A sustainable cold-sintering process was adopted to fabricate composites of (1–x)­SrFe12O19–xLi2MoO4, x = 0.4, 0.5, 0.6, and 0.7 with density up to 91%, and their broad-band electromagnetic properties were deciphered. X-ray diffraction (XRD) analysis revealed the coexistence of SrFe12O19 (SFO) and Li2MoO4 (LMO) phases in the composites, unaccompanied by any additional phases. The evolution of microstructure facilitating enhanced densification was observed with an increase in the LMO volume fraction. The real permittivity (ε′) increased with an increase in the LMO volume fraction, while the dielectric loss (tan δε) decreased. Further, the real permeability (μ′) of all of the composites is greater than unity and the magnetic loss (tan δμ) is of the order of 10–2. The 0.3SFO–0.7LMO composite with the highest densification possess ε′ = 6.7, tan δε = 2 × 10–3, μ′ = 1.14, and tan δμ = 2 × 10–2 at 900 MHz along with an appreciable room-temperature saturation magnetization (M s) of 32.2 emu/g. To demonstrate the application potential of this magnetodielectric composite toward microwave antenna applications, a ferrite resonator antenna (FRA) integrated using the SFO–LMO composite was designed, simulated, and fabricated. The fabricated FRA resonating at 12.89 GHz exhibited an exceptionally high return loss of −40 dB and a wide impedance bandwidth of 510 MHz. The remarkable properties of the fabricated ferrite resonator antenna suggest that it is a potential candidate for Ku-band applications.

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The electromagnetic interference (EMI) shielding market is one of the fast-growing sectors owing to the increasingly complicated electromagnetic environment. Recently, priority has been given to improvise the techniques to fine-tune and predict the shielding properties of structures without exhausting raw materials and reduce the expense as well as the time required for optimization. In this article, we demonstrate an effective and precise method to predict the EMI shielding effectiveness (SE) of materials via simulating the performance of composites having alternate layers of conducting and magnetic materials in a virtual waveguide measurement environment based on the finite element method (FEM). The EMI SE of multilayered heterogeneous arrangements (MHAs) is simulated in the Kband region using ANSYS High Frequency Structure Simulator (HFSS) software, which can be extended to all other bands as well. Various simulations carried out by changing the order of the conducting and magnetic layers and the number of layers revealed that the strategic arrangement of electromagnetic (EM) energy-trapping layers inside the impedance-matching layers in the MHAs significantly contributes toward the enhancement of absorption-dominated EMI shielding. Among the MHAs, the conductingmagnetic-conducting (CMC) systems exhibited the highest shielding effectiveness of above 50 dB. The MHAs are realized for testing using poly(vinylidene fluoride)-based composites of low-cost carbon black and barium hexaferrite, an easily accessible ferrite. Through this study, we propose the idea that materials with high production cost and cumbersome fabrication procedures are not necessary to realize highly efficient shielding materials.

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Background. Reduced UES opening is a well-known risk factor for dysphagia. The Shaker exercise and the CTAR are the widely used intervention strategies to bring about effective UES opening. But there are well-known difficulties with the clinical use of these two exercise regimes. The present study proposes a clinical alternative to Shaker’s exercise and CTAR called the forehead against resistance (FAR) and its variants without altering the central principles of these two regimes. The aim of the present study was to investigate the efficacy of FAR and its variants in bringing about UES opening. Method. The study used a comparative cross-sectional study design, with the nonrandomized convenient sampling that included 27 healthy adults. MBS was carried out in the anterior-posterior and lateral views, while the participants performed FAR and its variants. The UES diameter was measured in the baseline and with the subjects performing FAR maneuver and its variants. Results. The result revealed that the participants had greater UES opening on FAR and its variant than the baseline swallow. Also, mean values of UES opening were greater for FAR with chin tuck when compared to FAR alone, although there was no significant main effect with exercise. Conclusion. FAR and its variant could be one of the options for increasing UES opening in individuals with dysphagia.

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Computer keyboards of a teaching laboratory were examined and bacteria were isolated from computer keyboards. The subsequent tests were done for the bacterial isolates: methyl red, vogus proskaur, citrate utilization, urease and TSI. This study paves the way to look at an inanimate object like computer keyboard as potential reservoir of bacteria.