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The morphological evolution of thin composite films based on poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C 61 butyric acid methyl ester (PCBM) upon annealing has been studied by means of transmission electron microscopy (TEM), scanning near-field optical microscopy (SNOM), and confocal Raman microscopy. This system currently is the most promising candidate for high-performance polymer solar cells. TEM bright field and SNOM topography measurements show that segregation and large-scale crystallization of PCBM take place upon thermal annealing. Additional SNOM optical absorbance measurements using laser irradiation sources with two different wavelengths in the visible light range and Raman microscopy are able to detect the component distribution within the thin composite film, which in detail demonstrates high diffusive mobility of PCBM upon annealing.

Postoperative irradiation with wIRA can improve normal postoperative wound healing and may reduce costs in gastrointestinal surgery.

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SummaryHere we describe the use of pulse-mode scanning ion conductance microscopy (SICM) to observe volume changes and cell membrane movements during the locomotion of cultured cells in the range of minutes to several hours. The microscope is based on the pulse-mode SICM previously developed for stable imaging of single cells in culture. Our instrument uses current pulses to control the distance between cell surface and electrode tip as well as a back-step mode to prevent contact of tip and membrane during lateral movements of the probe. We performed repeated scans of cell surfaces using feedbackcontrolled piezoactors to position the electrode. Using patchclamp-type electrode tips the height of cells could reproducibly be measured with a standard deviation of 50 nm. To quantify and separate changes in cell position and volume occurring between consecutive scans, a program was written to subtract images and calculate volume changes. Examples of repeated scans show that membrane movements in the range of 30 min to a few hours can be quantitatively monitored with a lateral resolution of 500 nm using difference images and that faster movements in the range of minutes can be recorded at defined cell sections using the line scan mode. Difference images indicate that volume changes can affect cell surfaces inhomogeneously, emphazising the role of the cytoskeleton in the stabilization of cell shape.

Underlying near-field optical effects on the nanoscale have stimulated the development of apertureless vibrational spectroscopy and imaging with ultrahigh spatial resolution. We demonstrate tip-enhanced Raman spectra of single-walled carbon nanotubes (SWCNTs), recorded with a scanning near-field optical spectrometer using both atomic force (AF) and shear force (SF) feedback lock-in regulation, and critically discuss the advantages and drawbacks of both operation modes. For accurate calculation of the enhancement factor obtained, we have analysed the tip shape and diameter by means of scanning electron and transmission electron microscopy (SEM and TEM). In our experiments we reproducibly attain diameter-corrected and area-corrected enhancement factors of up to ∼10 4 and ∼10 5 , respectively, estimated as the linear ratio of near-and far-field intensities, and we are able to demonstrate near-field Raman imaging of SWCNTs with spatial resolution better than 50 nm.

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All treatments showed high efficacy with good cosmetic outcome and high patient satisfaction. Efficacy of treatment was better without spray cooling. VIS+wIRA PDT was less painful than LED PDT for PDT without spray cooling.