4,551 research outputs found
Note about a second "evidence" for a WIMP annual modulation
This note, with its five questions, is intended to contribute to a
clarification about a claimed "evidence" by the DAMA group of an annual
modulation of the counting rate of a Dark Matter NaI(Tl) detector as due to a
neutralino (SUSY-LSP) Dark Matter candidate.Comment: LaTex, 3 pages, 2 figure
Single spin measurement using cellular automata techniques
We propose an approach for single spin measurement. Our method uses
techniques from the theory of quantum cellular automata to correlate a large
amount of ancillary spins to the one to be measured. It has the distinct
advantage of being efficient, and to a certain extent fault-tolerant. Under
ideal conditions, it requires the application of only order of cube root of N
steps (each requiring a constant number of rf pulses) to create a system of N
correlated spins. It is also fairly robust against pulse errors, imperfect
initial polarization of the ancilla spin system, and does not rely on
entanglement. We study the scalability of our scheme through numerical
simulation.Comment: Submitted to Physical Review Letter
Engineering 4.0 to Improve the Safety of Plant Operators in a Metalworking Company of International Importance: The Ansaldo Energia Case
The paper describes how a multidisciplinary team has developed, on behalf of Ansaldo Energia Spa, a methodology based on the technologies made available by Industry 4.0; a methodology that allows rescue teams to quickly intervene in the event of man-down in isolated areas of the plant where the unfortunate person would risk being found with significant delay and consequent problems for his physical well-being. To achieve this result, an appropriate hardware and software device has been developed by a highly specialized supplier, under the direction of the team. Such a device makes it possible to alert automatically rescue teams in real-time, at the occurrence of the event, and geo-locate, with extreme precision, the man on the ground. The methodology, once devised, has been standardized in a series of sequential and generalized steps, in order to make it applicable to any type of company or construction site, or workshop in which the event of the man-down may occur. The methodology is configured as a real toolkit for the protection of operators from damage, even extreme, that can derive from prolonged waits of the rescue teams, each time that operators incur negative events for their safety, whether they are exogenous (illnesses with fainting, heart attacks, epileptic attacks, strokes...) and endogenous (accidents in the workplace)
Erythrocyte's aging in microgravity highlights how environmental stimuli shape metabolism and morphology
The determination of the function of cells in zero-gravity conditions is a subject of interest in many different research fields. Due to their metabolic unicity, the characterization of the behaviour of erythrocytes maintained in prolonged microgravity conditions is of particular importance. Here, we used a 3D-clinostat to assess the microgravity-induced modifications of the structure and function of these cells, by investigating how they translate these peculiar mechanical stimuli into modifications, with potential clinical interest, of the biochemical pathways and the aging processes. We compared the erythrocyte's structural parameters and selected metabolic indicators that are characteristic of the aging in microgravity and standard static incubation conditions. The results suggest that, at first, human erythrocytes react to external stimuli by adapting their metabolic patterns and the rate of consumption of the cell resources. On longer timeframes, the cells translate even small differences in the environment mechanical solicitations into structural and morphologic features, leading to distinctive morphological patterns of agin
Interface bonding of a ferromagnetic/semiconductor junction : a photoemission study of Fe/ZnSe(001)
We have probed the interface of a ferromagnetic/semiconductor (FM/SC)
heterojunction by a combined high resolution photoemission spectroscopy and
x-ray photoelectron diffraction study. Fe/ZnSe(001) is considered as an example
of a very low reactivity interface system and it expected to constitute large
Tunnel Magnetoresistance devices. We focus on the interface atomic environment,
on the microscopic processes of the interface formation and on the iron
valence-band. We show that the Fe contact with ZnSe induces a chemical
conversion of the ZnSe outermost atomic layers. The main driving force that
induces this rearrangement is the requirement for a stable Fe-Se bonding at the
interface and a Se monolayer that floats at the Fe growth front. The released
Zn atoms are incorporated in substitution in the Fe lattice position. This
formation process is independent of the ZnSe surface termination (Zn or Se).
The Fe valence-band evolution indicates that the d-states at the Fermi level
show up even at submonolayer Fe coverage but that the Fe bulk character is only
recovered above 10 monolayers. Indeed, the Fe 1-band states,
theoretically predicted to dominate the tunneling conductance of Fe/ZnSe/Fe
junctions, are strongly modified at the FM/SC interface.Comment: 23 pages, 5 figures, submitted to Physical review
The social cost of rheumatoid arthritis in Italy: the results of an estimation exercise.
The objective of this study is to estimate the mean annual social cost per adult person and the total social cost of rheumatoid arthritis (RA) in Italy. A literature review was performed by searching primary economic studies on adults in order to collect cost data of RA in Italy in the last decade. The review results were merged with data of institutional sources for estimating - following the methodological steps of the cost of illness analysis - the social cost of RA in Italy. The mean annual social cost of RA was € 13,595 per adult patient in Italy. Affecting 259,795 persons, RA determines a social cost of € 3.5 billions in Italy. Non-medical direct cost and indirect cost represent the main cost items (48% and 31%) of the total social cost of RA in Italy. Based on these results, it appears evident that the assessment of the economic burden of RA solely based on direct medical costs evaluation gives a limited view of the phenomenon
Optimal phase estimation in quantum networks
We address the problem of estimating the phase phi given N copies of the
phase rotation u(phi) within an array of quantum operations in finite
dimensions. We first consider the special case where the array consists of an
arbitrary input state followed by any arrangement of the N phase rotations, and
ending with a POVM. We optimise the POVM for a given input state and fixed
arrangement. Then we also optimise the input state for some specific cost
functions. In all cases, the optimal POVM is equivalent to a quantum Fourier
transform in an appropriate basis. Examples and applications are given.Comment: 9 pages, 2 figures; this is an extended version of
arXiv:quant-ph/0609160. v2: minor corrections in reference
- …