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The Curtin-Hammett principle, which works in a reaction sequence where slow irreversible reactions are connected to a fast reversible reaction, determines the product distribution depending only on the relative energy barriers of the two irreversible reactions, resulting in kinetic pathway selection. A basic question is how the reaction pathway is selected in reaction networks composed of reversible reactions to generate a metastable state. Numerical simulations of model systems where reversible elementary reactions are connected linearly to an initial reversible reaction demonstrate that a metastable state far from equilibrium is transiently produced and that its lifetime is prolonged by increasing the number of connected reversible reactions. The pathway selection in the model systems originates from quasi-irreversibility, and a similar behavior was also observed in the molecular self-assembly of a Pd₆L₄ truncated tetrahedron, which supports the idea that the emergence of quasi-irreversibility is a key general concept underlining kinetic control in reversible reaction networks.

This paper describes the state of the art of structural steel reuse in Japan. A significant part of the material is taken from a document titled the Architectural Institute of Japan (AIJ) Recommendations for Sustainable Steel Building Construction (Draft) available only in the Japanese language. The motivations for and potential benefits of steel reuse are examined. The affinity between seismic design requirements and steel reuse is highlighted through a concept known as damage-control design. Some technologies for disassembly are introduced. The historical development and changes in Japanese structural steel are summarized, followed by a discussion on reusability of historical steel reclaimed from existing buildings. Reuse projects whose details are known to the authors are listed. The heart of the paper is a design procedure that specifies the structural engineer's role and involvement in planning, material procurement, and executing a steel reuse project. The discussion is concluded by six directions that should be pursued to make steel reuse a widely accepted reality in Japan. Among those directions are research needs to establish a procedure to quantify the remaining structural performance of reclaimed steel considering possible exposure to earthquakes, establish connections that allow for easy disassembly, and introduce modularized structural systems. High seismicity and the general practice to adopt full moment frames pose unique challenges for steel reuse in Japan.

Peptides can be converted to highly active compounds by introducing appropriate substituents on the suitable amino acid residue. Although modifiable residues in peptides can be systematically identified by peptide scanning methodologies, there is no practical method for optimization at the scanned position. With the purpose of using derivatives not only for scanning but also as a starting point for further chemical functionalization, we herein report the scanning and direct derivatization strategy through chemoselective acylation of embedded threonine residues by a serine/threonine ligation (STL) with the help of in situ screening chemistry. We have applied this strategy to the optimization of the polymyxin antibiotics, which were selected as a model system to highlight the power of the rapid derivatization of active scanning derivatives. Using this approach, we explored the structure-activity relationships of the polymyxins and successfully prepared derivatives with activity against polymyxin-resistant bacteria and those with Pseudomonas aeruginosa selective antibacterial activity. This strategy opens up efficient structural exploration and further optimization of peptide sequences.

Vibrations emitted by smartphones have become a part of our daily lives. The vibrations can add various meanings to the information people obtain from the screen. Hence, it is worth understanding the perceptual transformation of vibration with ordinary devices to evaluate the possibility of enriched vibrotactile communication via smartphones. This study assessed the reproducibility of vibrotactile sensations via smartphone in the in-the-wild environment. To realize improved haptic design to communicate with smartphone users smoothly, we also focused on the moderation effects of the in-the-wild environments on the vibrotactile sensations: the physical specifications of mobile devices, the manner of device operation by users, and the personal traits of the users about the desire for touch. We conducted a Web-based in-the-wild experiment instead of a laboratory experiment to reproduce an environment as close to the daily lives of users as possible. Through a series of analyses, we revealed that users perceive the weight of vibration stimuli to be higher in sensation magnitude than intensity under identical conditions of vibration stimuli. We also showed that it is desirable to consider the moderation effects of the in-the-wild environments for realizing better tactile system design to maximize the impact of vibrotactile stimuli., Comment: 8 pages, 9 figures

In data science education, the importance of learning to solve real-world problems has been argued. However, there are two issues with this approach: (1) it is very costly to prepare multiple real-world problems (using real data) according to the learning objectives, and (2) the learner must suddenly tackle complex real-world problems immediately after learning from a textbook using ideal data. To solve these issues, this paper proposes data science teaching material that uses agent-based simulation (ABS). The proposed teaching material consists of an ABS model and an ABS story. To solve issue 1, the scenario of the problem can be changed according to the learning objectives by setting the appropriate parameters of the ABS model. To solve issue 2, the difficulty level of the tasks can be adjusted by changing the description in the ABS story. We show that, by using this teaching material, the learner can simulate the typical tasks performed by a data scientist in a step-by-step manner (causal inference, data understanding, hypothesis building, data collection, data wrangling, data analysis, and hypothesis testing). The teaching material described in this paper focuses on causal inference as the learning objectives and infectious diseases as the model theme for ABS, but ABS is used as a model to reproduce many types of social phenomena, and its range of expression is extremely wide. Therefore, we expect that the proposed teaching material will inspire the construction of teaching material for various objectives in data science education., Comment: 9 pages, 10 figures

Recently, electronic commerce (EC) websites have been unable to provide an identification number (user ID) for each transaction data entry because of privacy issues. Because most recommendation methods assume that all data are assigned a user ID, they cannot be applied to the data without user IDs. Recently, session-based recommendation (SBR) based on session information, which is short-term behavioral information of users, has been studied. A general SBR uses only information about the item of interest to make a recommendation (e.g., item ID for an EC site). Particularly in the case of EC sites, the data recorded include the name of the item being purchased, the price of the item, the category hierarchy, and the gender and region of the user. In this study, we define a pseudo--session for the purchase history data of an EC site without user IDs and session IDs. Finally, we propose an SBR with a co-guided heterogeneous hypergraph and globalgraph network plus, called CoHHGN+. The results show that our CoHHGN+ can recommend items with higher performance than other methods., Comment: 15 pages, 1 figures, 5 tables