11,020 research outputs found
Construction Of A Rich Word Containing Given Two Factors
A finite word with contains at most distinct
palindromic factors. If the bound is attained, the word is called
\emph{rich}. Let \Factor(w) be the set of factors of the word . It is
known that there are pairs of rich words that cannot be factors of a common
rich word. However it is an open question how to decide for a given pair of
rich words if there is a rich word such that \{u,v\}\subseteq
\Factor(w). We present a response to this open question:\\ If are
rich words, , and
\{w_1,w_2\}\subseteq \Factor(w) then there exists also a rich word
such that \{w_1,w_2\}\subseteq \Factor(\bar w) and , where and is the size
of the alphabet. Hence it is enough to check all rich words of length equal or
lower to in order to decide if there is a rich word containing
factors
Spectral properties of incommensurate charge-density wave systems
The concept of frustrated phase separation is applied to investigate its
consequences for the electronic structure of the high T_c cuprates. The
resulting incommensurate charge density wave (CDW) scattering is most effective
in creating local gaps in k-space when the scattering vector connects states
with equal energy. Starting from an open Fermi surface we find that the
resulting CDW is oriented along the (10)- and (or) (01)-direction which allows
for a purely one-dimensional or a two-dimensional ``eggbox type'' charge
modulation. In both cases the van Hove singularities are substantially
enhanced, and the spectral weight of Fermi surface states near the M-points,
tends to be suppressed. Remarkably, a leading edge gap arises near these
points, which, in the eggbox case, leaves finite arcs of the Fermi surface
gapless. We discuss our results with repect to possible consequences for
photoemission experiments
On the Number of Closed Factors in a Word
A closed word (a.k.a. periodic-like word or complete first return) is a word
whose longest border does not have internal occurrences, or, equivalently,
whose longest repeated prefix is not right special. We investigate the
structure of closed factors of words. We show that a word of length
contains at least distinct closed factors, and characterize those words
having exactly closed factors. Furthermore, we show that a word of length
can contain many distinct closed factors.Comment: Accepted to LATA 201
Measles in Italy: Viral strains and crossing borders.
In 2017, Italy experienced one of the largest outbreaks of measles in recent years, with 5404 notified cases and 4347 confirmed cases. A further 2029 cases were notified during the first 6 months of 2018, and 1516 of them were laboratory-confirmed. The B3 and D8 genotypes were identified as those responsible for the outbreak. Possible transmission routes can be established by monitoring the circulating measles virus strains in support of the national health authorities to warn people and travellers
Application of Nonredundant Sampling Representations of Electromagnetic Fields to NF-FF Transformation Techniques
An overview of the application of the band-limitation properties and nonredundant sampling representations of electromagnetic fields to NF-FF transformations is presented. The progresses achieved by applying them to data acquired on conventional NF scanning surfaces are discussed, outlining the remarkable reduction in the number of needed NF samples and measurement time. An optimal sampling interpolation expansion for reconstructing the probe response on a rotational scanning surface from a non-redundant number of its samples is also discussed. A unified theory of the NF-FF transformations with spiral scannings, which allow a remarkable reduction of the measurement time, is then reviewed by describing a sampling representation of the voltage on a quite arbitrary rotational surface from its nonredundant samples collected on a proper spiral wrapping it. Some numerical and experimental results assessing the effectiveness of the considered NF-FF transformations are shown too
Monte Carlo evaluation of the external gamma, neutron and muon induced background sources in the CUORE experiment
CUORE is a 1 ton scale cryogenic experiment aiming at the measurement of the
Majorana mass of the electron neutrino. The detector is an array of 988 TeO2
bolometers used for a calorimetric detection of the two electrons emitted in
the BB0n of 130Te. The sensitivity of the experiment to the lowest Majorana
mass is determined by the rate of background events that can mimic a BB0n. In
this paper we investigate the contribution of external sources i.e.
environmental gammas, neutrons and cosmic ray muons to the CUORE background and
show that the shielding setup designed for CUORE guarantees a reduction of this
external background down to a level <1.0E-02 c/keV/kg/y at the Q-value, as
required by the physical goal of the experiment.Comment: 14 pages, 7 figure
Nitric oxide and hydrogen sulfide: the gasotransmitter paradigm of the vascular system.
There are several reviews on NO and hydrogen sulfide (H2 S) and their role in vascular diseases in the current relevant literature. The aim of this review is to discuss, within the limits of present knowledge, the interconnection between these two gasotransmitters in vascular function. In particular, the review focuses on the role played by the balance between the NO and H2 S pathways in either physiological or pathological conditions. The distinction between physiology and pathology has been made in order to dissect the molecular basis of this crosstalk, highlighting how and if this balance varies, depending upon the vascular status. Perspectives and possible novel therapeutic approaches are also discussed
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