Evidence and mechanism of efficient thermally activated delayed fluorescence promoted by delocalized excited states

The design of organic compounds with nearly no gap between the first excited singlet (S1) and triplet (T1) states has been demonstrated to result in an efficient spin-flip transition from the T1 to S1 state, that is, reverse intersystem crossing (RISC), and facilitate light emission as thermally activated delayed fluorescence (TADF). However, many TADF molecules have shown that a relatively appreciable energy difference between the S1 and T1 states (~0.2 eV) could also result in a high RISC rate. We revealed from a comprehensive study of optical properties of TADF molecules that the formation of delocalized states is the key to efficient RISC and identified a chemical template for these materials. In addition, simple structural confinement further enhances RISC by suppressing structural relaxation in the triplet states. Our findings aid in designing advanced organic molecules with a high rate of RISC and, thus, achieving the maximum theoretical electroluminescence efficiency in organic light-emitting diodes

The Efficacy of a Bilateral Approach for Treating Lesions With Chronic Total Occlusions The CART (Controlled Antegrade and Retrograde subintimal Tracking) Registry

ObjectivesThe aim of this study was to evaluate the safety and feasibility of a new concept for chronic total occlusion (CTO) recanalization—using a bilateral approach that utilizes a Controlled Antegrade and Retrograde subintimal Tracking (CART) technique.BackgroundSuccessful percutaneous recanalization of coronary CTOs results in improved long-term outcomes. The recanalization of CTOs in native coronary arteries no doubt represents one of the most technically challenging of interventional procedures.MethodsA total of 224 consecutive patients (mean age 61 ± 9 years; 86.2% men) were enrolled in this prospective multicenter registry. This technique combines the simultaneous use of antegrade and retrograde approaches. A subintimal dissection is created in both antegrade and retrograde fashion, thereby limiting the extension of the subintimal dissection within the CTO portion.ResultsOf 224 CTO lesions (>3 months in duration) undergoing attempted recanalization using the CART technique, 145 cases (64.7%) had undergone previous CTO recanalization attempts. The success rates of crossing in a retrograde fashion with a wire and a balloon were 87.9% and 79.9%, respectively. The overall technical and procedural success rates achieved in this registry were 92.4% and 90.6%, respectively.ConclusionsA bilateral approach for CTO lesions using the CART technique is feasible, safe, and has a higher success rate than previous approaches. These results indicate that a bilateral technique can solve a major dilemma that commonly affects CTO procedures

ラット静脈管の発生分化

We used scanning electron microscopy to observe the development of the ductus venosus in the fetal rat liver. At day 13 of gestation, the vascular system in the liver was already formed and the umbilical vein had branched many capillaries to the parenchyma of the liver and was connected to the posterior vena cava directly by one small ductus venosus. At day 14 of gestation, the umbilical vein bulged at its terminal part and bifurcated into the ductus venosus, which joined the posterior vena cava, and a branch that anastomosed with the vitelline vein. The ductus venosus had no branches and subsequently enlarged and then degenerated just before birth. The bulging part of the umbilical vein and its branches degenerated in the later stages of gestation. The vitelline vein developed to form the capillaries of the liver and the intestinal venous system. In the SD rat liver, the ductus venosus was therefore established by development of the terminal part of the umbilical vein, which anastomosed directly with the posterior vena cava.ラットの肝臓内静脈管の発生分化を走査型電子顕微鏡で観察を行った.胎齢13日では肝臓内毛細血管はすでに形成されており,月齊静脈は肝臓実質内に毛細血管を分枝し,細い静脈管を介して後大静脈に合流していた.胎齢14日では,膀静脈終末部は膨大し,この膨大部は二分岐し,1本は後大静脈に連絡する静脈管で,他の枝は卵黄嚢静脈に連絡する吻合枝であった.静脈管は胎齢20日頃までは成長し,分娩直前になると退化を始めていた,また,静脈管から分枝する毛細血管は認められなかった.膀静脈終末部の膨大部は胎齢後期になると退化していた.卵黄嚢静脈は腸管の静脈を形成し,肝臓内では多くの毛細血管に分枝していた.ラットの肝臓では,後大静脈に直接吻合する1本の膀静脈終末部から静脈管が分化すると考えられる