No evidence of host specialization in a parasitic pea-crab exploiting two echinoid hosts

The pinnotherid crab Dissodactylus primitivus lives parasitically on 2 burrowingechinoid species, Meoma ventricosa and Plagiobrissus grandis. The fecundity of female crabsvaries between hosts, and is higher when parasitizing P. grandis than M. ventricosa. Moreover, thehosts present great variations in morphology (size and density of spines). These characteristicssuggest the potential to differentiate crabs according to host species. We investigated the genetic(microsatellites) and morphometric (outline analysis) differentiation of this parasitic crab between2 host species at 1 Jamaican site (Western Lagoon, Discovery Bay), and compared it with geographicdifferentiation among 4 sites along the north coast of Jamaica. Greater genetic differencesbetween parasites of the 2 sympatric hosts than between parasites of a single host at different geographiclocations would indicate host differentiation. Genetic analyses (microsatellites) did notdetect spatial differentiation (probably due to local hydrography) or differentiation according tohost species. This lack of host differentiation could be explained by mobility of adult crabsbetween hosts. However, there was weak but significant morphological differentiation betweenfemale crabs from the 2 hosts. This morphological difference may reflect constraints due to hostmorphology.

Atmospheric neutrino oscillation analysis with subleading effects in Super-Kamiokande I, II, and III

We present a search for nonzero θ13 and deviations of sin2θ23 from 0.5 in the oscillations of atmospheric neutrino data from Super-Kamiokande I, II, and III. No distortions of the neutrino flux consistent with nonzero θ13 are found and both neutrino mass hierarchy hypotheses are in agreement with the data. The data are best fit at Δm2=2.1×10-3eV2, sin2θ13=0.0, and sin2θ23=0.5. In the normal (inverted) hierarchy θ13 and Δm2 are constrained at the one-dimensional 90% C.L. to sin2θ13<0.04(0.09) and 1.9(1.7)×10 -3<Δm2<2.6(2.7)×10-3eV2. The atmospheric mixing angle is within 0.407≤sin2θ23≤0.583 at 90% C.L. © 2010 The American Physical Society.

Impact of the Interdecadal Pacific Oscillation on Tropical Cyclone Activity in the North Atlantic and Eastern North Pacific.

Tropical cyclones (TCs) are among the most devastating weather systems affecting the United States and Central America (USCA). Here we show that the Interdecadal Pacific Oscillation (IPO) strongly modulates TC activity over the North Atlantic (NA) and eastern North Pacific (eNP). During positive IPO phases, less (more) TCs were observed over NA (eNP), likely due to the presence of stronger (weaker) vertical wind shear and the resulting changes in genesis potential. Furthermore, TCs over NA tend to keep their tracks more eastward and recurve at lower latitudes during positive IPO phases. Such variations are largely determined by changes in steering flow instead of changes in genesis locations. Over the eNP, smaller track variations are observed at different IPO phases with stable, westward movements of TCs prevailing. These findings have substantial implications for understanding decadal to inter-decadal fluctuations in the risk of TC landfalls along USCA coasts.

The vague, the viral, the parasitic: Piranesi's metropolis

In mid-18th century Giovanni Battista Piranesi’s etchings systematically document the old and new monuments, decrepit buildings and broken down infrastructures of a Rome that continues to inhabit and reinvent its past. His views of Rome offer a devastating account of the blurring of distinctions and articulations that time, use and neglect have imposed on the old differentiations of the urban and the rural, the public and the private, the monumental and the domestic in the 18th century city. Rome becomes for Piranesi the laboratory for a questioning of architecture that places his work well beyond the debate on style and on the origin that dominated the architectural discourse of his time. This paper suggests that Piranesi’s images anticipate the dispersion and sprawl of the city of today, in which the ‘vague’, the ‘viral’ and the ‘parasitic’ become modes of inhabitation and of transient negotiated definition. In the Antichità di Roma, ancient buildings are represented not only in their large scale and magnificence, but also in their decay and reversal to a state of naturalness. These works, together with the acute observations of the Vedute di Roma, provide the materials that are then dislocated, manipulated, cloned and endlessly mutated by Piranesi in the synthesis of the Campo Marzio dell’Antica Roma, in which the historical city is almost entirely dissolved and replaced by an extraordinary congestion of fragments. When they are re-examined on the grounds of contemporary architectural and urban theory, the sites of Piranesi's views reveal anticipations of phenomena that affect the metropolis of today. Political, social and economic conditions have changed dramatically, but the questions asked of architecture in and by these sites challenge the definition of an architecture of style, forms and boundaries - in the 18th century as well as in the 21st -in favour of an architecture of change.

Morphological and molecular characteristics of a new species of Pasteuria parasitic on Meloidogyne ardenensis

A species of the hyper-parasitic bacterium Pasteuria was isolated from the root-knot nematode Meloidogyne ardenensis infecting the roots of ash (Fraxinus excelsior). It is morphologically different from some other Pasteuria pathogens of nematodes in that the spores lack a basal ring on the ventral side of the spore and have a unique clumping nature. Transmission electron microscopy (TEM) showed that the clumps of spores are not random aggregates but result from the disintegration of the suicide cells of the thalli. Sporulation within each vegetative mycelium was shown to be asynchronous. In addition to the novel morphological features 16S rRNA sequence analysis showed this to be a new species of Pasteuria which we have called P. hartismeri. Spores of P. hartismeri attach to juveniles of root-knot nematodes infecting a wide range of plants such as mint (Meloidogyne hapla), rye grass (unidentified Meloidogyne sp.) and potato (Meloidogyne fallax).

Ecological effects of the North Atlantic oscillation

Climatic oscillations as reflected in atmospheric modes such as the North Atlantic Oscillation (NAO) may be seen as a proxy for regulating forces in aquatic and terrestrial ecosystems. Our review highlights the variety of climate processes related to the NAO and the diversity in the type of ecological responses that different biological groups can display. Available evidence suggests that the NAO influences ecological dynamics in both marine and terrestrial systems, and its effects may be seen in variation at the individual, population and community levels. The ecological responses to the NAO encompass changes in timing of reproduction, population dynamics, abundance, spatial distribution and interspecific relationships such as competition and predator-prey relationships. This indicates that local responses to large-scale changes may be more subtle than previously suggested. We propose that the NAO effects may be classified as three types: direct, indirect and integrated. Such a classification will help the design and interpretation of analyses attempting to relate ecological changes to the NAO and, possibly, to climate in general.