Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at sqrt[s]=510 GeV in p[over →]+p[over →] Collisions.

We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over →]+p[over →] collisions at sqrt[s]=510 GeV. The measurements have been performed at midrapidity (|η|<0.25) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at sqrt[s]=510 GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range 0.02

Probing Gluon Spin-Momentum Correlations in Transversely Polarized Protons through Midrapidity Isolated Direct Photons in p

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200 GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

Lytic enzyme-assisted germination of Bacillus anthracis and Bacillus subtilis spores.

AIMS: The goal of this work was to determine conditions under which external application of a spore germination-specific lytic enzyme (GSLE) can increase the germination efficiency of spore populations. METHODS AND RESULTS: The Bacillus anthracis GSLE SleB was applied to native and coat-disrupted B. anthracis and Bacillus subtilis spores. SleB was inactive on native spores but was able to trigger rapid germination of coat-disrupted spores. Using spores lacking their GSLEs or their germinant receptors to model poorly germinating spores, SleB application was able to increase colony-forming efficiency 100-fold for native spores and >1000-fold for coat-disrupted spores. SleB effects on GSLE-deficient spores were greater than on germinant receptor-deficient spores. CONCLUSIONS: SleB treatment can increase spore germination efficiency. The greater effect of SleB on coat-disrupted spores is presumably due to the greater access afforded to the cortex. However, SleB apparently gained access to the cortex of native spores after they responded to nutrients and completed stage I of germination, which may result in the disruption of coat structure. SIGNIFICANCE AND IMPACT OF THE STUDY: Treatment of spore populations with a GSLE can increase germination efficiency. Such a treatment might be utilized to increase the rapid activation of industrial spore-based products.

Neuronal migration defect: a case of subcortical heterotopia in a California sea lion.

A 2 and a half-year-old male California sea lion (Zalophus californianus) presented with a history of intermittent generalized seizures. Magnetic resonance imaging revealed a large focal mass occupying the right cerebral hemisphere with moderate dilatation of the contralateral lateral ventricle. At necropsy, the right cerebral hemispheric white matter was expanded by numerous irregularly shaped, pale pink nodules up to 10 mm in diameter. The overlying cortex was characterized by increased numbers of small, poorly developed gyri with shallow, often indistinct, sulci (polymicrogyria). Microscopically, nodules were composed of neurons, oligodendroglia, microglia, and supporting neuropil and were well delineated from the surrounding white matter. The gross, histological, and immunohistochemical features of this lesion are consistent with a neuronal migration defect resulting in unilateral subcortical heterotopia.

A comparative study of adolescents' perceptions of normal-speaking and dysarthric children.

The purpose of this investigation was to compare adolescents' perceptions of the nonspeech characteristics of dysarthric and normal speakers. Recordings of six three-word phrases produced by 16 speakers, eight cerebral palsied and eight normal-speaking children, were presented to 19 students for judgments of nonspeech characteristics on a semantic differential scale containing 22 bipolar adjective pairs. Results of their ratings indicated that for all 22 adjective pairs the normal speakers were judged more positively than the dysarthric speakers. Moreover, the differences in listeners' ratings between the two speaker groups were statistically significant for all adjective pairs. Implications of these findings and their comparison to the judgments of peer and adult listeners are discussed.

Adolescents' perceptions of normal and voice-disordered children.

The purpose of this investigation was to compare adolescents' perceptions of the nonspeech characteristics of voice-disordered and normal speakers. Recordings of six three-word phrases produced by 16 speakers, eight voice-disordered and eight normal-speaking children, were presented to 19 adolescent students for judgments of nonspeech characteristics on a semantic differential scale containing 22 bipolar adjective pairs. Results of their ratings indicated that for 15 of the 22 pairs (68.2%) the normal speakers were judged more positively than the voice-disordered speakers. Moreover, for 9 of the 22 pairs (40.9%) the differences in listeners' ratings between the two speaker groups were statistically significant. Implications of these findings concerning developmental trends in the perception of voice disorders and their potential impact on mainstreaming in schools are discussed.

Tremorgenic toxin from Penicillium veruculosum.

A new mycotoxin that produces severe tremors and acute toxicity when administered orally or intraperitoneally (ip) to mice and 1-day-old cockerels was obtained from a strain of Penicillium verruculosum Peyronel isolated from peanuts. The ip 50% lethal dose (LD(50)) of this tremorgen was 2.4 mg/kg in mice and 15.2 mg/kg in chickens. Orally administered LD(50) values for the toxin were 126.7 mg/kg in mice and 365.5 mg/kg in chickens. The trivial name "verruculogen" is proposed for this tremorgenic mycotoxin. Physical and chemical characteristics of the mycotoxin are described.