Existence and uniqueness of almost periodic solutions for a class of nonlinear Duffing system with time-varying delays

In this paper, we investigate the existence and uniqueness of almost periodic solutions for a class of nonlinear Duffing system with time-varying delays. By using theory of exponential dichotomies and contraction mapping principle, we establish some new results and give an example to illustrate the theoretical analysis in this work

A CONCEPTUAL FRAMEWORK FOR MOBILE GROUP SUPPORT SYSTEMS

The rapid development of wireless communication and mobile devices has created a great opportunity to support mobile group coordination at a more efficient level than before. This article presents a framework for Mobile Group Support Systems (MGSS) that considers four dimensions: supporting whom, supporting what, where to support and how to support. A good MGSS design should take consideration with the characteristics of each dimension: the system should be able to support mobile users working jointly with members from multiple parties; using available and advanced mobile technology, the system should be able to support context freedom, context dependent, and ad hoc coordination under dynamic, uncertain, frequent disrupting, time and space stretched and fluid context. To meet these requirements, we discuss the issues related to three basic functions of MGSS: mobile communication, group coordination, and context awareness

赤身魚肉のミオグロビン還元機構に関する研究

Tohoku University落合芳博課

Engineering lanthipeptides by introducing a large variety of RiPP modifications to obtain new-to-nature bioactive peptides

Natural bioactive peptide discovery is a challenging and time-consuming process. However, advances in synthetic biology are providing promising new avenues in peptide engineering that allow for the design and production of a large variety of new-to-nature peptides with enhanced or new bioactivities, using known peptides as templates. Lanthipeptides are ribosomally synthesized and posttranslationally modified peptides (RiPPs). The modularity of post-translational modification (PTM) enzymes and ribosomal biosynthesis inherent to lanthipeptides enables their engineering and screening in a high-throughput manner. The field of RiPPs research is rapidly evolving, with many novel PTMs and their associated modification enzymes being identified and characterized. The modularity presented by these diverse and promiscuous modification enzymes has made them promising tools for further in vivo engineering of lanthipeptides, allowing for the diversification of their structures and activities. In this review, we explore the diverse modifications occurring in RiPPs and discuss the potential applications and feasibility of combining various modification enzymes for lanthipeptide engineering. We highlight the prospect of lanthipeptide- and RiPP-engineering to produce and screen novel peptides, including mimics of potent non-ribosomally produced antimicrobial peptides (NRPs) such as daptomycin, vancomycin, and teixobactin, which offer high therapeutic potential.</p