Universality in percolation of arbitrary Uncorrelated Nested Subgraphs

The study of percolation in so-called {\em nested subgraphs} implies a generalization of the concept of percolation since the results are not linked to specific graph process. Here the behavior of such graphs at criticallity is studied for the case where the nesting operation is performed in an uncorrelated way. Specifically, I provide an analyitic derivation for the percolation inequality showing that the cluster size distribution under a generalized process of uncorrelated nesting at criticality follows a power law with universal exponent $\gamma=3/2$. The relevance of the result comes from the wide variety of processes responsible for the emergence of the giant component that fall within the category of nesting operations, whose outcome is a family of nested subgraphs.Comment: 5 pages, no figures. Mistakes found in early manuscript have been remove

Intellectual Property, Open Science and Research Biobanks

In biomedical research and translational medicine, the ancient war between exclusivity (private control over information) and access to information is proposing again on a new battlefield: research biobanks. The latter are becoming increasingly important (one of the ten ideas changing the world, according to Time magazine) since they allow to collect, store and distribute in a secure and professional way a critical mass of human biological samples for research purposes. Tissues and related data are fundamental for the development of the biomedical research and the emerging field of translational medicine: they represent the “raw material” for every kind of biomedical study. For this reason, it is crucial to understand the boundaries of Intellectual Property (IP) in this prickly context. In fact, both data sharing and collaborative research have become an imperative in contemporary open science, whose development depends inextricably on: the opportunities to access and use data, the possibility of sharing practices between communities, the cross-checking of information and results and, chiefly, interactions with experts in different fields of knowledge. Data sharing allows both to spread the costs of analytical results that researchers cannot achieve working individually and, if properly managed, to avoid the duplication of research. These advantages are crucial: access to a common pool of pre-competitive data and the possibility to endorse follow-on research projects are fundamental for the progress of biomedicine. This is why the "open movement" is also spreading in the biobank's field. After an overview of the complex interactions among the different stakeholders involved in the process of information and data production, as well as of the main obstacles to the promotion of data sharing (i.e., the appropriability of biological samples and information, the privacy of participants, the lack of interoperability), we will firstly clarify some blurring in language, in particular concerning concepts often mixed up, such as “open source” and “open access”. The aim is to understand whether and to what extent we can apply these concepts to the biomedical field. Afterwards, adopting a comparative perspective, we will analyze the main features of the open models – in particular, the Open Research Data model – which have been proposed in literature for the promotion of data sharing in the field of research biobanks. After such an analysis, we will suggest some recommendations in order to rebalance the clash between exclusivity - the paradigm characterizing the evolution of intellectual property over the last three centuries - and the actual needs for access to knowledge. We argue that the key factor in this balance may come from the right interaction between IP, social norms and contracts. In particular, we need to combine the incentives and the reward mechanisms characterizing scientific communities with data sharing imperative

Study of Charmless Hadronic B Meson Decays to Pseudoscalar-Vector Final States

We report results of searches for charmless hadronic B meson decays to pseudoscalar(pi^+-,K^+-,Pi^0 or Ks^0)-vector(Rho, K* or Omega) final states. Using 9.7 million BBbar pairs collected with the CLEO detector, we report first observation of B^- --> Pi^-Rho^0, B^0 --> Pi^+-Rho^-+ and B^- --> Pi^-Omega, which are expected to be dominated by hadronic b --> u transitions. The measured branching fractions are (10.4+3.3-3.4+-2.1)x10^-6, (27.6+8.4-7.4+-4.2)x10^-6 and (11.3+3.3-2.9+-1.4)x10^-6, respectively. Branching fraction upper limits are set for all the other decay modes investigated.Comment: 10 pages postscript, also available through http://w4.lns.cornell.edu/public/CLN

Study of exclusive two-body B0 meson decays to charmonium

We present a study of three B0 decay modes useful for time-dependent CP asymmetry measurements. From a sample of 9.7 million B meson pairs collected with the CLEO detector, we have reconstructed B0 -> J/psi K0S, B0 -> chi_c1 K0S, and B0 -> J/psi pi0 decays. The latter two decay modes have been observed for the first time. We describe a K0S -> pi0 pi0 detection technique and its application to the reconstruction of the decay B0 -> J/psi K0S. Combining the results obtained using K0S -> pi+ pi- and K0S -> pi0 pi0 decays, we determine Br(B0 -> J/psi K0) = (9.5 +- 0.8 +- 0.6)*10^-4, where the first uncertainty is statistical and the second one is systematic. We also obtain Br(B0 -> chi_c1 K0)= (3.9 +1.9/-1.3 +- 0.4)*10^-4 and Br(B0 -> J/psi pi0) = (2.5 +1.1/-0.9 +- 0.2)*10^-5.Comment: 11 pages, 2 figures, submitted to Phys. Rev.

Limit on Tau Neutrino Mass from τ−→π−π+π−π0ντ\tau^{-}\to \pi^{-}\pi^{+}\pi^{-}\pi^{0}\nu_{\tau}

From a data sample of 29058 $\tau^\pm\to\pi^\pm\pi^+\pi^-\pi^0\nu_\tau$ decays observed in the CLEO detector we derive a 95% confidence upper limit on the tau neutrino mass of 28 MeV.Comment: 17 pages postscript, also available through http://w4.lns.cornell.edu/public/CLN

Hadronic Structure in the Decay τ−→π−π0ντ\tau^{-}\to \pi^{-}\pi^{0}\nu_{\tau}

We report on a study of the invariant mass spectrum of the hadronic system in the decay tau- -> pi- pi0 nu_tau. This study was performed with data obtained with the CLEO II detector operating at the CESR e+ e- collider. We present fits to phenomenological models in which resonance parameters associated with the rho(770) and rho(1450) mesons are determined. The pi- pi0 spectral function inferred from the invariant mass spectrum is compared with data on e+ e- -> pi+ pi- as a test of the Conserved Vector Current theorem. We also discuss the implications of our data with regard to estimates of the hadronic contribution to the muon anomalous magnetic moment.Comment: 39 pages postscript, also available through http://w4.lns.cornell.edu/public/CLN

Search for Baryon and Lepton Number Violating Decays of the τ\tau Lepton

We have searched for five decay modes of the tau lepton that simultaneously violate lepton and baryon number: tau -> anti-proton gamma, tau -> anti-proton pi0, tau -> anti-proton eta, tau -> anti-proton 2pi0, and tau -> anti-proton pi0eta. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR). The integrated luminosity of the data sample is 4.7 fb^{-1}, corresponding to the production of 4.3 x 10^6 tau+tau- events. No evidence is found for any of the decays, resulting in much improved upper limits on the branching fractions for the two-body decays and first upper limits for the three-body decays.Comment: 8 pages, postscript file also available through http://w4.lns.cornell.edu/public/CLN

Resonant Structure of τ→3ππ0ντ\tau\to 3\pi\pi^{0}\nu_{\tau} and τ→ωπντ\tau\to \omega\pi\nu_{\tau} Decays

The resonant structure of the four pion final state in the decay $\tau \to 3\pi\pi^0\nu_\tau$ is analyzed using 4.27 million $\tau^+\tau^-$ pairs collected by the CLEO II experiment. We search for second class currents in the decay $\tau \to \omega\pi\nu_\tau$ using spin-parity analysis and establish an upper limit on the non-vector current contribution. The mass and width of the $\rho'$ resonance are extracted from a fit to the $\tau \to \omega\pi\nu_\tau$ spectral function. A partial wave analysis of the resonant structure of the $\tau \to 3\pi\pi^0\nu_\tau$ decay is performed; the spectral decomposition of the four pion system is dominated by the $\omega\pi$ and $a_1 \pi$ final states.Comment: 34 pages postscript, also available through http://w4.lns.cornell.edu/public/CLN

Study of Exclusive Radiative B Meson Decays

We have investigated exclusive, radiative B meson decays to charmless mesons (\rho, \omega, \phi, K^*(892), K^*_2(1430)) in 9.7\times 10^6 BBbar decays accumulated with the CLEO detector. The B -> K^*(892)\gamma branching fractions are determined to be Br(B^0 -> K^{*0}(892)\gamma) = (4.55 +0.72-0.68 +-0.34)\times 10^-5 and Br(B^+ -> K^{*+}(892)\gamma) = (3.76 +0.89-0.83 +-0.28)\times 10^-5. We have searched for CP asymmetry in B -> K^*(892)\gamma decays and measure Acp = +0.08 +-0.13 +-0.03. We also report the first observation of the decay B -> K^*_2(1430)\gamma with a branching fraction of (1.66 +0.59-0.53 +-0.13)\times 10^-5 and determine $Br(B -> K^*_2(1430)\gamma)/Br(B -> K^*(892)\gamma) = 0.39 +0.15-0.13 consistent with only one of two available theoretical models. No significant evidence for the decays B -> \rho\gamma and B^0 -> \omega\gamma is found and we limit Br(B -> (\rho/\omega)\gamma)/Br(B -> K^{*}(892)\gamma) < 0.32 at 90% CL. We also find no evidence for the exotic decay B^0 -> \phi\gamma.Comment: 12 pages, 3 figures, submitted to Phys. Rev. Letter