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This paper reports on the light amplification of NaGdF4:Yb,Er,Ce@NaGdF4:Yb,Nd@NaGdF4 core–shell–shell downconversion nanoparticles (CSS-DCNPs) in the near-infrared second biological window (NIR-II: 1000–1700 nm) by plasmonic nanostructures. Through a precisely controlled plasmonic metallic nanostructure, fluorescence from Yb3+ induced 1000 nm emission, Nd3+ induced 1060 nm emission, and Er3+ induced 1527 nm emission are enhanced 1.6-fold, 1.7-fold, and 2.2-fold, respectively, under an 808 nm laser excitation for the CSS-DCNPs coupled with a gold hole-cap nanoarray (Au-HCNA), while the Er3+ induced 1527 nm emission under a 980 nm laser excitation is enhanced up to 6-fold. To gain insight into the enhancement mechanism, the plasmonic modulation of Er3+ induced NIR-II emission at 1550 nm under 980 nm excitation is studied by FDTD simulation and lifetime measurements, showing the observed fluorescence enhancement can be attributed to a combination of enhanced excitation and an increased radiative decay rate.

Nacre, a ceramic composite found in seashells, has baffled scientists due to its extraordinary mechanical properties. Consequently, nacre has been a main source of inspiration to create strong and tough ceramic composites that mimic nacre’s microstructure. The precise microstructural features responsible for its unique combination of high strength and toughness are however debated, and efforts to mimic and improve upon nature’s design have not led to commercial applications of ceramic nacre-like composites. This dissertation details the replication of nacre’s microstructural architecture with technical ceramics and nanomaterials. Instead of nacre’s calcium carbonate building blocks, alumina was used, and instead of its organic phase, multi-walled carbon nanotubes (MWCNTs) were incorporated. To design a nacreous microstructure, freeze casting of alumina nanoparticles was used to template a microstructure of aligned lamellae over macroscopic length scales. Although successful, the fabricated lamellar microstructures’ macroscopic orientation was hard to consistently reproduce using this technique and the resulting composites, unlike nacre, fail in a completely brittle fashion. Therefore, alumina platelets that closely resemble the platelets in nacre were investigated. A recipe to homogeneously coat these platelets in situ with MWCNT was developed, and MWCNT growth and catalyst modification was studied in-depth. The resulting combined building blocks were sintered into a composite that displays a graceful failure mechanism like nacre does, with several toughening mechanisms observed to be active. In addition, nacre-like alumina/MWCNT composite materials have been synthesised using a variety of MWCNT dispersion techniques. All studied nacre-like composites showed characteristic macroscopic interlocking behaviour and remain interlocked after crack initiation which prevented complete failure and gave these composites a residual strength. Pure nacre-like alumina specimens have also been tested in high strain rate and impact tests, where these materials showed a significant improvement over nontextured alumina.

© 2019 The Authors A novel building block material for the generation of non-brittle ceramic composites consisting of micron-sized alumina platelets homogeneously coated with multi-wall carbon nanotubes (MWCNTs) bound to their surface is described. The MWCNT phase is grown in situ from immobilised metal catalyst particles using chemical vapour deposition techniques. In-depth Raman and scanning electron microscope studies revealed that this approach solves the typical issue of MWCNT-agglomeration in ceramic matrices and paves the way to excellent control over MWCNT purity and concentration within the resulting composite material. Moreover, we show that the preparation of the catalyst is the most important factor for the generation of uniformly distributed MWCNTs of high-quality on these platelets. With these MWCNT-coated alumina building blocks, we have manufactured nacre-like biomimetic composites using spark plasma sintering. The resulting composites are electrically conductive and three-point bending tests show a transition from brittle/catastrophic failure to graceful failure, holding great promise towards multifunctional, tough and strong lightweight ceramic composite manufacturing.

Pacts for employment and competitiveness are an integral component of the ongoing process of decentralization of collective bargaining in Germany, a phenomenon that has been hailed as key to that nation's economic resurgence. Yet little is known about the effects of pacts on firm performance. The evidence largely pertains to employment and is decidedly mixed. This article investigates the association between pacts and six outcome indicators using a framework in which the controls comprise establishments that negotiated over pacts but failed to reach agreement on their implementation. An extensive set of robustness checks are run to test the sensitivity of the key findings of the model. There is no suggestion of pacts negatively impacting any of the selected measures of establishment performance. Rather, the evidence points to some positive short- and medium-run effects on firm average wages and possibly employment and innovation as well.

Science and philosophy still lack an overarching theory of consciousness. We suggest that a further step toward it requires going beyond the view of the brain as input-output machine and focusing on its intrinsic activity, which may express itself in two distinct modalities, i.e. aware and unaware. We specifically investigate the predisposition of the brain to evaluate and to model the world. These intrinsic activities of the brain retain a deep relation with consciousness. In fact the ability of the brain to evaluate and model the world can develop in two modalities, implicit or explicit, that correspond to what we usually refer to as the unconscious and consciousness, and both are multilevel configurations of the brain along a continuous and dynamic line. Starting from an empirical understanding of the brain as intrinsically active and plastic, we here distinguish between higher cognitive functions and basic phenomenal consciousness, suggesting that the latter might characterize the brain’s intrinsic activity as such, even if at a very basic level. We proceed to explore possible impacts of the notion of intrinsic cerebral phenomenality on our understanding of consciousness and its disorders, particularly on the diagnosis and management of patients with disorders of consciousness.

Innovationen gelten als Triebfeder der wirtschaftlichen Entwicklung und der betrieblichen Wettbewerbsfähigkeit. Von besonderem Interesse sind Produkte, die ein Unternehmen erstmals in den Markt einführt bzw. für die das Unternehmen einen neuen Markt erschließen muss. Diese Innovationen bezeichnet man als Marktneuheiten. Aus ökonomischer Sicht stellt sich die Frage, ob Unternehmen, die solche Marktneuheiten hervorbringen, erfolgreicher sind als nicht innovierende Unternehmen. Als Erfolgsindikatoren lassen sich die Entwicklung der Beschäftigung, des Umsatzes, des Gewinns und der Ertragslage heranziehen. Die zu vergleichenden innovierenden und nicht innovierenden Unternehmen sollten aber in ihren sonstigen betrieblichen Merkmalen (wie der Größe oder Branche) auch tatsächlich miteinander vergleichbar sein. Dies wird mit einem Matching-Verfahren erreicht. Die Ergebnisse der mit dem IAB-Betriebspanel für das Verarbeitende Gewerbe durchgeführten Analyse zeigen, dass sich im Durchschnitt die innovierenden Betriebe in den Neuen Ländern im Vergleich zu nicht innovierenden Betrieben durch einen Vorsprung bei der Entwicklung von Beschäftigung und Umsatz auszeichnen. Dieser Abstand ist bei Betrieben in Ostdeutschland etwas größer als bei Betrieben in den Alten Bundesländern. Mit Blick auf die Produktivitätsentwicklung und die Ertragslage finden sich keine statistisch belastbaren Unterschiede zwischen Innovatoren und Nicht-Innovatoren. Die Ergebnisse stellen die hohe Bedeutung von Innovationen für die wirtschaftliche Entwicklung und Wettbewerbsfähigkeit nicht infrage. Sie liefern aber einen Hinweis darauf, dass – bezogen auf Marktneuheiten – auch nicht innovierende Unternehmen (zumindest mittelfristig) Wege finden, sich in ihrer betrieblichen Performance zu behaupten.

The aim of this study was to investigate the expression and prognostic influence of HER1 (EGFR), HER2 (c-erb-B2), HER3 (c-erb-B3) and HER4 (cerb-B4) in squamous cell cervical carcinomas (SCC) and the importance of receptor correlations.78 SCC were stained immunohistochemically for HER1-HER4. HER2 gene amplification was determined using fluorescence in situ hybridization (FISH). Parametric correlations were performed between the four receptors and tumor characteristics. Overall survival was evaluated by uni- and multivariate analyses.Overexpression was found in 63% of SCC for HER1, in 21.8% for HER2, in 74.4% for HER3 and in 79.5% for HER4. Correlations were observed between HER1 and HER4 (p = 0.019). Survival analyses revealed a significant association of HER1 overexpression with favorable outcome (p = 0.016), while overexpression of HER2 and HER3 was associated with poor prognosis (p = 0.006; p = 0.05, respectively). HER1 remained significant in multivariate analysis.These data suggest that the prognostic relevance of the different HER receptors is influenced by the balance between the various receptors, especially of HER4.