We demonstrate that nanotubular networks formed by enzyme-triggered self-assembly of Fmoc-L3 (9-fluorenylmethoxycarbonyl-tri-leucine) show significant charge transport. FT-IR, fluorescence spectroscopy and wide angle X-ray scattering (WAXS) data confirm formation of beta-sheets that are locked together viapi-stacking interactions. Molecular dynamics simulations confirmed the pi-pi stacking distance between fluorenyl groups to be 3.6-3.8 A. Impedance spectroscopy demonstrated that the nanotubular xerogel networks possess minimum sheet resistances of 0.1 MOmega/sq in air and 500 MOmega/sq in vacuum (pressure: 1.03 mbar) at room temperature, with the conductivity scaling linearly with the mass of peptide in the network. These materials may provide a platform to interface biological components with electronics.

Peptide based 2D nanostructures of micronscale size in both X and Y dimensions are extremely rare because amino acid chirality favours helical structures, and nucleation-growth mechanisms usually favour uni-directional growth. We demonstrate the production of extended two-dimensional (2D) peptide nanostructures via the thermolysin catalysed condensation of Fmoc protected hydrophilic amino acid (serine, Fmoc-S) and a hydrophobic amino acid ester (phenylalanine, F-OMe). We propose that lateral self-assembly is enabled by the reversible nature of the system, favouring the thermodynamic product (extended sheets) over kinetically favoured 1 dimensional structures. Fmoc-SF-OMe forms extended arrays of β-sheet structures interlock via π-stacking between Fmoc groups. We propose that, due to its alternating hydrophilic/hydrophobic amino acid sequence, amphiphilic sheets presenting either phenyl or hydroxyl functionality are formed that assemble pair-wise, thereby shielding hydrophobic groups from the aqueous environment. Formation of these structures was supported by fluorescence emission spectroscopy, FTIR and XRD analysis and molecular mechanics minimization. At enhanced enzyme concentrations, hierarchical self-assembly was observed giving rise to spherulitic structures, with the number of spherulites dictated by enzyme concentration

Developing a course for online instruction requires content knowledge and understanding of the interactivity, technological requirements, and possibilities in the asynchronous environment. Using a case study method, the researchers investigated the development of an online humanities course by a team of faculty and instructional designers. Data were collected through observation of face-to-face planning meetings, document analysis of group postings at the online site, and interviews with the team members. Using Berge's typology of online facilitator roles and Stark and Luttuca's framework on academic plans, this study examined the roles assumed by team members and the curricular decisions.Distance education has emerged as an increasingly important component of higher education. A report by the National Center for Educational Statistics (1999) showed that a total of 1,680 institutions offered 54,000 college-level, credit-bearing distance education courses to 1.6 million distance students in 1997-1998. In the next 3 years, the number of institutions offering distance education grew by 38%; and more than half (56%) of all 2-year and 4-year degree granting institutions were involved in distance education. Over the same period, the number of students rose to more than three million participants in distance learning in all two-year and four-year institutions, a jump of 85% during the 3-year period (National Center for Educational Statistics, 2003). Although concrete data are not available, estimates suggest that most colleges and universities currently offer one or more courses online.

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