Data Report: carbonate concentrations of Paleogene sediment at Hole 1121B, Campbell Drift

Site 1121 is located southeast of New Zealand on the Campbell Drift (50°53.876´S 176°59.862´E) at a water depth of 4487.90 meters below sea level (mbsl). The site was drilled to recover an expanded sediment sequence from a Neogene contourite drift (Shipboard Scientific Party, 1999). Unexpectedly, the sequence between 32.7 and 132 meters below seafloor (mbsf) is composed of Paleogene siliceous and nannofossil-bearing ooze and chalk (Shipboard Scientific Party, 1999). This finding is intriguing because the location was probably fairly deep (>3800 mbsl) during the Paleogene (Shipboard Scientific Party, 1999), suggesting a carbonate compensation depth (CCD) significantly lower than expected from Cenozoic CCD curves (van Andel, 1975). Therefore, 39 samples of sediment were taken from Hole 1121B to construct a more detailed carbonate record of this interesting lithologic unit

Long-term landscape trajectory - Can we make predictions about landscape form and function for post-mining landforms?

A significant issue for the application of numerical Landscape Evolution Models (LEMs) is their calibration/parameterisation and validation. LEMs are now at the stage of development where if calibrated, they can provide meaningful and useful results. However, before use, each LEM requires a set of data and parameter values for it to run reliably and most importantly produce results with some measure of precision and accuracy. This calibration/validation process is largely carried out using parameter values determined from present day, or recent surface conditions which are themselves product of much longer-term geology-soil-climate-vegetation interactions. Here we examine the reliability of an LEM to predict catchment form over geological time (500,000 years) for a potential rehabilitated mine landform using defensible parameters derived from field plots. The findings demonstrate that there is no equifinality in landscape form with different parameter sets producing geomorphically and hydrologically unique landscapes throughout their entire evolution. This shows that parameterisation does matter over geological time scales. However, for shorter time scales (< 10,000 years) the geomorphic differences in hillslope form are minimal as described by the hypsometric curve, area–slope and cumulative area distribution, yet there are large differences in sediment output. Therefore, obtaining reliable and defensible parameters for input to LEMs is essential

Discrete cilia modelling with singularity distributions

We discuss in detail techniques for modelling flows due to finite and infinite arrays of beating cilia. An efficient technique, based on concepts from previous ‘singularity models’ is described, that is accurate in both near and far-fields. Cilia are modelled as curved slender ellipsoidal bodies by distributing Stokeslet and potential source dipole singularities along their centrelines, leading to an integral equation that can be solved using a simple and efficient discretisation. The computed velocity on the cilium surface is found to compare favourably with the boundary condition. We then present results for two topics of current interest in biology. 1) We present the first theoretical results showing the mechanism by which rotating embryonic nodal cilia produce a leftward flow by a ‘posterior tilt,’ and track particle motion in an array of three simulated nodal cilia. We find that, contrary to recent suggestions, there is no continuous layer of negative fluid transport close to the ciliated boundary. The mean leftward particle transport is found to be just over 1 μm/s, within experimentally measured ranges. We also discuss the accuracy of models that represent the action of cilia by steady rotlet arrays, in particular, confirming the importance of image systems in the boundary in establishing the far-field fluid transport. Future modelling may lead to understanding of the mechanisms by which morphogen gradients or mechanosensing cilia convert a directional flow to asymmetric gene expression. 2) We develop a more complex and detailed model of flow patterns in the periciliary layer of the airway surface liquid. Our results confirm that shear flow of the mucous layer drives a significant volume of periciliary liquid in the direction of mucus transport even during the recovery stroke of the cilia. Finally, we discuss the advantages and disadvantages of the singularity technique and outline future theoretical and experimental developments required to apply this technique to various other biological problems, particularly in the reproductive system

Developing and Validating a New Multi-Dimensional Scale for Anti-Social Behaviour in a Higher Education Setting

The purpose of this research is to construct and validate a multi-dimensional scale of Anti-social Behaviour (hereafter ASB) in a Western higher education context (i.e. USA). To achieve this, four studies, each with a different sample, were performed. Study 1 (n = 150) followed an exploratory design to generate a pool of potential items measuring ASB. Study 2 (n = 254) explored the dimensionality of the items produced in Study 1 using Exploratory Factor Analysis (EFA) and reliability measures. Study 3 (n = 654) confirmed the factorial structure from Study 2 and assessed the measurement model invariance using structural equation modelling (SEM). Finally, Study 4 (n = 287) assessed the predictive validity of the ASB measure through testing a hypothetical path model linking ASB to narcissism and Machiavellianism via an SEM procedure. In total, our research findings conclude that the ASB measurement model is a two-factor multi-dimensional structure comprising: Interpersonal Antagonistic Behaviour (six items) as well as Indirect Distractive Behaviour (four items). The research and practical implications for universities are thereafter discussed