Conservative management of abdominal injuries: audit of criteria for discharge

Four patients with xanthogranulomatous pyelonephritis were found to have renocolic fistulae. Coincidentally, the left kidney was involved in all four cases. All patients presented with renal mass. Two cases have had coexistent renal stones, one of them presented with massive upper gastrointestinal bleeding as a result of portal hypertension. Another patient had a history of Schistosomiasis. In none of the patients was the renal condition confidently diagnosed preoperatively, nor was the colonic fistula suspected. In all four patients, nephrectomy was performed together with resection of the involved colon followed by a satisfactory recovery. The possibility of a colonic fistula should be kept in mind as a complication to this rare renal condition in spite of the absence of colonic symptoms and normal finding in barium enema studies.     

Spatially resolved drying kinetics of multi-component solution cast films for organic electronics

The use of multi-component solvent/additive systems can be beneficial in the manufacturing process of organic and printed electronics because they can provide an extended degree of freedom, in terms of optimized wetting properties or their influence on the molecular ordering during solvent evaporation. For a systematic investigation of the drying process of such systems a technique for the measurement of the evaporation kinetics for micrometer to nanometer thin films is required. Since large area films are drying faster at the edges, we determine the drying kinetics spatially resolved in a linear array of 5 reflectometers simultaneously for single and binary solvent systems for polymer–fullerene (P3HT:PCBM) solutions as used in organic photovoltaic.In order to design a specific drying process, e.g. combined fast and slow evaporation of high or less solving solvents, a spatial resolved numerical investigation of solvent mass transfer is addressed. A numerical approach including the effect of a moving drying front shows reasonable agreement for single and binary solvent systems with spatially resolved experimental data. The effect of the moving drying front accelerates the drying kinetics at a distinct position as the front approaches and must also be considered for integral measurements (e.g. gravimetric experiments).     

Flüssigkeitsring-Vakuumpumpen

Liquid ring vacuum pumps – Oldtimers of vacuum technology and yet highly up-to-date Liquid ring vacuum pumps were developed over a hundred years ago. In the meantime, vacuum technology has evolved considerably and offers optimum economic and technical solutions for a wide variety of applications. However, liquid ring vacuum technology still has its reason for existence and is the most suitable principle for vacuum generation in some applications. Thanks to its functionality it is perfectly suited for the extraction of humid gases or vapours. Due to the use of process-compatible operating fluid and the possibility of different construction materials, it can be perfectly matched to different operating fluids and process conditions. In addition, it is available in many sizes on the market and can therefore extract very small and very high quantities of gas and vapour.     

Solution processable,precursor based zinc oxide buffer layers for 4.5% efficient organic tandem solar cells

In this work we present regular and inverted organic tandem solar cells from poly[N-9′-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole): [6,6]-phenyl C₇₀-butyric acid methyl ester (PCDTBT:PC₇₁BM) with power conversion efficiencies of up to 4.5%. The recombination zone comprises an electron conducting, precursor based zinc oxide buffer layer that was applied from solution under ambient conditions and at moderate processing temperatures. Optimized active layer thicknesses in both subcells were derived from optical Transfer Matrix simulations. The short circuit current density of the tandem cell exceeds half the short circuit current density of the single absorber cells indicating a real gain in quantum yield when utilizing the tandem architecture.     

Verwaltung und Auswertung von Umkehrosmose‐Anlagendaten zur statistischen Voraussage

Two options are presented to evaluate the performance of a reverse osmosis system. The first possibility is based on a comparison calculation with a design software. This method is helpful when only a limited amount of data is available. As a second possibility the normalization is evaluated. For normalization, Microsoft Excel is often used as a tool. However, an Excel evaluation is difficult especially for large amounts of data and does not provide sufficient protection against manipulation. A new data software that enhances this is presented.     

PASylated Thymosin α1: A Long-Acting Immunostimulatory Peptide for Applications in Oncology and Virology

Thymosin α1 (Tα1) is an immunostimulatory peptide for the treatment of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections and used as an immune enhancer, which also offers prospects in the context of COVID-19 infections and cancer. Manufacturing of this N-terminally acetylated 28-residue peptide is demanding, and its short plasma half-life limits in vivo efficacy and requires frequent dosing. Here, we combined the PASylation technology with enzymatic in situ N-acetylation by RimJ to produce a long-acting version of Tα1 in Escherichia coli at high yield. ESI-MS analysis of the purified fusion protein indicated the expected composition without any signs of proteolysis. SEC analysis revealed a 10-fold expanded hydrodynamic volume resulting from the fusion with a conformationally disordered Pro/Ala/Ser (PAS) polypeptide of 600 residues. This size effect led to a plasma half-life in rats extended by more than a factor 8 compared to the original synthetic peptide due to retarded kidney filtration. Our study provides the basis for therapeutic development of a next generation thymosin α1 with prolonged circulation. Generally, the strategy of producing an N-terminally protected PASylated peptide solves three major problems of peptide drugs: (i) instability in the expression host, (ii) rapid degradation by serum exopeptidases, and (iii) low bioactivity because of fast renal clearance.     

Catalytic materials manufactured by the polyol process for monolithic dye‐sensitized solar cells

Three types of screen‐printable catalytic pastes were successfully prepared to be used as counterelectrode for monolithic dye solar cells encapsulated with glass frit. The electroless bottom‐up method or so‐called polyol process has been applied to fabricate thermally stable SnO₂:Sb/Pt and carbon black/Pt nanocomposites. The catalytic and electric properties of these materials were compared with a new platinum‐free type of carbon counterelectrode. The layers containing low platinum amounts (less than 5 µg/cm²) exhibit a very low charge transfer resistance of about 0·4 Ω · cm². Also the conductive carbon layer shows an acceptable charge transfer resistance of 1·6 Ω · cm². Additionally the catalytic layer containing porous carbon black reveals excellent sheet resistance below 5 Ω/□; this feature has enabled to work out a low cost counterelectrode which combined suitable catalytic and conductive properties. The layers have been characterized using following methods: electrochemical impedance spectroscopy (EIS), field emission scanning electron microscopy (FE‐SEM), energy filter transmission electron microscopy (EF‐TEM) and inductively coupled plasma mass spectroscopy (ICP‐MS). Copyright © 2008 John Wiley & Sons, Ltd.     

Integration of organic semiconductor lasers and single-mode passive waveguides into a PMMA substrate

Efficiently combining active and passive elements in integrated optics is a key ingredient for their successful employment. Here, we present the fabrication of an optimized PMMA substrate structure for improved coupling of laser light generated by organic semiconductor distributed feedback lasers into single-mode deep ultraviolet induced waveguides. For production, electron beam lithography on an oxidized silicon wafer and subsequent reactive ion etching is used to form the feedback grating of the laser. Afterwards, an aligned second electron beam lithography step on top of the grating allows the fabrication of a topographical step of 1.67 μm on the edges of the grating area. Metal is evaporated on this resulting master structure serving as a plating base for electroforming of a Ni tool. The tool is then used for hot embossing of the structure into PMMA bulk material. On a length of 500 μm the imprinted grating lines, having a period of 200 nm, are 100 nm wide and 60 nm high. Aligned deep ultraviolet exposure to induce a passive single- or multi-mode waveguide and co-evaporation of the active material Alq₃:DCM finish the coupling region. This structure optimizes the coupling of laser light generated in the laser structure into the passive waveguide. In combination with microfluidic channels, the laser light can be considered for sensing applications on a PMMA lab-on-chip system.     

Solution-processed polymer–silver nanowire top electrodes for inverted semi-transparent solar cells

We present a transparent, fully solution-processed top anode system comprising a thin, conductive polymer interlayer below a silver nanowire mesh for efficient organic electronic devices. We fabricate inverted semi-transparent polymer solar cells exhibiting power conversion efficiencies that are comparable to devices incorporating an opaque electrode. By means of scanning electron microscopy and light beam induced photocurrent measurements we show that the thin polymer interlayer facilitates charge extraction from the active layer and efficient transport to the metallic nanowire mesh.