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991.

Objectives

We sought to investigate angiographic indications for the use of the STENTYS technique and evaluated the long-term safety and clinical efficacy of the stent.

Background

Coronary lesions involving complex anatomy, including aneurysmatic, ectatic, or tapered vessel segments often carry a substantial risk of stent malapposition. The self-apposing stent technique may reduce the risk of stent malapposition and therefore improve clinical outcomes.

Methods

A total of 120 consecutive patients treated with the STENTYS stent were included (drug-eluting stent (DES) n?=?101, bare-metal stent (BMS) n?=?19). All lesions were scored for angiographic indications for the STENTYS stent, including aneurysms, ectasias, tapering, absolute diameters, bifurcation lesions, and saphenous vein grafts. Off-line quantitative coronary angiography analyses were performed pre-procedure and post-procedure. Five years follow-up was obtained including cardiac death, target vessel myocardial infarction (TV-MI), target vessel revascularisation, stent thrombosis, and the composite endpoint target vessel failure (cardiac death, TV-MI and target vessel revascularisation).

Results

Angiographic indications for STENTYS use were aneurysm (30%), ectasia (19%), tapering (27%), bifurcation lesions (8%), and saphenous vein graft lesions (16%) and absolute diameters (22%). Mean maximal diameter was 4.51?±?0.99?mm. At 5?year follow-up target vessel failure rates were 24.1% in the total cohort (DES 22.8% vs. BMS 33%, p?=?0.26). Definite stent thrombosis rate was 3.8% at 5?year follow-up in this cohort with complex and high-risk lesions (DES 4.5% vs. BMS 0%, p?=?0.39).

Conclusions

Angiographic indications for the use of the self-apposing stent were complex lesions with atypical coronary anatomy. Our data showed reasonable stent thrombosis rates at 5?year follow-up, considering the high-risk lesion characteristics.
  相似文献   
992.
Solution‐processed colloidal quantum dot (CQD) solar cells harvesting the infrared part of the solar spectrum are especially interesting for future use in semitransparent windows or multilayer solar cells. To improve the device power conversion efficiency (PCE) and stability of the solar cells, surface passivation of the quantum dots is vital in the research of CQD solar cells. Herein, inorganic CsPbI3 perovskite (CsPbI3‐P) coating on PbS CQDs with a low‐temperature, solution‐processed approach is reported. The PbS CQD solar cell with CsPbI3‐P coating gives a high PCE of 10.5% and exhibits remarkable stability both under long‐term constant illumination and storage under ambient conditions. Detailed characterization and analysis reveal improved passivation of the PbS CQDs with the CsPbI3‐P coating, and the results suggest that the lattice coherence between CsPbI3‐P and PbS results in epitaxial induced growth of the CsPbI3‐P coating. The improved passivation significantly diminishes the sub‐bandgap trap‐state assisted recombination, leading to improved charge collection and therefore higher photovoltaic performance. This work therefore provides important insight to improve the CQD passivation by coating with an inorganic perovskite ligand for photovoltaics or other optoelectronic applications.  相似文献   
993.
Bier  Peter V.  Persche  Malachi  Koch  Paul  Soldat  Douglas J. 《Plant and Soil》2018,432(1-2):303-314

Aims

Buckwheat (Fagopyrum esculentum) is highly tolerant to Al stress, but the molecular mechanisms remain largely unknown. This study aims to investigate a half-type ABC transporter gene (FeSTAR1) with respect to Al tolerance.

Methods

The expression of FeSTAR1 was examined and complementation test in atstar1 mutant was conducted. Furthermore, Al distribution and cell wall polysaccharides content were analyzed.

Results

FeSTAR1 is an ABC transporter protein with nucleotide binding domain, but lack of transmembrane domain. Consistently, FeSTAR1 is a soluble protein, localizing to both cytoplasm and nucleus. Al rapidly and specifically induced FeSTAR1 expression. Heterologous expression of FeSTAR1 in atstar1 rescued its Al tolerance, and exogenous applied UDP-glucose could alleviate Al sensitivity of atstar1 mutant, suggesting the connection between FeSTAR1 and UDP-glucose in terms of Al tolerance. Furthermore, FeSTAR1 complemented lines accumulated less Al in root cell wall than atstar1 mutant. Further cell wall fraction analysis showed that Al was largely confined to cell wall hemicellulose1, at which Al content was significantly lower in complemented lines. Consistent with Al distribution in different cell wall polysaccharides, complemented lines had lower hemicellulose1 content.

Conclusion

Our results indicate that FeSTAR1 is involved in Al resistance via possibly cell wall matrix polysaccharides metabolism in buckwheat.
  相似文献   
994.
995.
The distinctive braconine wasp genus Rhytimorpha Szépligeti is distributed through Africa and the Near East. We provide photographic illustrations of the type specimens of the two species of Rhytimorpha known up to the present, R. coccinea Szépligeti and R. nigriceps Szépligeti. Previous published records of R. coccinea from Israel by J. Papp are confirmed. A new species, R. pappi Quicke & Butcher sp. n. is described based on a female from Holot Agur, a semi-desert area in the Negev Dunes in northeastern Sinai Peninsula.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:B5CDA65C-5341-4A61-9C85-2A7A70D7D4C1  相似文献   

996.
Increased global demands for food have raised interest for seaweed as a healthy and sustainable food source. At the same time, the large amounts of microplastic in the oceans have raised concern in relation to pollution of seafood including sea vegetables. The aim of this study was to examine sorption of fluorescent polystyrene (PS) microplastic particles to edible macroalga (seaweed) Fucus vesiculosus, and to investigate to what extent adsorbed PS particles could be washed off, using an industrial relevant method. PS microplastic particles (diameter of 20 μm) were used in a concentration of 2.65 mg L?1 (corresponding to 597 particles per mL) in filtrated seawater (50 mL) to treat F. vesiculosus distal tips in blue cap flasks (100 mL) placed in a rotary box for 2 h. Results showed sorption of PS microplastic particles to F. vesiculosus analysed by microscopy and a significant reduction of 94.5% by washing. These results were based on high microplastic concentrations, not comparable to natural conditions/concentrations. Nonetheless, this study provides methodological and mechanistic insights into procedures for investigating the sorption of microplastics to seaweed, for which there is currently no established standardised method.  相似文献   
997.
Identifying factors influencing nest survival among sympatric species is important for understanding and managing sources of variation in population dynamics of individual species. Three species of loons nest sympatrically in northern Alaska and differ in body size, life history characteristics, and population trends. We tested the effects of competition, nest site selection, and water level variations on nest survival of Pacific Gavia pacifica, yellow‐billed G. adamsii, and red‐throated loons G. stellata on the Arctic Coastal Plain in Alaska. Although overall nest survival rates did not differ between species, the factors influencing nest survival varied. Nest site selection influenced nest survival for Pacific and yellow‐billed loons, with both species having high nest survival when nesting on islands and peninsulas, likely due to a reduction in access by terrestrial predators. However, on mainland shorelines, Pacific loons had lower nest survival than yellow‐billed loons, and used a higher proportion of vegetation mats for nest sites suggesting that their smaller body size makes them less adept at nest defense. Nest site selection did not influence nest survival of red‐throated loons corresponding to our result of no nest site preferences by this species. Initiation date had a strong influence on nest survival for Pacific and yellow‐billed loons with nests laid earlier having higher survival. Pacific and yellow‐billed loon nests were susceptible to flooding due to precipitation, which contrasted with red‐throated loons that nest on smaller lakes with lower water level variations. Competition did not affect nest survival for any of the species likely due to most territorial encounters occurring prior to incubation. The only influence we found on red‐throated loon nest survival was differences among years. Our results indicate that loons chose nest sites based on predation risk and that factors influencing breeding success of closely related species may differ under similar breeding conditions.  相似文献   
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