Electron correlations are known to play an important role in determining the unusual physical properties of a variety of compounds. Such properties include high-temperature superconductivity, heavy fermion behaviour and metal-to-insulator transitions. High-resolution photoelectron spectroscopy (PES) provides a means of directly probing the electronic states (particularly those near the Fermi level) in these materials, but the short photoelectron mean free paths (< or = 5 A) associated with the low excitation energies conventionally used (< or = 120 eV) make this a surface-sensitive technique. Now that high-resolution PES is possible at much higher energies, with mean free paths as long as 15 A (ref. 6), it should become feasible to probe the bulk electronic states in these materials. Here we demonstrate the power of this technique by applying it to the cerium compounds CeRu2Si2 and CeRu2. Previous PES studies of these compounds revealed very similar spectra for the Ce 4f electronic states, yet it is expected that such states should be different owing to their differing degrees of hybridization with other valence bands. Our determination of the bulk Ce 4f electronic states of these compounds resolves these differences.

The thermal decomposition of a radical initiator, AIBN in a microreactor was examined. The plots of unchanged AIBN against the residence time fitted well to the calculated one based on the bath temperature, indicating the efficient heat transfer through the wall of the microreactor by virtue of a high surface-to-volume ratio. The effectiveness of the microreactor on the molecular weight distribution control was then examined. For the polymerization of butyl acrylate (BA), the polydispersity index (PDI) of the polymer obtained using the microreactor was much smaller than that obtained with a macroscale batch reactor. The result can be explained in terms of much higher heat removal efficiency of the microreactor compared with the macroscale batch reactor. For the polymerization of benzyl methacrylate (BMA) and methyl methacrylate (MMA), the effect of the microreactor on PDI was smaller than in the case of BA. For the polymerization of vinyl benzoate (VBz) and styrene (St), no appreciable effect of microreactor on PDI was observed. These experimental results indicate that the microreactor is quite effective to the molecular weight distribution control for highly exothermic free radical polymerizations (BA, BMA, and MMA) but that it is not so effective for less exothermic polymerizations (VBz and St).

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Recently, it has been shown that approximately 80% of Merkel cell carcinomas harbor a novel polyomavirus named Merkel cell polyomavirus, thought to be a carcinogenic agent. However, it is not fully elucidated whether Merkel cell carcinomas differ with regard to the presence or absence of Merkel cell polyomavirus. To address this, we investigated morphologic differences between Merkel cell polyomavirus-positive and -negative Merkel cell carcinomas by morphometry. Using polymerase chain reaction and real-time quantitative polymerase chain reaction, Merkel cell polyomavirus was detected in 20 (77%) of 26 Merkel cell carcinoma cases, including 4 Merkel cell carcinomas combined with squamous cell carcinomas. Interestingly, Merkel cell polyomavirus was detected only in ordinary (pure) Merkel cell carcinomas; none of the 4 combined Merkel cell carcinomas + squamous cell carcinomas was positive for Merkel cell polyomavirus (P = .001). Morphometric analyses revealed that Merkel cell polyomavirus-negative Merkel cell carcinomas had more irregular nuclei (P < .001) and more abundant cytoplasm (P = .001) than Merkel cell polyomavirus-positive Merkel cell carcinomas, which had uniform round nuclei and scant cytoplasm. Reliability of the morphometry was confirmed using intraobserver and interobserver reliability tests. These results demonstrated statistically significant differences in tumor cell morphology between Merkel cell polyomavirus-positive and -negative Merkel cell carcinomas and reconfirmed the absence of Merkel cell polyomavirus in combined tumors. Furthermore, the results strongly suggest fundamental biological differences between Merkel cell polyomavirus-positive and -negative Merkel cell carcinomas, supporting that Merkel cell polyomavirus plays an important role in the pathogenesis of Merkel cell polyomavirus-positive Merkel cell carcinoma.

ContentsCover: Interdigital Micromixer HPIMM for high pressure and high temperature applications. With Courtesy of Institut für Mikrotechnik Mainz GmbH, Germany. Editorial:From Review: Efficient micromixing possible with a short diffusion path increases the product selectivity of competitive parallel reactions and competitive consecutive reactions. This concept has been expanded to control the molecular weight and molecular weight distribution in carbocationic polymerization. The efficient heat transfer, based on high surface to volume ratios, allows precise temperature control and is also effective for the control of highly exothermic reactions, such as free radical polymerization. Review: Microstructured reactors have the potential to change industrial chemical production. The main arguments for using microstructured reactors are enhanced conversion and selectivity, increased spacetime yields, waste reduction, and better safety given by the small reactor volumes. Credit-card sized reaction systems allow to perform the screening of multi-step reactions in one run. This essay focuses on the grouping and benchmarking of current works and the evaluation and direct comparison to established technology. Organic Synthesis with Microstructured Reactors