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We present a 2.4 GHz unbalanced loop antenna that can be stretched along multiple dimensions simultaneously. It was realized by incorporating room temperature liquid metal alloy into microstructured channels in an elastic material. The demonstrated prototype exhibits a stretchability of up to 40% along two orthogonal orientations as well as foldability and twistability. Port impedance and radiation characteristics of the nonstretched and stretched antenna were studied numerically and experimentally. Measured results indicate a radiation efficiency of more than 80%.

BackgroundMedicinal plant trade is important for local livelihoods. However, many medicinal plants are difficult to identify when they are sold as roots, powders or bark. DNA barcoding involves using a short, agreed-upon region of a genome as a unique identifier for species– ideally, as a global standard.Research QuestionWhat is the functionality, efficacy and accuracy of the use of barcoding for identifying root material, using medicinal plant roots sold by herbalists in Marrakech, Morocco, as a test dataset.MethodologyIn total, 111 root samples were sequenced for four proposed barcode regions rpoC1, psbA-trnH, matK and ITS. Sequences were searched against a tailored reference database of Moroccan medicinal plants and their closest relatives using BLAST and Blastclust, and through inference of RAxML phylograms of the aligned market and reference samples.Principal FindingsSequencing success was high for rpoC1, psbA-trnH, and ITS, but low for matK. Searches using rpoC1 alone resulted in a number of ambiguous identifications, indicating insufficient DNA variation for accurate species-level identification. Combining rpoC1, psbA-trnH and ITS allowed the majority of the market samples to be identified to genus level. For a minority of the market samples, the barcoding identification differed significantly from previous hypotheses based on the vernacular names.Conclusions/SignificanceEndemic plant species are commercialized in Marrakech. Adulteration is common and this may indicate that the products are becoming locally endangered. Nevertheless the majority of the traded roots belong to species that are common and not known to be endangered. A significant conclusion from our results is that unknown samples are more difficult to identify than earlier suggested, especially if the reference sequences were obtained from different populations. A global barcoding database should therefore contain sequences from different populations of the same species to assure the reference sequences characterize the species throughout its distributional range.

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successfully implemented. It has a simple configuration and is easy to fabricate. The approaches to achieve optimization for the proposed antenna are completed via simulation, and the experimental results show wide bandwidth of approximately 61% and 29% for both lower and upper band, respectively. ACKNOWLEDGMENTThe authors thank Yuan-Pu Hsieh for his assistance in completing the design of this antenna. ABSTRACT: Artificial immune systems are classified as computational systems inspired by theoretical immunology and are mechanisms that can solve complex problems. Clonal selection algorithm is a selection algorithm, which is derived as a special selection algorithm to this artificial intelligence concept. In this work, Clonal selection algorithm is applied to design a simple microwave matching network for a load with arbirtary impedance. The results obtained were tested in a microwave simulator and indicated that clonal selection algorithm can be very effectively applied for microwave design problems.

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A highly efficient microfluidic 3D electrically small antenna is created using a simple fabrication technique. It is easy to construct simply by pneumatically inflating a planar microfluidic antenna into a spherical cap. It has premium performance around its hemispherical shape, combining a wide working band with high efficiency.

A quarter-wave transversal slot in the center of a handheld terminal ground plane is proposed and evaluated as a wideband antenna for low profile mobile phones. By feeding the slot with a microstrip line, a triple-resonance response is obtained from the chassis, slot and microstrip stub interaction, providing sufficient impedance bandwidth and radiation efficiency to cover the 0.9-2.7 GHz frequency range. While the introduction of a slot in the ground plane has many advantages over e.g. PIFA or patch structures, both in terms of performance and cost, the circuit floor planning becomes more complicated. To address this problem, a possible solution in terms of module partitioning and signal line routing is suggested. In addition, simulations of parasitic antenna to signal line coupling and techniques to reduce this effect are presented.