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The effects of two-color light on stimulated Brillouin scattering (SBS) in an inhomogeneous flowing plasma have been investigated. The three-wave match of SBS is satisfied at multiple spatial locations and the multiple resonance regions occur when the two-color laser incident on an inhomogeneous flowing plasma, leading to multiple scattering of scattered light, which results in an enhancement of the reflectivity of the laser rather than a significant decrease. If the distance between the resonance points is smaller than the resonance length of SBS, the ion acoustic waves generated at different locations are coupled to each other, which enhances SBS. A model of multiple regions resonance of SBS is presented, and a one-dimensional Vlasov–Maxwell code is employed to verify the enhancement. [ABSTRACT FROM AUTHOR]

A hypothesis of the electrostatic field for the expansion of a plasma composed of two ion species into a vacuum is proposed. The solution for expansion is derived analytically and verified by numerical simulations. The expansion region is predicted to exhibit a constant velocity difference between the two ion components, which could result in ion beam instability and, thus, an increase in ion temperature. The instability, which occurs in CH plasma, is also verified theoretically and examined by particle-in-cell simulations. [ABSTRACT FROM AUTHOR]

The influence of alloying elements on the stacking fault energy (SFE) of magnesium alloys containing long period stacking ordered (LPSO) structure was studied systematically by means of first-principles calculation. The element features and criterion of formation of LPSO in Mg-RE-X system was discussed, when X = Zn, Cu, Ag and Cu, and RE = Gd, Dy, Ho, Er and La. It was found that stacking faults played a crucial role in formation of LPSO structure. The influence of SFE should be considered into the element features and criterion of the formation of LPSO. The element features and criterion of formation of LPSO in Mg-RE-X system were suggested to be modified as follows: the element RE and X can decrease the SFE of magnesium alloys and the algebraic expression for the sum of chemical misfit of RE and chemical misfit of X was negative with a bigger numerical value. The present results were helpful for further investigation on strengthening-toughening of magnesium alloys for LPSO was found to increase the strength and toughness of magnesium alloys effectively. [ABSTRACT FROM AUTHOR]

Objective To assess effects of desvenlafaxine (administered as desvenlafaxine succinate) on secondary outcomes of mood, climacteric symptoms, and treatment satisfaction in postmenopausal women with moderate to severe menopausal vasomotor symptoms (VMS). Methods A 12-week, multicenter, double-blind, placebo-controlled trial was conducted in postmenopausal women with ≥ 50 moderate to severe hot flushes per week. Participants were randomly assigned to desvenlafaxine 100 mg/day, desvenlafaxine 150 mg/day, or placebo. Secondary outcome efficacy variables included Profile of Mood States (POMS), Greene Climacteric Scale (GCS), and Menopausal Symptoms Treatment Satisfaction Questionnaire (MS-TSQ) scores. Change from baseline in POMS total mood disturbance (TMD) score and subdomain scores were evaluated using analysis of covariance, adjusting for treatment and study site as factors and baseline score. GCS total and subdomain scores were analyzed similarly. Treatment satisfaction was analyzed using the row mean score test. Results A total of 458 women were enrolled. At week 12, desvenlafaxine 100 mg/day significantly improved POMS TMD scores (p< 0.001) and four of six POMS subdomains compared with placebo (all p ≤ 0.005). Women taking desvenlafaxine 100 mg/day experienced significantly greater improvement in GCS total scores (p< 0.001) and five of six subdomains (all p≤ 0.029) compared with placebo. Treatment with desvenlafaxine 100 mg/day resulted in significantly greater treatment satisfaction overall and in six of seven additional MS-TSQ items (all p ≤ 0.042). Desvenlafaxine 150-mg/day results were similar. Conclusions Desvenlafaxine treatment improved mood and climacteric symptoms in postmenopausal women with moderate to severe VMS compared with placebo, and more women were satisfied with desvenlafaxine treatment than with placebo. [ABSTRACT FROM AUTHOR]

Objective To evaluate the efficacy and safety of desvenlafaxine (administered as desvenlafaxine succinate) vs. tibolone and placebo for menopausal vasomotor symptoms and the incidence of uterine bleeding. Methods This 12-week, double-blind, randomized, controlled trial was conducted at 35 sites in Europe, two sites in South Africa, and one site in Mexico. Postmenopausal women with ≥50 moderate or severe hot flushes per week ( n == 485) were randomized to desvenlafaxine 100 mg/day, tibolone 2.5 mg/day, or placebo. Reduction in the average daily number of moderate and severe hot flushes at weeks 4 and 12 (primary endpoint) was evaluated using analysis of covariance. Safety assessments included incidence of uterine bleeding, adverse events, laboratory values, and vital signs. Results At week 12, no statistically significant difference was observed in reduction of the average daily number of moderate and severe hot flushes for desvenlafaxine (−5.78) vs. placebo (−5.82; p == 0.921), although time to 50% reduction was significantly less than placebo (13 vs. 26 days, p == 0.006). Hot flush reduction with tibolone (−8.21) was significantly greater than placebo ( p < 0.001). Nausea was the most common adverse event with desvenlafaxine, was generally mild to moderate, and resolved within the first 2 weeks. Significantly more subjects experienced bleeding with tibolone (23%) vs. desvenlafaxine (12%; p < 0.024) or placebo (9%; p < 0.001). Conclusions Desvenlafaxine did not separate from placebo in reducing the number of moderate to severe hot flushes at week 12, although it did allow women to achieve 50% reduction sooner than placebo. Tibolone did separate from placebo, but with smaller than expected effect. The placebo effect was high (57%). Adverse drug reactions were consistent with the known safety profile of desvenlafaxine, and significantly more women who received tibolone experienced episodes of bleeding compared with women who received desvenlafaxine or placebo. [ABSTRACT FROM AUTHOR]

The effects of TiC additions on the as cast and heat treated microstructures and mechanical properties of ZA84 Mg alloy are investigated. The results indicate that, after adding 0·5 wt-%TiC to ZA84 alloy, the as cast microstructure of the alloy is refined. At the same time, the distribution of second phases in the alloy becomes relatively uniform and the quasi-continuous networked second phases in the alloy become discontinuous. As a result, the as cast tensile properties of the alloy are improved. In addition, after solutionisation at 345°C, parts of the Mg32(Al,Zn)49 phases in the ZA84 alloy without TiC modification still exhibit quasi-continuous distribution. The Mg32(Al,Zn)49 phases in the ZA84 alloy treated with 0·5 wt-%TiC change to disconnected particles with an angular morphology and gradually spheroidise. Under the optimum heat treated conditions, the ZA84 alloy treated with 0·5 wt-%TiC exhibits higher heat treated tensile properties than the ZA84 alloy without TiC modification. [ABSTRACT FROM AUTHOR]

In the present paper, the effects of treating processes on the microstructure of commercial Al–10Sr master alloy and its refinement efficiency to AZ31 magnesium alloy are investigated. The results indicate that the solution heat treatment, rolling and remelting have significant effects on the morphology and/or size of Al4Sr phase in the commercial Al–10Sr master alloy. After being solutionised at 773 K for 4 h and followed by water quenching, the Al4Sr phases evolve from coarse blocks to relatively fine blocks. However, after being rolled at 573 K for a total reduction level of 50% or remelted and followed by rapid cooling, the Al4Sr phases respectively exhibit fine particles or fibre shapes. In addition, after the commercial Al–10Sr master alloy is solutionised, rolled or remelted, its refinement efficiency to AZ31 alloy is improved, and the improvement resulting from the remelting is the most significant, the next is rolling and solutionisation respectively. [ABSTRACT FROM AUTHOR]

We present a staged hot-electron acceleration mechanism of the two-plasmon decay (TPD) instability in the transverse magnetic field under the parameters relevant to inertial confinement fusion experiments. After being accelerated by the forward electron plasma wave (FEPW) of TPD, the hot-electrons can be anomalously accelerated again by the backward electron plasma wave (BEPW) of TPD and then obtain higher energy. Moreover, the surfatron acceleration mechanism of TPD in the magnetic field is also confirmed, the electrons trapped by the TPD daughter EPWs are accelerated in the direction along the wave front. Interestingly, the velocity of electrons accelerated by surfing from the FEPW is quite easily close to the BEPW phase velocity, which markedly enhances the efficiency of the staged acceleration. The coexistence of these two acceleration mechanisms leads to a significant increase of energetic electrons generated by TPD in the magnetic field. Meanwhile the EPWs are dissipated, TPD instability is effectively suppressed, and the laser transmission increases.

A kinetic theory is developed to describe the longitudinal decay of two-ion decay (TID): The pump ion-acoustic wave (IAW) decays into two daughter IAWs with a longer wavelength. The instability growth rate and threshold are given by the theory. Both the simulations of full kinetic Vlasov and hybrid Vlasov (kinetic ions and Boltzmann electrons) are employed to verify the theory and have a high quantitative agreement with the theory for 8≤ZT&#95;{e}/T&#95;{i}≤15, where Z is the ion charge number and T&#95;{i}(T&#95;{e}) is the ion (electron) temperature. The kinetic model developed here solves a long-standing problem that the simple fluid theory underestimates growth rate by a factor of 2∼3. Also, a reasonable explanation is given to the typical characteristics of TID that the dependence curves of subharmonic growth rate γ and wave number k.

The ejection of microdroplets from the surface of a freezing supercooled water drop has been observed and photographed. The fragmentation of a freezing drop in the forms of splintering, shattering, or bursting has been known for some time. This newly observed phenomenon of the ejection of numerous microdroplets, the duration of their ejection, and the electrical properties of these droplets suggest a possible mechanism of charge generation in thunderstorms.