Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Response of arbuscular mycorrhizal mungbean plants to ambient air pollution

The experiments were conducted in open top chamber system installed at the University of the Punjab, Quaid-e-Azam Campus, Lahore, Pakistan. The mungbean ( Vigna radiata (L.) Wilczek var.M28) seeds were sown in earthen pots and were kept in filtered air, unfiltered air and ambient air. The ozone concentration was monitored daily during 1000hrs till 1600 h. The data for light intensity and relative humidity was also regularly collected. The sets of plants growing in FA chambers (without ozone and dust particles) responded well as regards growth and yields are concerned. Unfiltered air reduced the number of nodules, their biomass and nitroginase activity in mungbean plants. The present study documents that the species of mycorrhizal fungi sensitive to tropospheric ozone failed to reproduce in ambient air and unfiltered air chambers (without dust particles). Out of a total of 24 species, eighteen species belonged to the genus Glomus, two each to Sclerocystis, to Acaulospora and one each to Gigaspora and Scutellospora. The total number of species was variable during the growth phase. The total number of species reduced in soil of UFA chambers with the passage of time. Species richness reduced to almost half in UFA plants as compared to FA plants. Species of the Genus Glomus were highly abundant species at various harvests in all air treatments. Amongst most abundantly recovered Glomus species were G. fasciculatum, G. mosseae, G. aggregatum, G. caledonicum, G. deserticola, G. geosporum, and G. monosporum. The pattern of abundance kept on varying at various harvests for different air and mycorrhizal treatments. In the case of plants of UFA treatment, only two species of Glomus were abundant namely G. fasciculatum and G. geosporum. Species of Acaulospora and Gigaspora in particular and Scutellospora and Sclerocystis in general were sensitive to polluted air