interactions with thrombin. In addition, the docking results indicated that all of optimal conformations of the six flavonoid compounds were positioned into the thrombin activity centre and had interaction with the HIS57 or SER195 which was the key residue to bind thrombin inhibitors such as argatroban. Herein, these six flavonoid compounds might have the potential of thrombin inhibition activity. In addition, the developed method in this study can be further applied to study the interactions of other molecules with thrombin
Therapeutic effects of Jiaotai pill on rat insomnia via regulation of GABA signal pathway
Purpose: To investigate the therapeutic effects of Jiaotai pill (JTP) on rats with insomnia induced by pchlorophenylalanine (PCPA).Methods: Rats with PCPA-induced insomnia were divided into 5 groups (n = 10), made up of control group, positive treatment group (estazolam 0.1 mg/kg), and 3 JTP treatment groups (0.6, 1.2 and 2.4 g/kg). Another group of 10 rats were treated as normal group. Rats in normal and control groups were treated with normal saline (10 mL/kg). After 14 days of drug treatment, the rats were injected intraperitoneally with sodium pentobarbital (45 mg/kg) and thereafter, latent period and sleeping time were recorded, while contents of γ-aminobutyric acid (GABA) and glutamic acid (Glu) in hypothalamus were determined by high performance liquid chromatography (HPLC). Furthermore, the expressions of glutamate decarboxylase 65 (GAD-65), glutamate decarboxylase 67 (GAD-67), GABAaminotransferase (GABA)-T, anti-GABA transporter 1 (GAT)-1, anti-GABA transporter (GAT)-3, and GABA receptors (GABA-A and GABA-B) in the hypothalamus were analyzed by western blotting assay.Results: The results showed that JTP (0.6, 1.2 and 2.4 g/kg) significantly shortened latent period and prolonged sleeping time (p < 0.01). JTP also increased GABA level (p < 0.01), but decreased Glu contents of the rat hypothalamus (p < 0.01). Western blotting data indicate that JTP significantly upregulated the levels of GAD-65 (p < 0.01), GAD-67 (p < 0.05), GAT-1 (p < 0.01), GAT-3 (p < 0.01), GABA-A (p < 0.01) and GABA-B (p < 0.01), while the level of GABA-T was down-regulated.Conclusion: The results demonstrate that JTP possesses significant sedative effects on insomnia in rats, most probably through a mechanism involving GABA signal pathway.Keywords: Jiaotai pill, Insomnia, GABA, Glutamate, Estazolam, GABA signal pathwa
An analysis of risk factors of non-fatal drowning among children in rural areas of Guangdong Province, China: a case-control study
<p/> <p>Background</p> <p>Drowning is a major cause of morbidity and mortality for children, yet non-fatal drowning remains poorly understood. The aim of this study was to explore potential modifiable risk factors of non-fatal drowning among children in rural areas of China.</p> <p>Methods</p> <p>A cross-sectional survey was first conducted to obtain non-fatal drowning cases, and 7432 students in grades three to eight from 17 schools participated in the cross sectional survey. Of these, 805 students reported that they experienced non-fatal drowning in the previous year. Then 368 cases were selected randomly to participate in a 1:1 matched case-control study. Each drowning case was matched by one control with the same sex and similar age (the gap less than 2 years) who was selected randomly from the same class.</p> <p>Results</p> <p>Boys were more likely to be involved in non-fatal drowning. Non-fatal drowning most often happened in the afternoon (65.1%) and natural bodies of water were the most common sites of drowning (71.1%). Swimming, diving and playing in natural waters were the leading activities that preceded non-fatal drowning. The significant risk factors for non-fatal drowning were swimming in natural waters without adult supervision (OR = 3.40, 95% CI: 1.92-6.03), playing in or beside natural waters (OR = 2.08, 95% CI: 1.17-3.70) and poor swimming skills (OR = 2.74, 95% CI: 1.14-6.62). However, the following variables were protective factors: supervisor aged 30 years or over (OR = 0.20, 95% CI: 0.09-0.49) and no water activities (OR = 0.36, 95% CI: 0.18-0.70).</p> <p>Conclusions</p> <p>The reduction in dangerous water activities, swimming training and enhancement in supervision among children might decrease the risk of non-fatal drowning.</p
A Hybrid Reliable Heuristic Mapping Method Based on Survivable Virtual Networks for Network Virtualization
The reliable mapping of virtual networks is one of the hot issues in network virtualization researches. Unlike the traditional protection mechanisms based on redundancy and recovery mechanisms, we take the solution of the survivable virtual topology routing problem for reference to ensure that the rest of the mapped virtual networks keeps connected under a single node failure condition in the substrate network, which guarantees the completeness of the virtual network and continuity of services. In order to reduce the cost of the substrate network, a hybrid reliable heuristic mapping method based on survivable virtual networks (Hybrid-RHM-SVN) is proposed. In Hybrid-RHM-SVN, we formulate the reliable mapping problem as an integer linear program. Firstly, we calculate the primary-cut set of the virtual network subgraph where the failed node has been removed. Then, we use the ant colony optimization algorithm to achieve the approximate optimal mapping. The links in primary-cut set should select a substrate path that does not pass through the substrate node corresponding to the virtual node that has been removed first. The simulation results show that the acceptance rate of virtual networks, the average revenue of mapping, and the recovery rate of virtual networks are increased compared with the existing reliable mapping algorithms, respectively
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