On the dynamical structure of the Trojan group of asteroids

Using a semi-analytical approach, domains of possible motion for Trojan asteroids were established. It is shown that stable librating motion is possible for both high inclination and high eccentricity. Frequency distributions were also produced for real Trojan asteroids, against differing libration amplitudes and libration periods

Large electroweak penguin contribution in B -> K pi and pi pi decay modes

We discuss about a possibility of large electroweak penguin contribution in B -> K pi and pi pi from recent experimental data. The experimental data may be suggesting that there are some discrepancies between the data and theoretical estimation in the branching ratios of them. In B -> K pi decays, to explain it, a large electroweak penguin contribution and large strong phase differences seem to be needed. The contributions should appear also in B -> pi pi. We show, as an example, a solution to solve the discrepancies in both B -> K pi and B -> pi pi. However the magnitude of the parameters and the strong phase estimated from experimental data are quite large compared with the theoretical estimations. It may be suggesting some new physics effects are including in these processes. We will have to discuss about the dependence of the new physics. To explain both modes at once, we may need large electroweak penguin contribution with new weak phases and some SU(3) breaking effects by new physics in both QCD and electroweak penguin type processes.Comment: 23 pages, 9 figure

Optical Levitation of a Droplet under Linear Increase of Gravitational Acceleration

Optical levitation of a liquid droplet in gas phase was investigated under timedependent change of the gravitational acceleration with specific flight pattern of an airplane. Through multiple trials under linear increase of effective gravitational acceleration, we performed the experiment of ptical trapping of a droplet from 0.3g_0 to 0.9g_0, where g_0 = 9.8 m/s^2. During such change of the effective gravitational acceleration, the trapping position on a droplet with the radius of 14 μm was found to be lowered by ca. 100 μm. The essential feature of the change of the trapping position is reproduced by a theoretical calculation under the framework of ray optics. As far as we know, the present study is the first report on optical levitation under time-dependent gravitational change

Toward the Stable Optical Trapping of a Droplet with Counter Laser Beams under Microgravity

To identify the optimum conditions for the optical trapping of a droplet under microgravity, we theoretically analyzed the efficiency of trapping with counter laser beams. We found that the distance between the two foci is an important parameter for obtaining stable trapping conditions. We also performed an optical trapping experiment with counter laser beams under microgravity. The experimental results correspond well to the theoretical prediction

A Solution for Little Hierarchy Problem and b --> s gamma

We show that all the parameters which destabilize the weak scale can be taken around the weak scale in the MSSM without conflicting with the SM Higgs mass bound set by LEP experiment. The essential point is that if the lightest CP-even Higgs h in the MSSM has only a small coupling to Z boson, g_{ZZh}, LEP cannot generate the Higgs sufficiently. In the scenario, the SM Higgs mass bound constrains the mass of the heaviest CP-even Higgs H which has the SM like g_{ZZH} coupling. However, it is easier to make the heaviest Higgs heavy by the effect of off-diagonal elements of the mass matrix of the CP-even Higgs because the larger eigenvalue of 2 times 2 matrix becomes larger by introducing off-diagonal elements. Thus, the smaller stop masses can be consistent with the LEP constraints. Moreover, the two excesses observed at LEP Higgs search can naturally be explained as the signals of the MSSM Higgs h and H in this scenario. One of the most interesting results in the scenario is that all the Higgs in the MSSM have the weak scale masses. For example, the charged Higgs mass should be around 130 GeV. This looks inconsistent with the lower bound obtained by the b --> s gamma process as m_{H^\pm}>350GeV. However, we show that the amplitude induced by the charged Higgs can naturally be compensated by that of the chargino if we take the mass parameters by which the little hierarchy problem can be solved. The point is that the both amplitudes have the same order of magnitudes when all the fields in the both loops have the same order of masses.Comment: 14 pages, 5 figures, input parameter slightly changed, figures replaced, references correcte

Discrete Klein-Gordon models with static kinks free of the Peierls-Nabarro potential

For the nonlinear Klein-Gordon type models, we describe a general method of discretization in which the static kink can be placed anywhere with respect to the lattice. These discrete models are therefore free of the {\it static} Peierls-Nabarro potential. Previously reported models of this type are shown to belong to a wider class of models derived by means of the proposed method. A relevant physical consequence of our findings is the existence of a wide class of discrete Klein-Gordon models where slow kinks {\it practically} do not experience the action of the Peierls-Nabarro potential. Such kinks are not trapped by the lattice and they can be accelerated by even weak external fields.Comment: 6 pages, 2 figure

Efficient and Rapid Analysis of Polysomes and Ribosomal Subunits in Cells and Tissues Using Ribo Mega-SEC

Polysome profile analysis is a popular method for separating polysomes and ribosomal subunits and is typically achieved using a sucrose density gradient (SDG). This has remained the gold standard method since ribosomes were first discovered; however, this method is time-consuming and requires multiple steps from making the gradient and long ultracentrifugation to collecting and analyzing the fractions. Each of these steps in the SDG workflow can introduce potential technical variation that affects the reproducibility of gradient profiles between samples. To address these limitations, we have developed a flexible, alternative approach for analyzing polysomes and ribosomal subunits based on size-exclusion chromatography (SEC), termed ‘Ribo Mega-SEC.’ In comparison with the SDG method, Ribo Mega-SEC involves a single step using ultra-high-performance liquid chromatography (uHPLC). The entire workflow, from injecting the lysate to collecting the fractions, can be performed in as little as 15 min, with high reproducibility. By varying the pore size of the SEC column, polysomes and ribosomal subunits can be separated using extracts from either human or mouse cultured cell lines or from tissue samples, Drosophila embryos, or budding yeast. The resulting separated fractions are suitable for analysis using a wide range of subsequent analytical techniques including mass spectrometry (MS)-based proteomics, RNA-Seq, electron microscopy (EM), and multiple biochemical assays

Conjunction study of plasmapause location using ground‐based magnetometers, IMAGE‐EUV, and Kaguya‐TEX data

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94992/1/jgra20214.pd

Local structures of polar wurtzites Zn_{1-x}Mg_{x}O studied by Raman and {67}Zn/{25}Mg NMR spectroscopies and by total neutron scattering

Local compositions and structures of Zn_{1-x}Mg_{x}O alloys have been investigated by Raman and solid-state {67}Zn/{25}Mg nuclear magnetic resonance (NMR) spectroscopies, and by neutron pair-distribution-function (PDF) analyses. The E2(low) and E2(high) Raman modes of Zn_{1-x}Mg_{x}O display Gaussian- and Lorentzian-type profiles, respectively. At higher Mg substitutions, both modes become broader, while their peak positions shift in opposite directions. The evolution of Raman spectra from Zn_{1-x}Mg_{x}O solid solutions are discussed in terms of lattice deformation associated with the distinct coordination preferences of Zn and Mg. Solid-state magic-angle-spinning (MAS) NMR studies suggest that the local electronic environments of {67}Zn in ZnO are only weakly modified by the 15% substitution of Mg for Zn. {25}Mg MAS spectra of Zn_{0.85}Mg_{0.15}O show an unusual upfield shift, demonstrating the prominent shielding ability of Zn in the nearby oxidic coordination sphere. Neutron PDF analyses of Zn_{0.875}Mg_{0.125}O using a 2x2x1 supercell corresponding to Zn_{7}MgO_{8} suggest that the mean local geometry of MgO_{4} fragments concurs with previous density functional theory (DFT)-based structural relaxations of hexagonal wurtzite MgO. MgO_{4} tetrahedra are markedly compressed along their c-axes and are smaller in volume than ZnO_{4} units by ~6%. Mg atoms in Zn_{1-x}Mg_{x}O have a shorter bond to the $c$-axial oxygen atom than to the three lateral oxygen atoms, which is distinct from the coordination of Zn. The precise structure, both local and average, of Zn_{0.875}Mg_{0.125}O obtained from time-of-flight total neutron scattering supports the view that Mg-substitution in ZnO results in increased total spontaneous polarization.Comment: 12 pages, 14 figures, 2 table