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Liquid chromatography/mass spectrometry (LC/MS)-based methods were developed for the analysis of 10 resin acids and five fatty acids in process waters of paper industries. No fragmentation of target compounds was observed using atmospheric pressure chemical ionization (APCI) with negative ionization. The [M - H]- ion permitted the individual quantification of fatty and aromatic resin acids, whereas the non-aromatic resin acids presented a single and common ion at m/z 301. Separation with two columns of different polarity permitted peak confirmation. The method that used a C8 column with 2-propanol in the mobile phase allowed a certain separation and identification of the non-aromatic resin acids, whereas the method using a C18 column provided detection limits 10-fold lower for fatty acids. Limits of detection were 0.10 ng for all compounds. Direct sample introduction was compared with liquid-liquid extraction, with similar recoveries (70-101%). Whereas slightly lower detection limits were obtained with liquid-liquid extraction, better reproducibility was observed for direct sample introduction. Resin and fatty acids were determined in process waters of several paper industries. Palmitic, dehydroabietic and non-aromatic resin acids were encountered in most water samples, at levels between 22 and 403 g l-1. LC/MS with direct sample introduction was found to be a good alternative to traditional liquid-liquid extraction and gas chromatography for the analysis of such compounds since no derivatization was required and sample manipulation was minimal.

Open access (OA) publishing, whereby authors, their institutions, or their granting bodies pay or provide a repository through which peer-reviewed work is available online for free, is championed as a model to increase the number of citations per paper and disseminate results widely, especially to researchers in developing countries. We compared the number of citations of OA and non-OA papers in six journals and four books published since 2000 to test whether OA increases number of citations overall and increases citations made by authors in developing countries. After controlling for type of paper (e. g., review or research paper), length of paper, authors' citation profiles, number of authors per paper, and whether the author or the publisher released the paper in OA, OA had no statistically significant influence on the overall number of citations per journal paper. Journal papers were cited more frequently if the authors had published highly cited papers previously, were members of large teams of authors, or published relatively long papers, but papers were not cited more frequently if they were published in an OA source. Nevertheless, author-archived OA book chapters accrued up to eight times more citations than chapters in the same book that were not available through OA, perhaps because there is no online abstracting service for book chapters. There was also little evidence that journal papers or book chapters published in OA received more citations from authors in developing countries relative to those journal papers or book chapters not published in OA. For scholarly publications in conservation biology, only book chapters had an OA citation advantage, and OA did not increase the number of citations papers or chapters received from authors in developing countries.

Open access (OA) publishing, whereby authors, their institutions, or their granting bodies pay or provide a repository through which peer-reviewed work is available online for free, is championed as a model to increase the number of citations per paper and disseminate results widely, especially to researchers in developing countries. We compared the number of citations of OA and non-OA papers in six journals and four books published since 2000 to test whether OA increases number of citations overall and increases citations made by authors in developing countries. After controlling for type of paper (e. g., review or research paper), length of paper, authors' citation profiles, number of authors per paper, and whether the author or the publisher released the paper in OA, OA had no statistically significant influence on the overall number of citations per journal paper. Journal papers were cited more frequently if the authors had published highly cited papers previously, were members of large teams of authors, or published relatively long papers, but papers were not cited more frequently if they were published in an OA source. Nevertheless, author-archived OA book chapters accrued up to eight times more citations than chapters in the same book that were not available through OA, perhaps because there is no online abstracting service for book chapters. There was also little evidence that journal papers or book chapters published in OA received more citations from authors in developing countries relative to those journal papers or book chapters not published in OA. For scholarly publications in conservation biology, only book chapters had an OA citation advantage, and OA did not increase the number of citations papers or chapters received from authors in developing countries.

Functional cellulose substrates with tetrazole moieties are generated to serve as universal platforms for the spatio-temporal immobilization of synthetic ultra-low fouling polymer brushes and protein species via a nitrile imine-mediated tetrazole-ene cycloaddition (NITEC)-based protocol. Poly(carboxybetaine acrylamide) brushes are grafted from initiators photo-patterned by NITEC utilizing single electron transfer living radical polymerization. Streptavidin is photo-immobilized with remarkable efficiency, opening the possibility to generate new materials for biomedical and biosensing applications.

We model the market for news as a two-sided market where newspapers sell news to readers who value accuracy and sell space to advertisers who value advert-receptive readers. In this setting, monopolistic newspapers under-report or bias news that sufficiently reduces advertiser profits. Paradoxically, increasing the size of advertising eventually leads competing newspapers to reduce advertiser bias. Nonetheless, advertisers can counter this effect if able to commit to news-sensitive cut-off strategies, potentially inducing as much bias as in the monopoly case. We use these results to explain contrasting historical and recent evidence on commercial bias and influence in the media.