Records of Zygopa michaelis Holthuis, 1960 (Decapoda: Anomura: Albuneidae) from the Gulf of Mexico

The albuneid mole crab, Zygopa michaelis Holthuis, 1960, which was originally described from Curaçao and recently reported from the Florida East coast (Gore and Becker 1977), is reported from the Gulf of Mexico off the Florida West coast. Of the seven specimens collected, six were taken in 38 m of water off Fort Myers and one in 42 m on the Florida Middle Ground. All seven specimens occurred in substrata composed primarily of carcareous sand

Mass Vaccination Campaign Following Community Outbreak of Meningococcal Disease

During December 12–29, 1998, seven patients ages 2–18 years were diagnosed with serogroup C meningococcal disease in two neighboring Florida towns with 33,000 residents. We evaluated a mass vaccination campaign implemented to control the outbreak. We maintained vaccination logs and recorded the resources used in the campaign that targeted 2- to 22-year-old residents of the two towns. A total of 13,148 persons received the vaccinations in 3 days. Vaccination coverage in the target population was estimated to be 86% to 99%. Five additional cases of serogroup C meningococcal disease occurred in the community during the year after the campaign began, four in patients who had not received the vaccine. The cost of control efforts was approximately $370,000. Although cases continued to occur, the vaccination campaign appeared to control the outbreak. Rapid implementation, a targeted approach, and high coverage were important to the campaign's success

Observational Evidence for the Co-evolution of Galaxy Mergers, Quasars, and the Blue/Red Galaxy Transition

We compile a number of observations to estimate the time-averaged rate of formation or buildup of red sequence galaxies, as a function of mass and redshift. Comparing this with the mass functions of mergers and quasar hosts, and independently comparing their clustering properties as a function of redshift, we find that these populations trace the same mass distribution, with similar evolution, at redshifts 0<z<~1.5. Knowing one of the quasar, merger, or elliptical mass/luminosity functions, it is possible to predict the others. Allowing for greater model dependence, we compare the rate of early-type buildup with the implied merger and quasar triggering rates as a function of mass and redshift and find agreement. Over this redshift range, observed merger fractions can account for the entire bright quasar luminosity function and buildup of the red sequence at all but the highest masses at low redshift (>~10^11 M_solar at z<~0.3) where 'dry' mergers appear to dominate. This supports a necessary prediction of theories where mergers between gas-rich galaxies produce ellipticals with an associated phase of quasar activity, after which the remnant becomes red. These populations trace a similar characteristic transition mass, possibly reflecting the mass above which the elliptical population is mostly (>~50%) assembled at a given redshift, which increases with redshift over the observed range in a manner consistent with suggestions that cosmic downsizing may apply to red galaxy assembly as well as star formation. These mass distributions as a function of redshift do not uniformly trace the all/red/blue galaxy population, ruling out models in which quasar activity is generically associated with star formation or is long lived in 'old' systems.Comment: 24 pages, 17 figures. Accepted to ApJ. Substantially revised and expanded to match published versio

Mass of the Southern Black Hole in NGC 6240 from Laser Guide Star Adaptive Optics

NGC 6240 is a pair of colliding disk galaxies, each with a black hole in its core. We have used laser guide star adaptive optics on the Keck II telescope to obtain high-resolution ($\sim 0.06$") near-infrared integral-field spectra of the region surrounding the supermassive black hole in the south nucleus of this galaxy merger. We use the K-band CO absorption bandheads to trace stellar kinematics. We obtain a spatial resolution of about 20 pc and thus directly resolve the sphere of gravitational influence of the massive black hole. We explore two different methods to measure the black hole mass. Using a Jeans Axisymmetric Multi-Gaussian mass model, we investigate the limit that a relaxed mass distribution produces all of the measured velocity dispersion, and find an upper limit on the black hole mass at 2.0 \pm 0.2 \times 10^9 M_{\sun}. When assuming the young stars whose spectra we observe remain in a thin disk, we compare Keplerian velocity fields to the measured two-dimensional velocity field measured and fit for a mass profile containing a black hole point mass plus a radially-varying spherical component, which suggests a lower limit for the black hole mass of 8.7 \pm 0.3 \times 10^8 M_{\sun}. Our measurements of the stellar velocity dispersion place this AGN within the scatter of the $M_{BH}$-$\sigma_{*}$ relation. As NGC 6240 is a merging system, this may indicate that the relation is preserved during a merger at least until the final coalescence of the two nuclei.Comment: 10 pages, 12 figures; accepted to Ap

PHSkb: A knowledgebase to support notifiable disease surveillance

BACKGROUND: Notifiable disease surveillance in the United States is predominantly a passive process that is often limited by poor timeliness and low sensitivity. Interoperable tools are needed that interact more seamlessly with existing clinical and laboratory data to improve notifiable disease surveillance. DESCRIPTION: The Public Health Surveillance Knowledgebase (PHSkb™) is a computer database designed to provide quick, easy access to domain knowledge regarding notifiable diseases and conditions in the United States. The database was developed using Protégé ontology and knowledgebase editing software. Data regarding the notifiable disease domain were collected via a comprehensive review of state health department websites and integrated with other information used to support the National Notifiable Diseases Surveillance System (NNDSS). Domain concepts were harmonized, wherever possible, to existing vocabulary standards. The knowledgebase can be used: 1) as the basis for a controlled vocabulary of reportable conditions needed for data aggregation in public health surveillance systems; 2) to provide queriable domain knowledge for public health surveillance partners; 3) to facilitate more automated case detection and surveillance decision support as a reusable component in an architecture for intelligent clinical, laboratory, and public health surveillance information systems. CONCLUSIONS: The PHSkb provides an extensible, interoperable system architecture component to support notifiable disease surveillance. Further development and testing of this resource is needed

Active Galactic Nuclei and the Truncation of Star Formation in K+A Galaxies

We have searched for active galactic nuclei (AGNs) in K+A galaxies, using multiwavelength imaging and spectroscopy in the Bootes field of the NOAO Deep Wide-Field Survey. The K+A galaxies, which have had their star formation rapidly truncated, are selected via their strong Balmer absorption lines and weak H-alpha emission. Our sample consists of 24 K+A galaxies selected from 6594 0.10<z<0.35 galaxies brighter than I=20 with optical spectroscopy from the AGN and Galaxy Evolution Survey. Two thirds of the K+A galaxies are likely ongoing galaxy mergers, with nearby companion galaxies or tidal tails. Galaxy mergers may be responsible for the truncation of star formation, or we are observing the aftermath of merger triggered starbursts. As expected, the optical colors of K+A galaxies largely fall between blue galaxies with ongoing star formation and red passive galaxies. However, only 1% of the galaxies with colors between the red and blue populations are K+A galaxies, and we conclude that the truncation of star formation in K+A galaxies must have been unusually abrupt (<100 Myr). We examined the AGN content of K+A galaxies with both optical emission-line ratios (BPT diagrams) and Chandra X-ray imaging. At least half of all K+A galaxies display the optical emission-line ratios of AGNs, and a third of M_R<-22 K+A galaxies host AGNs with X-ray luminosities of 10^{42} erg/s. The faintest K+A galaxies do not show clear evidence for hosting AGNs, having emission-line ratios consistent with photoionization by massive stars and few X-ray detections. We speculate that two mechanisms may be responsible for the truncation of star formation in K+A galaxies, with AGN feedback only playing a role in M_R<-20.5 galaxies.Comment: Accepted for publication in the Astrophysical Journal. 13 pages, 8 figure

Connecting the Gamma Ray Burst Rate and the Cosmic Star Formation History: Implications for Reionization and Galaxy Evolution

(Abridged) The contemporary discoveries of galaxies and gamma ray bursts (GRBs) at high redshift have supplied the first direct information on star formation when the universe was only a few hundred million years old. The probable origin of long duration GRBs in the deaths of massive stars would link the universal GRB rate to the redshift-dependent star formation rate density, although exactly how is currently unknown. As the most distant GRBs and star-forming galaxies probe the reionization epoch, the potential rewards of understanding the redshift-dependent ratio Psi(z) of the GRB rate to star formation rate are significant and include addressing fundamental questions such as incompleteness in rest-frame UV surveys for determining the star formation rate at high redshift and time variations in the stellar initial mass function. Using an extensive sample of 112 GRBs above a fixed luminosity limit drawn from the Second Swift Burst Alert Telescope catalog, we compare the cumulative redshift distribution N(< z) of GRBs with the star formation density rho_sfr(z) measured from UV-selected galaxies over 0 < z < 4. Strong evolution (e.g., Psi(z) \propto (1+z)^{1.5}) is disfavored, while more modest evolution (e.g., Psi(z) \propto (1+z)^{0.5}) is consistent with the data. If such trends continue beyond z ~ 4, we find the discovery rate of distant GRBs implies a star formation rate density much higher than that inferred from UV-selected galaxies. We show that such a star formation history would over-predict the observed stellar mass density at z > 4 measured from rest-frame optical surveys. The resolution of this important disagreement is currently unclear, and the GRB production rate at early times is likely more complex than a simple function of star formation rate and progenitor metallicity.Comment: Version accepted by Ap

Influence of blade aerodynamic model on the prediction of helicopter high-frequency airloads

Brown’s vorticity transport model has been used to investigate the influence of the blade aerodynamic model on the accuracy with which the high-frequency airloads associated with helicopter blade–vortex interactions can be predicted. The model yields an accurate representation of the wake structure yet allows significant flexibility in the way that the blade loading can be represented. A simple lifting-line model and a somewhat more sophisticated liftingchord model, based on unsteady thin aerofoil theory, are compared. A marked improvement in the accuracy of the predicted high-frequency airloads of the higher harmonic control aeroacoustic rotor is obtained when the liftingchord model is used instead of the lifting-line approach, and the quality of the prediction is affected less by the computational resolution of the wake. The lifting-line model overpredicts the amplitude of the lift response to blade–vortex interactions as the computational grid is refined, exposing the fundamental deficiencies in this approach when modeling the aerodynamic response of the blade to interactions with vortices that are much smaller than its chord. The airloads that are predicted using the lifting-chord model are relatively insensitive to the resolution of the computation, and there are fundamental reasons to believe that properly converged numerical solutions may be attainable using this approach