Rank-one flavor violation and B-meson anomalies

We assume that the quark-flavor coefficients matrix of the semileptonic operators addressing the neutral-current B-meson anomalies has rank-one, i.e. it can be described by a single vector in quark-flavor space. By correlating the observed anomalies to other flavor and high-pT observables, we constrain its possible directions and we show that a large region of the parameter space of this framework will be explored by flavor data from the NA62, KOTO, LHCb and Belle II experiments

Somatostatin subtype-2 receptor-targeted metal-based anticancer complexes

Conjugates of a dicarba analogue of octreotide, a potent somatostatin agonist whose receptors are overexpressed on tumor cells, with [PtCl 2(dap)] (dap = 1-(carboxylic acid)-1,2-diaminoethane) (3), [(η 6-bip)Os(4-CO 2-pico)Cl] (bip = biphenyl, pico = picolinate) (4), [(η 6-p-cym)RuCl(dap)] + (p-cym = p-cymene) (5), and [(η 6-p-cym)RuCl(imidazole-CO 2H)(PPh 3)] + (6), were synthesized by using a solid-phase approach. Conjugates 3-5 readily underwent hydrolysis and DNA binding, whereas conjugate 6 was inert to ligand substitution. NMR spectroscopy and molecular dynamics calculations showed that conjugate formation does not perturb the overall peptide structure. Only 6 exhibited antiproliferative activity in human tumor cells (IC 50 = 63 ± 2 μ in MCF-7 cells and IC 50 = 26 ± 3 μ in DU-145 cells) with active participation of somatostatin receptors in cellular uptake. Similar cytotoxic activity was found in a normal cell line (IC 50 = 45 ± 2.6 μ in CHO cells), which can be attributed to a similar level of expression of somatostatin subtype-2 receptor. These studies provide new insights into the effect of receptor-binding peptide conjugation on the activity of metal-based anticancer drugs, and demonstrate the potential of such hybrid compounds to target tumor cells specifically. © 2012 American Chemical Society

Rayleigh type behavior of the Young's modulus of unpoled ferroelectric ceramics and its dependence on temperature

3 pages, 4 figures.The dependence on stress of the low frequency Young's modulus and mechanical losses of unpoled ferroelectric ceramics has been studied as a function of temperature. The Young's modulus of unpoled Pb(Zr,Ti)O3 (PZT) showed a Rayleigh type dependence, analogous to the one already described for the longitudinal piezoelectric coefficient. This has been associated to ferroelectric/ferroelastic domain wall movements across, and their pinning/depinning on, randomly distributed defects. The Rayleigh coefficient was found to increase with temperature. The activation energy of the Rayleigh process was obtained, which must be related to the pinning energy. The Young's modulus of Mn doped 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 showed no stress dependence.This work has been funded by the European Commision (PIRAMID Growth Project No. G5RD-CT-2001-00456) and the Spanish McyT (Acción Especial MAT2001-4819-E and Project No. MAT2002-00463).Peer reviewe

To (b)e or not to (b)e: no electrons at LHCb

Acknowledgements: This project has received support from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 860881-HIDDeN [S.D.G.]. This study has been carried out within the INFN project (Iniziativa Specifica) QFT-HEP [M.N.B.]. J.M. gratefully acknowledges the financial support from ICREA under the ICREA Academia programme and from the Pauli Center (Zurich) and the Physics Department of University of Zurich. J.M. and A.B. also received financial support from Spanish Ministry of Science, Innovation and Universities (project PID2020-112965GB-I00) and from the Research Grant Agency of the Government of Catalonia (project SGR 1069). The work of B.C. is supported by the Margarita Salas postdoctoral program funded by the European Union-NextGenerationEU. B.C. also thanks the CERN Theory Division, where part of this work was done, for hospitality and the Cambridge Pheno Working Group for helpful discussions.AbstractWe discuss the impact of the recent LHCb update on the two lepton-flavour universality ratios $$R_K$$ R K and $$R_{K^*}$$ R K ∗ , and the CMS update of $$B({B_s \rightarrow \mu ^+\mu ^-})$$ B ( B s → μ + μ - ) regarding the possibility of New Physics in $$b\rightarrow s\ell ^+\ell ^-$$ b → s ℓ + ℓ - decays. We perform global fits of the New Physics Wilson coefficients defined in the model-independent approach of the Weak Effective Theory at the b-quark mass. We discuss three different frameworks for this analysis: (i) an update limited to the experimental data but using the same theoretical framework as in earlier works, (ii) a full update concerning both the experimental inputs and the theoretical framework, (iii) an analysis without the LHCb results on electron modes. The comparison between these various sets of results allows us to identify the differences stemming from the various components of the analysis: new experimental results, new inputs for the hadronic form factors, the role played by LHCb data on electron modes. As expected, the significance of all New Physics hypotheses gets reduced after the LHCb announcements on $$R_{K^{(*)}}$$ R K ( ∗ ) while the hypothesis of a lepton-flavour-universal contribution to the Wilson coefficient of the semileptonic $$O_{9\ell }$$ O 9 ℓ operators (possibly with a very small lepton-flavour-universality violating component) is clearly reinforced. We also discuss the possibility of a long-distance charm-loop contribution through a mode-by-mode analysis and we find that the preferred values for the $${\mathcal C}_{9\mu }$$ C 9 μ Wilson coefficient are consistent throughout the different $$b\rightarrow s\mu ^+\mu ^-$$ b → s μ + μ - modes and that there is no significant evidence of non-constant $$q^2$$ q 2 dependencies, which would indicate the presence of a long-distance charm-loop contribution beyond those already included.</jats:p

To (b)e or not to (b)e: no electrons at LHCb

Acknowledgements: This project has received support from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 860881-HIDDeN [S.D.G.]. This study has been carried out within the INFN project (Iniziativa Specifica) QFT-HEP [M.N.B.]. J.M. gratefully acknowledges the financial support from ICREA under the ICREA Academia programme and from the Pauli Center (Zurich) and the Physics Department of University of Zurich. J.M. and A.B. also received financial support from Spanish Ministry of Science, Innovation and Universities (project PID2020-112965GB-I00) and from the Research Grant Agency of the Government of Catalonia (project SGR 1069). The work of B.C. is supported by the Margarita Salas postdoctoral program funded by the European Union-NextGenerationEU. B.C. also thanks the CERN Theory Division, where part of this work was done, for hospitality and the Cambridge Pheno Working Group for helpful discussions.AbstractWe discuss the impact of the recent LHCb update on the two lepton-flavour universality ratios $$R_K$$ R K and $$R_{K^*}$$ R K ∗ , and the CMS update of $$B({B_s \rightarrow \mu ^+\mu ^-})$$ B ( B s → μ + μ - ) regarding the possibility of New Physics in $$b\rightarrow s\ell ^+\ell ^-$$ b → s ℓ + ℓ - decays. We perform global fits of the New Physics Wilson coefficients defined in the model-independent approach of the Weak Effective Theory at the b-quark mass. We discuss three different frameworks for this analysis: (i) an update limited to the experimental data but using the same theoretical framework as in earlier works, (ii) a full update concerning both the experimental inputs and the theoretical framework, (iii) an analysis without the LHCb results on electron modes. The comparison between these various sets of results allows us to identify the differences stemming from the various components of the analysis: new experimental results, new inputs for the hadronic form factors, the role played by LHCb data on electron modes. As expected, the significance of all New Physics hypotheses gets reduced after the LHCb announcements on $$R_{K^{(*)}}$$ R K ( ∗ ) while the hypothesis of a lepton-flavour-universal contribution to the Wilson coefficient of the semileptonic $$O_{9\ell }$$ O 9 ℓ operators (possibly with a very small lepton-flavour-universality violating component) is clearly reinforced. We also discuss the possibility of a long-distance charm-loop contribution through a mode-by-mode analysis and we find that the preferred values for the $${\mathcal C}_{9\mu }$$ C 9 μ Wilson coefficient are consistent throughout the different $$b\rightarrow s\mu ^+\mu ^-$$ b → s μ + μ - modes and that there is no significant evidence of non-constant $$q^2$$ q 2 dependencies, which would indicate the presence of a long-distance charm-loop contribution beyond those already included.</jats:p

Size effects on the macroscopic properties of the relaxor ferroelectric Pb(Mg1/3Nb2/3)O3-PbTiO3 solid solution

International audience[No abstract available