A novel Multi-permittivity Cylindrical Dielectric Resonator Antenna for Wideband Applications

In this paper, a novel multi-permittivity cylindrical dielectric resonator antenna for wideband application is presented. The multi-permittivity cylinder is formed by combining two different permittivity material sectors in such a way that each sector (with constant permittivity) is 90 degree apart. A direct microstrip line coupling terminated with T-stub at the open end is used to excite the multi-permittivity cylindrical dielectric resonator. The angular position of the multi sector dielectric resonator with respect to the longitudinal axis of the microstrip line and length of the additional strip at the open end of the feeding circuit is key parameters for wideband operation of the antenna. By optimizing all parameters of the proposed antenna, wideband impedance bandwidth of 56% (12.1 GHz - 21.65 GHz) is achieved. The average gain of the antenna throughout the bandwidth is 5.9 dB with good radiation properties in both E-plane and H-plane. A well matched simulation and experimental results show that the antenna is suitable for wideband applications

A Ka-Band Horn Antenna Excited With Parasitic Dielectric Resonator Antenna

A pyramidal horn antenna excited with parasitic dielectric resonator (DR) antenna for use at Ka-band frequencies is proposed

Development of a Compact Wide-Slot Antenna for Early Stage Breast Cancer Detection Featuring Circular Array Full-View Geometry

A novel planar type antenna printed on a high permittivity Rogers’ substrate is proposed for early stage microwave breast cancer detection. The design is based on a p-shaped wide-slot structure with 50Ω microstrip feeding circuit to eliminate losses of transmission.The design parameters are optimized resulting in a good reflection coefficient at −10 dB from4.5 to 10.9GHz. Imaging result using inhomogeneous breast phantom indicates that the proposed antenna is capable of detecting a 5mm size cancerous tumor embedded inside the fibroglandular region with dielectric contrast between the target and the surroundingmaterials ranging from 1.7:1 to 3.6:1

Nephroprotective Effect of Garlic Chives (Allium Tuberosum) on Bun and Creatinine Levels of Wistar Rats Induced by Doxorubicin

Cancer is the most leading disease that cause of death. Doxorubicin chemotherapy is often used in cancer treatment, because of its effectiveness. Although doxorubicin has a positive effect for killing cancer cell, doxorubicin has many side effects, one of which doxorubicin can cause kidney damage through the process of interstitial fibrosis. Utilization garlic chives extract as co chemotherapy to reduce renal damage induced by doxorubicin is a prospective opportunities. This study aimed to analyze the effect of garlic chives extract as a nephroprotective on levels of BUN and creatinine of wistar rats induced by doxorubicin. The research method was quasi experimental design with post test only randomized controlled group. The results showed that extracts of garlic chives can reduce levels of BUN and creatinine (p <0.05) in the group that only induced by doxorubicin. In conclusion, extract of garlic chives has nephroprotecive effects on wistar rats which were induced by doxorubicin

3D multi-agent models for protein release from PLGA spherical particles with complex inner morphologies

In order to better understand and predict the release of proteins from bioerodible micro- or nanospheres, it is important to know the influences of different initial factors on the release mechanisms. Often though it is difficult to assess what exactly is at the origin of a certain dissolution profile. We propose here a new class of fine-grained multi-agent models built to incorporate increasing complexity, permitting the exploration of the role of different parameters, especially that of the internal morphology of the spheres, in the exhibited release profile. This approach, based on Monte-Carlo (MC) and Cellular Automata (CA) techniques, has permitted the testing of various assumptions and hypotheses about several experimental systems of nanospheres encapsulating proteins. Results have confirmed that this modelling approach has increased the resolution over the complexity involved, opening promising perspectives for future developments, especially complementing in vitro experimentation

Investigation of CuIn1-xGaxSe2 thin films co-evaporated from two metal sources for photovoltaic solar cells

 CuIn1-xGaxSe2 (CIGS) thin films were grown by co-evaporation using two sources for the metal elements (Cu, Ga and In). A Mo coated soda lime glass substrates heated at 500 °C was used for the deposition. X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirm that these films are polycrystalline with a chalcopyrite structure and showed homogeneous grain size estimate about 25 nm. X-ray photoelectron spectroscopy (XPS) was performed to analyse the binding energy values of Ga3d and O1s onto CIGSe layers. The conductivity measurements in the temperature range of 40-400 K were carried out for 0.05≤ x ≤ 0.23. The effect of grain boundary scattering on the electrical transport played an important role in describing the transport processes in these films. The bowing factor is discussed taking into account the deposition techniques of CIGS films. It has been noticed that the open circuit voltage (Voc) is influenced by Ga content and the energy gap value of the absorber CIGS thin layers and yielded a poor efficiency of solar cells

A mild and efficient method for the preparation of 3-(2'-Aminoaryl)pyrazoles from 4-chloroquinolines

We describe a mild and efficient method for the formation of 3-(2'-aminoaryl)pyrazoles in excellent yields from reactions of 4-chloroquinolines with hydrazine. These heterocyclic ring opening reactions occur under much milder conditions then previously described

Spectrum of elementary and collective excitations in the dimerized S=1/2 Heisenberg chain with frustration

We have studied the low-energy excitation spectrum of a dimerized and frustrated antiferromagnetic Heisenberg chain. We use an analytic approach, based on a description of the excitations as triplets above a strong-coupling singlet ground state. The quasiparticle spectrum is calculated by treating the excitations as a dilute Bose gas with infinite on-site repulsion. Additional singlet (S=0) and triplet (S=1) modes are found as two-particle bound states of the elementary triplets. We have also calculated the contributions of the elementary and collective excitations into the spin structure factor. Our results are in excellent agreement with exact diagonalizations and dimer series expansions data as long as the dimerization parameter $\delta$ is not too small ($\delta>0.1$), i.e. while the elementary triplets can be treated as localized objects.Comment: 18 pages, 13 figure

Histopathological and cholinesterase changes in the gills of Clarias gariepinus as a result of cadmium exposure

Aim : The cholinesterase (ChE) based inhibition and histopathological studies from fish were investigated and represented in this study to develop as one of the great potential biomarkers for heavy metals monitoring. Methodology : In this study, the histopathological study of gills were observed a under microscope. The capability of ChE extracted from the gills of Clarias gariepinus was assessed for declining Cd. ChE was purified through affinity chromatography and continued with the optimisation and inhibition study (IC50) of cholinesterase. Results : Histopathological study of gills was carried out and several changes such as aneurysm, necrosis and lamella fusion were noted. Purification fold obtained from purified enzyme was 1.15 with 30% a yield specific activity 20.726. The optimum temperature for purified AChE was 35°C along with acetylthiocholine iodide (ATC) as a preferable substrate that had the highest Vmax value of 0.5452 U mg'1 and the lowest Km value of 0.0311 mM. The optimum pH was observed to be 10 of Tris-HCl as a medium. Meanwhile, the IC50 of cadmium was 6.808 mg ľ with R2 value of 0.9532. Interpretation : The result of the study can be used as a tool for further developing a biomarker for the detection of heavy metals in aquatic ecosystems. In addition, the baseline data provided can also be used for designing a kit, which would give rapid and accurate result