31 research outputs found
Local variation of hashtag spike trains and popularity in Twitter
We draw a parallel between hashtag time series and neuron spike trains. In
each case, the process presents complex dynamic patterns including temporal
correlations, burstiness, and all other types of nonstationarity. We propose
the adoption of the so-called local variation in order to uncover salient
dynamics, while properly detrending for the time-dependent features of a
signal. The methodology is tested on both real and randomized hashtag spike
trains, and identifies that popular hashtags present regular and so less bursty
behavior, suggesting its potential use for predicting online popularity in
social media.Comment: 7 pages, 7 figure
Pure seminoma: A review and update
Pure seminoma is a rare pathology of the young adult, often discovered in the early stages. Its prognosis is generally excellent and many therapeutic options are available, especially in stage I tumors. High cure rates can be achieved in several ways: standard treatment with radiotherapy is challenged by surveillance and chemotherapy. Toxicity issues and the patients' preferences should be considered when management decisions are made. This paper describes firstly the management of primary seminoma and its nodal involvement and, secondly, the various therapeutic options according to stage
BMC Psychol
Background Preschoolers regularly display disruptive behaviors in child care settings because they have not yet developed the social skills necessary to interact prosocially with others. Disruptive behaviors interfere with daily routines and can lead to conflict with peers and educators. We investigated the impact of a social skills training program led by childcare educators on childrenâs social behaviors and tested whether the impact varied according to the childâs sex and family socio-economic status. Methods Nineteen public Child Care Centers (CCC, nâ=â361 children) located in low socio-economic neighborhoods of Montreal, Canada, were randomized into one of two conditions: 1) intervention (nâ= 10 CCC; 185 children) or 2) wait list control (nâ=â9 CCC; 176 children). Educators rated childrenâs behaviors (i.e., disruptive and prosocial behaviors) before and after the intervention. Hierarchical linear mixed models were used to account for the nested structure of the data. Results At pre-intervention, no differences in disruptive and prosocial behaviors were observed between the experimental conditions. At post-intervention, we found a significant sex by intervention interaction (ÎČ intervention by sexâ=âââ1.19, pâ=â0.04) indicating that girls in the intervention condition exhibited lower levels of disruptive behaviors compared to girls in the control condition (f2 effect sizeâ=âââ0.15). There was no effect of the intervention for boys. Conclusions Girls may benefit more than boys from social skills training offered in the child care context. Studies with larger sample sizes and greater intervention intensity are needed to confirm the results
ELASTIC SCATTERING FOR THE Be-11+Zn-64 SYSTEM CLOSE TO THE COULOMB BARRIER
The quasi-elastic scattering angular distribution of the collision 11Be + 64Zn was measured and compared with the elastic scattering angular distribution for its core, the 10Be nucleus on the same target. Optical model and continuum-discretized coupled-channel calculations of the 11Be+64Zn reaction were performed in order to interpret the effect of coupling with the break-up channels on the measured cross-sections.status: publishe
Elastic scattering of Beryllium isotopes near the Coulomb barrier
In this contribution, results of experiments performed with the three Beryllium isotopes 9,10,11Be on a medium mass 64Zn target, at a center of mass energy of â1.4 the Coulomb barrier, will be discussed. Elastic scattering angular distributions have been measured for the 9,10Be reactions. In the 11Be case the quasielastic scattering angular distribution was obtained. In the halo nucleus case, the angular distribution exhibit a non-Fresnel-type pattern with a strong damping of the Coulomb-nuclear interference peak. Moreover, it is found that the total reaction cross-section for the halo nucleus induced collision is more than double the ones extracted in the collisions induced by the non-halo Beryllium isotopes. A large contribution to the total-reaction cross-section in the 11Be case could be attributed to transfer and/or break-up events. © 2011 American Institute of Physics.status: publishe
Elastic Scattering and Reaction Mechanisms of the Halo Nucleus 11Be around the Coulomb Barrier
Collisions induced by 9,10,11Be on a 64Zn target at the same c.m. energy were studied. For the ïŹrst time,
strong effects of the 11Be halo structure on elastic-scattering and reaction mechanisms at energies near the
Coulomb barrier are evidenced experimentally. The elastic-scattering cross section of the 11Be halo
nucleus shows unusual behavior in the Coulomb-nuclear interference peak angular region. The extracted
total-reaction cross section for the 11Be collision is more than double the ones measured in the collisions
induced by 9,10Be. It is shown that such a strong enhancement of the total-reaction cross section with 11Be
is due to transfer and breakup processes.status: publishe
Dynamic-Sensitive centrality of nodes in temporal networks
Locating influential nodes in temporal networks has attracted a lot of attention as data driven and diverse applications. Classic works either looked at analysing static networks or placed too much emphasis on the topological information but rarely highlighted the dynamics. In this paper, we take account the network dynamics and extend the concept of Dynamic-Sensitive centrality to temporal network. According to the empirical results on three real-world temporal networks and a theoretical temporal network for susceptible-infected-recovered (SIR) models, the temporal Dynamic-Sensitive centrality (TDC) is more accurate than both static versions and temporal versions of degree, closeness and betweenness centrality. As an application, we also use TDC to analyse the impact of time-order on spreading dynamics, we find that both topological structure and dynamics contribute the impact on the spreading influence of nodes, and the impact of time-order on spreading influence will be stronger when spreading rate b deviated from the epidemic threshold b(c), especially for the temporal scale-free networks