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Coherent transport in a ferromagnetic semiconductor (FS)/d-wave superconductor (SC)/FS structure with {110} interfaces is studied by extending Bogoliubov-de Gennes equation into eight components, in which the interband coupling of heavy and light hole bands in the FS, the strengths of potential scattering at the interfaces, and the mismatches in the effective mass and Fermi vector between the FS and SC are taken into account. Twofold Andreev reflections exist due to the existence of two bands in the FS, in which the incident hole and the two Andreev-reflected electrons, belonging to the different spin subbands, form twofold spin-singlet pairing states near the FS/SC interface. It is shown that due to the interplay of the SC with unconventional d-wave pairing symmetry and FS, the differential conductance and tunneling magnetoresistance exhibit an abundant dependence on not only the interband coupling in the FS but also the strengths of potential scattering at the interfaces. More importantly, the properties are found to be quite different from those in the FS/s-wave SC/FS structure with conventional pairing symmetry for the SC. [ABSTRACT FROM AUTHOR]

Despite the recognition that cortical thickness is heritable and correlates with intellectual ability in children and adolescents, the genes contributing to individual differences in these traits remain unknown. We conducted a large-scale association study in 1583 adolescents to identify genes affecting cortical thickness. Single-nucleotide polymorphisms (SNPs; n = 54 837) within genes whose expression changed between stages of growth and differentiation of a human neural stem cell line were selected for association analyses with average cortical thickness. We identified a variant, rs7171755, associating with thinner cortex in the left hemisphere (P= 1.12x10-7), particularly in the frontal and temporal lobes. Localized effects of this SNP on cortical thickness differently affected verbal and nonverbal intellectual abilities. The rs7171755 polymorphism acted in c/s to affect expression in the human brain of the synaptic cell adhesion glycoprotein-encoding gene NPTN. We also found that cortical thickness and NPTN expression were on average higher in the right hemisphere, suggesting that asymmetric NPTN expression may render the left hemisphere more sensitive to the effects of NPTN mutations, accounting for the lateralized effect of rs7171755 found in our study. Altogether, our findings support a potential role for regional synaptic dysfunctions in forms of intellectual deficits. [ABSTRACT FROM AUTHOR]

Abstract??A new design approach of a parallel distributed fuzzy sliding mode controller for nonlinear systems with mismatched time varying uncertainties is presented in this paper. The nonlinear system is approximated by the Takagi?Sugeno fuzzy linear model. The approximation error between the nonlinear system and the fuzzy linear model is considered as one part of the uncertainty in the uncertain nonlinear system. The time varying uncertainties are assumed to have the format which enables the design of the coefficient matrix of the sliding function to satisfy a sliding coefficient matching condition. With the sliding coefficient matching condition satisfied, a parallel distributed fuzzy sliding mode controller (PDFSC) is designed. The stability and the sliding mode of the fuzzy sliding control system are guaranteed. Also, the nonlinear system is shown to be invariant on the sliding surface. Moreover, the chattering around the sliding surface in the sliding mode control can be reduced by the proposed design approach. Simulation results are included to illustrate the effectiveness of the proposed fuzzy sliding mode controller. [ABSTRACT FROM AUTHOR]

We theoretically investigate the supercurrent through a Josephson junction with at least one superconducting electrode directly coupled to a valley-polarized graphene sheet. The anomalous Josephson effect is shown and remarkably manipulated by interface valley-polarized mixing together with combination of the static staggered potentials and off-resonant circularly polarized light field inducing the valley polarization. The unconventional Josephson effect results from the breaking of underlying chiral (polarized-valley rotational) and time-reversal symmetries, which in turn shows the equivalence of the valley and spin freedoms. The valley-polarized interface-tunable phase offset will be of great interest in the designing and fabrication of such novel devices based on valleytronics as superconducting flux- and phase-based quantum bits, phase batteries and rectifiers. [ABSTRACT FROM AUTHOR]

An extended four-component Bogoliubov–de Gennes equation is applied to study the Josephson effect in ballistic limit between either two iron-based superconductors (SCs) or an iron-based SC and a conventional s-wave SC, separated by a normal metal. A 0–π transition as a function of interband coupling strength α is always exhibited, arising from the tuning of mixing between the two trajectories with opposite phases. The novel property can be experimentally used to discriminate the -wave pairing symmetry in the iron-based SCs from the -wave one in MgB2. The effect of interface transparency on the 0–π transition is also presented. The 0–π transition as a function of α is wholly distinct from that as a function of barrier strength or temperature in recent theories (Linder et al 2009 Phys. Rev. B 80 020503(R)). The possible experimental probe of the phase-shift effect in iron-based SC Josephson junctions is commented on as well. [ABSTRACT FROM AUTHOR]