Correlation Statistics of Irregular and Spiral Galaxies Mapped in HI

Several measures of galaxy size and mass obtained from the neutral hydrogen mapping of 70 dwarf irregular galaxies presented in Paper I (Hoffman et al. 1996) are compared statistically to those for the set of all available HI-mapped dwarfs and HI-mapped spirals distributed within the same spatial volume to investigate variations in Tully-Fisher relations and in surface densities as functions of galaxy size and luminosity or mass. Some ambiguities due to the ``non-commutativity'' of the correlations among the variables are addressed and linear regressions of logarithms of blue luminosity, HI and optical radii, velocity profile half-width incorporating rotation and random motions, HI mass, and indicative dynamical mass are presented and analyzed. The surface density of HI is almost constant along the sequence of size/mass/luminosity while surface density of blue luminosity increases with galaxy size. For quantities not involving HI we find no evidence for a ``break'' between dwarfs and spirals, but we do find some curvature in velocity vs. radius and in the Tully-Fisher relation. There is an indication for a difference in the correlations involving HI mass or radius between dwarfs alone and spirals alone, in the sense that irregulars have somewhat more HI mass or slightly larger HI radii than spirals at a given blue luminosity, optical radius, or velocity profile width.Comment: AASTeX, to appear in ApJ, 26 pages + 3 tables + 12 figure

\u3ci\u3eArgulus\u3c/i\u3e, a Branchiuran Parasite of Freshwater Fishes

Fish lice of the genus Argulus (suborder Branchiura) are Common parasites of freshwater fish, and may occur on frogs and salamanders. Argulids often cause severe mortality of fish in farm ponds, and sometimes in natural waters. Because information on life cycles, ecology, and host specificity is incomplete only a generalized account can be given

A vector error correction forecasting model of the U.S. economy

Any research or policy analysis in economics must be consistent with the time-series properties of observed macroeconomic data. Numerous previous studies of such time series reinforce the need to specify correctly a model's multivariate stochastic structure. This paper discusses in detail the speciation of a vector error correction forecasting model that is anchored by long-run equilibrium relationships suggested by economic theory. The model includes six variables - the CPI, the implicit price deflator for GDP, real money balances (MI), the federal funds rate, the yield on long-term (10-year) government bonds, and real GDP - and four cointegrating vectors. Model forecasts during the 1990's are compared to those made by the Federal Reserve and by private forecasters.Forecasting ; Econometric models

Development of a cobalt-tungsten ferromagnetic, high-temperature, structural alloy

Cobalt-tungsten ferromagnetic, high temperature structural alloy for rotor applications in space power generator

A low-loss photonic silica nanofiber for higher-order modes

Optical nanofibers confine light to subwavelength scales, and are of interest for the design, integration, and interconnection of nanophotonic devices. Here we demonstrate high transmission (> 97%) of the first family of excited modes through a 350 nm radius fiber, by appropriate choice of the fiber and precise control of the taper geometry. We can design the nanofibers so that these modes propagate with most of their energy outside the waist region. We also present an optical setup for selectively launching these modes with less than 1% fundamental mode contamination. Our experimental results are in good agreement with simulations of the propagation. Multimode optical nanofibers expand the photonic toolbox, and may aid in the realization of a fully integrated nanoscale device for communication science, laser science or other sensing applications.Comment: 12 pages, 5 figures, movies available onlin

What does the future hold for utility electricity efficiency programs?

This study develops projections of future spending and savings from electricity efficiency programs funded by electric utility customers in the United States through 2030 based on three scenarios. Our analysis relies on detailed bottom-up modeling of current state energy efficiency policies, demand-side management and integrated resource plans, and regulatory decisions. The three scenarios represent a range of potential outcomes given the policy environment at the time of the study and uncertainties in the broader economic and state policy environment in each state. We project spending to increase to $8.6 billion in 2030 in the medium scenario, about a 45 percent increase relative to 2016 spending. In the high case, annual spending increases to$11.1 billion in 2030 and remains relatively flat in the low case ($6.8 billion in 2030). Our analysis suggests that electricity efficiency programs funded by utility customers will continue to impact load growth significantly at least through 2030, as savings as a percent of retail sales are forecast at 0.7 percent in the medium scenario and 0.98 percent in the high scenario