Structural Operational Semantics for Stochastic Process Calculi

A syntactic framework called SGSOS, for defining well-behaved Markovian stochastic transition systems, is introduced by analogy to the GSOS congruence format for nondeterministic processes. Stochastic bisimilarity is guaranteed a congruence for systems defined by SGSOS rules. Associativity of parallel composition in stochastic process algebras is also studied within the SGSOS framework

RPO, Second-order Contexts, and Lambda-calculus

First, we extend Leifer-Milner RPO theory, by giving general conditions to obtain IPO labelled transition systems (and bisimilarities) with a reduced set of transitions, and possibly finitely branching. Moreover, we study the weak variant of Leifer-Milner theory, by giving general conditions under which the weak bisimilarity is a congruence. Then, we apply such extended RPO technique to the lambda-calculus, endowed with lazy and call by value reduction strategies. We show that, contrary to process calculi, one can deal directly with the lambda-calculus syntax and apply Leifer-Milner technique to a category of contexts, provided that we work in the framework of weak bisimilarities. However, even in the case of the transition system with minimal contexts, the resulting bisimilarity is infinitely branching, due to the fact that, in standard context categories, parametric rules such as the beta-rule can be represented only by infinitely many ground rules. To overcome this problem, we introduce the general notion of second-order context category. We show that, by carrying out the RPO construction in this setting, the lazy observational equivalence can be captured as a weak bisimilarity equivalence on a finitely branching transition system. This result is achieved by considering an encoding of lambda-calculus in Combinatory Logic.Comment: 35 pages, published in Logical Methods in Computer Scienc

A moderate 500-m treadmill walk for estimating peak oxygen uptake in men with NYHA class I-II heart failure and reduced left ventricular ejection fraction

Background: Maximal cardiopulmonary exercise testing (CPX) is the gold-standard for cardiorespiratory fitness assessment in chronic heart failure (CHF) patients. However, high costs, required medical supervision, and safety concerns make maximal exercise testing impractical for evaluating mobility-impaired adults. Thus, several submaximal walking protocols have been developed and currently used to estimate peak oxygen consumption (VO(2)peak)in CHF patients. However, these tests have to be performed at close to maximum exercise intensity. The aim of this study was to examine the validity of a 500-m treadmill-walking test carried out at moderate intensity for estimating VO(2)peak in community-dwelling adult and elderly patients with CHF and reduced left ventricular ejection fraction (HFrEF).Methods: Forty-three clinically stable men with HFrEF (age 67.7 +/- 9.2 years, and left ventricular ejection fraction, LVEF 38% +/- 6%) underwent exercise testing during an outpatient cardiac rehabilitation/secondary prevention program. Each patients completed a CPX, and a moderate and self-paced (11-13/20 on the Borg scale) 500-m treadmill-walking test. Age, weight, height, walk time, and heart rate during the 500-m test were entered into prediction equations previously validated for VO(2)peak estimation from a 1000-m walking test in patients with cardiovascular disease and preserved LVEF.Results: Directly measured and estimated VO(2)peak values were not different (21.6 +/- 4.9 vs 21.7 +/- 4.6 mL/kg/min). The comparison between measured and estimated VO(2)peak values yielded a correlation of R = 0.97 (SEE = 0.7 mL/kg/min, P < 0.0001). The slope and the intercept coincided with the line of identity (Passing and Bablock analysis, P = 0.50). Residuals were normally distributed, and the examination of the Bland-Altman analysis do not show systematic or proportional error.Conclusions: A moderate and self-regulated 500-m treadmill-walking test is a valid tool for VO(2)peak estimation in patients with HFrEF. These findings may have practical implications in the context of transitioning from clinically based programs to fitness facilities or self-guided exercise programs in adults and elderly men with HFrEF

Cell-specific occupancy of an extended repertoire of CREM and CREB binding loci in male germ cells

Background: CREB and CREM are closely related factors that regulate transcription in response to various stress, metabolic and developmental signals. The CREMτ activator isoform is selectively expressed in haploid spermatids and plays an essential role in murine spermiogenesis.Results: We have used chromatin immunoprecipitation coupled to sequencing (ChIP-seq) to map CREM and CREB target loci in round spermatids from adult mouse testis and spermatogonia derived GC1-spg cells respectively. We identify more than 9000 genomic loci most of which are cell-specifically occupied. Despite the fact that round spermatids correspond to a highly specialised differentiated state, our results show that they have a remarkably accessible chromatin environment as CREM occupies more than 6700 target loci corresponding not only to the promoters of genes selectively expressed in spermiogenesis, but also of genes involved in functions specific to other cell types. The expression of only a small subset of these target genes are affected in the round spermatids of CREM knockout animals. We also identify a set of intergenic binding loci some of which are associated with H3K4 trimethylation and elongating RNA polymerase II suggesting the existence of novel CREB and CREM regulated transcripts.Conclusions: We demonstrate that CREM and CREB occupy a large number of promoters in highly cell specific manner. This is the first study of CREM target promoters directly in a physiologically relevant tissue in vivo and represents the most comprehensive experimental analysis of CREB/CREM regulatory potential to date

The future of Cybersecurity in Italy: Strategic focus area

This volume has been created as a continuation of the previous one, with the aim of outlining a set of focus areas and actions that the Italian Nation research community considers essential. The book touches many aspects of cyber security, ranging from the definition of the infrastructure and controls needed to organize cyberdefence to the actions and technologies to be developed to be better protected, from the identification of the main technologies to be defended to the proposal of a set of horizontal actions for training, awareness raising, and risk management

Structured Operational Semantics for Graph Rewriting

Process calculi and graph transformation systems provide models of reactive systems with labelled transition semantics. While the semantics for process calculi is compositional, this is not the case for graph transformation systems, in general. Hence, the goal of this article is to obtain a compositional semantics for graph transformation system in analogy to the structural operational semantics (SOS) for Milner's Calculus of Communicating Systems (CCS). The paper introduces an SOS style axiomatization of the standard labelled transition semantics for graph transformation systems. The first result is its equivalence with the so-called Borrowed Context technique. Unfortunately, the axiomatization is not compositional in the expected manner as no rule captures "internal" communication of sub-systems. The main result states that such a rule is derivable if the given graph transformation system enjoys a certain property, which we call "complementarity of actions". Archetypal examples of such systems are interaction nets. We also discuss problems that arise if "complementarity of actions" is violated.Comment: In Proceedings ICE 2011, arXiv:1108.014

Brain-muscle communication prevents muscle aging by maintaining daily physiology

Muñoz-Cánoves, Pur

Acordando de um sono de cem anos: uma nova espécie de Nothoscordum (Amaryllidaceae, Allioideae) da Floresta Atlântica brasileira

Introdução e objetivos: A Serra do Itapetinga abriga um dos mais importantes remanescentes de Floresta Atlântica da Macrometrópole Paulista, a região mais populosa do Brasil. No contexto do tratamento monográfico de Nothoscordum para o país, uma nova espécie com distribuição atual restrita à Serra do Itapetinga foi identificada, e é aqui descrita e ilustrada. M&M: O reconhecimento da nova espécie está baseado tanto em dados morfológicos como moleculares e citogenéticos. As descrições e comparações morfológicas foram feitas a partir da análise de materiais vivos ou depositados nas coleções dos herbários consultados. Com base em marcadores nuclear (ITS) e plastidiais (ndhF e matK) uma filogenia molecular incluindo a espécie descrita é apresentada. O seu estado de conservação foi avaliado de acordo com diretrizes e critérios da IUCN. Resultados: Nothoscordum itapetinga apresenta filamentos estaminais não fundidos na base, uma característica típica da seção Nothoscordum. Seu posicionamento nesta seção também é suportado por dados moleculares e o número cromossômico básico. São fornecidos seu número cromossômico, fórmula cariotípica e conteúdo total de DNA. Comentários sobre sua distribuição, hábitat e conservação são apresentados. Conclusões: Com base nos dados disponíveis, a nova espécie é considerada Criticamente em Perigo de extinção. As localidades de ocorrência sofreram por décadas com os impactos decorrentes do uso intensivo e não ordenado, além de incêndios florestais, e que alteraram parte de sua estrutura e composição florística. Somados aos esforços para a localização de registros adicionais, ações urgentes de proteção e conservação são consideradas fundamentais para garantir a sobrevivência dos acessos remanescentes de N. itapetinga

Light Induction of a Vertebrate Clock Gene Involves Signaling through Blue-Light Receptors and MAP Kinases

AbstractThe signaling pathways that couple light photoreception to entrainment of the circadian clock have yet to be deciphered. Two prominent groups of candidates for the circadian photoreceptors are opsins (e.g., melanopsin) and blue-light photoreceptors (e.g., cryptochromes). We have previously showed that the zebrafish is an ideal model organism in which to study circadian regulation and light response in peripheral tissues. Here, we used the light-responsive zebrafish cell line Z3 to dissect the response of the clock gene zPer2 to light. We show that the MAPK (mitogen-activated protein kinase) pathway is essential for this response, although other signaling pathways may also play a role. Moreover, action spectrum analyses of zPer2 transcriptional response to monochromatic light demonstrate the involvement of a blue-light photoreceptor. The Cry1b and Cry3 cryptochromes constitute attractive candidates as photoreceptors in this setting. Our results establish a link between blue-light photoreceptors, probably cryptochromes, and the MAPK pathway to elicit light-induced transcriptional activation of clock genes