6,017 research outputs found
Ethnobotanical Survey of Medicinal Plants in West Kordofan (Western Sudan)
The aim of the present study was primarily to evaluate the medicinal uses of the plants known to some western Kordofan tribes and to encourage preservation of their culture, conservation and sustainable utilization of the plant wealth. The present study revealed a record of 49 plant species belonging to 26 families which are used in the folk medicine of West Kordofan, Sudan. It is believed to be a form of healthcare in many aspects of curing practices. The plants were arranged alphabetically by their family name followed by species name, local name, parts used, mode of preparation and medicinal uses. This wisdom available with the tribes is transmitted only through oral communication therefore needs conservation
Nonlinear stability of magnetic islands in a rotating helical plasma
Coexistence of the forced magnetic reconnection by a resonant magnetic perturbation (RMP) and the curvature-driven tearing mode is investigated in a helical (stellarator) plasma rotated by helical trapped particle-induced neoclassical flows. A set of Rutherford-type equations of rotating magnetic islands and a poloidal flow evolution equation is revisited. Using the model, analytical expressions of criteria of spontaneous shrinkage (self-healing) of magnetic islands and sudden growth of locked magnetic islands (penetration of RMP) are obtained, where nonlinear saturation states of islands show bifurcation structures and hysteresis characteristics. Considering radial profile of poloidal flows across magnetic islands, it is found that the self-healing is driven by neoclassical viscosity even in the absence of micro-turbulence-induced anomalous viscosity. Effects of unfavorable curvature in stellarators are found to modify the critical values. The scalings of criteria are consistent with low-β experiments in the large helical device
Newcomers Meet the Intracluster Medium in the Coma Cluster
A main topic at this meeting is how galaxies are affected when they enter for
the first time the cluster environment from the outskirts. Most of the times we
are forced to infer the environmental effects indirectly, relying on systematic
variations of galaxy properties with environment, but there aren't many
examples of direct observations able to unveil ongoing transformations taking
place, and the corresponding mechanism producing it. We present a case in which
it is possible to identify the cluster environment, and in particular the
intracluster medium and the recent infall history of galaxies onto the cluster,
as the cause for a recent, abrupt change in the evolutionary history of
galaxies.Comment: 5 pages, 1 postscript figure -- to appear in "Outskirts of Galaxy
Clusters: intense life in the suburbs", IAU Colloquium N. 195, 2004, ed. A
Diaferi
Self-annihilation of Magnetic Islands in Helical Plasmas
The evolution of the magnetic island which is induced by the resonant deformation by external currents in helical systems (such as LHD) is analyzed. The defect of the bootstrap current, caused by the magnetic island, has a parity which reduces the size of the magnetic island, if the bootstrap current enhances the vacuum rotational transform. The width of the externally-driven magnetic island can be suppressed to the level of ion banana width if the pressure gradient exceeds a threshold value. This island annihilation is self-sustained. That is, the annihilation continues, for fixed beta-value, until the external drive for island generation exceeds a threshold. Effects of the reversal of the direction of the bootstrap current and of the sign of radial electric field are also investigated. The possibility of the neoclassical tearing mode in the LHD-like plasma is discussed
<Advanced Energy Generation Division> Advanced Atomic Energy Research Section
3-1. Research Activities in 202
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