Evidence-based Tool for Triggering School Closures during Influenza Outbreaks, Japan

Guidelines available to school administrators to support school closure decisions during influenza outbreaks are usually not evidence-based. Using empirical data on absentee rates of elementary school students in Japan, we developed a simple and practical algorithm for determining the optimal timing of school closures for control of influenza outbreaks

Prospects for Spin Physics at RHIC

Colliding beams of 70% polarized protons at up to $\sqrt{s}$=500 GeV, with high luminosity, L=2$\times10^{{\rm 32}}$ cm$^{-2}$sec$^{-1}$, will represent a new and unique laboratory for studying the proton. RHIC-Spin will be the first polarized-proton collider and will be capable of copious production of jets, directly produced photons, and $W$ and $Z$ bosons. Features will include direct and precise measurements of the polarization of the gluons and of $\bar{u}$, $\bar{d}$, $u$, and $d$ quarks in a polarized proton. Parity violation searches for physics beyond the standard model will be competitive with unpolarized searches at the Fermilab Tevatron. Transverse spin will explore transversity for the first time, as well as quark-gluon correlations in the proton. Spin dependence of the total cross section and in the Coulomb nuclear interference region will be measured at collider energies for the first time. These qualitatively new measurements can be expected to deepen our understanding of the structure of matter and of the strong interaction.Comment: 51 pages, 22 figures. Scheduled to appear in the Annual Review of Nuclear and Particle Science Vol. 50, to be published in December 2000 by Annual Reviews, http://AnnualReviews.or

Geographic and Temporal Trends in Influenzalike Illness, Japan, 1992–1999

Kriging analysis improved visualization and understanding of trends in seasonal ILI activity in Japan

Chemodynamical Simulations of the Milky Way Galaxy

We present chemodynamical simulations of a Milky Way-type galaxy using a self-consistent hydrodynamical code that includes supernova feedback and chemical enrichment, and predict the spatial distribution of elements from Oxygen to Zinc. In the simulated galaxy, the kinematical and chemical properties of the bulge, disk, and halo are consistent with the observations. The bulge formed from the assembly of subgalaxies at z>3, and has higher [alpha/Fe] ratios because of the small contribution from Type Ia Supernovae. The disk formed with a constant star formation over 13 Gyr, and shows a decreasing trend of [alpha/Fe] and increasing trends of [(Na,Al,Cu,Mn)/Fe] against [Fe/H]. However, the thick disk stars tend to have higher [alpha/Fe] and lower [Mn/Fe] than thin disk stars. We also predict the frequency distribution of elemental abundance ratios as functions of time and location, which can be directly compared with galactic archeology projects such as HERMES.Comment: 43 pages, 20 figures, accepted to Ap

Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon

A search for new isotopes using in-flight fission of a 345 MeV/nucleon 238U beam has been carried out at the RI Beam Factory at the RIKEN Nishina Center. Fission fragments were analyzed and identified by using the superconducting in-flight separator BigRIPS. We observed 45 new neutron-rich isotopes: 71Mn, 73,74Fe, 76Co, 79Ni, 81,82Cu, 84,85Zn, 87Ga, 90Ge, 95Se, 98Br, 101Kr, 103Rb, 106,107Sr, 108,109Y, 111,112Zr, 114,115Nb, 115,116,117Mo, 119,120Tc, 121,122,123,124Ru, 123,124,125,126Rh, 127,128Pd, 133Cd, 138Sn, 140Sb, 143Te, 145I, 148Xe, and 152Ba

Study on Field Measurement and Ground Vibration for Superconducting Solenoid of New g-2 Experiment at J-PARC

Basic R&Ds of a superconducting solenoid for a new g-2 experiment at J-PARC are on going. High uniformity of magnetic field below 0.1 ppm is required for the g-2 experiment within a storage region of 33.3±5 cm in radius and ±10 cm in height. Two R&Ds have been started to develop the magnet with such high uniformity; a development of a precise field monitoring system and a study of seismic ground vibration. The prototype monitoring system using continuous wave type NMR probe for horizontal MRI solenoid has been built and tested. Cross-check between NMR and Hall probe has been also carried out. The seismic ground vibration has been measured at Materials and Life science Facility, MLF, in J-PARC. Based on the measured results, the spectrum analysis of the iron yoke has been performed using ANSYS