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East Asia is a major source of dust accounting for 20% of the global dust emission. Work on reconstructing past changes in dust transport in East Asia is complicated by difficulties in distinguishing local sedimentation from aerial material and lack of suitable material for age determination. Here, we address these issues and present a new dust proxy record from Lake Motosu, located on the Pacific side of Japan. The record is anchored by a high‐quality tephra and radiocarbon chronology. Because Lake Motosu is situated in a quartz‐free basaltic volcanic province, all quartz deposited in the lake is likely to be aerially sourced, and variations in quartz content should reflect past changes in dust transport. Our new record detects a low dust deposition event from 3.0 to 2.0 ka. This event corresponds to elevated sea surface temperature in the Sea of Japan and climate conditions similar to a negative phase of the Arctic Oscillation, indicating an association with the weakened Westerlies and with less frequent dust storms in the source region. The increase in spatial resolution of past dust transport reconstructions will further improve our understanding of the mechanism related to dust emission from East Asia. One potential proxy for understanding past changes in atmospheric conditions is aeolian dust. The climate variability links between non‐contiguous geographic regions and strong constraints on geological ages are required to better contribute to the understanding of dust transport. Here, the dust deposition history of the past 8,000 years at Lake Motosu was obtained by quantitative X‐ray diffraction analysis to determine the amount of quartz in the sediments. There is no local source of quartz to Lake Motosu, so we consider that quartz is transported to the lake in the atmosphere. The amount of dust deposition to the Lake Motosu has persistently decreased between 3 and 2 thousand ago. This sustained decrease in dust deposition may be caused by conditions similar to a negative phase of the Arctic Oscillation. This interpretation is consistent with other proxy records from East Asia. Dust deposition history of the past 8 kyr at Lake Motosu was obtained by quantifying quartz amount by X‐ray diffraction analysisReduced amounts of dust accumulation are recognized between 3 and 2 ka, suggesting the Westerlies were away from Lake MotosuClimate conditions similar to a negative phase of the Arctic Oscillation may be the cause of the sustained decrease in dust deposition Dust deposition history of the past 8 kyr at Lake Motosu was obtained by quantifying quartz amount by X‐ray diffraction analysis Reduced amounts of dust accumulation are recognized between 3 and 2 ka, suggesting the Westerlies were away from Lake Motosu Climate conditions similar to a negative phase of the Arctic Oscillation may be the cause of the sustained decrease in dust deposition

Recently, radiocarbon (14C) dating methods using fossil pollen extracted from sediments with a flow cytometer (cell sorter) are under development. Technical limitations experienced by previous studies required extraction of grains <80 μm in diameter. Thus, obtaining a sufficient mass of carbon for dating requires extracting a very large number (∼105) of grains. Another challenge faced by earlier work was preventing contamination by exotic carbon during the extraction process. Here we present a novel solution to this problem by using a cell sorter with a newly designed pretreatment method and an improved extraction method. This enables us to extract large pollen fossils than was previously possible. By using grains, >100 μm in diameter, such as Pinussp., we have reduced the number of grains for required for 14C dating by an order of magnitude, particularly when considering the recent advances in measure ultra-small carbon masses on a single-stage accelerator mass spectrometer at the Atmosphere and Ocean Research Institute, University of Tokyo. We then apply this method to sediments recovered from Lake Motosu, which already has a very robust chronology, to evaluate the new method. Results indicate the method is successful and reveal temporal radiocarbon reservoir effects that appear related to the changes in the depositional environment and/or hydroclimate. The method presented here is widely applicable across multiple environments.

Earthquake hazard assessments for the Tokyo Region are complicated by the trench–trench triple junction where the oceanic Philippine Sea Plate not only underthrusts a continental plate but is also being subducted by the Pacific Plate. Great thrust earthquakes and associated tsunamis are historically recognized hazards from the Continental/Philippine Sea (Sagami Trough) and Continental/Pacific (Japan Trench) plate boundaries but not from the Philippine Sea/Pacific (Izu–Bonin Trench) boundary alone. Here we employed a series of historical and hypothetical rupture models to explain the widespread distribution of geological evidence for an unusually large tsunami found along 50 km of coastline east of Tokyo. Dating to about 1,000 years ago, this inferred tsunami predates local written history by several hundred years. We found that the inland extent of its sand sheet is best explained, in computer simulations, by displacement on one of the three plate boundaries offshore of the Boso Peninsula, which corresponds to the triple junction. The minimum magnitude scenario capable of generating the inland extent of inundation involves displacement along the Philippine Sea/Pacific boundary megathrust. This plate-boundary fault adds another potential source for earthquakes in the Tokyo Region and tsunamis in the Pacific Ocean.

The 2011 Tohoku earthquake, tsunami and resulting damage is often referred to as 3.11 after the date on which it took place. Leading to almost 20 000 people dead or missing, a major nuclear disaster and severe economic damage, 3.11 represents the biggest challenge faced by Japan since the end of World War II. Before 3.11, the possibility of a Mw 9 earthquake in this area was not generally recognized, highlighting the need to reassess seismic risk in NE Japan. The large amount of new quantitative data covering a range of disciplines and from onshore and offshore studies makes 3.11 an important case study that can contribute to improving our understanding of tsunamis, including their formation, their effects on coastal regions and the effectiveness of defensive measures old and new. Geological studies have a key role to play in this new phase of tsunami studies and this is the only method available for determining recurrence intervals over timescales of thousands of years. Data from 3.11 have improved our ability to identify sedimentary records of tsunami events and to estimate tsunami size from geological data. More complete databases will provide invaluable information for long-term planning of coastal regions in convergent plate margins.

In everyday life, people are exposed to radiofrequency (RF) electromagnetic fields (EMFs) with multiple frequencies. To evaluate the possible adverse effects of multifrequency RF EMFs, we performed an experiment in which pregnant rats and their delivered offspring were simultaneously exposed to eight different communication signal EMFs (two of 800 MHz band, two of 2 GHz band, one of 2.4 GHz band, two of 2.5 GHz band and one of 5.2 GHz band). Thirty six pregnant Sprague-Dawley (SD) 10-week-old rats were divided into three groups of 12 rats: one control (sham exposure) group and two experimental (low- and high-level RF EMF exposure) groups. The whole body of the mother rats was exposed to the RF EMFs for 20 h per day from Gestational Day 7 to weaning, and F1offspring rats (46-48 F1 pups per group) were then exposed up to 6 weeks of age also for 20 h per day. The parameters evaluated included the growth, gestational condition and organ weights of the dams; the survival rates, development, growth, physical and functional development, memory function, and reproductive ability of the F1offspring; and the embryotoxicity and teratogenicity in the F2rats. No abnormal findings were observed in the dams or F1offspring exposed to the RF EMFs or to the F2offspring for any of the parameters evaluated. Thus, under the conditions of the present experiment, simultaneous whole-body exposure to eight different communication signal EMFs at frequencies between 800 MHz and 5.2 GHz did not show any adverse effects on pregnancy or on the development of rats.

Reverberation chamber (RC) has been recently developed and used in bio-electromagnetic (EM) field research for investigation of possible adverse health effect of EM waves to human body. Concerning the use of an RC as an exposure device, accurate dosimetry or quantification of EM energy absorbed in exposed animals inside an RC is actually of importance. However, the dosimetry of animals inside an RC is one of challenging problems due to its size and complex behavior of EM fields inside the chamber. This paper is dedicated to the demonstration of three different numerical techniques developed for dosimetry of small animals exposed to EM fields inside an RC at microwave frequencies. First we briefly review procedures of each numerical method and clarify its advantages, disadvantages, and range of applications. Then we demonstrated their validity by either experiments or cross-verification. Finally we discuss the results obtained from each numerical technique.

This study describes the use of a modified “bell-bottom” flap for treatment of partial syndactyly release that may avoid the use of skin grafting.

Due to the difficulty of the specific absorption rate (SAR) measurement in an actual human body for electromagnetic radio-frequency (RF) exposure, in various compliance assessment procedures the incident electric field or power density is being used as a reference level, which should never yield a larger whole-body average SAR than the basic safety limit. The relationship between the reference level and the whole-body average SAR, however, was established mainly based on numerical calculations for highly simplified human modelling dozens of years ago. Its validity is being questioned by the latest calculation results. In verifying the validity of the reference level with respect to the basic SAR limit for RF exposure, it is essential to have a high accuracy of human modelling and numerical code. In this study, we made a detailed error analysis in the whole-body average SAR calculation for the finite-difference time-domain (FDTD) method in conjunction with the perfectly matched layer (PML) absorbing boundaries. We derived a basic rule for the PML employment based on a dielectric sphere and the Mie theory solution. We then attempted to clarify to what extent the whole-body average SAR may reach using an anatomically based Japanese adult model and a scaled child model. The results show that the whole-body average SAR under the ICNIRP reference level exceeds the basic safety limit nearly 30% for the child model both in the resonance frequency and 2 GHz band.

The effects of 1.5 GHz electromagnetic near fields of time division multiple access (TDMA) signal for the Personal Digital Cellular, Japanese cellular telephone standard (PDC) used for cellular phones, on mouse skin carcinogenesis initiated by 7,12-dimethylbenz[a]anthracene (DMBA) were examined. Ten-week-old ICR female mice were treated with a single application of DMBA on shaved dorsal skin by painting at a concentration of 100 μg/100 μl acetone per mouse. One week later, mice were divided into four groups, receiving electromagnetic near fields exposure (DMBA–EMF), sham-exposure (DMBA–Sham), 12-O-tetradecanoylphorbol-13-acetate (TPA, 4 μg /200 μl acetone/mouse), as a positive control (DMBA–TPA), and no-treatment (DMBA–Control). EMF near fields exposure conditions were as follows: skin local peak specific absorption rate (SAR) 2.0 W/kg, whole body average SAR 0.084 W/kg (ratio of peak to average SAR is 24), 90 min a day, 5 days a week, for 19 weeks. At week 20, animals were killed and skin tumors were analyzed histopathologically. The incidences of skin tumors in DMBA–EMF, DMBA–Sham, DMBA–TPA and DMBA–Control groups were 0/48 (0%), 0/48 (0%), 29/30 (96.6%) and 1/30 (3.3%), respectively. Histopathologically, papilloma and squamous cell carcinoma (SCC) were observed in the DMBA–TPA group and only papilloma observed in the DMBA–Control group. The incidences of squamous cell papillomas and squamous cell carcinomas in DMBA–TPA and DMBA–Control groups were 29/30 (96.6%) and 1/30 (3.3%), respectively, numbers of tumors per mouse (tumor multiplicity) being 18.8 ± 13.4 and 0.1 ± 0.5. These data clearly demonstrated that near fields exposure to 1.5 GHz EMF, used for cellular phones, does not exert any enhancing effect on skin tumorigenesis initiated by DMBA.

The ultra-high speed network is the latest trend of the information era that is expected to last a long time. This trend not only requires network development but also promotes the advancement of the related intersection science and technology fields. Further, in a developing information society, it is mandatory for high-speed digital and information techniques to meet a considerable number of new challenges related to Electromagnetic Compatibility (EMC).

Engineering college/university libraries, public libraries, company or corporate libraries, National Technical Information Services (NTIS), or the Defense Technical Information Center (DTIC) are all possible sources for copies of abstracted articles or papers. If the library you visit does not own the source document, the librarian can probably request the material or a copy from another library through interlibrary loan, or for a small fee, you can order it from NTIS or DTIC. Recently it became clear that EMCABs were more timely than publications which were being listed in data files. Therefore, additional information will be included, when available, to assist in obtaining desired articles or papers. Examples are: IEEE, SAE, ISBN, and Library of Congress identification numbers.

Presents 12 abstracts of articles of interest to practitioners and researchers. Engineering college/university libraries, public libraries, company or corporate libraries, National Technical Information Services (NTIS), or the Defense Technical Information Center (DTIC) are all possible sources for copies of abstracted articles or papers. If the library you visit does not own the source document, the librarian can probably request the material or a copy from another library through interlibrary loan, or for a small fee, you can order it from NTIS or DTIC. Recently it became clear that EMCABs were more timely than publications which were being listed in data files. Therefore, additional information will be included, when available, to assist in obtaining desired articles or papers. Examples are: IEEE, SAE, ISBN, and Library of Congress identification numbers.