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1.
The lower-hybrid drift instability is simulated in an ion-scale current sheet using a fully kinetic approach with values of the ion to electron mass ratio up to m(i)/m(e)=1836. Although the instability is localized on the edge of the layer, the nonlinear development increases the electron flow velocity in the central region resulting in a strong bifurcation of the current density and significant anisotropic heating of the electrons. This dramatically enhances the collisionless tearing mode and may lead to the rapid onset of magnetic reconnection for current sheets near the critical scale. 相似文献
2.
Trent D Lund Timothy W West Lilyan Y Tian Lihong H Bu Daniel L Simmons Kenneth DR Setchell Herman Adlercreutz Edwin D Lephart 《BMC neuroscience》2001,2(1):20-13
Background
In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined. 相似文献3.
4.
Don S. Lemons Dan Winske William Daughton Brian Albright 《Journal of computational physics》2009,228(5):1391-1403
We construct and investigate a set of stochastic differential equations that incorporate the physics of velocity-dependent small-angle Coulomb collisions among the plasma particles in a particle-in-cell simulation. Each particle is scattered stochastically from all the other particles in a simulation cell modeled as one or more Maxwellians. Total energy and momentum are conserved by linear transformation of the velocity increments. In two test simulations the proposed “particle-moment” collision algorithm performs well with time steps as large as 10% of the relaxation time – far larger than a particle-pairing collision algorithm, in which pairs of particles are scattered from one another, requires to achieve the same accuracy. 相似文献
5.
Some new TO-phonon width data for Pb1?xSnxTe with strong temperature-dependence are explained in terms of a “modulation-effect” due to non-linear lattice modes. Reasonable values of the parameters provide very good agreement with the experimental widths. 相似文献
6.
DR.G. Domairry A. Mohsenzadeh M. Famouri 《Communications in Nonlinear Science & Numerical Simulation》2009,14(1):85-95
In this paper Jeffery–Hamel flow has been studied and its nonlinear ordinary differential equation has been solved through homotopy analysis method (HAM). The obtained solution in comparison with the numerical ones represents a remarkable accuracy. The results also indicate that HAM can provide us with a convenient way to control and adjust the convergence region. 相似文献
7.
Pearce JV Bossy J Schober H Glyde HR Daughton DR Mulders AN 《Physical review letters》2004,93(14):145303
Neutron scattering measurements of the fundamental excitations of liquid 4He confined in 44 A pore diameter gelsil glass at pressures up to 40 bars in the wave vector range 0.4
1.6 A(-1), especially the rotons, are observed up to complete solidification of all the liquid at a pressure of approximately 40 bars where the roton vanishes. At and above a pressure of 35.1 bars, Bragg peaks are observed, indicating coexistence of liquid and solid in the pores at pressures 35 less than or approximately equal P less than or approximately equal 40 bars. 相似文献
8.
Crystal Blake Kimberly M Fabick Kenneth DR Setchell Trent D Lund Edwin D Lephart 《BMC neuroscience》2011,12(1):28
Background
Soy-derived isoflavones potentially protect against obesity and depression. In five different studies we examined the influence of soy-containing diets or equol injections on depression, serotonin levels, body weight gain (BW) and white adipose tissue (WAT) deposition in female Long-Evans rats at various stages of life [rats were intact, ovariectomized or experienced natural ovarian failure (NOF)]. 相似文献9.
Linda Lee Samantha Daughton Steven Scheer Joseph C. Stemple Barbara Weinrich Tracy Miller-Seiler Scott Goeller Linda Levin 《Journal of voice》2003,17(3):411-424
Ten subjects with adductor spasmodic dysphonia participated in a study examining the effects of an acupuncture treatment protocol on their voice disorder. Treatment consisted of eight sessions, and it was designed and performed by two physicians certified in acupuncture. Voice characteristics were evaluated pretreatment and posttreatment using the CSL Motor Speech Profile (MSP), Unified Spasmodic Dysphonia Rating Scale, and Voice Handicap Index (VHI). Subjects also answered a posttreatment questionnaire regarding their experience. Significant pretreatment and posttreatment differences occurred for some MSP measures. Significant differences were found on all three subtests of the VHI, and the average total scores pretreatment and posttreatment differed by 17 points (considered significant according to VHI standardization). Seven of 10 subjects reported improvements in voice production, although expert raters did not detect perceptual changes in voice quality. Possible reasons for the discrepancies between objective measures and self ratings, and implications for further research, are discussed. 相似文献
10.
Emerging pollutants, and communicating the science of environmental chemistry and mass spectrometry: pharmaceuticals in the environment 总被引:7,自引:0,他引:7
Daughton CG 《Journal of the American Society for Mass Spectrometry》2001,12(10):1067-1076
While this paper is to a large degree targeted for those not familiar with mass spectrometry, [for an overview of mass spectrometry, a number of excellent websites are available, including http://base-peak.wiley.com/links/Resources/Educational_Resources/], the primary focus is on the importance of mass spectrometry in ultimately protecting public health and minimizing risks of chemical exposure. Its other audience is those who practice in this specialized field. Should this subject not interest you, by reading this article you can discover among other things, why elevator rides can be important for your career and for your discipline. Why acetaminophen is used for brown tree snakes, or lipid-lowering drugs for pigeons. 相似文献