On characterizing game-perfect graphs by forbidden induced subgraphs

A graph $G$ is called $g$-perfect if, for any induced subgraph $H$ of $G$, the game chromatic number of $H$ equals the clique number of $H$. A graph $G$ is called $g$-col-perfect if, for any induced subgraph $H$ of $G$, the game coloring number of $H$ equals the clique number of $H$. In this paper we characterize the classes of $g$-perfect resp. $g$-col-perfect graphs by a set of forbidden induced subgraphs and explicitly. Moreover, we study similar notions for variants of the game chromatic number, namely $B$-perfect and $[A,B]$-perfect graphs, and for several variants of the game coloring number, and characterize the classes of these graphs

Evaluation of Angiogenic Factor Release From Thermosensitive Poly N-Vinylcaprolactam -g-Collagen: In Vitro and In Vivo Studies

I n this study, a thermosensitive poly N-vinylcaprolactam -g-collagen PNVCL-g-Col hybrid hydrogel was synthesized by conjugation using the NHS/EDC cross-linking system, and characterized. At first, the efficiency of in vitro sustained delivery of human vascular endothelial growth factor VEGF from the thermosensitive PNVCL-g-Col hydrogel modified with heparin, was evaluated for duration of ten days under in vitro physiological conditions 37oC, pH 7.4 . The results indicated that PNVCL-g-Col hydrogel preserved its stability and released ~90% of the loaded VEGF within this time period. In vitro study showed that PNVCL-g-Col was basically histocompatible. Then, the in vivo angiogenic activity of the VEGF-releasing PNVCL-g-Col was investigated using a subcutaneous rat model. In vivo study confirmed that angiogenic-factor-loaded PNVCL-g-Col had the capacity to induce neovascularization indicating that the in vivo bioactivity of the VEGF was preserved in the thermosensitive PNVCL-g-Co

Harmonic Potential Theorem: Extension to Spin-, Velocity-, and Density-Dependent Interactions

One of the few exact results for the description of the time evolution of an inhomogeneous, interacting many-particle system is given by the harmonic potential theorem (HPT). The relevance of this theorem is that it sets a tight constraint on time-dependent many-body approximations. In this contribution, we show that the original formulation of the HPT is valid also for the case of spin-, velocity-, and density-dependent interactions. This result is completely general and relevant, among the rest, for nuclear structure theory both in the case of ab initio and of more phenomenological approaches. As an example, we report on a numerical implementation by testing the small-amplitude limit of the time-dependent Hartree-Fock-also known as the random phase approximation-for the translational frequencies of a neutron system trapped in a harmonic potential

Travaux linguistiques du CerLiCO 16 « Morphosyntaxe du lexique 2 : Catégorisation et mise en discours »

Le volume 16 des Travaux Linguistiques du CERLICO, Morphosyntaxe du lexique 2 ; Catégorisation et mise en discours, édité par G. Col et J.-P. Régis, rassemble les actes du colloque organisé par le Cerlico les 8 et 9 juin 2002 à l’Université François Rabelais de Tours. L’objet d’étude choisi, le lexique et ses composantes, est en effet le lieu où se cristallisent différents problèmes en terme de catégorisation. Il est abordé en 3 parties, présentées par G. Col dans la préface de l’ouvrage. On ..

Continuum particle-vibration coupling method in coordinate-space representation for finite nuclei

In this paper we present a new formalism to implement the nuclear particle-vibration coupling (PVC) model. The key issue is the proper treatment of the continuum that is allowed by the coordinate space representation. Our formalism, based on the use of zero-range interactions such as the Skyrme forces, is microscopic and fully self-consistent. We apply it to the case of neutron single-particle states in Ca-40, Pb-208, and O-24. The first two cases are meant to illustrate the comparison with the usual (i.e., discrete) PVC model. However, we stress that the present approach allows one to calculate properly the effect of PVC on resonant states. We compare our results with those from experiments in which the particle transfer in the continuum region has been attempted. The latter case, namely O-24, is chosen as an example of a weakly-bound system. Such a nucleus, being double magic and not displaying collective low-lying vibrational excitations, is characterized by quite pure neutron single-particle states around the Fermi surface

Hybrid configuration mixing model for odd nuclei

In this work, we introduce a new approach which is meant to be a first step towards complete self-consistent low-lying spectroscopy of odd nuclei. So far, we essentially limit ourselves to the description of a double-magic core plus an extra nucleon. The model does not contain any free adjustable parameter and is instead based on a Hartree-Fock (HF) description of the particle states in the core, together with self-consistent random-phase approximation (RPA) calculations for the core excitations. We include both collective and noncollective excitations, with proper care of the corrections due to the overlap between them (i.e., due to the nonorthonormality of the basis). As a consequence, with respect to traditional particle-vibration coupling calculations in which one can only address single-nucleon states and particle-vibration multiplets, we can also describe states of shell-model types like 2 particle-1 hole. We will report results for Ca49 and Sb133 and discuss future perspectives

Determining the Full-Length Structure of Collagenase H using Small-Angle X-ray Scattering

Known to cause gas gangrene, Hathewaya histolytica secretes two sister collagenases, collagenase G (Col G) and collagenase H (Col H), to degrade the triple helical structure of collagen to further infection in a host. Individual domains of Col H have been crystalized in previous studies, but methods in x-ray crystallization of full-length Col H have been unsuccessful. Using Small Angle X-Ray Scattering (SAXS) data, atomistic modeling was used to generate multiple conformations of Col H while accounting for flexibility between domains. Full-length Col H was found to adopt a two-state conformational model exhibiting a majority compact and a minority elongated form regardless of calcium concentration. This suggests Col H may become more flexible in lower calcium concentrations but does not elongate as previously suspected. Determination of full-length Col H could significantly impact drug delivery design and therapeutic agents concerning procedures such as skin debridement and pancreatic islet extraction