Toxic dinoflagellates and marine mammal mortalities : proceedings of an expert consultation held at the Woods Hole Oceanographic Institution

On May 8 and 9, 1989, a consultation of experts was convened at the Woods Hole Oceanographic Institution to discuss the possible link between natural biotoxins and recent mass mortalities of humpback whales and bottlenose dolphins along the eastern coast of the United States. The focus was on the possible role of dinoflagellate toxins in these events. The objectives of the meeting were to review and assess the existing evidence and to recommend research priorities and needs.Funding was provided by NOAA, National Marine Fisheries Service, Woods Hole Oceanographic Institution Coastal Research Center through a grant from the Andrew W. Mellon Foundation and the Woods Hole Oceanographic Institution Sea Grant Program under Grant NA86-D-SW90 (Project R/B - 92 and M/O-2)

Wright: Comparative Conflict Resolution Procedures in Taxation

A Review of Comparative Conflict Resolution Procedures in Taxation edited by L. Hart Wrigh

Estimated annual economic impacts from harmful algal blooms (HABs) in the United States

Blooms of toxic or harmful microalgae, commonly called "red tides," represent a significant and expanding threat to human health and fisheries resources throughout the United States and the world. Ecological, aesthetic, and public health impacts include: mass mortalities of wild and farmed fish and shellfish, human intoxication and death from the consumption of contaminated shellfish or fish, alterations of marine food webs through adverse effects on larvae and other life history stages of commercial fish species, the noxious smell and appearance of algae accumulated in nearshore waters or deposited on beaches, and mass mortalities of marine mammals, seabirds, and other animals. In this report, we provide an estimate of the economic impacts of HABs in the United States from events where such impacts were measurable with a fair degree of confidence during the interval 1987-92. The total economic impact averaged $49 million per year, with public health impacts representing the largest component (45 percent). Commercial fisheries impacts were the next largest (37 percent of the total), while recreation/tourism accounted for 13 percent, and monitoring/management impacts 4 percent. These estimates are highly conservative, as many economic costs or impacts from HABs could not be estimated.Funding was provided by the National Oceanic and Atmospheric Administration under Grants No. NA46RG0470 and NA90AA-D-SG480, the National Science Foundation under Grant No. OCE-9321244, and the Johnson Endowment of the Marine Policy Center

Guidelines for Permitting Overloads, Part 2: Statistical Analysis of Overload Vehicle Effects on Indiana Highway Bridges

This report summarizes an analytical investigation carried out to develop a set of guidelines for regulation of overload vehicles in Indiana. A formula based first phase evaluation of overload permit requests is developed through statistical study of the rating of a representative sample of the highway bridges in Indiana using a representative sample of overload vehicles observed in the state in 1990 and 1991 plus the HS 20 design vehicle and the two Indiana Toll Road loadings. A sample of 148 bridges is chosen from a total population of 3700 Indiana highway bridges using a proportionate stratified random sampling process. A sample of 25 trucks, with the truck parameters uniformly distributed over their ranges is compiled from the 1990 and 1991 truck population (permit vehicles obtained from INDOT and AASHTO HS Design Vehicle). The selected trucks are used to rate bridges in the selected sample using the Bridge Analysis and Rating System (BARS) program at the operating stress level. BARS is based on elastic line girder and truss analysis. The allowable load, W, is subjected to linear regression analysis with several bridge and truck parameters as regressor or independent variables

Field relations, age, and tectonic setting of metamorphic and plutonic rocks in the Creignish Hills – North Mountain area, southwestern Cape Breton Island, Nova Scotia, Canada

 The Creignish Hills and North Mountain areas of southwestern Cape Breton Island consist mostly of Neoproterozoic rocks typical of the Ganderian Bras d’Or terrane. U-Pb ages presented here for detrital zircon in the Blues Brook Formation of the Creignish Hills confirm a depositional age no greater than about 600 Ma. Although it is possible that some components of the formation are much older, similarities in rock types and field relations suggest that this is not the case. It is likely that the equivalent Malagawatch Formation of the North Mountain area, as well as high-grade metasedimentary rocks of the Melford Formation and Chuggin Road complex in the Creignish Hills and Lime Hill gneiss complex in the North Mountain area, represent the same or stratigraphically equivalent units as the Blues Brook Formation. The minimum ages of all of these units are constrained by cross-cutting syn- and post-tectonic plutons with ages mostly between 565 and 550 Ma, indicating that sediments were deposited, regionally metamorphosed, deformed, and intruded by plutons in less than 40–50 million years. The assemblage of pelitic, psammitic, and carbonate rocks indicates that a passive margin in a tropical climate was quickly changed to an active Andean-type continental margin in which voluminous calcalkaline dioritic to granitic plutons were emplaced. This sedimentary and tectonic history is characteristic of the Bras d’Or terrane and is shared by its likely correlative, the Brookville terrane in southern New Brunswick.

The z=5 Quasar Luminosity Function from SDSS Stripe 82

We present a measurement of the Type I quasar luminosity function at z=5 using a large sample of spectroscopically confirmed quasars selected from optical imaging data. We measure the bright end (M_1450<-26) with Sloan Digital Sky Survey (SDSS) data covering ~6000 deg^2, then extend to lower luminosities (M_1450<-24) with newly discovered, faint z~5 quasars selected from 235 deg^2 of deep, coadded imaging in the SDSS Stripe 82 region (the celestial equator in the Southern Galactic Cap). The faint sample includes 14 quasars with spectra obtained as ancillary science targets in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), and 59 quasars observed at the MMT and Magellan telescopes. We construct a well-defined sample of 4.7<z<5.1 quasars that is highly complete, with 73 spectroscopic identifications out of 92 candidates. Our color selection method is also highly efficient: of the 73 spectra obtained, 71 are high redshift quasars. These observations reach below the break in the luminosity function (M_1450* ~ -27). The bright end slope is steep (beta <~ -4), with a constraint of beta < -3.1 at 95% confidence. The break luminosity appears to evolve strongly at high redshift, providing an explanation for the flattening of the bright end slope reported previously. We find a factor of ~2 greater decrease in the number density of luminous quasars (M_1450<-26) from z=5 to z=6 than from z=4 to z=5, suggesting a more rapid decline in quasar activity at high redshift than found in previous surveys. Our model for the quasar luminosity function predicts that quasars generate ~30% of the ionizing photons required to keep the universe ionized at z=5.Comment: 29 pages, 22 figures, ApJ accepted (updated to published version

Changes in the Expression of Human Cell Division Autoantigen-1 Influence Toxoplasma gondii Growth and Development

Toxoplasma is a significant opportunistic pathogen in AIDS, and bradyzoite differentiation is the critical step in the pathogenesis of chronic infection. Bradyzoite development has an apparent tropism for cells and tissues of the central nervous system, suggesting the need for a specific molecular environment in the host cell, but it is unknown whether this environment is parasite directed or the result of molecular features specific to the host cell itself. We have determined that a trisubstituted pyrrole acts directly on human and murine host cells to slow tachyzoite replication and induce bradyzoite-specific gene expression in type II and III strain parasites but not type I strains. New mRNA synthesis in the host cell was required and indicates that novel host transcripts encode signals that were able to induce parasite development. We have applied multivariate microarray analyses to identify and correlate host gene expression with specific parasite phenotypes. Human cell division autoantigen-1 (CDA1) was identified in this analysis, and small interfering RNA knockdown of this gene demonstrated that CDA1 expression causes the inhibition of parasite replication that leads subsequently to the induction of bradyzoite differentiation. Overexpression of CDA1 alone was able to slow parasite growth and induce the expression of bradyzoite-specific proteins, and thus these results demonstrate that changes in host cell transcription can directly influence the molecular environment to enable bradyzoite development. Investigation of host biochemical pathways with respect to variation in strain type response will help provide an understanding of the link(s) between the molecular environment in the host cell and parasite development

The clustering of massive galaxies at z~0.5 from the first semester of BOSS data

We calculate the real- and redshift-space clustering of massive galaxies at z~0.5 using the first semester of data by the Baryon Oscillation Spectroscopic Survey (BOSS). We study the correlation functions of a sample of 44,000 massive galaxies in the redshift range 0.4<z<0.7. We present a halo-occupation distribution modeling of the clustering results and discuss the implications for the manner in which massive galaxies at z~0.5 occupy dark matter halos. The majority of our galaxies are central galaxies living in halos of mass 10^{13}Msun/h, but 10% are satellites living in halos 10 times more massive. These results are broadly in agreement with earlier investigations of massive galaxies at z~0.5. The inferred large-scale bias (b~2) and relatively high number density (nbar=3e-4 h^3 Mpc^{-3}) imply that BOSS galaxies are excellent tracers of large-scale structure, suggesting BOSS will enable a wide range of investigations on the distance scale, the growth of large-scale structure, massive galaxy evolution and other topics.Comment: 11 pages, 12 figures, matches version accepted by Ap