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Ceftriaxone (CTRX) forms salts with calcium (Ca) in the gall bladder and bile duct, and induces the formation of gallstones. In this study, factors of CTRX-induced gallstone formation were extracted from the results of a retrospective survey using the Japanese Adverse Drug Event Report (JADER), and the causal relationship between the factors and gallstone formation was investigated. From JADER, 136 patients who developed ‘gallstone-related disorder’ with CTRX as a suspected drug were extracted. The incidence of gallstone-induced adverse effects was high in patients treated with CTRX at a dose exceeding the normal daily dose and in children younger than 10 years old, suggesting that CTRX at a high level is a factor for gallstone formation. Thus, after mixing CTRX and Ca2+ at different concentrations under different pH condition, the number of particles in the solutions was measured using a Coulter counter. As a result, the number of minute particles significantly increased at all pH values when Ca2+ and CTRX were mixed at a concentration of 10 mEq/L or higher and 1.5 g/L or higher, respectively. At pH 6.5 or 7.0, visible crystals were detected when 25 mEq/L of Ca2+ and 2.0 g/L of CTRX were mixed. Based on these findings, attention should be sufficiently paid to the development of ‘gallstone-related disorder’ in pediatric patients and in patients treated with CTRX at a dose exceeding the normal dose. Furthermore, gallstone formation and growth may be promoted when CTRX and Ca2+ coexist at high concentrations under low pH conditions.

The risk of extreme events due to weather and climate change, such as winds of unprecedented magnitude, is predicted to increase throughout this century. Artificial ecosystems, such as coniferous plantation forests, can suffer irreversible deterioration due to even a slight change in environmental conditions. However, few studies have examined the effects of converting natural forests to plantations on their vulnerability to catastrophic winds. By modelling the 2004 windthrow event of Typhoon Songda in northern Japan using the random forest machine learning method, we answered two questions: do Abies plantation forests and natural mixed forests differ in their vulnerability to strong winds and how do winds, topography and forest structure affect their vulnerability. Our results show that Abies plantation forests are more vulnerable to catastrophic wind than natural mixed forests under most conditions. However, the windthrow process was common to both types of forests, and the behaviour of wind inside the forests may determine the windthrow probability. Future management options for adapting to climate change were proposed based on these findings, including modifications of plantation forest structure to reduce windthrow risk and reconversion of plantations to natural forests.

Ensembles of climate change projections created by general circulation models (GCMs) with high resolution are increasingly needed to develop adaptation strategies for regional climate change. The Meteorological Research Institute atmospheric GCM version 3.2 (MRI-AGCM3.2), which is listed in the Coupled Model Intercomparison Project phase 5 (CMIP5), has been typically run with resolutions of 60 km and 20 km. Ensembles of MRI-AGCM3.2 consist of members with multiple cumulus convection schemes and different patterns of future sea surface temperature, and are utilized together with their downscaled data; however, the limited size of the high-resolution ensemble may lead to undesirable biases and uncertainty in future climate projections that will limit its appropriateness and effectiveness for studies on climate change and impact assessments. In this study, to develop a comprehensive understanding of the regional precipitation simulated with MRI-AGCM3.2, we investigate how well MRI-AGCM3.2 simulates the present-day regional precipitation around the globe and compare the uncertainty in future precipitation changes and the change projection itself between MRI-AGCM3.2 and the CMIP5 multiple atmosphere–ocean coupled GCM (AOGCM) ensemble. MRI-AGCM3.2 reduces the bias of the regional mean precipitation obtained with the high-performing CMIP5 models, with a reduction of approximately 20% in the bias over the Tibetan Plateau through East Asia and Australia. When 26 global land regions are considered, MRI-AGCM3.2 simulates the spatial pattern and the regional mean realistically in more regions than the individual CMIP5 models. As for the future projections, in 20 of the 26 regions, the sign of annual precipitation change is identical between the 50th percentiles of the MRI-AGCM3.2 ensemble and the CMIP5 multi-model ensemble. In the other six regions around the tropical South Pacific, the differences in modeling with and without atmosphere–ocean coupling may affect the projections. The uncertainty in future changes in annual precipitation from MRI-AGCM3.2 partially overlaps the maximum–minimum uncertainty range from the full ensemble of the CMIP5 models in all regions. Moreover, on average over individual regions, the projections from MRI-AGCM3.2 spread over roughly 0.8 of the uncertainty range from the high-performing CMIP5 models compared to 0.4 of the range of the full ensemble.

A fully integrated 4 $\times $ 4 802.11abgn/ac/ax transceiver system-on-chip (SoC) with integrated interference analyzer and frequency-dependent in-phase and quadrature (IQ) (FD-IQ) calibration is presented. The FD-IQ technique helps meeting the extremely strict IQ imbalance requirement for 1-K quadratic-amplitude modulation (QAM). The pure current-mode TX baseband (BB) improves SNR to better than 50 dB, and a multi-mode local oscillator (LO) distribution circuit provides non-contiguous operation with the error vector magnitude (EVM) of less than −37 dB. The integrated interference analyzer achieves the highly reliable connection in the presence of the undesired signal and hence improves the frequency usage efficiency by identifying the wireless LAN (WLAN) and other signals in the 2G/5G band.

High-bandwidth (BW) and large-capacity storage systems with NAND Flash memory (hereinafter referred to as “NAND”) have been increasingly required for big data applications, such as the field of advanced biomedical science [1]. However, a conventional NAND interface (I/F), e.g., Toggle DDR, with multi-drop bus topology has a tradeoff between BW and capacity due to the large load capacitance of NAND packages (PKGs). Although increasing the number of parallelized lanes of Toggle DDR improves both BW and capacity, it costs a large number of pins/wires on a controller/PCB. In order to overcome these problems, a daisy-chained serial I/F has been proposed [2]. In the I/F, bridge chips mask large load capacitance of NAND PKGs seen from a controller’s transmitter (TX) so that a 12.8Gb/s downlink is realized. However, the multi-band multiplexing technique employed in [2] has a drawback in the difficulty in implementing an uplink because severe timing control is required for cumulatively multiplexing multiple bands (i.e., channels) in each bridge chip. In order to realize both a downlink and an uplink with lower power consumption, this paper presents a newly developed serial I/F with three key techniques: (1) PAM-4-based 4-channel (4-ch) multiplexing, (2) cascaded CDR circuits in (3) ring topology. The fabricated transceiver (TRX) for the proposed I/F achieves 3.69pJ/b with a BER lower than 10-15 at 25.Gb/s with PRBS31 through 1.84dB of channel loss at 6.4GHz. The proposed I/F can achieve a state-of-the-art FoM (defined as “# of packages × Data Rate / power consumption”) of 1.80PKG.Gb/s/mW.

This study numerically investigates the influences of global warming on Typhoon Vera (1959) by conducting pseudo-global warming experiments. It was found that the intensity of Typhoon Vera will be stronger in warmed climate conditions than in the actual September 1959 condition not only at the time of the typhoon’s maturity but also at the time of the landfall. Sensitivity experiments indicate that this projected increase in the typhoon intensity is robust, by taking into consideration the effects of the increase in sea surface temperature and temperature lapse rate under global warming. The examination of rainfall characteristics over the Kiso River and the Yodo River basin demonstrated that the maximum accumulated rainfall and the maximum hourly rainfall at a certain location within the region are more intensified in the PGW conditions than in the 1959 condition at their worst levels. Robustness and uncertainty of the projected changes in the typhoon impacts are discussed.

Typhoon Mireille (1991) caused devastation over Japan. Assessing the impacts of such an extreme typhoon under global warming is an important task to prevent and mitigate future natural disasters. This study investigated the influences of global warming on the strong winds of Typhoon Mireille by conducting pseudo-global warming (PGW) experiments with a regional model. Since significant damages to forest areas occurred in Kyushu and Tohoku, we compared the typhoon impacts in these two regions. It was demonstrated that on average the mean wind speeds induced by Typhoon Mireille become stronger in Kyushu and weaker in Tohoku under the PGW conditions than under the September 1991 conditions. The difference between the two regions in the future is due to the simulated typhoons under PGW being stronger at lower latitudes and weakening more rapidly at higher latitudes. Thus, the impacts of Typhoon Mireille under a warmed climate are considered to be more severe at a lower latitude and weaker at a higher latitude.

Typhoon Songda (2004), while undergoing an extratropical transition and reintensification over the Sea of Japan, spawned serious damages over forest areas in the northern part of Japan. To clarify influences of anticipated global warming on the typhoon hazard in high-latitude regions, we carried out numerical experiments on Typhoon Songda in a current climate and a pseudo global warming climate and examined the impacts of climate change on the typhoon intensify and windstorms for the region. The typhoon intensity at its maturity becomes stronger in a warming climate, and the typhoon while passing over the Sea of Japan weakens more rapidly in the warming climate. Thus the strong wind over the northern part of Japan in the warming climate also becomes weaker. We examined atmospheric environmental factors in the higher-latitude region: sea surface temperature, vertical shear, and meridional gradient of temperature. It was found that the environmental meridional gradient of temperature at the 500 hPa level is smaller in the warming climate than in the current climate, which indicates that the baroclinicity becomes weak under global warming. The weak baroclinicity makes the typhoon environment unfavorable for the extratropical transition, and therefore, possibly reduces the severity of typhoon wind in northern Japan.

A windthrow refers to the uprooting and overthrowing of trees by the wind. Typhoons are a major cause of windthrows in Japan and are predicted to intensify under global warming. This study aimed to estimate the impact of climate change on windthrows and evaluate possible adaptation measures for sustainable forest management. We incorporated Typhoon Songda (2004) simulation experiments under current and pseudo-global warming (2075–2099, RCP 8.5 scenario) conditions with windthrow modelling in four natural and four artificial (Abies sachalinensis, Pinaceae) forests of Hokkaido. Unexpectedly, pseudo-global warming conditions decreased windthrow probabilities compared with current conditions for both forest types, presumably because wind speeds of the simulated typhoon weakened in Japan’s high-latitude regions. Our results indicate that reconversion of artificial forests into natural forests largely decreased windthrow probability, providing a potential adaptation measure for improved forest management. To fully understand the range of climate-change effects on windthrow in Japan, future studies should use different climate scenarios and data from other typhoons, geographical regions, and forest types.

We review the philosophy and achievements of the research activity on assessing the impacts of global warming on meteorological hazards and risks in Japan under Program for Risk Information on Climate Change (SOUSEI). The concept of this research project consists of assessing worst-class meteorological hazards and evaluating probabilistic information on the occurrence of extreme weather phenomena. Worst-scenario analyses for historical extreme typhoons and probabilistic analyses on Baiu, warm-season rainfalls, and strong winds with the use of high-performance climate model outputs are described. Collaboration among the fields in meteorology, hydrology, coastal engineering, and forest science plays a key role in advancing the impact assessment of meteorological hazards and risks. Based on the present research activity, possible future directions are given.

An exponentially Increasing number of wireless-LAN (WLAN) devices In a dense environment causes a decrease in throughput owing to collisions among the devices and the lack of contiguous bandwidth. The next-generation standard of 802.11ax improves spectrum efficiency by additionally supporting 1024 (1K) QAM, OFDMA with 80+80MHz; these impose several challenges to silicon design. 1K-QAM demands extreme IQ balance with an IRR better than −50dB over a wide frequency range up to 80MHz to achieve at least −35dB RX EVM or less. Noise characteristics better than −44dBc LO integrated phase noise as well as 50dB isolation between each TRX chain are mandatory. To best make use of the essential features defined in the 11ax standard, a real-time and arbitrary spectrum-resource control capability at each access point (AP) is beneficial both in terms of further improvement in spectrum efficiency as well as communication reliability in ISM coexisting bands and legacy WLAN. Interference identification of the order of 10μe while incorporating everything into a strictly limited silicon area is key to launching the advanced unique functionality. This paper presents a fully integrated 4×4 802.11abgn/ac/ax-compliant AP transceiver SoC. The chip offers frequency-dependent IQ (FD-IQ) mismatch calibration for both amplitude and phase, low-noise TX BB and multimode LO distribution techniques, and real-time interference detection including 2.4GHz inverter-type microwave (MW) ovens.

The effects of land reclamations in the Osaka Bay area on the climate in the Keihanshin region are investigated using a numerical model. It is observed that reclamations in Osaka Bay lead to a significant increase in the surface air temperature (SAT) over the inland during the daytime and a decrease from midnight to the morning. This indicates that reclamations increase the diurnal temperature range. The decrease in the SAT in the morning, which is in contrast to urban warming, is due to the decreased surface wind speed caused by the reclamations and is accompanied by reduced vertical heat exchange.