Assessing polymer-surface adhesion with a polymer collection

Polymer modification plays an important role in the construction of devices, but the lack of fundamental understanding on polymer-surface adhesion limits the development of miniaturized devices. In this work, a thermoplastic polymer collection was established using the combinatorial laser-induced forward transfer technique as a research platform, to assess the adhesion of polymers to substrates of different wettability. Furthermore, it also revealed the influence of adhesion on dewetting phenomena during the laser transfer and relaxation process, resulting in polymer spots of various morphologies. This gives a general insight into polymer-surface adhesion and connects it with the generation of defined polymer microstructures, which can be a valuable reference for the rational use of polymers

Assessing Polymer-Surface Adhesion with a Polymer Collection

Polymer modification plays an important role in the construction of devices, but the lack of fundamental understanding on polymer-surface adhesion limits the development of miniaturized devices. In this work, a thermoplastic polymer collection was established using the combinatorial laser-induced forward transfer technique as a research platform, to assess the adhesion of polymers to substrates of different wettability. Furthermore, it also revealed the influence of adhesion on dewetting phenomena during the laser transfer and relaxation process, resulting in polymer spots of various morphologies. This gives a general insight into polymer-surface adhesion and connects it with the generation of defined polymer microstructures, which can be a valuable reference for the rational use of polymers

Intraoperativer Ultraschall in der Viszeralchirurgie

Background Intraoperative ultrasound is a routine procedure in abdominal surgery. Not only detection of focal lesions but also perfusion and elasticity analyses using color-coded Doppler sonography, contrast-enhanced ultrasound and elastography enable highly sensitive and highly specific diagnostics, especially in oncological surgery. Objective This article provides an overview on current techniques of intraoperative ultrasound and gives an outlook on future possibilities and applications. Material and methods Literature-based presentation of evidence-based intraoperative ultrasound, discussion of current basic research and expert recommendations. Results Modern intraoperative ultrasound is a highly efficient technique for detection and characterization of focal space-occupying lesions in surgery of benign and malignant diseases. Conclusion Intraoperative ultrasound is a highly sensitive and specific diagnostic tool, providing real-time diagnostics with a manageable amount of technical equipment. Thus, preoperative diagnostics can be refined, partly resulting in a modification of intraoperative treatment management. Future developments in the fields of digital image fusion with preoperative sectional imaging, optical guidance of surgical instruments and molecular targeted tumor therapy will increase the importance of intraoperative sonography even more

Wasserbasierte Metallkomplex-Katalysatoren. Teilprojekt: Homogenkatalyse im Zweiphasensystem - Synthese wasserloeslicher Phosphane mit massgeschneiderter Struktur Schlussbericht

The synthetic methodology for water soluble phosphines was only poorly developed at the beginning of this project. The methods reported in the literature so far were not sufficient for a systematic approach to ligands of this type with novel structural features. Using different and complementary synthetic procedures developed by us novel types of anionic phosphines with sulfonated, carboxylated and phosphonated phenyl moieties as well as cationic types of ligands with ammonium and guanidinium substituents in their peripheries were obtained. In addition to nucleophilic phosphination of sulfonated, carboxylated and phosphonated fluorobenzene derivatives, Pd-catalyzed P-C coupling of primary and secondary phosphines with iodo- or bromobenzene derivatives bearing polar substituents could be established as a novel synthetic method of broad applicability. The structures of water soluble phosphine ligands and their complexes have been obtained by X-ray structural analysis which provided useful parameters for quantum mechanical calculations and molecular modeling of catalyst structures. p-TPPTS, m-TPPTS and guanidinium phosphines have been evaluated as catalyst ligands in Rh-catalyzed hydroformylation of n-hexene in two-phase systems. In various Pd-catalysed C-C-coupling reactions in aqueous media guanidinium phosphines proved to be of surmounting activity. (orig.)SIGLEAvailable from TIB Hannover: DtF QN1(55,3) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

High-Resolution Ultrasound Including Contrast-Enhanced Ultrasound (CEUS) for the Detection of Gas Formation during Aspergillus Fumigatus Infection in Mice

Purpose: A. fumigatus infections represent a major threat for patients with a suppressed immune system. Early diagnosis is of importance for a favorable outcome but appears to be difficult due to limited diagnostic procedures. Here we investigated the sensitivity of high-resolution ultrasound (HRU) for the detection of A. fumigatus infection in the liver. Materials and Methods: BALB/c mice were intravenously infected with A. fumigatus and monitored by HRU, Doppler sonography (CCDS), contrast-enhanced ultrasound (CEUS), and real-time strain color-coded elastography (CCE) using a multi-frequency probe (6 - 15 MHz). Contrast media bolus injection of sulfur-hexafluoride micro-bubbles was applied and digital cine-loops from the arterial phase, as well as the portal venous phase up to the late phase of the whole liver were analyzed. All data were correlated to the histopathological findings. Results: Using HRU and CEUS, a sonic shadow was detected in all infected animals. All Aspergillus-infected nodes from 3 -6mm in the liver showed a shadow with rim enhancement and no intranodal enhancement when using CEUS. A. fumigatus infection was confirmed by CFU assessment and histopathological analysis. Granulomas were not associated with shadowing on B-mode. In contrast, granulomas with a diameter above 5mm and a higher stiffness in CCE generated particularly an arterial rim enhancement and portal venous washout without contrast media uptake in the late phase. In addition, CEUS was able to define dynamic capillary microvascularization of infected liver areas. Conclusion: Liver lesions associated with A. fumigatus infection can be detected in mice when combined with CEUS and CCE in vivo

Sequence-controlled molecular layers on surfaces by thiol–ene chemistry: synthesis and multitechnique characterization

Silicon surfaces were functionalized by thiol–ene chemistry using sequential reactions of different α,ω-dienes and α,ω-dithiols bearing marker moieties.</p