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Single wall carbon nanotubes (SWNTs) are considered to be one of the potential candidates for the production of transparent conducting films (TCFs), which can be used in many applications, e.g., touch panels, displays, and polymer solar cells. However, for making optimum usage of the superior properties of SWNTs, a better understanding on the processing and fabrication of thin films is essential. In this work, the effects of the purification conditions of SWNTs, the stability of their dispersions as a function of pH, and the performance of TCFs fabricated from dispersions of different pH are studied. The figure of merit σdc/σoc for such films can be increased by factor of 2 when the pH of the SWNT dispersion is increased, i.e., the optical and electrical performance is improved significantly. We also report the surface charge-manipulated transformations in transparent conducting films fabricated from SWNT dispersions of different pH values.

Belatacept was recently evaluated in liver transplantation (LT) in a phase II multicenter trial, which was terminated prematurely. Patients were more than two yr post-LT at the time. As high rates of spontaneous tolerance after LT have been reported and as belatacept has marked immunomodulatory effects, we decided to maintain the belatacept patients enrolled at our center (n = 4) on MMF monotherapy. All belatacept patients on MMF monotherapy developed graft dysfunction consistent with acute rejection after a mean period of 10.3 (7-14) wk. Patients were therefore switched to triple therapy with CNI, MMF, and corticosteroids. Graft dysfunction resolved within 1-3 wk after switch. At the time of belatacept discontinuation, mean eGFR was 105.1 mL/min/1.73 m² (92.1-118.9) in belatacept patients compared to 58 mL/min/1.73 m² (36.1-98.2) in controls (p = 0.022). One yr after the switch to CNI therapy, eGFR had declined by 27.4 mL (19.2-39.3; p = 0.008). Thus, LT patients treated with belatacept show superior kidney function that declines upon institution of CNIs. MMF monotherapy following withdrawal of belatacept is associated with a high incidence of graft dysfunction. Belatacept has no obvious immunomodulatory effects in LT recipients that would be sufficient to allow drug withdrawal with a high rate of success.

Summary Although chronological donor age is the most potentpredictor of long-term outcome after renal transplantation,it does not incorporate individual differences of the aging-process itself. We therefore hypothesized that an estimateof biological organ age as derived from markers of cellularsenescence in zero hour biopsies would be of higherpredictive value. Telomere length and mRNA expressionlevels of the cell cycle inhibitors CDKN2A (p16INK4a) andCDKN1A (p21WAF1) were assessed in pre-implantationbiopsies of 54 patients and the association of these andvarious other clinical parameters with serum creatinineafter 1 year was determined. In a linear regression analysis,CDKN2A turned out to be the best single predictorfollowed by donor age and telomere length. A multiplelinear regression analysis revealed that the combinationof CDKN2A values and donor age yielded even higherpredictive values for serum creatinine 1 year after trans-plantation. We conclude that the molecular aging markerpredict renal allograft function after 1 year significantlybetter than chronological donor age alone.Key words: biological organ age, CDKN1A, CDKN2A, kidneytransplantation, long-term allograft function, telomerelength, zero hour biopsy.

The bidirectional NiFe-hydrogenase of Synechocystis sp. PCC 6803 is encoded by five genes (hoxEFUYH) which are transcribed as one unit. The transcription of the hox-operon is regulated by a promoter situated upstream of hoxE. The transcription start point was located at -168 by 5'Race. Several promoter probe vectors carrying different promoter fragments revealed two regions to be essential for the promoter activity. One is situated in the untranslated 5'leader region and the other is found -569 to -690 nucleotides upstream of the ATG. The region further upstream was shown to bind a protein. Even though an imperfect NtcA binding site was identified, NtcA did not bind to this region. The protein binding to the DNA was purified and found to be LexA by MALDI-TOF. The complete LexA and its DNA binding domain were overexpressed in Escherichia coli. Both were able to bind to two sites in the examined region in band-shift-assays. Accordingly, the hydrogenase activity of a LexA-depleted mutant was reduced. This is the first report on LexA acting not as a repressor but as a transcriptional activator. Furthermore, LexA is the first transcription factor identified so far for the expression of bidirectional hydrogenases in cyanobacteria.

An efficient and effective system for natural language processing (NLP) was developed for improving free text analysis. The main linguistic ideas and the global system architecture are described. For improving effectiveness while keeping efficiency high we made use of principled techniques from empirical linguistics. This means that all rules are evaluated and the rule system is kept as small as possible. The approach is exemplified by the analysis of conjunctions

Problems encountered under the syntactic analysis of free text documents are discussed. The system called COPSY (context operator syntax), which uses natural language processing techniques during fully automatic syntactic analysis (indexing and search) of free text documents is described. Applications under real world conditions are mentioned as well as evaluation and technical aspects. Further developments in the field of thesaurus building and full-text analysis using the linguistic algorithms of the syntactic retrieval system are outlined. COPSY was developed as part of a text processing project at Siemens, called TINA (Text-Inhalts-Analyse: text content analysis)