Due to their excellent electrical properties, metallic carbon nanotubes are promising materials for interconnect wires in future integrated circuits. Simulations have shown that the use of metallic carbon nanotube interconnects could yield more energy efficient and faster integrated circuits. The next step is to build an experimental prototype integrated circuit using carbon nanotube interconnects operating at high speed. Here, we report the fabrication of the first stand-alone integrated circuit combining silicon transistors and individual carbon nanotube interconnect wires on the same chip operating above 1 GHz. In addition to setting a milestone by operating above 1 GHz, this prototype is also a tool to investigate carbon nanotubes on a silicon-based platform at high frequencies, paving the way for future multi-GHz nanoelectronics.

Carbon-based nanomaterials such as metallic singlewalled carbon nanotubes, multiwalled carbon nanotubes (MWCNTs), and graphene have been considered as some of the most promising candidates for future interconnect technology because of their high current-carrying capacity and conductivity in the nanoscale, and immunity to electromigration, which has been a great challenge for scaling down the traditional copper interconnects. Therefore, studies on the performance and optimization of carbon-based interconnects working in a realistic operational environment are needed in order to advance the technology beyond the exploratory discovery phase. In this paper, we present the first demonstration of graphene interconnects monolithically integrated with industry-standard complementary metal-oxide-semiconductor technology, as well as the first experimental results that compare the performance of high-speed on-chip graphene and MWCNT interconnects. The graphene interconnects operate up to 1.3-GHz frequency, which is a speed that is commensurate with the fastest high-speed processor chips today. A low-swing signaling technique has been applied to improve the speed of carbon interconnects up to 30%.

The prevalence of both thyroid papillary cancer and adenomatous lesions was greater in the patients with Hashimoto's thyroiditis than in those with Graves' disease; and adenomatous lesions were more frequent in younger patients with Hashimoto's thyroiditis. We recommend performing US at the time of the initial visit in patients with autoimmune thyroid disease, who have a high prevalence of thyroid papillary carcinoma, to detect malignant thyroid tumors and adenomatous lesions.

Primary mucoepidermoid carcinoma (MEC) of the thyroid is very rare, and its origin has not been fully determined. We report a case of MEC, the origin of which was demonstrated by thyroid specific genes expressed in a metastatic lymph node. A 52-year-old male presented with chest pain, weight loss and diffuse goitre. Ultrasonography showed the thyroid to be diffusely enlarged with numerous small calcifications. The tumour was found to be infiltrating the thyroid, lung, lymph nodes and first thoracic vertebra. A variant type of papillary thyroid carcinoma was suspected by fine needle aspiration cytology of the thyroid. An open biopsy specimen from an axillary lymph node revealed the tumour to be composed of three distinct cell types: mucin-producing cells, intermediate cells and a small amount of epidermoid cells with scattered psammoma bodies. Immunohistochemical studies showed the tumour cells to be negative for thyroglobulin and calcitonin, but positive for CEA. To examine the primary origin of the tumour, the expression of thyroid specific genes in the lymph node specimen was examined by RT-PCR. TTF-1, TTF-2, Pax-8, Na-I symporter and thyroid peroxidase mRNA were detected. The presence of these thyroid-specific mRNAs indicates that this MEC originated from thyroid follicular epithelium. This is the first molecular evidence of dedifferentiation from thyroid follicular cells to MEC.

The results of this study raise the possibility that M15+I is superior to M30 as a primary treatment for moderate to severe hyperthyroidism caused by GD.

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Secure digital chips such as those found in smart cards are widely used for financial transactions and the transfer of confidential information. Small circuits for high-level information security have to be implemented in these chips. These secure circuits thus require a small ph-RNG (physical random-number generator) capable of generating unpredictable random numbers. A smart card of just a few mm 2 is almost entirely occupied by the CPU, coprocessor, random logic, ROM, RAM, EEPROM, etc., and the memory capacity required is increasing. However, the circuit area of previous ph-RNGs is large, since there is a complex trade-off among circuit area, quality of random numbers and data generation rate. To solve the tradeoff, we use SiN MOSFET as a noise source device, and design a compact A/D converter for SiN MOS-FET RNG. Together these components form a compact ph-RNG circuit as small as 1200μm 2 with a generation rate of 2Mb/s. This ph-RNG circuit area is smaller than one-third of that of any ph-RNG previously reported [1][2][3][4][5], compared at the same generation rate. Furthermore, the quality of random numbers generated by the SiN MOSFET ph-RNG does not depend on temperature, since the origin of random noise signal is a direct tunneling process, theoretically independent of temperature, whereas the origin of random noise in previous ph-RNG is from thermal processes.Previous ph-RNGs are based on thermal noise or thermal carrier injection/ejection in a single or few local traps [1][2][3][4][5]. These noise signals are very small, especially at high frequency, although large noise signals at high frequency are better for a ph-RNG. We use a MOSFET with high-density electron traps in a SiN layer near a Si channel for a noise source ( Fig. 22.8.1). The SiN layer is formed by the same CVD used in the conventional CMOS mass-production process. The SiN MOSFET is fabricated with a CMOS process and one additional photo mask. Electrons are injected/ejected quickly between the Si channel and local traps in SiN layer by direct tunneling. According to electron injection/ejection in many local traps, a large conductance change in the transistor is seen as a large drain current (I d ) fluctuation in the SiN MOSFET. The noise signal of SiN MOSFET is much larger than that of a conventional MOSFET, as shown in Fig. 22.8.1. The circuit blocks for conventional ph-RNG and the SiN MOSFET one are shown in Fig. 22.8.2. Most conventional ph-RNGs require large amplification of the noise signal or a large array of identical noise generators and A/D converters in order to attain over 1Mb/s generation rate, since the noise signals are very small at high frequency. As a result, the amplifier or A/D converter has been very large. In this work, because of the high-amplitude random noise at high frequency from the SiN MOSFET, we need only a single amplifier and A/D converter, and the amplifier area is decreased, as shown in Fig. 22.8.2.In addition to an amplifier and A/D converter, a RNG also needs filters to cut off low-frequency noise origina...

In this Japanese population, we did not find an evident association between ABCG2 polymorphisms, c.376C > T and c.421C > A, and susceptibility to gefitinib-induced adverse effects.