Analyses of silicon dioxide, magnesium oxide, lead fluoride, bismuth as low-pass velocity filters for neutrons

Transmission measurement of neutrons by filter materials for low energy neutrons is important for the study of structure and dynamics of condensed matter. Since only thermal neutrons are useful for such experiments, filter materials that transmit thermal neutrons while attenuating fast neutrons and gamma rays are of considerable interest

Comparative evaluation of twenty pilot workload assessment measure using a psychomotor task in a moving base aircraft simulator

A comparison of the sensitivity and intrusion of twenty pilot workload assessment techniques was conducted using a psychomotor loading task in a three degree of freedom moving base aircraft simulator. The twenty techniques included opinion measures, spare mental capacity measures, physiological measures, eye behavior measures, and primary task performance measures. The primary task was an instrument landing system (ILS) approach and landing. All measures were recorded between the outer marker and the middle marker on the approach. Three levels (low, medium, and high) of psychomotor load were obtained by the combined manipulation of windgust disturbance level and simulated aircraft pitch stability. Six instrument rated pilots participated in four seasons lasting approximately three hours each

Sifting through and sounding out : creative applications of sounds from the past - 300 word statement

The 1873 Comstock Act outlawed the production and distribution of any materials that were deemed to be obscene or capable of arousing adolescents. Mary Ware Dennett, a women\u27s rights activist and pioneer in birth control and sex education, was one of the many who fell victim to this law. Dennett was arrested in 1929 for distributing her sex education pamphlet, The Sex Side of Life, written for her teenage sons after finding the sex education materials produced by the government to be insufficient. This paper argues that Dennett\u27s pamphlet was scrutinized in United States v. Dennett because it emphasized not only the procreative and health aspects of sex, but also the emotional and physical pleasures of sex, which were topics that were avoided within the government\u27s work. This paper compares The Sex Side of Life to the government\u27s sex education materials from the early 1900s to provide insight into the inadequacies she found within them and to show the specific ways in which the content of her pamphlet differed from the work produced by the government

The Study of the Influence of Formulation and Process Variables on the properties of Simvastatin-Phospholipid Complex

Objectives: The aim of the present study was to examine the influence of the formulation and process variables on the entrapment efficiency of simvastatin-phospholipid complex (SPC), prepared with a goal of improving the solubility and permeability of simvastatin. Method: The SPC was prepared using a solvent evaporation method. The influence of formulation and process variables on simvastatin entrapment was assessed using a central composite design. An additional SPC was prepared using the optimized variables from the developed quadratic model. This formulation was characterized for its physical-chemical properties. The functional attributes of the optimized SPC formulation were analyzed by apparent aqueous solubility analysis, in-vitro dissolution studies, dissolution efficiency analysis, and ex-vivo permeability studies. Results: The factors studied were found to significantly influence on the entrapment efficiency. The developed model was validated using the optimized levels of formulation and process variables. The physical-chemical characterization confirmed a formation of the complex. The optimized SPC demonstrated over 25-fold higher aqueous solubility of simvastatin, compared to that of pure simvastatin. The optimized SPC exhibited a significantly higher rate and extent of simvastatin dissolution (\u3e98%), compared to that of pure simvastatin (∼16%). The calculated dissolution efficiency was also found to be significantly higher for the SPC (∼54 %), compared to that of pure simvastatin (∼8%). Finally, the optimized SPC exhibited a significantly higher simvastatin permeability (\u3e78%), compared to that of pure simvastatin (∼11%). Implications: The present study shows that simvastatin-phospholipid complex can be a promising strategy for improving the delivery of simvastatin, and similar drugs with low aqueous solubility

Study of the spectral properties of ELM precursors by means of wavelets

The high confinement regime (H-mode) in tokamaks is accompanied by the occurrence of bursts of MHD activity at the plasma edge, so-called edge localized modes (ELMs), lasting less than 1 ms. These modes are often preceded by coherent oscillations in the magnetic field, the ELM precursors, whose mode numbers along the toroidal and the poloidal directions can be measured from the phase shift between Mirnov pickup coils. When the ELM precursors have a lifetime shorter than a few milliseconds, their toroidal mode number and their nonlinear evolution before the ELM crash cannot be studied reliably with standard techniques based on Fourier analysis, since averaging in time is implicit in the computation of the Fourier coefficients. This work demonstrates significant advantages in studying spectral features of the short-lived ELM precursors by using Morlet wavelets. It is shown that the wavelet analysis is suitable for the identification of the toroidal mode numbers of ELM precursors with the shortest lifetime, as well as for studying their nonlinear evolution with a time resolution comparable to the acquisition rate of the Mirnov coils

Large-mode-number magnetohydrodynamic instability driven by sheared flows in a tokamak plasma with reversed central shear

The effect of a narrow sub-Alfvenic shear flow layer near the minimum q_min of the tokamak safety factor profile in a configuration with reversed central shear is analyzed. Sufficiently strong velocity shear gives rise to a broad spectrum of fast growing Kelvin-Helmholtz (KH)-like ideal magnetohydrodynamic (MHD) modes with dominant mode numbers m,n ~ 10. Nonlinear simulations with finite resistivity show magnetic reconnection near ripples caused by KH-like vortices, the formation of turbulent structures, and a flattening of the flow profile. The KH modes are compared to double tearing modes (DTM) which dominate at lower shearing rates. The possible application of these results in tokamaks with internal transport barrier is discussed.Comment: 4 pages, 4 figure