We present an analysis of the existing data on charmonium hadro-production based on non-relativistic QCD (NRQCD) calculations at the next-to-leading order (NLO). All the data on J/psi and psi' ...production in fixed-target experiments and on pp collisions at low energy are included. We find that the amount of color octet contribution needed to describe the data is about 1/10 of that found at the Tevatron.
The HERA-B collaboration has studied the production of charmonium and open charm states in collisions of 920 GeV protons with wire targets of different materials. The acceptance of the HERA-B ...spectrometer covers negative values of
x
F
up to
x
F
=
−
0.3
and a broad range in transverse momentum from 0.0 to 4.8GeV/
c. The studies presented in this paper include
J
/
ψ
differential distributions and the suppression of
J
/
ψ
production in nuclear media. Furthermore, production cross sections and cross section ratios for open charm mesons are discussed.
Eur.Phys.J.C24:361-371,2002 The relation between the branching ratios and direct CP asymmetries of B -->
K pi decays and the angle gamma of the CKM unitarity triangle is studied
numerically in the ...general framework of the SU(3) approach, with minimal
assumptions about the parameters not fixed by flavour-symmetry arguments.
Experimental and theoretical uncertainties are subjected to a statistical
treatment according to the Bayesian method. In this context, the experimental
limits recently obtained by CLEO, BaBar and Belle for the direct CP asymmetries
are translated into the bound |gamma - 90 deg| > 21 deg at the 95% C.L.. A
detailed analysis is carried out to evaluate the conditions under which
measurements of the CP averaged branching ratios may place a significant
constraint on gamma. Predictions for the ratios of charged (R_c) and neutral
(R_n) B --> K pi decays are also presented.
Riv.Nuovo Cim.23N3:1,2000 A complete review of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements and
of the experimental methods for their determination is presented. A critical
analysis of the ...relevant experimental results, and in particular of the most
recent ones, allows to improve the accuracies of all the matrix elements. A
chi-square minimization with the three-family unitarity constraint on the CKM
matrix is performed to test the current interpretation of the CP violating
phenomena inside the Standard Model. A complete and unambiguous solution
satisfying all the imposed constraints is found. As a by-product of the fit,
the precision on the values of the matrix elements is further increased and it
is possible to obtain estimates for the important CP violation observables $sin
2\beta$, $sin 2\alpha$ and $\gamma$. Finally, an independent estimation of the
CKM elements based on a Bayesian approach is performed. This complementary
method constitutes a check of the results obtained, providing also the
probability functions of the CKM elements and of the related quantities.
The relation between the branching ratios and direct CP asymmetries of B --> K pi decays and the angle gamma of the CKM unitarity triangle is studied numerically in the general framework of the SU(3) ...approach, with minimal assumptions about the parameters not fixed by flavour-symmetry arguments. Experimental and theoretical uncertainties are subjected to a statistical treatment according to the Bayesian method. In this context, the experimental limits recently obtained by CLEO, BaBar and Belle for the direct CP asymmetries are translated into the bound |gamma - 90 deg| > 21 deg at the 95% C.L.. A detailed analysis is carried out to evaluate the conditions under which measurements of the CP averaged branching ratios may place a significant constraint on gamma. Predictions for the ratios of charged (R_c) and neutral (R_n) B --> K pi decays are also presented.
A complete review of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements and of the experimental methods for their determination is presented. A critical analysis of the relevant experimental ...results, and in particular of the most recent ones, allows to improve the accuracies of all the matrix elements. A chi-square minimization with the three-family unitarity constraint on the CKM matrix is performed to test the current interpretation of the CP violating phenomena inside the Standard Model. A complete and unambiguous solution satisfying all the imposed constraints is found. As a by-product of the fit, the precision on the values of the matrix elements is further increased and it is possible to obtain estimates for the important CP violation observables \(sin 2\beta\), \(sin 2\alpha\) and \(\gamma\). Finally, an independent estimation of the CKM elements based on a Bayesian approach is performed. This complementary method constitutes a check of the results obtained, providing also the probability functions of the CKM elements and of the related quantities.
We have searched for Theta^+(1540) and Xi^{--}(1862) pentaquark candidates in proton-induced reactions on C, Ti and W targets at mid-rapidity and \sqrt{s} = 41.6 GeV. In 2x10^8 inelastic events we ...find no evidence for narrow (sigma~5 MeV) signals in the Theta^+ -> pK_s and Xi^{--} -> Xi^-pi^- channels: our 95% CL upper limits (UL) for the inclusive production cross section times branching fraction Bx(dsigma/dy)|_{y~0} are 3.7 and 2.5 microb/N. The UL of the yield ratio of Theta^+ / Lambda(1520) < 2.7% is significantly lower than model predictions. Our UL of BxXi^{--} / Xi(1530)^0 < 4% is at variance with the results that have provided first evidence for the Xi^{--} signal.
In recent years telomerase has been identified as a new promising target in oncology and consequently new telomerase inhibitors have been intensely explored as anticancer agents. Focused screening of ...several polyhydroxylated flavonoids has allowed us to identify 7,8,3‘,4‘-tetrahydroxyflavone 1 as a new telomerase inhibitor with an interesting in vitro activity in a Flash-Plate assay (IC50 = 0.2 μM) that has been confirmed in the classical TRAP assay. Starting from this compound, we developed a medicinal chemistry program to optimize our lead, and in particular to replace one of the two catechols with potential bioisosteres. From this study, new structural analogues characterized by submicromolar potencies have been obtained. Their synthesis and biological activity are described.
Prodigiosins (Ps) represent a family of naturally occurring red pigments characterized by a common pyrrolylpyrromethene skeleton. Some members of this family have been shown to possess interesting ...immunosuppressive properties exerted with a novel mechanism of action, different from that of currently used drugs. In fact, Ps inhibit phosphorylation and activation of JAK-3, a cytoplasmic tyrosine kinase associated with a cell surface receptor component called common γ-chain, which is exclusive of all IL-2 cytokine family receptors. Blocking common γ-chain transduction activity results in a potent and specific immunosuppressive activity. With respect to the interesting and unexploited immunomodulating properties of this family of compounds we initiated a medicinal chemistry program aimed at finding novel prodigiosin derivatives with improved immunosuppressive activity and lower toxicity. Utilizing an unprecedented and flexible way of assembling the prodigiosin frame, a number of new derivatives have been prepared and tested leading to the choice of 4-benzyloxy-5-(5-undecyl-2H-pyrrol-2-ylidene)methyl-2,2‘-bi-1H-pyrrole (PNU-156804, 16) as a lead immunosuppressant.
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