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The interaction between different cations and certain aromatic dimers (benzene, naphthalene, anthracene) and heteroaromatic dimers (pyridine, pyrazine, sym-triazine and sym-tetrazine) has been investigated employing the MP2 level ...
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The interaction between different cations and certain aromatic dimers (benzene, naphthalene, anthracene) and heteroaromatic dimers (pyridine, pyrazine, sym-triazine and sym-tetrazine) has been investigated employing the MP2 level of theory with the 6-31G** and 6-311++G** basis sets. The trend in the stabilization energy for aromatic dimers is found to be: (anthracene)2-cation(naphthalene)2-cation(benzene)2-cation. In all three cases, the cation remains sandwiched between the rings. In the case of the heteroaromatic systems, on the other hand, the cation prefers to interact with the nitrogen atom of the ring. These results can be rationalized by molecular electrostatic potential maps for the systems under consideration. In addition, these results are in conformity with the available cation aromatic database.
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The behavioural adaptation (movement and habitat utilization) of translocated organisms to a new environment after their release is crucial in translocation programs because it may affect survival. Therefore, identifying the facto...
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The behavioural adaptation (movement and habitat utilization) of translocated organisms to a new environment after their release is crucial in translocation programs because it may affect survival. Therefore, identifying the factors determining habitat selection by the relocated animals is essential to improving the planning and the outcome of such programs. Using the data from three relocated giant pandas (Ailuropoda melanoleuca), we studied the habitat utilization, release-site fidelity, and interaction with resident giant pandas. The results showed that the quality of habitat used by the relocated giant pandas was significantly higher than the average habitat quality of the research region, and was significantly lower than that used by resident giant pandas. This suggested that the released three giant pandas had habitat selection abilities. The three released giant pandas gradually moved away from their release sites and did not exhibit site fidelity. In the first six months, the giant pandas stayed within about 3 km of their release sites, where habitat was good quality but overlapped with the distribution of resident giant pandas. The overlap of location between released and resident giant pandas decreased after six months when the released giant pandas moved away from their release sites.
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Upward flame spread and flame interactions over multiple solid fuels are experimentally studied, and the effects of flame interactions on the flame spreading rates are analyzed. Flame spreading characteristics and spreading rates ...
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Upward flame spread and flame interactions over multiple solid fuels are experimentally studied, and the effects of flame interactions on the flame spreading rates are analyzed. Flame spreading characteristics and spreading rates are measured and compared for six different geometric arrangements of thin solids at different solid width and separation distance between solids. The flame spread rate increases as the separation distance between the parallel solids decreases because of the flow channeling effect and radiation interactions, which reaches the maximum at an intermediate separation distance and then decreases as the separation distance becomes smaller due to the flow resistance and limited thermal expansion. To compare the six types of solid geometry studied, the highest flame spread rate is enclosure type of solids, followed by n-shaped solids, four parallel solids, two parallel solids, L-shaped solids, and single solid.
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We address the hydrodynamics of operator spreading in interacting integrable lattice models. In these models, operators spread through the ballistic propagation of quasiparticles, with an operator front whose velocity is locally s...
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We address the hydrodynamics of operator spreading in interacting integrable lattice models. In these models, operators spread through the ballistic propagation of quasiparticles, with an operator front whose velocity is locally set by the fastest quasiparticle velocity. In interacting integrable systems, this velocity depends on the density of the other quasiparticles, so equilibrium density fluctuations cause the front to follow a biased random walk, and therefore to broaden diffusively. Ballistic front propagation and diffusive front broadening are also generically present in nonintegrable systems in one dimension; thus, although the mechanisms for operator spreading are distinct in the two cases, these coarse-grained measures of the operator front do not distinguish between the two cases. We present an expression for the front-broadening rate; we explicitly derive this for a particular integrable model (the "Floquet-Fredrickson-Andersen" model), and argue on kinetic grounds that it should apply generally. Our results elucidate the microscopic mechanism for diffusive corrections to ballistic transport in interacting integrable models.
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Sina Weibo, one of the biggest social services in China, provides users with opportunities to share information and express their personal views, leading an explosive growth of information. How to recommend the right information t...
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Sina Weibo, one of the biggest social services in China, provides users with opportunities to share information and express their personal views, leading an explosive growth of information. How to recommend the right information to the proper person among massive data has received considerable critical attention in recent years. One of the main obstacles is the access to user topic interests. In this paper, we proposed an algorithm based on tags and bidirectional interactions to mine user topic interests on Sina Weibo. The algorithm, formulated by user interaction graph, fully takes advantage of the discordance between user interactions. Forward spread and back spread are thus utilized to update tag spread weights. We also quantify the impact of these two spread by tuning parameters on three sub data sets. In order to prove the superiority of the algorithm, we compare our algorithm with famous methods on Sina Weibo. The result demonstrates that our new algorithm outperforms other methods both in precision rate and recall rate, with the ability of mining user interest effectively with respect to tags and bidirectional interactions.
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The spreading dynamics of small polydimethylsiloxane (PDMS) drops was studied on substrates with varying surface energies. For experimental parameters near the wetting transition, we observed small PDMS drops of different drop vol...
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The spreading dynamics of small polydimethylsiloxane (PDMS) drops was studied on substrates with varying surface energies. For experimental parameters near the wetting transition, we observed small PDMS drops of different drop volumes as a function of time using interference video microscopy. While for large drops the con- tact angle 9 decreases with the well-established power-law relation 9 ~ t-OJ (Tanner's law), the effect of dispersive van der Waals (VW) interactions must be taken into account when interpreting the evolu- tion of small drops. Two signatures of the VW forces are observed. For a positive Hamaker constant, the disjoining pressure acts as an additional driving force, leading to an acceleration of droplet spreading as soon as the drop height becomes comparable to the range of the VW interactions. In addition, a precursor film forms ahead of the contact line, leading to an apparent volume loss, par- ticularly noticeable for very small drops. Contact line pinning may be a problem and we describe its effect on our experimental results. We present a theory that discusses the interplay of surface tension and VW forces in the case of a spreading drop. This model predicts a new spreading regime for very thin drops, in agreement with our experimental results.
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This paper is concerned with the minimal wave speed of traveling wave solutions of a discrete competitive system with Lotka-Volterra type nonlinearity. By constructing upper and lower solutions, we confirm the existence of traveli...
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This paper is concerned with the minimal wave speed of traveling wave solutions of a discrete competitive system with Lotka-Volterra type nonlinearity. By constructing upper and lower solutions, we confirm the existence of traveling wave solutions if the wave speed is the minimal wave speed. Our results complete the earlier conclusions.
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We investigate two-dimensional Ising systems with multispin interactions of three- (m = 3) and four-body terms (m = 4). The application of a new type of finite-size algorithm of de Oliveira allow us to clearly distinguish a first-...
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We investigate two-dimensional Ising systems with multispin interactions of three- (m = 3) and four-body terms (m = 4). The application of a new type of finite-size algorithm of de Oliveira allow us to clearly distinguish a first-order transition (in the m = 4 case) from a continuous one (in the m = 3 one). We also study the damage spreading in these systems. In this study, a dynamical phenomenon is observed to occur at a critical point separating a chaotic phase from a frozen one. However, the width of the interval where this transition happens does not yield a conclusive evidence about the order of the phase transition. (C) 1998 Elsevier Science B.V. All rights reserved. [References: 23]
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In this paper, based on susceptible-infected-susceptible (SIS) scheme, we introduce a framework that allows us to describe the spreading dynamics of two interacting diseases with active nodes. Different from previous studies, the ...
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In this paper, based on susceptible-infected-susceptible (SIS) scheme, we introduce a framework that allows us to describe the spreading dynamics of two interacting diseases with active nodes. Different from previous studies, the two different diseases, propagating concurrently on the same population, can interact with each other by modifying their transmission rates. Meanwhile, according to certain probabilities, each node on the complex networks rotates between active state and inactive state. Based on heterogeneous mean-field approach, we analyze the epidemic thresholds of the two diseases and compute the temporal evolution characterizing the spreading dynamics. In addition, we validate these theoretical predictions by numerical simulations with phase diagrams. Results show that the secondary thresholds for the two opposite scenarios (mutual enhancement scenario and mutual impairment scenario) are different. We also find that the value of critical threshold and the final size of spreading dynamics are reduced as the node activity rate decreases.
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In this paper, we consider a pair of homogeneous diseases spreading concurrently on uniform networks based on the SIS model. A new model describing the transmission process of the interacting diseases is established. The influence...
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In this paper, we consider a pair of homogeneous diseases spreading concurrently on uniform networks based on the SIS model. A new model describing the transmission process of the interacting diseases is established. The influence of the transmission parameters, the interacting parameter and the initial density value of infected nodes on the epidemic spreading is presented by simulating the transmission process of the proposed model. The mathematical expressions of the conditions among the transmission parameters, the interacting parameter and the network parameter when diseases can exist in the network based on the simplified model are presented. Comparing the transmission process of this interacting model under different intervals of the interacting parameter, it is found that the interacting of the two diseases leads to larger scale prevalence with a relatively larger interacting parameter when the infection breaks out.
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