We present a new network model accounting for multidimensional assortativity. Each node is characterized by a number of features and the probability of a link between two nodes depends on common features. We do not fix a priori the total number of possible features. The bipartite network of the nodes and the features evolves according to a stochastic dynamics that depends on three parameters that respectively regulate the preferential attachment in the transmission of the features to the nodes, the number of new features per node, and the power-law behavior of the total number of observed features. Our model also takes into account a mechanism of triadic closure. We provide theoretical results and statistical estimators for the parameters of the model. We validate our approach by means of simulations and an empirical analysis of a network of scientific collaborations.

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Confidentiality is a fundamental duty of a physician to maintain a safe medical system. The authors are law researchers and medical researchers. We planned interdisciplinary workshops including both legal and medical viewpoints. Encouraging medical students to understand the importance of confidentiality and its exceptions, we studied others' academic fields together over eight years, and established a fixed style of scenario-based group discussions. As a unique characteristic of this project, it includes actual students of law and other fields as facilitators to encourage mobility and circulation among disciplines. The workshop has continued since 2009, once a year. Results of student evaluations show their enhanced understanding of confidentiality as a core value of safety and sustainable medical systems. Other teaching purposes have mostly succeeded. Facilitators regard this workshop as a good opportunity to explore interdisciplinary studies as well. That interest maintains and reinforces the close relationship between these disciplines of study. Therefore, the authors conclude that this innovative workshop is very effective.

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We show that every matrix all of whose entries are in a fixed subgroup of the group of units of a commutative ring with identity is equivalent to a standard form. As a consequence, we improve the proof of Theorem 5 in D. Best, H. Kharaghani, H. Ramp [Disc. Math. 313 (2013), 855–864].

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We have developed a cryopreservation method that uses a single-component super-adiabatic two-fluid de Laval nozzle for the continuous production of solid nitrogen particles with a micro-nano-order particle size. The cell viability results showed that use of the solid nitrogen spray improved cell viability at the time of thawing by more than 20% compared with the conventional liquid nitrogen immersion freezing method. By using the present dynamic spray cooling method that avails of the synergistic effect of impingement heat transfer, convective heat transfer, and evaporation latent heat transfer of solid nitrogen particles, the new vitrification method reduces the cell membrane disruption caused by ice nucleation, crystal growth, and volume expansion.

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A connected graph is said to be of QE class if it admits a quadratic embedding in a Hilbert space, or equivalently if the distance matrix is conditionally negative definite, or equivalently if the quadratic embedding constant (QEC) of a graph is non-positive. The QEC of wheel graphs are calculated explicitly.

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Recent studies have demonstrated that a new association between auditory sequence and visual motion can be rapidly formed even in adults (sound-contingent visual motion perception: SCVM). The present study investigated the neural mechanisms underlying SCVM using event-related potential (ERP). During a 9-min exposure phase, two circles placed side-by-side were alternately and repeatedly presented to produce horizontal apparent motion. The onsets of the circles were synchronized with high- and low-frequency tones. ERPs were measured before and after the exposure phase in response to a pair of visual stimuli (S1 and S2) sequentially presented at a fixed location with a sound sequence that contained the same high and low frequency tones as presented during the exposure phase. After the exposure, the participants experienced SCVM. Significant ERP differences between the pre- and post-exposure were observed not only in the S2 presentation, but also in the S1 presentation. These findings suggest that SCVM processing starts in higher stages of the visual system as early as S1 presentation and then sends feedback signals to earlier stages to induce motion perception at S2 presentation.

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