Dualities of deformed N = 2 SCFTs from link monodromy on D3-brane states

We study D3-brane theories that are dually described as deformations of two different N= 2 superconformal theories with massless monopoles and dyons. These arise at the self-intersection of a seven-brane in F-theory, which cuts out a link on a small three-sphere surrounding the self-intersection. The spectrum is studied by taking small loops in the three-sphere, yielding a link-induced monodromy action on string junction D3-brane states, and subsequently quotienting by the monodromy. This reduces the differing flavor algebras of the N= 2 theories to the same flavor algebra, as required by duality, and projects out charged states, yielding an N= 1 superconformal theory on the D3-brane. In one, a deformation of a rank one Argyres-Douglas theory retains its SU(2) flavor symmetry and exhibits a charge neutral flavor triplet that is comprised of electron, dyon, and monopole string junctions. From duality we argue that the monodromy projection should also be imposed away from the conformal point, in which case the D3-brane field theory appears to exhibit confinement of electrons, dyons, and monopoles. We will address the mathematical counterparts in a companion paper

Root Damage by Insects Reverses the Effects of Elevated Atmospheric CO2 on Eucalypt Seedlings

Predicted increases in atmospheric carbon dioxide (CO(2)) are widely anticipated to increase biomass accumulation by accelerating rates of photosynthesis in many plant taxa. Little, however, is known about how soil-borne plant antagonists might modify the effects of elevated CO(2) (eCO(2)), with root-feeding insects being particularly understudied. Root damage by insects often reduces rates of photosynthesis by disrupting root function and imposing water deficits. These insects therefore have considerable potential for modifying plant responses to eCO(2). We investigated how root damage by a soil-dwelling insect (Xylotrupes gideon australicus) modified the responses of Eucalyptus globulus to eCO(2). eCO(2) increased plant height when E. globulus were 14 weeks old and continued to do so at an accelerated rate compared to those grown at ambient CO(2) (aCO(2)). Plants exposed to root-damaging insects showed a rapid decline in growth rates thereafter. In eCO(2), shoot and root biomass increased by 46 and 35%, respectively, in insect-free plants but these effects were arrested when soil-dwelling insects were present so that plants were the same size as those grown at aCO(2). Specific leaf mass increased by 29% under eCO(2), but at eCO(2) root damage caused it to decline by 16%, similar to values seen in plants at aCO(2) without root damage. Leaf C:N ratio increased by >30% at eCO(2) as a consequence of declining leaf N concentrations, but this change was also moderated by soil insects. Soil insects also reduced leaf water content by 9% at eCO(2), which potentially arose through impaired water uptake by the roots. We hypothesise that this may have impaired photosynthetic activity to the extent that observed plant responses to eCO(2) no longer occurred. In conclusion, soil-dwelling insects could modify plant responses to eCO(2) predicted by climate change plant growth models