Solar flare and CME predictions using numerical MHD simulations

According to observational and theoretical data the solar flare radiation and coronal mass ejection(CME) are manifestations of the same explosive process, which takes place high in the solar corona. In some solar flares one of these manifestations can be weak and can not be observed, in other flares both of these manifestations are present. CMEs are the most important cause of substorm appearances in the magnetosphere. For solar flare and CME predictions, it is need to have information about main processes of these explosive phenomena and to estimate the possibility of their occurrences. The energy for solar flare can be accumulated in a current sheet. For MHD simulation of this process the program PERESVET is developed that uses observed distributions of magnetic field on the photosphere as the boundary conditions. The MHD simulation showed, that the current sheet can be vertical, horizontal, or inclined to some angles to the photosphere depending on the magnetic field distribution on the photosphere and its evolution. The vertical current sheet can produce the CME, because the magnetic tension force accelerates plasma from the Sun. The CME prognosis is based on information about the position of current sheet in the solar corona

The mechanism of energy release and field-aligned current generation during substorms and solar flares

In this paper, the mechanisms of field-aligned current (FAC) and westward electrojet generation are considered on the base of space measurements and laboratory simulation. Upward and downward FAC are generated in the Earth magnetotail current sheet (CS) due to the tail earthward electric field. They are connected in the ionosphere by the Pedersen current. The FAC enhancement takes place during magnetic reconnection and explosive energy release at a substorm. Electron acceleration in upward FAC produces fast electron precipitation and aurora appearance. The westward electrojet (Hall current) is located between two opposite directed sheets of FAC. The current in the jet is determined by the Hall conductivity in the ionosphere. The similar current systems in the solar corona are responsible for energy transfer to the chromosphere during a solar flare. The solar flare model is built on the base of observations and 3D MHD numerical simulation for compressible resistive plasma

Development of High Performance DC Fuse for Electric Vehicle and Its Features

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Quinolizidines. VIII. Structure and Synthesis of the Alangium Alkaloid Alangicine : Syntheses of (±)- and (+)-Alangicines

The first total synthesis of alangicine (3), an Alangium lamarckii alkaloid, has been achieved in the form of a racemic modification by means of an initial alkaline hydrolysis of the (±)-tricyclic ester 6 and succeeding steps proceeding through the intermediates (±)-7,(±)-10,and (±)-9. A parallel synthetic route starting with the (-)-tricyclic ester 6,derived from (+)-cincholoipon ethyl ester (8), produced the chiral target molecule (+)-3 with alangicine unequivocally established the structure and absolute stereochemistry of this alkaloid. The ^C nuclear magnetic resonance spectra of (±)-alangicine (3) and the ipecac and Alangium alkaloid psychotrine (18) confirmed their endocyclic double bond structures in the dihydroisoquinoline moiety. Catalytic reductions of 11,(±)-12,and 15 using hydrogen and Pd-C were investigated, and the results have shown that hydrogenolysis of the benzyloxy group proceeds much faster than saturation of the endocyclic C=N bond

In-Situ Measurement of Ionospheric E-Region Plasma Irregularities over Taiwan

One ion trap (IT) and one retarding potential analyzer (RPA) onboard the Taiwan Sounding Rocket V (SR-V) were launched to measure ionospheric plasma irregularities on 18 January 2006. After the fairing separated, voltage readings (VG1) of the first grid (G1) in the IT indicated abnormally high negative voltages appeared at the upleg between 83.7 and 120.1 km altitude for 19.7 seconds. It is postulated G1 had temporarily shorted out with the other two grids. Such the anomaly in the VG1 brought out the expansion of a plasma sheath around opening of the IT. More ions were attracted into the collector. Remarkable ion currents detected by the IT led to malfunctions of the RPA simultaneously. In this article, laboratory simulations and the International Reference Ionosphere model are performed to evaluate scale factors for the IT to the anomaly. The calibrated total ion concentration profile at the upleg indicates a peak density of the Es layer at 93.0 km altitude of about 6.9 × 103 # cm-3 with a thickness of 3.4 km. It is very similar to that at the downleg. It implies that the SR-V might encounter the same Es layer twice in a distance of 150 km away

Interferon-alpha-induced mTOR activation is an anti-hepatitis C virus signal via the phosphatidylinositol 3-kinase-Akt-independent pathway.

OBJECT: The interferon-induced Jak-STAT signal alone is not sufficient to explain all the biological effects of IFN. The PI3-K pathways have emerged as a critical additional component of IFN-induced signaling. This study attempted to clarify that relationship between IFN-induced PI3-K-Akt-mTOR activity and anti-viral action. RESULT: When the human normal hepatocyte derived cell line was treated with rapamycin (rapa) before accretion of IFN-alpha, tyrosine phosphorylation of STAT-1 was diminished. Pretreatment of rapa had an inhibitory effect on the IFN-alpha-induced expression of PKR and p48 in a dose dependent manner. Rapa inhibited the IFN-alpha inducible IFN-stimulated regulatory element luciferase activity in a dose-dependent manner. However, wortmannin, LY294002 and Akt inhibitor did not influence IFN-alpha inducible luciferase activity. To examine the effect of PI3-K-Akt-mTOR on the anti-HCV action of IFN-alpha, the full-length HCV replication system, OR6 cells were used. The pretreatment of rapa attenuated its anti-HCV replication effect in comparison to IFN-alpha alone, whereas the pretreatment with PI3-K inhibitors, wortmannin and LY294002 and Akt inhibitor did not influence IFN-induced anti-HCV replication. CONCLUSION: IFN-induced mTOR activity, independent of PI3K and Akt, is the critical factor for its anti-HCV activity. Jak independent mTOR activity involved STAT-1 phosphorylation and nuclear location, and then PKR is expressed in hepatocytes

Performance of a newly developed plug-in hybrid boat

We have produced a new-type of plug-in hybrid boat. This boat has excellent environment characteristics running by electricity, while having the ability of long-distance cruising and long distance reliability because of the diesel engine. The excellent performances of this plug-in hybrid boat system are described