Full embroidery designed electro-textile wearable tag antenna for WBAN application

A flexible and totally wearable textile antenna is proposed by embroidering the conductive threads into garments. A purely polyester substrate has been utilized, which provides a tag that can be easily integrated with the clothes. The proposed tag antenna is small with dimensions of 72 × 20 × 2.75 mm3 and offers an enhanced performance in terms of gain and stability when worn on different body locations. Experimental results demonstrate an improved impedance matching owing to the elasticity of the E-shaped inductive feeder. Close agreement has been achieved between the simulated and measured results

Frequency-reconfigurable millimeter-wave rectangular dielectric resonator antenna

This paper introduces an innovative and cost-effective approach for developing a millimeter-wave (mmWave) frequency-reconfigurable dielectric resonator antenna (DRA), which has not been reported before. The antenna integrates two rectangular DRA elements, where each DRA is centrally fed via a slot. A strategically positioned PIN diode is employed to exert control over performance by modulating the ON–OFF states of the diode, thereby simplifying the design process and reducing losses. In the OFF state, the first DRA, RDRA-I, exclusively supports the TE311 resonance mode at 24.3 GHz, offering a 2.66% impedance bandwidth and achieving a maximum broadside gain of 9.2 dBi. Conversely, in the ON state, RDRA-I and RDRA-II concurrently operate in the TE513 resonance mode at 29.3 GHz, providing a 2.7% impedance bandwidth and yielding a high gain of up to 11.8 dBi. Experimental results substantiate that the proposed antenna presents an attractive solution for applications necessitating frequency-reconfigurable and high-performance mmWave antennas in 5G and Beyond 5G (B5G) communication systems

Coherently coupled photonic-crystal surface-emitting laser array

The realization of a 1 × 2 coherently coupled photonic crystal surface emitting laser array is reported. New routes to power scaling are discussed and the electronic control of coherence is demonstrated

Comparative Study of Wound Healing After Treatment With Crude Date Extract and Silver Sulphadiazine

Crude date extract in comparison with silver sulphadiazine was tested to evaluate their effects on wound healing and their antimicrobial activities against the growth of Staphylococcus aureus. Crude date extract 5% (w/v) and silver sulphadiazine 20% (w/v) inhibited the growth of Staphylococcus aureus by 67% and 87% respectively. However,10% and 20% (w/v) date extract showed 100% inhibition. Date extract was fractionated using different solvents with different polarities; all fractions were tested for their antimicrobial activities. Ethyl acetate fraction was found to have inhibitory activity against the growth of Staphylococcus aureus. Preparative TLC was done for ethyl acetate fraction which was further identified to be terpenoidal compound. The histological changes in healing wounds have also been investigated after treatment with 20% and 40% crude date extract ,and silver sulphadiazine and amoxicillin by light microscopy.  The results obtained from 20% CDE treatment as compared to untreated control indicated that, this treatment promotes the process of wound healing and stimulates fibroblast, collagen and epithelialization significantly. This effect was comparable with the effect of silver sulphadiazine treatment

A Low Profile Switchable Pattern Directivity Antenna Using Circular Sectorized EBG

In this paper, a low profile patch antenna switchable radiation pattern diversity with total thickness of less than λ 0 /14 has been established.. The novel antenna structure is based on a conformal patch antenna operating in TM01 mode is integrated over an electromagnetic band gap (EBG) surface to provide a beam scanning antenna. The circular EBG elements are arranged in 6-sectors and the vias on each sector of the EBG are switched in and out to steer the beam into that sectors. The reflection coefficients for the antenna when the vias are switched remain stable. The simulation and experimentation results have shown that the antenna power pattern directed toward the sector, without via or the middle of sectors, without via. Overall a flexible low profile beam steering antenna is demonstrated. The antenna is designed for wireless network application especially to improve the system performance in multipath propagation environment. Furthermore, the low profile antenna makes it suitable to be used in vehicular applicatio

Microstrip Patch Antenna Array Mutual Coupling Reduction using Capacitive Loaded Miniaturized EBG

In this paper, a compact miniaturized EBG loaded with surface mounting capacitor has been developed. The dimension of the EBG patch with approximately λ/36 has been achieved with dimension highly dependent on the capacitor values. The integration of the capacitive loaded miniaturized EBG with a couple of microstrip patch antenna has reduced approximately 12dB mutual coupling within the elements at the antenna resonance frequency of 2.2GHz. The antenna E-plane gain has been improved for more than 2dB with 3dB reduction in side lobes when comparing the traditional array with the array integrated with EBG. The propagation characteristics and gain of the array have been analyzed using CST Microwave Studio (CST MWS). The measured results have shown good agreement with the simulated results. The miniaturized EBG will be very useful in minimizing the space within the array antenna especially for the MIMO applicatio

Three-dimensional finite-difference time-domain modelling of photonic crystal surface-emitting lasers

We investigate the beam divergence in far-field region, diffraction loss and optical confinement factors of all-semiconductor and void-semiconductor photonic-crystal surface-emitting lasers (PCSELs), containing either InGaP/GaAs or InGaP/air photonic crystals using a three-dimensional FDTD model. We explore the impact of changing the PC hole shape, size, and lattice structure in addition to the choice of all-semiconductor or void-semiconductor designs. We discuss the determination of the threshold gain from the diffraction losses, and explore limitations to direct modulation of the PCSEL. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

On-chip circularly polarized circular loop antennas utilizing 4H-SiC and GaAs substrates in the Q/V band

This paper presents a comprehensive assessment of the performance of on-chip circularly polarized (CP) circular loop antennas that have been designed and fabricated to operate in the Q/V frequency band. The proposed antenna design incorporates two concentric loops, with the outer loop as the active element and the inner loop enhancing the CP bandwidth. The study utilizes gallium arsenide (GaAs) and silicon carbide (4H-SiC) semiconductor wafer substrates. The measured results highlight the successful achievement of impedance matching at 40 GHz and 44 GHz for the 4H-SiC and GaAs substrates, respectively. Furthermore, both cases yield an axial ratio (AR) of less than 3 dB, with variations in bandwidths and frequency bands contingent upon the dielectric constant of the respective substrate material. Moreover, the outcomes confirm that utilizing 4H-SiC substrates results in a significantly higher radiation efficiency of 95%, owing to lower substrate losses. In pursuit of these findings, a 4-element circularly polarized loop array antenna has been fabricated for operation at 40 GHz, employing a 4H-SiC wafer as a low-loss substrate. The results underscore the antenna’s remarkable performance, exemplified by a broadside gain of approximately 9.7 dBic and a total efficiency of circa 92%. A close agreement has been achieved between simulated and measured results

Preclinical systemic toxicity evaluation of chitosan-solid–lipid nanoparticle-encapsulated aspirin and curcumin in combination with free sulforaphane in BALB/c mice

Arvind Thakkar,1 Sushma Chenreddy,1 Astrid Thio,1 Wael Khamas,2 Jeffrey Wang,1 Sunil Prabhu1 1Department of Pharmaceutical Sciences, College of Pharmacy, 2College of Veterinary Medicine, Western University of Health Sciences, Pomona, CA, USA Abstract: Our previous studies have established the efficacy of chemopreventive regimens of aspirin and curcumin (CUR) encapsulated within solid lipid nanoparticles (SLNs) in combination with free sulforaphane (ACS combination) to prevent or delay the initiation and progression of pancreatic cancer, classified as one of the deadliest diseases with very low chances of survival upon diagnosis. Although toxicity of individual drugs and SLN has been studied previously, there are no studies in current literature that evaluate the potential toxicity of a combined regimen of ACS, especially when encapsulated within chitosan-SLNs (c-SLNs). Hence, objective of the current study was to investigate the potential toxic effects of ACS c-SLN combined chemopreventive regimens following acute (3 days), subacute (28 days), and subchronic (90 days) administrations by oral gavage in BALB/c mice. Mice were administered the following regimens: saline, blank c-SLN, low-dose ACS c-SLN (2+4.5+0.16 mg/kg), medium-dose ACS c-SLN (20+45+1.6 mg/kg), and high-dose ACS c-SLN (60+135+4.8 mg/kg). The potential toxicity was evaluated based on animal survival, body weight, hematology, blood chemistry, and organ histopathology. During 3-day, 28-day, and 90-day study periods, no animal deaths were observed. Treatment with ACS c-SLNs did not cause alteration in complete blood counts and blood chemistry data. Histopathological examination of various organ sections (pancreas, heart, liver, kidney, and brain) appeared normal. Based on the results of this study, no signs of toxicity in acute, subacute, and subchronic studies following oral administration of ACS c-SLNs were found indicating that the oral dosing regimens were safe at the levels tested for long-term administration to prevent the onset of pancreatic cancer. Keywords: pancreatic cancer, toxicity, chitosan-solid lipid nanoparticle, aspirin, curcumin, sulforaphan