Surjective isometries on an algebra of analytic functions with CnC^n-boundary values (Research on preserver problems on Banach algebras and related topics)

Let , ⁻ and be the open unit disk, closed unit disk and unit circle in ℂ. Let $A^n$(⁻) denote the algebra of all continuous functions f on ⁻ which are analytic in and whose restrictions f| to T are of class $C^n$. For each f ∈ $A^n$(⁻), the k-th derivative of f| as a function on is denoted by D^k(f). We characterize surjective, not necessarily linear, isometries on $A^n$(⁻) with respect to the norm ∥f∥⁻ + Σ[n][k=1]∥$D^k$(f)∥/k!, where ∥ · ∥⁻ and ∥ · ∥ are the supremum norms on ⁻ and , respectively

Mid-career pitfall of consecutive success in science

The creativity of scientists often manifests as localized hot streaks of significant success. Understanding the underlying mechanisms of these influential phases can enhance the effectiveness of support systems and funding allocation, fostering groundbreaking discoveries worthy of accolades. Historically, analyses have suggested that hot streaks occur randomly over time. However, our research, through meticulous examination, reveals that these phases are not flatly distributed but are more frequent at the early and late stages of scientists' careers. Notably, both early and late hot streaks are marked by dense tie collaborations, with the former typically involving close partnerships with particular authors and the latter being characterized by involvement in large-scale projects compared with single-top or ordinary papers. This pattern indicates that mid-career researchers lack both intimate relations and resources to keep big projects, leading to``mid-career pitfal'' of consecutive success. This insight holds profound implications for the development of policies and initiatives aimed at bolstering innovative research and discovery.Comment: 23 pages, 20 figure

スピロ[3.5]ノナン骨格含有メロテルペノイドCryptolaevilactone類およびモデル化合物の全合成研究

13301甲第5559号博士（創薬科学）金沢大学博士論文要旨Abstract 以下に掲載：Chem. Pharm. Bull 70(10) pp.740-747 2022. 日本薬学会. 共著者：Yuta Miura, Yohei Saito, Kyoko Nakagawa-Got

Anti-Allergic Activity of Monoacylated Ascorbic Acid 2-Glucosides

2-O-α-D-Glucopyranosyl-L-ascorbic acid (AA-2G) is one of the stable ascorbic acid (AA) derivatives known as provitamin C agents. We have previously synthesized two types of monoacylated derivatives of AA-2G, 6-O-acyl-2-O-α-D-glucopyranosyl-L-ascorbic acids having a straight-acyl chain of varying length from C4 to C18 (6-sAcyl-AA-2G) and a branched-acyl chain of varying length from C6 to C16 (6-bAcyl-AA-2G) in order to improve the bioavailability of AA-2G. In this study, 6-sAcyl-AA-2G and 6-bAcyl-AA-2G per se showed the inhibitory effects on hyaluronidase activity and degranulation. 6-sAcyl-AA-2G exhibited strong inhibitory effects on hyaluronidase activity and degranulation in a concentration-dependent manner, and the inhibitory effects tended to become stronger with increasing length of the acyl chain. 2-O-α-D-Glucopyranosyl-6-O-hexadecanoyl-L-ascorbic acid (6-sPalm-AA-2G), which has a straight C16 acyl chain, was the most potent effective for inhibition of hyaluronidase activity and for inhibition of degranulation among the 6-sAcyl-AA-2G derivatives and the two isomers of 6-sPalm-AA-2G. Furthermore, percutaneous administration of 6-sPalm-AA-2G significantly inhibited IgE-mediated passive cutaneous anaphylaxis reaction in mice. These findings suggest that 6-sPalm-AA-2G will be useful for treatment of allergies

Surjective isometries between unitary sets of unital JB∗-algebras

We would like to thank Prof. Lajos Molnár for encouraging us to explore this problem. We are also indebted to the anonymous reviewer for several useful comments. First and fifth authors partially supported by the Spanish Ministry of Science, Innovation and Universities (MICINN) and European Regional Development Fund project no. PGC2018-093332-B-I00, Programa Operativo FEDER 2014-2020 and Consejería de Economía y Conocimiento de la Junta de Andalucía grant numbers A-FQM-242-UGR18 and FQM375. First author partially supported by EPSRC (UK) project “Jordan Algebras, Finsler Geometry and Dynamics” ref. no. EP/R044228/1. Second author partially supported by JSPS KAKENHI Grant Number JP 21J21512. Fourth author partially supported by JSPS KAKENHI (Japan) Grant Number JP 20K03650. * Funding for open access charge: Universidad de Granada / CBUAThis paper is, in a first stage, devoted to establishing a topological–algebraic characterization of the principal component, U0(M), of the set of unitary elements, U(M), in a unital JB⁎-algebra M. We arrive to the conclusion that, as in the case of unital C⁎-algebras, U0(M)=M1−1∩U(M)={Ue⋯Ue(1):n∈N,hj∈Msa∀1≤j≤n}={u∈U(M): there exists w∈U0(M) with ‖u−w‖<2} is analytically arcwise connected. Actually, U0(M) is the smallest quadratic subset of U(M) containing the set eiM. Our second goal is to provide a complete description of the surjective isometries between the principal components of two unital JB⁎-algebras M and N. Contrary to the case of unital C⁎-algebras, we shall deduce the existence of connected components in U(M) which are not isometric as metric spaces. We shall also establish necessary and sufficient conditions to guarantee that a surjective isometry Δ:U(M)→U(N) admits an extension to a surjective linear isometry between M and N, a conclusion which is not always true. Among the consequences it is proved that M and N are Jordan ⁎-isomorphic if, and only if, their principal components are isometric as metric spaces if, and only if, there exists a surjective isometry Δ:U(M)→U(N) mapping the unit of M to an element in U0(N). These results provide an extension to the setting of unital JB⁎-algebras of the results obtained by O. Hatori for unital C⁎-algebras.CBUAConsejería de Economía y Conocimiento de la Junta de Andalucía A-FQM-242-UGR18, FQM375Ministerio de Ciencia, Innovación y UniversidadesEngineering and Physical Sciences Research Council EP/R044228/1Universidad de GranadaMinisterio de Ciencia e InnovaciónJapan Society for the Promotion of Science JP 20K03650, JP 21J21512European Regional Development Fund PGC2018-093332-B-I0

Synthesis of Benzoisoselenazolones via Rh(III)-Catalyzed Direct Annulative Selenation by Using Elemental Selenium

Isoselenazolone derivatives have attracted significant research interest because of their potent therapeutic activities and indispensable applications in organic synthesis. Efficient construction of functionalized isoselenazolone scaffolds is still challenging, and thus new synthetic approaches with improved operational simplicity have been of particular interest. In this manuscript, we introduce a rhodium-catalyzed direct selenium annulation by using stable and tractable elemental selenium. A series of benzamides as well as acrylamides were successfully coupled with selenium under mild reaction conditions, and the obtained isoselenazolones could be pivotal synthetic precursors for several organoselenium compounds. Based on the designed control experiments and X-ray absorption spectroscopy measurements, we propose an unprecedented selenation mechanism involving a highly electrophilic Se(IV) species as the reactive selenium donor. The reaction mechanism was further verified by a computational study.This is the accepted version of the following article: Xu-Xu Q.F., Nishii Y., Uetake Y., et al. Synthesis of Benzoisoselenazolones via Rh(III)-Catalyzed Direct Annulative Selenation by Using Elemental Selenium. Chemistry - A European Journal 27, 17952 (2021); which has been published in final form at https://doi.org/10.1002/chem.202103485. This article may be used for non-commercialpurposes in accordance with the Wiley Self-ArchivingPolicy [https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html