Network dynamics of ongoing social relationships

Many recent large-scale studies of interaction networks have focused on networks of accumulated contacts. In this paper we explore social networks of ongoing relationships with an emphasis on dynamical aspects. We find a distribution of response times (times between consecutive contacts of different direction between two actors) that has a power-law shape over a large range. We also argue that the distribution of relationship duration (the time between the first and last contacts between actors) is exponentially decaying. Methods to reanalyze the data to compensate for the finite sampling time are proposed. We find that the degree distribution for networks of ongoing contacts fits better to a power-law than the degree distribution of the network of accumulated contacts do. We see that the clustering and assortative mixing coefficients are of the same order for networks of ongoing and accumulated contacts, and that the structural fluctuations of the former are rather large.Comment: to appear in Europhys. Let

Controlling cluster synchronization by adapting the topology

We suggest an adaptive control scheme for the control of zero-lag and cluster synchronization in delay-coupled networks. Based on the speed-gradient method, our scheme adapts the topology of a network such that the target state is realized. It is robust towards different initial condition as well as changes in the coupling parameters. The emerging topology is characterized by a delicate interplay of excitatory and inhibitory links leading to the stabilization of the desired cluster state. As a crucial parameter determining this interplay we identify the delay time. Furthermore, we show how to construct networks such that they exhibit not only a given cluster state but also with a given oscillation frequency. We apply our method to coupled Stuart-Landau oscillators, a paradigmatic normal form that naturally arises in an expansion of systems close to a Hopf bifurcation. The successful and robust control of this generic model opens up possible applications in a wide range of systems in physics, chemistry, technology, and life science

Networking Effects on Cooperation in Evolutionary Snowdrift Game

The effects of networking on the extent of cooperation emerging in a competitive setting are studied. The evolutionary snowdrift game, which represents a realistic alternative to the well-known Prisoner's Dilemma, is studied in the Watts-Strogatz network that spans the regular, small-world, and random networks through random re-wiring. Over a wide range of payoffs, a re-wired network is found to suppress cooperation when compared with a well-mixed or fully connected system. Two extinction payoffs, that characterize the emergence of a homogeneous steady state, are identified. It is found that, unlike in the Prisoner's Dilemma, the standard deviation of the degree distribution is the dominant network property that governs the extinction payoffs.Comment: Changed conten

Histologic study of ossification of the thyroid cartilage

The process of ossification and formation of bone marrow occurs in the larynx cartilages with age. The knowledge of this change is important for differentiation with cartilage invasion by cancer. AIM: Cranial and caudal segments of the thyroid cartilage were obtained from adult male larynges in order to evaluate comparatively the histological changes regarding to the ossification and the bone marrow formation. STUDY DESIGN: Experimental. MATERIAL AND METHOD: Seven male adult larynges were obtained from cadavers underwent necrological examination in Posto Médico-Legal de Santos, da Polícia Civil do Estado de São Paulo. The ages ranged from 39 to 60, with median of 53. There were no available data about tobacco and alcohol consumption. The specimens underwent decalcification and stained with H-E. Histometry was performed for quantitative analysis of the ossification while the bone marrow was analyzed according to qualitative criteria (presence or absence). RESULTS: The average ossification was 42.8% and the bone marrow presence was observed in 57.1% in the cranial segments. In the caudal segments, the average ossification was 72.8%, and the bone marrow was detected in 87.5% of the specimens. CONCLUSION: The ossification in the thyroid cartilage and the bone marrow formation increase and occur earlier moving downward from the cranial to the caudal aspects.Com o passar da idade, ocorrem progressivamente ossificação e formação de medula óssea nas cartilagens laríngeas. O conhecimento dessas modificações é importante para a diferenciação com invasão por câncer. OBJETIVO: Avaliar comparativamente as porções cranial e caudal da cartilagem tireóidea quanto a alterações histológicas em indivíduos adultos do sexo masculino, observando a ossificação e a formação de medula óssea. FORMA DE ESTUDO: Experimental. MATERIAL E MÉTODO: Foram estudadas 7 laringes obtidas de cadáveres do sexo masculino submetidos a exame necrológico no Posto Médico-Legal de Santos, da Polícia Civil do Estado de São Paulo. A idade variou de 39 a 60 anos, com mediana de 53. Não se teve acesso à informação de hábito de tabagismo e etilismo. Os espécimes foram descalcificados e corados pela hematoxilina-eosina. A ossificação foi estudada pelo método histométrico baseado na estereologia e a presença de medula óssea foi realizada de forma qualitativa (presença ou ausência). RESULTADOS: Nos segmentos craniais, notamos uma média de 42,8% de ossificação e a presença de medula óssea em 57,1%. Nos segmentos caudais, a média de ossificação foi de 72,8%, com medula óssea em 87,5%. CONCLUSÃO: A ossificação da cartilagem tireóidea e a formação de medula óssea são mais intensas e precoces na sua topografia cranial.Hospital HeliópolisUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaHospital Ana Costa Serviço de Anatomia PatológicaUniversidade de São PauloUNIFESP, EPMSciEL

The remittances behaviour of the second generation in Europe: altruism or self-interest?

Whereas most research on remittances focuses on first-generation migrants, the aim of this paper is to investigate the remitting behaviour of the host country-born children of migrants - the second generation - in various European cities. Some important studies found that migrant transnationalism is not only a phenomenon for the first generation, but also apply to the second and higher generations, through, among other things, family visits, elder care, and remittances. At the same time, the maintenance of a strong ethnic identity in the ‘host’ society does not necessarily mean that second-generation migrants have strong transnational ties to their ‘home’ country. The data used in this paper is from “The Integration of the European Second Generation” (TIES) project. The survey collected information on approximately 6,250 individuals aged 18-35 with at least one migrant parent from Morocco, Turkey or former Yugoslavia, in 15 European cities, regrouped in 8 ‘countries’. For the purpose of this paper, only analyses for Austria (Linz and Vienna); Switzerland (Basle and Zurich); Germany (Berlin and Frankfurt); France (Paris and Strasbourg); the Netherlands (Amsterdam and Rotterdam); Spain (Barcelona and Madrid); and Sweden (Stockholm) will be presented.

Selective remodeling of cardiolipin fatty acids in the aged rat heart

BACKGROUND: The heart is rich in cardiolipin, a phospholipid acylated in four sites, predominately with linoleic acid. Whether or not aging alters the composition of cardiolipin acyl chains is controversial. We therefore measured the fatty acid concentration of cardiolipin in hearts of 4, 12 and 24 month old rats that consumed one diet, adequate in fatty acids for the duration of their life. RESULTS: The concentration (nmol/g) of linoleic acid was decreased in 24 month old rats (3965 ± 617, mean ± SD) vs 4 month old rats (5525 ± 656), while the concentrations of arachidonic and docosahexaenoic acid were increased in 24 month old rats (79 ± 9 vs 178 ± 27 and 104 ± 16 vs 307 ± 68 for arachidonic and docosahexaenoic acids, 4 months vs 24 months, respectively). Similar changes were not observed in ethanolamine glycerophospholipids or plasma unesterified fatty acids, suggesting specificity of these effects to cardiolipin. CONCLUSION: These results demonstrate that cardiolipin remodeling occurs with aging, specifically an increase in highly unsaturated fatty acids

Nash equilibria in quantum games with generalized two-parameter strategies

In the Eisert protocol for 2 X 2 quantum games [Phys. Rev. Lett. 83, 3077], a number of authors have investigated the features arising from making the strategic space a two-parameter subset of single qubit unitary operators. We argue that the new Nash equilibria and the classical-quantum transitions that occur are simply an artifact of the particular strategy space chosen. By choosing a different, but equally plausible, two-parameter strategic space we show that different Nash equilibria with different classical-quantum transitions can arise. We generalize the two-parameter strategies and also consider these strategies in a multiplayer setting.Comment: 19 pages, 2 eps figure

Two-Photon 2s<->1s Transitions during Recombination of Hydrogen in the Universe

Based on the standard cosmological model, we calculate the correction to the rate of two-photon 2s1s transitions in the hydrogen atom under primordial hydrogen plasma recombination conditions that arises when the induced transitions under equilibrium background radiation with a blackbody spectrum and plasma recombination radiation are taken into account.Comment: 20 pages, 9 figure

DeepBrain: Functional Representation of Neural In-Situ Hybridization Images for Gene Ontology Classification Using Deep Convolutional Autoencoders

This paper presents a novel deep learning-based method for learning a functional representation of mammalian neural images. The method uses a deep convolutional denoising autoencoder (CDAE) for generating an invariant, compact representation of in situ hybridization (ISH) images. While most existing methods for bio-imaging analysis were not developed to handle images with highly complex anatomical structures, the results presented in this paper show that functional representation extracted by CDAE can help learn features of functional gene ontology categories for their classification in a highly accurate manner. Using this CDAE representation, our method outperforms the previous state-of-the-art classification rate, by improving the average AUC from 0.92 to 0.98, i.e., achieving 75% reduction in error. The method operates on input images that were downsampled significantly with respect to the original ones to make it computationally feasible

Interlayer Registry Determines the Sliding Potential of Layered Metal Dichalcogenides: The case of 2H-MoS2

We provide a simple and intuitive explanation for the interlayer sliding energy landscape of metal dichalcogenides. Based on the recently introduced registry index (RI) concept, we define a purely geometrical parameter which quantifies the degree of interlayer commensurability in the layered phase of molybdenum disulphide (2HMoS2). A direct relation between the sliding energy landscape and the corresponding interlayer registry surface of 2H-MoS2 is discovered thus marking the registry index as a computationally efficient means for studying the tribology of complex nanoscale material interfaces in the wearless friction regime.Comment: 13 pages, 7 figure