2,809 research outputs found
Evolutionary of Online Social Networks Driven by Pareto Wealth Distribution and Bidirectional Preferential Attachment
Understanding of evolutionary mechanism of online social networks is greatly
significant for the development of network science. However, present researches
on evolutionary mechanism of online social networks are neither deep nor clear
enough. In this study, we empirically showed the essential evolution
characteristics of Renren online social network. From the perspective of Pareto
wealth distribution and bidirectional preferential attachment, the origin of
online social network evolution is analyzed and the evolution mechanism of
online social networks is explained. Then a novel model is proposed to
reproduce the essential evolution characteristics which are consistent with the
ones of Renren online social network, and the evolutionary analytical solution
to the model is presented. The model can also well predict the ordinary
power-law degree distribution. In addition, the universal bowing phenomenon of
the degree distribution in many online social networks is explained and
predicted by the model. The results suggest that Pareto wealth distribution and
bidirectional preferential attachment can play an important role in the
evolution process of online social networks and can help us to understand the
evolutionary origin of online social networks. The model has significant
implications for dynamic simulation researches of social networks, especially
in information diffusion through online communities and infection spreading in
real societies.Comment: 19 pages, 8 figures,31 reference
Oscillation of solutions of some higher order linear differential equations
In this paper, we deal with the order of growth and the hyper order of solutions of higher order linear differential equations where and are entire functions or polynomials. Some results are obtained which improve and extend previous results given by Z.-X. Chen, J. Wang, T.-B. Cao and C.-H. Li
Bounds for the sums of zeros of solutions of where is a polynomial
The main purpose of this paper is to consider the differential equation where is a polynomial with in general complex coefficients. Let be the zeros of a nonzero solution to that equation. We obtain bounds for the sums which extend some recent results proved by Gil'
Involvement of Fenton chemistry in rice straw degradation by the lignocellulolytic bacterium Pantoea ananatis Sd-1
Additional file 7: Table S2. Primers used for quantitative real time-PCR
Uniqueness and value distribution for q-shifts of meromorphic functions
In this paper, we deal with value distribution for q-shift polynomials of transcendental meromorphic functions with zero order and obtain some results which improve the previous theorems given by Liu and Qi [18]. In addition, we investigate value sharing for q-shift polynomials of transcendental entire functions with zero order and obtain some results which extend the recent theorem given by Liu, Liu and Cao [17]
Benzoxime inhibits matrix metalloproteinase-13 activation and cartilage damage in osteoarthritis rats via inhibition of NF-κB pathway
Purpose: To investigate the effect of benzoxime on degradation of articular cartilage in a rat model of osteoarthritis (OA), and the mechanism involved.Methods: The OA rat model was prepared by injecting monosodium iodoacetate (MIA) intra-articularly to Wistar rats. Rats in the treatment group were given benzoxime (5 mg/kg) daily for 21 days through the intra-articular route. The animals were then examined for behavioral changes by assessment of asymmetry in bearing weight and paw withdrawal threshold of the hind limb. Western blot assay was used for the analysis of inflammatory cytokine expressions.Results: The expression of P2X purinoceptor 7 receptor (P2X7R) mRNA was significantly elevated in the OA rats (p < 0.02). However, benzoxime treatment caused a marked decrease in the level of P2X1-8R mRNA. Benzoxime treatment also prevented asymmetry in bearing weight, decreased paw withdrawal threshold, and inhibited the expressions of interleukin-1β, interleukin-6 and tumor necrosis factor-α in plasma and cartilage. Moreover, benzoxime exhibited significant inhibitory effects on the expressions of P2X7R, matrix metalloproteinase (MMP)-13 and prostaglandin E2 (PGE2) in cartilage tissue. It also significantly suppressed OA-induced increases in the levels of inhibitor of nuclear factor-κB (NF-κB) kinase (IKK)α, IKKβ, IκBα and NF-κB p65, and blocked OA-induced increases in the expressions of P2X7R, MMP-13 and PGE2.Conclusion: These results demonstrate that benzoxime prevents cartilage degradation in OA rats by targeting NF-κB signaling pathway. Thus, benzoxime possesses clinical and therapeutic potentials for the prevention of cartilage degradation in OA.Keywords: Interleukin-1β, Purinoceptor-7, Benzoxime, Osteoarthritis, Prostaglandin, Matrix metalloproteinase
Antitumor Cyclic Hexapeptides from Rubia Plants: History, Chemistry, and Mechanism (2005–2011)
Rubiaceae-type cyclopeptides (RAs), cyclic hexapeptides from Rubia plants, have shown potential antitumor activity in vitro and in vivo. Based on the review about plant cyclopeptides (Chem. Rev., 2006, 106: 840), this mini-review will highlight new
progress on the discovery, synthesis, and mechanism of RAs isolated during 2005 to 2011, covering recent work in our group
Study on the One-Proton Halo Structure in Al
The Glauber theory has been used to investigate the reaction cross section of
proton-rich nucleus Al. A core plus a proton structure is assumed for
Al. HO-type density distribution is used for the core while the density
distribution for the valence proton is calculated by solving the eigenvalue
problem of Woods-Saxon potential. The transparency function in an analytical
expression is obtained adopting multi-Gaussian expansion for the density
distribution. Coulomb correction and finite-range interaction are introduced.
This modified Glauber model is apt for halo nuclei. A dominate s-wave is
suggested for the last proton in Al from our analysis which is possible
in the RMF calculation.Comment: 4 pages, 4 figure
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