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991.
Yong Hyun Kim Jonghee Lee Simone Hofmann Malte C. Gather Lars Müller‐Meskamp Karl Leo 《Advanced functional materials》2013,23(30):3763-3769
Efficient transparent organic light‐emitting diodes (OLEDs) with improved stability based on conductive, transparent poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) electrodes are reported. Based on optical simulations, the device structures are carefully optimized by tuning the thickness of doped transport layers and electrodes. As a result, the performance of PEDOT:PSS‐based OLEDs reaches that of indium tin oxide (ITO)‐based reference devices. The efficiency and the long‐term stability of PEDOT:PSS‐based OLEDs are significantly improved. The structure engineering demonstrated in this study greatly enhances the overall performances of ITO‐free transparent OLEDs in terms of efficiency, lifetime, and transmittance. These results indicate that PEDOT:PSS‐based OLEDs have a promising future for practical applications in low‐cost and flexible device manufacturing. 相似文献
992.
Flávia Emi Razera Baldasso Caroline Patta Stürmer Simone Bonato Luisi Maria Noel Marzano Rodrigues Petruzzi Roberta Kochenborger SCARPARO José Antônio Poli De Figueiredo 《Microscopy research and technique》2012,75(11):1557-1563
The aim of the present study was to characterize, by means of SEM, primary endodontic infections and to correlate with clinical and radiographic findings. Twelve (12) human extracted teeth (19 roots) presenting primary endodontic infection were examined. SEM qualitative observations of bacterial and defense cells, their features and distribution within the root canal lumen and root dentine were recorded for association with clinical and radiographic tabled data. Although a direct correlation between biofilm composition and clinical/radiographic findings was not established, structural organization and distribution of the biofilm, as well as the characteristics of host response, could be easily related to those features. Bacterial biofilm was predominant at the apical third. Symptomatic apical periodontitis was related to presence of bacterial biofilm all thirds. Defense cells could be seen in the apical third of some samples. These cells were present in all thirds in some of the cases with open cavities. The correlations performed in this study allowed a better understanding of the picture of primary endodontic infection, host response and relevant clinical features. The combined use of scanning electron microscopy with clinical and radiographic evaluation has the potential to overcome some limits of the current knowledge related to pulpal and periapical diseases, providing important insights for improving treatment strategies. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc. 相似文献
993.
Detection of Traces of Ovalbumin and Casein in White and Red Wines by Quantitative Western Blotting 下载免费PDF全文
Fining of wine with agents containing cow's milk or hen's egg white is a common and traditional procedure. In light of increasing food allergies all over the world, the presence of fining residues has been subject of intense debate. Switzerland does not make exception, and since 2009 the Federal Department of Home Affairs has modified its food regulations stating that the labels must show if traces of fining agents are present. Nevertheless, the application of this regulation is not based on an official analytical method. In this study we show that immunoblotting is an efficient technique to detect and quantify ovalbumin and casein residues in bottled wine. We showed that final filtration is an essential step to remove finings in red wine, and that overfining of white wine may result in fining residues in finished products. Finally, for the first time in Switzerland, 22 samples were taken by food safety inspectors and officially analyzed for the regional food control authority of the Canton of Vaud. These samples were allergen free, but a larger study is currently planned in collaboration with other regional authorities of Switzerland to complete these results and make a complete picture of the Swiss wine production. 相似文献
994.
995.
In this work we present a mixed-integer model for the optimal design of production/transportation systems. In contrast to
standard design problems, our model is originally based on a coupled system of differential equations capturing the dynamics
of manufacturing processes and stocks. The problem is to select an optimal parameter configuration from a predefined set such
that respective constraints are fulfilled. We focus on single commodity flows over large time scales as well as highly interconnected
networks and propose a suitable start heuristic to ensure feasibility and to speed up the solution procedure. 相似文献
996.
Brezesinski K Haetge J Wang J Mascotto S Reitz C Rein A Tolbert SH Perlich J Dunn B Brezesinski T 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(3):407-414
Herein is reported the synthesis of ordered mesoporous α-Fe(2)O(3) thin films produced through coassembly strategies using a poly(ethylene-co-butylene)-block-poly(ethylene oxide) diblock copolymer as the structure-directing agent and hydrated ferric nitrate as the molecular precursor. The sol-gel derived α-Fe(2)O(3) materials are highly crystalline after removal of the organic template and the nanoscale porosity can be retained up to annealing temperatures of 600 °C. While this paper focuses on the characterization of these materials using various state-of-the-art techniques, including grazing-incidence small-angle X-ray scattering, time-of-flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy, and UV-vis and Raman spectroscopy, the electrochemical properties are also examined and it is demonstrated that mesoporous α-Fe(2)O(3) thin-film electrodes not only exhibit enhanced lithium-ion storage capabilities compared to bulk materials but also show excellent cycling stabilities by suppressing the irreversible phase transformations that are observed in microcrystalline α-Fe(2)O(3). 相似文献
997.
Peletto S Bertuzzi S Campanella C Modesto P Maniaci MG Bellino C Ariello D Quasso A Caramelli M Acutis PL 《International journal of molecular sciences》2011,12(11):7732-7747
The use of reference genes is commonly accepted as the most reliable approach to normalize qRT-PCR and to reduce possible errors in the quantification of gene expression. The most suitable reference genes in sheep have been identified for a restricted range of tissues, but no specific data on whole blood are available. The aim of this study was to identify a set of reference genes for normalizing qRT-PCR from ovine whole blood. We designed 11 PCR assays for commonly employed reference genes belonging to various functional classes and then determined their expression stability in whole blood samples from control and disease-stressed sheep. SDHA and YWHAZ were considered the most suitable internal controls as they were stably expressed regardless of disease status according to both geNorm and NormFinder software; furthermore, geNorm indicated SDHA/HPRT, YWHAZ/GAPDH and SDHA/YWHAZ as the best reference gene combinations in control, disease-stressed and combined sheep groups, respectively. Our study provides a validated panel of optimal control genes which may be useful for the identification of genes differentially expressed by qRT-PCR in a readily accessible tissue, with potential for discovering new physiological and disease markers and as a tool to improve production traits (e.g., by identifying expression Quantitative Trait Loci). An additional outcome of the study is a set of intron-spanning primer sequences suitable for gene expression experiments employing SYBR Green chemistry on other ovine tissues and cells. 相似文献
998.
Segawa TF Bornet A Salvi N Miéville P Vitzthum V Carnevale D Jannin S Caporini MA Ulzega S Vasos PR Rey M Bodenhausen G 《Chimia》2011,65(9):652-655
Among the different fields of research in nuclear magnetic resonance (NMR) which are currently investigated in the Laboratory of Biomolecular Magnetic Resonance (LRMB), two subjects that are closely related to each other are presented in this article. On the one hand, we show how to populate long-lived states (LLS) that have long lifetimes T(LLS) which allow one to go beyond the usual limits imposed by the longitudinal relaxation time T1. This makes it possible to extend NMR experiments to longer time-scales. As an application, we demonstrate the extension of the timescale of diffusion measurements by NMR spectroscopy. On the other hand, we review our work on long-lived coherences (LLC), a particular type of coherence between two spin states that oscillates with the frequency of the scalar coupling constant J(IS) and decays with a time constant T(LLC). Again, this time constant T(LLC) can be much longer than the transverse relaxation time T2. By extending the coherence lifetimes, we can narrow the linewidths to an unprecedented extent. J-couplings and residual dipolar couplings (RDCs) in weakly-oriented phases can be measured with the highest precision. 相似文献
999.
Guarino C Arena S De Simone L D'Ambrosio C Santoro S Rocco M Scaloni A Marra M 《Molecular nutrition & food research》2007,51(2):255-262
Apple is one of the most worldwide-consumed fruits and a number of cultivars, differing in organoleptic and nutritional characteristics, are available for the market. Annurca apple is a regional variety from Southern Italy, which is known for crispness, excellent taste and long shelf life of fruits. These features have renewed the interest in the investigation of their genetic potential and different studies have lead to their partial genetic and metabolic characterisation. In this study, we present the analysis of the protein repertoire of the pseudocarp tissues of three accessions of Malus x domestica Borkh. cv. Annurca, as first example of the systematic annotation of the apple proteome. Proteins were extracted from fruit tissues and resolved on 2-DE gels; commonly expressed proteins were in-gel digested and analysed by MALDI-TOF-MS and muLC-ESI-IT-MS/MS approaches. Peptide MS and MS/MS data were searched against publicly available protein and EST databases, and 44 spots were identified and associated to 28 different species. They were related to important physiological processes such as energy production, ripening and stress response. The occurrence of allergens causative of widespread food allergy syndromes was also detected. Integration of genomic, metabolomic and proteomic data will be indispensable for future molecular characterisation and hence full exploitation of the peculiar organoleptic, nutritional and agronomic traits of local cultivars of fruits. 相似文献
1000.
Paula Andrea Osorio Carmona Lorena Costa Garcia José Antônio de Aquino Ribeiro Leonardo Fonseca Valadares Adriano de Figueiredo Marçal Luiz Ferreira de França Simone Mendonça 《Food and Bioprocess Technology》2018,11(9):1703-1718
Carotenoids were extracted from pressed palm fiber using supercritical CO2 and microencapsulated by spray-drying with gum Arabic. Twenty-eight tests were made. Emulsions were characterized with respect to droplet size and viscosity. The effects of solid content and spray-drying conditions on moisture, hygroscopicity, microencapsulation efficiency, and powder lipid oxidation were investigated. Particles produced at optimized process (35% of solids, feed flow of 26%, temperature of 166 °C, and atomization air flow of 40 mm) were evaluated for major carotenoids identification and fatty acid profile. Higher solid content led to higher encapsulation efficiency and lower lipid oxidation, which was related to the higher emulsion viscosity and lower droplet size. Increasing atomization air flow and temperature resulted in higher lipid oxidation. Moisture increased and higroscopicity decreased when higher feed flow and lower temperature were used. Microparticles presented high content of monounsaturated fatty acids, α-, β-, and (9Z)-β-carotene and reflected the composition of un-encapsulated oil. 相似文献