The blue crab, Callinectes sapidus, is a keystone species which plays an integral ecological, economic, and sociological role in Chesapeake Bay. The blue crab functions as both predator and prey in the Bay’s complex estuarine foodweb and occupies a variety of critical habitats impacted by human activity. Blue crabs exhibit a complex life history, disperse between estuarine and marine habitats, ...

the family porcellanidae is a group of crab-shaped anomurans and there are a series of studies on this group in the persian gulf. the first report of porcellanid crabs from the persian gulf was by heller (1861); who referred incidentally to two species of this group in a discussion of crustacea of the red sea.

Creel surveys were performed over a three week period in late spring, 2011, in the Lafourche and Calcasieu area estuaries of the Louisiana Gulf Coast. Weights and lengths were measured for black drum (Pogonias cromis), red drum (Sciaenops ocellatus), and spotted seatrout (Cynoscion nebulosus), and relative condition factors were calculated relative to expected weights from the long term (5 year...

The recent Chandra image of the Crab nebula shows a striking, axisymmetric polar jet. It is shown that jets are formed in axisymmetric, magnetized pulsar winds and that the jet luminosity scales relative to the total as (γ0σeq) , where σeq is the ratio of Poynting flux to particle kinetic energy output at the equator at the base of the flow and γ0 the initial Lorentz factor of the flow. The res...

BACKGROUND Whereas testicular cancer incidence rates have been widely reported in populations of Northern European ancestry, rates in other populations have been less frequently examined. In a prior report, global testicular cancer incidence rates and trends for the years 1973 to 1997 were summarized. The current report extends these analyses with an additional 5 years of data from Cancer Incid...

The high energy experiment PDS is one of the Narrow Field Instruments aboard the X–ray astronomy satellite BeppoSAX . It covers the energy band from 15 to 300 keV. Here we report results on its in-flight performance and observations of galactic and extragalactic X–ray sources obtained during the Science Verification Phase of the satellite: in particular Crab, Cen X–3, 4U1626–67 and PKS2155–305.

The bacterial flora of blue crabs (Callinectes sapid us) from Chesapeake Bay was examined. Hemolymph of normal, healthy blue crabs was found non-sterile, with total bacterial counts ranging from <100 to >3.0 x 10 5 on a seawater-based medium and 0 to >10 5 on Standard Methods Agar. Counts of 0-10 3 were observed on TCBS agar. Vibrio spp., including Vibrio parahaemolyticus, were the major taxono...

Invasive species may precipitate evolutionary change in invaded communities. In southern New England (USA) the invasive Asian shore crab, Hemigrapsus sanguineus, preys on mussels (Mytlius edulis), but the crab has not yet invaded northern New England. We show that southern New England mussels express inducible shell thickening when exposed to waterborne cues from Hemigrapsus, whereas naïve nort...

Here we report a unique trophic interaction between the cryptogenic and sometimes highly toxic hydrozoan clinging jellyfish Gonionemus sp. and the spider crab Libinia dubia. We assessed species-specific predation on the Gonionemus medusae by crabs found in eelgrass meadows in Massachusetts, USA. The native spider crab species L. dubia consumed Gonionemus medusae, often enthusiastically, but the...

We analyze the stop-band due to crab cavities for horizontal tunes that are either close to integers or close to half integers. The latter case is relevant for today’s electron/positron colliders. We compare this stop-band to that created by dispersion in an accelerating cavity and show that a single typical crab cavity creates larger stop-bands than a typical dispersion at an accelerating cavi...