Perplexing dynamics of Wolbachia proteins for cytoplasmic incompatibility

The mechanism of symbiont-induced cytoplasmic incompatibility (CI) has been a long-standing mystery. A new study on Wolbachia's Cif proteins in PLOS Biology provides supportive evidence for the "Host modification model, " although the alternative "Toxin-antidote model" is still in the running

Effect of high molecular weight hyaluronan on cartilage degeneration in a rabbit model of osteoarthritis

SummaryThe effects of high molecular weight hyaluronan (HA) on cartilage degeneration were investigated in a partial menisectomy model of osteoarthritis (OA) in the rabbit knee. This study compared HA80 (0.8 × 106 Da, 1%), HA190 (1.9 × 106 Da, 0.01–1%) and saline. HA (0.1 ml/kg) or saline were injected intra-articularly twice a week immediately after surgery. Degenerative changes in femoral and tibial cartilages were graded histopathologically 2 and 4 weeks after surgery. Two weeks after surgery, HA190, only when used at a 1% concentration, resulted in a dramatic inhibition of cartilage degeneration in both the femoral condyle and the tibial plateau (P < 0.01). Two weeks after surgery, the protection against cartilage degeneration was significantly (P < 0.05) greater with HA190 than with HA80. Four weeks after surgery, only the femoral cartilage degeneration was significantly and similarly inhibited with HA190 (P < 0.01) and HA80 (P < 0.05). Scanning electron micrographs of femoral cartilage showed that cartilage degeneration was less severe with HA190 than with saline. These results might suggest that, in the rabbit model, intra-articular administration of higher molecular weight HA is more effective than lower molecular weight HA in inhibiting cartilage degeneration in early OA

Perpendicular coercivity enhancement of CoPt/TiN films by nitrogen incorporation during deposition

The effect of N incorporation on the structure and magnetic properties of CoPt thin films deposited on glass substrates with TiN seed layers has been investigated. During the deposition of CoPt, introducing 20% N2 into Ar atmosphere promotes the (001) texture and enhances the perpendicular coercivity of CoPt film compared with the film deposited in pure Ar and post-annealed under the same conditions. From the in situ x-ray diffraction results, it is confirmed that N incorporation expands the lattice parameter of CoPt, which favors the epitaxial growth of CoPt on TiN. During the post-annealing process, N releases from CoPt film and promotes the L10 ordering transformation of CoPt. © 2015 AIP Publishing LLC

Architecture of Job scheduling simulator for demand response based resource provisioning

We study a new service model based on the Demand Response (DR) resource provisioning at High Performance Computing (HPC) centers. This DR-based resource provisioning model allows administrators of HPC centers to provide computing services with incentives to users to compensate for the performance loss due to power saving operations. In a power conservation mode, a job’s performance may decrease, both in terms of a job waiting time and a job execution time. With DR-based resource provisioning, the submitted jobs are divided into two categories, allowed jobs and disallowed jobs, depending on the user’s tolerance in the performance degradation. The allowed jobs, if indeed affected by the power saving operations, will receive compensation in accordance with an incentive system which determines the reward to the user. For designing an appropriate demand response model, we need to focus on the increase in the job’s execution time and the job’s waiting time, and the corresponding decrease in the power consumption. These are important factors in deriving an incentive system. Currently, no existing approaches can reliably quantify the effectiveness and the contribution of these factors in HPC job scheduling and resource provisioning. In this paper, we propose a newly developed job scheduling simulator that can evaluate DR-based resource provisioning approach under various operating conditions. We designed and implemented the job scheduling simulator for HPC demand-response resource provisioning using a general-purpose discrete-event simulator. Our experiments show that the job scheduling simulator can properly represent the demand response resource provisioning using different job scheduling scenarios