Surface damage resulting from rolling contact operating in magnetic field

This paper describes the effects of magnetic field in rolling contact tests of steel by using a two-disc configuration and the investigation of mechanisms involved. Two contact conditions, namely pure rolling and rolling with 10% sliding were used together with 0.4 and 1.1 Tesla horizontal static magnetic fields created by permanent magnets. Results of optical and scanning electron microscope observations point out that finer wear particles and smoother worn surfaces are produced in the presence of a magnetic field. It is proposed that finer wear particles result from the movement of subsurface crack initiation towards the surface due to the action of magnetic field

Development of displacement- and frequency-noise-free interferometer in 3-D configuration for gravitational wave detection

The displacement- and frequency-noise-free interferometer (DFI) is a multiple laser interferometer array for gravitational wave detection free from both the displacement noise of optics and laser frequency noise. So far, partial experimental demonstrations of DFI have been done in 2-D table top experiments. In this paper, we report the complete demonstration of a 3-D DFI. The DFI consists of four Mach-Zehnder interferometers with four mirrors and two beamsplitters. The displacement noises both of mirrors and beamsplitters were suppressed by up to 40 dB. The non-vanishing DFI response to a gravitational wave was successfully confirmed using multiple electro-optic modulators and computing methods

Asymptotically scale-invariant occupancy of phase space makes the entropy Sq extensive

Phase space can be constructed for $N$ equal and distinguishable subsystems that could be (probabilistically) either {\it weakly} (or {\it "locally"}) correlated (e.g., independent, i.e., uncorrelated), or {\it strongly} (or {\it globally}) correlated. If they are locally correlated, we expect the Boltzmann-Gibbs entropy $S_{BG} \equiv -k \sum_i p_i \ln p_i$ to be {\it extensive}, i.e., $S_{BG}(N)\propto N$ for $N \to\infty$. In particular, if they are independent, $S_{BG}$ is {\it strictly additive}, i.e., $S_{BG}(N)=N S_{BG}(1), \forall N$. However, if the subsystems are globally correlated, we expect, for a vast class of systems, the entropy $S_q\equiv k [1- \sum_i p_i^q]/(q-1)$ (with $S_1=S_{BG}$) for some special value of $q\ne1$ to be the one which extensive (i.e., $S_q(N)\propto N$ for $N \to\infty$).Comment: 15 pages, including 9 figures and 8 Tables. The new version is considerably enlarged with regard to the previous ones. New examples and new references have been include

Interspecific differences in the larval performance of Pieris butterflies (Lepidoptera: Pieridae) are associated with differences in the glucosinolate profiles of host plants

The tremendous diversity of plants and herbivores has arisen from a coevolutionary relationship characterized by plant defense and herbivore counter adaptation. Pierid butterfly species feed on Brassicales plants that produce glucosinolates as a chemical deterrent against herbivory. In turn, the larvae of pierids have nitrile specifier proteins (NSPs) that are expressed in their gut and disarm glucosinolates. Pierid butterflies are known to have diversified in response to glucosinolate diversification in Brassicales. Therefore, each pierid species is expected to have a spectrum of host plants characterized by specific glucosinolate profiles. In this study, we tested whether the larval performance of different Pieris species, a genus in Pieridae (Lepidoptera: Pieridae), was associated with plant defense traits of putative host plants. We conducted feeding assays using larvae of three Pieris species and 10 species of the Brassicaceae family possessing different leaf physical traits and glucosinolate profile measurements. The larvae of Pieris rapae responded differently in the feeding assays compared with the other two Pieris species. This difference was associated with differences in glucosinolate profiles but not with variations in physical traits of the host plants. This result suggests that individual Pieris species are adapted to a subset of glucosinolate profiles within the Brassicaceae. Our results support the idea that the host ranges of Pieris species depend on larval responses to glucosinolate diversification in the host species, supporting the hypothesis of coevolution between butterflies and host plants mediated by the chemical arms race

X-Ray Study of the Outer Region of Abell 2142 with Suzaku

We observed outer regions of a bright cluster of galaxies A2142 with Suzaku. Temperature and brightness structures were measured out to the virial radius ($r_{200}$) with good sensitivity. We confirmed the temperature drop from 9 keV around the cluster center to about 3.5 keV at $r_{200}$, with the density profile well approximated by the $\beta$ model with $\beta = 0.85$. Within 0.4\r_{200}, the entropy profile agrees with $r^{1.1}$, as predicted by the accretion shock model. The entropy slope becomes flatter in the outer region and negative around $r_{200}$. These features suggest that the intracluster medium in the outer region is out of thermal equilibrium. Since the relaxation timescale of electron-ion Coulomb collision is expected to be longer than the elapsed time after shock heating at $r_{200}$, one plausible reason of the low entropy is the low electron temperature compared to that of ions. Other possible explanations would be gas clumpiness, turbulence and bulk motions of ICM\@. We also searched for a warm-hot intergalactic medium around $r_{200}$ and set an upper limit on the oxygen line intensity. Assuming a line-of-sight depth of 2 Mpc and oxygen abundance of 0.1 solar, the upper limit of an overdensity is calculated to be 280 or 380, depending on the foreground assumption.Comment: 14 pages, 8 figure

Higgs condensation as an unwanted curvaton

During inflation in the early universe, the Higgs field continuously acquires long-wave quantum fluctuations. They accumulate to yield a non-vanishing value with an exponentially large correlation length. We study consequences of such Higgs condensations to show that, in inflation models where the universe is reheated through gravitational particle production at the transition to the kination regime, they not only contribute to reheat the universe but also act as a curvaton. Unfortunately, however, for parameters of the Standard Model Higgs field, this curvaton produces density fluctuations too large, so the inflation models followed by a long kination regime are ruled out.Comment: 13 pages; v2, layout adjusted, references adde