The genus <i>Batzella</i>: a chemosystematic problem

Biogenetically unrelated cyclic guanidine alkaloids and pyrroloquinoline alkaloids have been reported from sponges assigned to the genus Batzella. These sponges have been assigned to this genus because of their possession of a simple complement of thin strongyles in irregular plumoreticulate arrangement. Cyclic guanidine alkaloids were first reported from an alleged axinellid species from the Caribbean, Ptilocaulis aff. P. spiculifer, and subsequently from a second Carribean specimen identified as Ptilocaulis spiculifer and at the same time from a Red Sea poecilosclerid, Hemimycale sp. Closely related compounds were described from a Caribbean specimen identified as Batzella sp. and also from the poecilosclerids Crambe crambe (Mediterranean) and Monanchora arbuscula (Brazil). Isobatzellins (pyrroloquinoline alkaloids) were reported from a black deep-water species from the Bahamas identified as Batzella sp. Chemically related pyrroloquinoline alkaloids were found in Pacific representatives of the fistular poecilosclerid genus Zyzzya, the hadromerid genus Latrunculia and the ?haplosclerid genus Prianos. Most of the voucher specimens involved in this puzzle were re-examined and several conclusions can be drawn: when inspected closely it appears, that the cyclic guanidine alkaloids are produced by sponges containing anisostrongyles, often in two categories, a thicker and a thinner one. Monanchora arbuscula, which has been recently discovered to produce these compounds, has monactinal spicules differentiated into a thinner subtylostyle and a thicker (tylo-) style, but many specimens have anisostrongylote modifications. Microscleres in Monanchora can be absent or very rare. By association, all the sponges from which cyclic guanidine alkaloids are known may be united in one family, possibly in a single wider defined genus Monanchora. However, further relationships with Crambe need to be studied. Both have cyclic guanidine alkaloids, both have megascleres of very variable shapes and thickness, differentiated mostly into two overlapping categories, microscleres and other additional spicules are often rare or absent. Relationships with the type of Hemimycale, viz. H. columella remain obscure, but in view of the much larger spicules of that species and the intricate ectosomal specialization (lacking in the above mentioned specimens) it is possible that similarities between the Red Sea Hemimycale and the European species are the product of parallel evolution. The strongyles of sponges producing pyrroloquinoline alkaloids are perfect isostrongyles and in the ectosome these are arranged in a definite ectosomal tangential crust. A good proportion of these strongyles have a faint spination on the apices. Assignment of these sponges to Batzella rest on the properties of its type species Batzella inops. Examination of a type spicule slide of that species did not solve that question, but until further notice Batzella may be used for the deep-water material. A further unsolved problem that remains is the phylogenetic relationships of Batzella with Zyzzya and Latrunculia. The likelyhoods of possible causes for this distribution of compounds are discussed

Acute gastrointestinal illness in two Inuit communities : burden of illness in Rigolet and Iqaluit, Canada : author version

Results of this study highlight the need for systematic data collection to better understand and support previously anecdotal indications of high acute gastrointestinal illness (AGI) incidence. Cross-sectional retrospective surveys captured information on AGI and potential environmental risk factors. Lack of access to health services can result in reduced care-seeking behaviour, which can compromise the quality and quantity of available surveillance data. The aim of the research was to estimate the incidence and prevalence of AGI, and to identify potential socio-economic and environmental risk factors in the Inuit communities of Rigolet, Nunatsiavut and Iqaluit in Nunavut, Canada

Continental-scale geographic change across zealandia during paleogene subduction initiation

Data from International Ocean Discovery Program (IODP) Expedition 371 reveal vertical movements of 1-3 km in northern Zealandia during early Cenozoic subduction initiation in the western Pacific Ocean. Lord Howe Rise rose from deep (~1 km) water to sea level and subsided back, with peak uplift at 50 Ma in the north and between 41 and 32 Ma in the south. The New Caledonia Trough subsided 2-3 km between 55 and 45 Ma. We suggest these elevation changes resulted from crust delamination and mantle flow that led to slab formation. We propose a "subduction resurrection" model in which (1) a subduction rupture event activated lithospheric-scale faults across a broad region during less than ~5 m.y., and (2) tectonic forces evolved over a further 4-8 m.y. as subducted slabs grew in size and drove plate-motion change. Such a subduction rupture event may have involved nucleation and lateral propagation of slip-weakening rupture along an interconnected set of preexisting weaknesses adjacent to density anomalies

Global Search for New Physics with 2.0/fb at CDF

Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak-scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with the standard model prediction. A model-independent approach (Vista) considers gross features of the data, and is sensitive to new large cross-section physics. Further sensitivity to new physics is provided by two additional algorithms: a Bump Hunter searches invariant mass distributions for "bumps" that could indicate resonant production of new particles; and the Sleuth procedure scans for data excesses at large summed transverse momentum. This combined global search for new physics in 2.0/fb of ppbar collisions at sqrt(s)=1.96 TeV reveals no indication of physics beyond the standard model.Comment: 8 pages, 7 figures. Final version which appeared in Physical Review D Rapid Communication

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

Applications of electrified dust and dust devil electrodynamics to Martian atmospheric electricity

Atmospheric transport and suspension of dust frequently brings electrification, which may be substantial. Electric fields of 10 kVm-1 to 100 kVm-1 have been observed at the surface beneath suspended dust in the terrestrial atmosphere, and some electrification has been observed to persist in dust at levels to 5 km, as well as in volcanic plumes. The interaction between individual particles which causes the electrification is incompletely understood, and multiple processes are thought to be acting. A variation in particle charge with particle size, and the effect of gravitational separation explains to, some extent, the charge structures observed in terrestrial dust storms. More extensive flow-based modelling demonstrates that bulk electric fields in excess of 10 kV m-1 can be obtained rapidly (in less than 10 s) from rotating dust systems (dust devils) and that terrestrial breakdown fields can be obtained. Modelled profiles of electrical conductivity in the Martian atmosphere suggest the possibility of dust electrification, and dust devils have been suggested as a mechanism of charge separation able to maintain current flow between one region of the atmosphere and another, through a global circuit. Fundamental new understanding of Martian atmospheric electricity will result from the ExoMars mission, which carries the DREAMS (Dust characterization, Risk Assessment, and Environment Analyser on the Martian Surface)-MicroARES (Atmospheric Radiation and Electricity Sensor) instrumentation to Mars in 2016 for the first in situ measurements

Search for leptophobic Z ' bosons decaying into four-lepton final states in proton-proton collisions at root s=8 TeV

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Search for black holes and other new phenomena in high-multiplicity final states in proton-proton collisions at root s=13 TeV

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