Defect Modes in One-Dimensional Granular Crystals

We study the vibrational spectra of one-dimensional statically compressed granular crystals (arrays of elastic particles in contact) containing defects. We focus on the prototypical settings of one or two spherical defects (particles of smaller radii) interspersed in a chain of larger uniform spherical particles. We measure the near-linear frequency spectrum within the spatial vicinity of the defects, and identify the frequencies of the localized defect modes. We compare the experimentally determined frequencies with those obtained by numerical eigen-analysis and by analytical expressions based on few-site considerations. We also present a brief numerical and experimental example of the nonlinear generalization of a single-defect localized mode

Molecular Mechanism Involved in the Pathogenesis of Early-Onset Epileptic Encephalopathy

Recent studies have shown that neurologic inflammation may both precipitate and sustain seizures, suggesting that inflammation may be involved not only in epileptogenesis but also in determining the drug-resistant profile. Extensive literature data during these last years have identified a number of inflammatory markers involved in these processes of "neuroimmunoinflammation" in epilepsy, with key roles for pro-inflammatory cytokines such as: IL-6, IL-17 and IL-17 Receptor (IL-17R) axis, Tumor-Necrosis-Factor Alpha (TNF-α) and Transforming-Growth-Factor Beta (TGF-β), all responsible for the induction of processes of blood-brain barrier (BBB) disruption and inflammation of the Central Nervous System (CNS) itself. Nevertheless, many of these inflammatory biomarkers have also been implicated in the pathophysiologic process of other neurological diseases. Future studies will be needed to identify the disease-specific biomarkers in order to distinguish epilepsies from other neurological diseases, as well as recognize different epileptic semiology. In this context, biological markers of BBB disruption, as well as those reflecting its integrity, can be useful tools to determine the pathological process of a variety of neurological diseases. However; how these molecules may help in the diagnosis and prognostication of epileptic disorders remains yet to be determined. Herein, authors present an extensive literature review on the involvement of both, systemic and neuronal immune systems, in the early onset of epileptic encephalopathy

Atomic entanglement sudden death in a strongly driven cavity QED system

We study the entanglement dynamics of strongly driven atoms off-resonantly coupled with cavity fields. We consider conditions characterized not only by the atom-field coupling but also by the atom-field detuning. By studying two different models within the framework of cavity QED, we show that the so-called atomic entanglement sudden death (ESD) always occurs if the atom-field coupling lager than the atom-field detuning, and is independent of the type of initial atomic state

No anomalous scaling in electrostatic calibrations for Casimir force measurements

In a recent paper (Phys.Rev.A78, 020101(R) (2008)), Kim at al. have reported a large anomaly in the scaling law of the electrostatic interaction between a sphere and a plate, which was observed during the calibration of their Casimir force set-up. Here we experimentally demonstrate that in proper electrostatic calibrations the scaling law follows the behavior expected from elementary electrostatic arguments, even when the electrostatic voltage that one must apply to minimize the force (typically ascribed to contact potentials) depends on the separation between the surfaces.Comment: Final versio

Comment on ``Solution of Classical Stochastic One-Dimensional Many-Body Systems''

In a recent Letter, Bares and Mobilia proposed the method to find solutions of the stochastic evolution operator $H=H_0 + {\gamma\over L} H_1$ with a non-trivial quartic term $H_1$. They claim, ``Because of the conservation of probability, an analog of the Wick theorem applies and all multipoint correlation functions can be computed.'' Using the Wick theorem, they expressed the density correlation functions as solutions of a closed set of integro-differential equations. In this Comment, however, we show that applicability of Wick theorem is restricted to the case $\gamma = 0$ only.Comment: 1 page, revtex style, comment on paper Phys. Rev. Lett. {\bf 83}, 5214 (1999

Magneto-Optical Stern-Gerlach Effect in Atomic Ensemble

We study the birefringence of the quantized polarized light in a magneto-optically manipulated atomic ensemble as a generalized Stern-Gerlach Effect of light. To explain this engineered birefringence microscopically, we derive an effective Shr\"odinger equation for the spatial motion of two orthogonally polarized components, which behave as a spin with an effective magnetic moment leading to a Stern-Gerlach split in an nonuniform magnetic field. We show that electromagnetic induced transparency (EIT) mechanism can enhance the magneto-optical Stern-Gerlach effect of light in the presence of a control field with a transverse spatial profile and a inhomogeneous magnetic field.Comment: 7 pages, 5 figure

Quantum Speed Limit for Perfect State Transfer in One Dimension

The basic idea of spin chain engineering for perfect quantum state transfer (QST) is to find a set of coupling constants in the Hamiltonian, such that a particular state initially encoded on one site will evolve freely to the opposite site without any dynamical controls. The minimal possible evolution time represents a speed limit for QST. We prove that the optimal solution is the one simulating the precession of a spin in a static magnetic field. We also argue that, at least for solid-state systems where interactions are local, it is more realistic to characterize the computation power by the couplings than the initial energy.Comment: 5 pages, no figure; improved versio

Development and improvement of artificial diets for larvae of Diabrotica species using multidimensional design space techniques

The western corn rootworm (Coleoptera: Chrysomelidae; Diabrotica virgifera virgifera LeConte) and the northern corn rootworm (Coleoptera: Chrysomelidae; Diabrotica barberi Smith & Lawrence) are highly adaptive insect pests and have developed resistance to most possible management tactics in some regions. Transgenic maize hybrids, the latest control tools, which express insecticidal crystalline toxins from Bacillus thuringiensis (Bt) Berliner, have also faltered due to physiological adaptation of western corn rootworm populations. The United States Environmental Protection Agency has mandated insect resistance management plans for corn rootworms that have been directed toward monitoring the development of resistance to each of the Bt toxins. Toxicity bioassays using artificial diet have proven to be valuable for monitoring resistance to Bt toxins in corn rootworm populations. Currently, several proprietary diet formulations for western corn rootworm larvae that have been developed by each of the maize seed companies are used by industry and public researchers in toxicity bioassays to detect decreases in susceptibility of western corn rootworm populations to Bt proteins. No artificial diet has been developed specifically for northern corn rootworm larvae. Since differences in diet formulations can lead to different results in diet toxicity assays, it is impossible to make diet comparisons between toxicity assays using different artificial diets from individual companies and it may not be possible to determine an accurate picture of the test population's phenotype as it relates to Bt resistance. We report new diet formulations that support improved weight gain, larval development, and survival compared with current diets used in western corn rootworm and northern corn rootworm bioassays. The new formulations were created by using response surface modeling coupled with n-dimensional mixture designs to identify and optimize key ingredients based on integrated evaluation of several life history parameters (i.e., weight, molting, survival) while limiting contamination. The new rootworm formulations supported approximately 97% larval survival and molting and increased larval weight gain after 10 days of feedings compared to other diets used in western corn rootworm and northern corn rootworm bioassays rearing. These new formulations provide a standardized growth medium for western corn rootworm and northern corn rootworm larvae that will facilitate toxicity test comparisons conducted by different working groups and meets all regulatory requirements. We developed an improved diet formulation (WCRMO-1) for western corn rootworm (Chapter 2), which was the optimization of diet ingredients in the only published diet for western corn rootworm larvae. This formulation was also compatible for use with all current Bt proteins targeting western corn rootworm larvae. However, this formulation contains corn root powder, which is not available for purchase, limiting the practical use of the diets. We demonstrated that essential growth factors in corn roots that assist in western corn rootworm growth can be extracted suggesting substituting corn root powder with compounds identified from the extract may be possible (Chapter 3). An improved and accessible diet for western corn rootworm (WCRMO-2) that is comparable with all current diets for western corn rootworm larvae and without corn root powder was created by exploring and characterizing protein ingredients from plant, animal and yeast products (Chapter 4). Lastly, we developed the first artificial diet (NCRMO-1) for northern corn rootworm (Chapter 5) comprised of available ingredients that supports performance of northern corn rootworm larvae better than that of publicly available rootworm formulations.Includes bibliographical reference

Interplay between antiferromagnetic order and spin polarization in ferromagnetic metal/electron-doped cuprate superconductor junctions

Recently we proposed a theory of point-contact spectroscopy and argued that the splitting of zero-bias conductance peak (ZBCP) in electron-doped cuprate superconductor point-contact spectroscopy is due to the coexistence of antiferromagnetic (AF) and d-wave superconducting orders [Phys. Rev. B {\bf 76}, 220504(R) (2007)]. Here we extend the theory to study the tunneling in the ferromagnetic metal/electron-doped cuprate superconductor (FM/EDSC) junctions. In addition to the AF order, the effects of spin polarization, Fermi-wave vector mismatch (FWM) between the FM and EDSC regions, and effective barrier are investigated. It is shown that there exits midgap surface state (MSS) contribution to the conductance to which Andreev reflections are largely modified due to the interplay between the exchange field of ferromagnetic metal and the AF order in EDSC. Low-energy anomalous conductance enhancement can occur which could further test the existence of AF order in EDSC. Finally, we propose a more accurate formula in determining the spin polarization value in combination with the point-contact conductance data.Comment: 9 pages, 8 figure