Iterated uniform finite-state transducers

A deterministic iterated uniform finite-state transducer (for short, iufst) operates the same length-preserving transduction on several left-to-right sweeps. The first sweep occurs on the input string, while any other sweep processes the output of the previous one. We focus on constant sweep bounded iufsts. We study their descriptional power vs. deterministic finite automata, and the state cost of implementing language operations. Then, we focus on non-constant sweep bounded iufsts, showing a nonregular language hierarchy depending on sweep complexity

Photonic realization of a quantum finite automaton

We describe a physical implementation of a quantum finite automaton that recognizes a well-known family of periodic languages. The realization exploits the polarization degree of freedom of single photons and their manipulation through linear optical elements. We use techniques of confidence amplification to reduce the acceptance error probability of the automaton. It is worth remarking that the quantum finite automaton we physically realize is not only interesting per se but it turns out to be a crucial building block in many quantum finite automaton design frameworks theoretically settled in the literature

Fluoration de l’émail in vitro par laser à rayons ultraviolets

28 samples of human enamel have been studied in order to measure fluoride absorption after treatment with ultraviolet radiations.Samples treated with topical application only presented limited fluoride absorption in enamel surface (up to 0,5 µm deep). The absorption rate was higher, using an U.V. lamp. In samples treated with «excimer» laser, fluoride absorption was much higher in the surface layer and occurred also deeper (3 µm).28 échantillons d’émail dentaire humain ont été analysés afin de quantifier l’absorption du fluor après traitement aux rayons ultraviolets.Les analyses ont montré que les échantillons soumis à une simple application topique présentent une absorption de fluor modeste, uniquement dans les couches superficielles de l’émail (jusqu’à 0,5 µm de profondeur). L’absorption est plus importante en utilisant une lampe à vapeur de mercure. Avec le laser «excimer», comparé aux deux autres méthodes, la fixation du fluor dans le réseau de l’émail est très supérieure en surface et se produit également en profondeur (3 µm)

Rôle de la stabilométrie dans l’évaluation des corrélations entre les troubles crânio-mandibulaires (TCM) et les troubles de l’équilibre (TE)

We examined three groups:- 29 patients suffering from balance disorders and craniomandibular disorders but not from vestibular disease;- 21 patients suffering from balance disorders, craniomandibular disorders and vestibular disease;- 26 patients suffering from craniomandibular disorders but not from vestibular disease or balance sorders.All cases were examined by the odontologist and otoneurologist and tested by computerized stabilometry; they were reexamined after six months of therapy by an occlusal stabilization splint. The static analysis of the results shows a significative reduction of the postural oscillations in all patients.Trois groupes de patients ont été examinés :- 29 sujets présentant des TE et des TCM sans vestibulopathie;- 21 sujets présentant des TE et des TCM associés à une vestibulopathie;- 26 sujets avec TCM sans TE ni vestibulopathie.Après une visite odontologique et otoneurologique complétée par une stabilométrie assistée par ordinaeur, les 3 groupes ont tous été recontrôlés après 6 mois de thérapie avec plaque de stabilisation. L’analyse les données a permis de constater une réduction significative des oscillations posturales chez tous les patients

L’emploi de la stabilométrie assistée par ordinateur dans le diagnostic des troubles crânio-mandibulaires (TCM)

The aim of this study was to evaluate the influence of the cervical region and the stomatognatic system on the balance control. We examined 35 healthy subjects and 201 balance disorder patients; of the 201 patients 60 suffered also from craniomandibular disorders (CMD) and 40 from cervical rachis disease. All cases were tested by computerized stabilometry executed in Romberg position: with closed eyes, retroflexed head and two cotton roles between the dental archs. The results show that cervical rachis disease and stomatognatic dysfunction have a significative influence on the balance control; however, this influence is smaller than that of vestibular disease; moreover, the computer stabilometry allows to measure the degree of ascending or descending correlation between the posture and stomatognatic system.Le but de cette étude a été d’évaluer l’influence de la région cervicale et de l’appareil stomatognatique sur le contrôle postural. On a examiné 35 sujets normaux et 201 patients avec troubles de l’équilibre, dont 60 présentaient aussi des troubles cranio-mandibulaires (TCM) et 40 une pathologie du rachis cervical. Tous les patients ont été soumis à un examen stabilométrique assisté par ordinateur, effectué en position de Romberg: les yeux fermés, la tête en rétroflexion, en occlusion modifiée par rouleaux interdentaires. Les résultats indiquent que les pathologies du rachis cervical et celles de l’appareil stomatognatique ont une influence significative sur le contrôle postural; toutefois, cette influence est nettement inférieure à celle des pathologies vestibulaires. Ils montrent également que la stabilométrie permet de mesurer le degré de corrélation ascendant ou descendant entre la posture et l’appareil stomatognatique

Study of the reaction pbar p -> phi phi from 1.1 to 2.0 GeV/c

A study has been performed of the reaction pbar p -> 4K using in-flight antiprotons from 1.1 to 2.0 GeV/c incident momentum interacting with a hydrogen jet target. The reaction is dominated by the production of a pair of phi mesons. The pbar p -> phi phi cross section rises sharply above threshold and then falls continuously as a function of increasing antiproton momentum. The overall magnitude of the cross section exceeds expectations from a simple application of the OZI rule by two orders of magnitude. In a fine scan around the xi/f_J(2230) resonance, no structure is observed. A limit is set for the double branching ratio B(xi -> pbar p) * B(xi -> phi phi) < 6e-5 for a spin 2 resonance of M = 2.235 GeV and Width = 15 MeV.Comment: 13 pages, 13 figures, 2 tables, Latex. To be published in Phys. Rev.

A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)

We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data sample consists of 29.7 ${\rm fb}^{-1}$ recorded at the $\Upsilon(4S)$ resonance and 3.9 ${\rm fb}^{-1}$ off-resonance. One of the neutral B mesons, which are produced in pairs at the $\Upsilon(4S)$, is fully reconstructed in the CP decay modes $J/\psi K^0_S$, $\psi(2S) K^0_S$, $\chi_{c1} K^0_S$, $J/\psi K^{*0}$ ($K^{*0}\to K^0_S\pi^0$) and $J/\psi K^0_L$, or in flavor-eigenstate modes involving $D^{(*)}\pi/\rho/a_1$ and $J/\psi K^{*0}$ ($K^{*0}\to K^+\pi^-$). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. A maximum-likelihood fit to this flavor eigenstate sample finds $\Delta m_d = 0.516\pm 0.016 {\rm (stat)} \pm 0.010 {\rm (syst)} {\rm ps}^{-1}$. The value of the asymmetry amplitude $\sin2\beta$ is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged $B^0$ decays in the CP-eigenstate modes. We find $\sin2\beta=0.59\pm 0.14 {\rm (stat)} \pm 0.05 {\rm (syst)}$, demonstrating that CP violation exists in the neutral B meson system. (abridged)Comment: 58 pages, 35 figures, submitted to Physical Review