415 research outputs found

    Weed management in organic echinacea (Echinacea purpurea) and lettuce (Lactuca sativa) production

    Get PDF
    Weed management is a major constraint in organic production. It can be expensive and time-consuming and severe crop yield losses may be incurred when weeds are not adequately controlled. Research on organic weed management (OWM) in herb and vegetable production is increasing internationally, although in Australia very little work has been done to assess current OWM knowledge among growers, and to test the efficacy and cost effectiveness of the weed management practices used by organic growers. The effect of hand weeding, tillage, hay mulch, pelletised paper mulch and an unweeded control treatment on weed growth, crop growth and cost effectiveness were evaluated in several field trials on the Northern Tablelands of New South Wales using lettuce (Lactuca sativa L.) and echinacea (Echinacea purpurea Moench. [L.]). Weed management in lettuce was cost-effectively achieved using cheaper weeding methods such as tillage. More expensive methods such as hand weeding and hay mulching controlled weeds well, but were less cost effective. For echinacea, cheaper in-crop weeding methods (e.g. tillage, unweeded control) had poor weed suppression and low crop yields, while the more expensive weeding methods, hand weeding and hay mulch, controlled weeds well and were cost effective. Paper mulch controlled weeds very well but, again, had lower yields and was therefore not cost effective. The results highlight several important advantages and disadvantages of currently used OWM methods in the field

    Charming penguins in B => K* pi, K (rho,omega,phi) decays

    Full text link
    We evaluate the decays B => K* pi, K (rho,omega,phi) adding the long distance charming penguin contributions to the short distance: Tree+Penguin amplitudes. We estimate the imaginary part of the charming penguin by an effective field theory inspired by the Heavy Quark Effective Theory and parameterize its real part. The final results for branching ratios depend on only two real parameters and show a significant role of the charming penguins. The overall agreement with the available experimental data is satisfactory.Comment: 13 pages, 1 figur

    Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV

    Get PDF
    Peer reviewe

    Measurement of the CP-Violating Asymmetry Amplitude sin2β\beta

    Get PDF
    We present results on time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 88 million Y(4S) --> B Bbar decays collected between 1999 and 2002 with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We study events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the other B meson is determined to be either a B0 or B0bar from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2beta, is derived from the decay-time distributions in such events. We measure sin2beta = 0.741 +/- 0.067 (stat) +/- 0.033 (syst) and |lambda| = 0.948 +/- 0.051 (stat) +/- 0.017 (syst). The magnitude of lambda is consistent with unity, in agreement with the Standard Model expectation of no direct CP violation in these modes

    Commercial Actors and the Governing of Education: the case of academy school sponsors in England.

    Get PDF
    grant number ESIO 1943X/1This article explores the ways in which commercial actors are operating in state education by focusing on the case study of England’s academies policy. First of all the discussion outlines the development of academies over time and the way in which the policy has provided opportunities for private actors to become involved in the state schooling system. The second part of the article focuses on empirical findings from interviews with academy sponsors as a way of understanding the nature of the role commercial actors play in academies. Commercial sponsor involvement in academies demonstrates a blurring of the boundaries between ‘public’ and ‘private’, and the article suggests that commercial actors need to be understood not merely as participants in this process, but as being active in the reconstruction of ‘public—private’ categories. Also, it is underlined that the commercial sponsors in this study cannot be disconnected from the locality in which they operate. In light of this, the article calls for greater attention to be devoted to understanding local assemblages of policy when attempting to explore the role played by commercial actors in the governance of education

    Measurement of the Branching Fractions for BωKB \to \omega K and BωπB \to \omega \pi

    Full text link
    We report improved measurements of branching fractions for charmless hadronic two-body {\it B} meson decays containing an ω\omega meson in the final state. The results are based on a data sample of 78 fb1^{-1} collected on the Υ(4S)\Upsilon(4S) resonance by the Belle detector. We measure the branching fractions B(B+ωK+)=(6.51.2+1.3±0.6)×106{\mathcal B}(B^+ \to \omega K^+) = (6.5^{+1.3}_{-1.2}\pm 0.6)\times 10^{-6} and B(B+ωπ+)=(5.71.3+1.4±0.6)×106.{\mathcal B}(B^+ \to \omega \pi^+) = (5.7^{+1.4}_{-1.3}\pm 0.6)\times 10^{-6}. We give 90% confidence upper limits for B(B0ωK0)<7.6×106{\mathcal B}(B^0 \to \omega K^0) < 7.6\times 10^{-6} and B(B0ωπ0)<1.9×106.{\mathcal B}(B^0 \to \omega \pi^0) < 1.9\times 10^{-6}. We also obtain the partial rate asymmetries ACP=0.060.18+0.21±0.01{\mathcal A}_{CP}=0.06^{+0.21}_{-0.18}\pm 0.01 for B±ωK±B^\pm \to \omega K^\pm and ACP=0.500.20+0.23±0.02{\mathcal A}_{CP}=0.50^{+0.23}_{-0.20}\pm 0.02 for B±ωπ±.B^\pm \to \omega \pi^\pm.Comment: 7 pages, 4 figures, tar.gz files submitted to PR

    EuFe2_2As2_2 under high pressure: an antiferromagnetic bulk superconductor

    Get PDF
    We report the ac magnetic susceptibility χac\chi_{ac} and resistivity ρ\rho measurements of EuFe2_2As2_2 under high pressure PP. By observing nearly 100% superconducting shielding and zero resistivity at PP = 28 kbar, we establish that PP-induced superconductivity occurs at TcT_c \sim~30 K in EuFe2_2As2_2. ρ\rho shows an anomalous nearly linear temperature dependence from room temperature down to TcT_c at the same PP. χac\chi_{ac} indicates that an antiferromagnetic order of Eu2+^{2+} moments with TNT_N \sim~20 K persists in the superconducting phase. The temperature dependence of the upper critical field is also determined.Comment: To appear in J. Phys. Soc. Jpn., Vol. 78 No.

    Measurements of the ϒ(1S), ϒ(2S), and ϒ(3S) differential cross sections in pp collisions at s=7TeV

    Get PDF
    Differential cross sections as a function of transverse momentum pTpT are presented for the production of ϒ(nS)ϒ(nS) (n = 1, 2, 3) states decaying into a pair of muons. Data corresponding to an integrated luminosity of 4.9View the MathML sourcefb−1 in pp collisions at View the MathML sources=7TeV were collected with the CMS detector at the LHC. The analysis selects events with dimuon rapidity |y|<1.2|y|<1.2 and dimuon transverse momentum in the range View the MathML source10<pT<100GeV. The measurements show a transition from an exponential to a power-law behavior at View the MathML sourcepT≈20GeV for the three ϒ states. Above that transition, the ϒ(3S)ϒ(3S) spectrum is significantly harder than that of the ϒ(1S)ϒ(1S). The ratios of the ϒ(3S)ϒ(3S) and ϒ(2S)ϒ(2S) differential cross sections to the ϒ(1S)ϒ(1S) cross section show a rise as pTpT increases at low pTpT, then become flatter at higher pTpT
    corecore