Full observation of ultrafast cascaded radiationless transitions from S2(ππ-) state of pyrazine using vacuum ultraviolet photoelectron imaging

A photoexcited molecule undergoes multiple deactivation and reaction processes simultaneously or sequentially, which have been observed by combinations of various experimental methods. However, a single experimental method that enables complete observation of the photo-induced dynamics would be of great assistance for such studies. Here we report a full observation of cascaded electronic dephasing from S2(ππ∗) in pyrazine (C4N2H4) by time-resolved photoelectron imaging (TRPEI) using 9.3-eV vacuum ultraviolet pulses with a sub-20 fs time duration. While we previously demonstrated a real-time observation of the ultrafast S2(ππ∗) → S1(nπ∗) internal conversion in pyrazine using TRPEI with UV pulses, this study presents a complete observation of the dynamics including radiationless transitions from S1 to S0 (internal conversion) and T1(nπ∗) (intersystem crossing). Also discussed are the role of 1Au(nπ∗) in the internal conversion and the configuration interaction of the S2(ππ∗) electronic wave function

Quasi-Periodic Growth of One-Dimensional Copper Boride on Cu(110)

An unexplored material of copper boride has been realized recently in two-dimensional form at a (111) surface of the fcc copper crystal. Here, one-dimensional (1-D) boron growth was observed on the Cu(110) surface, as probed by atomically resolved scanning probe microscopy. The 1-D copper boride was composed of quasi-periodic atomic chains periodically aligned parallel to each other, as confirmed by Fourier transform analysis. The 1-D growth unexpectedly proceeded across surface steps in a self-assembled manner and extended over several 100 nm. The long-range formation of a 1-D quasi-periodic structure on a surface has been theoretically modeled as a 1-D quasi-crystal and the predicted conditions matched the structural parameters obtained by the experimental work here. The quasi-periodic 1-D copper boride system enabled a way to examine 1-D quasi-crystallinity on an actual material

Treatment strategy changes for inflammatory bowel diseases in biologic era: results from a multicenter cohort in Japan, Far East 1000

Abstract Many molecular targeted agents, including biologics, have emerged for inflammatory bowel diseases (IBD), but their high prices have prevented their widespread use. This study aimed to reveal the changes in patient characteristics and the therapeutic strategies of IBD before and after the implementation of biologics in Japan, where the unique health insurance system allows patients with IBD and physicians to select drugs with minimum patient expenses. The analysis was performed using a prospective cohort, including IBD expert and nonexpert hospitals in Japan. In this study, patients were classified into two groups according to the year of diagnosis based on infliximab implementation as the prebiologic and biologic era groups. The characteristics of therapeutic strategies in both groups were evaluated using association analysis. This study analyzed 542 ulcerative colitis (UC) and 186 Crohn’s disease (CD). The biologic era included 53.3% of patients with UC and 76.2% with CD, respectively. The age of UC (33.9 years vs. 38.8 years, P < 0.001) or CD diagnosis (24.3 years vs. 31.9 years, P < 0.001) was significantly higher in the biologic era group. The association analysis of patients with multiple drug usage histories revealed that patients in the prebiologic era group selected anti-tumor necrosis factor (TNF)-α agents, whereas those in the biologic era group preferred biologic agents with different mechanisms other than anti-TNF-α. In conclusion, this study demonstrated that both patient characteristics and treatment preferences in IBD have changed before and after biologic implementation