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Metamaterials are artificially structured composite materials that show unusual properties not usually available in natural materials. In general, metamaterial structures and properties are anisotropic. A waveguide filled with an anisotropic metamaterial shows unique properties not achievable in conventional waveguides, such as propagation of backward waves and modes below the cut-off frequencies of the conventional fundamental mode, zero group velocity etc. The waveguide filler material can be anisotropic with the tensorial permittivity and permeability components having positive or negative values, and combinations thereof, giving rise to a rich variety of phenomena. Further, modes in a cylindrical waveguide filled with a hyperbolic metamaterial are described by unusual Bessel modes of complex orders. In many situations, the wave propagating region is isotropic, and it is enclosed by anisotropic metamaterials with different thicknesses and contrarily the propagating region is might be anisotropic that is enclosed by isotropic in some other situations. Various metamaterial waveguide geometries like a pair of parallel plates, waveguides with rectangular or cylindrical cross-section filled with anisotropic metamaterials as well as hollow-core waveguides with metamaterial claddings or linings have been demonstrated experimentally. The anisotropy can be uniaxial or biaxial depending on the orientation of structure. Here we review the advances in the theory and applications of waveguides filled with subwavelength structured metamaterials with anisotropic or even hyperbolic properties across the electromagnetic spectrum. By examining the field behaviour in such waveguides, connection is made to the extraordinary transmission of light through arrays of subwavelength sized apertures in a metallic screen. Potential applications range from enhanced MRI imaging and electromagnetic shielding at radio frequencies to intriguing imaging applications and efficient coupling of the emitted radiation from small sources into waveguides at optical frequencies.

Biomass–fungi biocomposite materials are derived from sustainable sources and can biodegrade at the end of their service. They can be used to manufacture products that are traditionally made from petroleum-based plastics. There are potential applications for these products in the packaging, furniture, and construction industries. In the biomass–fungi biocomposite materials, the biomass particles (made from agricultural waste such as hemp hurd) act as the substrate, and a network of fungal hyphae grow through and bind the biomass particles together. Typically, molding-based methods are used to manufacture products using these biocomposite materials. Recently, the authors reported a novel extrusion-based 3D printing method using these biocomposite materials. This paper reports a follow-up investigation into the effects of mixing parameters (mixing time and mixing mode) on fungal growth in biomass–fungi mixtures prepared for 3D printing and the effects of printing parameters (printing speed and extrusion pressure) on fungal growth in printed samples. The fungal growth was quantified using the number of fungal colonies that grew from samples. The results show that, when mixing time increased from 15 to 120 s, there was a 52% increase in fungal growth. Changing from continuous to intermittent mixing mode resulted in an 11% increase in fungal growth. Compared to mixtures that were not subjected to printing, samples printed with a high printing speed and high extrusion pressure had a 14.6% reduction in fungal growth, while those with a low printing speed and low extrusion pressure resulted in a 16.5% reduction in fungal growth. [ABSTRACT FROM AUTHOR]

Several applications of a cylindrical waveguide filled with inhomogeneous materials have been demonstrated. Analytical solutions for modes, an inhomogeneous cylindrical waveguide, are available only for a few material parameters and those are also mostly approximations. We have obtained exact analytical solutions for cylindrical waveguides filled with different inhomogeneous and anisotropic material parameters. Different sets of material parameters are obtained using the geometric transformation method. The analytical and numerical modal field distributions, the value of cutoff frequencies and effective mode indices for different propagating modes are well matched to each other. The inhomogeneity can be used to miniaturize the radial dimensions of the waveguide. This is highly desirable for many applications like sensing, near-field coupling and magnetic resonance imaging (MRI). [ABSTRACT FROM AUTHOR]

Designing a low frequency broadband absorber is a nontrivial task in terms of establishing a trade‐off between overall absorber thickness, wide absorption bandwidth, and miniaturized unit cell size. To address the issue, we propose a novel broadband absorber design based on multilayered configuration, which covers the lower bands of the radar spectrum. The design is implemented using resistive ink patterns that are printed on an economical FR4 substrate. The reflectivity response of the proposed broadband absorber is less than −10 dB in the frequency range 1.26 to 4.38 GHz, covering the L and S bands of the radar spectrum with a fractional bandwidth of 110.63%. Furthermore, the structure has a miniaturized unit cell of dimension 0.057λL and a notable small thickness of 0.079λL. The implementation of the equivalent circuit model further validates the proposed design. The design is fabricated and experimentally verified. The simulation and measured results are in good congruence with each other. [ABSTRACT FROM AUTHOR]

Metamaterials are artificially structured composite materials that show unusual properties not usually available in natural materials. In general, metamaterial structures and properties are anisotropic. A waveguide filled with an anisotropic metamaterial shows unique properties not achievable in conventional waveguides, such as propagation of backward waves and modes below the cut-off frequencies of the conventional fundamental mode, zero group velocity etc. The waveguide filler material can be anisotropic with the tensorial permittivity and permeability components having positive or negative values, and combinations thereof, giving rise to a rich variety of phenomena. Further, modes in a cylindrical waveguide filled with a hyperbolic metamaterial are described by unusual Bessel modes of complex orders. In many situations, the wave propagating region is isotropic, and it is enclosed by anisotropic metamaterials with different thicknesses and contrarily the propagating region is might be anisotropic that is enclosed by isotropic in some other situations. Various metamaterial waveguide geometries like a pair of parallel plates, waveguides with rectangular or cylindrical cross-section filled with anisotropic metamaterials as well as hollow-core waveguides with metamaterial claddings or linings have been demonstrated experimentally. The anisotropy can be uniaxial or biaxial depending on the orientation of structure. Here we review the advances in the theory and applications of waveguides filled with subwavelength structured metamaterials with anisotropic or even hyperbolic properties across the electromagnetic spectrum. By examining the field behaviour in such waveguides, connection is made to the extraordinary transmission of light through arrays of subwavelength sized apertures in a metallic screen. Potential applications range from enhanced MRI imaging and electromagnetic shielding at radio frequencies to intriguing imaging applications and efficient coupling of the emitted radiation from small sources into waveguides at optical frequencies. [ABSTRACT FROM AUTHOR]

Introduction: Cirrhotic cardiomyopathy is characterised by increased baseline cardiac output, systolic and diastolic dysfunction, diminished cardiovascular response to stressful stimuli and electrophysiological abnormalities in patients of cirrhosis in the absence of any underlying cardiac disease. QTc prolongation has been described as a common electrocardiographic abnormality in cirrhosis patients. Aims and Objectives: This study was done to evaluate the prevalence of QTc changes in patients of cirrhosis coming to a rural tertiary care centre and to analyse its correlation with disease severity. Materials and Methods: The present study was conducted on 100 patients suffering from cirrhosis of liver presented to the department of medicine. Around 100 age and sex-matched individuals were recruited as controls. The Child-Pugh score was used to determine the disease severity in cirrhosis patients. Standard 12-lead ECG was recorded in all cases and controls. Results: Prolongation of QTc interval on ECG was observed in the majority (80%) of cirrhosis patients and it was significantly higher as compared to the healthy controls (P <0.01). The prolongation of QTc was significantly associated with the duration of disease (P <0.05) and disease severity as measured by the Child-Pugh score (P <0.01). Conclusion: QTc prolongation on ECG may be an early marker of cardiac involvement in patients of cirrhosis and is significantly associated with disease severity. [ABSTRACT FROM AUTHOR]

Charlotte Bronte's Jane Eyre has had a significant and noteworthy presence in cultural memory and imagination, ever since its publication in the nineteenth century, while the reception of the novel has differed across different temporal contexts. The preponderance of the novel in cultural imagination has led to the writing of a considerable number of inspired works, and as some scholars argue, one can discern traces of Jane Eyre in works that do not explicitly establish a literary lineage with the Victorian classic. This paper explores the latter kind of literary nexus with respect to the works of Margaret Atwood. [ABSTRACT FROM AUTHOR]