Oscillating Coulomb chain in a storage ring

The dynamic behavior of a bunched one-dimensional crystalline beam is studied theoretically. It is shown that, owing to the existence of momentum dispersion, a Coulomb chain traveling in a storage ring performs a complex periodic oscillation whenever it is exposed to a longitudinal radio-frequency force. The equations of motion are derived to predict the oscillation pattern in an arbitrary lattice structure. The validity of the present theory is confirmed through multiparticle simulations. Various features of an oscillating string beam, such as the lattice-parameter dependence of the orbit, the stability, and critical line density, etc., are also discussed

A Monofilar Spiral Antenna Excited Through a Helical Wire

The radiation characteristics of a monofilar spiral antenna excited through a helical wire are investigated using the method of moments. The spiral has a circumference of more than two wavelengths (2.3λ6, where λ6 is the wavelength at a test frequency of 6 GHz) to obtain a tilted beam. An input impedance of approximately 50 Ω is realized by appropriately selecting the diameter and pitch angle of the helical wire. The antenna shows a gain of approximately 8 dB relative to an isotropic source in the maximum beam direction (18° from the direction normal to the antenna plane) and a VSWR frequency bandwidth of approximately 12%

Tilted- and axial-beam formation by a single-arm rectangular spiral antenna with compact dielectric substrate and conducting plane

A single-arm rectangular spiral antenna is analyzed using the finite-difference time-domain method. The spiral is printed on a finite-size dielectric substrate backed by a finite-size conducting plane. Both the substrate and conducting planes are square with a side length L of less than 0.6λ0 (λ0: wavelength in free space). The radiation pattern is dependent on the outermost arm peripheral length C. The spiral whose peripheral length is within 2λg<C<3λg (λg: the guided wavelength of the current) radiates a tilted beam of circular polarization. When the peripheral length is decreased to λg<C<2λg, the spiral radiates an axial beam. The axial beam has a wide half-power beam width of approximately 102° (for L&ap;0.369λ0) with a gain of approximately 6.7 dB. The axial beam shows a 15% frequency bandwidth for a 3 dB axial ratio criterion. Over this bandwidth, the voltage standing-wave ratio (VSWR) is less than two, as desired. The experimental results for the radiation pattern, gain, axial ratio, and VSWR are also presented

β-Glucan Derived from Aureobasidium pullulans Is Effective for the Prevention of Influenza in Mice

β-(1→3)-D-glucans with β-(1→6)-glycosidic linked branches produced by mushrooms, yeast and fungi are known to be an immune activation agent, and are used in anti-cancer drugs or health-promoting foods. In this report, we demonstrate that oral administration of Aureobasidium pullulans-cultured fluid (AP-CF) enriched with the β-(1→3),(1→6)-D-glucan exhibits efficacy to protect mice infected with a lethal titer of the A/Puerto Rico/8/34 (PR8; H1N1) strain of influenza virus. The survival rate of the mice significantly increased by AP-CF administration after sublethal infection of PR8 virus. The virus titer in the mouse lung homogenates was significantly decreased by AP-CF administration. No significant difference in the mRNA expression of inflammatory cytokines, and in the population of lymphocytes was observed in the lungs of mice administered with AP-CF. Interestingly, expression level for the mRNA of virus sensors, RIG-I (retinoic acid-inducible gene-I) and MDA5 (melanoma differentiation-associated protein 5) strongly increased at 5 hours after the stimulation of A. pullulans-produced purified β-(1→3),(1→6)-D-glucan (AP-BG) in murine macrophage-derived RAW264.7 cells. Furthermore, the replication of PR8 virus was significantly repressed by pre-treatment of AP-BG. These findings suggest the increased expression of virus sensors is effective for the prevention of influenza by the inhibition of viral replication with the administration of AP-CF

Bankruptcy is an inevitable fate of repeated investments with leverage

Due to the globalization and computerization of financial and economic activities, numerous repetitive leveraged investments have become possible in stock markets and currency exchanges. In reality, repeated leveraged investments up to 100 times/day are possible via online access. With computer-aided programs, this repetition number may easily increase 1000 times/day. The possibility of bankruptcy in repeated leveraged investments has never been considered in actual practices because the probability of bankruptcy in a single investment trial is almost negligible. Here, we show that the extremely numerous repetitions have a considerable chance of bankruptcy overall, even if the probability of bankruptcy for a single investment is extremely close to zero. The exact relationship between the repetitions and the probability of bankruptcy is approximated well by n(0.63)?=?m, where 10n is the number of repetitions, 10-m is the bankruptcy probability of a single investment, and n(0.63) is the 63% chance of bankruptcy. Thus, extremely rare events can always lead to bankruptcy in continuously repeated investment, even if the possibility of such an event is almost null. We suggest that the avoidance measure of bankruptcy is necessary in numerous repeated investments even if a single trial is almost certain to win