1,457 research outputs found
Pole Dancing: 3D Morphs for Tree Drawings
We study the question whether a crossing-free 3D morph between two
straight-line drawings of an -vertex tree can be constructed consisting of a
small number of linear morphing steps. We look both at the case in which the
two given drawings are two-dimensional and at the one in which they are
three-dimensional. In the former setting we prove that a crossing-free 3D morph
always exists with steps, while for the latter steps
are always sufficient and sometimes necessary.Comment: Appears in the Proceedings of the 26th International Symposium on
Graph Drawing and Network Visualization (GD 2018
On the construction of model Hamiltonians for adiabatic quantum computation and its application to finding low energy conformations of lattice protein models
In this report, we explore the use of a quantum optimization algorithm for
obtaining low energy conformations of protein models. We discuss mappings
between protein models and optimization variables, which are in turn mapped to
a system of coupled quantum bits. General strategies are given for constructing
Hamiltonians to be used to solve optimization problems of
physical/chemical/biological interest via quantum computation by adiabatic
evolution. As an example, we implement the Hamiltonian corresponding to the
Hydrophobic-Polar (HP) model for protein folding. Furthermore, we present an
approach to reduce the resulting Hamiltonian to two-body terms gearing towards
an experimental realization.Comment: 35 pages, 8 figure
Dynamical structure factor of a nonlinear Klein-Gordon lattice
The quantum modes of a nonlinear Klein-Gordon lattice have been computed
numerically [L. Proville, Phys. Rev. B 71, 104306 (2005)]. The on-site
nonlinearity has been found to lead to phonon bound states. In the present
paper, we compute numerically the dynamical structure factor so as to simulate
the coherent scattering cross section at low temperature. The inelastic
contribution is studied as a function of the on-site anharmonicity.
Interestingly, our numerical method is not limited to the weak anharmonicity
and permits one to study thoroughly the spectra of nonlinear phonons
High energy pulse dynamics in multimode GRIN fibers
High energy, ultra-short multimode soliton pulse fission is observed and numerically studied in multimode GRIN fibers, showing complex dynamics bringing to multiple fundamental solitons that do not entirely follow standard single mode soliton perturbation theory predictions
Participatory design of a thematic questionnaire in the field of victimization studies
The paper introduces the results of a two-step process that led to the design of a new questionnaire in the field of victimization studies. A desk-based review of national Crime and Victimization Surveys from five EU countries was performed and resulted in identifying opportunities to improve the consistency among these surveys as well as the need to include more independent variables in order to measure fear of crime and its correlation with sociological variables. Then 12 experts in survey-based measures of crime-related issues were involved in a Delphi panel with the objective of enhancing a participatory design of a new questionnaire addressing individual and space-based determinants of the perception of insecurity, which has been poorly explored to date
Wt-p53 action in human leukaemia cell lines corresponding to different stages of differentiation.
Recent studies support the potential application of the wt-p53 gene in cancer therapy. Expression of exogenous wt-p53 suppresses a variety of leukaemia phenotypes by acting on cell survival, proliferation and/or differentiation. As for tumour gene therapy, the final fate of the neoplastic cells is one of the most relevant points. We examined the effects of exogenous wt-p53 gene expression in several leukaemia cell lines to identify p53-responsive leukaemia. The temperature-sensitive p53Val135 mutant or the human wt-p53 cDNA was transduced in leukaemia cell lines representative of different acute leukaemia FAB subtypes, including M1 (KG1), M2 (HL-60), M3 (NB4), M5 (U937) and M6 (HEL 92.1.7), as well as blast crisis of chronic myelogenous leukaemia (BC-CML: K562, BV173) showing diverse differentiation features. By morphological, molecular and biochemical analyses, we have shown that exogenous wt-p53 gene expression induces apoptosis only in cells corresponding to M1, M2 and M3 of the FAB classification and in BC-CML showing morphological and cytochemical features of undifferentiated blast cells. In contrast, it promotes differentiation in the others. Interestingly, cell responsiveness was independent of the vector used and the status of the endogenous p53 gene
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