A demonstration of an affinity between pyrite and organic matter in a hydrothermal setting

One of the key-principles of the iron-sulphur world theory is to bring organic molecules close enough to interact with each other, using the surface of pyrite as a substrate in a hydrothermal setting. The present paper explores the relationship of pyrite and organic matter in a hydrothermal setting from the geological record; in hydrothermal calcite veins from Carboniferous limestones in central Ireland. Here, the organic matter is accumulated as coatings around, and through, pyrite grains. Most of the pyrite grains are euhedral-subhedral crystals, ranging in size from ca 0.1-0.5 mm in diameter, and they are scattered throughout the matrix of the vein calcite. The organic matter was deposited from a hydrothermal fluid at a temperature of at least 200°C, and gives a Raman signature of disordered carbon. This study points to an example from a hydrothermal setting in the geological record, demonstrating that pyrite can have a high potential for the concentration and accumulation of organic materials

Discal attachments of the human temporomandibular joint

The document attached has been archived with permission from the Australian Dental Association (8th Jan 2007). An external link to the publisher’s copy is included.Background: Despite its clinical significance, the anatomy of the human temporomandibular joint (TMJ) and its relationship to the lateral pterygoid muscle remains poorly described and often misrepresented in standard texts. The aim of this study was to describe how the anterior and posterior attachments of the TMJ disc vary between lateral, central and medial regions of the joint. Methods: Ten left TMJs were removed en bloc from cadavers and serial sections were made at 3-4mm intervals. Observations were made to ascertain the anterior and posterior attachments of the disc and the joint structures were traced from standardized photographs. Results: Laterally, the capsule and lateral discal ligament merged prior to their attachment at the condylar pole. Medially, muscle fibres, capsule and the disc converged on the medial pole of the condyle. There was no evidence that fibres of the upper head of the lateral pterygoid muscle inserted directly into the disc. The upper head inserted into the condyle either directly at the pterygoid fovea or via a central tendon or indirectly via the capsule. Posteriorly, the superior part of the posterior attachment of the disc attached to the cartilaginous meatus and tympanic part of the temporal bone. The inferior part of the posterior attachment of the disc attached to the posterior surface of the condyle. In four joints, this attachment was folded beneath the posterior band of the disc, creating a wedge-shaped flap that ran medio-laterally. Conclusion: This study is in broad agreement with other anatomical TMJ studies but there are two main points of difference. Firstly, a true muscle insertion of the superior head of the lateral pterygoid muscle to the disc was not observed. Secondly, a wedge-shaped flap of retrodiscal tissue was identified between the condyle and the disc.JE Christo, S Bennett, TM Wilkinson and GC Townsen

A mutate-and-map protocol for inferring base pairs in structured RNA

Chemical mapping is a widespread technique for structural analysis of nucleic acids in which a molecule's reactivity to different probes is quantified at single-nucleotide resolution and used to constrain structural modeling. This experimental framework has been extensively revisited in the past decade with new strategies for high-throughput read-outs, chemical modification, and rapid data analysis. Recently, we have coupled the technique to high-throughput mutagenesis. Point mutations of a base-paired nucleotide can lead to exposure of not only that nucleotide but also its interaction partner. Carrying out the mutation and mapping for the entire system gives an experimental approximation of the molecules contact map. Here, we give our in-house protocol for this mutate-and-map strategy, based on 96-well capillary electrophoresis, and we provide practical tips on interpreting the data to infer nucleic acid structure.Comment: 22 pages, 5 figure

Using eye-tracking and click-stream data to design adaptive training of children's inhibitory control in a maths and science game

Computerised educational neuroscience interventions that train within-domain inhibitory control (IC) can improve children's coun- terintuitive reasoning. However, the HCI or adaptive design of such en- vironments often receive less attention. Eye-tracking and click data were used to compare four versions of an IC-training game in terms of their HCI design and potential for supporting adaptive feedback. Our results provide insights for developing an adaptive system to scaffold pupils' transition towards using IC in un-cued, self-regulated scenarios

Diffusion Tensor Imaging determines three-dimensional architecture of human cervix: a cross sectional study

Objective To determine the microarchitecture of the cervix using high-resolution diffusion tensor (DT) magnetic resonance imaging (MRI). Design Cross-sectional study. Setting Leeds, UK. Sample Women undergoing hysterectomy for benign pathology. Methods Ex-vivo DT-MRI measurements were obtained using a 9.4-T Bruker nuclear magnetic resonance (NMR) spectrometer on seven fixed human cervices obtained at hysterectomy. A deterministic fibre-tracking algorithm was used to indirectly visualise underlying fibre organisation. Inter-regional differences in tissue structure were sought using quantitative measurements of diffusion. Main outcome measure The identification of an occlusive structure in the region corresponding to the internal cervical os. Results Fibre tracking demonstrated two regions: an outer circular and inner longitudinal layer. The total circumferential tract volume (TV) was greatest in the proximal region of the cervix (TV: proximal, 271 ± 198 mm3; middle, 186 ± 119 mm3; distal, 38 ± 36 mm3). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) measurements were significantly different between regions in all samples (P < 0.0005), indicating greater tract density and organisation towards the internal os. Conclusion Fibre tracking infers a system of dense, well-defined, encircling fibres in the proximal region of the cervix, corresponding to the location of the internal os. These findings may provide evidence of specific anatomic microarchitecture within the cervix able to resist intrauterine forces associated with pregnancy

Network analysis of human muscle adaptation to aging and contraction.

This is the final version. Available from Impact Journals via the DOI in this record. Resistance exercise (RE) remains a primary approach for minimising aging muscle decline. Understanding muscle adaptation to individual contractile components of RE (eccentric, concentric) might optimise RE-based intervention strategies. Herein, we employed a network-driven pipeline to identify putative molecular drivers of muscle aging and contraction mode responses. RNA-sequencing data was generated from young (21±1 y) and older (70±1 y) human skeletal muscle before and following acute unilateral concentric and contralateral eccentric contractions. Application of weighted gene co-expression network analysis identified 33 distinct gene clusters ('modules') with an expression profile regulated by aging, contraction and/or linked to muscle strength. These included two contraction 'responsive' modules (related to 'cell adhesion' and 'transcription factor' processes) that also correlated with the magnitude of post-exercise muscle strength decline. Module searches for 'hub' genes and enriched transcription factor binding sites established a refined set of candidate module-regulatory molecules (536 hub genes and 60 transcription factors) as possible contributors to muscle aging and/or contraction responses. Thus, network-driven analysis can identify new molecular candidates of functional relevance to muscle aging and contraction mode adaptations.Wellcome Trust Institutional Strategic Support AwardBiotechnology and Biological Sciences Research Counci

Home-ownership as a social norm and positional good: subjective well-being evidence from panel data

Much attention has been devoted to examining the absolute benefits of home-ownership (e.g. security and autonomy). This paper by contrast is concerned with conceptualising and testing the relative benefits of homeownership; those benefits that depend on an individual’s status in society. Home-ownership has previously been analysed as a social norm, implying that the relative benefits (costs) associated with being an owner (renter) are positively related to relevant others’ home-ownership values. The theoretical contribution of this paper is to additionally conceptualise home-ownership as a positional good, implying that the status of both home-owners and renters is negatively related to relevant others’ home-ownership consumption. The empirical contribution of this paper is to quantitatively test for these relative benefits in terms of subjective well-being. We run fixed effects regressions on three waves of the British Household Panel Study. We find that i) a strengthening of relevant others’ home-ownership values is associated with increases (decreases) in the subjective well-being of home-owners (renters), and ii) an increase in relevant others’ home-ownership consumption decreases the life satisfaction of owners but has no effect for renters. Overall our findings suggest that i) the relative benefit of home-ownership are both statistically significant and of a meaningful magnitude, and ii) homeownership is likely to be both a social norm and a positional good. Without explicitly recognising these relative benefits, policymakers risk overestimating the contribution of home-ownership to societal well-being