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Dew formation in the rice canopy was directly observed to assess its actual nature and was simulated using a multilayer microclimate model to understand the relationship between the dew amount and atmospheric conditions. Observations were made on four nights during August and October in a paddy field in Kumamoto, Japan under warm temperate climate. The vertical profile of the dew amount in the canopy was measured every 2 h at 0.2 m intervals. The maximum dew amount was recorded in the early morning on all observation days. The total dew amount for the whole canopy at 6:00 on August 19, 21, and 24, and on October 1 was 0.10, 0.07, 0.15, and 0.23 mm, respectively. The dew amount determined from the simulation showed a good agreement with the actual observations. The dew amount per unit leaf area was larger in the upper layers than in the lower layers of the canopy on all days. This vertical difference in the dew amount was explained by the difference in effective radiation (net longwave radiation). The vertical gradient of the dew amount was steep on August 19 and October 1, whereas it was gentle on August 21 and 24. This difference in gradient was explained by the difference in paddy water temperature. When the water temperature was higher than the air temperature, the vertical gradient of the effective radiation and dew amount became steeper. The total amount and source of dew also varied with water temperature. The dominant source of dew was dewfall (water flux from the atmosphere) at lower water temperature, whereas it was distillation (water flux from the ground surface) at higher water temperature. From these results, we conclude that water temperature plays an important role in dew formation in the rice canopy.

In this study, field measurements of the bending moments of prestressed concrete (PC) sleepers installed on commercial lines were obtained, and numerical analyses to identify the effects of different parameters on their bending moments were conducted. The bending load capacities of aged PC sleepers collected from commercial lines via bending tests were also determined. According to the field measurement results of the wheel loads and bending moments of the PC sleepers, the measured values were smaller than the design values. In addition, neither the wheel load nor the bending moment depended on train speed. The numerical analysis results indicate that the positive bending moment at the rail seat section is unlikely to exceed the design decompression moment (DDM). However, the negative bending moment at the center section may exceed the DDM if center support is provided with a reduced spring constant under the rail (the “hanging” rail seat section). In addition, the bending moment increased with the rail surface roughness, so the rail should be kept smooth. Moreover, the results of the JIS E 1201 bending tests on the aged PC sleepers showed that the crack generation load and ultimate load decreased gradually with increases in age and passing tonnage. However, all samples satisfied the JIS standard values. Furthermore, the bending moments generated in the PC sleepers during train passage were considerably smaller than the crack generation load and ultimate load during the bending test. Thus, Japanese PC sleepers aged more than 50 years currently satisfy the standard flexural fracture values specified by the JIS, and safety is not immediately compromised.

We visualize the rates of stay-home for residents by region using the difference between day-time and night-time populations to detect residential areas, and then observing the numbers of people leaving residential areas. There are issues with measuring stay-home rates by observing numbers of people visiting downtown areas, such as central urban shopping centers and major train stations. The first is that we cannot eliminate the possibility that people will avoid areas being observed and go to other areas. The second is that for people visiting downtown areas, we cannot know where they reside. These issues can be resolved if we quantify the degree of stay-home using the number of people leaving residential areas. There are significant differences in stay-home levels by region throughout Japan. By this visualization, residents of each region can see whether their level of stay-home is adequate or not, and this can provide incentive toward compliance suited to the residents of the region.

Quick, easy, cheap, effective, rugged, and safe extraction strategies are becoming increasingly adopted in various analytical fields to determine drugs in biological specimens. In the present study, we developed two fully automated quick, easy, cheap, effective, rugged, and safe extraction methods based on acetonitrile salting-out assisted liquid-liquid extraction (method 1) and acetonitrile salting-out assisted liquid-liquid extraction followed by dispersive solid-phase extraction (method 2) using a commercially available automated liquid-liquid extraction system. We applied these methods to the extraction of 14 psychotropic drugs (11 benzodiazepines and carbamazepine, quetiapine, and zolpidem) from whole blood samples. Both methods prior to liquid chromatography-tandem mass spectrometry analysis exhibited high linearity of calibration curves (correlation coefficients, 0.9997), ppt level detection sensitivities, and satisfactory precisions (8.6% relative standard deviation), accuracies (within ± 16% relative error), and matrix effects (81-111%). Method 1 provided higher recovery rates (80-91%) than method 2 (72-86%), whereas method 2 provided higher detection sensitivities (limits of detection, 0.003-0.094 ng/mL) than method 1 (0.025-0.47 ng/mL) owing to the effectiveness of its dispersive solid-phase extraction cleanup step. These fully automated extraction methods realize reliable, labor-saving, user-friendly, and hygienic extraction of target analytes from whole blood samples.

In connection with recent experiments on excitation in which Mott insulators change to conductors, we study the properties of excited states beyond the Mott gap as quasi-stationary states for a two-dimensional Hubbard (t-t'-U) model at half filling. A variational Monte Carlo method is used with trial wave functions for paramagnetic or normal (PM), superconducting with dx2-y2-wave (d-SC), isotropic s-wave, and extended s-wave symmetries, and antiferromagnetic (AF) states. The excited states are generated by imposing a minimum number of doubly occupied sites (doublons) D_L on the lowest-energy states. For U>W (W: band width), d_L=D_L/Ns (Ns: number of sites) corresponds to the excitation intensity. It is found that the AF state is the most stable among the states we treated for d_L0.14, but the d-SC state is always hidden by the AF state. The s-wave-type superconducting states are not stabilized for any parameter set., 11 pages, 19 figures. To appear in J. Phys. Soc. Jpn

A double-distribution-function lattice Boltzmann model for large-eddy simulations of a passive scalar field in a neutrally stratified turbulent flow is described. In simulations of the scalar turbulence within and above a homogeneous plant canopy, the model’s performance is found to be comparable with that of a conventional large-eddy simulation model based on the Navier–Stokes equations and a scalar advection–diffusion equation in terms of the mean turbulence statistics, budgets of the second moments, power spectra, and spatial two-point correlation functions. For a top-down scalar, for which the plant canopy serves as a distributed sink, the variance and flux of the scalar near the canopy top are predominantly determined by sweep motions originating far above the canopy. These sweep motions, which have spatial scales much larger than the canopy height, penetrate deep inside the canopy and cause scalar sweep events near the canopy floor. By contrast, scalar ejection events near the canopy floor are induced by coherent eddies generated near the canopy top. The generation of such eddies is triggered by the downward approach of massive sweep motions to existing wide regions of weak ejective motions from inside to above the canopy. The non-local transport of scalars from above the canopy to the canopy floor, and vice versa, is driven by these eddies of different origins. Such non-local transport has significant implications for the scalar variance and flux budgets within and above the canopy, as well as the transport of scalars emitted from the underlying soils to the atmosphere.

Changes in people’s behavior during the COVID-19 pandemic can be regarded as the result of two types of effects: the “intervention effect” (changes resulting from government orders or requests for people to change their behavior) and the “information effect” (voluntary changes in people’s behavior based on information about the pandemic). Using mobile location data to construct a stay-at-home measure for different age groups, we examine how the intervention and information effects differ across age groups. Our main findings are as follows. First, the age profile of the intervention effect of the state of emergency declaration in April and May 2020 shows that the degree to which people refrained from going out was smaller for older age groups, who are at a higher risk of serious illness and death, than for younger age groups. Second, the age profile of the information effect shows that, unlike the intervention effect, the degree to which people stayed at home tended to increase with age for weekends and holidays. Thus, while Acemoglu et al. (2020) proposed targeted lockdowns requiring stricter lockdown policies for the oldest group in order to protect those at a high risk of serious illness and death, our findings suggest that Japan’s government intervention had a very different effect in that it primarily reduced outings by the young, and what led to the quarantining of older groups at higher risk instead was people’s voluntary response to information about the pandemic. Third, the information effect has been on a downward trend since the summer of 2020. While this trend applies to all age groups, it is relatively more pronounced among the young, so that the age profile of the information effect remains upward sloping, suggesting that people’s response to information about the pandemic is commensurate with their risk of serious illness and death.

The present paper derives a money demand function that explicitly takes the costs of storing money into account. This function is then used to examine the consequences of the large‐scale money injection conducted by the Bank of Japan since April 2013. The main findings are as follows. First, the opportunity cost of holding money calculated using 1‐year government bond yields has been negative since the fourth quarter of 2014 and most recently (2020:Q2) was −0.2%. Second, the marginal cost of storing money, which was 0.3% in the most recent quarter, exceeds the marginal utility of money, which was 0.1%. Third, the optimal quantity of money, measured by the ratio of M1 to nominal gross domestic product, is 1.2. In contrast, the actual money‐income ratio in the most recent quarter was 1.8. The welfare loss relative to the maximum welfare obtained under the optimal quantity of money in the most recent quarter was 0.2% of nominal gross domestic product. The findings imply that the Bank of Japan needs to reduce M1 by more than 30%, for example through measures that impose a penalty on holding money.

Known as the heat-mitigation effect, irrigated rice-paddy fields distribute a large fraction of their received energy to the latent heat during the growing season. The present hypothesis is that increased atmospheric CO2 concentration decreases the stomatal conductance of rice plants and increases the air temperature by means of an increased sensible heat flux. To test this hypothesis, a coupled regional atmospheric and crop energy-balance model is developed and applied to a 300 × 300 km2 region in Japan. Downscaling meteorological variables from grid-mean values of mixed land use (3 × 3 km2) generates realistic typical diurnal cycles of air temperature in rice paddies and adjacent residential areas. The model simulation shows that, on a typical sunny day in summer, doubling the CO2 concentration increases the daily maximum grid-mean air temperature, particularly where rice paddies are present, by up to 0.7 °C. This CO2 effect on the grid-mean air temperature is approximately half the effect of the reduction in rice-paddy area that is postulated to occur on a time scale similar to that of the atmospheric CO2 change. However, within the internal atmospheric boundary layer of the rice paddies, the CO2 effect on the air temperature (+ 0.44 °C) still exceeds the effects of the land-use change (+ 0.11 °C). These results show a potentially important interplay of plant physiological responses regarding atmospheric CO2 in the heat-mitigation effect of rice-paddy fields under a changing climate.

In this study, we developed an easily operable quantification method for 21 plant-derived alkaloids in human serum by automatic sample preparation and liquid chromatography-tandem mass spectrometry. We designed to perform parallel sample preparation by a developed apparatus, which increased sample throughput. We conducted an automatic sample preparation through de-proteinization with 0.1% formic acid in methanol and achieved recovery rates of 89-107% (2.0-14% RSD) for all targeted analytes, demonstrating its high repeatability. The method validation results were satisfactory as follows: the linearity (The online version contains supplementary material available at 10.1007/s10337-022-04212-5.

A central-moments-based lattice Boltzmann model for large-eddy simulation of neutrally-stratified turbulent flows is described. Through comparative simulations of the airflow within and above a homogeneous plant canopy, the performance of the model is evaluated with respect to a conventional large-eddy-simulation model based on the incompressible Navier–Stokes equations. Simulated turbulence statistics, such as the mean velocity, velocity variances, velocity skewness, and power spectra, are shown to be almost identical between the two models. The spatial structure of coherent eddies and their maintenance processes are also confirmed to be properly represented by the lattice Boltzmann method through analysis of the turbulence kinetic energy budget and spatial two-point correlation functions. Using the simulated results, the energetics of the streamwise-elongated streaky structures commonly observed over vegetation and urban canopies are examined. While the short-wavelength components of the shear-generated streamwise kinetic energy are redirected rapidly by pressure to the lateral and vertical velocity components, long-wavelength energy tends to remain in the streamwise velocity component, which is dissipated in relatively slower processes. Consequently, the streaky structures persist in the streamwise velocity component.

Using a new micro-level dataset we investigate the relationship between the inflation experience and inflation expectations of individuals in Japan. We focus on the period after 1995, when Japan began its era of deflation. Our key findings are fourfold. Firstly, we find that inflation expectations tend to increase with age. Secondly, we find that measured inflation rates of items purchased also increase with age. However, we find that age and inflation expectations continue to have a positive correlation even after controlling for the individual-level rate of inflation. Further analysis suggests that the positive correlation between age and inflation expectations is driven to a signi cant degree by the correlation between cohort and inflation expectations, which we interpret to represent the effect of historical inflation experience on expectations of future inflation rates.