Biological molecules can be used as versatile templates for assembling nanoscale materials because of their unique structures and chemical diversities. Supramolecular organization of molecular pigments, as is found in the natural light-harvesting antenna, has drawn attention for its potential applications to sensors, photocatalytic systems, and photonic devices. Here we show the arrangement of molecular pigments into a one-dimensional light-harvesting antenna using M13 viruses as scaffolds. Chemical grafting of zinc porphyrins to M13 viruses induces distinctive spectroscopic changes, including fluorescence quenching, the extensive band broadening and small red shift of their absorption spectrum, and the shortened lifetime of the excited states. Based on these optical signatures we suggest a hypothetical model to explain the energy transfer occurring in the supramolecular porphyrin structures templated with the virus. We expect that further genetic engineering of M13 viruses can allow us to coassemble other functional materials (e.g., catalysts and electron transfer mediators) with pigments, implying potential applications to photochemical devices.

The Multi-Threshold CMOS (MTCMOS) technology provides a solution to the high performance and low power design requirements of modern designs. While the low V th transistors are used to implement the desired function, the high V th transistors are used to cut off the leakage current. In this paper, we (i) examine the effectiveness of the MTCMOS technology for the Samsung's 0.18 m process, (ii) propose a new special flip-flop which keeps a valid data during the sleep mode, and (iii) develop a methodology which takes into account the new design issues related to the MTCMOS technology. Towards validating the proposed technique, a Personal Digital Assistant (PDA) processor has been implemented using the MTCMOS design methodology, and the 0.18 m process. The fabricated PDA processor operates at 333MHz, and consumes about 2 W of leakage power. Whereas the performance of the MTCMOS implementation is the same as that of the generic CMOS implementation, three orders of reduction in the leakage power has been achieved.

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Two 128 Mb dual-power-supply SRAM chips are fabricated in a 14 nm FinFET technology. A 0.064 m and a 0.080 m 6T SRAM bitcells are designed for high-density (HD) and high-performance (HP) applications. To improve of the high-density SRAM, a negative bitline scheme (NBL) is adopted as a write-assist technique. Then, the disturbance-noise reduction (DNR) scheme is proposed as a read-assist circuit to improve the of the high-performance SRAM. The 128 Mb 6T-HD SRAM test-chip is fully demonstrated featuring 0.50 with 200 mV improvement by NBL, and 0.47 for the 128 Mb 6T-HP with 40 mV improvement by the DNR. Improved reduces 45.4% and 12.2% power-consumption of the SRAM macro with the help of each assist circuit, respectively.

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Virtual platform (ViP), or ESL (Electronic System Level) simulation model, is one of the most widely renowned system level design techniques. In this paper, we present a case study of creating and applying the ViP in the development of a new hard disk system called Hybrid-HDD that is one of the main features in the Windows VISTA (R). First, we summarize how we developed the ViP including the levels of timing accuracy of models, automatic generation of models from RTL code, external subsystem models, etc. Then, we explain how we exploited the ViP in software optimization. Compared with the conventional flow of software development, e.g. based on the real board, the ViP gives a better profiling capability thereby allowing designers to find more chances of code optimization. Based on the simulation and analysis with the ViP, the software optimization could improve system performance by more than 50%. However, in our case study, we found that the current ViP technique needs further improvements to become a true ESL design technique.

Midface hypoplasia is one of the most significant sequelae of cleft lip and/or palate surgery. A complete understanding of the rate of orthognathic surgery across varying cleft phenotypes is a powerful tool for educating patients and families as to the treatment course that the patient will incur during their lifetime. Understanding the average rates of orthognathic intervention also can act to develop metrics for outcome evaluation with different treatment protocols. Attempting to identify the average rates of orthognathic intervention, the authors conducted a systematic review and meta-analysis by combining studies from 1987 to 2016 describing the frequency of orthognathic intervention on the different cleft phenotypes as the primary outcome. Secondary outcomes included identification of surgical protocol, age of patient at orthognathic intervention, and the method by which patients were evaluated for orthognathic intervention. The rate of orthognathic surgery was 38.1% for bilateral cleft lip and palate (BCLP), 30.2% for unilateral cleft lip and palate (UCLP), 4.4% for isolated cleft palate (ICP), and 1.8% for patients with isolated cleft lip (ICL). 71% (n ¼ 10) reported using lateral cephalograms for orthognathic surgery evaluation and only one of those studies reported specific objective cephalometric measurements for orthognathic intervention. Our findings demonstrated that BCLP possessed the highest rate of orthognathic intervention followed by UCLP, ICP, and ICL. ICP and ICL both possessed low rates of orthognathic intervention. By sharing our findings, the authors hope to provide a useful tool for informing patients' families as to their risk of needing orthognathic intervention.