302 research outputs found
Prejudices towards people with intellectual disabilities: reliability and validity of the Italian Modern and Classical Prejudices Scale
Background
Prejudices and negative attitudes towards intellectual disabilities (IDs) may hinder social inclusion of ID individuals, limiting their well‐being. This study investigated the psychometric characteristics of the Italian Modern and Classical Prejudices Scale (MCPS‐IT) towards people with ID and the effects of gender, age and socio‐economic status (SES) on prejudices.
Method
The MCPS‐IT was administered to 474 adults (69% women, age range 18–70 years, M = 33.13) in conjunction with a questionnaire evaluating socio‐demographic information (SES), the contact and the education about ID people and the social dominance orientation.
Results
Results confirmed that Italian MCPS has a two‐factor structure that measures in a reliable and valid way prejudice towards people with ID. Multivariate analyses of variance confirmed a weak gender difference in both scales and age differences in modern scale. No SES differences were found.
Conclusion
The Italian MCPS represents a valid scale that can be used to monitor the social context of people with ID
Diffusion of a ring polymer in good solution via the Brownian dynamics
Diffusion constants D_{R} and D_{L} of ring and linear polymers of the same
molecular weight in a good solvent, respectively, have been evaluated through
the Brownian dynamics with hydrodynamic interaction. The ratio ,
which should be universal in the context of the renormalization group, has been
estimated as for the large-N limit. It should be consistent
with that of synthetic polymers, while it is smaller than that of DNAs such as
. Furthermore, the probability of the ring polymer being a
nontrivial knot is found to be very small, while bond crossings may occur at
almost all time steps in the present simulation that realizes the good solvent
conditions.Comment: 11 pages, 4 figure
Validation of a capillary zone electrophoresis method for the determination of ciprofloxacin, gatifloxacin, moxifloxacin and ofloxacin in pharmaceutical formulations
An alternative capillary zone electrophoresis (CZE) method for the determination of ciprofloxacin (CPFLX), gatifloxacin (GTFLX), moxifloxacin (MFLX) and ofloxacin (OFLX) through a simple aqueous electrolyte system consisting of 25 mmol L-1 of TRIS/ hydrochloride and 15 mmol L-1 of sodium tetraborate buffer mixture (pH 8.87) using direct UV detection at 282 nm within 3 min was validated. The analytical parameters of validation evaluated were: linearity (r > 0.998), selectivity (comparison between slope of the calibration curve of external standard and calibration curve of standard addition), repeatability in area for sample (RSD%: < 3.94% for CPFLX, < 3.87% for GTFLX, 1.30% for MFLX and < 1.88% for OFLX), intermediate precision in area for sample (RSD%: < 3.59% for CPFLX, < 3.09% for GTFLX, 2.67% for MFLX and < 2.25% for OFLX), accuracy (mean of recovery range: 101.2% for CPFLX, 101.0% for GTFLX, 101.3% for MFLX and 99.9% for OFLX), limit of detection (mg L-1: 2.72 for CPFLX, 1.92 for GTFLX, 0.795 for MFLX and 1.05 for OFLX), limit of quantification (mg L-1: 9.06 for CPFLX, 6.40 for GTFLX, 2.65 for MFLX and 3.50 for OFLX) and robustness. Due to its simplicity, selectivity, precision, accuracy and rapidity, the methodology can be an interesting alternative for quality assurance in the pharmaceutical industry of these drugs
On the size of knots in ring polymers
We give two different, statistically consistent definitions of the length l
of a prime knot tied into a polymer ring. In the good solvent regime the
polymer is modelled by a self avoiding polygon of N steps on cubic lattice and
l is the number of steps over which the knot ``spreads'' in a given
configuration. An analysis of extensive Monte Carlo data in equilibrium shows
that the probability distribution of l as a function of N obeys a scaling of
the form p(l,N) ~ l^(-c) f(l/N^D), with c ~ 1.25 and D ~ 1. Both D and c could
be independent of knot type. As a consequence, the knot is weakly localized,
i.e. ~ N^t, with t=2-c ~ 0.75. For a ring with fixed knot type, weak
localization implies the existence of a peculiar characteristic length l^(nu) ~
N^(t nu). In the scaling ~ N^(nu) (nu ~0.58) of the radius of gyration of the
whole ring, this length determines a leading power law correction which is much
stronger than that found in the case of unrestricted topology. The existence of
such correction is confirmed by an analysis of extensive Monte Carlo data for
the radius of gyration. The collapsed regime is studied by introducing in the
model sufficiently strong attractive interactions for nearest neighbor sites
visited by the self-avoiding polygon. In this regime knot length determinations
can be based on the entropic competition between two knotted loops separated by
a slip link. These measurements enable us to conclude that each knot is
delocalized (t ~ 1).Comment: 29 pages, 14 figure
Design of a high power production target for the Beam Dump Facility at CERN
The Beam Dump Facility (BDF) project is a proposed general-purpose facility
at CERN, dedicated to beam dump and fixed target experiments. In its initial
phase, the facility is foreseen to be exploited by the Search for Hidden
Particles (SHiP) experiment. Physics requirements call for a pulsed 400 GeV/c
proton beam as well as the highest possible number of protons on target (POT)
each year of operation, in order to search for feebly interacting particles.
The target/dump assembly lies at the heart of the facility, with the aim of
safely absorbing the full high intensity Super Proton Synchrotron (SPS) beam,
while maximizing the production of charmed and beauty mesons. High-Z materials
are required for the target/dump, in order to have the shortest possible
absorber and reduce muon background for the downstream experiment. The high
average power deposited on target (305 kW) creates a challenge for heat
removal. During the BDF facility Comprehensive Design Study (CDS), launched by
CERN in 2016, extensive studies have been carried out in order to define and
assess the target assembly design. These studies are described in the present
contribution, which details the proposed design of the BDF production target,
as well as the material selection process and the optimization of the target
configuration and beam dilution. One of the specific challenges and novelty of
this work is the need to consider new target materials, such as a molybdenum
alloy (TZM) as core absorbing material and Ta2.5W as cladding.
Thermo-structural and fluid dynamics calculations have been performed to
evaluate the reliability of the target and its cooling system under beam
operation. In the framework of the target comprehensive design, a preliminary
mechanical design of the full target assembly has also been carried out,
assessing the feasibility of the whole target system.Comment: 17 pages, 18 figure
Meta-heurística Inspirada na Bioluminescência dos Vaga-lumes usando Aprendizagem Baseada em Oposição Elite
A estagnação em ótimo local é um problema frequente dos métodos meta-heurísticos, incluindo os inspirados na natureza como o Algoritmo do Vaga-lume (FA). Embora várias abordagens tenham sido propostas, o problema continua uma questão em aberto. Este trabalho apresenta uma variante do FA que utiliza Aprendizagem Baseada em Oposição Elite (EOBL), denominada FA–EOBL. A variante objetiva gerar diversidade e aumentar a velocidade de convergência do FA original. Diversos experimentos foram realizados com 12 funções de referência. Em geral, elas são usadas para validar e comparar novos algoritmos de otimização. Os resultados mostram a superioridade da FA–EOBL quando ela é comparada com o FA original
Knot localization in adsorbing polymer rings
We study by Monte Carlo simulations a model of knotted polymer ring adsorbing
onto an impenetrable, attractive wall. The polymer is described by a
self-avoiding polygon (SAP) on the cubic lattice. We find that the adsorption
transition temperature, the crossover exponent and the metric exponent
, are the same as in the model where the topology of the ring is
unrestricted. By measuring the average length of the knotted portion of the
ring we are able to show that adsorbed knots are localized. This knot
localization transition is triggered by the adsorption transition but is
accompanied by a less sharp variation of the exponent related to the degree of
localization. Indeed, for a whole interval below the adsorption transition, one
can not exclude a contiuous variation with temperature of this exponent. Deep
into the adsorbed phase we are able to verify that knot localization is strong
and well described in terms of the flat knot model.Comment: 27 pages, 10 figures. Submitter to Phys. Rev.
Selection of elms tolerant to Dutch elm Disease in south-west Romania
Ophoiostoma novo- ulmi continues to be one of the most dangerous invasive fungi, destroying
many autochthonous elm forests and cultures throughout the world. Searching for natural genotypes
tolerant to Dutch Elm Disease (DED) is one of the main objectives of silviculturists all over the
northern hemisphere in order to save the susceptible elms and to restore their ecosystem biodiversity.
In this regard, the first trial was established between 1991 and 1994, in south-west Romania (Padurea
Verde, Timis,
oara), using three elm species (Ulmus minor, U. glabra, and U. laevis) with 38 provenances.
A local strain of Ophiostoma novo-ulmi was used to artificially inoculate all elm variants and the DED
evolution was observed. Furthermore, in 2018–2021 the trial was inventoried to understand the local
genotype reaction to DED in the local environmental conditions after almost 30 years. The outcomes
of the present study proved the continuous presence of the infections in the comparative culture
and its proximity, but the identified pathogen had a new hybrid form (found for the first time in
Romania) between O. novo-ulmi ssp. Americana x O. novo-ulmi ssp. novo-ulmi. Wych elm (U. glabra)
was extremely sensitive to DED: only 12 trees (out of 69 found in 2018) survived in 2021, and only
one tree could be selected according to the adopted health criteria (resistance and vigour). The field
elm (U. minor) was sensitive to the pathogen, but there were still individuals that showed good health
status and growth. In contrast, the European white elm (U. laevis) proved constant tolerance to DED:
only 15% had been found dead or presented severe symptoms of dieback. Overall, the results of
this study report the diverse reactions of the Romanian regional elm genotypes to DED over the last
three decades, providing promising perspectives for improving the presence of elms in the forest
ecosystems of the Carpathian basin
Hamiltonian walks on Sierpinski and n-simplex fractals
We study Hamiltonian walks (HWs) on Sierpinski and --simplex fractals. Via
numerical analysis of exact recursion relations for the number of HWs we
calculate the connectivity constant and find the asymptotic behaviour
of the number of HWs. Depending on whether or not the polymer collapse
transition is possible on a studied lattice, different scaling relations for
the number of HWs are obtained. These relations are in general different from
the well-known form characteristic of homogeneous lattices which has thus far
been assumed to hold for fractal lattices too.Comment: 22 pages, 6 figures; final versio
Abundance of unknots in various models of polymer loops
A veritable zoo of different knots is seen in the ensemble of looped polymer
chains, whether created computationally or observed in vitro. At short loop
lengths, the spectrum of knots is dominated by the trivial knot (unknot). The
fractional abundance of this topological state in the ensemble of all
conformations of the loop of segments follows a decaying exponential form,
, where marks the crossover from a mostly unknotted
(ie topologically simple) to a mostly knotted (ie topologically complex)
ensemble. In the present work we use computational simulation to look closer
into the variation of for a variety of polymer models. Among models
examined, is smallest (about 240) for the model with all segments of the
same length, it is somewhat larger (305) for Gaussian distributed segments, and
can be very large (up to many thousands) when the segment length distribution
has a fat power law tail.Comment: 13 pages, 6 color figure
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