12,422 research outputs found
Stretched Polymers in Random Environment
We survey recent results and open questions on the ballistic phase of
stretched polymers in both annealed and quenched random environments.Comment: Dedicated to Erwin Bolthausen on the occasion of his 65th birthda
Displasia glenoidea bilateral dolorosa asociada a inestabilidad
La hipoplasia glenoidea es una alteración relativamente infrecuente, de la que han sido descritos menos de 100 casos. Se comunica un caso de una enferma de 17 años de edad con clínica de dolor e inestabilidad en ambos hombros y hallazgo de displasia bilateral de cavidad glenoidea. Se realizó tratamiento conservador mediante pauta de refuerzo muscular con bandas elásticas de resistencia creciente con un resultado excelente calificado según puntuación de tabla de Rowe y cols. Desapareciendo la sensación de inestabilidad y habiendo cedido la clínica álgica.The glenoid hypoplasia is an uncommon condition. Less than 100 cases have been reported. We present the case of a 17 year old girl complaining of pain and instability in both shoulders and radiological findings of bilateral dysplasia of the glenoid. A non-operative treatment has been followed with an exercise program to strengthen the shoulder. This has been achieved with a progressive resistance rubber bands program. The final result has been excellent according to the appraisal table by Rowe et al., disappearing the instability sensation as well as the pain
Pre-freezing of multifractal exponents in Random Energy Models with logarithmically correlated potential
Boltzmann-Gibbs measures generated by logarithmically correlated random
potentials are multifractal. We investigate the abrupt change ("pre-freezing")
of multifractality exponents extracted from the averaged moments of the measure
- the so-called inverse participation ratios. The pre-freezing can be
identified with termination of the disorder-averaged multifractality spectrum.
Naive replica limit employed to study a one-dimensional variant of the model is
shown to break down at the pre-freezing point. Further insights are possible
when employing zero-dimensional and infinite-dimensional versions of the
problem. In particular, the latter version allows one to identify the pattern
of the replica symmetry breaking responsible for the pre-freezing phenomenon.Comment: This is published version, 11 pages, 1 figur
Statistical Mechanics of Logarithmic REM: Duality, Freezing and Extreme Value Statistics of Noises generated by Gaussian Free Fields
We compute the distribution of the partition functions for a class of
one-dimensional Random Energy Models (REM) with logarithmically correlated
random potential, above and at the glass transition temperature. The random
potential sequences represent various versions of the 1/f noise generated by
sampling the two-dimensional Gaussian Free Field (2dGFF) along various planar
curves. Our method extends the recent analysis of Fyodorov Bouchaud from the
circular case to an interval and is based on an analytical continuation of the
Selberg integral. In particular, we unveil a {\it duality relation} satisfied
by the suitable generating function of free energy cumulants in the
high-temperature phase. It reinforces the freezing scenario hypothesis for that
generating function, from which we derive the distribution of extrema for the
2dGFF on the interval. We provide numerical checks of the circular and
the interval case and discuss universality and various extensions. Relevance to
the distribution of length of a segment in Liouville quantum gravity is noted.Comment: 25 pages, 12 figures Published version. Misprint corrected,
references and note adde
Comparative pan-genome analysis of Piscirickettsia salmonis reveals genomic divergences within genogroups
Indexación: Scopus.Piscirickettsia salmonis is the etiological agent of salmonid rickettsial septicemia, a disease that seriously affects the salmonid industry. Despite efforts to genomically characterize P. salmonis, functional information on the life cycle, pathogenesis mechanisms, diagnosis, treatment, and control of this fish pathogen remain lacking. To address this knowledge gap, the present study conducted an in silico pan-genome analysis of 19 P. salmonis strains from distinct geographic locations and genogroups. Results revealed an expected open pan-genome of 3,463 genes and a core-genome of 1,732 genes. Two marked genogroups were identified, as confirmed by phylogenetic and phylogenomic relationships to the LF-89 and EM-90 reference strains, as well as by assessments of genomic structures. Different structural configurations were found for the six identified copies of the ribosomal operon in the P. salmonis genome, indicating translocation throughout the genetic material. Chromosomal divergences in genomic localization and quantity of genetic cassettes were also found for the Dot/Icm type IVB secretion system. To determine divergences between core-genomes, additional pan-genome descriptions were compiled for the so-termed LF and EM genogroups. Open pan-genomes composed of 2,924 and 2,778 genes and core-genomes composed of 2,170 and 2,228 genes were respectively found for the LF and EM genogroups. The core-genomes were functionally annotated using the Gene Ontology, KEGG, and Virulence Factor databases, revealing the presence of several shared groups of genes related to basic function of intracellular survival and bacterial pathogenesis. Additionally, the specific pan-genomes for the LF and EM genogroups were defined, resulting in the identification of 148 and 273 exclusive proteins, respectively. Notably, specific virulence factors linked to adherence, colonization, invasion factors, and endotoxins were established. The obtained data suggest that these genes could be directly associated with inter-genogroup differences in pathogenesis and host-pathogen interactions, information that could be useful in designing novel strategies for diagnosing and controlling P. salmonis infection. © 2017 Nourdin-Galindo, Sánchez, Molina, Espinoza-Rojas, Oliver, Ruiz, Vargas-Chacoff, Cárcamo, Figueroa, Mancilla, Maracaja-Coutinho and Yañez.https://www.frontiersin.org/articles/10.3389/fcimb.2017.00459/ful
Diverse routes to oscillation death in a coupled-oscillator system.
We study oscillation death (OD) in a well-known coupled-oscillator system that has been used to model cardiovascular phenomena. We derive exact analytic conditions that allow the prediction of OD through the two known bifurcation routes, in the same model, and for different numbers of coupled oscillators. Our exact analytic results enable us to generalize OD as a multiparameter-sensitive phenomenon. It can be induced, not only by changes in couplings, but also by changes in the oscillator frequencies or amplitudes. We observe synchronization transitions as a function of coupling and confirm the robustness of the phenomena in the presence of noise. Numerical and analogue simulations are in good agreement with the theory
SIGMA and XTE observations of the soft X-ray transient XTEJ1755-324
We present observations of the X-ray transient XTEJ1755-324 performed during
summer 1997 with the XTE satellite and with the SIGMA hard X-ray telescope
onboard the GRANAT observatory. The source was first detected in soft X-rays
with XTE on July 25 1997 with a rather soft X-ray spectrum and its outburst was
monitored in soft X-rays up to November 1997. On September 16 it was first
detected in hard X-rays by the French soft gamma ray telescope SIGMA during a
Galactic Center observation. The flux was stronger on September 16 and 17
reaching a level of about 110 mCrab in the 40-80 keV energy band. On the same
days the photon index of the spectrum was determined to be alpha =-2.3 +/- 0.9
(1 sigma error) while the 40-150 keV luminosity was about 8 x 10^{36} erg/s for
a distance of 8.5 kpc. SIGMA and XTE results on this source indicate that this
source had an ultrasoft-like state during its main outburst and a harder
secondary outburst in September. These characteristics make the source similar
to X-Nova Muscae 1991, a well known black hole candidate.Comment: 19 pages LaTeX, 6 Postscript figures included, Accepted by
Astrophysical Journa
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