An RFLP study of relationships between species, populations and resistance-breaking lines of tropical species of Meloidogyne

Afin d'établir l'identité de certaines espèces de #Meloidogyne, caractérisées par le phénotype estérasique pVI et pouvant se développer sur certains cultivars résistants, six de ces lignées sont comparées par RFLP à dix lignées de #M. incognita, sept de #M. arenaria, quatre de #M. javanica, une de #M. hapla et une de #M. mayaguensis. Deux groupes très homogènes sont identifiés : le premier comprend les lignées de #M. incognita, le deuxième les lignées pVI et la lignée de #M. mayaguensis; un troisième, plus variable, regroupe les lignées appartenant à #M. arenaria et à #M. javanica. Les lignées se développant sur cultivars résistants et dotées du phénotype pVI apparaissent comme une espèce distincte, #M. mayaguensis$, et non comme la conséquence de la sélection, par l'usage de cultivars résistants, de variants parmi les espèces tropicales. (Résumé d'auteur

Superluminal optical pulse propagation in nonlinear coherent media

The propagation of light-pulse with negative group-velocity in a nonlinear medium is studied theoretically. We show that the necessary conditions for these effects to be observable are realized in a three-level $\Lambda$-system interacting with a linearly polarized laser beam in the presence of a static magnetic field. In low power regime, when all other nonlinear processes are negligible, the light-induced Zeeman coherence cancels the resonant absorption of the medium almost completely, but preserves the dispersion anomalous and very high. As a result, a superluminal light pulse propagation can be observed in the sense that the peak of the transmitted pulse exits the medium before the peak of the incident pulse enters. There is no violation of causality and energy conservation. Moreover, the superluminal effects are prominently manifested in the reshaping of pulse, which is caused by the intensity-dependent pulse velocity. Unlike the shock wave formation in a nonlinear medium with normal dispersion, here, the self-steepening of the pulse trailing edge takes place due to the fact that the more intense parts of the pulse travel slower. The predicted effect can be easily observed in the well known schemes employed for studying of nonlinear magneto-optical rotation. The upper bound of sample length is found from the criterion that the pulse self-steepening and group-advance time are observable without pulse distortion caused by the group-velocity dispersion.Comment: 16 pages, 7 figure

The Carnegie Supernova Project. I. Third Photometry Data Release of Low-redshift Type Ia Supernovae and Other White Dwarf Explosions

We present final natural-system optical (ugriBV) and near-infrared (YJH) photometry of 134 supernovae (SNe) with probable white dwarf progenitors that were observed in 2004-2009 as part of the first stage of the Carnegie Supernova Project (CSP-I). The sample consists of 123 Type Ia SNe, 5 Type Iax SNe, 2 super-Chandrasekhar SN candidates, 2 Type Ia SNe interacting with circumstellar matter, and 2 SN 2006bt-like events. The redshifts of the objects range from to 0.0835; the median redshift is 0.0241. For 120 (90%) of these SNe, near-infrared photometry was obtained. Average optical extinction coefficients and color terms are derived and demonstrated to be stable during the five CSP-I observing campaigns. Measurements of the CSP-I near-infrared bandpasses are also described, and near-infrared color terms are estimated through synthetic photometry of stellar atmosphere models. Optical and near-infrared magnitudes of local sequences of tertiary standard stars for each supernova are given, and a new calibration of Y-band magnitudes of the Persson et al. standards in the CSP-I natural system is presented.Fil: Krisciunas, Kevin. Texas A&M University; Estados UnidosFil: Contreras, Carlos. University Aarhus; Dinamarca. Las Campanas Observatory; ChileFil: Burns, Christopher R.. Las Campanas Observatory; ChileFil: Phillips, M. M.. Las Campanas Observatory; ChileFil: Stritzinger, Maximilian D.. Las Campanas Observatory; Chile. University Aarhus; DinamarcaFil: Morrell, Nidia Irene. Las Campanas Observatory; ChileFil: Hamuy, Mario. Universidad de Chile; ChileFil: Anais, Jorge. Las Campanas Observatory; ChileFil: Boldt, Luis. Las Campanas Observatory; ChileFil: Busta, Luis. Las Campanas Observatory; ChileFil: Campillay, Abdo. Las Campanas Observatory; ChileFil: Castellón, Sergio. Las Campanas Observatory; ChileFil: Folatelli, Gaston. Las Campanas Observatory; Chile. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Freedman, Wendy L.. University of Chicago; Estados UnidosFil: González, Consuelo. Las Campanas Observatory; ChileFil: Hsiao, Eric Y.. Florida State University; Estados Unidos. University Aarhus; Dinamarca. Las Campanas Observatory; ChileFil: Krzeminski, Wojtek. Las Campanas Observatory; ChileFil: Persson, Sven Eric. Carnegie Observatories;Fil: Roth, Miguel. Gmto Corporation; Chile. Las Campanas Observatory; ChileFil: Salgado, Francisco. Leiden Observatory Research Institute; . Las Campanas Observatory; ChileFil: Serón, Jacqueline. Las Campanas Observatory; Chile. Cerro Tololo Inter American Observatory; ChileFil: Suntzeff, Nicholas B.. Texas A&M University; Estados UnidosFil: Torres, Simón. Soar Telescope; Chile. Las Campanas Observatory; ChileFil: Filippenko, Alexei V.. University of California at Berkeley; Estados UnidosFil: Li, Weidong. University of California at Berkeley; Estados UnidosFil: Madore, Barry F.. Jet Propulsion Laboratory, California Institute Of Technology; . Las Campanas Observatory; ChileFil: DePoy, D.L.. Texas A&M University; Estados UnidosFil: Marshall, Jennifer L.. Texas A&M University; Estados UnidosFil: Rheault, Jean Philippe. Texas A&M University; Estados UnidosFil: Villanueva, Steven. Texas A&M University; Estados Unidos. Ohio State University; Estados Unido

Gender moderates the relationship between empathy and aggressiveness in sport: The mediating role of anger

This research investigated whether gender moderates, and anger mediates, the relationship between empathy (i.e., perspective taking and empathic concern) and aggressiveness in sport. In Study 1, perspective taking and empathic concern were negatively associated with aggressiveness, and this effect was stronger in women compared to men. In Study 2, perspective taking was a negative predictor of aggressiveness and antisocial behavior in sport, and anger mediated these relationships in women, but not in men. Our findings suggest that empathy and emotion-based strategies targeted at reducing aggressiveness in sport need to be tailored for males and females

Endangered sawfishes and river sharks in Western Australia

The coastal waters of the northern Pilbara and the western Kimberley are a global hotspot for sawfish (Pristidae) diversity, with four of the world’s seven1 species found there; these four species comprise all of the known Australian species. This unique group of rays is readily identified by the presence of a blade like snout possessing enlarged tooth like denticles known as rostral teeth (Last and Stevens 2009). Globally, almost all sawfishes have undergone major declines in both range and abundance, largely as a result of their vulnerability to entanglement in fishing nets, but also through loss of habitat. It is only recently that information on the distribution, ecology, biology, population demographics and genetics and habitat utilization of the Australian sawfish fauna has started to become available, with much of this information restricted to grey literature or as unpublished work in progress. There is limited (or no) information on the size of the remaining populations, but many of the world’s sawfish populations are thought to survive in small fragmented areas (e.g. Simpfendorfer 2000). The four Australian species are from two genera, and are typically found throughout northern Australia, but accurate distributional descriptions are hindered by a lack of targeted surveying and are based on: limited surveys, from anecdotal reports or from collections of dried rostra. However, the Pilbara coast and west Kimberley are known to represent an important area for the four species, namely Freshwater Sawfish (Pristis microdon), Dwarf Sawfish (Pristis clavata), Green Sawfish (Pristis zijsron) and the Narrow Sawfish (Anoxypristis cuspidata).The first three of these species are listed as vulnerable under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and these form the basis of this review; although all are protected species within Western Australia under the Fish Resource Management Act 1994 (FRMA Act). Pristis zijsron was also listed under Schedule 1 of the Wildlife Conservation Act 1950 in Western Australia in 2006.Woodside Energy Ltd contracted the Centre for Fish & Fisheries Research (Murdoch University) to provide an overview of the current knowledge of the three EPBC Act listed pristids (P. microdon, P. clavata and P. zijsron) and also the Endangered (EPBC Act) Northern River Shark (Glyphis garricki) in Western Australian waters.Glyphis garricki was discovered in Western Australia in 2002 (Thorburn and Morgan 2004) and its formal description is recent (Compagno et al. 2008).Collectively, these species represent 50% of Australia’s elasmobranchs that are listed as Vulnerable or higher under the EPBC Act This report presents all known information with regard to their distribution in Western Australia, morphological characteristics, habitat utilization and population structure and genetic diversity in relation to northern Australia populations. The relevance of these data are then discussed in relation to the James Price Point development

Nucleon Polarizabilities from Deuteron Compton Scattering within a Green's-Function Hybrid Approach

We examine elastic Compton scattering from the deuteron for photon energies ranging from zero to 100 MeV, using state-of-the-art deuteron wave functions and NN-potentials. Nucleon-nucleon rescattering between emission and absorption of the two photons is treated by Green's functions in order to ensure gauge invariance and the correct Thomson limit. With this Green's-function hybrid approach, we fulfill the low-energy theorem of deuteron Compton scattering and there is no significant dependence on the deuteron wave function used. Concerning the nucleon structure, we use Chiral Effective Field Theory with explicit \Delta(1232) degrees of freedom within the Small Scale Expansion up to leading-one-loop order. Agreement with available data is good at all energies. Our 2-parameter fit to all elastic $\gamma d$ data leads to values for the static isoscalar dipole polarizabilities which are in excellent agreement with the isoscalar Baldin sum rule. Taking this value as additional input, we find \alpha_E^s= (11.3+-0.7(stat)+-0.6(Baldin)) x 10^{-4} fm^3 and \beta_M^s = (3.2-+0.7(stat)+-0.6(Baldin)) x 10^{-4} fm^3 and conclude by comparison to the proton numbers that neutron and proton polarizabilities are essentially the same.Comment: 47 pages LaTeX2e with 20 figures in 59 .eps files, using graphicx. Minor modifications; extended discussion of theoretical uncertainties of polarisabilities extraction. Version accepted for publication in EPJ

Gravitational Lensing at Millimeter Wavelengths

With today's millimeter and submillimeter instruments observers use gravitational lensing mostly as a tool to boost the sensitivity when observing distant objects. This is evident through the dominance of gravitationally lensed objects among those detected in CO rotational lines at z>1. It is also evident in the use of lensing magnification by galaxy clusters in order to reach faint submm/mm continuum sources. There are, however, a few cases where millimeter lines have been directly involved in understanding lensing configurations. Future mm/submm instruments, such as the ALMA interferometer, will have both the sensitivity and the angular resolution to allow detailed observations of gravitational lenses. The almost constant sensitivity to dust emission over the redshift range z=1-10 means that the likelihood for strong lensing of dust continuum sources is much higher than for optically selected sources. A large number of new strong lenses are therefore likely to be discovered with ALMA, allowing a direct assessment of cosmological parameters through lens statistics. Combined with an angular resolution <0.1", ALMA will also be efficient for probing the gravitational potential of galaxy clusters, where we will be able to study both the sources and the lenses themselves, free of obscuration and extinction corrections, derive rotation curves for the lenses, their orientation and, thus, greatly constrain lens models.Comment: 69 pages, Review on quasar lensing. Part of a LNP Topical Volume on "Dark matter and gravitational lensing", eds. F. Courbin, D. Minniti. To be published by Springer-Verlag 2002. Paper with full resolution figures can be found at ftp://oden.oso.chalmers.se/pub/tommy/mmviews.ps.g

Effective theory of the Delta(1232) in Compton scattering off the nucleon

We formulate a new power-counting scheme for a chiral effective field theory of nucleons, pions, and Deltas. This extends chiral perturbation theory into the Delta-resonance region. We calculate nucleon Compton scattering up to next-to-leading order in this theory. The resultant description of existing $\gamma$p cross section data is very good for photon energies up to about 300 MeV. We also find reasonable numbers for the spin-independent polarizabilities $\alpha_p$ and $\beta_p$.Comment: 29 pp, 9 figs. Minor revisions. To be published in PR

Setdb1-mediated H3K9 methylation is enriched on the inactive X and plays a role in its epigenetic silencing

Background: The presence of histone 3 lysine 9 (H3K9) methylation on the mouse inactive X chromosome has been controversial over the last 15 years, and the functional role of H3K9 methylation in X chromosome inactivation in any species has remained largely unexplored. Results: Here we report the first genomic analysis of H3K9 di- and tri-methylation on the inactive X: we find they are enriched at the intergenic, gene poor regions of the inactive X, interspersed between H3K27 tri-methylation domains found in the gene dense regions. Although H3K9 methylation is predominantly non-genic, we find that depletion of H3K9 methylation via depletion of H3K9 methyltransferase Set domain bifurcated 1 (Setdb1) during the establishment of X inactivation, results in failure of silencing for around 150 genes on the inactive X. By contrast, we find a very minor role for Setdb1-mediated H3K9 methylation once X inactivation is fully established. In addition to failed gene silencing, we observed a specific failure to silence X-linked long-terminal repeat class repetitive elements. Conclusions: Here we have shown that H3K9 methylation clearly marks the murine inactive X chromosome. The role of this mark is most apparent during the establishment phase of gene silencing, with a more muted effect on maintenance of the silent state. Based on our data, we hypothesise that Setdb1-mediated H3K9 methylation plays a role in epigenetic silencing of the inactive X via silencing of the repeats, which itself facilitates gene silencing through alterations to the conformation of the whole inactive X chromosome.Andrew Keniry, Linden J. Gearing, Natasha Jansz, Joy Liu, Aliaksei Z. Holik, Peter F. Hickey, Sarah A. Kinkel, Darcy L. Moore, Kelsey Breslin, Kelan Chen, Ruijie Liu, Catherine Phillips, Miha Pakusch, Christine Biben, Julie M. Sheridan, Benjamin T. Kile, Catherine Carmichael, Matthew E. Ritchie, Douglas J. Hilton and Marnie E. Blewit