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Minoru Kawaguchi1,2, Jun Ohno2,3, Akihito Irie4, Tadao Fukushima2,5, Jun Yamazaki2,6, Naotoshi Nakashima2,71Department of Dental Engineering, Biomaterials Section, Fukuoka Dental College, Sawara-ku, Fukuoka, Japan; 2Japan Science and Technology Agency (JST), Core Research of Evolutional Science and Technology (CREST), Chiyoda-ku, Tokyo, Japan; 3Department of Morphological Biology, Pathology Section, Fukuoka Dental College, Sawara-ku, Fukuoka, Japan; 4Department of Oral Rehabilitation, Section of Oral Implantology, Fukuoka Dental College, Sawara-ku, Fukuoka, Japan; 5Department of Dental Engineering, Bioengineering Section, Fukuoka Dental College, Sawara-ku, Fukuoka, Japan; 6Department of Physiological Science and Molecular Biology, Section of cellular and Molecular Regulation, Fukuoka Dental College, Sawara-ku, Fukuoka, Japan; 7Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Nishi-ku, Fukuoka, JapanAbstract: Carbon nanotubes act as a photon antenna that serves as an effective “molecular heater” around the near-infrared (NIR) region. This exothermic generation can be used as a possible heating source for hyperthermia therapy. The current study reports the dispersible and exothermic properties with NIR irradiation for single-walled carbon nanotubes (SWNTs) treated with a strong acid (acid-treated SWNTs), and the SWNTs further functionalized with double-stranded DNA (DNA-functionalized SWNTs: DNA-SWNTs). DNA-SWNTs significantly improved the dispersibility of SWNTs when compared with the acid-treated SWNTs. The binding ratio of the acid-treated SWNT and DNA was calculated to be 3.1 (DNA/SWNTs) from the phosphorous content in the DNA-SWNT. This interaction of the SWNTs and DNA would contribute to the stable dispersion of the DNA-SWNTs in a culture medium. With NIR irradiation by a halogen lamp light source, the acid-treated SWNTs and the DNA-SWNTs showed strong heat evolution in vitro (in a culture medium) and in vivo (in the subcutaneous tissue of a mouse) condition without any invasive effect on the non-SWNT area. The results of this study suggested that the functionalization with DNA was an efficient approach to improve the dispersibility of SWNTs in body fluids, and the DNA-SWNT would be a promising source for photo-induced exothermic generation.Keywords: DNA functionalization, near-infrared irradiation

A rectenna designed for wireless power transfer at 900 MHz focuses on conjugate impedance matching and image impedance matching for improved efficiency. To do them, a voltage doubler rectifier circuit (VD) and a planar monopole antenna (PMA) were engineered with the same pure resistance value and integrated into the rectenna. The input impedance of the VD with 30 Ω load resistance indicated a pure resistance of approximately 73 Ω. This value closely matches the input impedance of a dipole antenna operating as a pure resistor. Since the prototype rectifier circuit is unbalanced, the authors constructed a PMA, an unbalanced antenna similar to a dipole antenna, on a double‐sided circuit board. In this setup, a microstrip line was created by extending the radiating element, achieving the impedance matchings. Measurements indicated a voltage standing wave ratio of approximately 1.03. A rectenna efficiency of 37.4% was observed for a transmission distance of 50 cm. The rectification efficiency of the VD is nearly 0% when the input power is less than −20 dBm, and the received power of the PMA is less than −20 dBm when the transmission distance is 60 cm or more. It is predicted that the rectenna efficiency will be 0% when the transmission distance is 60 cm or more. However, the rectenna efficiency was 24.6% when the transmission distance was 60 cm. This over 20% improvement is due to the connection between the PMA and the VD using pure resistance. Key Points: This study introduces the development of an integrated rectenna for RF WPT focus on achieving impedance matching to enhance efficiencyPure resistance was employed in both a voltage doubler rectifier circuit and a planar monopole antenna designMeasurements revealed that an efficiency enhancement is achieved by approximately 20% [ABSTRACT FROM AUTHOR]

Aims: Abnormalities involving proliferation, apoptosis, and angiogenesis are important in tumorigenesis. The purpose of this study was to examine these three biological processes, and their relation with the clinical stage [...]