Effects of organic nitrogen and carbon sources on mycelial growth and polysaccharides production and their optimization in the submerged culture of Grifola umbellate, a Chinese medicinal herb

Grifola umbellate is a famous and expensive Chinese herb medicine and the main medicinal component is polysaccharide mainly produced by its mycelia. Effects of organic nitrogen and carbon resources on mycelial growth and polysaccharides production of a medicinal mushroom, G. umbellate were studied in the submerged culture system. Soybean meal was selected as the optimal organic nitrogen source for its significant promotion effects on mycelial growth and polysaccharides synthesis based on results of an orthogonal matrix experiment design. Glucose was proved to be a preferred carbon source by comparison with fructose and sucrose. The optimal dosages of soybean meal 5.63% (w/v) and glucose 4.33% (w/v) were obtained, respectively through the curvilinear regressions experiment. The productions of mycelial dry weight, exo-polysaccharide (EPS) and inner polysaccharide (IPS), in the optimal medium, were about 3.16, 1.48 and 2.78 folds higher than those in the basal medium, respectively and culture duration was shortened to half through optimizing the organic nitrogen and carbon sources. These results will be significant contribution to process biochemistry of medicinal fungus in the submerged culture system

Notes on Ghost Dark Energy

We study a phenomenological dark energy model which is rooted in the Veneziano ghost of QCD. In this dark energy model, the energy density of dark energy is proportional to Hubble parameter and the proportional coefficient is of the order $\Lambda^3_{QCD}$, where $\Lambda_{QCD}$ is the mass scale of QCD. The universe has a de Sitter phase at late time and begins to accelerate at redshift around $z_{acc}\sim0.6$. We also fit this model and give the constraints on model parameters, with current observational data including SnIa, BAO, CMB, BBN and Hubble parameter data. We find that the squared sound speed of the dark energy is negative, which may cause an instability. We also study the cosmological evolution of the dark energy with interaction with cold dark matter.Comment: 20 pages,10 figures,Correct some typos and add new reference

Cosmological Evolution of Interacting Dark Energy Models with Mass Varying Neutrinos

In this paper we consider the cosmological implications of dark energy models with a coupled system of a dynamical scalar field (the quintessence) and the neutrinos. By detailed numerical calculations we study the various possibilities on the evolution and the fates of the universe in this class of models. Our results show that due to the interaction with quintessence, neutrinos could be dominant over the quintessence in the future universe, however would eventually decay away.Comment: One typographical error corrected, references updated and presentation improve

Improving the eco-environment in the western-China by applying local tree species: Issues and implications for global arid areas

Local tree species would perform an important role in forestation, because they have more advantages than exotic species in terms of the physiological and adaptation aspects. In this article, we discussed some main factors which affect the drought resistance of trees and depict some anti-droughtcharacteristics and mechanisms of some local species. These factors include osmoregulation, antioxidant system, transpiration and the shape and structure of trees. At the same time, we also make some suggestions and discussions for the application of typical local tree species in the west-China for improving regional, national and international environmental quality

Efficient routing on complex networks

In this letter, we propose a new routing strategy to improve the transportation efficiency on complex networks. Instead of using the routing strategy for shortest path, we give a generalized routing algorithm to find the so-called {\it efficient path}, which considers the possible congestion in the nodes along actual paths. Since the nodes with largest degree are very susceptible to traffic congestion, an effective way to improve traffic and control congestion, as our new strategy, can be as redistributing traffic load in central nodes to other non-central nodes. Simulation results indicate that the network capability in processing traffic is improved more than 10 times by optimizing the efficient path, which is in good agreement with the analysis.Comment: 4 pages, 4 figure

Ground state fidelity in bond-alternative Ising chains with Dzyaloshinskii-Moriya interactions

A systematic analysis is performed for quantum phase transitions in a bond-alternative one-dimensional Ising model with a Dzyaloshinskii-Moriya (DM) interaction by using the fidelity of ground state wave functions based on the infinite matrix product states algorithm. For an antiferromagnetic phase, the fidelity per lattice site exhibits a bifurcation, which shows spontaneous symmetry breaking in the system. A critical DM interaction is inversely proportional to an alternating exchange coupling strength for a quantum phase transition. Further, a finite-entanglement scaling of von Neumann entropy with respect to truncation dimensions gives a central charge c = 0.5 at the critical point.Comment: 6 pages, 4 figure