Fiducial Stellar Population Sequences for the u'g'r'i'z' System

We describe an extensive observational project that has obtained high-quality and homogeneous photometry for a number of different Galactic star clusters (including M 92, M 13, M 3, M 71, and NGC 6791) spanning a wide range in metallicity (-2.3<[Fe/H]<+0.4), as observed in the u'g'r'i'z' passbands with the MegaCam wide-field imager on the Canada-France-Hawaii Telescope. By employing these purest of stellar populations, fiducial sequences have been defined from color-magnitude diagrams that extend from the tip of the red-giant branch down to approximately 4 magnitudes below the turnoff: these sequences have been accurately calibrated to the standard u'g'r'i'z' system via a set of secondary photometric standards located within these same clusters. Consequently, they can serve as a valuable set of empirical fiducials for the interpretation of stellar populations data in the u'g'r'i'z' system.Comment: 16 pages, 7 tables, 13 figures; accepted for publication in A

On board sampling of the rockfish and lingcod commerical passenger fishing vessel industry in northern and central California, May 1987 to December 1991

From May 1987 to June 1990 and from August to December 1991 Fishery Technicians sampled catches on board 690 Commercial Passenger Fishing Vessel (CPFV) trips targeting rockfish and lingcod from the general port areas of Fort Bragg, Bodega Bay, San Francisco, Monterey, and Morro Bay. Data are presented for species composition by port area, year, and month, for catch-per-unit-effort, mean length, and length frequency of lingcod and the 18 most frequently observed rockfish species, and for trends in fishing effort related to fishing time, depth, and distance from port. Total catch estimates are presented based on unadjusted logbook records, logbook records adjusted by sampling data and compliance rates, and effort data from a marine recreational fishing statistics survey. Average catch of kept fish per angler day was 11.8 and average catch of kept fish per angler hour was 3.7. A trend of an increasing frequency of trips to deep (>40 fm) locations was observed in the Bodega Bay, San Francisco, and Monterey areas from 1988 to 1990-91. No trend was evident relative to trip frequency and distance from port. A total of 74 species was observed caught during the study. Rockfishes comprised 88.5% to 97.9% by number of the observed catch by port area. The five most frequently observed species were chilipepper, blue, yellowtail, and widow rockfishes, and bocaccio, with lingcod ranking seventh. In general, mean length and catch-per-angler-hour of sport fishes caught by CPFV anglers varied considerably and did not show steady declines during the study period. However, port-specific areas of major concern were identified for chilipepper, lingcod, and black rockfish, and to a lesser extent brown, canary, vermilion, yelloweye, olive, and widow rockfish. These areas of concern included steadily declining catch rate, steadily declining mean length, and a high percentage of sexually immature fish in the sampled-catch. Recent sampling of the commercial hook-and-line fishery in northern and central California indicated that most species of rockfishes taken by CPFV anglers are also harvested commercially. (261pp.

Bright Variable Stars in NGC 6819 - An Open Cluster in the Kepler Field

We describe a variability study of the moderately old open cluster NGC 6819. We have detected 4 new detached eclipsing binaries near the cluster turnoff (one of which may be in a triple system). Several of these systems should be able to provide mass and radius information, and can therefore constrain the age of the cluster. We have also newly detected one possible detached binary member about 3.5 magnitudes below the turnoff. One EW-type binary (probably not a cluster member) shows unusually strong night-to-night light curve variations in sets of observations separated by 8 years. According to the best current information, the three brightest variables we detected (2 of them new) are cluster members, making them blue stragglers. One is a delta Scu pulsating variable, one is a close but detached binary, and the third contains a detached short period binary that shows total eclipses. In each case, however, there is evidence hinting that the system may have been produced through the interaction of more than two stars.Comment: 33 pages, 15 figures, accepted to A

Evaluation of an epigenetic assay for predicting repeat prostate biopsy outcome in African American men

OBJECTIVE: To evaluate an epigenetic assay performed on tissue from negative prostate biopsies in a group of African American (AA) men undergoing repeat biopsy, and to compare accuracy for predicting repeat biopsy outcome to prior studies conducted in predominantly Caucasian populations. MATERIALS AND METHODS: The study population consisted of 211 AA men from 7 urology centers across the United States; all of whom were undergoing 12-core transrectal ultrasound-guided repeat biopsy within 30 months from a negative index biopsy. All biopsy cores from the negative index biopsy were profiled for the epigenetic biomarkers GSTP1, APC, and RASSF1 using ConfirmMDx for Prostate Cancer (MDxHealth, Irvine, CA). RESULTS: Upon repeat biopsy, 130 of 211 subjects (62%) had no prostate cancer (PCa) detected and 81 of 211 (38%) were diagnosed with PCa. Of the subjects with PCa, 54 (67%) were diagnosed with Gleason score (GS) = 7 disease. For detection of PCa at repeat biopsy, ConfirmMDx sensitivity was 74.1% and specificity was 60.0%, equivalent to prior studies (P = .235 and .697, respectively). For detection of GS >= 7 PCa, sensitivity was 78% and specificity was 53%. The negative predictive values for detection of all PCa and GS >= 7 PCa were 78.8% and 94.2%, respectively. CONCLUSION: In this group of AA men, we successfully validated an epigenetic assay to assess the need for repeat biopsy. Results were consistent with previous studies from predominantly Caucasian populations. Therefore, the ConfirmMDx assay is a useful tool for risk stratification of AA men who had an initial negative biopsy

A Stochastic Analysis of Pumping Tests in Laterally Nonuniform Media

This is the published version. Copyright American Geophysical UnionConventional pumping test analysis methodology assumes that aquifer transmissivity is invariant in space. The ramifications of this assumption are examined for hypothetical units whose variations in transmissivity are considered to be reasonable representations of variations possible in natural systems. The dependence of pumping test transmissivity on spatial (angular and radial) and temporal location of observations and the method of drawdown analysis is assessed. The dependence on the angular position of an observation well appears of little significance. Dependence on radial position, however, can be strong. The dependence on the interval of time used in the pumping test analysis is only important in highly variable systems. Methods of drawdown analysis that yield identical estimates in uniform units yield differing estimates in nonuniform ones as a result of a difference in data-fitting procedures. A reasonable estimate of transmissivity at a regional scale can be obtained from a Cooper-Jacob analysis applied at a large duration of pumpage. In general, conventional approaches for pumping test analysis should be viable in the nonuniform aquifers of the type considered here

Abundances in giant stars of the globular cluster NGC 6752

Recent theoretical yields and chemical evolution models demonstrate that intermediate-mass AGB stars cannot reproduce the observed abundance distributions of O, Na, Mg, and Al. As a further observational test of this finding, we present elemental abundance ratios [X/Fe] for 20 elements in 38 bright giants of the globular cluster NGC 6752. Our mean abundance ratios [X/Fe] are in good agreement with previous studies of this cluster and are also consistent with other globular clusters and field stars at the same metallicity. The mean abundance ratios [Ba/Eu] and [La/Eu] exhibit values, in agreement with field stars at the same metallicity, that lie approximately midway between the pure r-process and the solar (s-process + r-process) mix, indicating that AGB stars have played a role in the chemical evolution of the proto-cluster gas. For the first time, we find possible evidence for an abundance variation for elements heavier than Al in this cluster. We find a correlation between [Si/Fe] and [Al/Fe] which is consistent with the abundance anomalies being synthesized via proton captures at high temperatures. Leakage from the Mg-Al chain into 28Si may explain the Si excess in stars with the highest [Al/Fe]. We identify correlations between [Y/Fe] and [Al/Fe], [Zr/Fe] and [Al/Fe], and [Ba/Fe] and [Al/Fe] suggesting that Y, Zr, and Ba abundances may increase by about 0.1 dex as Al increases by about 1.3 dex. While the correlations are statistically significant, the amplitudes of the variations are small. If the small variations in Y, Zr, and Ba are indeed real, then the synthesis of the Al anomalies must have taken place within an unknown class of stars that also ran the s-process. [Abridged]Comment: Accepted for publication in A&