Movement of the human foot in 100 pain free individuals aged 18–45 : implications for understanding normal foot function

Background: Understanding motion in the normal healthy foot is a prerequisite for understanding the effects of pathology and thereafter setting targets for interventions. Quality foot kinematic data from healthy feet will also assist the development of high quality and research based clinical models of foot biomechanics. To address gaps in the current literature we aimed to describe 3D foot kinematics using a 5 segment foot model in a population of 100 pain free individuals. Methods: Kinematics of the leg, calcaneus, midfoot, medial and lateral forefoot and hallux were measured in 100 self reported healthy and pain free individuals during walking. Descriptive statistics were used to characterise foot movements. Contributions from different foot segments to the total motion in each plane were also derived to explore functional roles of different parts of the foot. Results: Foot segments demonstrated greatest motion in the sagittal plane, but large ranges of movement in all planes. All foot segments demonstrated movement throughout gait, though least motion was observed between the midfoot and calcaneus. There was inconsistent evidence of movement coupling between joints. There were clear differences in motion data compared to foot segment models reported in the literature. Conclusions: The data reveal the foot is a multiarticular structure, movements are complex, show incomplete evidence of coupling, and vary person to person. The data provide a useful reference data set against which future experimental data can be compared and may provide the basis for conceptual models of foot function based on data rather than anecdotal observations

Investigating the cause(s) of the Eucalyptus gomphocephala (Tuart) decline epidemic in Western Australian native forest.

Tuart is a magnificent woodland tree endemic to the Swan Coastal Plain of Western Australia, and is one of the few eucalypts that is adapted to calcareous soil profiles (1). Prior to European settlement there were more than 111,600 ha of tuart woodlands (2) but this has been reduced to 30,311 mostly as a result of clearing for urban development and agriculture (3). In the early 1990’s the decline of tuart woodlands in Yalgorup National Park (YNP), 1.5 hours south of Perth, became severe causing public awareness and concern. At present, the majority of the 13,000 hectares of this park is affected. A large research group was established in 2003 to investigate the cause(s) of this decline, conducting research on a range of abiotic and biotic factors, including water relations and hydrology, environmental correlates, fire and competition, mycorrhizae and nutrition, fungal pathogens and insect pests. The collaborative, integrated and adaptive approach to the research, and the latest findings of the group will be presented

Visualizing transient low-populated structures of RNA

The visualization of RNA conformational changes has provided fundamental insights into how regulatory RNAs carry out their biological functions. The RNA structural transitions that have been characterized to date involve long-lived species that can be captured by structure characterization techniques. Here, we report the Nuclear Magnetic Resonance visualization of RNA transitions towards invisible ‘excited states’ (ES), which exist in too little abundance (2–13%) and for too short periods of time (45–250 μs) to allow structural characterization by conventional techniques. Transitions towards ESs result in localized rearrangements in base-pairing that alter building block elements of RNA architecture, including helix-junction-helix motifs and apical loops. The ES can inhibit function by sequestering residues involved in recognition and signaling or promote ATP-independent strand exchange. Thus, RNAs do not adopt a single conformation, but rather exist in rapid equilibrium with alternative ESs, which can be stabilized by cellular cues to affect functional outcomes

Crystal structure of ribosomal protein L4 shows RNA-binding sites for ribosome incorporation and feedback control of the S10 operon

Ribosomal protein L4 resides near the peptidyl transferase center of the bacterial ribosome and may, together with rRNA and proteins L2 and L3, actively participate in the catalysis of peptide bond formation. Escherichia coli L4 is also an autogenous feedback regulator of transcription and translation of the 11 gene S10 operon. The crystal structure of L4 from Thermotoga maritima at 1.7 Å resolution shows the protein with an alternating α/β fold and a large disordered loop region. Two separate binding sites for RNA are discernible. The N–terminal site, responsible for binding to rRNA, consists of the disordered loop with flanking α–helices. The C–terminal site, a prime candidate for the interaction with the leader sequence of the S10 mRNA, involves two non-consecutive α–helices. The structure also suggests a C–terminal protein-binding interface, through which L4 could be interacting with protein components of the transcriptional and/or translational machineries