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Electrostatic discharge (ESD) has been known to cause electromagnetic noise against electronic equipment and devices even before the technical concept of electromagnetic compatibility (EMC) was established 68 years ago in the United States and 48 years ago in Japan, while the ESD still continues to be studied as one of the most significant issues that should be solved in EMC areas. This is largely because the underlying nature of ESD has yet to be essentially elucidated from an EMC perspective. On the other hand, as an academic research organization on EMC in Japan, a Technical Committee named ‘EMCJ’ on ‘Environmental Electromagnetic Engineering’ was founded in 1976 in both the Institute of Electrical Engineers of Japan (IEEJ) and the Institute of Electronics and Communication Engineers or the present IEICE (Institute of Electronics, Information and Communication Engineers) to address EMC concerns. Since then, the EMCJ has been jointly conducting EMC research activities under the IEICE as the nominating body and the IEEJ as the associative body, whereas the EMCJ of IEEJ was dissolved in 1999 to form a new Technical Committee on EMC (TC‐EMC) in order to deal with EMC issues appropriate to the IEEJ. In this review, to mark the 25th anniversary of the IEEJ Technical Committee on EMC (TC‐EMC) in 2024, the EMC research efforts and activities that the TC‐EMC has conducted over the past 25 years from January 2000 to March 2024 are surveyed from 1272 technical papers presented at the technical meetings. Furthermore, among the ESD issues identified in these technical papers, the latest case studies utilizing ‘spark resistance laws’ that allow the analysis of the initial behavior of sparks, in which a spark is the essence of ESD and is the key to open the door to elucidate the phenomenon, particularly from an EMC perspective, are reviewed. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Abstract We present stratigraphic, geochemical (CNS elemental analysis), and micropaleontological (ostracode assemblages) evidence for the 2011 Tohoku-oki tsunami impact in Matsushima Bay, northeastern Japan, and examine the recovery process after the impact to the bay environment using short sediment cores from two different topographic settings at a water depth of approximately 4 m. At both sites, tsunami deposits are composed of two sedimentary layers that recorded the first tsunami run-up and backwash. At the western site near the channel that connects the bay with the Pacific Ocean, the first tsunami wave eroded the bay floor sediments and left the tsunami deposits composed of medium sand rich in shell fragments, but with sparse numbers of meiobenthic ostracodes. By contrast, at the eastern site, which is surrounded by many small islands, the first wave eroded very little of the bay floor sediments and left tsunami deposits consisting of sandy mud, rich in exotic ostracodes, such as phytal species, shallow marine sand dwelling species, and brackish water species. Overlying post-tsunami deposits are composed mainly of organic-rich mud in which organic matter was derived primarily from marine plankton. Ostracode assemblages in the tsunami deposits lack the offshore species that live in water depths >50 m and are dominated by the species from Matsushima Bay and its adjacent nearshore, upper sublittoral areas, and brackish water environments. The distance from deep-water offshore areas to the core sites is too far to transport ostracode valves by tsunami waves. Highlights • The larger first tsunami wave was the main source of the tsunami deposit. • Ostracode assemblages in the tsunami deposits lack the offshore species. • Ostracode assemblages had not yet recovered from the 2011 tsunami impact. • The post-tsunami deposit contained organic-rich muds attributed to marine planktons. [ABSTRACT FROM AUTHOR]

We reconstructed recurrent coseismic subsidence during the middle Holocene from analyses of sedimentary facies and fossil diatom assemblages in a small drowned valley, the Shinjo lowland, bordering Lake Hamana, near the Nankai–Suruga trough, central Japan. The Lake Hamana region is known for coseismic subsidence during the 1707 Hoei (M8.6) and 1854 Ansei-Tokai (M8.4) earthquakes along the Nankai–Suruga trough subduction zone. A coring survey revealed three widely distributed peat layers in the lowland, with a mud layer overlying each of the two lower peats with a sharp contact. We traced the alternating peat–mud beds for over 300 m along the long axis of a valley. The fossil diatom assemblage analysis revealed that the peat layers were deposited in a freshwater pond/marsh environment, which changed abruptly to an estuarine to inner bay environment, recorded by the mud layers. From the sudden environmental change at the two peat–mud contacts and our radiocarbon dating results, we inferred that coseismic subsidence followed by an invasion of seawater into the lowland occurred at least twice, during a great earthquake that occurred between 5645 and 6635 cal yr BP and during another great earthquake at ca. 5700 cal yr BP. Within the mud layers, the dominant diatom species changed gradually upward from Nitzschia frustulum and Cocconeis scutellum in the lower part to Cyclotella striata and Achnanthes submarina in the upper part. These changes suggest that water depth and salinity gradually increased after the coseismic subsidence. A possible cause of this gradual subsidence is postseismic subsidence following great Nankai-Suruga trough earthquakes. [ABSTRACT FROM AUTHOR]

The Nankai-Suruga Trough, the subduction zone that lies immediately south of Japan's densely populated southern coastline, generates devastating great earthquakes (magnitude > 8) characterised by intense shaking, crustal deformation and tsunami generation. Forecasting the hazards associated with future earthquakes along this > 700 km long fault requires a comprehensive understanding of past fault behaviour. While the region benefits from a long and detailed historical record, palaeoseismology has the potential to provide a longer-term perspective and additional crucial insights. In this paper, we summarise the current state of knowledge regarding geological evidence for past earthquakes and tsunamis along the Nankai-Suruga Trough. Incorporating literature originally published in both Japanese and English and enhancing available results with new age modelling approaches, we summarise and critically evaluate evidence from a wide variety of sources. Palaeoseismic evidence includes uplifted marine terraces and biota, marine and lacustrine turbidites, liquefaction features, subsided marshes and tsunami deposits in coastal lakes and lowlands. While 75 publications describe proposed evidence from > 70 sites, only a limited number provide compelling, well-dated evidence. The best available records enable us to map the most likely rupture zones of twelve earthquakes that occurred during the historical period. This spatiotemporal compilation suggests that the 1707 CE earthquake ruptured almost the full length of the subduction zone and that earthquakes in 1361 CE and 684 CE may have been predecessors of similar magnitude. Intervening earthquakes were of lesser magnitude, highlighting the variability in rupture mode that characterises the Nankai-Suruga Trough. Intervals between ruptures of the same seismic segment range from < 100 to > 450 years during the historical period. Over longer timescales, palaeoseismic evidence suggests intervals between earthquakes ranging from 100 to 700 years, however these figures reflect a range of thresholds controlling the creation and preservation of evidence at any given site as well as the genuine intervals between earthquakes. At present, there is no geological data that suggest the occurrence of a larger magnitude earthquake than that experienced in 1707 CE, however few studies have sought to establish the relative magnitudes of different earthquake and tsunami events along the Nankai-Suruga Trough. Alongside the lack of research designed to quantify the maximum magnitude of past earthquakes, we emphasise issues over alternative hypotheses for proposed palaeoseismic evidence, the paucity of robust chronological frameworks and insufficient appreciation of changing thresholds of evidence creation and preservation over time as key issues that must be addressed by future research. [ABSTRACT FROM AUTHOR]

During the last 1500 years, a marsh on the north coast of Suruga Bay, central Japan, has experienced as many as five rapid submergence events. This conclusion is supported by analyses of depositional facies and pollen and diatom assemblages in sediment cores from the Ukishimagahara lowland, on the footwall side of the Fujikawa-kako fault zone (FKZ), the northern extension of the Nankai and Suruga Troughs. Light-colored silt or clay beds, ∼30–50 cm thick, deposited as the result of submergence events that drowned the marshland, cover terrestrial peat or humic soils produced by the marshland vegetation. Radiocarbon ages and dated tephras suggest that in this lowland submergence events have occurred at aperiodic intervals of 100–400 years. Atmospheric phenomena can cause increased precipitation and flooding by rivers and typhoons, but they cannot explain the cyclic submergence events at centennial timescales. During the late Holocene, sea levels have been declining relative to land around the Japanese Islands, so high sea levels cannot explain the periodic submergence of the lowland. The most likely cause of these events, therefore, is coseismic subsidence of the lowland related to great earthquakes (∼M8.0) occurring in the FKZ or the Suruga Trough. Coseismic coastal deformation around the study area during the 1854 Ansei Tokai earthquake supports this hypothesis. [ABSTRACT FROM AUTHOR]

Re-analysis of the lithological, paleontological, and geochemical data of three lagoonal sediment cores reveal the tsunami overwash history from 8000 to 6500 cal BP along the northern Suruga Bay coast, facing the eastern Nankai Trough. The coring sites are located in a transcect 0.8, 1.5, and 1.7 km inland, respectively, from the coastline at the time the overwash events occurred. The washover sand beds are distinguished from the lagoonal muds by the presence of quartz and mica, which are abundant on the outer (marine) side of the lagoon, as well as marine shell fossils. The increased C/S ratio often associated with sand beds, reflects input of open seawater to the reductive lagoon, and supports this interpretation. A maximum of eight tsunami deposits were identified between ∼7800 and 6500 cal BP, many of which can be correlated between the three cores. The magnitude of tsunami overwash implied by the thickness and grain size of tsunami deposits, and increase of C/S ratio following their deposition is relatively large at ∼7500-7200 cal BP during the post-glacial sea level rise and decreases with time during the subsequent high sea level stand. This occurrence mode (timing and scale of formation) of tsunami washover is explained by temporal changes in coastal geomorphology, rather than differences in the magnitude of individual tsunamis. Around 7500-7200 cal BP, sea level rise equilibrated with or exceeded the growth of the bay mouth barrier, and tsunamis could easily cross the small barrier and enter the lagoon, leaving behind thick and coarse-grained deposits. As the barrier becomes larger during the subsequent sea-level highstand, only the highest-amplitude waves exceeded the height of the barrier. By ∼6500 years ago, the barrier was high enough to prevent tsunamis from entering the lagoon. Similarly, the occurrence mode of tsunami deposits reported along the coast of Suruga Bay and Enshu-nada over the past 6000 years can be explained in relation to the growth of coastal barriers. • A 8000 year-history of ttsunami overwash in the eastern Nankai Trough region. • Degree of coastal barrier development controlled the magnitude of tsunami overwash. • Large tsunami deposits tend to form during the periods of sea level rise. • No giant tsunamis, far exceeding the historical events, occurred in this period. [ABSTRACT FROM AUTHOR]

This article describes the bedforms formed by the 2011 Tohoku-Oki tsunami on the southern Sendai Plain, NE Japan. Integrated analyses of satellite images, field survey data, and X-ray radiographs revealed the natural shapes of these bedforms. The dominant bedforms are dunes and antidunes about ~ 20 cm thick (high) and relatively flat because of their meter-scale wavelengths. Their morphologies reflect mainly the tsunami run-up flow on the flat lowland and the return flow in a narrow, steep valley. Flow depth changed at sites where the level of the ground surface changed along the tsunami flow path, causing the flow velocity to fluctuate. Flow velocity decreased in depressed (deep-water) sections and increased in raised (shallow-water) sections. The types and positions of the tsunami deposit bedforms were thus strongly controlled by local ground surface roughness, such as raised roadbeds and levees. As a result, the observed thickness distribution of the tsunami deposits fluctuates. It is important to consider the possible existence of bedforms in paleotsunami surveys, especially for accurate determination of the thickness distribution of the tsunami deposits, because thickness data are essential information for reconstruction of the tsunami inundation limit as well as its flow speed. [ABSTRACT FROM AUTHOR]

Three washover sand beds, ranging from 15 to 34 cm in thickness, were recorded in a lagoonal mud sequence on the Shizuoka coast of central Japan, which faces the Suruga Trough. The sand beds were composed of well-sorted and well-rounded beach sand derived by a marine inundation. The basal erosion surface, mud clasts, and presence of both inverse and normal grading suggest that the sand beds formed as a result of high-energy deposition. The sand beds are multilayered, with fine alternations of sand sheets and mud drapes, which are consistent with deposition from a long-period wave train. Radiocarbon dates obtained from the three washover deposits are around ad 1000, 3565–3486 cal. yr BP, and 4000 cal. yr BP. Vertical changes in the diatom assemblages suggest a gradually increasing inflow of seawater up to the second sand bed, followed by a rapid change to freshwater conditions just above the bed. The gradual increase of seawater inflow begins again just above the second sand bed. We conclude that this series of sequential environmental changes indicates interseismic subsidence and coseismic uplift. The study area experienced around 1 m of uplift during the ad 1854 Ansei Tokai earthquake (Mw 8.4). In contrast, the area has subsided gradually (c. 6 mm/yr) during the present interseismic period. The youngest sand bed may be correlated with the ad 1096 Eicho earthquake, which caused severe damage along the Shizuoka coast. [ABSTRACT FROM AUTHOR]

Abstract: The AD 1498 Meio earthquake (M8.2∼8.4) that occurred along the eastern Nankai trough, and the tsunami generated by the earthquake, induced major geomorphological and social changes along the Pacific coast of central Japan. Geological coring along the palaeochannel of the Hamana River, southern Shizuoka Prefecture, revealed that its river mouth was abruptly closed followed by a rapid change from river to marsh environment at the end of the 15th century. It is suggested that mass transport of sediments by the Meio tsunami forced the closure of the river mouth. The latter environmental change happened synchronously with the sudden decline of a famous port town, Hashimoto, formerly flourishing along the middle reach of Hamana River. Closure of the water route connecting Hashimoto with the Pacific Ocean potentially led to the decline and abandonment of the port town. [Copyright &y& Elsevier]

The International Electrotechnical Commission (IEC) has prescribed an immunity test (IEC61000-4-2) of electronic equipment against electrostatic discharges (ESDs), in which a discharge current to be injected onto equipment under test is specified. As for the waveform, however, not the whole waveform but only the rise time, the first peak, and the current amplitudes at 30 and 60 ns are given in the time domain together with their uncertainties, which are required to check on the condition that an ESD generator (ESD-gun) shall be arranged vertically to an IEC-recommended calibration target and its earth return wire is kept away as far as possible from a vertical ground plane (IEC standard arrangement). In this study, to clarify how arrangements of an ESD-gun and its earth return wire affect discharge currents, we measured discharge current waveforms for contact discharges of an ESD-gun onto an IEC calibration target with respect to various inclinations of the ESD-gun and arrangements of its earth return wire, and also calculated their current power spectra normalized to that of the discharge current for the IEC standard arrangement. As a result, we found that inclinations of the ESD gun affect the first peak current, which increases current power spectra by 14 dB at frequencies over 300 MHz, and that arrangements of the return wire influence the current waveforms between the first and second peaks, which provides variations in power spectra by ±12 dB in the frequency range from 10 MHz to 200 MHz. This finding suggests that arrangements of an ESD-gun and its earth return wire are likely to cause different immunity test results. It was also found that in comparison with measured discharge currents for the standard arrangement, the calculated waveform of a discharge current from a formula, which has been included in the recent standard, has a more gentle falling waveform, and produces power spectra of +15 dB in the frequency range from 10 MHz to 200 MHz and -12 dB at frequencies over 300 MHz. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(1): 9-14, 2012; Published online in Wiley Online Library (). DOI 10.1002/eej.21270 [ABSTRACT FROM AUTHOR]

A flight of Holocene marine terraces on the southwestern coast of Cape Omaezaki of central Japan provides evidence of recurrent millennium-scale uplift events. We reconstructed the uplift history of these terraces by using facies analysis of drill core and geoslicer samples, environmental analysis of trace fossils, and 14C age determinations. Coastal uplift can be identified by the displacement of beach deposits such as foreshore deposits, which represent the intertidal swash zone of a wave-dominated sandy coast. Three levels of former beach deposits facing the Nankai Trough were identified near the coast in the Omaezaki area. The highest of these, dated at about 3020–2880 BC, records a maximum of 2.2–2.7 m of emergence. The middle beach surface, of minimum age 370–190 BC, shows 1.6–2.8 m of emergence. The lowest beach surface, which is older than 1300–1370 AD, records 0.4–1.6 m of emergence. Our analysis of vertical crustal deformation data during the Holocene in this region suggests that rapid and strong uplift was restricted to the southwestern coast of the Omaezaki area and was probably caused by high-angle thrusting on subsidiary faults branching from the underlying plate boundary megathrust. [ABSTRACT FROM AUTHOR]

Foraminiferal tests are commonly found in tsunami deposits and provide evidence of transport of sea floor sediments, sometimes from source areas more than 100 m deep and several kilometers away. These data contribute to estimates of the physical properties of tsunami waves, such as their amplitude and period. The tractive force of tsunami waves is inversely proportional to the water depth at sediment source areas, whereas the horizontal sediment transport distance by tsunami waves is proportional to the wave period and amplitude. We derived formulas for the amplitudes and periods of tsunami waves as functions of water depth at the sediment source area and sediment transport distance based on foraminiferal assemblages in tsunami deposits. We applied these formulas to derive wave amplitudes and periods from data on tsunami deposits in previous studies. For some examples, estimated wave parameters were reasonable matches for the actual tsunamis, although other cases had improbably large values. Such inconsistencies probably reflect: (i) local amplification of tsunami waves by submarine topography, such as submarine canyons; and (ii) errors in estimated water depth at the sediment source area and sediment transport distance, which mainly derive from insufficient identification of foraminiferal tests. [ABSTRACT FROM AUTHOR]

This study proposes an equation for estimating whole body average specific absorption rate (WBSAR) in human body models for plane-wave exposure at whole-body resonance frequency. This study is important because the WBSAR takes maximal at this frequency and approaches the basic restrictions in the international guidelines/standards for human protection. Therefore, the variability of the WBSAR at this frequency has attracted a great deal of attention. First, the dominant factors influencing the resonance frequency of the human body models are investigated for plane-wave exposures. An equation for estimating the WBSAR at the resonance frequency is then proposed based on an analogy to an antenna. This equation can estimate the WBSAR with the body mass index of the human body only for a given incident power density. The uncertainty of the WBSAR estimated with the proposed equation is approximately 10%, which is mainly attributed to the electrical constants of tissue, including the in homogeneity of the human body model. The variability of the WBSAR due to the body shape was found to be 30% for humans of the same age. [ABSTRACT FROM AUTHOR]

Four sand units deposited by tsunamis and one sand unit deposited by storm surge(s) were identified in a muddy marsh succession in a narrow coastal lowland along the Pacific coast of central Japan. Tsunamis inad 1498, 1605, 1707 and 1854 that were related to large subduction-zone earthquakes along the Nankai Trough, and storm surges in 1680 and/or 1699 were responsible for the deposition of these sand units. These sand units are distinguished by lithofacies, sedimentary structures, grain-size and mineral composition, and radiocarbon ages; their ages are supported by events in local historical records. The tsunami deposits in the study area are massive or parallel-laminated sands, with associated intraclasts, gravels, draping mud layers and, rarely, a return-flow subunit. The storm surge deposits are devoid of these characteristics, and are composed of groups of thin, current ripple-laminated sand layers. The differences in sedimentary structures between the tsunami and storm surge deposits are attributed to the different characteristics of tsunami and storm waves. [ABSTRACT FROM AUTHOR]

For investigation of possible bio-effects of the 2-GHz wideband code division multiple access cellular system on pregnant and newborn rats, we have developed an unrestrained whole-body exposure setup, which employs two dipole antennas to induce a circularly polarized field at the location of the rats. The dosimetric results, by using the finite-difference time-domain method in conjunction with anatomical rat models, have confirmed the realization of a circular polarization in the exposure space, and have also revealed that the exposure setup can maintain a relative variation of the whole-body average specific absorption rate (SAR) within ±60% of the designed average level for various positions of rats. These findings show that the exposure setup is reasonable and acceptable in view of the actual SAR variation in a human body due to RF exposure from base stations. [ABSTRACT FROM AUTHOR]

Abstract: This study proposes a tsunami depositional model based on observations of emerged Holocene tsunami deposits in outcrops located in eastern Japan. The model is also applicable to the identification of other deposits, such as those laid down by storms. The tsunami deposits described were formed in a small bay of 10–20-m water depth, and are mainly composed of sand and gravel. They show various sedimentary structures, including hummocky cross-stratification (HCS) and inverse and normal grading. Although, individually, the sedimentary structures are similar to those commonly found in storm deposits, the combination of vertical stacking in the tsunami deposits makes a unique pattern. This vertical stacking of internal structures is due to the waveform of the source tsunamis, reflecting: 1) extremely long wavelengths and wave period, and 2) temporal changes of wave sizes from the beginning to end of the tsunamis. The tsunami deposits display many sub-layers with scoured and graded structures. Each sub-layer, especially in sandy facies, is characterized by HCS and inverse and normal grading that are the result of deposition from prolonged high-energy sediment flows. The vertical stack of sub-layers shows incremental deposition from the repeated sediment flows. Mud drapes cover the sub-layers and indicate the existence of flow-velocity stagnant stages between each sediment flow. Current reversals within the sub-layers indicate the repeated occurrence of the up- and return-flows. The tsunami deposits are vertically divided into four depositional units, Tna to Tnd in ascending order, reflecting the temporal change of wave sizes in the tsunami wave trains. Unit Tna is relatively fine-grained and indicative of small tsunami waves during the early stage of the tsunami. Unit Tnb is a protruding coarse-grained and thickest-stratified division and is the result of a relatively large wave group during the middle stage of the tsunami. Unit Tnc is a fine alternation of thin sand sheets and mud drapes, deposited from waning waves during the later stage of the tsunami. Unit Tnd is deposited during the final stage of the tsunami and is composed mainly of suspension fallout. Cyclic build up of these sub-layers and depositional units cannot be explained by storm waves with short wave periods of several to ten seconds common in small bays. [Copyright &y& Elsevier]

An immunity testing method for electrostatic discharge (ESD) is being specified in IEC 61000-4-2, in which the contact discharge of an ESD gun is being normally specified. Air discharge testing is known to be a severe immunity test compared to contact discharge testing, while the discharge current injected is not well reproduced. Grasping the behavior of the current injected by the air discharge would be helpful in establishing the worst-case ESD immunity testing. We previously measured the discharge currents for air discharge testing onto the IEC-recommended current transducer with a commercially available ESD gun, and showed that there exists a specific relationship of Ip·trξ/Vc=constant (ξ=0.75), between rise time tr and current peak Ip. The current transducer, however, has a frequency-dependent transfer impedance which should affect the measured current waveform. In this study, we investigated whether the above-mentioned specific relationship can be obtained for air discharge of an ESD gun onto a ground that assumes a metal enclosure of electronic equipment under test. A method was presented for estimating the discharge current from simultaneously measured magnetic fields with two magnetic field probes regardless of the distance between the gun discharge-point and the probe position. This method was validated for contact discharge of an ESD gun to an SMA connector. With this method, we estimated the discharge currents injected onto a ground for air discharge testing of an ESD gun with intentionally fast and slow approaches. As a result, we could confirm a specific relationship between rise time tr and current peak Ip of Ip·trξ/Vc=constant with ξ=0.57 independent of charge voltages and gun approaches. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 158(4): 51– 59, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20454 [ABSTRACT FROM AUTHOR]

This paper discusses the correlation between peak spatial-average specific absorption rate (SAR) and maximum temperature increase for antennas attached to the human trunk. Frequency bands considered are 150, 400, and 900 MHz, which are assigned for occupational communications. This problem is throughly investigated with the aid of Green's function. In particular, the effect of variation of thermal constants on the temperature increase is revealed by using one-dimensional model. Computational results suggests that one of the most dominant factors which affect the correlation between peak SAR and maximum temperature increase is blood flow in tissues. This is confirmed by considering a three-dimensional realistic human body model. Uncertainties caused by the calculation of peak SAR and the difference in the body model shape are also quantified. [ABSTRACT FROM AUTHOR]

In electromagnetic dosimetry of children heads for mobile telephones, the dielectric properties of biological tissues for adults are so far being used due to the lack of the ones of children. In this paper, we derived an empirical formula according to Lichtenecker's exponential law for the complex permittivity of various tissues as a function of the hydrated rate or the total body water (TBW). We first examined its validity using the data measured by Peyman et al. for rats, and then applied the formula to the dielectric properties of 7-year-old and 3-year-old child head models by means of the relationship between the TBW and the age. With the dielectric properties for children derived in such an approach, we analyzed numerically the spatial peak specific absorption rate (SAR) for a 900-MHz mobile telephone in adult and child head models. As a result, we found that the dielectric properties for children do not affect significantly the 1- or 10- g averaged spatial peak SAR as well as the penetration depth. The finding could be qualitatively explained as cancellation of the increased conductivity and decreased electric field penetrating into the tissue because of the same degree of increase between the conductivity and permittivity in children compared to adults. Even in an extreme case, the age effect on the spatial peak SAR of dielectric properties is still within 10%. [ABSTRACT FROM AUTHOR]

Abstract: The burial history of the Isumi River lowland was reconstructed based on a facies analysis of borehole and geoslicer samples, undisturbed sediment samples collected by 4.0-m-long, 0.35-m-wide, and 0.01- to 0.05-m-deep wedge-shaped steel case, together with an analysis of molluscan shell assemblages for environmental assessment and 14C age measurements. The borehole successions constitute a part of a depositional sequence in a fluvial- and wave-dominated incised valley. The facies succession and age data suggest that the lower part of the succession (before 7.0 calendar kilo years before present (cal. ky BP)) has, in a broad scale, an aggradational to retrogradational stacking pattern, although a short period of sediment progradation occurred during 9.0–8.5 cal. ky BP. The upper part (7.0 cal. ky BP–present) is a prograding succession of beach-shoreface and bayhead delta sediments deposited in an enclosed bay environment (ca. 3.5 cal. ky BP). The facies changes from an open to an enclosed marine environment resulted from barrier formation. Age measurements indicate that the Choja and Izumi terrace surfaces formed some time after 6.5 cal. ky BP and around 3.5 cal. ky BP, respectively. The temporary progradation during 9.0–8.5 cal. ky BP was probably associated with several meters of tectonic uplift, which resulted in an increase in the sediment supply owing to intensified fluvial and marine erosion. After a tectonic uplift at about 6.4 ky BP, a wide strand plain started to form along the bay shore as a result of sediment transport from both north and south of the bay by longshore currents. However, a barrier developed about 3.5 cal. ky BP, after the Izumi Surface was uplifted. Subsequently, this uplift transported sediments probably bypassed the southern part of the lowland and accumulated near the mouth of the bay to form this barrier, as is indicated by the poor strand plain development after this time. Strand-plain progradation might have been prevented by strong wave influences from the Pacific Ocean and longshore currents, resulting from both the recession of the sea cliffs south and north of the lowland and from the uplift, which shifted the shoreline seaward and changed the shoreline environment from an enclosed bay into a more open marine environment. [Copyright &y& Elsevier]

In this paper, high-frequency (HF) and microwave electromagnetic (EM) fields in experimental fusion facilities were statistically measured, and the exposure levels were compared with safety guidelines to ensure workers' safety. Since leaked EM fields have time-varying characteristics whose amplitudes vary according to a stochastic process, a measurement of their amplitude probability distribution (APD) was conducted. An approach was then presented to derive from the measured APD the specific absorption rate (SAR) in an exposed human body. The statistically-averaged whole-body-averaged SAR showed that the leaked field intensities were low enough to not cause any thermal hazards for the workers in the specific EM environment. The statistically averaged SAR also showed fair agreement with the SAR derived from the time average over 6 mm as specified in the safety guidelines. This finding suggests the usefulness of the APD measurement in lieu of a field measurement over a 6-mm period because the APD can be obtained in a time period much less than 6 mm. [ABSTRACT FROM AUTHOR]

An ESD (electrostatic discharge) testing is specified in the IEC 61000-4-2, in which the detailed waveform of the discharge current injected by an ESD gun is prescribed. However, due to lack of understanding of the discharge process, it is difficult to confirm whether or not the IEC current waveform can be injected onto actual equipment. We thus previously proposed an equivalent circuit model for the ESD gun based on its geometrical structure, and showed decisive factors for the discharge current. In this study, in order to confirm the feasibility of the above equivalent circuit model, we measured with a 6-GHz wide-band digital oscilloscope the discharge current through an SMA connector and the resultant magnetic near field for the contact discharge of an ESD gun. As a result, we found that both measured waveforms approximately agree with those calculated from our equivalent circuit model. We then measured with respect to charge voltages the magnetic near fields for the contact discharge of the ESD gun to the ground, which revealed that the measured waveform around the first peak is in fair agreement with the calculated one. Furthermore, we found that the magnetic field peak increases with increasing charge voltage, whose dependence can be predicted from our equivalent model. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(1): 17–24, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20194 [ABSTRACT FROM AUTHOR]

The frequency at the peak of electromagnetic radiation from a PCB (Printed Circuit Board) as a result of ground bounce is considered predictable from the frequency characteristics of the input impedance between the power supply and ground layer (below called the PCB impedance). However, the relationship is largely unknown. In this paper, the electromagnetic radiation of the PCB and the frequency spectrum of the PCB impedance are analyzed by the FDTD (Finite-Difference Time-Domain) method and their relational mechanism is studied by comparison with the measured values. It is found that the peak of the electromagnetic radiation appears at the frequency where the PCB is a minimum if the PCB is excited by a voltage source with an internal resistance sufficiently smaller than the PCB impedance, and that this peak is shifted toward the frequency at which the PCB impedance becomes a maximum if the internal resistance is increased. The radiation power ratio derived from the resistive components (called the resonant resistances) at two frequencies where the PCB impedance is maximum and minimum (resonant frequencies) mostly agrees with the ratio of the squares of the radiated electric field. Hence, the radiation peak frequencies of the PCB are determined both by the internal resistance of the excitation source and the resonant resistance of the PCB impedance. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(11): 30–38, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10209 [ABSTRACT FROM AUTHOR]

The transient electromagnetic (EM) fields caused by an electrostatic discharge (ESD) have broadband frequency spectra, which cause serious failure to high-tech information equipment. From this perspective, ESD testing for the EM immunity of the equipment is specified by IEC 61000-4-2, in which the detailed waveform of the discharge current injected onto the IEC recommended Pellegrini target in contact with an ESD-gun is prescribed for calibration. However, the factors for determining the current waveform remain unclear, and thus the IEC prescribed current waveform is unlikely to be injected into actual equipment. In this study, based on the structure of an ESD-gun, an equivalent circuit modeling is proposed for analyzing the discharge current injected onto a 50-Ω SMA connector instead of the IEC target that has frequency-dependent transmission characteristics. Its validity is confirmed by comparing the calculated current waveform with the measured result. The proposed circuit modeling is also validated from measurement of the discharge current injected onto a transmission line by the ESD-gun. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 149(1): 8–14, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10367 [ABSTRACT FROM AUTHOR]

Investigates the human-body effect on the peak specific absorption rate (SAR) in the human head for portable telephones. Use of parallel finite-difference time-domain computation system on Linux-based personal computers; Finding of a difference in the averaged spatial peak SAR and a difference in the SAR in the brain and eyes compared to the isolated head model; Slight decrease in the SAR due to the body effect.

In a discharge between charged metal spheres, the effect of the metal spheres on the generated electromagnetic field has not been clearly indicated. One of the authors (Fujiwara) has proposed the following computation method (called the image dipole method) for a spark discharge between metal spheres. The surface of the metal sphere is replaced by an infinite number of image charge pairs, which are arranged so that the surface is kept at the same potential. Then, the generated electromagnetic field is calculated analytically by superposition of the dipole fields caused by the spark current derived from the Rompe-Weizel spark-resistance law. It has been shown by the analysis that the metal sphere increases the field level. Then, the electromagnetic field generated by the spark discharge between metal spheres is calculated numerically by the finite-difference time-domain (FDTD) method, with the spark current as an excitation source for the metal sphere. The validity of the approach has been shown through comparison to the analytic solution by the image dipole method for the magnetic field waveform. However, the above computation method has the problem that the static electric field before the onset of the discharge cannot be calculated, which makes it difficult to understand fully the ESD field produced by the charged metal bodies. In this paper, the generated electromagnetic field is calculated by the FDTD method (voltage source method), with the spark voltage derived from the spark-resistor law as an excitation source. The result is compared to the results of calculations by the image dipole method and the current source method. It is shown that the waveform of the electrostatic field cannot be calculated by the current source method, but the voltage source method can calculate the field as in the case of the image dipole method. It is also seen that the magnetic field waveforms obtained by any calculation almost completely agree. The magnetic field waveform generated in the discharge experiment between metal spheres is observed by using a shielded magnetic field probe and a wideband oscilloscope (bandwidth 1.5 GHz), and is shown to agree almost completely with the results of calculations by the voltage source method and the image dipole method. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 86(7): 54–63, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1169 [ABSTRACT FROM AUTHOR]

The use of magnetic materials has drawn attention as a method of simultaneously realizing suppression of electromagnetic (EM) noise radiated from information devices and improvement of the immunity of such equipment against the EM noise from these devices. Suppression effect of the electromagnetic noise radiated from printed circuit boards (PCB) traces and cables by ferrite cores and sheets has been studied. However, little is known about the relationship between the mounting location of the ferrite materials and the noise suppression effect. In this paper, a transmission line on the ground plane for the transverse electromagnetic mode is treated. The radiated field at a sufficient distance relative to the transmission line length is analyzed. It is shown that the field level in this case is proportional to the spatial average value of the current distribution on the transmission line in the length direction and hence that reduction of the field level is possible by suppressing the average value of the current. Next, a computational formula is derived for the field level from the ferrite core-attached transmission line. Using this formula, the suppression effect of the field level by core attachment is numerically studied. It is found that a suppression effect is recognizable if the ferrite core is installed at the near end of the transmission line. On the other hand, the field level actually increases if the ferrite core is installed at the far end. These numerical results are confirmed to agree well with experimental results obtained in a six-surface anechoic chamber. Hence, the formula derived in this paper is valid. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 86(5): 12–20, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10050 [ABSTRACT FROM AUTHOR]

Compares the electromagnetic absorption characteristics in realistic human head models of adult and children for 900-MHz mobile telephones. Dosimetry in children's heads for mobile telephones; Spatial peak specific absorption rate in children's heads.

Transient electromagnetic noise generated by ESD (ElectroStatic Discharge) is considered to cause serious electromagnetic interference to high-tech devices. One of the main causes of this ESD is known to be charging of the human body. Hence, the static capacitance of the human body, which is deeply related to the human body potential, has been measured. However, the body capacitance is strongly dependent on the relationship between the ground plane and the body posture. It is therefore not clear what factors govern the body capacitance. In this paper, the static capacitance of a body standing on a ground plane is calculated by means of the surface charge method. The human body consists of polyhedra in the calculation. In this paper, three types of polyhedra, with 765, 917, and 1529 surfaces, are used. It is found that the capacitance increases as the backs of the soles of the shoes approach the ground plane, that the body capacitance at the same height (10 mm) as the soles of the shoes is 120 to 130 pF, and that it is about 60 pF if the location of the soles is sufficiently high. The computational findings are confirmed by measurement of the body capacitance. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(12): 38–44, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10025 [ABSTRACT FROM AUTHOR]

With explosive growth of the use of portable telephones, the public has become concerned with how the radio waves generated by the phones may affect the human body. Developed countries started setting local absorption limits and standards for body protection from the portable phones. However, different countries use different methods of evaluation for the local absorption rate of electric energy which was introduced as the evaluation criterion (SAR: Specific Absorption Rate). Generally speaking, quantitative analysis of SAR in the human body exposed to electromagnetic radiation is referred to as dosimetry. This article offers a discussion of the current situation and problems relating to dosimetry based mainly on the results of domestic and foreign research of in-head dosimetry for portable phones. The authors also offer their views on methods of evaluation of the safety of portable telephones and identify problems to be considered in the future. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(7): 12–22, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/ecja.1107 [ABSTRACT FROM AUTHOR]

The transient electromagnetic fields due to electrostatic discharge (ESD) between charged metals have wide-band frequency spectra up to the microwave region, which create a serious malfunction for high-tech information devices. For the above ESD fields, we previously analyzed them, using the finite-difference time-domain (FDTD) method, and showed that the metals enhance the field level according to the metal dimension. From the standpoint of reducing such ESD fields, the electromagnetic fields caused by the spark between the metals with ferrite core attachments were investigated. The FDTD method was also used to compute the ESD fields. An FDTD algorithm for the magnetic field inside the ferrite core was newly derived. The results show that the cores attached near the spark gap considerably reduce the magnetic field level, which is also confirmed experimentally. © 2001 Scripta Technica, Electr Eng Jpn, 138(1): 34–41, 2002 [ABSTRACT FROM AUTHOR]

Presents a computer model for predicting electromagnetic interference (EMI) levels of implanted pacemakers due to mobile telephones. Multistep approach used in predicting EMI levels; Design guidelines for pacemaker structure and immunity capacity.

It is not known what kind of influence metallic bodies exert on the transient electromagnetic field generated by a spark discharge between charged metals. In this article, the electromagnetic fields generated by spark discharges between metallic spheres are numerically analyzed by the finite-difference time-domain (FDTD) method. It is found that the presence of the metallic bodies can increase the field level depending on their size. Next, the condition for maintaining the metallic spherical surfaces at a constant potential is created by an image charge pair. The generated magnetic field is derived by superposing the electromagnetic fields by the dipole models with the same charge pair. The numerical results almost entirely agree with those obtained by the FDTD method. The validity of the FDTD findings is confirmed. © 2000 Scripta Technica, Electron Comm Jpn Pt 2, 83(2): 44–51, 2000 [ABSTRACT FROM AUTHOR]

The bioeffects of the electromagnetic fields of mobile telephones on the human body are a matter of concern, and the localized specific absorption rate (SAR) of the brain due to near-field exposure has attracted attention. Limiting the effects of radiofrequency electromagnetic fields on the human body to thermal ones, temperature rises are estimated to be caused by the SAR in the brain, including the body temperature–regulating center. In this paper, the temperature rises inside the brain due to exposure to 1.5-GHz microwaves are analyzed by the FDTD method, using a realistic model of the human head developed by the authors. It is found that the peak temperature rise occurs in the eye and muscle tissues. Such temperature rise is at most 0.35 °C at the safe exposure level of 5 mW/cm2 specified in controlled environments in Japan. The rise in the hypothalamus, which regulates the temperature distribution over the human body, is only 0.0026 °C, which is two orders of magnitude smaller than its regulating induction-threshold of 0.3 °C. © 1998 Scripta Technica, Electron Comm Jpn Pt 1, 82(3): 11–19, 1999 [ABSTRACT FROM AUTHOR]

Computes temperature rises in the human head for portable telephones and its health implications. Computation method; Application of the finite-difference time-domain method; Electrical properties of tissues; Boundary conditions; Trends in temperature increases.

Digital equipment with various high-speed, low-power ICs is vulnerable to electrostatic discharge (ESD) and a method to avoid this problem should be developed. Since ESD often is generated by a human while walking, the ESD generating mechanism must be well understood to prevent ESD. This paper proposes a method to estimate the generated charge by evaluating the potential of the human body while walking. Assuming that the basic human motions consist of the up and down movement of the feet, the potential of the human body and generated charges for every step were measured. As a result, it was found that the potential and charges in the human body caused by steps reach a steady state within 800 ms, the potential is lower than 700 V, and the charges are less than 100nC. The capacitance of the human body changes according to motion and is around 200 pF. When one foot is raised, the body capacitance is 70 percent of that when both feet are grounded. The body potential is dependent on the kind of foot motion, that is, in continuous walk, the body potential is negative and its absolute value increases continuously. In stepping, the potential vibrates with a constant amplitude. These characteristics can be explained from the charging characteristics for the basic body motions. [ABSTRACT FROM AUTHOR]

The transient electromagnetic wave generated by electrostatic discharge (ESD) has a spectrum of wide frequency range and causes unpredictable errors in the operation of highly technical electronic apparatus, posing serious problems in our high information society. The charging of a walking body is assumed to be one main cause of ESD, and the use of a floor material of low electric resistance is recommended, but its effects are not as yet clearly understood. We have proposed a model of the mechanism of decay of charged potential of the human body on the flooring materials, and the validity of the model has been proved experimentally. But in the theory, the electrostatic capacity is introduced a priori between the flooring materials and iron reinforcing bar that is the reference of an electric potential. The electrostatic capacity is the quantity defined by the potential and electric charge of the conductor and not defined between the insulators, such as flooring material and conductors. On the other hand, in his book Murasaki insists on the necessity of the electrostatic capacity between the charged insulator and conductor as an “imaginary quantity” for understanding electrostatic damage, but this is not supported by electromagnetic theory. In this paper, the coincidence of the former result from electric circuit analysis and our new result from electromagnetic field theoretic analysis supports the correctness of the “imaginary quantity” of the electrostatic capacity to the flooring materials. © 1998 Scripta Technica, Electron Comm Jpn Pt 1, 81(9): 28–35, 1998 [ABSTRACT FROM AUTHOR]

Ferrite core is installed in a cable and a wiring with a view to improving immunity to electromagnetic noise and reducing the electromagnetic noise generated by digital information devices. The impedance of the ferrite core at the installed location increases with frequency so that the noise current is suppressed. However, this mechanism has not been resolved theoretically in terms of the relationship between the core dimensions and the material constants. In this paper, the high frequency impedance generated by the ferrite core attachment is analyzed so that the equivalent circuit of the load effect is presented. Also, a method is presented for determination of the core shape that effectively enhances the load effect per unit length of the core with appropriate dimensions. Further, in order to confirm the validity of the equivalent circuit, measurement and calculation of the vector impedance are carried out. It is shown that both agree well and that the frequency dispersion parameter of the core permeability obtained from the circuit parameter satisfies Snoek's limit law. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 1, 80(9): 19–24, 1997 [ABSTRACT FROM AUTHOR]

It has been widely accepted that physical stimulation—such as illumination, music, and environmental variables—that has a 1/f fluctuation power spectrum produces relaxation. There should, however, exist a number of stimulation waveforms that have 1/f power spectral characteristics, and thus the parameters of the waveform in the time domain that cause comfortable biostimulation remain unknown. As a first step in elucidating what kinds of biostimulation waveforms produce relaxation, this paper theoretically derives the CRD (crossing rate distribution: the number of times per second that the amplitude crosses various levels in the positive direction) and APD (amplitude probability distribution) for a Gaussian fluctuation waveform with a 1/f-like power spectrum. Flame fluctuation of candles, which is said to produce a sedative effect, is statistically measured. The findings obtained here show that the flame has a peak crossing rate between 0.08 and 0.4 Hz, fluctuating with a rhythm close to that of blood pressure (0.1 Hz) or breathing (0.25 to 0.33 Hz). © 1998 Scripta Technica. Electr Eng Jpn, 121(4): 48–55, 1997 [ABSTRACT FROM AUTHOR]

The skin tissue of the human head can play an electromagnetic shielding role in protecting the central organs from microwave exposure. For the electrical properties, however, the published data are for a wide range of tissues from fat (low water content) to muscle (high water content), and thus various electrical properties of the skin tissue are used for SAR calculations in a heterogeneous head model. This paper examines numerically how variations in the electrical properties of the skin tissue affect the SAR in the human head. Skin tissue properties are newly estimated from the Debye equation with two relaxation time constants, which are used to calculate the SAR in the developed heterogeneous head model for 1.5-GHz microwave exposure. The SAR details are compared with the following cases: results computed for skin having the same electrical properties as those of fat, our previously obtained results, and Furse's results on tissue properties. The effects of tissue mass densities on the SAR calculation are also examined. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(4): 66–73, 1997 [ABSTRACT FROM AUTHOR]

Located near Japan's most densely populated and industrially active region, the Nankai Trough subduction zone has long been highlighted as a high-risk area for damaging earthquakes and tsunamis. In contrast, less attention has been paid the adjacent Ryukyu Trench because historical and geological records are scarce. In order to develop better quantitative estimates of the timing and size of the earthquakes and tsunamis generated along these subduction zones, comprehensive studies using geological, seismological and historical methods have been conducted. Since the 1990s, studies of tsunami deposits in this region have contributed to our current understanding of the history of tsunamis over the last 6000 years. Following the 2011 Tōhoku earthquake and tsunami, paleotsunami research has especially focused on guiding and enhancing tsunami disaster management and mitigation measures. The last nine years have seen a rapid increase in paleotsunami data from the Nankai Trough and Ryukyu Trench coasts. These recent studies reveal that there are significant differences in the size and recurrence pattern of earthquakes and tsunamis along these subduction zones. For instance, large earthquakes have repeatedly occurred along the Nankai Trough every 100–200 years. On the other hand, large earthquakes and tsunamis may not have occurred over the last few thousand years at the junction between these subduction zones. There is also no evidence for the occurrence of large earthquakes along the northern and central Ryukyu Trench over this time period. Large earthquakes and tsunamis may have occurred every few hundred years at the southern end of the Ryukyu Trench. Nevertheless, data on the occurrence of these earthquakes are still insufficient, both in quantity and quality, to estimate the maximum size or recurrence pattern. • Comparative review of tsunami deposits in the Nankai and Ryukyu subduction zones. • Recurrence mode of great earthquakes and tsunamis based on geological evidence. • Updating the model describing the recurrence mode of great earthquakes. • Discussion about the largest tsunami ever in the region from geological evidence. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue, including one on the Holocene marine terraces around Cape Omaezaki, Japan, one on the thickness and grain size of onshore deposits formed by the 2004 Indian Ocean tsunami at southwestern Thailand and one on sedimentary structures of tsunami deposits.

Study of prehistoric to medieval-age tsunami deposits along a riverbank site near the eastern Nankai Trough, central Japan, show that, not only did Tokai earthquakes occur with a higher frequency than previously thought, but that contemporaneous ruptures of the Tokai and Nankai fault segments were also more common. The site revealed a ∼1-km long coast-normal cross section of the strand plain and exposed four sandy tsunami deposits, each of which indicates inundation over 2 km inland of the coast. Radiocarbon dating of previously studied and newly discovered deposits in the region indicates a shorter recurrence time for Tokai earthquakes and clarifies their linkage with Nankai earthquakes. We attribute the younger two tsunami deposits to the 1498 and 1096 CE Tokai earthquakes. The older two deposits confirm the occurrence of the Tokai earthquakes in 887 CE and in the latest 7th century. These events are not reliably recorded in historical documents in the Tokai region but were noted in the Nankai area. The 887 CE earthquake likely represents a full-length rupture of the Tokai and Nankai segments, as was the case for the 1707 CE earthquake. Integrated with the previous studies, these new results show that nine Tokai earthquakes occurred over the last 1300 years, the oldest in the latest 7th century, and in 887, 1096, 1361, 1498, 1614, 1707, 1854 and 1944 CE. Recalculated recurrence intervals range from 90 to 265 years. Except for the 1498 Meio Tokai earthquake, the Tokai earthquakes occurred simultaneously with Nankai earthquakes. • A new recurrence model of Nankai Trough earthquakes derived from geological data. • Nine Tokai earthquakes occurred over the last 1300 years. • They occurred with a higher frequency than previously thought. • With one exception, they occurred simultaneously with the Nankai earthquakes. [ABSTRACT FROM AUTHOR]

Background: Sepsis is one of the most frequent causes of death in the intensive care unit. Host vascular hypo-responsiveness to vasopressors during septic shock is one of the challenging problems. This study tested the hypothesis that adjunct therapy with peroxynitrite decomposition catalyst (WW-85) would reduce arginine vasopressin (AVP) requirements during sepsis resuscitation, using ovine sepsis model. Methods: Thirteen adult female Merino sheep, previously instrumented with multiple vascular catheters, were subjected to "two-hit" (cotton smoke inhalation and intrapulmonary instillation of live methicillin-resistant Staphylococcus aureus; 3.5 × 1011 colony-forming units) injury. Post injury, animals were awakened and randomly allocated to the following groups: (1) AVP: injured, fluid resuscitated, and titrated with AVP, n = 6 or (2) WW-85 + AVP: injured, fluid resuscitated, treated with WW-85, and titrated with AVP, n = 7. One-hour post injury, a bolus intravenous injection of WW-85 (0.1 mg/kg) was followed by a 23-h continuous infusion (0.02 mg/kg/h). Titration of AVP started at a dose of 0.01 unit/min, when mean arterial pressure (MAP) decreased by 10 mmHg from baseline, despite aggressive fluid resuscitation, and the rate was further adjusted to maintain MAP. After the injury, all animals were placed on a mechanical ventilator and monitored in the conscious state for 24 h. Results: The injury induced severe hypotension refractory to aggressive fluid resuscitation. High doses of AVP were required to partially attenuate the sepsis-induced hypotension. However, the cumulative AVP requirement was significantly reduced by adjunct treatment with WW-85 at 17–24 h after the injury (p < 0.05). Total AVP dose and the highest AVP rate were significantly lower in the WW-85 + AVP group compared to the AVP group (p = 0.02 and 0.04, respectively). Treatment with WW-85 had no adverse effects. In addition, the in vitro effects of AVP on isolated artery diameter changes were abolished with peroxynitrite co-incubation. Conclusions: The modulation of reactive nitrogen species, such as peroxynitrite, may be considered as a novel adjunct treatment option for septic shock associated with vascular hypo-responsiveness to vasopressors. [ABSTRACT FROM AUTHOR]

SUMMARY Electrostatic discharge (ESD) generators must be calibrated for contact discharges with the current waveform specified in International Electro-technical Commission (IEC)61000-4-2; however, there are no requirements in current waveforms due to their bad reproducibility for air discharges in the IEC standard. Nevertheless, the air discharge immunity testing is under obligation in the present standard. This implies that different ESD generators are likely to provide significantly different test results for air discharge testing. In this study, two types of different ESD generators were used to measure discharge currents both for contact and air discharges with respect to charge voltages from 2 kV to 8 kV under the same conditions of experimental environment. As a result, we confirmed that the measured waveforms were almost identical for contact discharges regardless of charge voltages, while we found that they are quite different for air discharges with the same approaching speed when the charge voltages are increased. The latter result is because the generator has different impedance characteristics deriving from its structure, and because the spark lengths from the generators with the same charge voltage are different. A formula for calculating the discharge current from an ESD generator through an ideal switch in lieu of a spark, which was previously derived by us, was also employed to obtain the current waveform peculiar to the generator, in order to reveal that the formula provides the different upper limit of air discharge current peaks according to the generator. [ABSTRACT FROM AUTHOR]

SUMMARY There are few published papers on the whole-body average specific absorption rates (WBA-SARs) in humans for simultaneous exposure to multiple radio frequencies (RFs). In order to evaluate human safety of radiowaves in real environments, in this paper we calculate the WBA-SARs in models of a pregnant woman and 3-year-old child for multiple RF exposure, using measured results on electric field intensities from multiple base station antennas installed for cellular phones with four different radiowave frequencies in an underground shopping mall and with five radiowave frequencies in the neighborhood of an elementary school. The Japan Ministry of Internal Affairs and Communications officially reported these data in 2008. Statistical analyses show that the squared sum ratio of the measured electric field to the corresponding Japanese guideline for the general public is smaller than one-hundredth and one-thousand at most in the underground shopping mall and elementary school areas, respectively. As a result, we found that the WBA-SARs in the pregnant woman and 3-year-old child models calculated at each of the frequencies for base station antennas in both areas are significantly lower than the The International Commission on Non-Ionizing Radiation Protection (ICNIRP) basic restriction (0.08 W/kg) for the general public, and that the sum of the WBA-SARs never exceeds one-hundredth of 0.08 W/kg for simultaneous exposure to multiple RF. [ABSTRACT FROM AUTHOR]

The Holocene succession of the Kiso River delta − a sand-rich, river-dominated delta in central Japan − was analyzed at high temporal and spatial resolution. The results demonstrate how the spatiotemporal distribution of sedimentary facies, gross sediment accumulation rates, and accumulation rates of mud versus sand relate to the geomorphic development of the delta and the post-glacial, sea-level history. The centers of peak mud and sand accumulation have migrated seaward in parallel during a regressive stage from 6.5 ka to the present at the rate of 3–9 m/y. The mud and sand accumulation centers mark the bottom and top, respectively, of the delta-front slope. The sediments of the prograding delta show strong sorting and clear upward coarsening because of the steep slope of the delta front. Such internal topographic control redistributes and separates the coarse and fine fractions of the fluvial input during regression. The topographic-controlled sedimentary segregation constructs delta-front topography, in reverse. Therefore, the proportion of sand to mud in the fluvial input controls the stability of the delta-front morphology. Our modeling of the Kiso River delta may have implications for prediction of coastal flooding adjacent to deltas in other parts of the world. [ABSTRACT FROM AUTHOR]

SUMMARY The World Health Organization (WHO) recommended the necessity of electromagnetic (FM) dosimetry evaluation of pregnant women with fetus and of children as an urgent research subject in 2006, with emphasis on studies of whole-body average specific absorption rates (WBA-SARs) in various numerical models of pregnant woman and children for the purpose of determining the safety limits of WBA-SARs. The current safety limits were determined on the basis of behavior abnormalities in healthy adult animals in radio-frequency FM exposure and FM absorption characteristics at resonant frequencies, but not in experiments using pregnant and young animals. In this investigation, we calculated the voxel SARs and WBA-SARs in anatomically detailed models of pregnant woman and 3-year-old children at their resonant frequencies. The histograms and cumulative relative distributions of the voxel SARs were also derived to determine statistical outliers in the voxel SARs for pregnant woman and 3-year-old child models. We found that the mean voxel SARs agree with the WBA-SARs, and that median voxel SARs in the pregnant woman and 3-year-old child models are 47% and 55% of their means, respectively, and the peak voxel SARs are 70 times the mean in both cases. This suggests the possibility that finite-difference time-domain (FDTD)-calculated WBA-SARs may be overestimated due to the existence of statistical outliers. It was also found that although the total number ratio of voxel SARs for the outliers is 0.36% for the pregnant woman model and 0.34% for the 3-year-old child model, WBA-SARs excluding these outliers are less than those in the pregnant woman and 3-year-old child models by 6.8% and 5.7%, respectively. [ABSTRACT FROM AUTHOR]