65 research outputs found
Cascading failures in coupled networks with both inner-dependency and inter-dependency links
We study the percolation in coupled networks with both inner-dependency and
inter-dependency links, where the inner- and inter-dependency links represent
the dependencies between nodes in the same or different networks, respectively.
We find that when most of dependency links are inner- or inter-ones, the
coupled networks system is fragile and makes a discontinuous percolation
transition. However, when the numbers of two types of dependency links are
close to each other, the system is robust and makes a continuous percolation
transition. This indicates that the high density of dependency links could not
always lead to a discontinuous percolation transition as the previous studies.
More interestingly, although the robustness of the system can be optimized by
adjusting the ratio of the two types of dependency links, there exists a
critical average degree of the networks for coupled random networks, below
which the crossover of the two types of percolation transitions disappears, and
the system will always demonstrate a discontinuous percolation transition. We
also develop an approach to analyze this model, which is agreement with the
simulation results well.Comment: 9 pages, 4 figure
Effects of heritability on evolutionary cooperation in spatial prisoner’s dilemma games
AbstractWe study the effects of heritability on the evolution of the spatial prisoner’s dilemma game. In our model, the fitness of each player is composed of the instantaneous payoff from the interactions and the inherited fitness from the last generation. Based on extensive simulations, we find that the density of cooperators is enhanced by increasing the heritability of players over a wide range of the model parameter. The mean fitness of cooperators and defectors are also studied for understanding our results
2-Amino-4-(4-bromophenyl)-6-ferrocenylpyridine-3-carbonitrile
The title compound, [Fe(C5H5)(C17H11BrN3)], was synthesized by the reaction of 4-bromobenzaldehyde, acetylferrocene and ammonium acetate in an aqueous medium. The crystal packing is stabilized by intermolecular N—H⋯N hydrogen bonds. The dihedral angles between the phenyl ring and the pyridine and cyclopentadienyl rings are 51.67 (13) and 12.12 (21)°, respectively
Information filtering based on transferring similarity
In this Brief Report, we propose a new index of user similarity, namely the
transferring similarity, which involves all high-order similarities between
users. Accordingly, we design a modified collaborative filtering algorithm,
which provides remarkably higher accurate predictions than the standard
collaborative filtering. More interestingly, we find that the algorithmic
performance will approach its optimal value when the parameter, contained in
the definition of transferring similarity, gets close to its critical value,
before which the series expansion of transferring similarity is convergent and
after which it is divergent. Our study is complementary to the one reported in
[E. A. Leicht, P. Holme, and M. E. J. Newman, Phys. Rev. E {\bf 73} 026120
(2006)], and is relevant to the missing link prediction problem.Comment: 4 pages, 4 figure
Personal Recommendation via Modified Collaborative Filtering
In this paper, we propose a novel method to compute the similarity between
congeneric nodes in bipartite networks. Different from the standard Person
correlation, we take into account the influence of node's degree. Substituting
this new definition of similarity for the standard Person correlation, we
propose a modified collaborative filtering (MCF). Based on a benchmark
database, we demonstrate the great improvement of algorithmic accuracy for both
user-based MCF and object-based MCF.Comment: 7 pages, 8 figures and 1 tabl
Transmission of plasmid-borne and chromosomal blaCTX-M-64 among Escherichia coli and Salmonella isolates from food-producing animals via ISEcp1-mediated transposition
Objectives: To clarify the transmission mechanism of the blaCTX-M-64 gene between Escherichia coli and Salmonella isolates from food animals. Methods: A total of 329 E. coli and 60 Salmonella isolates collected from food animals in 2016 were screened for the presence of blaCTX-M-64 genes. The blaCTX-M-64-positive isolates were typed and plasmid and chromosome DNA was sequenced to determine the genetic context of blaCTX-M-64 and the plasmid types present. Results: The blaCTX-M-64 gene was identified in only three E. coli isolates but was the predominant gene in the Salmonella isolates (n = 9). These 12 CTX-M-64-positive isolates were all resistant to ampicillin, cefotaxime, ceftiofur, ceftriaxone, ceftazidime and florfenicol and 9 were resistant to ciprofloxacin. The blaCTX-M-64 gene was located on transferable IncI2 plasmids and an IncHI2 plasmid in three E. coli and one Salmonella isolate, respectively. The remaining eight Salmonella isolates contained blaCTX-M-64 integrated into the chromosome. Different genetic contexts of blaCTX-M-64 genes were found among the 12 isolates: ISEcp1-blaCTX-M-64-orf477-A/C on IncI2 plasmids of 3 E. coli isolates; DISEcp1-blaCTX-M-64-orf477-A/C in the chromosome of 1 Salmonella isolate; and ISEcp1-blaCTX-M-64-orf477 on the IncHI2 plasmid and chromosome of 8 Salmonella isolates. Conclusions: To the best of our knowledge, this is the first report of chromosomally encoded CTX-M-64 in Salmonella isolates. ISEcp1-mediated transposition is likely to be responsible for the spread of blaCTX-M-64 between different plasmids and chromosomes in Enterobacteriaceae especially E. coli and Salmonella
The Bone-Protecting Efficiency of Chinese Medicines Compared With Western Medicines in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis of Comparative Studies
Background: Rheumatoid Arthritis (RA) is a systemic autoimmune disease leading to joint destruction. The prevention of bone and cartilage destruction has received increased attention in recent years.Objective: To evaluate the current evidences regarding the bone-protecting efficacy of Chinese medicine or the combination of Chinese medicine and Western medicine for RA.Methods: We comprehensively searched PubMed, Embase, the Cochrane Library (www.thecochranelibrary.com), the China National Knowledge Infrastructure (CNKI), the Database for Chinese Technical Periodicals (VIP), and SinoMed. We then performed a systematic review and cumulative meta-analysis of all randomized controlled trials (RCTs) assessing the two therapy methods.Results: Sixteen studies including 1,171 patients were included in the final analysis. The results showed that Chinese medicine could significantly improve the bone mineral density (BMD) (mean difference [MD] = 0.05 /g·cm−2, 95% CI [0.03, 0.08], P < 0.00001), and decrease the serum matrix metalloproteinase 3 (MMP-3) ([SMD] = −2.84, 95% CI [−4.22, −1.47], P < 0.0001).Conclusions: Chinese medicine may provide an efficiently alternative choice for the treatment of RA in terms of the bone-protecting efficiency. Given the inherent limitations of the included studies, future well-designed RCTs are required to confirm and update the findings of this analysis
Large-Scale Comparative Analyses of Tick Genomes Elucidate Their Genetic Diversity and Vector Capacities
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