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This study aimed to detect the behavior of cultivated cells such as cell differentiation via the surface wettability. The surface wettability on cultivated cells was assessed by air-jet based liquid squeezing method, where the liquid squeezed diameter was used for an index of surface wettability. The wettability of normal mouse skeletal myoblast cell line C2C12 was lower than that of myogenic-differentiated C2C12 cells. This result suggested a potential to detect cell differentiation via surface wettability.

The importance of collaborative studies between the fields of biology and engineering are increasing. Technological innovation is a primary driver of advances in molecular and cellular biology. Unfortunately, most cutting-edge technologies are difficult to practically apply to biology. In embryogenesis, biological systems show a high degree of spatially controlled differentiation patterns. To understand underpinning mechanisms of spatial differentiation patterns of human mesenchymal stem cells (hMSCs) quantitatively in an in vitro system, both advanced micro-fabrication and image analysis technologies are required. hMSC differentiation patterns induced here by the cultivation of cells in confined space and by exposing them to differentiation induction media. This paper discusses an ensemble of nonadhesive agarose micro cell-culture wells (microwells) confining cells on adhesive substrates and artificial intelligence (AI) to understand why hMSC do not differentiate homogeneously, but in patterns, from the viewpoint of usability of our technological advances in actual high throughput screening experiments.

This paper reports a light controllable single cell driven micro rotary vane pump for transport fluid in small space based on a new type of bio-actuator: Euglena. Different from other types of bio-actuators, Euglena has features of both animals and plants, which will allow, for the first time, bio-actuator functioned in fresh and salt water and take nourishment through photosynthesis. To demonstrate the potential of Euglena actuator, we fabricated a simple chamber as a pump structure, and let the Euglena swim through the chamber. Then, by irradiating the Euglena with light in a range from 400 to 420 nm, the Euglena started a fixed location-rotation, which generated a flow. The particles flow by the generated flow was confirmed.

This paper proposes a compressive sensing method for the phased array weather radar (PAWR), which is capable of three-dimensional observation with high spatial resolution in 30 seconds. Because of the large amount of observation data, which is more than 1 gigabyte per minute, data compression is an essential technology to operate PAWR in the real world. Even though many conventional studies applied compressive sensing (CS) to weather radar measurements, their reconstruction quality should be further improved. To this end, we define a new cost function that expresses prior knowledge about weather radar measurements, i.e., local similarities. Since the cost function is convex, we can derive an efficient algorithm based on the so-called convex optimization techniques, in particular simultaneous direction method of multipliers (SDMM). Simulation results show that the proposed method outperforms the conventional methods for real observation data with improvement of 4% in the normalized error.

This study developed agarose micro casts for the analysis of patterned differentiation of mesenchymal stem cells (hMSCs). The patterned differentiation of hMSCs was observed in agarose micro cast wall. The stained image of hMSCs was automatically analyzed.

Our proposed architecture of dynamically reconfigurable hardware for protocol processing (DRHPP) provides flexibility with high area efficiency. It can be used for a communications system-on-a-chip (SoC) in access networks. The DRHPP enables the modification and addition of various functions for protocol processing. Our architecture consists of three types of cells. The optimized number of these types of cells for the intended protocol processing can be implemented for increasing cell utilization, which can decrease the total area. Additionally, the best granularity for the cell also contributes to a decrease of the total area. We implemented a protocol-processing circuit using DRHPP for protocol-frame parser processing. Implementation results show the proposed architecture improves flexibility with only a 33% area penalty in comparison with a hard-wired protocol-processing circuit.

This study fabricated patterned cell culture system with a self-assembled bubble-raft created on a general cell-culture medium. The bubble raft was composed of bubbles generated by bubbling. After cells were seeded on the bubble raft, the cells were trapped in a gap between adjacent bubbles. The pattern of adherent cells were obtained within 2 h after the cell seeding.

This study assessed the wettability of cellular surface with noncontact meniscus manipulation under a microscope. The surface of culture medium covered on cells was manipulated by air-jet and the meniscus of culture medium was generated. The movement of meniscus was monitored with a microscope. The shape of interface between culture medium and air on the cells was different from the part of cells.

A social robot, which is used in a human living environment, is gathering a massive attract from not only robot researchers but also the general people. Because the users of a social robot normally differ from the specialist of robotics, the robot is required to be controlled by an intuitive user-interface. An eye-gaze point is a good signal representing human-intention with interest as compared with other human behavior, such as indication by fingers or hand, gesture, voice, etc. Within this concept, a robot has successfully found human-intention even in experimental environment, human and robot has different point/angle view to the object.

This study performed multiple micro-contact printing of extra-cellular matrix with a fine alignment system for the position and the posture of polydimethylsiloxane (PDMS) stamp. The position and the posture were adjusted with a 4-axis automated stage with a resolution of 1 μm or 0.0025 deg. The adjustment was achived by monitoring the surface shape of PDMS stamp measured by using a laser displacement sensor in the alignment system. After the adjustment, fluorescent-dye-conjugated fibronectin applied on the surface of PDMS stamp was printed onto a cell culture dish. As the result of multiple printing, two different patterns of fibronectin were located on the same dish within an error of 50 μm.

PIPAAm grafted polystyrene (PIPAAm-Pst) dishes were prepared using visible light irradiation and polystyrene dishes modified with thioxanethone-based photoinitiator. At optimized preparation conditions, PIPAAm-PSs fabricating cell sheets were successfully prepared by 5 mins visible light irradiation. After PIPAAm polymerization, micro-patterned temperature responsive polystyrene culture surface (MPTRCS) were generated by additional micro-patterned polymerization of PAAm. Endothelial cells were attached selectively PIPAAm region at 37°C. By lowing temperature, micro-pattered endothelial cells were detached from MPTRCS as continuously micro-pattered cell sheet.

Verification of the hardware/software functions of a 10-Gbit/s-class large-scale network systems-on-a-chip (NW SoC) requires the use of multiple field programmable gate array (FPGA) devices. We propose two schemes for the efficient mapping of the design data of the NW SoC into FPGA devices. We implemented practical NW SoC design data for FPGA devices, and evaluated the effectiveness of the schemes. The results show that the proposed schemes can reduce the number of wires by 13% and improve the register access cycle time by 28%.

Regenerative medicine is getting popular all over the world. Especially, cell sheets for damaged corneal epithelium are expected to be commercially available in the near future. In cell culture procedure, the assessments of viability and tolerability of cell sheet are important. To date, the qualitative assessments have been performed by specialists without any quantitative evaluation. This study attempted to evaluate the wetting characteristic of cell sheet quantitatively and noninvasively as much as possible. There are three points to be considered; (1) cell sheet is susceptible to dry, (2) is free from a contamination, and (3) is thin with a thickness of less than 100 μm. Under these constraints, a non-contact evaluation system with both an air-jet application and an optical observation units was newly developed. This study found that there is a significant difference in the wetting characteristics of cell sheets in different culture conditions.

This paper presents a software-hardware co-operative protocol processor for a 10 gigabit Ethernet passive optical network (10G-EPON), designed with a software-hardware division technique that focuses on the throughput and timing-accuracy requirements. This protocol processor consists of frame-processing hardware to meet the timing requirements, an interface to absorb the speed difference between software and hardware, and software to implement additional protocols. This protocol processor enables network operators to install additional service protocols adaptively for their own services. The 10G-EPON system with this protocol processor properly worked in the experiment.

Non-contact stiffness sensor is often utilized especially for medical fields due to its advantage of avoiding damage to tissues and keeping sanitary. However, it is hard to measure the force accurately, because the fluid jet based force much depends upon the shape after deformation of object. This paper proposes an innovative approach where the external force is adaptively calibrated based on the deformation of object so that we can evaluate the internal stiffness parameters more accurately than that of conventional approaches. It is shown that the proposed method can improve the accuracy of force application with even 100% at an extreme case.

This paper discusses an inverse problem where internal stiffness parameters are determined by both applied force and deformation of object. By supposing a soft tissue, we first propose the simplest tissue model that can express the coupling effect where the tissue deforms not only at the point of force application but also its surrounding area. We explain the way for determining the internal stiffness parameters for the proposed model and show that we can nicely reconstruct the deformation of tissue, even for the sensing condition where we can utilize only point force and point deformation.

Stiffness could be an important index for evaluating the vitality of cell sheet. This paper challenges the measurement of stiffness of transparent cell sheet in culture liquid without taking it out from petri dish. The system is composed of a micro air nozzle for supplying an air jet and a regular reflective type laser sensor for measuring the the deformation of transparent cell sheet. This system is called as Cell Sheet Stiffness Sensing system (CS(3) system). When an air jet is given to a cell sheet in culture liquid, it pushes away the liquid toward the outer direction at initial phase and reaches the surface of cell sheet. Without any switching motion, the air jet continuously imparts a force to the surface of cell sheet so that the sensor can measure the stiffness of the cell sheet.

This paper discusses active sensing for detecting viscoelastic parameters of living tissues with the coupling effect among neighbors. Supposing that both applied force and surface deformation of tissue are known with respect to time, we obtain viscoelastic parameters of living tissue by utilizing a single layered model with horizontal and vertical units where each unit is composed of both stiffness and damping elements. We show that the model with only appropriate number of units can nicely express the dynamic characteristic of human skin.

This paper discusses the direction dependent response of human skin under the high speed force impartment with the range of speed of 1 m/s. Under such a dynamic condition, it is well known that human skin deformation can not modeled as a linear system, such as a combination of linear spring, linear damper, and mass. But it has different parameters between the force applying and the recovery phases. By observing the deformation through a high speed camera, we newly found that the direction dependent response comes from the different deformation mechanism between phases.

This paper discusses the Skin Surface Shock Wave which is generated after we impart an impulsive force to human skin. The force is given by an air jet during 200 [ms]. The basic behavior of shock wave is measured by a high speed camera with the frame rate of 2000 [Hz]. Through the experiment, we found an interesting behavior where there exists a remarkable difference between young and elder subjects especially during the recovery phase, while there is nearly no difference between two during the force imparting phase.

This paper proposes a new non-contact impedance imager based on phase differential technique enabling an enhanced detection of the existence of a tumor in tissues. The developed sensor is composed of an air supply system and two optical fiber based distance sensors next to the air nozzle. For a periodic air pressure, two distance sensors provide us with sinusoidal outputs with individual phases. The phase difference varies according to the change of impedance parameters of tissues between two points. A big advantage of the sensor is that the sensor can work irrespective of the color of tissues. Toward the implementation into human lung, the impedance parameters are measured for lung in vitro by using the developed sensor

The authors describe a mixed mode circuit simulator called SPLIT2. They suggest a dynamic network separation technique based on the tightness of the coupling between subnetworks at the level of the Newton-Raphson stage. First, the dynamic network separation algorithm is described. Next, this algorithm is introduced into the simulator SPLIT with hierarchical decomposition and latency. The validity of this mixed mode circuit simulator SPLIT2 is verified. SPLIT2 can select the direct method or the relaxation method and determine the block size of the latent circuit dynamically by using dynamic network partitioning. >

For efficient circuit simulation, several network tearing techniques have been studied. The authors describe a hierarchical decomposition system, HIDE, and verify its availability for the network solution by the direct method. This system has a graphic circuit editor, GRACE, a translator, LINKER, into the hierarchical structural description language HAL, and the subsystem HiDe, which performs automatic partition of the circuit into gate level subcircuits hierarchically, utilizing the HAL netlist. The authors discuss the hierarchical tearing algorithm for large scale circuits. The authors apply this system to transistor-transistor-logic (TTL) and MOS circuits and verify its availability for the matrix solution. >