A Metamaterial Backed Dipole Antenna for High Gain Directional Communications

The enhanced radiation performance of a dipole antenna backed by the split ring resonator-continuous wire pair array working in the H┴ excitation scenario is presented in this paper.  The H┴ excitation scenario of the metamaterial is used to get zero reflection phase resulting in enhanced gain performance. The two layer meta-structure along with the dipole is fabricated on a low cost substrate of dielectric constant 4.4 and height 1mm. The reflection properties of the metamaterial structure and its effect on the radiation performance of the dipole antenna are presented in this paper

A Metamaterial Backed Dipole Antenna for High Gain Directional Communications

The enhanced radiation performance of a dipole antenna backed by the split ring resonator-continuous wire pair array working in the H┴ excitation scenario is presented in this paper.  The H┴ excitation scenario of the metamaterial is used to get zero reflection phase resulting in enhanced gain performance. The two layer meta-structure along with the dipole is fabricated on a low cost substrate of dielectric constant 4.4 and height 1mm. The reflection properties of the metamaterial structure and its effect on the radiation performance of the dipole antenna are presented in this paper

Grating-based Dipole Antenna Configuration for High Gain Directional Radiation characteristics

The experimental and simulation studies of the radiation performance enhancement of a dipole antenna using metal strip grating are presented in this paper. The subwavelength imaging configuration of the metal strip grating is utilized for enhancing the radiation performance of a dipole antenna working in the S-band. The resultant design shows a gain of 9 dBi and front to back ratio of the design is found to be -23 dB at resonance. The coupling between electric and magnetic resonances provides the necessary impedance matching performance when the antenna is brought in the vicinity of the grating

The Development of Chemically Vapor Deposited Mullite Coatings for the Corrosion Protection of SiC

Crystalline mullite coatings have been chemically vapor deposited onto SiC substrates to enhance the corrosion and oxidation resistance of the substrate. Current research has been divided into three distinct areas: (1) Development of the deposition processing conditions for increased control over coating`s growth rate, microstructure, and morphology; (2) Analysis of the coating`s crystal structure and stability; (3) The corrosion resistance of the CVD mullite coating on SiC

Grating-based Dipole Antenna Configuration for High Gain Directional Radiation characteristics

The experimental and simulation studies of the radiation performance enhancement of a dipole antenna using metal strip grating are presented in this paper. The subwavelength imaging configuration of the metal strip grating is utilized for enhancing the radiation performance of a dipole antenna working in the S-band. The resultant design shows a gain of 9 dBi and front to back ratio of the design is found to be -23 dB at resonance. The coupling between electric and magnetic resonances provides the necessary impedance matching performance when the antenna is brought in the vicinity of the grating

Silicon Pad Detectors for the PHOBOS Experiment at RHIC

The PHOBOS experiment is well positioned to obtain crucial information about relativistic heavy ion collisions at RHIC, combining a multiplicity counter with a multi-particle spectrometer. The multiplicity arrays will measure the charged particle multiplicity over the full solid angle. The spectrometer will be able to identify particles at mid-rapidity. The experiment is constructed almost exclusively of silicon pad detectors. Detectors of nine different types are configured in the multiplicity and vertex detector (22,000 channels) and two multi-particle spectrometers (120,000 channels). The overall layout of the experiment, testing of the silicon sensors and the performance of the detectors during the engineering run at RHIC in 1999 are discussed.Comment: 7 pages, 7 figures, 1 table, Late

Substantial fat mass loss reduces low-grade inflammation and induces positive alteration in cardiometabolic factors in normal-weight individuals

( )The accumulation of fat, especially in visceral sites, is a significant risk factor for several chronic diseases with altered cardiometabolic homeostasis. We studied how intensive long-term weight loss and subsequent weight regain affect physiological changes, by longitudinally interrogating the lipid metabolism and white blood cell transcriptomic markers in healthy, normal-weight individuals. The current study examined 42 healthy, young (age: 27.5 +/- 4.0 years), normal-weight (body mass index, BMI: 23.4 +/- 1.7 kg/m(2)) female athletes, of which 25 belong to the weight loss and regain group (diet group), and 17 to the control group. Participants were evaluated, and fasting blood samples were drawn at three time points: at baseline (PRE); at the end of the weight loss period (MID: 21.1 +/- 3.1 weeks after PRE); and at the end of the weight regain period (POST: 18.4 +/- 2.9 weeks after MID). Following the weight loss period, the diet group experienced a similar to 73% reduction (similar to 0.69 kg) in visceral fat mass (false discovery rate, FDR <2.0 x 10(-16)), accompanied by anti-atherogenic effects on transcriptomic markers, decreased low-grade inflammation (e.g., as alpha(1)-acid glycoprotein (FDR = 3.08 x 10(-13)) and hs-CRP (FDR = 2.44 x 10(-3))), and an increase in functionally important anti-atherogenic high-density lipoprotein -associated metabolites (FDR <0.05). This occurred even though these values were already at favorable levels in these participants, who follow a fitness-lifestyle compared to age- and BMI-matched females from the general population (n = 58). Following the weight regain period, most of the observed beneficial changes in visceral fat mass, and meta bolomic and transcriptomic profiles dissipated. Overall, the beneficial anti-atherogenic effects of weight loss can be observed even in previously healthy, normal-weight individuals.Peer reviewe

Landau theory applied to phase transitions in calcium orthotungstate and isostructural compounds

The pressure-driven tetragonal-to-monoclinic phase transition in CaWO4 and related scheelite-structured orthotungstates is analysed in terms of spontaneous strains. Based upon our previous high-pressure x-ray diffraction results and the Landau theory, it is suggested that the scheelite-to-fergusonite transition is of second order in nature.Comment: 14 pages, 3 figure