A new stegosaur (Dinosauria: Ornithischia) from the Middle Jurassic of Gansu Province, China.

Stegosaurs are a minor but iconic clade of ornithischian dinosaurs, yet due to a poor fossil record, their early evolution is poorly understood. Here, we describe a new stegosaur, Baiyinosaurus baojiensis, gen. et sp. nov. from the Middle Jurassic Wangjiashan Formation of the Pingchuan District, Baiyin City, Gansu Province, China. The frontal of Baiyinosaurus possesses a unique characteristic among Stegosauria: it is wider than long and contributes to both the medial and anterior margins of the supratemporal fenestra. The character combinations of dorsal vertebrae of Baiyinosaurus are also different to other stegosaurs: its neural arches are not greatly elongated, its parapophyses are well developed, and its neural spines are axially expanded in lateral. The features of the frontal and vertebrae of Baiyinosaurus are reminiscent of basally branching thyreophorans, indicating that Baiyinosaurus is transitional in morphology between early thyreophorans and early-diverging stegosaurs. Systematic analysis shows that Baiyinosaurus is an early-diverging stegosaur.

Observability Transitions in Networks with Betweenness Preference.

A network is considered observable if its current state can be determined in finite time from knowledge of the observed states. The observability transitions in networks based on random or degree-correlated sensor placement have recently been studied. However, these placement strategies are predominantly based on local information regarding the network. In this paper, to understand the phase transition process of network observability, we analyze the network observability transition for a betweenness-based sensor placement strategy, in which sensors are placed on nodes according to their betweenness. Using numerical simulations, we compute the size of the network's largest observable component (LOC) and compare the observability transitions for different sensor placements. We find that betweenness-based sensor placement can generate a larger LOC in the observability transition than the random or degree-based placement strategy in both model and real networks. This finding may help to understand the relationship between network observability and the topological properties of the network.

Spatial correlation analysis of cascading failures: congestions and blackouts.

Cascading failures have become major threats to network robustness due to their potential catastrophic consequences, where local perturbations can induce global propagation of failures. Unlike failures spreading via direct contacts due to structural interdependencies, overload failures usually propagate through collective interactions among system components. Despite the critical need in developing protection or mitigation strategies in networks such as power grids and transportation, the propagation behavior of cascading failures is essentially unknown. Here we find by analyzing our collected data that jams in city traffic and faults in power grid are spatially long-range correlated with correlations decaying slowly with distance. Moreover, we find in the daily traffic, that the correlation length increases dramatically and reaches maximum, when morning or evening rush hour is approaching. Our study can impact all efforts towards improving actively system resilience ranging from evaluation of design schemes, development of protection strategies to implementation of mitigation programs.

[Effects of tetrandrine on enhancing radiosensitivity of human nasopharyngeal carcinoma cells].

OBJECTIVE: To study the effect and mechanism of tetrandrine (Tet) on enhancing radiosensitivity of human nasopharyngeal carcinoma cell lines in vitro. METHODS: CNE1 and CNE2 were exposed to radiation with or without Tet, the DNA damage of the cells were evaluated by neutral comet electrophoresis, and cell cycle and apoptosis were analyzed by flow cytometry. RESULTS: The mean tail movements (TM) of CNE1 treated with radiation or radiation plus Tet were (7.13 ± 3.70) (X(-) ± s) and (13.61 ± 5.45), respectively (t = 2.784, P < 0.05), and TM of CNE2 treated with radiation or radiation plus Tet were (11.52 ± 4.04) and (18.85 ± 6.18), respectively (t = 3.089, P < 0.05). With the exposure to radiation or radiation plus Tet, the percentages of CNE1 in G2 phases were (42.62 ± 2.07)% and (17.02 ± 1.87)%, respectively (t = 23.173, P < 0.01), and the percentages of CNE2 in G2 phases were (34.82 ± 2.74)% and (19.64 ± 4.82)%, respectively(t = 16.500, P < 0.01). There was no significant difference in the apoptosis rates between the cells treated with radiation or radiation plus Tet regardless of CNE1 (17.24 ± 0.99)% vs (19.11 ± 1.24)%, and CNE2 (16.68 ± 0.27)% vs (18.51 ± 2.41)% (P > 0.05). CONCLUSIONS: Tet can enhance radiosensitivity of human nasopharyngeal carcinoma cell lines. The mechanism could be related to abrogation of radiation-induced G2/M arrest and reduction of double-strand break repair capacity.