Silicon micro venturi nozzles for cost-efficient spray coating of thin organic P3HT/PCBM layers

Improvements on spray coating are of particular interest to different fields of technology as it is a scalable deposition method and processing from solutions offer various application possibilities outside of typical facilities. When it comes to the deposition of expensive and film-forming media such as organic semiconductors, consumption and nozzle cleaning issues are of particular importance. We demonstrate the simple steps to design and fabricate micro venturi nozzles for economical spray coating with a consumption as low as 30-50 µl centerdot min$^{-1}$. For spray coating an active area of 25 cm$^{2}$ a 2.45-4.01 fold coating efficiency is observed compared to a conventional airbrush nozzle set. The electrical characterization of first diodes sprayed with an active layer thickness of ~750 nm using a single micronozzle at a coating speed of 1.7 cm2 centerdot min−1 reveals a good external quantum efficiency of 72.9% at 532 nm and a dark current of ~7.4 centerdot 10$^{-5}$ mA centerdot cm$^{-2}$, both measured at  −2 V. Furthermore, the high resistance of the micronozzles against solvents and most acids is provided through realization in a silicon wafer with silicon dioxide encapsulation, therefore allowing easy and effective cleaning

The Headgroup (A)Symmetry Strongly Determines the Aggregation Behavior of Single-Chain Phenylene-Modified Bolalipids and Their Miscibility with Classical Phospholipids

In the present work, we describe the synthesis of two single-chain phenylene-modified bolalipids, namely PC-C17pPhC17-PC and PC-C17pPhC17-OH, with either symmetrical (phosphocholine) or asymmetrical (phosphocholine and hydroxyl) headgroups using a Sonogashira cross-coupling reaction as key step. The temperature-dependent aggregation behavior of both bolalipids in aqueous suspension was studied using transmission electron microscopy (TEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, small angle neutron scattering (SANS), and X-ray scattering. We show that different headgroup symmetries lead to a change in the aggregation behavior: Whereas PC-C17pPhC17-PC forms nanofibers with a diameter of 5.7 nm that transform into small ellipsoidal micelles at 23 °C, the PC-C17pPhC17-OH self-assembles into lamellae with bolalipid molecules in an antiparallel orientation up to high temperatures. Furthermore, the mixing behavior of both bolalipids with bilayer-forming phospholipids (DPPC and DSPC) was studied by means of DSC and TEM. The aim was to stabilize bilayer membranes formed of phospholipids in order to improve these mixed lipid vesicles for drug delivery purposes. We show that the symmetrical PC-C17pPhC17-PC is miscible with DPPC and DSPC; however, closed lipid vesicles are not observed, and elongated micelles and bilayer fragments are found instead. In contrast, the asymmetrical PC-C17pPhC17-OH shows no miscibility with phospholipids at all

Betonieren unter Verkehr: Untersuchung der Auswirkungen von Erschütterungen auf jungen Beton

Im vorgestellten Beitrag wird der Einfluss von Erschütterungen auf den jungen Beton systematisch und anhand von realistischen Versuchen an Kleinkörpern aus unbewehrtem und bewehrtem Beton behandelt. Die kontrollierte dynamische Anregung erfolgt künstlich mit dem AIT-Schwingungsgenerator. Die Proben (zwei verschiedene Betonsorten: „Standard-Brückenbeton“ B3-C30/37 und „Randbalkenbeton“ B7-C25/30) werden während der Erhärtungsphase systematisch mit harmonischen als auch mit realen verkehrsinduzierten Brückenschwingungsverläufen beaufschlagt. Variiert werden Intensitäten und Frequenzgehalt sowie Signalform. Im Anschluss werden die Materialparameter bestimmt und mit ruhend gelagerten Referenzköpern verglichen. Erste Ergebnisse zeigen, dass die mechanischen Eigenschaften Druckfestigkeit und E-Modul wenig oder nur gering beeinflusst werden. Dauerhaftigkeitstests und Untersuchungen am Mikrogefüge dienen dazu, Fehler, Risse und Veränderungen im Gefüge zu identifizieren und werden im laufenden Forschungsprojekt noch weiter durchgeführt. Auswirkungen auf den Verbund zwischen Beton und Bewehrung werden durch Auszugversuche analysiert. Bei diesen Versuchen wurden bei größeren Relativbewegungen zwischen Beton und Bewehrungsstab Abnahmen der mittleren Verbundfestigkeit beobachtet. Bei geringeren Relativverschiebungen (Amplituden von ca. 0,14 mm bei Dauerverkehr) konnte die Verbundfestigkeit hingegen sogar gesteigert werden

Immunotherapy in head and neck cancer - scientific rationale, current treatment options and future directions

Head and neck squamous cell carcinoma (HNSCC) is a frequent tumour arising from multiple anatomical subsites in the head and neck region. The treatment for early-stage disease is generally single modality, either surgery or radiotherapy. The treatment for locally advanced tumours is multimodal. For recurrent/metastatic HNSCC palliative chemotherapy is standard of care. The prognosis is limited and novel treatment approaches are urgently needed. HNSCC evades immune responses through multiple resistance mechanisms. HNSCC is particularly characterised by an immunosuppressive environment which includes the release of immunosuppressive factors, activation, expansion of immune cells with inhibitory activity and decreased tumour immunogenicity. An in-depth understanding of these mechanisms led to rational design of immunotherapeutic approaches and clinical trials. Currently, only immune checkpoint inhibitors, namely monoclonal antibodies targeting the immune inhibitory receptor programmed cell death 1 (PD-1) and its ligand PD-L1 have proven clinical efficacy in randomised phase III trials. The PD-1 inhibitor nivolumab is the only drug approved for platinum-refractory recurrent/metastatic HNSCC. However, many more immunotherapeutic treatment options are currently under investigation. Ongoing trials are investigating immunotherapeutic approaches also in the curative setting and combination therapies using different immunotherapeutic approaches. This review article summarises current knowledge of the role of the immune system in the development and progression of HNSCC, and provides a comprehensive overview on the development of immunotherapeutic approaches

The missing link: Bordetella petrii is endowed with both the metabolic versatility of environmental bacteria and virulence traits of pathogenic Bordetellae

Gross R, Guzman CA, Sebaihia M, et al. The missing link: Bordetella petrii is endowed with both the metabolic versatility of environmental bacteria and virulence traits of pathogenic Bordetellae. BMC Genomics. 2008;9(1): 449.Background: Bordetella petrii is the only environmental species hitherto found among the otherwise host-restricted and pathogenic members of the genus Bordetella. Phylogenetically, it connects the pathogenic Bordetellae and environmental bacteria of the genera Achromobacter and Alcaligenes, which are opportunistic pathogens. B. petrii strains have been isolated from very different environmental niches, including river sediment, polluted soil, marine sponges and a grass root. Recently, clinical isolates associated with bone degenerative disease or cystic fibrosis have also been described. Results: In this manuscript we present the results of the analysis of the completely annotated genome sequence of the B. petrii strain DSMZ12804. B. petrii has a mosaic genome of 5,287,950 bp harboring numerous mobile genetic elements, including seven large genomic islands. Four of them are highly related to the clc element of Pseudomonas knackmussii B13, which encodes genes involved in the degradation of aromatics. Though being an environmental isolate, the sequenced B. petrii strain also encodes proteins related to virulence factors of the pathogenic Bordetellae, including the filamentous hemagglutinin, which is a major colonization factor of B. pertussis, and the master virulence regulator BvgAS. However, it lacks all known toxins of the pathogenic Bordetellae. Conclusion: The genomic analysis suggests that B. petrii represents an evolutionary link between free-living environmental bacteria and the host-restricted obligate pathogenic Bordetellae. Its remarkable metabolic versatility may enable B. petrii to thrive in very different ecological niches