On the Dichotomy between the Nodal and Antinodal Excitations in High-temperature Superconductors

Angle-resolved photoemission data on optimally- and under-doped high temperature superconductors reveal a dichotomy between the nodal and antinodal electronic excitations. In this paper we propose an explanation of this unusual phenomenon by employing the coupling between the quasiparticle and the commensurate/incommensurate magnetic excitations.Comment: 11 pages, 9 figure

Nonlinearity-assisted quantum tunneling in a matter-wave interferometer

We investigate the {\em nonlinearity-assisted quantum tunneling} and formation of nonlinear collective excitations in a matter-wave interferometer, which is realised by the adiabatic transformation of a double-well potential into a single-well harmonic trap. In contrast to the linear quantum tunneling induced by the crossing (or avoided crossing) of neighbouring energy levels, the quantum tunneling between different nonlinear eigenstates is assisted by the nonlinear mean-field interaction. When the barrier between the wells decreases, the mean-field interaction aids quantum tunneling between the ground and excited nonlinear eigenstates. The resulting {\em non-adiabatic evolution} depends on the input states. The tunneling process leads to the generation of dark solitons, and the number of the generated dark solitons is highly sensitive to the matter-wave nonlinearity. The results of the numerical simulations of the matter-wave dynamics are successfully interpreted with a coupled-mode theory for multiple nonlinear eigenstates.Comment: 11 pages, 6 figures, accept for publication in J. Phys.

Simulating Gyrokinetic Microinstabilities in Stellarator Geometry with GS2

The nonlinear gyrokinetic code GS2 has been extended to treat non-axisymmetric stellarator geometry. Electromagnetic perturbations and multiple trapped particle regions are allowed. Here, linear, collisionless, electrostatic simulations of the quasi-axisymmetric, three-field period National Compact Stellarator Experiment (NCSX) design QAS3-C82 have been successfully benchmarked against the eigenvalue code FULL. Quantitatively, the linear stability calculations of GS2 and FULL agree to within ~10%.Comment: Submitted to Physics of Plasmas. 9 pages, 14 figure

The cost-effectiveness of lamotrigine in the maintenance treatment of adults with bipolar I disorder.

OBJECTIVE: To present an economic model and cost-effectiveness estimates for lamotrigine in maintenance treatment of bipolar I disorder (BD-I) using outcomes from the pivotal lamotrigine trials. The main comparator treatments in the pivotal trials were lithium and .no maintenance. (acute-only) treatment. A comparison with olanzapine was included as an indirect analysis following publication of data during the course of our research. METHODS: A Markov model was built around the 3 health states of euthymia, mania, and depression. The base-case model simulates a cohort of 1,000 patients with BD-I who have recently stabilized after resolution of a bipolar mania episode. The cohort was modeled for a period of 18 months. Resource-use estimates were derived from best available published data, treatment guidelines, a physician survey, and published unit cost data. Outputs were measured in terms of costs per acute mood episode avoided, costs per euthymic day gained, and costs per quality-adjusted life-years (QALYs). Direct health care payer costs are used in the analyses. RESULTS: The base-case model for patients with a recent manic episode indicated that lamotrigine is the most effective treatment for avoiding both acute depression episodes and all types of acute episodes (depression and mania). It is also the most effective treatment in terms of number of euthymic days achieved (309 days per patient per year). Olanzapine is most effective for avoiding acute mania episodes. Total direct costs of treatment are lowest for the lithium treatment arm (Dollars 8,710 per patient for the 18-month period). All maintenance therapies were cost effective compared with the no-maintenance (acute-only treatment) arm. In the base case, lamotrigine had incremental cost-effectiveness ratios of Dollars 30 per euthymic day and Dollars 2,400 per acute episode avoided compared with lithium. A QALY analysis indicated that lamotrigine is cost effective in patients with a recent manic episode at Dollars 26,000 per QALY. The base-case model indicated that lamotrigine dominates olanzapine, (that is, lamotrigine costs less and is more effective than olanzapine) in patients with a recent manic episode. In a sensitivity analysis using outcomes from the pivotal trial of recently depressed patients, lamotrigine, in comparison with lithium, was not shown to be as cost effective as in the recently manic patients, but it was still cost effective compared with no maintenance treatment. CONCLUSIONS: For a defined cohort of patients with BD-I, the pharmacoeconomic model indicated that prevention of mood episodes with lithium and lamotrigine is cost effective in patients with a recent manic, mixed, or hypomanic episode. The conclusions with respect to the indirect comparison with olanzapine should be validated if and when direct trial data become available. Cost-effectiveness of maintenance treatments for patients with BD-I (recently depressed as well as recently manic) are likely to improve in models with a broader costing perspective and that take a longer time frame. Further research into the outcome implications of health-related quality of life and other BD subgroups are recommended

Particle-Hole Asymmetry in Doped Mott Insulators: Implications for Tunneling and Photoemission Spectroscopies

In a system with strong local repulsive interactions it should be more difficult to add an electron than to extract one. We make this idea precise by deriving various exact sum rules for the one-particle spectral function independent of the details of the Hamiltonian describing the system and of the nature of the ground state. We extend these results using a variational ansatz for the superconducting ground state and low lying excitations. Our results shed light on the striking asymmetry in the tunneling spectra of high Tc superconductors and should also be useful in estimating the local doping variations in inhomogeneous materials.Comment: 4 pages, no figure

Search for Spin-Dependent Short-Range Force Using Optically Polarized 3^3He Gas

We propose a new method to detect short-range \textit{P-} and \textit{T-} violating interactions between nucleons, based on measuring the precession frequency shift of polarized $^3$He nuclei in the presence of an unpolarized mass. To maximize the sensitivity, a high-pressure $^3$He cell with thin glass windows (250 $\rm\mu m$) is used to minimize the distance between the mass and $^3$He. The magnetic field fluctuation is suppressed by using the $^3$He gas in a different region of the cell as a magnetometer. Systematic uncertainties from the magnetic properties of the mass are suppressed by flipping both the magnetic field and spin directions. Without any magnetic shielding, our result has already reached the sensitivity of the current best limit. With improvement in uniformity and stability of the field, we can further improve the sensitivity by two orders of magnitude over the force range from $10^{-4}-10^{-2}$ m

The swap operation in the two-qubit Heisenberg XXZ model-effects of anisotropy and magnetic field

In this paper we study the swap operation in a two-qubit anisotropic XXZ model in the presence of an inhomogeneous magnetic field. We establish the range of anisotropic parameter within which the swap operation is feasible. The swap errors caused by the inhomogeneous field are evaluated

ZIKV infection activates the IRE1-XBP1 and ATF6 pathways of unfolded protein response in neural cells.

BACKGROUND: Many viruses depend on the extensive membranous network of the endoplasmic reticulum (ER) for their translation, replication, and packaging. Certain membrane modifications of the ER can be a trigger for ER stress, as well as the accumulation of viral protein in the ER by viral infection. Then, unfolded protein response (UPR) is activated to alleviate the stress. Zika virus (ZIKV) is a mosquito-borne flavivirus and its infection causes microcephaly in newborns and serious neurological complications in adults. Here, we investigated ER stress and the regulating model of UPR in ZIKV-infected neural cells in vitro and in vivo. METHODS: Mice deficient in type I and II IFN receptors were infected with ZIKV via intraperitoneal injection and the nervous tissues of the mice were assayed at 5 days post-infection. The expression of phospho-IRE1, XBP1, and ATF6 which were the key markers of ER stress were analyzed by immunohistochemistry assay in vivo. Additionally, the nuclear localization of XBP1s and ATF6n were analyzed by immunohistofluorescence. Furthermore, two representative neural cells, neuroblastoma cell line (SK-N-SH) and astrocytoma cell line (CCF-STTG1), were selected to verify the ER stress in vitro. The expression of BIP, phospho-elF2α, phospho-IRE1, and ATF6 were analyzed through western blot and the nuclear localization of XBP1s was performed by confocal immunofluorescence microscopy. RT-qPCR was also used to quantify the mRNA level of the UPR downstream genes in vitro and in vivo. RESULTS: ZIKV infection significantly upregulated the expression of ER stress markers in vitro and in vivo. Phospho-IRE1 and XBP1 expression significantly increased in the cerebellum and mesocephalon, while ATF6 expression significantly increased in the mesocephalon. ATF6n and XBP1s were translocated into the cell nucleus. The levels of BIP, ATF6, phospho-elf2α, and spliced xbp1 also significantly increased in vitro. Furthermore, the downstream genes of UPR were detected to investigate the regulating model of the UPR during ZIKV infection in vitro and in vivo. The transcriptional levels of atf4, gadd34, chop, and edem-1 in vivo and that of gadd34 and chop in vitro significantly increased. CONCLUSION: Findings in this study demonstrated that ZIKV infection activates ER stress in neural cells. The results offer clues to further study the mechanism of neuropathogenesis caused by ZIKV infection

Charge Ordered RVB States in the Doped Cuprates

We study charge ordered d-wave resonating valence bond states (dRVB) in the doped cuprates, and estimate the energies of these states in a generalized $t-J$ model by using a renormalized mean field theory. The long range Coulomb potential tends to modulate the charge density in favor of the charge ordered RVB state. The possible relevance to the recently observed $4 \times 4$ checkerboard patterns in tunnelling conductance in high $T_c$ cuprates is discussed.Comment: 4 pages, 4 figures, 3 table