299 research outputs found

    Estudio de peso y rendimiento en canal de las razas Sanmartinera, CebĂș y sus cruces en los Llanos Orientales.

    Get PDF
    EvalĂșa el ganado Sanmartinero, CebĂș y sus cruces con Charolais, en ganancia de peso, producciĂłn de carne y rendimiento en canal. Se utilizaron 18 novillos divididos en 6 grupos de 3 animales cada uno, asĂ­: Sanmartinero (SM) y CebĂș (C) como razas puras, y Sm x C, C x Sm filial 2 (C x Sm F2), Sm x C F2 y Ch x C x Sm como cruces. Al destete los animales cruzados ganaron 160 gr mas por dĂ­a que los puros, en el postdestete los puros ganaron mas peso por dĂ­a que los cruzados. Los pesos promedios al finalizar la ceba en pasto braquiaria fueron: 436, 400, 483, 457, 431 y 468 kg y los pesos al presacrificio despuĂ©s de 24 horas de ayuno fueron: 399, 369, 448, 418, 395 y 429 kg para el Sm, C, Sm x C, C x Sm F2, Sm x C F2 y Ch x C x Sm, respectivamente. En el mismo orden de razas se obtuvieron los siguientes resultados: pesos promedios de las canales: 221, 216, 253, 243, 223 y 245 kg, rendimientos en canal: 55, 58, 56, 56, 56 y 57 por ciento, rendimientos en canal en base al peso vacĂ­o, sustrayendo el contenido intestinal: 61, 62, 60, 60, 62 y 62 por ciento. Se encontraron diferencias significativas para el peso de las canales entre puros y cruzados. El porcentaje promedio de la merma de los grupos postrefrigeraciĂłn en 24 horas a 6 grados centĂ­grados fue de 1.76 por ciento. En la evaluaciĂłn de expendio, se presentaron diferencias significativas para el peso de los cortes de primera, segunda y tercera entre los puros y cruzadosGanado de doble propĂłsito-Ganaderia doble proposit

    Antitumor activity of a small-molecule inhibitor of the histone kinase Haspin

    Get PDF
    The approval of histone deacetylase inhibitors for treatment of lymphoma subtypes has positioned histone modifications as potential targets for the development of new classes of anticancer drugs. Histones also undergo phosphorylation events, and Haspin is a protein kinase the only known target of which is phosphorylation of histone H3 at Thr3 residue (H3T3ph), which is necessary for mitosis progression. Mitotic kinases can be blocked by small drugs and several clinical trials are underway with these agents. As occurs with Aurora kinase inhibitors, Haspin might be an optimal candidate for the pharmacological development of these compounds. A high-throughput screening for Haspin inhibitors identified the CHR-6494 compound as being one promising such agent. We demonstrate that CHR-6494 reduces H3T3ph levels in a dose-dependent manner and causes a mitotic catastrophe characterized by metaphase misalignment, spindle abnormalities and centrosome amplification. From the cellular standpoint, the identified small-molecule Haspin inhibitor causes arrest in G2/M and subsequently apoptosis. Importantly, ex vivo assays also demonstrate its anti-angiogenetic features; in vivo, it shows antitumor potential in xenografted nude mice without any observed toxicity. Thus, CHR-6494 is a first-in-class Haspin inhibitor with a wide spectrum of anticancer effects that merits further preclinical research as a new member of the family of mitotic kinase inhibitors

    A study of CP violation in the decays B±→[K+K-π+π-]Dh± (h= K, π) and B±→[π+π-π+π-]Dh±

    Get PDF
    The first study of CP violation in the decay mode B±→[K+K-π+π-]Dh± , with h= K, π , is presented, exploiting a data sample of proton–proton collisions collected by the LHCb experiment that corresponds to an integrated luminosity of 9 \,fb - 1 . The analysis is performed in bins of phase space, which are optimised for sensitivity to local CP asymmetries. CP -violating observables that are sensitive to the angle Îł of the Unitarity Triangle are determined. The analysis requires external information on charm-decay parameters, which are currently taken from an amplitude analysis of LHCb data, but can be updated in the future when direct measurements become available. Measurements are also performed of phase-space integrated observables for B±→[K+K-π+π-]Dh± and B±→[π+π-π+π-]Dh± decays

    First observation and branching fraction measurement of the Λb0→Ds−p\Lambda_b^0\to D_s^- p decay

    Get PDF
    The first observation of the Λb0→Ds−p\Lambda_b^0\to D_s^- p decay is presented using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of s=13 TeV{\sqrt{s}=13 \,\textrm{TeV}}, corresponding to a total integrated luminosity of 6 fb−16\,\textrm{fb}^{-1}. Using the Λb0→Λc+π−\Lambda_b^0\to\Lambda_c^+\pi^- decay as the normalisation mode, the branching fraction of the Λb0→Ds−p\Lambda_b^0\to D_s^- p decay is measured to be B(Λb0→Ds−p)=(12.6±0.5±0.3±1.2)×10−6{\mathcal{B}(\Lambda_b^0\to D_s^- p)=(12.6 \pm 0.5 \pm 0.3 \pm 1.2 )\times 10^{-6}}, where the first uncertainty is statistical, the second systematic and the third due to uncertainties in the branching fractions of the Λb0→Λc+π−\Lambda_b^0\to\Lambda_c^+\pi^-, Ds−→K−K+π−D_s^- \to K^-K^+\pi^- and Λc+→pK−π+\Lambda_c^+\to p K^- \pi^+ decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-038.html (LHCb public pages

    Study of charmonium decays to KS0KπK^0_S K \pi in the B→(KS0Kπ)KB \to (K^0_S K \pi) K channels

    Get PDF
    A study of the B+→KS0K+K−π+B^+\to K^0_SK^+K^-\pi^+ and B+→KS0K+K+π−B^+\to K^0_SK^+K^+\pi^- decays is performed using proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV at the LHCb experiment. The KS0KπK^0_SK \pi invariant mass spectra from both decay modes reveal a rich content of charmonium resonances. New precise measurements of the ηc\eta_c and ηc(2S)\eta_c(2S) resonance parameters are performed and branching fraction measurements are obtained for B+B^+ decays to ηc\eta_c, J/ψJ/\psi, ηc(2S)\eta_c(2S) and χc1\chi_{c1} resonances. In particular, the first observation and branching fraction measurement of B+→χc0K0π+B^+ \to \chi_{c0} K^0 \pi^+ is reported as well as first measurements of the B+→K0K+K−π+B^+\to K^0K^+K^-\pi^+ and B+→K0K+K+π−B^+\to K^0K^+K^+\pi^- branching fractions. Dalitz plot analyses of ηc→KS0Kπ\eta_c \to K^0_SK\pi and ηc(2S)→KS0Kπ\eta_c(2S) \to K^0_SK\pi decays are performed. A new measurement of the amplitude and phase of the KπK \pi SS-wave as functions of the KπK \pi mass is performed, together with measurements of the K0∗(1430)K^*_0(1430), K0∗(1950)K^*_0(1950) and a0(1700)a_0(1700) parameters. Finally, the branching fractions of χc1\chi_{c1} decays to K∗K^* resonances are also measured.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-051.html (LHCb public pages

    First observation of a doubly charged tetraquark and its neutral partner

    Get PDF
    A combined amplitude analysis is performed for the decays B0→D‟0Ds+π−B^0 \rightarrow \overline{D}^0 D^+_s\pi^- and B+→D−Ds+π+B^+\rightarrow D^- D^+_s\pi^+, which are related by isospin symmetry. The analysis is based on data collected by the LHCb detector in proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV\,\rm{TeV}. The full data sample corresponds to an integrated luminosity of 9 fb−1\,\rm{fb^{-1}}. Two new resonant states with masses of 2.908±0.011±0.020 GeV2.908\pm0.011\pm0.020\,\rm{GeV} and widths of 0.136±0.023±0.011 GeV0.136\pm0.023\pm0.011\,\rm{GeV} are observed, which decay to Ds+π+D^+_s\pi^+ and Ds+π−D^+_s\pi^- respectively. The former state indicates the first observation of a doubly charged open-charm tetraquark state with minimal quark content [csˉudˉ][c\bar{s}u\bar{d}], and the latter state is a neutral tetraquark composed of [csˉuˉd][c\bar{s}\bar{u}d] quarks. Both states are found to have spin-parity 0+0^+, and their resonant parameters are consistent with each other, which suggests that they belong to an isospin triplet.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-026.html (LHCb public pages

    First observation of the B+→Ds+Ds−K+B^+ \rightarrow D_s^+ D_s^- K^+ decay

    Get PDF
    The B+→Ds+Ds−K+B^+ \rightarrow D_s^+ D_s^- K^+ decay is observed for the first time using proton-proton collision data collected by the LHCb detector at centre-of-mass energies of 77, 88 and 13 TeV13\, \text{TeV}, corresponding to an integrated luminosity of 9 fb−19\,\text{fb}^{-1}. Its branching fraction relative to that of the B+→D+D−K+B^{+} \rightarrow D^{+} D^{-} K^{+} decay is measured to be B(B+→Ds+Ds−K+)B(B+→D+D−K+)=0.525±0.033±0.027±0.034,\frac{B\left(B^{+} \rightarrow D_s^{+} D_s^{-} K^{+}\right)}{B\left(B^{+} \rightarrow D^{+} D^{-} K^{+}\right)}=0.525 \pm 0.033 \pm 0.027 \pm 0.034, where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the branching fractions of the Ds±→K∓K±π±D_s^{\pm} \rightarrow K^{\mp} K^{\pm} \pi^{\pm} and D±→K∓π±π±D^{\pm} \rightarrow K^{\mp} \pi^{\pm} \pi^{\pm} decays. This measurement fills an experimental gap in the knowledge of the family of Cabibbo−-favoured bˉ→cˉcsˉ\bar{b} \rightarrow \bar{c} c \bar{s} transitions and opens the path for unique studies of spectroscopy in future.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-019.html (LHCb public pages

    Observation of the Bs0 ⁣→D∗+D∗−B^0_s\!\to D^{*+}D^{*-} decay

    Get PDF
    The first observation of the Bs0 ⁣→D∗+D∗−B^0_s\!\to D^{*+}D^{*-} decay and the measurement of its branching ratio relative to the B0 ⁣→D∗+D∗−B^0\!\to D^{*+}D^{*-} decay are presented. The data sample used corresponds to an integrated luminosity of 9 fb−1\,\text{fb}^{-1} of proton-proton collisions recorded by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV\,\text{TeV} between 2011 and 2018. The decay is observed with a very high significance and the ratio of branching fractions is determined to be \begin{align*} \frac{\mathcal{B}(B^0_s\!\to D^{*+}D^{*-})}{\mathcal{B}(B^0\!\to D^{*+}D^{*-})} = 0.269 \pm 0.032 \pm 0.011 \pm 0.008\, , \end{align*} where the first uncertainty is statistical, the second systematic and the third due to the uncertainty of the fragmentation fraction ratio fs/fdf_s/f_d. The Bs0 ⁣→D∗+D∗−B^0_s\!\to D^{*+}D^{*-} branching fraction is calculated to be \begin{align*} \mathcal{B}(B^0_s\!\to D^{*+}D^{*-}) = (2.15 \pm 0.26 \pm 0.09 \pm 0.06 \pm 0.16)\times 10^{-4} \,, \end{align*} where the fourth uncertainty is due to the B0 ⁣→D∗+D∗−B^0\!\to D^{*+}D^{*-} branching fraction.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-023.html (LHCb public pages

    Amplitude analysis of B0→D‟0Ds+π−B^0 \rightarrow \overline{D}^0 D_s^+ \pi^- and B+→D−Ds+π+B^+ \rightarrow D^- D_s^+ \pi^+ decays

    Get PDF
    Resonant contributions in B0→D‟0Ds+π−B^0 \rightarrow \overline{D}^0 D^+_s\pi^- and B+→D−Ds+π+B^+\rightarrow D^- D^+_s\pi^+ decays are determined with an amplitude analysis, which is performed both separately and simultaneously, where in the latter case isospin symmetry between the decays is assumed. The analysis is based on data collected by the LHCb detector in proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV\rm{TeV}. The full data sample corresponds to an integrated luminosity of 9 fb−1\rm fb^{-1}. A doubly charged spin-0 open-charm tetraquark candidate together with a neutral partner, both with masses near 2.9 GeV2.9\,\rm{GeV}, are observed in the DsπD_s\pi decay channel.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-027.html (LHCb public pages

    Measurement of lepton universality parameters in B+→K+ℓ+ℓ−B^+\to K^+\ell^+\ell^- and B0→K∗0ℓ+ℓ−B^0\to K^{*0}\ell^+\ell^- decays

    Get PDF
    A simultaneous analysis of the B+→K+ℓ+ℓ−B^+\to K^+\ell^+\ell^- and B0→K∗0ℓ+ℓ−B^0\to K^{*0}\ell^+\ell^- decays is performed to test muon-electron universality in two ranges of the square of the dilepton invariant mass, q2q^2. The measurement uses a sample of beauty meson decays produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 99 fb−1\text{fb}^{-1}. A sequence of multivariate selections and strict particle identification requirements produce a higher signal purity and a better statistical sensitivity per unit luminosity than previous LHCb lepton universality tests using the same decay modes. Residual backgrounds due to misidentified hadronic decays are studied using data and included in the fit model. Each of the four lepton universality measurements reported is either the first in the given q2q^2 interval or supersedes previous LHCb measurements. The results are compatible with the predictions of the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-045.html (LHCb public pages
    • 

    corecore