Current rectification by asymmetric molecules: An ab initio study

We study current rectification effect in an asymmetric molecule HOOC-C$_6$H$_4$-(CH$_2$)$_n$ sandwiched between two Aluminum electrodes using an {\sl ab initio} nonequilibrium Green function method. The conductance of the system decreases exponentially with the increasing number $n$ of CH$_2$. The phenomenon of current rectification is observed such that a very small current appears at negative bias and a sharp negative differential resistance at a critical positive bias when $n\ge 2$. The rectification effect arises from the asymmetric structure of the molecule and the molecule-electrode couplings. A significant rectification ratio of $\sim$38 can be achieved when $n=5$.Comment: to appear in J. Chem. Phy

Follow-up observation of three operative treatments for primary infantile glaucoma

AIM: To compare the efficacy and complication of extra-trabeculotomy in combination with trabeculectomy and trabeculectomy and compound trabeculectomy in the treatment of primary infantile glaucoma. <p>METHODS: Patients with primary infantile glaucoma undergone one of the three procedures from Jan 2006 to Jan 2014 were selected. Among them, group A(20 patients, 31 eyes)underwent extra-trabeculotomy in combination with trabeculectomy, group B(20 patients, 32 eyes)underwent trabeculectomy, while group C(20 patients, 30 eyes)underwent compound trabeculectomy <p>RESULTS: The success rates in group A were 96.8% at the time of discharge and 90.3% during follow-up(mean 24mo); the rates in group B were 96.9% and 81.2%(mean 24mo)the rates in group C were 83.3% and 76.7%(mean 24mo)respectively, the differences being significant(<i>P </i><0.05). In group A and group B, there was no severe complications, while in group C, one case had vitreous prolapse.<p>CONCLUSION: Extra-trabeculotomy in combination with trabeculectomy is more efficacious and safer than trabeculectomy and compound trabeculectomy in the treatment of primary infantile glaucoma. It should be the first choice for primary infantile glaucoma

Signature of Pseudo Nambu-Goldstone Higgs boson in its Decay

If the Higgs boson is a pseudo Nambu-Goldstone boson (PNGB), the $hZ\gamma$ contact interaction induced by the $\mathcal{O}(p^4)$ invariants of the non-linear sigma model is free from its nonlinearity effects. The process $h\rightarrow Z\gamma$ can be used to eliminate the universal effects of heavy particles, which can fake the nonlinearity effects of the PNGB Higgs boson in the process $h\rightarrow V^*V$ ($V=W^\pm$,\ $Z$). We demonstrate that the ratio of the signal strength of $h\rightarrow Z\gamma$ and $h\rightarrow V^*V$ is good to distinguish the signature of the PNGB Higgs boson from Higgs coupling deviations

Itinerant quantum critical point with frustration and non-Fermi-liquid

Employing the self-learning quantum Monte Carlo algorithm, we investigate the frustrated transverse-field triangle-lattice Ising model coupled to a Fermi surface. Without fermions, the spin degrees of freedom undergoes a second-order quantum phase transition between paramagnetic and clock-ordered phases. This quantum critical point (QCP) has an emergent U(1) symmetry and thus belongs to the (2+1)D XY universality class. In the presence of fermions, spin fluctuations introduce effective interactions among fermions and distort the bare Fermi surface towards an interacting one with hot spots and Fermi pockets. Near the QCP, non-Fermi-liquid behavior are observed at the hot spots, and the QCP is rendered into a different universality with Hertz-Millis type exponents. The detailed properties of this QCP and possibly related experimental systems are also discussed.Comment: 9 pages, 8 figure