•Characterization of a novel metamaterial inspired by RLC-based resonator geometry.•A new tunnel structured strategy is introduced for designing the metamaterial.•Resonance can shift to the lower ...frequency band from higher frequency band.•Proposed metamaterial structure can increase the negative refractive index•Large electric and magnetic fields in tunnel area and exhibits better performance
A narrow metal strip inspired by the left-handed metamaterial and sensitive LC resonator structure has been released in this work where the narrow metal strip is presented as a tunnel structure which can enhance electric and magnetic properties. A commercially available electromagnetic simulator CST Microwave Studio is utilized to design and investigate the eSRR (electric split-ring resonator) and tunnelled LC resonator structures. Furthermore, ADS (Advance Design software) is used to determine the scattering parameters of the equivalent circuit. The proposed metamaterial structure is employed as a sensor operating in the C-band (6.88 GHz) of the microwave region, and its sensing properties are tested using glossy paper as an obstacle. The designed metamaterial tunnelling structure exhibits very high sensitivity toward dielectric obstacles at different rotational angles and thus can be potentially used in various sensing applications. The field enhancement effects on sensing application are verified by measured obtained results for eSRR and tunnelled LC resonator structures.
The mariner transposon family of Himar1 has been widely used for the random mutagenesis of bacteria to generate single insertions into the chromosome. Here, a versatile toolbox of mariner transposon ...derivatives was generated and applied to the functional genomics investigation of fish pathogen Edwardsiella piscicida. In this study, we combined the merits of the random mutagenesis of mariner transposon and common efficient reporter marker genes or regulatory elements, mcherry, gfp, luxAB, lacZ, sacBR, and P
and antibiotic resistance cassettes to construct a series of derivative transposon vectors, pMmch, pMKGR, pMCGR, pMXKGR, pMLKGR, pMSGR, and pMPR, based on the initial transposon pMar2xT7. The function and effectiveness of the modified transposons were verified by introducing them into E. piscicida EIB202. Based on the toolbox, a transposon insertion mutant library containing approximately 3.0 × 10
separated mutants was constructed to explore the upstream regulators of esrB, the master regulator of the type III and type VI secretion systems (T3/T6SS) in E. piscicida. Following analysis by Con-ARTIST, ETAE_2184 (renamed as EsrR) was screened out and identified as a novel regulator mediating T3SS expression. In addition, the esrR mutants displayed critical virulence attenuation. Due to the broad-range host compatibility of mariner transposons, the newly built transposon toolbox can be broadly applied for functional genomics studies in various bacteria.
•The first 3D model to study multiphysics in an industrial ESRR process.•The MHD, thermal, and solidification in the ESRR are investigated.•The impact of formation of the slag skin on the electric ...current path is analyzed.•A fairly symmetric melt pool profile of the billet ingot is observed.•Modeling results are verified by experiments.
This paper presents a numerical model (3D) incorporating multiphysics for an electroslag rapid remelting (ESRR) process of industrial scale. The electromagnetic field is calculated in the whole system including the electrode, molten slag, ingot, graphite ring, and mold; the interaction between the turbulent flow and electromagnetic field is calculated for all fluid domains (molten slag and melt pool); the thermal field is calculated in the molten slag, ingot and mold. The solidification of the billet ingot and the formation of solid slag skin layer along the T-mold are considered as well. The formation of the skin layer adjacent to the T-mold can remarkably impact the electric current path in the whole system. The modeling result indicates that no skin layer would form on the graphite ring, as the local electric current density is very high. In contrast, a thick slag skin layer forms along the inclined part of the T-mold, blocks the electric current path there. Those modeling results are verified by experiments. A typical non-axis symmetry flow/thermal field in the slag region, which has been observed in-situ from the slag surface during operation, is predicted. Detailed analyses of the quasi-steady state results of flow/thermal fields are presented. A symmetric melt pool (profile of the solidifying mushy zone) of the ingot is predicted, which agrees with the experiments.
Novel design techniques for tunable and fixed frequency notch band filters are presented and validated with experiments. A notch band filter based on an Embedded Split Ring Resonator (ESRR) in a ...Microstrip Transmission Line (MTL) is presented. The physical dimensions of the ESRR determine the filter resonance frequency, which, when combined with a Varactor (Varactor Loaded ESRRs or VLESRRs), provides a continuously tunable resonance frequency. Tunable notch bands centered from 1.7 GHz to 4.8 GHz are obtained with resonators having an unprecedented electric length of <inline-formula> <tex-math notation="LaTeX">0.05~\lambda _{0} </tex-math></inline-formula> at the lowest frequency, corresponding to a physical length of 7 mm and a total occupied area of 8.5 mm 2 . Two or more ESRRs are proposed to provide a deeper single notch band, a wider notch band, and/or multi notch bands. The proposed ESRRs are used jointly with a trapezoidal antenna to form 1) a notch band at 2.5 GHz; and, 2) dual notch bands at 2.5 GHz and 3.5 GHz. In addition, ESRRs are used in a Low Pass Filter (LPF) with cutoff frequency of 1 GHz to suppress undesired harmonic at 3.46 GHz and improve band rejection. The proposed MTL loaded by ESRRs, LPF and trapezoidal antenna are fabricated, measured and the results of simulations and measurements are in good agreement.
A new design of compact micro strip antenna, based on a newly structure "E"SRR of metamaterial is proposed and designed using CST Microwave Studio. It has been found that the characteristics of new ...micro strip antenna with novel designed metamaterials placed in the same plane as the radiating element are comparable to the conventional patch antennas, whereas its gain, directivity, and radiating efficiency are remarkably improved. For the design and fabricated antenna, it shows that with the addition of split ring resonator, the frequency has been shifted from 2.38 GHz to 2.4 GHz. The return loss of this antenna increased from −60 dB to −70 dB. The realized gain increased from 7.1 dbi for the antenna alone to 7.31 dbi for the meta‐material antenna. Prototype for all antennas are fabricated and measured. Good agreement between the measured and simulated results is achieved.
In this paper, CPW-Fed ultra wideband (UWB) planar monopole antenna (PMA) loaded by double elliptical split ring resonators (ESRRs) for double band-notch characteristics is introduced and examined. ...Two different ESRRs with different dimensions are printed in the antenna backside to notch two different frequencies. The ESRRs are also rotated and the corresponding return loss effect is examined. Different notch frequencies can be obtained by varying the ESRRs, dimensions. Two single SRRs are used to notch two frequencies instead of using dual SRR pairs. Two notch frequencies at 5.2 GHz and 6.9 GHz has been obtained to notch WLAN and C-band wireless applications, respectively. A directive radiation pattern in E-plane and omnidirectional radiation patterns in the H-plane could be observed. Also the gain is suppressed in the notch frequencies. The group delay is nearly stable in the UWB frequency range, except at the notch frequencies, which is distorted sharply. So, the proposed antenna is a good candidate for the modern UWB systems. Finite element method FEM and finite integration technique FIT are used to simulate the proposed structures through the usage of Ansys HFSS and CST MWS. Very good agreement between both results has been obtained.
Objective: A non-synonymous single nucleotide polymorphism (rs61742642; C to T, P386S) in the ligand-binding domain of human estrogen-related receptor beta (ESRRβ) showed possible association to ...noise-induced hearing loss (NIHL) in our previous study. Design: This study was conducted to examine the effect of the ESRRβ rs61742642 T variant on temporary threshold shift (TTS). TTS was induced by 10 minutes of exposure to audiometric narrow-band noise centered at 2000 Hz. Hearing thresholds and distortion product otoacoustic emissions input output function (DP IO) at 2000, 3000, and 4000 Hz were measured before and after the noise exposure. Study sample: Nineteen participants with rs61742642 CT genotype and 40 participants with rs61742642 CC genotype were recruited for the study. Results: Participants with the CT genotype acquired a significantly greater TTS without convincing evidence of greater DP IO temporary level shift (DPTLS) compared to participants with the CC genotype. Conclusion: The results indicated that the ESRRβ polymorphism is associated with TTS. Future studies were recommended to explore molecular pathways leading to increased susceptibility to NIHL.
In this paper, a compact ultra-wideband (UWB) antenna with triple notch bands is proposed. By etching out two ESRR of different dimensions in the radiating patch, two band-notched properties in the ...Wi-MAX (3-3.7 GHz), WLAN (5.125-5.825 GHz) are obtained. Furthermore, by placing SIR near the feed line-patch junction of the antenna, band notch property for the 7.9-8.4 GHz (X-band) frequencies is achieved. Design guidelines for implementing the notch-bands at the desired frequency regions are provided. The notched frequencies can be adjusted according to specification by altering the parameters of the ESRR and SIR. The effects of the key design parameters on band notch characteristics are also investigated. The realized antenna achieved an operating bandwidth (VSWR < 2) ranges from 2.94 to more than 11.3 GHz with triple notched bands of 3.0-3.7, 5.2-6.1, and 7.9-8.7 GHz. The proposed antenna is well designed and extensively investigated. The experimental results are given to verify that the proposed antenna with a wide bandwidth, three designated band-notched function which is suitable for modern high data rate UWB communication applications. The maximum simulated gain of the antenna is around 10.02 dBi with an average efficiency above 82.2% throughout the bandwidth.
Novel design techniques for tunable and fixed frequency notch band filters are presented and validated with experiments. A notch band filter based on an Embedded Split Ring Resonator (ESRR) in a ...Microstrip Transmission Line (MTL) is presented. The physical dimensions of the ESRR determine the filter resonance frequency, which, when combined with a Varactor (Varactor Loaded ESRRs or VLESRRs), provides a continuously tunable resonance frequency. Tunable notch bands centered from 1.5 GHz to 5 GHz are obtained with resonators having a length of 0.05 \boldsymbol{\lambda_{0}} at the lowest frequency.
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