Handling Molecular AggregationInduced Engine performance simply by Governed Polymerization

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Activation of dinitrogen (N2 , 78 %) and dioxygen (O2 , 21 %) has fascinated chemists and biochemists for decades. The industrial conversion of N2 into ammonia requires extremely high temperatures and pressures. Herein we report the first example of N2 and O2 cleavage by a uranium complex, [N(CH2 CH2 NPi Pr2 )3 U]2 (TMEDA), under ambient conditions without an external reducing agent. The N2 triple bond breaking implies a UIII -PIII six-electron reduction. The hydrolysis of the N2 reduction product allows the formation of ammonia or nitrogen-containing organic compounds. The interaction between UIII and PIII in this molecule allows an eight-electron reduction of two O2 molecules. This study establishes that the combination of uranium and a low-valent nonmetal is a promising strategy to achieve a full N2 and O2 cleavage under ambient conditions, which may aid the design of new systems for small molecules activation.
At Steno Diabetes Center Copenhagen (SDCC), diabetic retinopathy (DR) screening intervals are based on quantification of retinal lesions. Screening intervals are, for the milder forms of DR, prolonged to 2-3years. The purpose of the present study was to evaluate the effect of the prolongation on developing unexpected events and to evaluate the effect of HbA
and arterial hypertension.
We assessed 18972 screening intervals from 6000 patients from 1/1-2003 to 1/5-2017 for occurrence of unexpected events, defined as (1) DR progression requiring treatment, at the following screening date, and (2) DR-related hospital contact within the planned interval. We modelled the effect of several risk factors for developing unexpected events in a Cox regression. Furthermore, we assessed the risk of unexpected events in a logistic regression analysis using cubic splines to model the effect of HbA
, stratified by arterial hypertension status.
16283 (86%) intervals followed the planned interval and among those, only 86 (0.5%) experienced unexpected events. Intervals of dysregulated patients (86% of all intervals) did not experience more unexpected events, compared with well-regulated patient intervals (Hazard Ratio 1.12, 95% CI 0.55-2.27). We found a nonlinear effect of HbA
on the risk of unexpected events which peaked around HbA
levels of 80mmol/mol. Having arterial hypertension slightly increased the risk of unexpected events.
The present study supports the validity of the current algorithm. We found no increased risk of unexpected events among dysregulated intervals but a nonlinear effect of HbA
. Age, diabetes duration and diabetes type were significantly associated with unexpected events.
The present study supports the validity of the current algorithm. We found no increased risk of unexpected events among dysregulated intervals but a nonlinear effect of HbA1c . Age, diabetes duration and diabetes type were significantly associated with unexpected events.Environmentally friendly ZnSe/ZnS core/shell quantum dots (QDs) as an alternative blue emission material to Cd-based QDs have shown great potential for use in next-generation displays. However, it remains still challenging to realize a high-efficiency quantum dot light-emitting diode (QLED) based on ZnSe/ZnS QDs due to their insufficient electrical characteristics, such as excessively high electron mobility (compared to the hole mobility) and the deep-lying valence band. In this work, the effects of QDs doped with hole transport materials (hybrid QDs) on the electrical characteristics of a QLED are investigated. These hybrid QDs show a p-type doping effect, which leads to a change in the density of the carriers. Specifically, the hybrid QDs can balance electrons and holes by suppressing the overflow of electrons and improving injection of holes, respectively. These electrical characteristics help to improve device performance. In detail, an external quantum efficiency (EQE) of 6.88% is achieved with the hybrid QDs. This is increased by 180% compared to a device with pure ZnSe/ZnS QDs (EQE of 2.46%). This record is the highest among deep-blue Cd-free QLED devices. These findings provide the importance of p-type doping effect in QD layers and guidance for the study of the electrical properties of QDs.There is a growing interest in the research of natural products with potent activity in the prevention and treatment of diseases. Thereby, essential oil phytochemicals have demonstrated broad bioactivities. This study highlights the chemical composition of essential oils obtained from the leaves and inflorescences of diverse species of the genus Solidago (Solidago canadensis, Solidago gigantea, Solidago virgaurea and Solidago×niederederi), also known as Goldenrod, through GC/MS analysis, and their antiproliferative activity on three human tumor cell lines (MDA-MB 231, A375 and HCT116) by the MTT assay. The most represented chemical classes in the essential oils were oxygenated sesquiterpenes, sesquiterpene hydrocarbons, oxygenated monoterpenes and monoterpene hydrocarbons, with a remarkable contribution of compounds such as germacrene D (3.89-19.51 %), α-pinene (3.59-18.82 %), bornyl acetate (3.30-12.73 %) and caryophyllene oxide (3.07-9.18 %). Chemical quali- and quantitative differences were noticed between the leaves and flowers of the same species, as well as between the studied species. The MTT assay showed that the essential oils from the leaves were more active than those from the flower ones. learn more The essential oil having the highest impact on cell viability was that from S.×niederederi (IC50 =12.93, 6.72, and 6.82 μg/ml), followed by S. virgaurea (IC50 =13.39, 7.96, and 8.36 μg/ml) and finally S. gigantea (IC50 =18.04, 5.94, and 8.10 μg/ml) on MDA-MB 231, A375 and HCT116 cell lines, respectively. The essential oil from S. canadensis showed the lowest activity (IC50 =29.33, 12.63, and 18.03 μg/ml, respectively). Taken together, these findings highlight the Solidago species as good sources of cytotoxic compounds. Further studies are encouraged on the in vivo effects and safety of these products.
This study compares procedural and late clinical outcomes of left atrial appendage closure (LAAC) with Amplatzer devices as a single versus a combined procedure with other structural or coronary interventions.
Multiple cardiac conditions are frequent among elderly patients and invite simultaneous treatment to ensure a favorable patient outcomes.
559 consecutive patients (73.3 ± 11.1 years) underwent LAAC with Amplatzer devices at two centres (Bern and Zurich university hospitals, Switzerland) either as a single procedure or combined with other interventions. The primary safety endpoint was a composite of major peri-procedural complications and major bleeding at follow-up, the primary efficacy endpoint included stroke, systemic embolism, and cardiovascular/unexplained death. All event rates are reported per 100 patient-years.
In 263 single and 296 combined procedures with percutaneous coronary interventions (47.6%), closure of an atrial septal defect (8.4%) or a patent foramen ovale (36.5%), transcatheter aortic valve implantation (10.