Cathode reaction on overpack corrosion in the geological repository environments of radioactive waste was identified from corrosion experiments of carbon steel specimens. Carbon steel specimens were encapsulated in degassed glass ampoules with various solutions which were prepared by distilled water degassed by Ar gas bubbling, and set in a thermostatic bath for several weeks. In the X-ray diffraction and X-ray photochemical spectroscopy, crystalline Fe3O4 and Fe2(OH)2CO3, and amorphous Fe(OH)2 were mainly detected on specimens which were immersed into distilled water, high concentration of sodium hydrogen carbonate solution, and low concentration of sodium hydrogen carbonate solution and sodium sulfate solution, respectively. Only hydrogen gas was detected in a gas phase analysis, indicating that hydrogen generation reaction was the dominant cathode reaction in the anoxic condition expected in geological repository environments.

Surface modification is an important part of fabricating nanoparticles with specific properties and functions. We have designed a dipeptide, which we call NS polypeptide, that consists of four asparagine (N) residues and one serine (S) residue, as a molecule for nanoparticle surface modification. Surface modification of magnetic nanoparticles with the NS polypeptide results in reduction of particle-particle and particle-cell interactions. Here, we describe the surface modification and functionalization of bacterial magnetic particles (BacMPs) by spontaneous integration of temporin L conjugated to NS polypeptide. BacMP membranes were modified temporin L. Furthermore, peptide-modified BacMPs showed high dispersibility in aqueous solution compared to unmodified BacMPs. This surface modification technique may represent a new strategy for reducing non-specific binding of nanoparticles to proteins or cells for use in a variety of protein- or cell-associated applications.

We have mapped the nearby face-on spiral galaxy M 33 in the 1.1 mm dust continuum using AzTEC on Atacama Submillimeter Telescope Experiment (ASTE). The preliminary results are presented here. The observed dust has a characteristic temperature of ~ 21 K in the central kpc, radially declining down to ~ 13 K at the edge of the star forming disk. We compare the dust temperatures with KS band flux and star formation tracers. Our results imply that cold dust heating may be driven by long-lived stars even nearby star forming regions.

We collected charcoal fragments during an archaeological excavation at the Tell Ghanem al-Ali site, located on the lowest terrace of the middle Euphrates River, and measured their radiocarbon ages with accelerator mass spectrometry (AMS). Two trenches, Square-1 and Square-2, were dug on the slope of the tell; 8 building levels were detected in the Square-2 trench. In total, 31 charcoal samples were collected from the 2 trenches, and their calibrated ages ranged from 3100–2900 cal BC at the lowest building level to 2400–2050 cal BC at the uppermost layers of the mound, and concentrated in the period 2650–2450 cal BC. The pottery fragments collected on the surface of the mound before the excavation survey was started, as well as those collected from the sediment layers during the excavation, were assigned on the basis of typological sequences to the Early Bronze Age (EB)-III and EB-IV periods. Thus, the concentrated dates (2650–2450 cal BC) obtained by 14C dating are consistent with the age estimated by archaeological contexts. However, the oldest dates of the lowest level (level-7) go back to 3100–2900 cal BC, and these dates may suggest the existence of the human residence prior to the EB period at the site, and may therefore lead to a revision of the oldest age limit of the EB period currently accepted in the region.

Magnetotactic bacteria are a unique species of bacteria, commonly recognized by the presence of magnetic particles within them. These intracellular, nanosized magnetic particles enable the bacteria to migrate and be manipulated by magnetic force. To date, magnetotactic bacteria have been widely researched and implemented in various biotechnology based applications. In this study, as an extension to its applications, the magnetotactic bacterium, Magnetospirillum magneticum AMB-1, was applied in the microbial recovery of gold from plating waste. M. magneticum AMB-1 successfully precipitated approximately 42% and 100% of gold from growth medium containing 10 μM gold and from a mixture of plating waste/growth medium containing 0.4 μM gold, respectively. These observations and results strongly suggests that an important advancement in biorecovery of rare metals and bioremediation of toxic metals was achieved in which the application of whole cell bacteria, and direct precipitation of metals from plating waste using magnetotactic bacteria was performed for the first time.

In the diagnosis, treatment, and care of dementia patients in the senile stage, comprehensive evaluation of ability in daily life and mental function is needed. Using a simple behavioral rating scale for the mental states (NM scale) and activities of daily living (N-ADL) of the elderly, we evaluated 250 elderly subjects. According to the NM scale, the scores for subjects in whom the severity was clinically diagnosed were as follows: normal, 50–48; borderline, 47–43; mild dementia, 42–31; moderate dementia, 30–17; and severe dementia, 16–0. Screening for dementia and determining its severity were readily accomplished using the NM scale, and basic activities in the daily life of the elderly could be evaluated effectively using the N-ADL. There was a significant correlation (r=0.863) between the Hasegawa dementia scale and the NM scale (p<0.001), a significant correlation (r=−0.947) between intellectual function scores of the GBS scale and the NM scale, and a significant correlation (r=0.944) between motor function score of the GBS scale and the N-ADL score. Evaluations of daily life activities can be made not only by psychiatrists and clinical psychologists, but by nonspecialists as well, because they are based on data obtained by observation of daily life behaviors; thus, assessment is appropriate both in clinical settings and in places of living.

The impact of the unusually severe drought associated with the 1997–1998 El Niño on tropical forest dynamics in Sarawak, Malaysia was examined. Mortality during the non-drought period (1993–1997) in a core plot (1.38 ha) was 0.89 % y−1, while that during the drought period (1997–1998) in the same plot and a peripheral plot was 6.37 and 4.35 % y−1, respectively. The basal area lost in the drought interval was 3.4 times that of the annual incremental basal area in 1993–1997. Drought mortality was higher for the smaller trees, though it was less size dependent than the non-drought mortality. Dipterocarpaceae, which is the dominant family in the study plot, had a mortality 12–30 times higher in the drought than the non-drought period. There were no significant differences in mortality among the topographic types. From the results of a log-linear model (multi-factored contingency table), the death of trees was correlated with size class, indicating a change in the size-class structure of the forest. Thus, both the species composition and structure are totally affected by such an episodic drought even in a per-humid tropical forest.

A conductivity difference in a PZT film in a Pt/PZT/Pt capacitor was found by novel charged-up SIMS analyses for the first time. The charged-up SIMS technique was useful for evaluating the conductivity profile in the PZT film. It was found that the conductive region existed in an as-prepared PZT film near the bottom Pt electrode. After hydrogen plasma treatment at 45°C, the conductive region increased in the PZT film near the top electrode. Electrical measurements showed that the leakage current of the capacitor increased after hydrogen treatment. The hydrogen was expected to reduce PZT both at grain boundaries and the electrode-PZT interfaces, and to form the conductive region, which induced an increase in leakage current.

The surface passivation of GaAs power FET has been investigated. Intermodulation distortion of GaAs power FET was found to be affected by frequency dispersion which originates from electron trap at the surface in the vicinity of the gate. There are two ways to suppress the frequency dispersion. One is reducing electron trap itself by using surface passivation, the other is making surface insensitive to the surface trapping effect. We found the FET with undoped InGaP layers on the n-GaAs channel is free from surface trapping effects. The undoped InGaP layer acts as an ideal passivation layer for the channel, since it shows only 2% frequency dispersion of drain current at 1MHz compared to DC condition.

Methyl siloxane spin-on-glass (SOG) is a conventional gap-filling material. In accordance with the requirement of low permittivity, many of major SOG suppliers are developing new types of methyl siloxane SOGs.

The most interesting property of these SOGs is their permittivity, which we measured by making stack structures of Al-0.5%Cu / TEOS CVD SiO2 / SOG / n+ Si. We also studied I-V characteristics, refractive indices, FT-IR spectra, stress, and moisture resistance.

All of the SOGs showed small stress and fair moisture resistance. Leakage currents were less than 2.5E-10 A/cm2 for bias voltages up to 5V. Permittivities ranged from 2.9 to 3.6. We observed a correlation between permittivity and FT-IR spectral features associated with Si-O-Si bonds. Reducing the number density of Si-O-Si bonds may be an effective way to lower the permittivity of this class of SOGs

As device geometries and operating voltage continue to scale while functional density increases, it is imperative to reduce the RC time delay. The replacement of Si0 2 as an intermetal dielectric with an insulator of lower dielectric constant is a particularly attractive solution since it provides immediate performance improvement through reduction in capacitance. An embedded polymer integration scheme improves the interconnect performance through line-to-line capacitance reduction by using polymer only between tightly spaced lines. The gapfill polymeric materials do not degrade the electromigration performance of standard multilayered TiN/Al/TiN interconnects. Embedded polymers alleviate many of the integration and reliability problems associated with polymer integration, and can be easily adopted into a standard production process.