Selective excitation of homogeneous spectral lines

It is possible, for homogeneously broadened lines, to excite selectively the response signals, which are orders of magnitude narrower than the original lines. The new type of echo, which allows detecting such signals, and the formalism, useful for understanding the phenomenon, as well as the experimental examples from NMR spectroscopy are presented.Comment: 19 pages, 8 figure

Nuclear magnetic resonance implementation of the Deutsch-Jozsa algorithm using different initial states

The Deutsch-Jozsa algorithm distinguishes constant functions from balanced functions with a single evaluation. In the first part of this work, we present simulations of the nuclear magnetic resonance (NMR) application of the Deutsch-Jozsa algorithm to a 3-spin system for all possible balanced functions. Three different kinds of initial states are considered: a thermal state, a pseudopure state, and a pair (difference) of pseudopure states. Then, simulations of several balanced functions and the two constant functions of a 5-spin system are described. Finally, corresponding experimental spectra obtained by using a 16-frequency pulse to create an input equivalent to either a constant function or a balanced function are presented, and the results are compared with those obtained from computer simulations.Comment: accepted for publication in the Journal of Chemical Physic

Role of splenectomy in human liver transplantation under modern-day immunosuppression

Between January 1987 and October 1991, 1466 patients underwent consecutive Orthotopic Liver Transplantation (OLTx) at the University of Pittsburgh. Forty of these patient's had concomitant splenectomy with OLTx. These patients were compared to 147 randomly selected OLTx patients without splenectomy within the same time period. One-year patient and graft survival (PS and GS) were lower in splenectomized (Splx) patients compared to nonsplenectomized (non-Splx) patients (59% vs 86% PS, 55% vs 80% GS, respectively). One-month and one-year patient mortality in the Splx group was higher than in the non-splx patients (20% vs 3.4% P < 0.001 for one month; 40% vs 14.3%, P = 0.003 for one year, respectively). One-month and one-year sepsis-related mortality was also high in Splx patients (17.5% vs 2.7%, P = 0.0022, for one month, and 30% vs 11.5%, P = 0.0043, for one year, respectively). We conclude that concomitant splenectomy with OLTx has a significantly higher patient mortality mainly due to its septic complications and, at present, unless there is a specific indication for a splenectomy, the routine addition of this procedure to liver allograft surgery would not be recommended

Gravitational Waves from Preheating in M-flation

Matrix inflation, or M-flation, is a string theory motivated inflationary model with three scalar field matrices and gauge fields in the adjoint representation of the $\mathbf{U}(N)$ gauge group. One of these $3N^2$ scalars appears as the effective inflaton while the rest of the fields (scalar and gauge fields) can play the role of isocurvature fields during inflation and preheat fields afterwards. There is a region in parameter space and initial field values, "the hilltop region," where predictions of the model are quite compatible with the recent Planck data. We show that in this hilltop region, if the inflaton ends up in the supersymmetric vacuum, the model can have an embedded preheating mechanism. Couplings of the preheat modes are related to the inflaton self-couplings and therefore are known from the CMB data. Through lattice simulations performed using a symplectic integrator, we numerically compute the power spectra of gravitational waves produced during the preheating stage following M-flation. The preliminary numerical simulation of the spectrum from multi-preheat fields peaks in the GHz band with an amplitude $\Omega_{\mathrm{gw}}h^{2} \propto 10^{-16}$, suggesting that the model has concrete predictions for the ultra-high frequency gravity-wave probes. This signature could be used to distinguish the model from rival inflationary modelsComment: v1:27 pages and 7 figures; v2: typos corrected; v3: references added; v4: matched the JCAP versio

Comment on "Resilience of gated avalanche photodiodes against bright illumination attacks in quantum cryptography"

This is a comment on the publication by Yuan et al. [Appl. Phys. Lett. 98, 231104 (2011); arXiv:1106.2675v1 [quant-ph]].Comment: 2 page