10,140 research outputs found
Entropy production and Kullback-Leibler divergence between stationary trajectories of discrete systems
The irreversibility of a stationary time series can be quantified using the
Kullback-Leibler divergence (KLD) between the probability to observe the series
and the probability to observe the time-reversed series. Moreover, this KLD is
a tool to estimate entropy production from stationary trajectories since it
gives a lower bound to the entropy production of the physical process
generating the series. In this paper we introduce analytical and numerical
techniques to estimate the KLD between time series generated by several
stochastic dynamics with a finite number of states. We examine the accuracy of
our estimators for a specific example, a discrete flashing ratchet, and
investigate how close is the KLD to the entropy production depending on the
number of degrees of freedom of the system that are sampled in the
trajectories.Comment: 14 pages, 7 figure
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Cognitive impact of neuronal antibodies: encephalitis and beyond
Abstract: Cognitive dysfunction is a common feature of autoimmune encephalitis. Pathogenic neuronal surface antibodies are thought to mediate distinct profiles of cognitive impairment in both the acute and chronic phases of encephalitis. In this review, we describe the cognitive impairment associated with each antibody-mediated syndrome and, using evidence from imaging and animal studies, examine how the nature of the impairment relates to the underlying neuroimmunological and receptor-based mechanisms. Neuronal surface antibodies, particularly serum NMDA receptor antibodies, are also found outside of encephalitis although the clinical significance of this has yet to be fully determined. We discuss evidence highlighting their prevalence, and association with cognitive outcomes, in a number of common disorders including cancer and schizophrenia. We consider mechanisms, including blood-brain barrier dysfunction, which could determine the impact of these antibodies outside encephalitis and account for much of the clinical heterogeneity observed
High-precision muon decay predictions for ALP searches
We present an improved theoretical prediction of the positron energy spectrum
for the polarised Michel decay . In addition
to the full next-to-next-to-leading order correction of order in the
electromagnetic coupling, we include logarithmically enhanced terms at even
higher orders. Logarithms due to collinear emission are included at
next-to-leading accuracy up to order . At the endpoint of the Michel
spectrum, soft photon emission results in large logarithms that are resummed up
to next-to-next-to-leading logarithmic accuracy. We apply our results in the
context of the MEG II and Mu3e experiments to estimate the impact of the theory
error on the branching ratio sensitivity for the lepton-flavour-violating decay
of a muon into an axion-like particle .Comment: 36 pages, 14 figure
Sistema de gestão territorial da faixa de fronteira para a defesa agropecuária.
This article presents a technical note about the initiatives developed by Embrapa Satellite Monitoring and the Office of the Secretary of Agricultural Defense - SDA of the Agriculture, Livestock farming and Supplying - MAPA. Those actions are going to structure a system of territorial management of Brazilian borderlands aimaing to support efforts toward the prevention, monitoring and control of the incidence of sanitary risks
Robinow Syndrome and otorhinolaryngoly - A case report
A Síndrome de Robinow é uma doença genética rara, com menos de 200 casos registados no mundo. Caracteriza-se pelo encurtamento mesomélico dos membros, baixa estatura, hipoplasia genital externa e uma fácies fetal. A sua transmissão pode ser autossómica recessiva ou dominante. Este artigo descreve o caso clínico de uma criança com diagnóstico pós-natal de Síndrome de Robinow esporádica autossómica dominante. Aos 12 anos de idade as anomalias otorrinolaringológicas incluíam a presença de uma bossa frontal, nariz curto com dorso largo, hipoplasia da maxila, fenda palatina corrigida e hipoacusia de condução bilateral. A Síndrome de Robinow é uma condição geneticamente heterogénea que pode ser facilmente diagnosticada na infância ou mesmo na avaliação pré-natal. O acompanhamento e intervenção otorrinolaringológicos podem melhorar o desenvolvimento e a qualidade de vida destas crianças.info:eu-repo/semantics/publishedVersio
Anharmonic transitions in nearly dry L-cysteine I
Two special dynamical transitions of universal character have been recently
observed in macromolecules at K and K.
Despite their relevance, a complete understanding of the nature of these
transitions and their consequences for the bio-activity of the macromolecule is
still lacking. Our results and analysis concerning the temperature dependence
of structural, vibrational and thermodynamical properties of the orthorhombic
polymorph of the amino acid L-cysteine (at a hydration level of 3.5%) indicated
that the two referred temperatures define the triggering of very simple and
specific events that govern all the biochemical interactions of the
biomolecule: activation of rigid rotors (), phonon-phonon interactions
with phonons of water dimer (), and water rotational barriers
surpassing ().Comment: 4 pages, 4 figures, submitted to Physical Review Letter
Immunization and Aging: a Learning Process in the Immune Network
The immune system can be thought as a complex network of different
interacting elements. A cellular automaton, defined in shape-space, was
recently shown to exhibit self-regulation and complex behavior and is,
therefore, a good candidate to model the immune system. Using this model to
simulate a real immune system we find good agreement with recent experiments on
mice. The model exhibits the experimentally observed refractory behavior of the
immune system under multiple antigen presentations as well as loss of its
plasticity caused by aging.Comment: 4 latex pages, 3 postscript figures attached. To be published in
Physical Review Letters (Tentatively scheduled for 5th Oct. issue
Experimental Adhesion Prevention Studies: A Comparative Study in a Rabbit Model
Background: Adhesions formation after abdominal surgery is a problem that causes many complications in the patient’s future life. In this study we compare the possible individual effects of Ringer ́s lactate, Adept® and Mesofol® and the combined effects of Adept® and Mesofol® in the prevention of post surgical adhesions formation in a standardised rabbit model.Materials and Methods: 90 rabbits were divided into 9 groups. The same experimental method was used in all rabbits to produce adhesions, consisting of cecal and sigmoid abrasion and excision of parietal peritoneum. The rabbits were operated after 2 weeks to assess the adhesions occurring. The results were analysed using the chi-square test and the Fisher exact test when needed.Results: Comparison of adhesion stages demonstrated a significant difference between the control group and the Adept® groups (p<0.05) in both branches. The adhesion grade of the combined treatment groups (G5 and G9) was not statistically significant (p>0.05). In the Mesofol® group and the combined group, four and two rabbits, respectively, developed granulomas. Conclusions: Adept® used individually reduced the adhesion grade. The Adept® and Mesofol® combination was less effective in reducing adhesion formation in comparison to the Adept® group by itself. On the other hand, in our experimental study, the usage of Mesofol®, alone or in combination, caused foreign body granulomas in 6 animals. Although the literature is very sufficient in comparison several materials for decreasing adhesion formation, we believe that our study provides more valuable evidence in this area. Due to the appearance of six cases of foreign body granulomas, detailed studies focused on this matter are needed in the future. Keywords: Post-operative adhesions; comparative study; prevention; rabbit model. Introdução: A formação de aderências após a cirurgia abdominal é um problema que causa muitas complicações na vida futura do doente. Neste estudo, comparamos os possíveis efeitos individuais do Ringer lactato, Adept® e do Mesofol®, e os efeitos combinados do Adept® e do Mesofol® na prevenção da formação de aderências pós-cirúrgicas num modelo padronizado de coelhos.Materiais e Métodos: 90 coelhos foram divididos em nove grupos. O mesmo método experimental foi utilizado em todos os coelhos para favorecer a produção de aderências, realizando abrasão do cego e da sigmoideia e excisão do peritoneu parietal. Os coelhos foram operados após duas semanas para avaliar a ocorrência de aderências. Os resultados foram analisados por meio do teste do qui-quadrado e do teste exacto de Fisher, quando necessário.Resultados: A comparação em estadios de aderência demonstrou uma diferença significativa entre o grupo controlo e os grupos Adept® (p <0,05) em ambos os ramos. O grau de aderências dos grupos de tratamento combinado (G5 e G9) não foi estatisticamente significativo (p <0,05). No grupo do Mesofol® e no grupo combinado, quatro e dois coelhos, respectivamente, desenvolveram granulomas. Conclusões: Adept® utilizado individualmente reduziu o grau de aderências. O Adept® combinado com o Mesofol® foi menos eficaz na redução da formação de aderências em comparação com o grupo do Adept®, por si só. Por outro lado, o uso de Mesofol® isoladamente ou em conjunto podem aumentar o risco de granulomas. Estudos mais detalhados são necessários, e futuros estudos sobre a eficácia de um material para diminuir a formação de aderências deve incluir uma comparação de controle de diversos materiais num mesmo modelo.Palavras-Chave: aderências pós-operatórias; estudo comparativo; prevenção; modelo animal em coelhos
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