Network centrality: an introduction

Centrality is a key property of complex networks that influences the behavior of dynamical processes, like synchronization and epidemic spreading, and can bring important information about the organization of complex systems, like our brain and society. There are many metrics to quantify the node centrality in networks. Here, we review the main centrality measures and discuss their main features and limitations. The influence of network centrality on epidemic spreading and synchronization is also pointed out in this chapter. Moreover, we present the application of centrality measures to understand the function of complex systems, including biological and cortical networks. Finally, we discuss some perspectives and challenges to generalize centrality measures for multilayer and temporal networks.Comment: Book Chapter in "From nonlinear dynamics to complex systems: A Mathematical modeling approach" by Springe

Can the evolution of music be analyzed in a quantitative manner?

We propose a methodology to study music development by applying multivariate statistics on composers characteristics. Seven representative composers were considered in terms of eight main musical features. Grades were assigned to each characteristic and their correlations were analyzed. A bootstrap method was applied to simulate hundreds of artificial composers influenced by the seven representatives chosen. Afterwards we quantify non-numeric relations like dialectics, opposition and innovation. Composers differences on style and technique were represented as geometrical distances in the feature space, making it possible to quantify, for example, how much Bach and Stockhausen differ from other composers or how much Beethoven influenced Brahms. In addition, we compared the results with a prior investigation on philosophy. Opposition, strong on philosophy, was not remarkable on music. Supporting an observation already considered by music theorists, strong influences were identified between composers by the quantification of dialectics, implying inheritance and suggesting a stronger master-disciple evolution when compared to the philosophy analysis.Comment: 8 pages, 6 figures, added references for sections 1 and 4.C, better mathematical description on section 2. New values and interpretation, now considering a bootstrap metho

Community Structure Characterization

This entry discusses the problem of describing some communities identified in a complex network of interest, in a way allowing to interpret them. We suppose the community structure has already been detected through one of the many methods proposed in the literature. The question is then to know how to extract valuable information from this first result, in order to allow human interpretation. This requires subsequent processing, which we describe in the rest of this entry

Echinacea purpurea fractions represent promising plant-based anti-inflammatory formulations

Echinacea purpurea is traditionally used in the treatment of inflammatory diseases. Therefore, we investigated the anti-inflammatory capacity of E. purpurea dichloromethanolic (DE) and ethanolic extracts obtained from flowers and roots (R). To identify the class of compounds responsible for the strongest bioactivity, the extracts were fractionated into phenol/carboxylic acid (F1) and alkylamide fraction (F2). The chemical fingerprint of bioactive compounds in the fractions was evaluated by LC-HRMS. E. purpurea extracts and fractions significantly reduced pro-inflammatory cytokines (interleukin 6 and/or tumor necrosis factor) and reactive oxygen and nitrogen species (ROS/RNS) production by lipopolysaccharide-stimulated primary human monocyte-derived macrophages. Dichloromethanolic extract obtained from roots (DE-R) demonstrated the strongest anti-inflammatory activity. Moreover, fractions exhibited greater anti-inflammatory activity than whole extract. Indeed, alkylamides must be the main compounds responsible for the anti-inflammatory activity of extracts; thus, the fractions presenting high content of these compounds presented greater bioactivity. It was demonstrated that alkylamides exert their anti-inflammatory activity through the downregulation of the phosphorylation of p38, ERK 1/2, STAT 3, and/or NF-κB signaling pathways, and/or downregulation of cyclooxygenase 2 expression. E. purpurea extracts and fractions, mainly DE-R-F2, are promising and powerful plant-based anti-inflammatory formulations that can be further used as a basis for the treatment of inflammatory diseases.This work was financially supported by the FCT to the Ph.D. grants of S.F.V. (PD/BD/135246/2017 and COVID/BD/152012/2021), S.M.G. (SFRH/BD/136814/2018), and C.C. (CEECIND/04058/2018), and the projects PATH (PD/00169/2013), HEALTH-UNORTE (NORTE-01- 0145-FEDER-000039) and the NORTE 2020 Structured Project, co-funded by Norte2020 (NORTE-01- 0145-FEDER-000021

Optimizing mate selection: a genetic algorithm approach.

Background: Genetic Improvement Programs (GIP) aim to enhance productionefficiency of beef cattle. The main way to guide this enhancement is by choosing thebest mates among sires and cows, in order to maximize the offspring GeneticQualification Index (QGI), which is measured by an index defined by the GIP andcomputed for each animal of the herd. This paper describes a genetic algorithm, whichcan recommend an optimal set of matings among sires and cows, in order to maximizethe QGI of the herd. Breeders can define constraints regarding level of problems,which must be avoided, and they also can alter the traits relative importance consideredin QGI, according their particular interests. This algorithm was applied to a herd of aBrazilian breeder, which participates of a GIP, and it found optimal matings in order toincrease QGI value. We have simulated different scenarios considering variations onfitness functions, which combine QGI and level of problems, in order to find the optimalmatings. Proposed approach was successfully used to recommend optimal matingdecisions by Brazilian Hereford and Braford cattle breeders Association leading to animprovement of offspring QGI.Keywords: Genetic Improvement, Beef Cattle, Artificial Intelligence, EvolutionaryComputing.Editors: J. Kucera, P. Bucek, D. Lipovsky, X. Bourrigan and M. Burke

Prasinezumab slows motor progression in rapidly progressing early-stage Parkinson\u27s disease

\ua9 The Author(s) 2024. Prasinezumab, a monoclonal antibody that binds aggregated α-synuclein, is being investigated as a potential disease-modifying therapy in early-stage Parkinson’s disease. Although in the PASADENA phase 2 study, the primary endpoint (Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) sum of Parts I + II + III) was not met, prasinezumab-treated individuals exhibited slower progression of motor signs than placebo-treated participants (MDS-UPDRS Part III). We report here an exploratory analysis assessing whether prasinezumab showed greater benefits on motor signs progression in prespecified subgroups with faster motor progression. Prasinezumab’s potential effects on disease progression were assessed in four prespecified and six exploratory subpopulations of PASADENA: use of monoamine oxidase B inhibitors at baseline (yes versus no); Hoehn and Yahr stage (2 versus 1); rapid eye movement sleep behavior disorder (yes versus no); data-driven subphenotypes (diffuse malignant versus nondiffuse malignant); age at baseline (≥60 years versus <60 years); sex (male versus female); disease duration (>12 months versus <12 months); age at diagnosis (≥60 years versus <60 years); motor subphenotypes (akinetic–rigid versus tremor-dominant); and motor subphenotypes (postural instability gait dysfunction versus tremor-dominant). In these subpopulations, the effect of prasinezumab on slowing motor signs progression (MDS-UPDRS Part III) was greater in the rapidly progressing subpopulations (for example, participants who were diffuse malignant or taking monoamine oxidase B inhibitors at baseline). This exploratory analysis suggests that, in a trial of 1-year duration, prasinezumab might reduce motor progression to a greater extent in individuals with more rapidly progressing Parkinson’s disease. However, because this was a post hoc analysis, additional randomized clinical trials are needed to validate these findings