Foot protein isoforms are expressed at different times during embryonic chick skeletal muscle development.

We have investigated the time course of expression of the alpha and beta triad junctional foot proteins in embryonic chick pectoral muscle. The level of [3H]ryanodine binding in muscle homogenates is low until day E20 of embryonic development, then increases dramatically at the time of hatching reaching adult levels by day N7 posthatch. The alpha and beta foot protein isoforms increase in abundance concomitantly with [3H]ryanodine binding. Using foot protein isoform-specific antibodies, the alpha foot protein is detected in a majority of fibers in day E10 muscle, while the beta isoform is first observed at low levels in a few fibers in day E15 muscle. A high molecular weight polypeptide, distinct from the alpha and beta proteins, is recognized by antifoot protein antibodies. This polypeptide is observed in day E8 muscle and declines in abundance with continued development. It appears to exist as a monomer and does not bind [3H]ryanodine. In contrast, the alpha isoform present in day E10 muscle and the beta isoform in day E20 muscle are oligomeric and bind [3H]ryanodine suggesting that they may exist as functional calcium channels in differentiating muscle. Comparison of the intracellular distributions of the alpha foot protein, f-actin, the heavy chain of myosin and titin in day E10 muscle indicates that the alpha foot protein is expressed during myofibril assembly and Z line formation. The differential expression of the foot protein isoforms in developing muscle, and their continued expression in mature muscle, is consistent with these proteins making different functional contributions. In addition, the expression of the alpha isoform during the time of organization of a differentiated muscle morphology suggests that foot proteins may participate in events involved in muscle differentiation

Dating with a Spinal Cord Injury: An IPA Study

Spinal Cord Injury (SCI) primarily affects young adults and approximately 52.3% of people are single at the time of injury (Spinal Cord Injury Facts, 2013). Several studies have revealed negative attitudes towards disabled individuals, particularly when asked to view them as a potential romantic partner (Chen, Brodwin, Cardoso & Chan, 2002; Rosenthal, Chen & Liveh, 2006; Hergenrather & Rhodes, 2007; Miller, Chen, Glover-Graf & Kranz, 2009; Marini, Chen, Feist, Flores-Torres & Del Castillo, 2011). Physical disability has also been found to interfere with establishing and maintaining romantic relationships (Howland & Rintala, 2001; Taleporos & McCabe, 2001a). While previous literature has explored the impact of an SCI on marriages and existing relationships, very little research has attempted to explore the challenges and limitations of being single and dating with an SCI. The paucity of literature concerning the experience of dating with an SCI is concerning, considering that approximately 50,000 people in the UK are currently living with this type of injury (Spinal Cord Injury Facts, 2013). This study aimed to explore the impact of dating with an SCI by asking six spinally injured women to describe their lived experience of dating post-injury. Data was collected using open-ended semi-structured interviews and were analysed using Interpretative Phenomenological Analysis (IPA). Participants’ experiences clustered into four superordinate themes: a) Dating as a Journey; b) Challenges to View of Self; c) Perceived Societal Attitudes and d) Dating Concerns. The empirical findings suggest that dating after spinal injury is complex and process orientated. Participants reported an initial grieving phase during which time dating was not a priority. As participants moved further through the process of coping, they were able to be more open to the prospect of dating. Participants also reported being affected by the negative expectations of others, including gender stereotypes. They also explored the issues of disclosure and control in relation to dating. These findings are discussed in relation to existing literature and research. In addition, aspects of the participants experienced are considered in terms of their practical use in creating workshops for newly injured spinally injured patients on topics such as body image, sexuality and dating. Implications for counselling psychology and for further research are explored

Classical percolation fingerprints in the high-temperature regime of the integer quantum Hall effect

We have performed magnetotransport experiments in the high-temperature regime (up to 50 K) of the integer quantum Hall effect for two-dimensional electron gases in semiconducting heterostructures. While the magnetic field dependence of the classical Hall law presents no anomaly at high temperatures, we find a breakdown of the Drude-Lorentz law for the longitudinal conductance beyond a crossover magnetic field B_c ~ 1 T, which turns out to be correlated with the onset of the integer quantum Hall effect at low temperatures. We show that the high magnetic field regime at B > B_c can be understood in terms of classical percolative transport in a smooth disordered potential. From the temperature dependence of the peak longitudinal conductance, we extract scaling exponents which are in good agreement with the theoretically expected values. We also prove that inelastic scattering on phonons is responsible for dissipation in a wide temperature range going from 1 to 50 K at high magnetic fields.Comment: 14 pages + 8 Figure

A dissipated energy comparison to evaluate fatigue resistance using 2PB

Flexural fatigue due to repeated traffic loading is a process of cumulative damage and one of the main failure modes of flexible pavement structures. Typically, micro-cracks originate at the bottom of an asphalt concrete layer due to horizontal tensile strains. Micro-cracking starts to propagate towards the upper layers under repeated loading which can lead to pavement failure. Different approaches are usually used to characterise fatigue resistance in asphalt mixtures including the phenomenological approach, the fracture mechanics approach and the dissipated energy approach. This paper presents a comparison of fatigue resistance calculated for different dissipated energy models using 2 Point Bending (2PB) at IFSTTAR in Nantes. 2PB tests have been undertaken under different loading and environmental conditions in order to evaluate the properties of the mixtures (stiffness, dissipated energy, fatigue life and healing effect)

Serial measurements of phosphorylated neurofilament-heavy in the serum of subjects with amyotrophic lateral sclerosis

There is a need for a blood biomarker of disease activity in ALS. This marker needs to measure the loss of motor neurones. Phosphorylated neurofilament heavy chain (pNfH) in the serum is a biomarker of axonal injury. Previous studies have found that levels of pNfH are elevated in ALS. We have performed a serial study of pNfH levels in 98 subjects from our ALS clinic. There was significant elevation of levels of pNfH in subjects with ALS compared to controls, although there was considerable variability. In studies of individuals who had two or more serial samples, we found that the levels of pNfH increased over time in the early stage of disease. Levels were low in subjects with long survival. The rate of rise of pNfH was inversely correlated with survival. We suggest that the initial level of pNfH is a marker of disease severity and that changes in pNfH levels are markers of disease progression

WATCHING THE SKY NEW REALIZATIONS, NEW MEANINGS, AND SURPRIZING ASPECTS IN UNIVERSITY LEVEL ASTRONOMY

Abstract: Learning astronomy is challenging at all levels due to the highly specialized form of communication used to share knowledge. When taking astronomy courses at different levels at university, learners are exposed to a variety of representations that are intended to help them learn about the structure and complexity of the Universe. However, not much is known about the reflective awareness that these representations evoke. Using a simulation video that provides a vivid virtual journey through our Milky Way galaxy, the nature of this awareness is captured and categorised for an array of learners (benchmark by results obtained for experts). The results illustrate how the number and nature of new things grounded in dimensionality, scale, time and perspective reflective awareness can too easily be taken for granted by both teachers and learners

Fatigue resistance: is it possible having a unique response?

The mechanical characterisation of the asphalt concrete in terms of both the fatigue resistance and the stiffness modulus is necessary to use any design method of the flexible road pavements. Different kinds of test are usually used in experimental work such as bending tests, uniaxial tests, etc., but sometimes they do not give the same answer. In this paper mechanical characterization was carried out by means of fatigue tests undertaken with two most used testing machines for asphalt material: two point bending (2PB) test at IFSTTAR in Nantes (France) and four point bending (4PB) test at University of Palermo, in Palermo (Italy). Different strain controlled tests were undertaken for the same material under the same loading conditions, frequency and temperature (15 Hz and 20˚C), according to the European standard 12697 part 24 and 26. The first results of this interlaboratory activity are showed in this paper

Variation in the cortical area map of C57BL/6J and DBA/2J inbred mice predicts strain identity

BACKGROUND: Recent discoveries suggest that arealization of the mammalian cortical sheet develops in a manner consonant with principles established for embryonic patterning of the body. Signaling centers release morphogens that determine regional growth and tissue identity by regulating regional expression of transcription factors. Research on mouse cortex has identified several candidate morphogens that affect anteroposterior or mediolateral cortical regionalization as well as mitogenesis. Inbred strains of laboratory mice can be exploited to study cortical area map formation if there are significant phenotypic differences with which to correlate gene polymorphism or expression data. Here we describe differences in the cortical area map of two commonly used inbred strains of laboratory mice, C57BL/6J and DBA/2J. Complete cortical hemispheres from adult mice were dissected and stained for the cytochrome oxidase enzyme in order to measure histochemically defined cortical areas. RESULTS: C57BL/6J has the larger neocortex, relatively larger primary visual cortex (V1), but relatively smaller posterior medial barrel subfield of the primary somatosensory cortex (PMBSF). The sample of C57BL/6J and DBA/2J mice can be discriminated with 90% accuracy on the basis of these three size dimensions. CONCLUSION: C57BL/6J and DBA/2J have markedly different cortical area maps, suggesting that inbred strains harbor enough phenotypic variation to encourage a forward genetic approach to understanding cortical development, complementing other approaches

Geometric morphometrics defines shape differences in the cortical area map of C57BL/6J and DBA/2J inbred mice

BACKGROUND: We previously described planar areal differences in adult mouse visual, somatosensory, and neocortex that collectively discriminated C57BL/6J and DBA/2J inbred strain identity. Here we use a novel application of established methods of two-dimensional geometric morphometrics to examine shape differences in the cortical area maps of these inbred strains. RESULTS: We used Procrustes superimposition to align a reliable set of landmarks in the plane of the cortical sheet from tangential sections stained for the cytochrome oxidase enzyme. Procrustes superimposition translates landmark configurations to a common origin, scales them to a common size, and rotates them to minimize an estimate of error. Remaining variation represents shape differences. We compared the variation in shape between C57BL/6J and DBA/2J relative to that within each strain using a permutation test of Goodall's F statistic. Significant differences in shape in the posterior medial barrel subfield (PMBSF), as well as differences in shape across primary sensory areas, characterize the cortical area maps of these common inbred, isogenic strains. CONCLUSION: C57BL/6J and DBA/2J have markedly different cortical area maps, in both size and shape. These differences suggest polymorphism in genetic factors underlying cortical specification, even between common isogenic strains. Comparing cortical phenotypes between normally varying inbred mice or between genetically modified mice can identify genetic contributions to cortical specification. Geometric morphometric analysis of shape represents an additional quantitative tool for the study of cortical development, regardless of whether it is studied from phenotype to gene or gene to phenotype