Tracing the Dynamics of Disk Galaxies with Optical and IR Surface Photometry: Color Gradients in M99

We present optical and IR surface photometry of M99 (NGC 4254) at g, r_S i, J and K'. We also present a K' image of M51 (NGC 5194) for comparison. Fourier decomposition of the disk light reveals that the radial distribution of power depends on wavelength, which in turn implies that the spiral structure traced in the visual (i.e. young population I and dust) is different from the one detected at 2 microns (i.e. old stellar disk). We observe radial modulation of the power and a dependency of power with wavelength that are consistent with modal theory of spiral structure. A central motivation for our research is the fundamental idea of density wave theory that the passage of a spiral density wave triggers star formation. We have found a stellar population age gradient consistent with this scenario in a reddening-free, red supergiant-sensitive, Q-like photometric parameter at 6 kpc galactocentric distance across one of the arms of M99. We rule out that the change in this parameter, Q(r_SJgi), across the arm is mainly due to dust. The difference in Q(r_SJgi) going from the interarm regions to the arms also indicates that arms cannot be due exclusively to crowding of stellar orbits. We present the first measurement of Omega_p, the angular speed of the spiral pattern, and of the location of the corotation radius, derived from the drift velocity of the young stars away from their birth site. The measured Q(r_SJgi) implies a star formation rate for M99 within the range of 10-20 M_odot/yr; a disk stellar mass surface density of ~80 M_odot/pc^2; and a maximum contribution of ~20 percent from red supergiants to the K' light in a small region, and much smaller on average. We measure a K' arm--interarm contrast of 2-3, too high for M99 to be a truly isolated galaxy.Comment: 25 pages of uuencoded, compressed Postscript (text only). To appear in 1 April 1996 issue of The Astrophysical Journal. Also available, together with 2 uuencoded, compressed PostScript files with 10 figures each, at http://astro.berkeley.edu/preprints.htm

Russian manufacturing and the threat of ‘Dutch disease’: a comparison of competitiveness developments in Russian and Ukrainian industry

This paper examines the development of Russian industry in comparison with that of Ukrainian industry during 1995–2004 in an effort to ascertain to what extent, if any, Russian manufacturing showed signs of succumbing to ‘Dutch disease’. Ukraine and Russia began the market transition with broadly similar institutions, industrial structures and levels of technology, and the economic reforms implemented in the two countries were also similar, although Ukraine was reckoned to lag behind Russia in many areas. The main difference between them is Russia’s far greater resource wealth. It follows that differences in industrial development since 1991 may to some degree be attributable to differences in initial natural resource endowments. In short, Ukraine could provide a rough approximation of how a resource-poor Russia might have developed over the transition

An alternative singularity-free cosmological scenario from cusp geometries

We study an alternative geometrical approach on the problem of classical cosmological singularity. It is based on a generalized function $f (x, y) = x^{2} + y^{2} = (1 - z)z^{n}$ which consists of a cusped coupled isosurface. Such a geometry is computed and discussed into the context of Friedmann singularity-free cosmology where a pre-big bang scenario is considered. Assuming that the mechanism of cusp formation is described by non-linear oscillations of a pre-big bang extended very high energy density field ($> 3 \times 10^{94} kg/m^{3}$), we show that the action under the gravitational field follows a tautochrone of revolution, understood here as the primary projected geometry that alternatively replaces the Friedmann singularity in the standard big bang theory. As shown here this new approach allows us to interpret the nature of both matter and dark energy from first geometric principles.Comment: Proceedings of Sixth International School on Field Theory and Gravitation-2012 - by American Institute of Physic

Estimation of the methane emission factor for the Italian Mediterranean buffalo

In order to contribute to the improvement of the national greenhouse gas emission inventory, this work aimed at estimating a country-specific enteric methane (CH4) emission factor for the Italian Mediterranean buffalo. For this purpose, national agriculture statistics, and information on animal production and farming conditions were analysed, and the emission factor was estimated using the Tier 2 model of the Intergovernmental Panel on Climate Change. Country-specific CH4 emission factors for buffalo cows (630 kg body weight, BW) and other buffalo (313 kg BW) categories were estimated for the period 1990–2004. In 2004, the estimated enteric CH4 emission factor for the buffalo cows was 73 kg/head per year, whereas that for other buffalo categories it was 56 kg/head per year. Research in order to determine specific CH4 conversion rates at the predominant production system is suggested

Inorganic separator for a high temperature silver-zinc battery

Electrode design, inorganic separators, and performance tests of multiplate five ampere-hour silver-zinc battery cel