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Abstract To control the COVID-19 epidemic, the Japanese government and the local governments have repeatedly implemented non-pharmaceutical interventions (NPIs) throughout 2020–2022. Using Bayesian state-space mediation models, we examined the effect of repeated NPIs on infection spread mitigation, mediated by human mobility changes in each prefecture during three epidemic phases: from April 1, 2020 to February 28, 2021; from March 1, 2021 to December 16, 2021; and from December 17, 2021 to December 31, 2022. In the first phase, controlling downtown populations at nighttime was effective in mitigating the infection spread in almost all prefectures. In the second and third phases, the effect was not clear, especially in metropolitan prefectures. Controlling visitors from the central prefectures of metropolitan areas was effective in mitigating infection spread in the surrounding prefectures during all phases. These results suggest that the local spread of infection can be mitigated by focusing on nighttime human mobility control in downtown areas before the epidemic spreads widely and transmission routes become more diverse, and that the geospatial spread of infection can be prevented by controlling the flows of people from large cities to other areas.

Abstract Natural Killer (NK) cells are pivotal in immune responses to viral infections, malignancies, autoimmune diseases, and transplantation. Assessment of NK cell adhesion, migration, and cytotoxicity is fundamental for in vitro studies. We propose a novel live-cell tracking method that addresses these three major aspects of NK cell function using human NK cells and primary porcine aortic endothelial cells (PAECs) in two-dimensional (2D) static assays and an in-house cylindrical 3D microfluidic system. The results showed a significant increase of NK cytotoxicity against pTNF-activated PAECs, with apoptotic cell death observed in the majority of dead cells, while no difference was observed in the conventional Delfia assay. Computed analysis of NK cell trajectories revealed distinct migratory behaviors, including trajectory length, diameter, average speed, and arrest coefficient. In 3D microfluidic experiments, NK cell attachment to pTNF-activated PAECs substantially increased, accompanied by more dead PAECs compared to control conditions. NK cell trajectories showed versatile migration in various directions and interactions with PAECs. This study uniquely demonstrates NK attachment and killing in a 3D system that mimics blood vessel conditions. Our microscope method offers sensitive single-cell level results, addressing diverse aspects of NK functions. It is adaptable for studying other immune and target cells, providing insights into various biological questions.

Abstract This work presents a 2D tellurium (Te)‐based diode that exploits the doping achieved by atomic layer deposited (ALD) Al2O3 to enhance its rectifying performance. The proposed device comprises a Schottky junction that is dielectric‐doped to significantly reduce the reverse bias current. A boosted current responsivity four times higher compared to that of undoped devices is achieved, maximizing the performance for radio frequency (RF) power detectors. The application measurement results demonstrate sensitivities as low as −45 dBm, and at −30 dBm RF input power outstanding tangential responsivities up to 6.5 kV W–1, 4.3 kV W–1, and 650 V W–1 at 0.5, 1, and 2.5 GHz, respectively, while reaching linear dynamic range (DR) of over 30 dB. These are the highest reported values for 2D‐based material devices by almost two orders of magnitude. Furthermore, the DR is ≈10 dB larger compared to state‐of‐the‐art power detectors based on bulk semiconductors.

Abstract Spatiotemporal data on ambient populations have recently become widely available. Although previous studies have indicated a link between the spatial patterns of crime occurrence and ambient population distribution, more detailed information, such as the population most likely to be victims by gender and age group, could better predict the risk of crime occurrence. Therefore, this study aimed to analyze the risk of indecent assault, a typical crime with a high number of young female victims, in southern Kyoto Prefecture. We utilized population distribution by gender and age group at different times of the day. After extracting daily patterns (factors) of the population using non-negative matrix factorization, we statistically modeled the risk of indecent assault using a spatial conditional autoregressive model. The results showed that the model, which considered a spatiotemporal ambient population, demonstrated superior performance during nighttime hours. Furthermore, by interpreting the factors significantly associated with the risk of crime occurrence, the findings provided valuable insights into local crime prevention measures that consider daily temporal changes in the gender and age-group composition of individuals present in a specific area.

Abstract The research of two-dimensional (2D) Tellurium (Te) or tellurene is thriving to address current challenges in emerging thin-film electronic and optoelectronic devices. However, the study of 2D-Te-based devices for high-frequency applications is still lacking in the literature. This work presents a comprehensive study of two types of radio frequency (RF) diodes based on 2D-Te flakes and exploits their distinct properties in two RF applications. First, a metal-insulator-semiconductor (MIS) structure is employed as a nonlinear device in a passive RF mixer, where the achieved conversion loss at 2.5 GHz and 5 GHz is as low as 24 dB and 29 dB, respectively. Then, a metal-semiconductor (MS) diode is tested as a zero-bias millimeter-wave power detector and reaches an outstanding linear-in-dB dynamic range over 40 dB, while having voltage responsivities as high as 257 V ⋅ W−1 at 1 GHz (up to 1 V detected output voltage) and 47 V ⋅ W−1 at 2.5 GHz (up to 0.26 V detected output voltage). These results show superior performance compared to other 2D material-based devices in a much more mature technological phase. Thus, the authors believe that this work demonstrates the potential of 2D-Te as a promising material for devices in emerging high-frequency electronics.

Morphology governs function. Yet, understanding and controlling the emergence of morphology at the molecular level remains challenging. The difficulty in studying the early stage of morphology formation is due to its stochastic nature both spatially and temporally occurring at the nanoscale. This nature has been particularly detrimental for the application of optical spectroscopy. To overcome this problem, we have been developing new in situ/in vivo optical spectroscopy tools, which are label-free and non-invasive. This account highlights several examples of how optical spectroscopy can become an important tool in studying the birth of morphology.

Detection of cytokine biomarkers has the potential to aid in diagnosis and treatment of different diseases. Here, the authors report on the creation of an asymmetric geometry MoS2 diode-based biosensor for the detection of TNF-α as a model biomarker in a proof of concept study.

Abstract With the advent of spatial analysis, the importance of analyzing crime patterns based on location has become more apparent. Previous studies have advanced our understanding of the factors associated with crime concentration in street networks. However, it has recently become possible to assess the factors associated with crime at even finer spatial scales of streetscapes, such as the existence of greenery or walls, owing to the availability of streetscape image data and progress in machine learning-based image analysis. Such place-scale environments can be both crime-producing and crime-preventing, depending on the composition of the streetscape environment. In this study, we attempted to assess the risk of crime occurrence through place-scale indicators using streetscape images and their interaction terms through binomial logistic regression modeling of the place-scale crime risk of theft from vehicles in the central part of Kyoto City, Japan. The results suggest that the effects of specific streetscape components on the risk of crime occurrence are certainly dependent on other components. For example, the association of the crime occurrence risk with the occupancy rate of vegetation in a streetscape image is positive when there are few buildings and walls, and vice versa. The findings of this study show the importance of considering the complex composition of visible streetscape components in assessing the place-scale risk of crime occurrence.

Transition metal dichalcogenides have gained considerable interest for vapour sensing applications due to their large surface-to-volume ratio and high sensitivity. Herein, we demonstrate a new self-powered volatile organic compounds (VOC) sensor based on asymmetric geometry multi-layer molybdenum disulfide (MoS _2 ) diode. The asymmetric contact geometry of the MoS _2 diode induces an internal built-in electric field resulting in self-powering via a photovoltaic response. While illuminated by UV-light, the sensor exhibited a high responsivity of ∼60% with a relatively fast response time of ∼10 sec to 200 ppm of acetone, without an external bias voltage. The MoS _2 VOC diode sensor is a promising candidate for self-powered, fast, portable, and highly sensitive VOC sensor applications.

Abstract Volatile organic compounds (VOCs) sensors have a broad range of applications including healthcare, process control, and air quality analysis. There are a variety of techniques for detecting VOCs such as optical, acoustic, electrochemical, and chemiresistive sensors. However, existing commercial VOC detectors have drawbacks such as high cost, large size, or lack of selectivity. Herein, a new sensing mechanism is demonstrated based on surface interactions between VOC and UV‐excited 2D germanium sulfide (GeS), which provides an effective solution to distinguish VOCs. The GeS sensor shows a unique time‐resolved electrical response to different VOC species, facilitating identification and qualitative measurement of VOCs. Moreover, machine learning is utilized to distinguish VOC species from their dynamic response via visualization with high accuracy. The proposed approach demonstrates the potential of 2D GeS as a promising candidate for selective miniature VOCs sensors in critical applications such as non‐invasive diagnosis of diseases and health monitoring.

Three-dimensional point clouds are becoming popular representations for digital archives of cultural heritage sites. The Borobudur Temple, located in Central Java, Indonesia, was built in the 8th century. Borobudur is considered one of the greatest Buddhist monuments in the world and was listed as a UNESCO World Heritage site. We are developing a virtual reality system as a digital archive of the Borobudur Temple. This research is a collaboration between Ritsumeikan University, Japan, the Indonesian Institute of Sciences (LIPI), and the Borobudur Conservation Office, Indonesia. In our VR system, the following three data sources are integrated to form a 3D point cloud: (1) a 3D point cloud of the overall shape of the temple acquired by photogrammetry using a camera carried by a UAV, (2) a 3D point cloud obtained from precise photogrammetric measurements of selected parts of the temple building, and (3) 3D data of the hidden relief panels recovered from the archived 2D monocular photos using deep learning. Our VR system supports both the first-person view and the bird’s eye view. The first-person view allows immersive observation and appreciation of the cultural heritage. The bird’s eye view is useful for understanding the whole picture. A user can easily switch between the two views by using a user-friendly VR user interface constructed by a 3D game engine.

The recent development of 3D scanning technologies has made it possible to quickly and accurately record various 3D objects in the real world. The 3D scanned data take the form of large-scale point clouds, which describe complex 3D structures of the target objects and the surrounding scenes. The complexity becomes significant in cases that a scanned object has internal 3D structures, and the acquired point cloud is created by merging the scanning results of both the interior and surface shapes. To observe the whole 3D structure of such complex point-based objects, the point-based transparent visualization, which we recently proposed, is useful because we can observe the internal 3D structures as well as the surface shapes based on high-quality see-through 3D images. However, transparent visualization sometimes shows us too much information so that the generated images become confusing. To address this problem, in this paper, we propose to combine “edge highlighting” with transparent visualization. This combination makes the created see-through images quite understandable because we can highlight the 3D edges of visualized shapes as high-curvature areas. In addition, to make the combination more effective, we propose a new edge highlighting method applicable to 3D scanned point clouds. We call the method “opacity-based edge highlighting,” which appropriately utilizes the effect of transparency to make the 3D edge regions look clearer. The proposed method works well for both sharp (high-curvature) and soft (low-curvature) 3D edges. We show several experiments that demonstrate our method’s effectiveness by using real 3D scanned point clouds.

Studies from many countries, including Japan, have reported decreased physical activity during the coronavirus disease 2019 (COVID-19) pandemic. However, the individual attributes as related to changes in physical activity during the pandemic in Japan have been scarcely investigated. The present study explored the relationships among individual attributes including demographic, socioeconomic, and geographic characteristics, work situation changes, perception of anxiety, and changes in walking and sedentary behaviors, during the pandemic in Japan. To obtain data indicating individual circumstances during the first wave of the pandemic in Japan, we conducted a nationwide online survey from May 19 to May 23, 2020 (n = 1,200). To observe changes in walking behavior objectively and retrospectively, we collected data on the number of daily steps as measured by the iPhone’s Health application. Path analysis was employed to examine relationships between individual attributes and changes in walking and sedentary behaviors. Decreased physical activity, especially, decreased walking behavior among younger individuals and those living in highest-density neighborhoods were identified. There was increased sedentary behavior among females. Moreover, individuals with higher socioeconomic status (SES) tended to become inactive due to work-from-home/standby-at-home and individuals with lower SES tended to become inactive due to decreased amount of work. Decreased walking behavior and increased sedentary behavior were associated with a perception of strong anxiety related to the pandemic. Our findings would be helpful in considering measures to counteract health risks during the pandemic by taking into account individual backgrounds.

Following the first wave of the COVID-19 outbreak, the Japanese government announced the declaration of a state of emergency in April 2020, which aimed to decrease contact between people and requested that residents refrain from outings. Even in the absence of penalties, outings decreased under the declaration. We are interested in how outings declined and studied the substitution relationship between Internet use and outings. A web-based survey was conducted to collect data on Internet use and outings in a retrospective manner. The period covered by our data is from mid-February to mid-May 2020. Multilevel analysis and binomial logistic regression analysis were performed to examine the relationship between Internet use and outings. The results clearly show that Internet use replaced outings. In particular, Internet use for socializing, exercise, and leisure/entertainment had a strong substitution relationship with outings. Internet use for socializing and leisure/entertainment was also associated with refraining from visiting restaurants. In contrast, there was a weak substitution relationship between Internet use for daily shopping and outings. Although telework tends to be an accepted focus of Internet use under the COVID-19 outbreak, it should not be overlooked that other uses of the Internet, such as for leisure/entertainment, also supported the decline in outings.

Background: The aim of this study was to increase knowledge regarding the dangers associated with tobacco use, and decrease secondhand smoke exposure and tobacco use behaviors with an antitobacco messaging campaign among rural, medically underserved, blue-collar workers. Methods: A quasiexperimental study was conducted with employees at two worksites. One worksite received the intervention, which consisted of nine different antitobacco messages. Baseline and follow-up surveys were conducted at each worksite to assess change in knowledge and behavior; the data were compared across the two worksites. Results: Two hundred twenty-two and 243 participants completed baseline and follow-up surveys at the intervention and comparison sites, respectively. A statistically significant difference was seen over time between the worksites on knowledge of the dangers of tobacco (p

In 2010, eight companies which are exploiting natural gas and brine water in the Southern Kanto natural gas field, Chiba prefecture, Japan constructed an in-situ formation deformation monitoring well with a depth of approximately 80 m, and in-situ formation deformation was measured on a trial basis. After this field test, by conducting the simulation study, we verified whether the deformation behavior at the monitoring well was perfectly elastic or not. In addition, we compared in-situ rock properties like Young's modulus and Poisson's ratio which were estimated by the simulation study with those determined from a triaxial compression test.

A simulation model, which covers the part of Southern-Kanto natural gas field in Chiba prefecture, was developed to perform studies and make predictions of land subsidence. However, because large differences between simulated and measured subsidence occurred in the northern modeled area of the gas field, the model was modified with an estimated Young's modulus distribution. This distribution was estimated by the yield value distribution and the correlation of yield value with Young's modulus. Consequently, the simulated subsidence in the north area was improved to some extent.

More reliable estimates of the carbon (C) stock within forest ecosystems and C emission induced by deforestation are urgently needed to mitigate the effects of emissions on climate change. A process-based terrestrial biogeochemical model (VISIT) was applied to tropical primary forests of two types (a seasonal dry forest in Thailand and a rainforest in Malaysia) and one agro-forest (an oil palm plantation in Malaysia) to estimate the C budget of tropical ecosystems in Southeast Asia, including the impacts of land-use conversion. The observed aboveground biomass in the seasonal dry tropical forest in Thailand (226.3 t C ha−1) and the rainforest in Malaysia (201.5 t C ha−1) indicate that tropical forests of Southeast Asia are among the most C-abundant ecosystems in the world. The model simulation results in rainforests were consistent with field data, except for the NEP, however, the VISIT model tended to underestimate C budget and stock in the seasonal dry tropical forest. The gross primary production (GPP) based on field observations ranged from 32.0 to 39.6 t C ha−1 yr−1 in the two primary forests, whereas the model slightly underestimated GPP (26.5–34.5 t C ha−1 yr−1). The VISIT model appropriately captured the impacts of disturbances such as deforestation and land-use conversions on the C budget. Results of sensitivity analysis showed that the proportion of remaining residual debris was a key parameter determining the soil C budget after the deforestation event. According to the model simulation, the total C stock (total biomass and soil C) of the oil palm plantation was about 35% of the rainforest's C stock at 30 yr following initiation of the plantation. However, there were few field data of C budget and stock, especially in oil palm plantation. The C budget of each ecosystem must be evaluated over the long term using both the model simulations and observations to understand the effects of climate and land-use conversion on C budgets in tropical forest ecosystems.

Paddy fields are an important source of atmospheric CH4, the second most important greenhouse gas. There is a strong concern that the increasing atmospheric CO2 concentration ([CO2]) and global warming are further stimulating CH4 emissions, but the magnitude of this stimulation varies substantially by study, and few open-field evaluations have been conducted. Here we report results obtained at a Japanese rice free-air CO2 enrichment (FACE) site under water and soil temperature elevation during two growing seasons. Our objectives were to evaluate the effects of high [CO2] (ambient + 200 μmol mol−1) and elevated soil temperature (+ 2 °C) on CH4 emissions under completely open-field conditions. We found about 80% enhancement in total seasonal emissions by the additive effects of FACE and warming, indicating a strong positive feedback effect of global warming. The enhancement in CH4 emission from the FACE-effect alone (+ 26%) was statistically non-significant (P = 0.19). Nevertheless, observed positive correlations between CH4 emissions and rice biomass agreed well with previous studies, suggesting that higher photosynthesis led to greater rhizodeposition, which then acted as substrates for methanogenesis. Soil warming increased the emission by 44% (P < 0.001), which was equivalent to a Q10 of 5.5. Increased rice biomass by warming could only partly explain the enhanced CH4 emissions, but stoichiometric analysis of the electron budget indicated that even a moderate enhancement in organic matter decomposition due to soil warming can cause a large increase in CH4 production under conditions where Fe(III) reduction, which was little affected by soil warming, dominates electron-accepting processes. At later rice growth stages, advanced root senescence due to elevated temperature probably provided more substrate for methanogenesis. Our stoichiometric evaluation showed that in situ Fe reduction characteristics and root turnover in response to elevated temperature should be understood to correctly predict future CH4 emissions from paddy fields under a changing climate. Challenges remain for determination of in situ root-exudation rate and its response to FACE and warming.

Phase‐locking of two longitudinal oscillating modes of a dual‐mode microchip laser that has 101 GHz longitudinal‐mode spacing has been successfully demonstrated by using electronic negative‐feedback control. Since the two longitudinal modes were oscillating simultaneously in the same laser cavity, the common‐mode fluctuation cancels, resulted in the small required control bandwidth of ∼4 kHz. This narrow‐bandwidth phase‐locking technique is useful for generating high‐spectral‐purity millimetre‐wave signals with a considerably simpler setup.

The influence of roxithromycin (RXM) on the expression of co-stimulatory molecules, CD40, CD80 and CD86, was examined in vivo. When BALB/c mice were immunized intraperitoneally with two doses of dinitrophenylated ovalbumin (DNP-OVA) at 1 week intervals, intraperitoneal administration of RXM at 250 μg/kg once a day for 14 days strongly suppressed IgE contents in sera obtained from mice 22 days after the first immunization. In addition, RXM treatment of mice suppressed endogenous IL–4 contents in aqueous spleen extracts, which were enhanced by DNP-OVA immunization. We next examined the influence of RXM on co-stimulatory molecule expression on splenic lymphocytes. RXM treatment of the immunized mice caused suppression of CD40 expression, but this treatment did not affect CD80 and CD86 expression.

Quick service restaurant (QSR) television advertisements for children's meals were compared with adult advertisements from the same companies to assess whether self-regulatory pledges for food advertisements to children had been implemented.All nationally televised advertisements for the top 25 US QSR restaurants from July 1, 2009 to June 30, 2010 were obtained and viewed to identify those advertising meals for children and these advertisements were compared with adult advertisements from the same companies. Content coding included visual and audio assessment of branding, toy premiums, movie tie-ins, and depictions of food. For image size comparisons, the diagonal length of the advertisement was compared with the diagonal length of salient food and drink images.Almost all of the 92 QSR children's meal advertisements that aired during the study period were attributable to McDonald's (70%) or Burger King (29%); 79% of 25,000 television placements aired on just four channels (Cartoon Network, Nickelodeon, Disney XD, and Nicktoons). Visual branding was more common in children's advertisements vs. adult advertisements, with food packaging present in 88% vs. 23%, and street view of the QSR restaurant present in 41% vs. 12%. Toy premiums or giveaways were present in 69% vs. 1%, and movie tie-ins present in 55% vs. 14% of children's vs. adult advertisements. Median food image diagonal length was 20% of the advertisement diagonal for children's and 45% for adult advertisements. The audio script for children's advertisements emphasized giveaways and movie tie-ins whereas adult advertisements emphasized food taste, price and portion size.Children's QSR advertisements emphasized toy giveaways and movie tie-ins rather than food products. Self-regulatory pledges to focus on actual food products instead of toy premiums were not supported by this analysis.