Synthesis of 1-(pyridyl, quinolyl, and isoquinolyl)azulenes by Reissert-Henze type reaction

Azulene derivatives reacted with N-oxide of several heterocycles in the presence of trifluoromethanesultonic anhydride (Tf(2)O) to afford 1-(pyridyl, quinolyl, and isoquinolyl)azulenes in good yield, respectively. In the case of the reaction with the 1-azulenyl methyl sulfide (12), 1,1'-biazulene derivative 13 was obtained under the similar reaction conditions. The first synthesis of unsymmetrical 1,3-di(pyridyl)azulene derivative was also established via our new preparation method following the electrophilic pyriclinylation using the reaction with pyridine in the presence of Tf(2)O.ArticleTETRAHEDRON LETTERS. 51(39):5127-5130 (2010)journal articl

Difference between 5A score and the HOPE score

Recently, a letter to the editor was published to comment on the 5A score which is the prediction model for accidental hypothermia patients comparing the HOPE score. In this letter, we responded to the comments to clarify the difference between the 5A score and the HOPE score

External validation of 5A score model for predicting in-hospital mortality among the accidental hypothermia patients: JAAM-Hypothermia study 2018–2019 secondary analysis

[Background] The 5A score including five components “Age, Activities of daily living, Arrest, Acidemia and Albumin” was developed as an easy-to-use screening tool for predicting in-hospital mortality among patients with accidental hypothermia. However, the external validity of the 5A score has not yet been evaluated. We aimed to perform an external validation of the 5A score model. [Method] This secondary analysis of the multicenter, prospective cohort Japanese Association for Acute Medicine-Hypothermia Study (2018–2019), which was conducted at 87 and 89 institutions throughout Japan, collected data from December 2018 to February 2019 and from December 2019 to February 2020. Adult accidental hypothermia patients whose body temperature was 35 °C or less were included in this analysis. The probability of in-hospital mortality was calculated using a logistic regression model of the 5A score. The albumin was not recorded in this database; thus, it was imputed by estimation. Predictions were compared with actual observations to evaluate the calibration of the model. Furthermore, decision-curve analysis was used to evaluate the clinical usefulness. [Results] Of the 1363 patients registered in the database, data of 1139 accidental hypothermia patients were included for analysis. The median [interquartile range] age was 79 [68–87] years, and there were 625 men (54.9%) in the study cohort. The predicted probability and actual observation by risk groups produced the following results: low 7% (5.4–8.6), mild 19.1% (17.4–20.8), moderate 33.2% (29.9–36.5), and high 61.9% (55.9–67.9) predicted risks, and the low 12.4% (60/483), mild 17.7% (59/334), moderate 32.6% (63/193), and high 69% (89/129) observed mortality. These results indicated that the model was well calibrated. Decision-curve analysis visually indicated the clinical utility of the 5A score model. [Conclusion] This study indicated that the 5A score model using estimated albumin value has external validity in a completely different dataset from that used for the 5A model development. The 5A score is potentially helpful to predict the mortality risk and may be one of the valuable information for discussing the treatment strategy with patients and their family members

Effect of field damping layer on two step absorption of quantum dots solar cells

Multi-stacked InAs/AlGaAs quantum dot solar cells (QDSCs) introduced with field damping layers (FDL) which sustain the junction built-in potential have been studied. Without an external bias condition, the external quantum efficiency (EQE) of QD layers are reduced by introducing the thick FDL, because the carrier escape due to built-in electric field was suppressed. On the other hand, the photocurrent production due to two-step absorption is increased by the formation of flat-band QD structure for QDSC with thick FDL

Neutron Activation Analysis of Thorium by the Use of the Japan Materials Testing Reactor

Hydraulic power rabbit in the Japan Materials Testing Reactor (JMTR) was used for highly sensitive neutron activation analysis of thorium in silica and aluminum. The thermal neutron flux of JMTR is higher than 1x10^n/cm^2/sec. A number of radioactive isotopes were made from impurities of high purity aluminum and silica irradiated in JMTR. ^Ta, which was produced from ^Ta by (2n, γ) reaction, was observed and made the determination of thorium difficult. The objective activation products ^Pa for the determination of thorium was isolated from majority of interfering radioactivity by a method combined with anion exchange and LaF_3 coprecipitation. It was found that the detection limit of thorium was less than 2x10^g. The method is useful to the analysis for thorium in high purity aluminum and silica that might be used to make very large scale integrated circuit