Molecular identification of Reesa vespulae (Milliron) (Coleoptera: Dermestidae), a newly recorded species from Korea

AbstractA museum pest belonging to the family Dermestidae was found in the Museum of Sunchon National University, Sunchon, Korea and identified using its morphological characteristics and a DNA-based analysis of the mitochondrial cytochrome c oxidase I (COI) gene. This marks the first recorded appearance of this pest, which is identified as Reesa vespulae (Milliron), in the Korean Peninsula. We provide the details of the morphological diagnosis with the habitus of its adult and larva and its COI barcode data, and introduce historical data about its invasion around the world

Soft x-ray polarizer for optical productions of any orthogonal state of the linear and circular polarization modes

An efficient soft x-ray polarizer that is able to optically convert a linear polarization state to any orthogonal state of not only linear but also circular polarization modes is found by means of numerical calculations of the intensities of individual orthogonal polarization components in reflected waves. Calculation results, using the known linear-polarization-mode based Kerr matrix as well as a newly derived circular-polarization-mode based Kerr matrix, indicate that a +45?? or -45?? linearly polarized incident wave can be readily converted to any orthogonal states of both circular and linear polarization modes, i.e., left- and right-handed circular and s - and p -linear polarizations through reflection, at certain grazing angles of incidence near the critical angle from a simple ferromagnetic thin film of Co (9.0 nm) Si substrate. The intensities of almost pure circularly or linearly polarized reflected waves are about 10% or less in a certain spectral soft x-ray range just below the absorption edges of constituent magnetic elements. The counterpart orthogonal states of the linear as well as circular modes can be rapidly switched simply by reversing oppositely the orientation of longitudinal magnetizations. These results suggest that the orthogonal polarization states of the circular- and linear-polarization modes converted from such a polarizing optical element through reflection can be practically used in probing the vector quantities of element specific magnetizations in multicomponent magnetic materials.open2

Depression research: where are we now?

Extensive studies have led to a variety of hypotheses for the molecular basis of depression and related mood disorders, but a definite pathogenic mechanism has yet to be defined. The monoamine hypothesis, in conjunction with the efficacy of antidepressants targeting monoamine systems, has long been the central topic of depression research. While it is widely embraced that the initiation of antidepressant efficacy may involve acute changes in monoamine systems, apparently, the focus of current research is moving toward molecular mechanisms that underlie long-lasting downstream changes in the brain after chronic antidepressant treatment, thereby reaching for a detailed view of the pathophysiology of depression and related mood disorders. In this minireview, we briefly summarize major themes in current approaches to understanding mood disorders focusing on molecular views of depression and antidepressant action

Nucleus accumbens shell moderates preference bias during voluntary choice behavior

The nucleus accumbens (NAc) shell lies anatomically at a critical intersection within the brain's reward system circuitry, however, its role in voluntary choice behavior remains unclear. Rats with electrolytic lesions in the NAc shell were tested in a novel foraging paradigm. Over a continuous two-week period they freely chose among four nutritionally identical but differently flavored food pellets by pressing corresponding levers. We examined the lesion's effects on three behavioral dynamics components: motivation (when to eat), preference bias (what to choose) and persistence (how long to repeat the same choice). The lesion led to a marked increase in the preference bias: i.e., increased selection of the most-preferred choice option, and decreased selection of the others. We found no effects on any other behavioral measures, suggesting no effect on motivation or choice persistence. The results implicate the NAc shell in moderating the instrumental valuation process by inhibiting excessive bias toward preferred choice options.11Ysciessciscopu

Oppositely rotating eigenmodes of spin-polarized current-driven vortex gyrotropic motions in elliptical nanodots

The authors found that there exist two different rotational eigenmodes of oppositely rotating sense in spin-polarized current-driven vortex gyrotropic motions in soft magnetic elliptical nanodots. Simple mathematical expressions were analytically calculated by adopting vortex-core (VC)-rotation-sense- dependent dynamic susceptibility tensors based on the linearized Thiele equation [Phys. Rev. Lett. 30, 230 (1973)]. The numerical calculations of those analytical expressions were confirmed by micromagnetic simulations, revealing that linear-regime steady-state VC motions driven by any polarized oscillating currents can be interpreted simply by the superposition of the clockwise and counterclockwise rotational eigenmodes. The shape of the orbital trajectories of the two eigenmodes is determined only by the lateral dimension of elliptical dots. Additionally, the orbital radii and phases of the two eigenmodes' VC motions were found to markedly vary with the frequency of applied currents, particularly across the vortex eigenfrequency and according to the vortex polarization, which results in overall VC motions driven by any polarized oscillating currents.open8

Reliability Analysis on Flexural Behavior of FRP Bridge Decks

Design codes for the design of FRP bridge decks shall be established to promote the use of such innovative materials. For the purpose of preparing code provisions, reliability analyses were conducted to evaluate proper levels of safety and serviceability. Based on the results, several guidelines on design codes are suggested

Origin, criterion, and mechanism of vortex-core reversals in soft magnetic nanodisks under perpendicular bias fields

We studied dynamics of vortex-core reversals driven by circular rotating fields along with static perpendicular magnetic fields of different direction and strength. We found that the application of perpendicular fields H p modifies the starting ground state of vortex magnetizations, thereby instigating the development of a magnetization dip mz,dip in the vicinity of the original core up to its threshold value, m z,dip cri ???-p, which is necessary for vortex-core reversals, where p is the initial core polarization. We found the relationship of the dynamic evolutions of the mz,dip and the out-of-plane gyrofields hz, which was induced, in this case, by vortex-core motion of velocity ??, thereby their critical value relation ??crihz cri. The simulation results indicated that the variation of the critical core velocity ??cri with Hp can be expressed explicitly as ??cri / ?? cri 0 = (??/ ??0) | -p- m z,dip g |, with the core size ?? and the starting ground-state magnetization dip m z,dip g variable with H p, and for the values of ?? cri 0 and ??0 at H p =0. This work offers deeper and/or new insights into the origin, criterion and mechanism of vortex-core reversals under application of static perpendicular bias fields.open7

Influence of mixed alkali oxides on some melt properties of TV screen glass

The influence of K2O/R2O (R2O = Na2O+K2O) on some melt properties was studied in alkali-alkaline earth-silicate TV screen glasses. Viscosity, surface tension, electrical resistivity, volatilization and devitrification of glass melts were determined. No mixed alkali effect was observed in viscosity, surface tension and liquidus temperature. They showed a linear behavior with increase of K2O/R2O. On the other hand, electrical resistivity and weight loss by volatilization showed a strong mixed alkali effect against relative alkali concentration. According to the dependence of viscosity, electrical resistivity and volatilization on K2O/R2O, the slope change of those properties took place at K2O/R2O = 0.4 to ≈ 0.5. The compositional dependence of viscosity, surface tension and liquidus temperature was discussed in terms of field strength, polarizability and material diffusion, respectively. Α correlation was also discussed between the dependence of properties on K2O/R2O and the production process of TV screen glass. In conclusion, from the viewpoint of both production and application of TV glasses it was suggested that the mole fraction of K2O/R2O should lie between 0.2 and 0.5

Two Circular-Rotational Eigenmodes in Vortex Gyrotropic Motions in Soft Magnetic Nanodots

We found, by micromagnetic numerical and analytical calculations, that the clockwise (CW) and counterclockwise (CCW) circular-rotational motions of a magnetic vortex core in a soft magnetic circular nanodot are the elementary eigenmodes existing in the gyrotropic motion with respect to the corresponding CW and CCW circular-rotational-field eigenbasis. Any steady-state vortex gyrotropic motions driven by a linearly polarized oscillating in-plane magnetic field in the linear regime can be perfectly understood according to the superposition of the two circular eigenmodes, which show asymmetric resonance characteristics reflecting the vortex polarization. The relative magnitudes in the amplitude and phase between the CCW and CW eigenmodes determine the elongation and orientation of the orbital trajectories of the vortex core motions, respectively, which trajectories vary with the polarization and chirality of the given vortex as well as the field frequency across the resonance frequency.Comment: 30 pages, 7 figure

Detecting axion dark matter with chiral magnetic effects

We show that dark matter axions or axion-like particles (ALP) induce non-dissipative alternating electric currents in conductors along the external magnetic fields due to the axial anomaly, realizing the chiral magnetic effects. We propose a new experiment to measure this current to detect the dark matter axions or ALP. This non-dissipative currents are the electron medium effects, directly proportional to the axion or ALP coupling to electrons, which depends on their microscopic physics.Comment: 11 pages, 3 figure