Bright Blue Solution Processed Triple‐Layer Polymer Light‐Emitting Diodes Realized by Thermal Layer Stabilization and Orthogonal Solvents

The realization of fully solution processed multilayer polymer light‐emitting diodes (PLEDs) constitutes the pivotal point to push PLED technology to its full potential. Herein, a fully solution processed triple‐layer PLED realized by combining two different deposition strategies is presented. The approach allows a successive deposition of more than two polymeric layers without extensively redissolving already present layers. For that purpose, a poly(9,9‐dioctyl‐fluorene‐co‐N‐(4‐butylphenyl)‐diphenylamine) (TFB) layer is stabilized by a hard‐bake process as hole transport layer on top of poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). As emitting layer, a deep blue emitting pyrene‐triphenylamine copolymer is deposited from toluene solution. To complete the device assembly 9,9‐bis(3‐(5′,6′‐bis(4‐(polyethylene glycol)phenyl)‐[1,1′:4′,1″‐terphenyl]‐2′‐yl)propyl)‐9′,9′‐dioctyl‐2,7‐polyfluorene (PEGPF), a novel polyfluorene‐type polymer with polar sidechains, which acts as the electron transport layer, is deposited from methanol in an orthogonal solvent approach. Atomic force microscopy verifies that all deposited layers stay perfectly intact with respect to morphology and layer thickness upon multiple solvent treatments. Photoelectron spectroscopy reveals that the offsets of the respective frontier energy levels at the individual polymer interfaces lead to a charge carrier confinement in the emitting layer, thus enhancing the exciton formation probability in the device stack. The solution processed PLED‐stack exhibits bright blue light emission with a maximum luminance of 16 540 cd m^?2 and a maximum device efficiency of 1.42 cd A^?1, which denotes a five‐fold increase compared to corresponding single‐layer devices and demonstrates the potential of the presented concept.     

Controlling the Functional Properties of Oligothiophene Crystalline Nano/Microfibers via Tailoring of the Self‐Assembling Molecular Precursors

Oligothiophenes are π‐conjugated semiconducting and fluorescent molecules whose self‐assembly properties are widely investigated for application in organic electronics, optoelectronics, biophotonics, and sensing. Here an approach to the preparation of crystalline oligothiophene nano/microfibers is reported based on the use of a “sulfur overrich” quaterthiophene building block, ? T4S4 ? , containing in its covalent network all the information needed to promote the directional, π–π stacking‐driven, self‐assembly of Y‐T4S4‐Y oligomers into fibers with hierarchical supramolecular arrangement from nano‐ to microscale. It is shown that when Y varies from unsubstituted thiophene to thiophene substituted with electron‐withdrawing groups, a wide redistribution of the molecular electronic charge takes place without substantially affecting the aggregation modalities of the oligomer. In this way, a structurally comparable series of fibers is obtained having progressively varying optical properties, redox potentials, photoconductivity, and type of prevailing charge carriers (from p‐ to n‐type). With the aid of density functional theory (DFT) calculations, combined with powder X‐ray diffraction data, a model accounting for the growth of the fibers from molecular to nano‐ and microscale is proposed.     

Amniotic Fluid Embolism Pathophysiology Suggests the New Diagnostic Armamentarium: β-Tryptase and Complement Fractions C3-C4 Are the Indispensable Working Tools

Amniotic fluid embolism (AFE) is an uncommon obstetric condition involving pregnant women during labor or in the initial stages after delivery. Its incidence is estimated to be around 5.5 cases per 100,000 deliveries. Therefore, this paper investigated the pathophysiological mechanism, which underlies AFE, in order to evaluate the role of immune response in the development of this still enigmatic clinical entity. The following databases (from 1956 to September 2014) Medline, Cochrane Central, Scopus, Web of Science and Science Direct were used, searching the following key words: AFE, pathophysiology, immune/inflammatory response, complement and anaphylaxis. The main key word “AFE” was searched singularly and associated individually to each of the other keywords. Of the 146 sources found, only 19 were considered appropriate for the purpose of this paper. The clinical course is characterized by a rapid onset of symptoms, which include: acute hypotension and/or cardiac arrest, acute hypoxia (with dyspnoea, cyanosis and/or respiratory arrest), coagulopathies (disseminated intravascular coagulation and/or severe hemorrhage), coma and seizures. The pathology still determines a significant morbidity and mortality and potential permanent neurological sequelae for surviving patients. At this moment, numerous aspects involving the pathophysiology and clinical development are still not understood and several hypotheses have been formulated, in particular the possible role of anaphylaxis and complement. Moreover, the detection of serum tryptase and complement components and the evaluation of fetal antigens can explain several aspects of immune response.     

Receptor-mediated internalization of insulin. Potential role of pp120/HA4, a substrate of the insulin receptor kinase

pp120/HA4 is a hepatocyte membrane glycoprotein phosphorylated by the insulin receptor tyrosine kinase. In this study, we have investigated the role of pp120/HA4 in insulin action. Transfection of antisense pp120/HA4 cDNA in H35 hepatoma cells resulted in inhibition of pp120/HA4 expression and was associated with a 2-3-fold decrease in the rate of insulin internalization. Furthermore, insulin internalization in NIH 3T3 fibroblasts co-transfected with insulin receptors and pp120/HA4 was increased 2-fold compared with cells expressing insulin receptors alone. In contrast, no effect on internalization was observed in cells overexpressing a naturally occurring splice variant of pp120/HA4 that lacks the phosphorylation sites in the intracellular domain. Insulin internalization was also unaffected in cells expressing three site-directed mutants of pp120/HA4 in which the sites of phosphorylation by the insulin receptor kinase had been removed (Y488F, Y488F/Y513F, and S503A). Our data suggest that pp120/HA4 is part of a complex of proteins required for receptor-mediated internalization of insulin. It is possible that this function is regulated by insulin-induced phosphorylation of the intracellular domain of pp120/HA4.     

PEDF (pigment epithelium-derived factor) promotes increase and maturation of pigment granules in pigment epithelial cells in neonatal albino rat retinal cultures

AIMS: To clarify the association of p53 and CD34 expression with development of malignant solitary fibrous tumour we have studied 10 cases of solitary fibrous tumour arising in the pleura, retroperitoneum and pelvic cavity with clinicopathological features of malignancy. METHODS AND RESULTS: Tumours were localized solid masses with or without necrosis in eight and they nearly totally occupied the pleural cavity in two. Basic histology of the tumours was the proliferation of spindle cells arranged in 'patternless' pattern or in interlacing bundles with nuclear atypia and mitotic activities of various degree. In two, high-grade foci were present within low or intermediate-grade tumours. Recurrent tumours also showed more atypical features than primary tumours in two. Immunohistochemical studies showed CD34 positivity in seven, but three of them showed marked diminution or complete loss of CD34 expression in high-grade foci or a recurrent tumour. Three high-grade cases showed totally negative staining for CD34. p53 was strongly expressed in cases with fatal outcome, clinical recurrence, nuclear atypia, high mitotic activity or local invasion, whereas almost negative in benign tumours. CONCLUSIONS: Malignant solitary fibrous tumours may occur de novo or by transformation within benign or low-grade tumours and may be associated with p53 mutation. Although CD34 is a useful marker in the diagnosis of solitary fibrous tumour, one should bear in mind that its expression can be lost in high-grade tumours.     

Personalizing Politics: A Congruency Model of Political Preference.

Modern politics become personalized as individual characteristics of voters and candidates assume greater importance in political discourse. Although personalities of candidates capture center stage and become the focus of voters' preferences, individual characteristics of voters, such as their traits and values, become decisive for political choice. The authors' findings reveal that people vote for candidates whose personality traits are in accordance with the ideology of their preferred political party. They also select politicians whose traits match their own traits. Moreover, voters' traits match their own values. The authors outline a congruency model of political preference that highlights the interacting congruencies among voters' self-reported traits and values, voters' perceptions of leaders' personalities, politicians' self-reported traits, and programs of favored political coalitions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Celiac disease and autoimmunity: state of the art]

Coeliac disease is probably an immunologic disease of the small intestine which is caused by a gluten intake as promoting agent in genetically predisposed persons. Many authors described this autoimmune assumption: most of coeliac patients carry the HLA type, HLA-DQ (alpha 1 x 0501, beta 1 x 0201) etherodimer; it was found a correlation between disease specific antibodies antigliadin (AGA), antireticulin (ARA) and antiendomysium (AEA). Therefore an increase of autoantibodies and lymphocytes in the blood of coeliacs suggest the autoimmune nature of coeliac disease.     

Magnetic resonance imaging at 9.4 T: the Maastricht journey

The 9.4 T scanner in Maastricht is a whole-body magnet with head gradients and parallel RF transmit capability. At the time of the design, it was conceptualized to be one of the best fMRI scanners in the world, but it has also been used for anatomical and diffusion imaging. 9.4 T offers increases in sensitivity and contrast, but the technical ultra-high field (UHF) challenges, such as field inhomogeneities and constraints set by RF power deposition, are exacerbated compared to 7 T. This article reviews some of the 9.4 T work done in Maastricht. Functional imaging experiments included blood oxygenation level-dependent (BOLD) and blood-volume weighted (VASO) fMRI using different readouts. BOLD benefits from shorter T₂* at 9.4 T while VASO from longer T₁. We show examples of both ex vivo and in vivo anatomical imaging. For many applications, pTx and optimized coils are essential to harness the full potential of 9.4 T. Our experience shows that, while considerable effort was required compared to our 7 T scanner, we could obtain high-quality anatomical and functional data, which illustrates the potential of MR acquisitions at even higher field strengths. The practical challenges of working with a relatively unique system are also discussed.

     

An ANTS heuristic for the frequency assignment problem

The problem considered in this paper consists in assigning frequencies to radio links between base stations and mobile transmitters in order to minimize the global interference over a given region. This problem is NP-hard and few results have been reported on techniques for solving it to optimality. We have applied to this problem an ANTS metaheuristic, that is, an approach following the ant colony optimization paradigm. Computational results, obtained on a number of standard problem instances, testify the effectiveness of the proposed approach.     

Effectiveness of keyword-based display and selection of retrieval results for interactive searches

We present an approach to increasing the effectiveness of ranked-output retrieval systems that relies on graphical display and user manipulation of “views” of retrieval results, where a view is the subset of retrieved documents that contain a specified subset of query terms. This approach has been implemented in a system named VIEWER (VIEwing WEb Results), acting as an interface to available search engines. An experimental evaluation of the performance of VIEWER in contrast to AltaVista is the major focus of the paper. We first report the results of an experiment on single, short query searches where VIEWER, used as an interactive ranking system, markedly outperformed AltaVista. We then concentrate on a more realistic searching scenario, involving free query formulation, unconstrained selection of retrieval results, and possibility of query reformulation. We report the results of an experiment where the use of VIEWER, compared to AltaVista, seemed to shift the user effort from inspection to evaluation of results, increasing retrieval effectiveness, and user satisfaction. In particular, we found that the VIEWER users retrieved half as many nonrelevant documents as the AltaVista users while retrieving a comparable number of relevant documents. Published online: 22 September 2000