The Struggle for Federal Food and Drugs Legislation

In this paper we evaluate the application of convex optimization for PAPR reduction on OFDM 802.11a signal type. A radio frequency power amplifier is measured and characterized while excited by both original and optimized OFDM signals. A state-of-art test setup was used for the purpose. Figure of merits such as power added efficiency, in-band errors, and out-of-band spectral emissions are investigated for their relevance and a study of the power distribution in the excitation signal is evaluated.©2010 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEEKK

Radar Scattering from a Diffuse Vegetation Layer over a Smooth Surface

A simple model is presented for the oblique backscatter and bistatic scatter from a smooth surface overlain by a diffuse layer. Only single scattering in the diffuse layer is taken into account. The model analysis shows that the combination of volume scattering and oblique reflection at the surface may increase appreciably the waves scattering. The scattering strongly depends on the properties of the smooth surface. These results support some of the observations made with the Seasat spaceborne imaging radar over flooded regions with heavy vegetation cover

Radiation Characteristics of a Source in a Thin Substrate Mounted Over a Dielectric Medium

The radiation pattern of a line source is calculated for the case where the source is lying on the top or the bottom surface of a lossless dielectric substrate that is mounted on the top of a semi-infinite dielectric medium. It is found that in both cases the pattern along interfaces has a null; that the pattern in the upper semi-infinite medium has a single lobe; and that the pattern in the lower semi-infinite medium has many lobes, the number of which varies with the substrate thickness. It is shown that in both cases the power radiated into the lower medium is more than that radiated into the upper medium. Applications of this calculation in remote sensing, microstrip antenna technology, and antenna arrays are discussed

Electromagnetic wave propagation in the wire medium: a complex medium with long thin inclusions

The wire medium is a type of complex artificial material we conceptually envision as many identical finite-length, parallel, thin wire inclusions embedded within a host medium. It is representative of a class of novel artificial materials characterized by long thin inclusions. Unlike some conventional artificial material, the inclusions of this class are not necessarily electrically short. Here, we present our theoretical analysis for wire media and by studying certain salient features of plane-wave propagation through these media, introduce equivalent medium parameters that depend, among other parameters, on the direction of wave propagation. The approach we use separates the artificial material into its elementary planes and then uses periodic moment method techniques to individually characterize each elementary plane. Analytic formulas from periodic structure theory are then used to determine the effective wavenumber for the overall medium and the transverse impedance at the midpoint between adjacent elementary planes. Our examples show that some realizations of these media are spatially dispersive and may exhibit interesting features such as angular windows of propagation and other properties that are dependent on the polarization, frequency and direction of wave propagation

An Idea for Electromagnetic Feedforward-Feedbackward Media

In this paper, an idea for a new class of complex media that we name feedforward–feedbackward (FFFB) media is presented and some of the results of our theoretical work in analyzing plane wave propagation in the axial direction through these media are described. The concept of FFFB media, as introduced here, was inspired by the theoretical research of Saadoun and Engheta on a variation of artificial chiral media. Like chiral media, to our knowledge there are no naturally occurring FFFB media for the microwave frequency band; for this reason we introduce an idea for artificial FFFB media. The focus of this paper is on one conceptualization of such media, namely dipole–dipole FFFB media. First, we present the calculation of the necessary constitutive parameters for studying axial plane wave propagation. Then we solve the macroscopic Maxwell equations in the k domain for axial plane wave propagation in an unbounded source-free crossed-dipole FFFB medium. Finally, we present the dispersion equation for this medium in this case, discuss some of the physical properties of its roots and certain features of the polarization eigenstates, and briefly speculate some of the potential applications of this medium

On the Near-Zone Inverse Doppler Effect

Attention is invited to the recently discovered inverse Doppler effect which occurs in the near-zone field of an antenna emitting a continuous wave. On approaching the antenna, the received signal is blue-shifted in the far zone and then red-shifted in the near zone; and on receding from the antenna, the received signal is blue-shifted in the near zone and then red-shifted in the far zone. Calculations are presented for the case where the antenna is a simple dipole. It is shown that this effect gives not only the vector velocity of the moving receiver but also its range, i.e., its distance from the antenna

Detection of ApoE E2, E3 and E4 alleles using MALDI-TOF mass spectrometry and the homogeneous mass-extend technology

Apolipoprotein (Apo) E is one of the five main types of blood lipoproteins (A–E). It is synthesized primarily in the liver and brain and helps in transporting lipids from one place to another as well as facilitates the clearing of dietary fats, such as triglycerides, from the blood. The ApoE gene exists in three different forms: E2, E3 and E4. E3 is considered to be the normal form. Variants of the ApoE gene have been associated with various diseases. Developing an assay for the genotyping of ApoE variants for use both in clinical and large cohort based association settings would be extremely valuable and would require the use of a platform that has high-throughput capabilities and is highly accurate. Here we describe an assay for the simultaneous genotyping of the ApoE variants in a single bi-plex reaction and a single well using the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and the homogeneous mass-extend (hME) technology. The assay is robust, highly accurate and suitable for both clinical applications and for the genotyping of large disease cohorts. Moreover, the prevalence of ApoE variants in a cohort of Caucasians from the central Wisconsin area is outlined

Radar Scattering from a Diffuse Vegetation Layer over a Smooth Surface

A simple model is presented for the oblique backscatter and bistatic scatter from a smooth surface overlain by a diffuse layer. Only single scattering in the diffuse layer is taken into account. The model analysis shows that the combination of volume scattering and oblique reflection at the surface may increase appreciably the waves scattering. The scattering strongly depends on the properties of the smooth surface. These results support some of the observations made with the Seasat spaceborne imaging radar over flooded regions with heavy vegetation cover