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• The essential elements required for any sensors are a receptor, a signal converter, and a detector. • Bacteria binding-induced conformational changes in supramolecular state is translated into fluorescence emission. • Bacteria binding-induced conformational changes in supramolecular state is translated into fluorescence emission. • fSBs were resistant to heat-induced denaturation and retained their bacterial-sensing capability even at high temperature. The essential elements required for any sensors are a receptor, a signal converter, and a detector. Here, we report the construction of bacterial biosensors in which all of the required biosensor elements are furnished in one supramolecular assembly. The supramolecular biosensor is based on a double-layered octa-helical coiled-coil peptide assembly that contains tetravalent bioreceptors on the outer surface and environment-sensitive fluorophores in the core. The signal conversion takes advantage of the noncovalent and reversible nature of the self-assembled system, i.e., the multivalent binding of bacteria induces conformational changes in the supramolecular state, which is translated into differential fluorescence emissions. We show that fluorescent supramolecular biosensors (fSBs) can selectively detect E. coli over other bacteria. Because the fSBs were resistant to heat-induced denaturation, they retained their bacterial-sensing capability even at an elevated temperature (50 ℃). Biosensors based on responsive supramolecular assemblies can be further developed to detect various large and flat biological objects and biomacromolecules. [ABSTRACT FROM AUTHOR]

In this letter, we present the 2 by 1 and 2 by 2 array microstrip patch antennas using the waveguide endwall coupler at 24 GHz. These antennas consist of a waveguide feed and two or four patches that are excited by the endwall coupler. As the measured results, the 2 by 2 array antenna has the gain of 10.7 dBi and the bandwidth of 1.3 GHz, and half power beamwidth is 31° on the E-plane and 35° on the H-plane. Because this transition technique is very simple and easy to fabricate, it can be used for low cost and high volume production for commercial millimeter-wave applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:630-633, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25794 [ABSTRACT FROM AUTHOR]

In this article, the compact ultra-wideband (UWB) antenna with band notch characteristic and the miniaturized antenna are proposed. To realize the stop band, the spoon-shaped slots are inserted in the pattern of planar monopole antenna. These antennas are operating in the UWB spectrum from 3.1 to 10.6 GHz and has the stop band from 4.8 to 6.3 GHz where VSWR is higher than 3. They are made by low-temperature cofired ceramic process, and the size of the miniaturize antenna is 8 × 15 × 1 mm3. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 717–720, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24190 [ABSTRACT FROM AUTHOR]

ABSTRACT A CMOS transceiver is designed and fabricated for implantable cardioverter telemetry service. For the image rejection, a complex filter is used in the receiver instead of the conventional image rejection mixer type. Low power consumption is essential for the implantable medical service, thus the RF blocks such as the low noise amplifier, voltage controlled oscillator, and frequency synthesizer are designed by focusing on the low power operation. The transceiver is implemented in 0.18-µm CMOS process, and operates with a single 1.8-V supply. The sensitivity is −85 dBm. The phase noise characteristic of frequency synthesizer is −87 dBc/Hz at 10 kHz offset frequency. Maximum output power of the transmitter is −2.8 dBm. The transceiver achieves 500 kbps maximum data rate with 22 mW power consumption. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2580-2582, 2014 [ABSTRACT FROM AUTHOR]

The target affinity and selectivity of many biomacromolecules depend on the three-dimensional (3D) distribution of multiple ligands on their surfaces. Here, we devised a self-assembly strategy to control the target-tailored 3D distribution of multiple α-helical ligands on a coiled-coil core scaffold using novel lariat-type supramolecular building blocks. Depending on the coiled-coil composition and ligand grafting sites in the lariat building blocks, the structural and functional features of the self-assembled peptide nanostructures (SPNs) could be variably fine-tuned. Using oligovalent protein-RNA (Rev-RRE) interactions as a model system, we demonstrate that longer grafting reinforces the helicity of the peptide ligands, whereas shorter grafting strengthens the target binding affinity of the SPNs in both monovalent and oligovalent interactions. This supramolecular approach should be useful in developing precisely controllable multivalent ligands for biomacromolecular interactions.