140 research outputs found
Reactive models for biological regulatory networks
A reactive model, as studied by D. Gabbay and his collaborators,
can be regarded as a graph whose set of edges may be altered
whenever one of them is crossed. In this paper we show how reactive
models can describe biological regulatory networks and compare them
to Boolean networks and piecewise-linear models, which are some of the
most common kinds of models used nowadays. In particular, we show
that, with respect to the identification of steady states, reactive Boolean
networks lie between piecewise linear models and the usual, plain Boolean
networks. We also show this ability is preserved by a suitable notion of
bisimulation, and, therefore, by network minimisation.ERDF - The European Regional Development Fund through the Operational Programme for Competitiveness and Internationalisation - COMPETE 2020 Programme and by National Funds through the Portuguese funding agency, FCT - Fundação para a Ciência e a Tecnologia, within project POCI-01-0145-FEDER-030947. and project with reference UID/MAT/04106/2019 at CIDMA. D. Figueiredo also acknowledges the support given by FCT via the PhD scholarship PD/BD/114186/201
On the Right Path: A Modal Logic for Supervised Learning
Formal learning theory formalizes the process of inferring a general result
from examples, as in the case of inferring grammars from sentences when
learning a language. Although empirical evidence suggests that children can
learn a language without responding to the correction of linguistic mistakes,
the importance of Teacher in many other paradigms is significant. Instead of
focusing only on learner(s), this work develops a general framework---the
supervised learning game (SLG)---to investigate the interaction between Teacher
and Learner. In particular, our proposal highlights several interesting
features of the agents: on the one hand,Learner may make mistakes in the
learning process, and she may also ignore the potential relation between
different hypotheses; on the other hand, Teacher is able to correct Learner's
mistakes, eliminate potential mistakes and point out the facts ignored by
Learner. To reason about strategies in this game, we develop a modal logic of
supervised learning (SLL). Broadly, this work takes a small step towards
studying the interaction between graph games, logics and formal learning
theory.Comment: The paper was accepted by LORI 2019. But due to the page-limit
constraints, that Proceedings version does not include any proofs. In this
version, we show the proofs for the result
Effects of sleep on the academic performance of children with attention deficit and hyperactivity disorder
Attention deficit and hyperactivity disorder (ADHD) is commonly associated with disordered or disturbed sleep and the association of sleep problems with ADHD is complex and multidirectional. The purpose of this study was to analyze the relationship between sleep and academic performance, comparing children with ADHD and a control group without ADHD. Academic performance in Spanish, mathematics, and a foreign language (English) was evaluated. Different presentations of ADHD were considered as well as the potential difference between weekday and weekend sleep habits. The sample consisted of 75 children aged 6–12 in primary education. Accelerometry was used to study sleep, and school grades were used to gather information about academic performance. The results showed that ADHD influenced the amount of sleep during weekends, the time getting up at the weekends, weekday sleep efficiency, as well as academic performance. Given the effects that were seen in the variables linked to the weekend, it is necessary to consider a longitudinal design with which to determine if there is a cause and effect relationship
A note on reactive transitions and Reo connectors
The structure of a reactive transition system can to be modi
ed on the
y by e.g. removing, reversing or adding new transitions. The
topic has been studied by D. Gabbay and his collaborators in di erent
contexts. In this paper we take their work a step further, introducing a
suitable notion of bisimulation and obtaining a Hennessy-Milner theorem
with respect to a hybrid logic in which transition properties can be
expressed. Our motivation is to provide a characterisation of equivalence
for such systems in order to exploit their possible roles in the formal
description of software connectors in Reo, either from a behavioural (semantic)
or spatial (syntactic) point of view.“SmartEGOV/NORTE-01-0145-FEDER-000037”, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (EFDR). Additional support was provided by the European Regional Development Fund through the Operational Programme for Competitiveness and Internationalisation - COMPETE 2020 and by National Funds through the Portuguese funding agency, FCT - Fundação para a Ciência e a Tecnologia within project UID/MAT/04106/2013 at CIDMA. The first author is also supported by an Individual Doctoral Grant (reference number PD/BD/114186/2016
The Origin of Amerindians and the Peopling of the Americas According to HLA Genes: Admixture with Asian and Pacific People
The classical three-waves theory of American peopling through Beringia was based on a mixed anthropological and linguistic methodology. The use of mtDNA, Y chromosome and other DNA markers offers different results according to the different markers and methodologies chosen by different authors. At present, the peopling of Americas remains uncertain, regarding: time of population, number of peopling waves and place of peopling entrance among other related issues. In the present review, we have gathered most available HLA data already obtained about First Native American populations, which raise some doubts about the classical three waves of American peopling hypothesis. In summary, our conclusions are: 1) North West Canadian Athabaskans have had gene flow with: a) close neighboring populations, b) Amerindians, c) Pacific Islanders including East Australians and d) Siberians; 2) Beringia was probably not the only entrance of people to America: Pacific Ocean boat trips may have contributed to the HLA genetic American profile (or the opposite could also be true); 3) Amerindians entrance to America may have been different to that of Athabaskans and Eskimos and Amerindians may have been in their lands long before Athabaskans and Eskimos because they present and altogether different set of HLA-DRB1 allele frequencies; 4) Amerindians show very few “particular alleles”, almost all are shared with other Amerindians, Athabaskans and Pacific Islanders, including East Australians and Siberians; 5) Our results do not support the three waves model of American peopling, but another model where the people entrance is not only Beringia, but also Pacific Coast. Reverse migration (America to Asia) is not discarded and different movements of people in either direction in different times are supported by the Athabaskan population admixture with Asian-Pacific population and with Amerindians, 6) HLA variability is more common than allele veriability in Amerindians. Finally, it is shown that gene genealogy analises should be completed with allele frequency analyses in population relatednes and migrations studies
Completeness in hybrid type theory
We show that basic hybridization (adding nominals and @ operators) makes it possible to give straightforward Henkin-style completeness proofs even when the modal logic being hybridized is higher-order. The key ideas are to add nominals as expressions of type t, and to extend to arbitrary types the way we interpret @i in propositional and first-order hybrid logic. This means: interpret @iαa, where αa is an expression of any type a, as an expression of type a that rigidly returns the value that αa receives at the i-world. The axiomatization and completeness proofs are generalizations of those found in propositional and first-order hybrid logic, and (as is usual in hybrid logic) we automatically obtain a wide range of completeness results for stronger logics and languages. Our approach is deliberately low-tech. We don’t, for example, make use of Montague’s intensional type s, or Fitting-style intensional models; we build, as simply as we can, hybrid logic over Henkin’s logic.submittedVersionFil: Areces, Carlos Eduardo. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Blackburn, Patrick. University of Roskilde. Centre for Culture and Identity. Department of Philosophy and Science Studies; Dinamarca.Fil: Huertas, Antonia. Universitat Oberta de Catalunya; España.Fil: Manzano, María. Universidad de Salamanca; España.Ciencias de la Computació
Elevation of Cardiac Troponins After Endurance Running Competitions
In the present investigation, we selected 63 healthy runners (in triplets) from a group of 322 nonprofessional finishers because of their similarities in age (mean±SD age, 37±7 years), anthropometry (66.9±12.8 kg), and running experience (3.3±0.2 years). The triplets also had similar 10-year absolute cardiovascular risks (2.8±2.1%) calculated by the non–laboratory-based Framingham function.5 In each group, there were 13 women and 8 men. From each triplet, 1 runner competed in a 10-km race, another in a half-marathon race, and the third in a full marathon race. As would be expected, as a result of the different training patterns for each distance, training volume in the month before the race increased with the competition distance (23.9±9.0, 34.8±8.0, and 40.6±16.4 km/wk for 10-km runners, half-marathoners, and marathoners, respectively; P<0.01). Before and 10 minutes after the race, body mass was measured to assess dehydration. Blood samples were obtained to measure cardiac biomarkers, including high-sensitivity cardiac troponins I and T, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and the cardiac (creatine kinase-MB) and skeletal muscle (creatine kinase-MM) isoenzymes of creatine kinase and myoglobin at the end of the races. The between-group differences in these variables were analyzed by a 2-way ANOVA. The study was approved by the Ethics Committee for Research of the Camilo Jose Cela University. All the research protocols described here were carried out in accordance with the Declaration of Helsinki, and all subjects gave informed consent to participate in the study
Asymmetric Combination of Logics is Functorial: A Survey
Asymmetric combination of logics is a formal process that develops the characteristic features of a specific logic on top of another one. Typical examples include the development of temporal, hybrid, and probabilistic dimensions over a given base logic. These examples are surveyed in the paper under a particular perspective—that this sort of combination of logics possesses a functorial nature. Such a view gives rise to several interesting questions. They range from the problem of combining translations (between logics), to that of ensuring property preservation along the process, and the way different asymmetric combinations can be related through appropriate natural transformations
The use of compression stockings during a marathon competition to reduce exercise-induced muscle damage: are they really useful?
OBJECTIVES:
To examine the efficacy of wearing compression stockings to prevent muscle damage and to maintain running performance during a marathon competition.
BACKGROUND:
Exercise-induced muscle damage has been identified as one of the main causes of the progressive decrease in running and muscular performance found during marathon races.
METHODS:
Thirty-four experienced runners were pair-matched for age, anthropometric data, and best race time in the marathon, and randomly assigned to a control group (n = 17) of runners who wore conventional socks or to a group of runners who wore foot-to-knee graduated compression stockings (n = 17). Before and after the race, a sample of venous blood was obtained, and jump height and leg muscle power were measured during a countermovement jump. Serum myoglobin and creatine kinase concentrations were determined as blood markers of muscle fiber damage
Efectos de una maratón en valores hematológicos
Introducción: La maratón lleva asociado un estrés fi siológico en el organismo, si bien existe carencia de información sobre cómo afecta a los parámetros sanguíneos en corredores populares y si existe relación con variables de rendimiento, entrenamiento y experiencia deportiva.
Propósito: Evaluar los cambios producidos en variables hematológicas en corredores populares tras participar en una maratón en ambiente caluroso. Un segundo objetivo fue analizar la relación entre la experiencia deportiva, el nivel de entrenamiento y el tiempo de carrera con los cambios hematológicos.
Métodos: Se extrajo sangre venosa a 41 maratonianos, 35 hombres y 6 mujeres, antes y después de una maratón. Su edad fue de 41,15+8,1 años, y entrenaban como media 55,917,12 kilómetros semanales. El tiempo en meta fue de 3:40:410:32:02.
Las muestras fueron medidas con analizadores bioquímicos estándar para determinar los valores de la serie roja y serie blanca
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