Directional flow of solitons with asymmetric potential wells: Soliton diode

We study the flow of bright solitons through two asymmetric potential wells. The scattering of a soliton by certain type of single potential wells, e.g., Gaussian or Rosen-Morse, is distinguished by a critical velocity above which solitons can transmit almost completely and below which solitons can reflect nearly perfectly. For two such wells in series with certain parameter combinations, we find that there is an appreciable velocity range for which solitons can propagate in one direction only. Our study shows that this directional propagation or diode behavior is due to a combined effect of the sharp transition in the transport coefficients at the critical velocity and a slight reduction in the center-of-mass speed of the soliton while it travels across a potential well.Comment: 7 pages, 5 figure

RCD: Rapid Close to Deadline Scheduling for Datacenter Networks

Datacenter-based Cloud Computing services provide a flexible, scalable and yet economical infrastructure to host online services such as multimedia streaming, email and bulk storage. Many such services perform geo-replication to provide necessary quality of service and reliability to users resulting in frequent large inter- datacenter transfers. In order to meet tenant service level agreements (SLAs), these transfers have to be completed prior to a deadline. In addition, WAN resources are quite scarce and costly, meaning they should be fully utilized. Several recently proposed schemes, such as B4, TEMPUS, and SWAN have focused on improving the utilization of inter-datacenter transfers through centralized scheduling, however, they fail to provide a mechanism to guarantee that admitted requests meet their deadlines. Also, in a recent study, authors propose Amoeba, a system that allows tenants to define deadlines and guarantees that the specified deadlines are met, however, to admit new traffic, the proposed system has to modify the allocation of already admitted transfers. In this paper, we propose Rapid Close to Deadline Scheduling (RCD), a close to deadline traffic allocation technique that is fast and efficient. Through simulations, we show that RCD is up to 15 times faster than Amoeba, provides high link utilization along with deadline guarantees, and is able to make quick decisions on whether a new request can be fully satisfied before its deadline.Comment: World Automation Congress (WAC), IEEE, 201

Hepatoprotective effect and GC-MS analysis of traditionally used Boswellia sacra oleo gum resin (Frankincense) extract in

Background: The water extract of oleo-gum-resin of Boswellia sacra Fleuckiger (Burseraceae) is used in the treatment of liver problems in the Middle East and Arab-African countries. The present study was carried out to evaluate its effect on liver injury induced by carbon tetrachloride in acute and chronic liver injury models.Materials and Methods: The Boswellia sacra extract was administered at doses of 2 ml/kg and 5 ml/kg. Silymarin, a known hepato-protective agent was used as standard. The extract was subjected to GC-MS analysis to determine the presence of various phyto-constituents.Results: The Boswellia sacra extract at tested doses of 2 ml/kg and 5 ml/kg significantly reduced the elevated serum levels of biomarkers in liver damage. The hepatoprotective effect was supported by changes in histopathology. The GC-MS analysis of the extract revealed the presence of several phyto-constituents that included menthol, 3-cyclohexen-1-ol and octanoic acid.Conclusion: The water extract oleo-gum-resin of Boswellia sacra possesses hepatoprotective activity, as claimed by traditional healers within the Middle East and Arab-African countries.Key words: Boswellia sacra, hepatoprotective, carbon tetrachloride, frankincense, liver damage