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Herein, we present a simple design concept for a monomer that affords individually separated supramolecular polymer chains.

A technique to monitor the permeation behavior of tritium in metals to pure water was successfully developed. A metal membrane separated two containers: one is for tritium loading as an upstream si...

Background: This study aimed to determine the safety and efficacy of sphenopalatine artery (SPA) surgery in patients with refractory epistaxis and to identify factors associated with the indications for surgery to assist clinicians in making prompt and appropriate decisions regarding SPA surgery for refractory epistaxis. Methods: We analyzed 97 consecutive patients with nasal bleeding hospitalized in our institution between April 2009 and March 2018. Clinicopathological characteristics and clinical outcomes were analyzed from retrospective chart reviews. Results: Of the 97 patients, 28 (29 sides) required SPA surgery. There were no differences in sex, anti-coagulant drug or antiplatelet use, hemoglobin concentration, or platelet count between Group A (patients who required surgery) and Group B (patients who did not require surgery). Age (58 vs. 67 years, p = 0.038) and severity of comorbidity (0 vs. 1, p = 0.039) were significantly lower in the surgery group. Patients who were younger and had lower Charlson Comorbidity Index (CCI) scores had more requirements for surgery than those who were older and had higher CCI scores. There was no significant difference between the groups with respect to the proportion of patients receiving blood transfusions; however, the length of hospitalization was significantly longer in Group A than in Group B (8.9 vs. 8 days, p = 0.038). Success rate (non-rebleeding rate) was 89%, comparable to that reported in previous studies. Conclusions: Endoscopic SPA surgery was found safe and effective method with few complications. Younger patients with lower CCI scores were found appropriate for SPA surgery for refractory epistaxis due in part to a lower risk of anesthesia.

As part of an ongoing study of near infrared (NIR) absorbing dyes applicable to optoelectronics, thieno[1,3,2]oxazaborinine-containing aza-BODIPYs were synthesized for the first time. 3,5-Di(thiophene)-substituted N2O2-type 1 showed a NIR absorption band centered at 780 nm, with a molar extinction coefficient (emax) of 5.51 × 104 M−1 cm−1 in CH2Cl2; however, it was easily hydrolyzed in solution. In comparison, 3-thiophene-containing N2O-type analogues 2 and 3 had greater stability, and NIR absorption bands at 768 nm (emax = 8.62 × 104 M−1 cm−1) and 779 nm (emax = 6.32 × 104 M−1 cm−1), respectively, in CH2Cl2. Notably, these dyes had longer absorption bands than those of all of the structurally constraining aza-BODIPYs reported thus far. CV measurements and theoretical calculations indicated that this shift was the result of a higher-lying HOMO energy level generated by incorporation of thiophene into the aza-BODIPY core. As a potential device application, the 3-loaded film was prepared on indium tin oxide (ITO). The film showed a NIR absorption band at 827 nm, with a wide spectral range, and a λonset value of 897 nm; thus, its applicability as a NIR photodetector was evaluated through fabrication of a single-component device. The ITO/3 (85 nm)/Al (100 nm) device produced a photocurrent of 9.57 × 10−7 A cm−2 at a bias potential of 1 V upon illumination at 850 nm and a fluence of 130 μW cm−2. This demonstrated the potential of thieno[1,3,2]oxazaborinine-containing aza-BODIPY materials in optoelectronic applications such as NIR photodetectors.

In this short review, we provide an overview of multistep molecular and macromolecular assembly in syntheses of higher-order structures that are unobtainable under thermodynamic control. As in the case of organic/macromolecular chemistry, a synthetic scheme is designed such that a series of assembly processes eventually leads to a complex structure. The recent progress in this research field has been made based on the mechanistic understandings from viewpoints of both thermodynamics and kinetics. We also describe relevant systems which make use of advanced experimental apparatuses such as optical tweezers, high-speed atomic force microscopy, and so on. The unprecedented structures obtainable in this way might play a pivotal role in bridging the hierarchical levels from the molecular scale to the macroscopic world, leading to new functional supramolecular materials.