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Abstract The effects of low-dose radiation on undifferentiated cells carry important implications. However, the effects on developing retinal cells remain unclear. Here, we analyzed the gene expression characteristics of neuronal organoids containing immature human retinal cells under low-dose radiation and predicted their changes. Developing retinal cells generated from human induced pluripotent stem cells (iPSCs) were irradiated with either 30 or 180 mGy on days 4–5 of development for 24 h. Genome-wide gene expression was observed until day 35. A knowledge-based pathway analysis algorithm revealed fluctuations in Rho signaling and many other pathways. After a month, the levels of an essential transcription factor of eye development, the proportion of paired box 6 (PAX6)-positive cells, and the proportion of retinal ganglion cell (RGC)-specific transcription factor POU class 4 homeobox 2 (POU4F2)-positive cells increased with 30 mGy of irradiation. In contrast, they decreased after 180 mGy of irradiation. Activation of the “development of neurons” pathway after 180 mGy indicated the dedifferentiation and development of other neural cells. Fluctuating effects after low-dose radiation exposure suggest that developing retinal cells employ hormesis and dedifferentiation mechanisms in response to stress.

Abstract Chemical-induced dysregulation of DNA methylation during the fetal period is known to contribute to developmental disorders or increase the risk of certain diseases later in life. In this study, we developed an iGEM (iPS cell-based global epigenetic modulation) detection assay using human induced pluripotent stem (hiPS) cells that express a fluorescently labeled methyl-CpG-binding domain (MBD), which enables a high-throughput screening of epigenetic teratogens/mutagens. 135 chemicals with known cardiotoxicity and carcinogenicity were categorized according to the MBD signal intensity, which reflects the degree of nuclear spatial distribution/concentration of DNA methylation. Further biological characterization through machine-learning analysis that integrated genome-wide DNA methylation, gene expression profiling, and knowledge-based pathway analysis revealed that chemicals with hyperactive MBD signals strongly associated their effects on DNA methylation and expression of genes involved in cell cycle and development. These results demonstrated that our MBD-based integrated analytical system is a powerful framework for detecting epigenetic compounds and providing mechanism insights of pharmaceutical development for sustainable human health.

While it has been proven that product development using crowdsourcing can produce highly marketable products, it continues to be a heavy burden to evaluate the large volume of user-generated ideas and to select the most attractive ones. In this study, we constructed a method that automatically measures novelty by constructing a conceptual space from crowdsourced ideas using natural language processing and calculating the rarity of opinions based on the statistical infrequency in the conceptual space. The method was applied to data obtained from a recipe submission site and the automatically measured novelty was shown to have validity in forecasting the attractiveness of recipes. The method developed in this study not only automated the evaluation of ideas, but also gave a new role as a material to construct a conceptual space for the majority of rejected ideas that had been neglected in the past, and gave these ideas new roles as the objects of research.

In the active material of a lithium-ion secondary battery, electrons and lithium-ions react at the same time. The fact that the active material can transfer electrons with a small reaction overvoltage leads to a reduction in the internal resistance of the battery. Therefore, when the electrical resistance was measured by changing the electrode material in contact with the active material, it was found that the electrical resistance of the active material was reduced depend on the carbon materials make contact with the active material.

The “Flutter-mill” is a power generation device that can be parallelized and downsized more easily than conventional wind-power generators with the added advantage of lower manufacturing costs. Flutter-mills comprise a flexible sheet with an electric power generator at its leading edge. Flutter-mills exhibit complex power generation performance characteristics that are highly dependent on the specifications of the flexible sheet and the inlet flow velocity. In particular, the span width of the sheet affects the stability and flapping behavior significantly. Using the numerical analysis model, these complex flutter-mill characteristics can be estimated without experiments, and thereby numerical model inform the choice of the sheet dimensions, which are critical for designing an effective flutter-mill. Here, we present a numerical model that can provide a preliminary survey of the power generation performance and attempt to clarify the relationship between the aspect ratio of the sheet and the harvested power. The equation of motion for a flexible sheet includes rotational damping at the leading edge of the sheet to emulate the coupling effect between the sheet and the energy harvesting circuit. We verified the validity of our numerical model by evaluating its performance against previously published experimental results, and thus established the relationship between the aspect ratio of the sheet and the harvested power. We found that the local minimum value of the harvested power of the flutter-mill may be caused by the vibration amplitude at the leading edge of the sheet decreasing in the transition domain of the flapping vibration mode if the aspect ratio is large.

Abstract We demonstrate physical implementation of information-theoretic secure oblivious transfer based on bounded observability using optical correlated randomness in semiconductor lasers driven by common random light broadcast over optical fibers. We demonstrate that the scheme can achieve one-out-of-two oblivious transfer with effective key generation rate of 110 kb/s. The results show that this scheme is a promising approach to achieve information-theoretic secure oblivious transfer over long distances for future applications of secure computation such as privacy-preserving database mining, auctions and electronic-voting.

Currently, personal mobility vehicles (PMVs) are attracting attention as intermediate- or short-range transportation. Bicycles are familiar PMVs that are also environmentally friendly and convenient. A small-wheel bicycle saves space and is easy to carry. However, a small-wheel bicycle running at low speed has poor upright stability and maneuverability. The purpose of this study is to improve its running stability by adopting a steer-by-wire system, which independently operates the steering gear and the tire. Sensors obtain the handle angle and actuators, instead of force from a mechanical connection, change the steering wheel angle. In this study, we carried out two experiments. First, we carried out straight running experiments to confirm the steering accuracy, upright stability, and maneuverability on a straight course. Second, we carried out turning experiments to confirm the upright stability and maneuverability on a course requiring changes in driving direction. It was confirmed that the proposed mechanism enhanced the upright stability compared with that of a conventional small-wheel bicycle. However, the maneuverability evaluations by the drivers showed that a conventional small wheel bicycle was better than the proposed steer-by-wire bicycle. The delay of motor control and the moment of inertia of the gearing might be the causes of this performance issue.

Stress in early life has been linked with the development of late-life neurological disorders. Early developmental age is potentially sensitive to several environmental chemicals such as alcohol, drugs, food contaminants, or air pollutants. The recent advances using three-dimensional neural sphere cultures derived from pluripotent stem cells have provided insights into the etiology of neurological diseases and new therapeutic strategies for assessing chemical safety. In this study, we investigated the neurodevelopmental effects of exposure to thalidomide (TMD); 2,2′,4,4′-tetrabromodiphenyl ether; bisphenol A; and 4-hydroxy-2,2′,3,4′,5,5′,6-heptachlorobiphenyl using a human embryonic stem cell (hESC)-derived sphere model. We exposed each chemical to the spheres and conducted a combinational analysis of global gene expression profiling using microarray at the early stage and morphological examination of neural differentiation at the later stage to understand the molecular events underlying the development of hESC-derived spheres. Among the four chemicals, TMD exposure especially influenced the differentiation of spheres into neuronal cells. Transcriptomic analysis and functional annotation identified specific genes that are TMD-induced and associated with ERK and synaptic signaling pathways. Computational network analysis predicted that TMD induced the expression of DNA-binding protein inhibitor ID2, which plays an important role in neuronal development. These findings provide direct evidence that early transcriptomic changes during differentiation of hESCs upon exposure to TMD influence neuronal development in the later stages.

Inverted pendulum vehicles controlled by movement of driver's center of gravity (COG), such as Winglet or Segway are the examples of Personal Mobility Vehicles (PMV). PMV is sometimes expected to be used in pedestrian spaces. When a driver brakes an inverted pendulum vehicle suddenly, the driver has to move his/her COG backward largely and has the risk to lose his/her balance due to the characteristics of vehicle control. Therefore, we aim to achieve a vehicle control system that is friendly to drivers in emergency. In the previous study, the coupling model of a vehicle and a human had been built on Multibody Dynamics and the technique to brake an inverted pendulum vehicle automatically had been proposed using that model. In this study, we carried out two experiments to decide the timing of the automatic braking system defined as Time To Collision (TTC). We carried out two experiments about stopping distance when a driver brakes an inverted pendulum vehicle suddenly and when the automatic braking system is operated, and we compared those results. Then, it was shown that stopping distance operated by the automatic braking system is shorter than by human driver's sudden braking operations. In addition, we derived TTC1 ( 0.7 s ) of inverted pendulum vehicles from these experiments about stopping distance by human drivers' sudden braking. Then, we derived reaction time ( 0.4 s ). Finally, we proposed a safety system using TTC1 and the reaction time. When TTC reaches 1.1[s], the alarm makes a human brake an inverted pendulum vehicle suddenly. Then if a human doesn't brake an inverted pendulum vehicle suddenly and TTC reaches 0.7[s], the automatic braking is operated.

Recently, probabilistic evaluation has been required in the seismic design. In this study, a design method of piping system supported by elasto-plastic damper based on dynamic reliability of pipings was proposed. First, an analytical model of an L-type cantilevered piping system with weight at the top end subjected to seismic input was derived, considering the nonlinear characteristics of the elasto-plastic dampers. Installation of a lead extrusion damper (LED) was assumed as the elasto-plastic damper. The force-displacement relationship of the LED was given by a bilinear hysteretic curve. Seismic input was modeled as white Gaussian noise. The vibration behaviors were calculated for various seismic inputs, and the stress and the energy absorption were calculated. On the basis of the results, the evaluation indices, such as the dynamic reliability, the energy absorption ratio, and the balance of energy absorption, were calculated. Finally, optimization of the support locations was investigated on the basis of the view point of the dynamic reliability. In addition, the effects of the capacities of the two supports on the evaluation index are also investigated. As a result, Jpiping was highest when Node 10 was supported at B. Jenergy was higher when Supports A and B were close to the weight but a little apart from each other. Jbalance was lower when Supports A and B were close to each other. Furthermore, it was obtained that the effect of Support B capacity on the response behavior of pipings is larger than that of Support A capacity.

From the view point of the environmental protection and convenience for transportation, a bicycle is one of the effective forms of the personal mobility vehicles. It is known that a small wheel bicycle running at low speed has less upright stability. In this study, Steer-by-Wire system is used to steer and stabilize a small wheel bicycle. In a bicycle with Steer-by-wire system, the mechanical connection between handlebar and steer-assembly is replaced by electronic connection with actuators, sensors and a controller. The system can enhance the upright stability of a bicycle by a control system. This study aims to enhance the upright stability of a small wheel bicycle at low speed. Firstly, we conducted the eigenvalue analysis to evaluate the upright stability of a bicycle and examined the difference of the stability between a bicycle with normal wheel and a small wheel one. Secondly, we designed the mechanism of Steer-by-Wire system and examined the effectiveness of Steer-by-Wire system in a small wheel bicycle. Finally, we investigated the behavior of a small wheel bicycle with Steer-by-Wire system when the system is subjected to disturbance torque. As a result, we found that Steer-by-Wire system could enhance the upright stability of a small wheel bicycle at a low speed.

In recent years, personal mobility vehicles (PMVs) have attracted huge attentions and widely developed. Compact PMVs can move through narrow spaces and they are expected to be used in pedestrian spaces. In this study, we aim to develop a four-wheel stand-up-type personal mobility vehicle for people who cannot walk far distantly because of the pain of foot or waist although they are able to walk for a short distance. The coupled model of human and vehicle is constructed by using multibody dynamics. In the model, the vehicle is expressed by one rigid body. The wheels, body, and handle are considered as a rigid body together. A human is expressed by 8 rigid bodies (foot, lower leg, femoral, body, head, upper arm, lower arm, and hand). The vehicle of the coupled model is accelerated in the numerical simulations. The behaviors of the center of gravity of a human with and without handle constraint are analyzed. As the result of the parametric study, it is found that the center of gravity movement is smaller when the value of the maximum acceleration and the acceleration time are small. It is also found that as the angle of the upper arm becomes large, the movement of the center of gravity is decreased.

This study reports about the numerical simulation of the sheet flutter in passage flow with large deformation and vortex shedding from trailing-edge. The equation of motion for flexible sheet has the Kelvin-Voigt-type material damping. Discrete vortices are shed to satisfy the regularity condition of flow at trailing-edge. At first, our numerical model under the uniform flow was compared with the preceding study to verify this model. Using the validated simulation model, we investigated the relationship among the material damping, width of passage and behavior of flutter. We clarified that material damping and passage width affect the flutter behavior and the efficiency of energy harvest due to flutter.

A flexible biomimetic fish-like robot for use in a flow in narrow passage was developed. Downsizing of the moving body was achieved using shape memory alloy (SMA) actuators. However, overheating an SMA actuator causes phase-transition saturation, and may cause a decrease in the fin vibration amplitude. In order to avoid this problem, a new driving method that utilized a self-excited oscillator was introduced. This proposed method is suited for generating oscillation with keeping temperature in SMA constant by using self-sensing, and needs to adjust only one parameter. We confirmed the effectiveness of the proposed driving method against overheating based on experiments and numerical simulations. Simulation proved that this method can keep thrust force of the moving body constant. For the fish-like moving body, multiple actuators are needed to realize higher degree of freedom behavior, and the phases of these actuator outputs also are needed to be synchronized to generate fish-like behavior, i.e., traveling wave. On the other hand, in the proposed driving method, the actuator system simulates a self-excited vibration system. Therefore, it was necessary to design the coupled inputs for oscillators composed by actuators to synchronize the oscillator outputs. To achieve this, a phase model was obtained from an actuator model, which consists of a thermal conductivity model and hysteresis model using a phase reduction analysis. Coupled inputs for proposed connecting method were designed based on this phase model, and the relationship between the phase difference of the coupled actuators and the connection gains was examined. Finally, we realized phase control using this.

Background: Suplatast tosilate is a type 2 (Th2) cytokine inhibitor that blocks the production of IgE antibodies and the invasion of tissues by eosinophils during an allergic reaction. Suplatast tosilate ameliorates asthma symptoms and airway hypersensitivity by inhibiting production of the Th2 cytokines interleukin (IL)-4 and IL-5. Methods: In the present study, a comparative examination of the therapeutic effects of suplatast tosilate was carried out in patients with mild intermittent and mild persistent asthma by randomly allocating 35 adult patients to a suplatast tosilate group (n = 18 ; 100 mg suplatast tosilate three times daily) and a beclomethasone dipropionate (BDP) group (n = 17; 200 μg BDP twice daily) for 6 weeks of treatment. Results: The suplatast tosilate group required more time than the BDP group to show improvement in peak expiratory flow, but at week 6 the change from baseline was nearly the same in both groups. A significant improvement was observed for both groups in the peripheral blood eosinophil ratio, serum eosinophil cationic protein (ECP) levels, induced sputum ECP levels, forced expiratory volume in 1 second, and airway hypersensitivity, but induced sputum ECP level was lower in the BDP group than in the suplatast tosilate group. Total IgE levels decreased in the suplatast tosilate group only. Conclusions: We conclude that suplatast tosilate may be useful inlong-term management of mild bronchial asthma.

Authors developed the flexible biomimetic fish-like robot for usage in narrow passage flow. The robot mainly consists of three sections: a control section, actuator section and flexible fin section. By using the shape memory alloy (SMA) actuators, downsizing and lightening has been achieved. At first, we constructed the fluid-body coupled model of robot fish for consideration of undulatory swimming and nonlinearity of SMA characteristics. We also constructed experimental model to confirm the validity of analytical model. It is known that dynamics of SMA actuator depends on ambient temperature. Therefore over-heating of SMA actuator may cause accumulation of heat in actuator section of the moving body, and decrease of the amplitude of the caudal fin and the thrust force. Thus, in this study, to improve the driving characteristics of actuator, we identified the relation between temperature and moment of SMA actuator. Next, we constructed the fluid-moving body interaction model which is considering the dynamics of actuator. We searched the local optimal input for SMA actuator based on optimization theory. As a result, it was found that for maintaining high thrust force SMA actuator needs to be driven keeping the temperature around 340[K].

Sit-to-stand (STS) rehabilitation equipment traditionally simulates natural movements of unspecified healthy people. This type of movement may not place the lowest load on a patient's body. These factors let us develop a novel and widely applicable system for rehabilitation purposes that suggests a motion that places low body loads at the lower limb joints. This paper describes the core computation in the system that calculates a STS movement that places a minimum body load by using Continuous Genetic Algorithm (CGA). The minimization process starts from measurement of kinematic and kinetic data of a human subject by using gyroscopic sensors and reaction force plates, and then estimation and evaluation of the body load are followed. The body load which is minimized during STS movement was quantified by an index value. The index value strongly correlates with the chair height. Decreasing this index value by changing the movement during STS transfer could reduce the impact on the body, which is the same amount of load placed on the body while standing up from a higher chair height. The angular displacements of the averaged natural STS movement of the subject were considered as one of the several ways to stand up and the movements were assessed by means of the index value in CGA. A modified STS movement that can minimize the body load was computed after the optimization and it could be a personalized optimum movement allowing users to conduct rehabilitation with lesser unnecessary body load.

Many epidemiological and animal exposure studies have suggested that exposure to environmental substances is a major risk factor for developmental neurotoxicity (DNT), such as in autism, and is related to the increasing relevance of neurodevelopmental disorders. Recent efforts have led to the development of various in vitro approaches that use cell lines and pluripotent stem cells to assess numerous environmental substances. In this study, we developed a method for assessing DNT using a mouse embryonic stem (mES) cell model that focuses on differentiation into neuronal cells (neural cells and astrocytes). Using this model system, we found that six insecticides inhibited the differentiation of neural precursor cells into astrocytes. Our data indicated that the effects of insecticides on glial differentiation were more sensitive than those of several DNT markers reported in previous studies. This mES cell model can make a quick assessment of DNT potential and may be a useful tool for screening substances with potential to induce DNT. [ABSTRACT FROM AUTHOR]