Double transition in kinetic exchange opinion models with activation dynamics.

In this work, we study a model of opinion dynamics considering activation/deactivation of agents. In other words, individuals are not static and can become inactive and drop out from the discussion. A probability [Formula: see text] governs the deactivation dynamics, whereas social interactions are ruled by kinetic exchanges, considering competitive positive/negative interactions. Inactive agents can become active due to interactions with active agents. Our analytical and numerical results show the existence of two distinct non-equilibrium phase transitions, with the occurrence of three phases, namely ordered (ferromagnetic-like), disordered (paramagnetic-like) and absorbing phases. The absorbing phase represents a collective state where all agents are inactive, i.e. they do not participate in the dynamics, inducing a frozen state. We determine the critical value [Formula: see text] above which the system is in the absorbing phase independently of the other parameters. We also verify a distinct critical behaviour for the transitions among different phases. This article is part of the theme issue 'Kinetic exchange models of societies and economies'.

Sensor Fusion and Smart Sensor in Sports and Biomedical Applications.

The following work presents an overview of smart sensors and sensor fusion targeted at biomedical applications and sports areas. In this work, the integration of these areas is demonstrated, promoting a reflection about techniques and applications to collect, quantify and qualify some physical variables associated with the human body. These techniques are presented in various biomedical and sports applications, which cover areas related to diagnostics, rehabilitation, physical monitoring, and the development of performance in athletes, among others. Although some applications are described in only one of two fields of study (biomedicine and sports), it is very likely that the same application fits in both, with small peculiarities or adaptations. To illustrate the contemporaneity of applications, an analysis of specialized papers published in the last six years has been made. In this context, the main characteristic of this review is to present the largest quantity of relevant examples of sensor fusion and smart sensors focusing on their utilization and proposals, without deeply addressing one specific system or technique, to the detriment of the others.

Modeling the functional network of primary intercellular Ca2+ wave propagation in astrocytes and its application to study drug effects.

We introduce a simple procedure of multivariate signal analysis to uncover the functional connectivity among cells composing a living tissue and describe how to apply it for extracting insight on the effect of drugs in the tissue. The procedure is based on the covariance matrix of time resolved activity signals. By determining the time-lag that maximizes covariance, one derives the weight of the corresponding connection between cells. Introducing simple constraints, it is possible to conclude whether pairs of cells are functionally connected and in which direction. After testing the method against synthetic data we apply it to study intercellular propagation of Ca(2+) waves in astrocytes following an external stimulus, with the aim of uncovering the functional cellular connectivity network. Our method proves to be particularly suited for this type of networking signal propagation where signals are pulse-like and have short time-delays, and is shown to be superior to standard methods, namely a multivariate Granger algorithm. Finally, based on the statistical analysis of the connection weight distribution, we propose simple measures for assessing the impact of drugs on the functional connectivity between cells.

Evaluating the roughness dynamics of kefir biofilms grown on Amazon cupuaçu juice: a monofractal and multifractal approach.

We conducted a comprehensive analysis of the surface microtexture of kefir biofilms grown on Theobroma grandiflorum Shum (cupuaçu) juice using atomic force microscopy. Our goal was to investigate the unique monofractal and multifractal spatial patterns of these biofilms to complement the existing limited literature. The biofilms were prepared dispersing four different concentrations of kefir grains in cupuaçu juice. Our morphological analysis showed that the surface of the obtained biofilms is essentially formed by the presence of cupuaçu fibers and microorganisms like lactobacilli and yeast. The topographic height-based parameter analysis reveals that there is a dependence between surface roughness and the concentration of kefir grains used. The strongly anisotropic well-centralized topographical height distribution of the biofilms also exhibited a quasi-symmetrical and platykurtic pattern. The biofilms exhibit comparable levels of spatial complexity, surface percolation and surface homogeneity, which can be attributed to their similar topographic uniformity. This aspect was further supported by the presence of similar multifractality in the biofilms, suggesting that despite their varying topographic roughness, their vertical growth dynamics follow a similar pattern. Our findings demonstrate that the surface roughness of kefir biofilms cultivated on cupuaçu juice is influenced by the concentration of kefir grains in the precursor solution. However, this dependence follows a consistent pattern across different concentrations. Graphical Abstract.

Genetic determinants and absence of breast cancer in Xavante Indians in Sangradouro Reserve, Brazil.

Genetic compositions of distinct human populations are different. How genomic variants influence many common and rare genetic diseases is always of great medical and anthropological interest, and understanding of genetic architectures of population groups in relation to diseases can advance our knowledge of medicine. Here, we have studied the genomic architecture of a group of Xavante Indians, an indigenous population in Brazil, and compared them with normal populations from the 1000 Genomes Projects. Principal component analysis (PCA) indicates that the Xavante Indians are genetically distinctive when compared to other ethnic groups. No incidence of breast cancer cases has ever been reported in the population, and polygenic risk analysis indicates extremely low breast cancer risk in this population when compared with germline TCGA (The Cancer Genome Atlas) breast cancer normal control samples. Low germinal mutation burden among this population is also observed. Our findings will help to deepen the understanding of breast cancer and might also provide new approaches to study the disease.

Morphological and multifractal properties of Cr thin films deposited onto different substrates.

In this study, the morphological properties and micro-roughness of chromium thin film prepared by thermal evaporation technique and confirmed via EDS analysis are examined on different substrates of BK7, Silicon (Si), and glass using atomic force microscope analysis (AFM). Analysis of amplitude parameters, Minkowski functionals, and films' spatial microtexture extracted from AFM analysis showed the difference between glass substrate and the other two (BK7 and Si) substrates for the growth of chromium thin films. In addition, we observed robust signatures of multifractality of the Cr thin films deposited on all substrates we studied. Moreover, we highlight that the Glass substrates displayed the strongest multifractality indicating that such samples present space filling properties distributed over more spatial scales than the samples of BK7 and Si.

Molecular detection of blood meal source up to three months since the last meal: Experimental starvation resistance in triatomines.

The identification of Blood Meal Source (BMS) in hematophagous vectors contributes to a better understanding of the ecology of hemoparasite transmission. Those insects can endure long periods without feeding, waiting for a favorable setting. Although this represents an important behavior observed in those groups, such as triatomines, little is known about how time can affect BMS detection, especially considering extended periods. To comprehend to which extent this behavioral phenomenon can impact molecular detection, we submitted two groups of Rhodnius robustus to increasing periods of starvation under experimental conditions. It was possible to recover the BMS until the 12th week of the starvation process. Nymphs were more resistant to prolonged periods of starvation (up to more than 189 days) than adults (maximum of 137 days), with no significant difference between their weights after being fed. The study brought new insights to the understanding of Trypanosoma cruzi transmission by R. robustus in the nature, with a temporal perspective.

Effect of the Deposition Time on the Structural, 3D Vertical Growth, and Electrical Conductivity Properties of Electrodeposited Anatase-Rutile Nanostructured Thin Films.

TiO2 time-dependent electrodeposited thin films were synthesized using an electrophoretic apparatus. The XRD analysis revealed that the films could exhibit a crystalline structure composed of ~81% anatase and ~6% rutile after 10 s of deposition, with crystallite size of 15 nm. AFM 3D maps showed that the surfaces obtained between 2 and 10 s of deposition exhibit strong topographical irregularities with long-range and short-range correlations being observed in different surface regions, a trend also observed by the Minkowski functionals. The height-based ISO, as well as specific surface microtexture parameters, showed an overall decrease from 2 to 10 s of deposition, showing a subtle decrease in the vertical growth of the films. The surfaces were also mapped to have low spatial dominant frequencies, which is associated with the similar roughness profile of the films, despite the overall difference in vertical growth observed. The electrical conductivity measurements showed that despite the decrease in topographical roughness, the films acquired a thickness capable of making them increasingly insulating from 2 to 10 s of deposition. Thus, our results prove that the deposition time used during the electrophoretic experiment consistently affects the films' structure, morphology, and electrical conductivity.

Molecular phylogenetic relationships and the coevolution of placentotrophy and superfetation in Poecilia (Poeciliidae: Cyprinodontiformes).

Members of Poeciliidae are used as model organisms for experimental studies on natural and sexual selection, and comparative studies of life-history evolution. The latter have demonstrated multiple origins of both superfetation and placentotrophy within Poeciliidae. Most recently, placentotrophy has been described in five species of Poecilia (Pamphorichthys), but only one of these (P.hasemani) shows evidence of superfetation. Here, we use a molecular phylogeny based on concatenated nuclear and mitochondrial gene sequences to test hypotheses of correlated evolution between superfetation and placentotrophy in Poecilia. Taxon sampling included all species in the subgenera Micropoecilia and Pamphorichthys for which the presence or absence of placentotrophy and superfetation have been determined, as well as representatives of all other Poecilia subgenera (Acanthophacelus, Limia, Mollienesia, Poecilia, Pseudolimia). Phylogenetic analyses were performed with maximum parsimony, maximum likelihood, and Bayesian methods; ancestral states for life-history characters were reconstructed with parsimony and SIMMAP; correlation analyses were performed with SIMMAP; and divergence times were estimated using a relaxed molecular clock. All subgenera in Poecilia were recovered as monophyletic. The basal split in Poecilia is between P. (Acanthophacelus)+P. (Micropoecilia) and the other five subgenera. In the latter clade, P. (Poecilia) is the sister-group to the remaining four subgenera. Within P. (Pamphorichthys), all analyses with the combined data set recovered P. (Pamphorichthys) araguaiensis as the sister taxon to P. (Pamphorichthys) hollandi, and P. (Pamphorichthys) scalpridens as the sister taxon to P. (Pamphorichthys) minor. P. (Pamphorichthys) hasemani was either the sister taxon to P. (Pamphorichthys) hollandi+P. (Pamphorichthys) minor (maximum likelihood, Bayesian) or the sister taxon to all other Pamphorichthys species (maximum parsimony). Ancestral state reconstructions suggest that placentotrophy and superfetation evolved on the same branch in P. (Micropoecilia), whereas placentotrophy evolved before superfetation in P. (Pamphorichthys). SIMMAP analyses indicate a statistically significant association between placentotrophy and superfetation. Within P. (Micropoecilia) both placentotrophy and superfetation evolved in ≤4 million years. Within P. (Pamphorichthys), superfetation evolved in ≤9 million years on the P. (Pamphorichthys) hasemani branch, and placentotrophy evolved in ≤10 million years in the common ancestor of this subgenus.

Negative correlations can play a positive role in disordered quantum walks.

We investigate the emerging properties of quantum walks with temporal disorder engineered from a binary Markov chain with tailored correlation, C, and disorder strength, r. We show that when the disorder is weak-[Formula: see text]-the introduction of negative correlation leads to a counter-intuitive higher production of spin-lattice entanglement entropy, [Formula: see text], than the setting with positive correlation, that is [Formula: see text]. These results show that negatively correlated disorder plays a more important role in quantum entanglement than it has been assumed in the literature.

Antivax movement and epidemic spreading in the era of social networks: Nonmonotonic effects, bistability, and network segregation.

In this work, we address a multicoupled dynamics on complex networks with tunable structural segregation. Specifically, we work on a networked epidemic spreading under a vaccination campaign with agents in favor and against the vaccine. Our results show that such coupled dynamics exhibits a myriad of phenomena such as nonequilibrium transitions accompanied by bistability. Besides we observe the emergence of an intermediate optimal segregation level where the community structure enhances negative opinions over vaccination but counterintuitively hinders-rather than favoring-the global disease spreading. Thus our results hint vaccination campaigns should avoid policies that end up segregating excessively antivaccine groups so that they effectively work as echo chambers in which individuals look to confirmation without jeopardizing the safety of the whole population.

Molecular phylogenetic relationships and the evolution of the placenta in Poecilia (Micropoecilia) (Poeciliidae: Cyprinodontiformes).

Poeciliids are one of the most intensively studied groups within Cyprinodontiformes owing to their use as model organisms for experimental studies on natural and sexual selection, and comparative studies of life-history evolution. Life-history studies have demonstrated multiple origins of placentotrophy and superfetation in poeciliids, including the recent description of placentotrophy in three species of Poecilia (Micropoecilia): P. bifurca, P. branneri, and P. parae. Here, we use a concatenation of seven nuclear gene segments and two mitochondrial segments to examine relationships within Micropoecilia and between this subgenus and other subgenera in Poecilia (Mollienesia, Limia, Pamphorichthys, Acanthophacelus). The combined molecular data set (8668 bp) was analyzed with maximum parsimony, maximum likelihood, and Bayesian methods. We also employed a relaxed molecular clock method to estimate divergence times within Poecilia. All phylogenetic analyses with the combined DNA data set supported the monophyly of Poecilia and recovered a basal split between Poecilia (Acanthophacelus)+Poecilia (Micropoecilia) and the other three subgenera. Within Micropoecilia, P. bifurca grouped with P. branneri, and these joined P. parae to the exclusion of P. picta. Ancestral reconstructions based on parsimony and Bayesian methods suggest that placentotrophy evolved once in Micropoecilia in the common ancestor of P. bifurca, P. branneri, and P. parae. Divergence time estimates suggest that placentotrophy in Micropoecilia evolved in 4 million years.

Parrondo's paradox in quantum walks with time-dependent coin operators.

We show that a Parrondo paradox can emerge in two-state quantum walks without resorting to experimentally intricate high-dimensional coins. To achieve such goal we employ a time-dependent coin operator without breaking the translation spatial invariance of the system.

Optimal dispersal in ecological dynamics with Allee effect in metapopulations.

We introduce a minimal agent-based model to understand the effects of the interplay between dispersal and geometric constraints in metapopulation dynamics under the Allee Effect. The model, which does not impose nonlinear birth and death rates, is studied both analytically and numerically. Our results indicate the existence of a survival-extinction boundary with monotonic behavior for weak spatial constraints and a nonmonotonic behavior for strong spatial constraints so that there is an optimal dispersal that maximizes the survival probability. Such optimal dispersal has empirical support from recent experiments with engineered bacteria.

Multiple transitions between normal and hyperballistic diffusion in quantum walks with time-dependent jumps.

We extend to the gamut of functional forms of the probability distribution of the time-dependent step-length a previous model dubbed Elephant Quantum Walk, which considers a uniform distribution and yields hyperballistic dynamics where the variance grows cubicly with time, σ2 ∝ t3, and a Gaussian for the position of the walker. We investigate this proposal both locally and globally with the results showing that the time-dependent interplay between interference, memory and long-range hopping leads to multiple transitions between dynamical regimes, namely ballistic → diffusive → superdiffusive → ballistic → hyperballistic for non-hermitian coin whereas the first diffusive regime is quelled for implementations using the Hadamard coin. In addition, we observe a robust asymptotic approach to maximal coin-space entanglement.

Three-state opinion dynamics in modular networks.

In this work we study the opinion evolution in a community-based population with intergroup interactions. We address two issues. First, we consider that such intergroup interactions can be negative with some probability p. We develop a coupled mean-field approximation that still preserves the community structure and it is able to capture the richness of the results arising from our Monte Carlo simulations: continuous and discontinuous order-disorder transitions as well as nonmonotonic ordering for an intermediate community strength. In the second part, we consider only positive interactions but with the presence of inflexible agents holding a minority opinion. We also consider an indecision noise: a probability q that allows the spontaneous change of opinions to the neutral state. Our results show that the modular structure leads to a nonmonotonic global ordering as q increases. This inclination toward neutrality plays a dual role: A moderated propensity to neutrality helps the initial minority to become a majority, but this noise-driven opinion switching becomes less pronounced if the agents are too susceptible to become neutral.

Circulating levels of mannose-binding lectin (MBL) in age-related macular degeneration.

PURPOSE: To assess whether the serum levels of mannose-binding lectin of the lectin complement pathway are associated with age-related macular degeneration. METHODS: Patients with age-related macular degeneration and age-matched controls underwent full ophthalmologic examination and optical coherence tomography. Using a time-resolved immunofluorometric assay, blood samples were evaluated to determine the serum mannose-binding lectin levels. RESULTS: A total of 136 individuals were evaluated, including 68 patients with age-related macular degeneration (34 exudative and 34 nonexudative) and 68 age-matched controls. The median mannose-binding lectin level was 608 ng/mL (range, 30-3,415 ng/mL) in patients with age-related macular degeneration and 739 ng/mL (range, 30-6,039 ng/mL) in controls, with no difference between the groups. Additionally, the median mannose-binding lectin level was 476 ng/mL (range, 30-3,415 ng/mL) in exudative cases and 692 ng/mL (range, 30-2,587 ng/mL) in nonexudative cases. CONCLUSIONS: Serum mannose-binding lectin levels were not associated with age-related macular degeneration or with the exudative and nonexudative forms of the disease.

Breast cancer risk and polymorphisms in genes involved in metabolism of estrogens (CYP17, HSD17beta1, COMT and MnSOD): possible protective role of MnSOD gene polymorphism Val/Ala and Ala/Ala in women that never breast fed.

Polymorphisms in genes encoding enzymes involved in estrogen metabolism are held to be candidates for associations with breast disease, since there is evidence that circulating estrogens are associated with breast cancer risk. In this study, we evaluated the frequency of different polymorphisms related with estrogen metabolism [COMT Val158Met, CYP17 (5'UTR, T27C); HSD17beta1 Gly313Ser and MnSOD Val16Ala] in a breast cancer resistant population, the Xavante Indians, and the frequencies were compared with the ones reported in other populations where breast cancer case-control studies dealing with these polymorphisms have been carried out. The data obtained showed that, apart from the MnSOD Val16Ala polymorphism where the frequency of the variant allele was much higher than that reported in other populations, all the others were within the range reported in other populations. Considering these data we carried out a case-control study in the Portuguese population (241 cases and 457 controls) in order to evaluate the potential role of this polymorphism in breast cancer susceptibility. The results obtained did not reveal a significant association between individual genotypes and breast cancer risk. However, when the population was stratified for breast feeding, it was observed that for the patients that never breast fed the presence of the variant allele (Ala) was marginally associated with a decreased risk for this pathology (adjusted OR: 0.575 (0.327-1.011). These data seem to suggest that individuals who never breast fed with MnSOD Val16Ala variant allele are at a lower risk for breast cancer, but larger studies are required to confirm these results.

[Ulcerative esophagitis associated with the use of alendronate sodium: histopathological and endoscopic features]. / Esofagite ulcerativa associada ao uso de alendronato de sódio: achados histopatológicos e endoscópicos.

BACKGROUND: Drug-induced or "pill-induced" esophagitis may be secondary to the prolonged contact of the drug with the esophageal mucosa or secondary to the drug ability to alter the local conditions. The alendronate sodium, a bone resorption inhibitor used in the treatment and prevention of osteoporosis, has been cited, recently, as one of the causes of adverse upper gastrointestinal tract injury. AIM: To describe the clinical, endoscopic and histopathological features of patients with ulcerative esophagitis associated with alendronate sodium. PATIENTS: Four women and one man with osteoporosis were treated with alendronate sodium and submitted to endoscopy followed esophageal biopsy. RESULTS: The age range of the patients was from 64 to 84 years old. The patients showed dyspeptic symptoms after taking alendronate sodium during a period of 2-12 months. At endoscopic evaluation, the mucosa was friable, with erosion and/or ulceration covered by fibrin in the distal esophagus. The pathological examination of the esophageal biopsies revealed ulcerative esophagitis characterized by necrofibrinpurulent material, granulation tissue, and yellow refractile polarizable crystal. The patients' symptoms resolved after stopping alendronate sodium use. CONCLUSIONS: The esophagus injuries associated with alendronate sodium are not frequent and seem to be associated with the incorrect use of medication. The endoscopists and pathologists should be alert to the possibility of alendronate sodium therapy in cases of diagnosis of ulcerative esophagitis in ancient patients, particularly in women. The recognition of this condition would improve the patient care.

Circulating levels of mannose-binding lectin (MBL) in age-related macular degeneration / Níveis circulantes da lectina ligadora de manose (MBL) na degeneração macular relacionada à idade

ABSTRACT Purpose: To assess whether the serum levels of mannose-binding lectin of the lectin complement pathway are associated with age-related macular degeneration. Methods: Patients with age-related macular degeneration and age-matched controls underwent full ophthalmologic examination and optical coherence tomography. Using a time-resolved immunofluorometric assay, blood samples were evaluated to determine the serum mannose-binding lectin levels. Results: A total of 136 individuals were evaluated, including 68 patients with age-related macular degeneration (34 exudative and 34 nonexudative) and 68 age-matched controls. The median mannose-binding lectin level was 608 ng/mL (range, 30-3,415 ng/mL) in patients with age-related macular degeneration and 739 ng/mL (range, 30-6,039 ng/mL) in controls, with no difference between the groups. Additionally, the median mannose-binding lectin level was 476 ng/mL (range, 30-3,415 ng/mL) in exudative cases and 692 ng/mL (range, 30-2,587 ng/mL) in nonexudative cases. Conclusions: Serum mannose-binding lectin levels were not associated with age-related macular degeneration or with the exudative and nonexudative forms of the disease.

RESUMO Objetivos: Avaliar se as concentrações séricas da lectina ligante de manose da via das lectinas do sistema complemento estão associadas à degeneração macular relacionada à idade. Métodos: Pacientes com degeneração macular relacionada à idade a controles pareados realizaram exame oftalmológico completo e imagens de tomografia de coerência óptica. As concentrações de lectina ligante de manose foram aferidas em amostras de sangue pelo método "time-resolved Immunofluorometric assay". Resultados: Um total de 136 indivíduos foram avaliados incluindo 68 com degeneração macular relacionada à idade (34 exsudativa e 34 não-exsudativa) e 68 controles. Concentrações medianas de lectina ligante de ma-nose foram 608 ng/mL (30-3,415 ng/mL) nos casos e 739 ng/mL (30-6,039 ng/mL) nos controles, não havendo diferença entre os grupos. Comparando degeneração macular relacionada a idade exsudativa (mediana de lectina ligante de manose 476 ng/mL; 30-3,415 ng/mL) e não-exsudativa (692 ng/mL; 30-2,587 ng/mL) também não apresentaram diferença. Conclusões: Concentrações séricas de lectina ligante de manose não estão relacionadas à degeneração macular relacionada a idade ou às formas exsudativa e não-exsudativa.