The (Re) adaptability of Research Methodologies in the Instructional Design & Technology Field

In its revolutionary piece, On The Origin of Species, Darwin (1859) provided compelling evidence for the existence of the natural selection process. He described how species interact with their environments to cause variations in traits. Just like the species that Darwin explored in his research, the methodologies used in investigations related to the instructional design and technology (IDT) field have (re)adapted. This (re)adaptability serves to help us better inquire and explore the landscape of formal and informal educational learning environments available today

Assessing Neuronal and Astrocyte Derived Exosomes From Individuals With Mild Traumatic Brain Injury for Markers of Neurodegeneration and Cytotoxic Activity.

Mild traumatic brain injury (mTBI) disproportionately affects military service members and is very difficult to diagnose. To-date, there is currently no blood-based, diagnostic biomarker for mTBI cases with persistent post concussive symptoms. To examine the potential of neuronally-derived (NDE) and astrocytic-derived (ADE) exosome cargo proteins as biomarkers of chronic mTBI in younger adults, we examined plasma exosomes from a prospective longitudinal study of combat-related risk and resilience, marine resiliency study II (MRSII). After return from a combat-deployment participants were interviewed to assess TBI exposure while on deployment. Plasma exosomes from military service members with mTBI (mean age, 21.7 years, n = 19, avg. days since injury 151), and age-matched, controls (deployed service members who did not endorse a deployment-related TBI or a pre-deployment history of TBI; mean age, 21.95 years, n = 20) were precipitated and enriched against a neuronal adhesion protein, L1-CAM, and an astrocyte marker, glutamine aspartate transporter (GLAST) using magnetic beads to immunocapture the proteins and subsequently selected by fluorescent activated cell sorting (FACS). Extracted protein cargo from NDE and ADE preparations were quantified for protein levels implicated in TBI neuropathology by standard ELISAs and on the ultra-sensitive single molecule assay (Simoa) platform. Plasma NDE and ADE levels of Aβ42 were significantly higher while plasma NDE and ADE levels of the postsynaptic protein, neurogranin (NRGN) were significantly lower in participants endorsing mTBI exposure compared to controls with no TBI history. Plasma NDE and ADE levels of Aβ40, total tau, and neurofilament light (NFL), P-T181-tau, P-S396-tau were either undetectable or not significantly different between the two groups. In an effort to understand the pathogenetic potential of NDE and ADE cargo proteins, neuron-like cultures were treated with NDE and ADE preparations from TBI and non-TBI groups. Lastly, we determined that plasma NDE but not ADE cargo proteins from mTBI samples were found to be toxic to neuron-like recipient cells in vitro. These data support the presence of markers of neurodegeneration in NDEs of mTBI and suggest that these NDEs can be used as tools to identify pathogenic mechanisms of TBI

ALERT Doctoral School 2012: advanced experimental techniques in geomechanics

The twenty-second session of the European Graduate School 2012 (called usually ALERT Doctoral School) entitled Advanced experimental techniques in geomechanics is organized by Cino Viggiani, Steve Hall and Enrique Romero.Postprint (published version

PKS 0537-441: extended [O II] emission and a binary QSO?

We present high-resolution imaging and low-resolution spectroscopy of the BL Lac object PKS 0537-441 (z = 0.893) and its environment. The observations were designed to clarify, whether the properties of PKS 0537-441 are affected by gravitational microlensing, or whether PKS 0537-441 and its environment act as a lensing system itself. Our observations show that neither case seems to be likely. We did not find a galaxy along the line-of-sight to the BL Lac as claimed previously, our spectroscopy shows that none of the four closest companion galaxies is at high redshift. Two of the four nearby companion galaxies to PKS 0537-441 are within 200 km/s of the systemic velocity of the BL Lac (z = 0.892 and 0.895, respectively). The third companion galaxy is at higher redshift (z = 0.947). The fourth companion galaxy shows evidence of Mg II absorption redwards of its systemic velocity and is perhaps a mini low ionization BAL QSO at z = 0.885. If the latter can be confirmed, PKS 0537-441 is the first BL Lacertae object being a member of a binary Quasar. We also detected extended [O II] emission in the off-nuclear spectrum of PKS 05371-441, which is most likely due to photoionization from the active nucleus. Alternatively, the extended [O II] emission is due to jet-cloud interaction with the counterjet of PKS 0537-441. Our clustering analysis indicates that PKS 0537-441 is located in a cluster environment as rich as Abell type 0-1. This is supported by the detection of four galaxies in the field with similar redshifts as the BL Lac (Delta z < 0.002). We found serendipitously even more galaxies at somewhat higher redshifts (z = 0.9-1). Thus, PKS0537-441 might be located in front of a galaxy cluster at somewhat higher redshift or even be part of a large-scale structure with an extension towards the BL Lac.Comment: 13 pages, 9 figures, accepted for publication in A&

Using microbes to recover rare earths with low environmental impact?

Using Microbes to recover Rare Earths with low environmental impact Barbara Palumbo Roe, Simon Gregory, Antoni Milodowski, Julia West, Joanna Wragg British Geological Survey, Nicker Hill, Nottingham NG12 5GG, UK Steve Banwart, Maria Romero González, Wei Huang, Emma Wharfe Kroto Research Institute, University of Sheffield, Sheffield S3 7HQ, UK John Harding, Colin Freeman, Shaun Hall Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK Microbes play an important role in the fate and transport of rare earth elements (REE) in relation to the REE exploitation life cycle. A step change in understanding is needed for key mobilisation, concentration and fractionation processes such as bioleaching, biosorption and biomineralisation and how they can 1) be harnessed to recover REE in situ from low grade ores or secondary deposits, and 2) be quantified for reactive transport in environmental risk assessment and management of mining operations. Heap/in-situ leaching methods are relatively low impact mining technologies, requiring less energy (for comminution) and in the case of in-situ leaching have a minimal footprint. Furthermore, biologically-assisted leaching and separation processes represent a more sustainable alternative to chemical processes. We discuss the microbial potential to accelerate dissolution of REEs from source minerals, and how the natural selectivity of mineral and microbial surfaces as ligands for adsorption and biomineralisation of REE dissolved species could be exploited in the recovery of REEs from fluids

Modelling ground vibrations induced by harmonic loads

A finite-element model combining the frequency domain thin-layer method with paraxial boundary conditions to simulate the semi-infinite extent of a soil medium is presented in this paper. The combined numerical model is used to deal with harmonic vibrations of surface rigid foundations on non-horizontal soil profiles. The model can deal with soil media over rigid bedrock or significant depths of half-space. Structured finite elements are used to mesh simple geometry soil domains, whereas unstructured triangular mesh grids are employed to deal with complex geometry problems. Dynamic responses of homogeneous as well as layered soil profiles are simulated and validated against analytical and approximate solutions. Finally, the model is used to deal with surface ground vibration reduction, in which it is first validated against published results and then followed by an example involving a bridge

Using Bayesian Networks and Machine Learning to Predict Computer Science Success

Bayesian Networks and Machine Learning techniques were evaluated and compared for predicting academic performance of Computer Science students at the University of Cape Town. Bayesian Networks performed similarly to other classification models. The causal links AQ1 inherent in Bayesian Networks allow for understanding of the contributing factors for academic success in this field. The most effective indicators of success in first-year ‘core’ courses in Computer Science included the student’s scores for Mathematics and Physics as well as their aptitude for learning and their work ethos. It was found that unsuccessful students could be identified with ≈91% accuracy. This could help to increase throughput as well as student wellbeing at university

On the dissipative non-minimal braneworld inflation

We study the effects of the non-minimal coupling on the dissipative dynamics of the warm inflation in a braneworld setup, where the inflaton field is non-minimally coupled to induced gravity on the warped DGP brane. We study with details the effects of the non-minimal coupling and dissipation on the inflationary dynamics on the normal DGP branch of this scenario in the high-dissipation and high-energy regime. We show that incorporation of the non-minimal coupling in this setup decreases the number of e-folds relative to the minimal case. We also compare our model parameters with recent observational data.Comment: 32 pages, 6 figures. arXiv admin note: substantial text overlap with arXiv:1001.044

Can the gamma-ray source 3EG J2033+4118 be produced by the stellar system Cyg OB2 No.5?

We discuss the possibility that the stellar system Cyg OB2 No.5 can be a gamma-ray source in the light of recent EGRET and radio data. This system is formed by an O7 Ia + Ofpe/WN9 contact binary. A third star, probably a B0 V star also associated with the system, is located at $\sim 1700$ AU from the primary. We estimate the expected gamma-ray luminosity from the colliding winds region, the terminal shock of the wind, and the unstable zone at the base of the wind, and conclude that, under very reasonable assumptions, Cyg OB2 No.5 can generate about a half of the gamma-ray flux detected from the positionally coincident source 3EG J2033+4118. We suggest, then, that other O stars belonging to the association, also placed within the 95 % probability EGRET location contour, could contribute to the observed gamma-ray flux.Comment: Accepted for publication in Astronomy and Astrophysic

Non-Minimal Warm Inflation and Perturbations on the Warped DGP Brane with Modified Induced Gravity

We construct a warm inflation model with inflaton field non-minimally coupled to induced gravity on a warped DGP brane. We incorporate possible modification of the induced gravity on the brane in the spirit of $f(R)$-gravity. We study cosmological perturbations in this setup. In the case of two field inflation such as warm inflation, usually entropy perturbations are generated. While it is expected that in the case of one field inflation these perturbations to be removed, we show that even in the absence of the radiation field, entropy perturbations are generated in our setup due to non-minimal coupling and modification of the induced gravity.Comment: 29 pages, 7 figures, Accepted by Gen. Rel Gravi