In a post-growth multicellular organism, the phenomenon in which a small number of rare cells can be the starting point for inducing a dramatic change in the entire system is considered a “biological

.” The immune response and cancer can be regarded as phenomena in mammals, but their nature is fundamentally different. The immune response is considered a “programmed” , whereas cancer is an “unprogrammed” . These two systems perpetually engage in a cycle of attack and defense within the organism. The outcome is depending on the wining system, which determines whether the individual experiences a state resembling light or darkness. However, the overall mechanism of the competition remains unclear and is expected to be elucidated with future innovations in bioimaging technologies. Immune checkpoint blockade therapy is a means by which the two balances can be artificially manipulated; therefore, mechanistic insight is necessary for cancer treatment strategies. Altogether, these findings provide a different perspective crucial for understanding the behavior of dynamic cell populations in multicellular organisms.

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phenomena are rare events that occur only with a probability of one in tens of thousands and yet play an important role in the fate of the entire system. Recently, an ultra-wide-field microscopy imaging systems, AMATERAS, have been developed to reliably capture phenomena. However, to determine whether a rare phenomenon captured by microscopy is a true phenomenon—one with a significant impact on the entire system—, causal analysis is required. In this section, we introduce the CALI method, which uses light to inactivate molecules as one of the techniques enabling causal analysis. In addition, we discuss the technical innovations of the CALI method that are required to contribute to the future development of biology.

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Much attention has been paid on CMGs (Control Moment Gyros) as a large torque generator of spacecraft. There are many studies on singularities of CMGs. However, the steering law in their studies has achieved only

avoidance in most cases. In this paper, we propose a multi-objective steering law which achieves complete 3-axis attitude control while considering not only avoidance but also another function. First, we introduce a steering law for both avoidance and power optimization. Second, we propose another steering law for both avoidance and achieving preferred gimbal angles. Regarding the control law, we apply a GS (Gain-Scheduled) controller via LPV control theory while introducing a Parameter-Dependent Coordinate Transformation.

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Singular configurations must be avoided in the practical manipulation of parallel mechanism. This paper presents an approach of singularities analysis of six degrees of freedom (DOF) parallel mechanism applying geometric algebra. Twists of all passive joints in each limb are described in geometric algebra while all the active joints are locked. And wrenches produced from each limb and acting on the moving platform are derived from the calculations of the outer product and its dual of the corresponding twists. The singular condition of parallel mechanism depends on whether the wrenches acting on the moving platform failed to constrain all the motions, which can be accomplished by the outer product with its duality followed. Two six-DOF parallel mechanisms 6-UPS and 6-PUS are introduced to verify the approach proposed in this paper. The results indicate that geometric algebra can also be used for

analysis of six-DOF parallel mechanism.

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A mismatch in material properties may cause a stress , which leads to the failure of bonding in joints. It is important to analyze the stress field for evaluating the strength of the interface in three-dimensional joints. Thermal residual stresses occur in a cooling process after bonding the joints at a high temperature, and the stress for thermal stresses also occurs at an interface corner in the joints. In the present paper, a boundary element method and an eigenvalue analysis formulated using a finite element method are used for evaluating the intensity of of the residual thermal stresses at a vertex in a joint. A three-dimensional boundary element program based on the fundamental solution for a two-phase isotropic body is used. The singular stress field for residual thermal stresses at the vertex in three-dimensional bonded structures with an interlayer is analyzed while varying the material properties of the interlayer. In addition, the relationship between Dundurs' parameter for three-dimensional stress states and the intensity of is derived. In the present study, the stress field is estimated for an arbitrary material combination investigated using this relationship under thermal loadings.

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In this paper, a novel method for automatic identification of a surgical operation and on-line recognition of the of the identified surgical operation is proposed. Suturing is divided into six operations. The features of the operation are extracted from the measurements of the movement of the forceps, and then, on the basis of the threshold criteria for the six operations, a surgical operation is identified as one of the six operations. Next, the features of any of operation are extracted from operator's surface electromyogram signals, and the identified surgical operation is classified as either normal or singular using a self-organizing map. Using the built laparoscopic-surgery simulator with two forceps, the identification of each surgical operation and the distinction of the of the identified surgical operation were carried out for a specific surgical operation, namely, insertion of a needle during suturing. Each surgical operation in suturing could be identified with more than 80% accuracy, and the of the surgical operation of insertion could be distinguished with approximately 80% accuracy on an average. The experimental results showed the effectiveness of the proposed method.

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In this study, the enriched finite element method (enriched FEM) is applied to evaluate the intensity of for three-material joints with power-logarithmic singularities. Using this method, the intensity of singularities can be directly evaluated and very refined meshes around the singular point are unnecessary. Analyses for eigenvalue and eigenvector are conducted to calculate the order of stress singularities and the asymptotic displacement fields on the enriched elements. Accuracy of the results for different mesh types (4-node and 8-node elements) and different sizes of the enriched region are compared with the value obtained from extrapolation for stress distribution based on FEM with very fine mesh. Finally, the models with various lengths and thicknesses are investigated to study an influence of geometry on the singular stress field.

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Dissimilar material properties may cause stress singularities, which may lead to the failure of the bonding part in joints. It is important to analyze stress fields in order to evaluate the strength of the interface in three-dimensional joints. Thermal residual stresses occur during cooling after bonding of the joints, and stress singularities can also be caused by these thermal stresses. In the present study, a boundary element method and an eigenvalue analysis based on the finite element method are used to evaluate the intensity of the stress . A three-dimensional boundary element program based on the fundamental solution for two-phase isotropic materials is used. The strength of the interface of two types of Si-resin specimens with different bonding areas is investigated analytically and experimentally. Stress analysis is first carried out for a delamination force acting on the specimen. The stress field for the residual stresses is determined while varying the material property in resin with temperature. Combining the stress field for the delamination force and the residual thermal stress yields a final stress distribution for evaluating the strength of the interface. Finally, the strength of the interface in three-dimensional joints was determined as 0.0914-0.133 MPa·m^0.68.

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The expectation value of the quantum stress tensor for the massless scalar field on the classical background of spherical dust collapse is considered. The results show that the back reaction does not become important during the semiclassical phase.

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In this paper, we will consider the blowup and the time-global existence of radial solutions to a simplified system of the so called Keller-Segel model in a domain of three or more dimensional Euclidean space. In the two dimensional case, the blowup solutions have a delta function at each blowup point (see [13]). However, in the three dimensional case, Herrero, Medina and Velázquez [7] show that there exist self-similar blowup solutions and that the solutions have a which is different from a delta function . In this paper, we will consider the blowup criterion and the blowup self-similar solutions in the three or more dimensional cases.

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Parallel robots with closed-loop kinematic chains have been used in industrial applications. They exhibit superior precision, stiffness, and operating speed than serial robots owing to their mechanical architecture. However, parallel robots demonstrate static

unique to parallel mechanisms, which further impede their application. Static is caused by passive joints included in the mechanism. In this study, a 3-leg 6-DOF spatial parallel robot with actuation redundancy and its statics are analyzed. The analysis indicates that static does not occur if actuation redundancy is properly introduced. This analysis is based on the decomposition of force transmission in the robot. Experimental results show that precise trajectory tracking and stable contact are achieved by virtue of the actuation redundancy. This study opens new avenues for the application of parallel robots.

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Stress is usually observed in practical stress analysis, and it may lead to the deterioration of the convergence rate of the preconditioned conjugate gradient method (PCG). Until now, parallel PCG has been used without considering the practical issues; therefore, the deterioration was induced in the problem in which stress was observed. The convergence acceleration method was developed in parallel PCG based on controlled domain decomposition. The acceleration method can be achieved by considering the spatial locality of stress and preconditioning of conjugate gradient method. The convergence acceleration method reduces the 15% of iteration of PCG as a maximum, where the singular area is included in one domain.

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This paper concerns kinematics and dimensional synthesis of a three universal-revolute-universal (3-URU) pure rotational parallel mechanism. The mechanism is composed of a base, a platform and three symmetric limbs consisting of U-R-U joints. This mechanism is a spatial non-overconstrained mechanism with three degrees of freedom. The joints in each limb are so arranged to perform pure rotational motion of the platform around a specific point. Equations for inverse displacement analysis and singularities were derived to investigate the relationship of the kinematic constants to the solution of the inverse kinematics and singularities. Based on the results, a dimensional synthesis procedure for the 3-URU parallel mechanism considering singularities and the workspace was proposed. A numerical example was also presented to illustrate the synthesis method.

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We discuss a kinematic design of a 3-5R translational parallel mechanism with a large utility workspace. The utility workspace is a closed area, in which the mechanism can move to point without suffering from singularities or running into workspace boundaries. An algorithm for computing the volume of the utility workspace is proposed. We discuss the utility workspace of 3-5R translational parallel mechanisms having three types of chain in consideration of their actuation and constraint singularities. We obtained a 3-RUU translational parallel mechanism with a large utility workspace.

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