Core histones isolated from normal and butyrate‐treated HeLa cells have been reconstituted into nucleosome cores in order to analyze the role of histone acetylation in enhancing transcription factor binding to recognition sites in nucleosomal DNA. Moderate stimulation of nucleosome binding was observed for the basic helix‐loop‐helix factor USF and the Zn cluster DNA binding domain factor GAL4‐AH using heterogeneously acetylated histones. However, by coupling novel immunoblotting techniques to a gel retardation assay, we observed that nucleosome cores containing the most highly acetylated forms of histone H4 have the highest affinity for these two transcription factors. Western analysis of gel‐purified USF‐nucleosome and GAL4‐AH‐nucleosome complexes demonstrated the predominant presence of acetylated histone H4 relative to acetylated histone H3. Immunoprecipitation of USF‐nucleosome complexes with anti‐USF antibodies also demonstrated that these complexes were enriched preferentially in acetylated histone H4. These data show that USF and GAL4‐AH preferentially interact with nucleosome cores containing highly acetylated histone H4. Acetylation of histone H4 thus appears to play a primary role in the structural changes that mediate enhanced binding of transcription factors to their recognition sites within nucleosomes.

The renaissance of Li-S battery technology is evidenced by the intensive R&D efforts in recent years. Although the theoretical capacity and energy of a Li-S battery is theoretically very high, the projected usable energy is expected to be no more than twice that of state-of-the-art Li-ion batteries, or 500 Wh/kg. The recent "sulfur fever" has certainly gathered new knowledge on sulfur chemistry and electrochemistry, electrolytes, lithium metal, and their interactions in this "new" system; however, a real advance toward a practical Li-S battery is still missing. One of the main reasons behind this is the sensitivity of Li-S batteries to the experimental testing parameters. Sophisticated nanostructures are usually employed, while the practicality of these nanomaterials for batteries is rarely discussed. The sulfur electrode, usually engineered in a thin-film configuration, further poses uncertainties in the knowledge transfer from the lab to industry. This review article briefly overviews the recent research progress on Li-S batteries, followed by a discussion of the Li-S battery system from the authors' own understandings collected from their past few years of research. The critical findings, the unresolved issues, and the scientific gap between lab research and industrial application are discussed. The future work in Li-S battery research is also explored to propel relevant research efforts toward industrial applications.

The George T. Harrell Health Sciences Library at Penn State College of Medicine began a fee-based systematic review service, a model for cost recovery, in October 2013. This article describes the library's experience in establishing, introducing, and promoting the new service, which follows the Institute of Medicine's recommended standards for performing systematic reviews. The goal is to share this information with librarians who are contemplating starting such a service.

Purpose -The purpose of this article is to discuss the need for librarians to be proactively involved in institutional decisions regarding repurposing or annexation of library space. As libraries transition from print to electronic delivery of journals, especially in STM intensive libraries, administration will begin to question the need to retain large runs of bound print journal volumes, especially in light of the ever-present space crunch faced by many institutions. Design/methodology/approach -The paper provides a viewpoint based on the experience of repurposing library space for alternative use. Findings -Librarians must be proactive when addressing library space issues. It is imperative that librarians are actively involved in defining the direction and future of the library rather than waiting for the decision to be made for them by their institution. Originality/value -The paper advocates the need to be proactive rather than reactive in planning for the future use of library space.