Hexamermis macrostoma n. sp. (Nemata : Mermithidae) parasitizing the cricket Gryllodes laplatae (Orthoptera : Gryllidae) in Argentina

Dans cet article est décrite et illustrée la nouvelle espèce #Hexamermis macrostoma n. sp. Une clé d'identification des espèces argentines du genre #Hexamermis est proposée. (Résumé d'auteur

Identification of Heterorhabditis (Nematoda : Heterorhabditidae) from California with a new species isolated from the larvae of the ghost moth Hepialis californicus (Lepidoptera : Hepialidae) from the Bodega Bay Natural Reserve

Les méthodes de taxonomie classique de même que des essais de croisement et l'amplification au hasard de l'ADN polymorphique (RAPD) ont été utilisés pour détecter les différences morphologiques et génétiques entre populations d'#Heterorhabditis Pointar, 1975 provenant de Californie. Une nouvelle espèce, #Heterorhabditis hepialius sp. n., présente dans des chenilles d'#Hepialis californicus provenant de la baie de Bodega (Californie, Etats-Unis d'Amérique) est décrite et illustrée. Représentant la huitième espèce du genre, #H. hepialius sp. n. est caractérisé par la morphologie des spicules, du gubernaculum, et de la queue de la femelle ainsi que les rapports E et F chez les juvéniles infestants. Des données sur sa biologie sont également fournies. (Résumé d'auteur

Post-emergence application of liquid swine manure in east central Saskatchewan

Non-Peer ReviewedIn early 1997, the Prairie Protein Action Committee was established and one of its objectives was to identify ways to meet the increasing demand for wheat with specific protein quality and quantity (Fowler et al. 1998). The main areas of concern were low protein levels in western Canadian wheat and increased competition on the world market for high protein wheat. To address these concerns, one of the objectives was to identify research needs relating to the production and management of wheat protein. Protein quality can be enhanced by genetic improvement or by N fertility management. Among the main objectives in plant breeding programs are the need to increase yield and protein. However, the two traits have generally been found to be negatively related. This negative relationship may be as a result of dilution of the protein concentration as carbohydrates in the endosperm increase with yield. Thus, genetic improvement may have a small contribution toward enhancement of protein content in wheat. Hucl et al. (1998) found that less than 3% of variations in protein concentration in spring wheat was due to genetic variation, whereas over 80% of the variation was due to environmental effects, which include N fertility. Campbell et al. (1997) noted that in the Brown soil zone of Saskatchewan, 18% of the protein variation was due to N fertility. Within a cultivar, up to 99% of the variability in grain protein could be due to soil N variability (Fowler 1986). Hence, N fertility management is key to improving protein quality in wheat. Livestock manure application as a N source to boost yield and protein of wheat offers an alternative to chemical N fertilizers. There is opportunity to enhance protein levels in cereals and achieve protein premiums by delaying manure application and applying it post-emergent to cereals. Delayed manure application also helps widen the window of application and reduce manure application costs. Hence, the objective of this study was to determine the effects of low disturbance, post-emergent liquid swine manure injection on wheat protein and yield in east central Saskatchewan. This paper presents the results of the first two years of this three year study

Motion of rotatory molecular motor and chemical reaction rate

We examine the dependence of the physical quantities of the rotatory molecular motor, such as the rotation velocity and the proton translocation rate, on the chemical reaction rate using the model based only on diffusion process. A peculiar behavior of proton translocation is found and the energy transduction efficiency of the motor protein is enhanced by this behavior. We give a natural explanation that this behavior is universal when certain inequalities between chemical reaction rates hold. That may give a clue to examine whether the motion of the molecular motor is dominated by diffusion process or not.Comment: 12 pages, 8 figure

Demonstration of the temporal matter-wave Talbot effect for trapped matter waves

We demonstrate the temporal Talbot effect for trapped matter waves using ultracold atoms in an optical lattice. We investigate the phase evolution of an array of essentially non-interacting matter waves and observe matter-wave collapse and revival in the form of a Talbot interference pattern. By using long expansion times, we image momentum space with sub-recoil resolution, allowing us to observe fractional Talbot fringes up to 10th order.Comment: 17 pages, 7 figure

Kaon Production and Kaon to Pion Ratio in Au+Au Collisions at \snn=130 GeV

Mid-rapidity transverse mass spectra and multiplicity densities of charged and neutral kaons are reported for Au+Au collisions at \snn=130 GeV at RHIC. The spectra are exponential in transverse mass, with an inverse slope of about 280 MeV in central collisions. The multiplicity densities for these particles scale with the negative hadron pseudo-rapidity density. The charged kaon to pion ratios are $K^+/\pi^- = 0.161 \pm 0.002 {\rm (stat)} \pm 0.024 {\rm (syst)}$ and $K^-/\pi^- = 0.146 \pm 0.002 {\rm (stat)} \pm 0.022 {\rm (syst)}$ for the most central collisions. The $K^+/\pi^-$ ratio is lower than the same ratio observed at the SPS while the $K^-/\pi^-$ is higher than the SPS result. Both ratios are enhanced by about 50% relative to p+p and $\bar{\rm p}$+p collision data at similar energies.Comment: 6 pages, 3 figures, 1 tabl

Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV

We report the STAR measurement of Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV. Using the event mixing technique, the Phi spectra and yields are obtained at mid-rapidity for five centrality bins in Au+Au collisions and for non-singly-diffractive p+p collisions. It is found that the Phi transverse momentum distributions from Au+Au collisions are better fitted with a single-exponential while the p+p spectrum is better described by a double-exponential distribution. The measured nuclear modification factors indicate that Phi production in central Au+Au collisions is suppressed relative to peripheral collisions when scaled by the number of binary collisions. The systematics of versus centrality and the constant Phi/K- ratio versus beam species, centrality, and collision energy rule out kaon coalescence as the dominant mechanism for Phi production.Comment: 6 pages, 3 figures, submitted to Phys. Rev. Let

Azimuthal anisotropy at RHIC: the first and fourth harmonics

We report the first observations of the first harmonic (directed flow, v_1), and the fourth harmonic (v_4), in the azimuthal distribution of particles with respect to the reaction plane in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). Both measurements were done taking advantage of the large elliptic flow (v_2) generated at RHIC. From the correlation of v_2 with v_1 it is determined that v_2 is positive, or {\it in-plane}. The integrated v_4 is about a factor of 10 smaller than v_2. For the sixth (v_6) and eighth (v_8) harmonics upper limits on the magnitudes are reported.Comment: 6 pages with 3 figures, as accepted for Phys. Rev. Letters The data tables are at http://www.star.bnl.gov/central/publications/pubDetail.php?id=3