Discrete molecular dynamics simulations of peptide aggregation

We study the aggregation of peptides using the discrete molecular dynamics simulations. At temperatures above the alpha-helix melting temperature of a single peptide, the model peptides aggregate into a multi-layer parallel beta-sheet structure. This structure has an inter-strand distance of 0.48 nm and an inter-sheet distance of 1.0 nm, which agree with experimental observations. In this model, the hydrogen bond interactions give rise to the inter-strand spacing in beta-sheets, while the Go interactions among side chains make beta-strands parallel to each other and allow beta-sheets to pack into layers. The aggregates also contain free edges which may allow for further aggregation of model peptides to form elongated fibrils.Comment: 15 pages, 8 figure

Nanoscale Mechanical Characterisation of Amyloid Fibrils Discovered in a Natural Adhesive

Using the atomic force microscope, we have investigated the nanoscale mechanical response of the attachment adhesive of the terrestrial alga Prasiola linearis (Prasiolales, Chlorophyta). We were able to locate and extend highly ordered mechanical structures directly from the natural adhesive matrix of the living plant. The in vivo mechanical response of the structured biopolymer often displayed the repetitive sawtooth force-extension characteristics of a material exhibiting high mechanical strength at the molecular level. Mechanical and histological evidence leads us to propose a mechanism for mechanical strength in our sample based on amyloid fibrils. These proteinaceous, pleated β-sheet complexes are usually associated with neurodegenerative diseases. However, we now conclude that the amyloid protein quaternary structures detected in our material should be considered as a possible generic mechanism for mechanical strength in natural adhesives

Mobile Graphic-based Communication: Investigating Reminder Notifications to Support Tuberculosis Treatment in Africa

Visual communication is a method of communication using visual elements, which is suggested to be more effective than text or voice, and has the additional advantage that it, can also be used by who are unable to read. In this paper, the findings of a user requirements study, which was conducted at MnaziMmoja Hospital in Zanzibar, are presented. In a cross-sectional study, twenty nine people including TB patients and TB Health care workers were interviewed. The findings show that participants agreed that the use of mobile graphic-based communications could support TB patients in their treatment. The contribution of this work is the process to investigate and develop a new mobile graphic-based application for push notification services that are literacy-level and language agnostic