Identifying DsJ(2700)D_{sJ}(2700) through its decay modes

We study how to assign the recently observed $D_{sJ}(2700)$ meson to an appropriate level of the $c \bar s$ spectrum by the analysis of its decay modes in final states comprising a light pseudoscalar meson. We use an effective lagrangian approach with heavy quark and chiral symmetries, obtaining that the measurement of the $D^* K$ decay width would allow to distinguish between two possible assignments.Comment: RevTex, 6 pages - references adde

Auralization of Amplitude Modulated Helicopter Flyover Noise

Rotorcraft noise is an active field of study as the sound produced by these vehicles is often found to be annoying. A means to auralize rotorcraft flyover noise is sought to help understand the factors leading to annoyance. Previous work by the authors auralized a complete flyover event in which the source noise synthesis traversed a range of emission angles. The source noise definition process for the synthesis used helicopter flyover recordings. Although this process yielded both periodic and aperiodic (modulation) components at a set of discrete emission angles, only the periodic components were used in the previous work to synthesize the sound of the flyover event. In the current work, aperiodic amplitude modulation is incorporated into the source noise synthesis to improve its fidelity toward assessing rotorcraft noise annoyance. The method is demonstrated using ground recordings from a flight test of the AS350 helicopter for the source noise definition

A direct kinematical derivation of the relativistic Sagnac effect for light or matter beams

The Sagnac time delay and the corresponding Sagnac phase shift, for relativistic matter and electromagnetic beams counter-propagating in a rotating interferometer, are deduced on the ground of relativistic kinematics. This purely kinematical approach allows to explain the ''universality'' of the effect, namely the fact that the Sagnac time difference does not depend on the physical nature of the interfering beams. The only prime requirement is that the counter-propagating beams have the same velocity with respect to any Einstein synchronized local co-moving inertial frame.Comment: 10 pages, 1 EPS figure, to appear in General Relativity and Gravitatio

The pseudomorphic to bulk fcc phase transition of thin Ni films on Pd(100)

We have measured the transformation of pseudomorphic Ni films on Pd(100) into their bulk fcc phase as a function of the film thickness. We made use of x-ray diffraction and x-ray induced photoemission to study the evolution of the Ni film and its interface with the substrate. The growth of a pseudomorphic film with tetragonally strained face centered symmetry (fct) has been observed by out-of-plane x-ray diffraction up to a maximum thickness of 10 Ni layers (two of them intermixed with the substrate), where a new fcc bulk-like phase is formed. After the formation of the bulk-like Ni domains, we observed the pseudomorphic fct domains to disappear preserving the number of layers and their spacing. The phase transition thus proceeds via lateral growth of the bulk-like phase within the pseudomorphic one, i.e. the bulk-like fcc domains penetrate down to the substrate when formed. This large depth of the walls separating the domains of different phases is also indicated by the strong increase of the intermixing at the substrate-film interface, which starts at the onset of the transition and continues at even larger thickness. The bulk-like fcc phase is also slightly strained; its relaxation towards the orthomorphic lattice structure proceeds slowly with the film thickness, being not yet completed at the maximum thickness presently studied of 30 Angstrom (i.e. about 17 layers).Comment: 8 pages, 7 figure

Locality hypothesis and the speed of light

The locality hypothesis is generally considered necessary for the study of the kinematics of non-inertial systems in special relativity. In this paper we discuss this hypothesis, showing the necessity of an improvement, in order to get a more clear understanding of the various concepts involved, like coordinate velocity and standard velocity of light. Concrete examples are shown, where these concepts are discussed.Comment: 23 page

Formaldehyde solutions in simulated sweat increase human melanoma but not normal human keratinocyte cells proliferation

Our skin is in close contact with clothes most of the time thus risking potentially noxious chemicals contact. One of the potentially harmful manufacturing by-products that can be released by textiles when sweating is formaldehyde, used as an anti-crease treatment. As it is known to be carcinogenic to humans and a potent skin sensitizer, the aim of this study was to investigate its effects on both normal human keratinocytes (HaCaT cells) and on a highly invasive malignant melanoma cell line (SK-MEL-28) in order to contribute to the definition of safety cut-off to be applied to the production processes. Formaldehyde concentrations below the commonly accepted limits (10\u201350 \u3bcM) were obtained by diluting formaldehyde in simulated sweat (UNI EN ISO 105-E04). The effects on cell proliferation were evaluated by cell counting, while ERK pathway activation was evaluated by western blot. Low concentrations of formaldehyde (10 \u3bcM) in both acidic and alkaline simulated sweat were able to increase malignant melanoma cell proliferation, while not affecting normal keratinocytes. Melanoma proliferation increase was greater in acidic (pH = 5.5) than in alkaline (pH = 8) conditions. Moreover, formaldehyde stimulation was able to induce ERK pathway activation. The data obtained suggest the need for an even increasing attention to the potentially harmful effects of textile manufacturing by-products

Reference frames and rigid motions in relativity: Applications

The concept of rigid reference frame and of constricted spatial metric, given in the previous work [\emph{Class. Quantum Grav.} {\bf 21}, 3067,(2004)] are here applied to some specific space-times: In particular, the rigid rotating disc with constant angular velocity in Minkowski space-time is analyzed, a new approach to the Ehrenfest paradox is given as well as a new explanation of the Sagnac effect. Finally the anisotropy of the speed of light and its measurable consequences in a reference frame co-moving with the Earth are discussed.Comment: 13 pages, 1 figur

Maximum weight cycle packing in directed graphs, with application to kidney exchange programs

Centralized matching programs have been established in several countries to organize kidney exchanges between incompatible patient-donor pairs. At the heart of these programs are algorithms to solve kidney exchange problems, which can be modelled as cycle packing problems in a directed graph, involving cycles of length 2, 3, or even longer. Usually, the goal is to maximize the number of transplants, but sometimes the total benefit is maximized by considering the differences between suitable kidneys. These problems correspond to computing cycle packings of maximum size or maximum weight in directed graphs. Here we prove the APX-completeness of the problem of finding a maximum size exchange involving only 2-cycles and 3-cycles. We also present an approximation algorithm and an exact algorithm for the problem of finding a maximum weight exchange involving cycles of bounded length. The exact algorithm has been used to provide optimal solutions to real kidney exchange problems arising from the National Matching Scheme for Paired Donation run by NHS Blood and Transplant, and we describe practical experience based on this collaboration