Vibrational and electronic entropy of β-cerium and γ-cerium measured by inelastic neutron scattering

Time-of-flight (TOF) inelastic neutron-scattering spectra were measured on β-cerium (double hcp) and γ-cerium (fcc) near the phase-transition temperature. Phonon densities of states (DOS) and crystal-field levels were extracted from the TOF spectra. A softening of the phonon DOS occurs in the transition from β- to γ-cerium, accounting for an increase in vibrational entropy of ΔSvibγ-β=(0.09±0.05)kB/atom. The entropy calculated from the crystal-field levels and a fit to calorimetry data from the literature were significantly larger in β-cerium than in γ-cerium below room temperature, but the difference was found to be negligible at the experimental phase-transition temperature. A contribution to the specific heat from Kondo spin fluctuations was consistent with the quasielastic magnetic scattering, but the difference between phases was negligible. To be consistent with the latent heat of the β-γ transition, the increase in vibrational entropy at the phase transition may be accompanied by a decrease in electronic entropy not associated with the crystal-field splitting or spin fluctuations. At least three sources of entropy need to be considered for the β-γ transition in cerium

The Barometer of My Heart Visual Matrix Research and Evaluation project

This report is the outcome of an in-depth study of audience reception of an artwork which itself involved years of in-depth inquiry and prolonged collaboration between artist, Mark Storor, and consultant endocrinologist, Dr Leighton Seal. The work was produced by Anna Ledgard in association with Artsadmin and was supported by a Wellcome Trust Large Arts Award and the Arts Council England. The Barometer of My Heart is an exploration through visual art and performance of men’s experiences of erectile dysfunction and impotence. In the popular imagination there is often a simple equation between the two that belies their complexity and diversity. Depending on circumstance and perspective, erectile dysfunction may be perceived as an issue related primarily to health, to intimate sexual relationships to performance in other spheres of life, to male identities or to the condition of masculinity in late modernity. It follows that although erectile dysfunction and impotence are related, they are not co-extensive. The former can be thought of as a bio-medical condition that afflicts individual men and has a wide range of physical and psychological correlates. It may be a symptom of a serious underlying health condition that demands assessment and interventi on– the title of the work draws attention to erectile dysfunction as an early warning of developing heart disease. However impotence is also existential, psychosocial and societal in its ramifications. In the performative cultures of contemporary western societies it signifies powerlessness, loss of agency and a failure to play one’s part. As such it is a challenge for men and women alike. The Barometer of my Heart arose in part from the wall of public silence and private despair that surrounds these issues – only too often met with incomprehension and fear. In the absence of public health education, erectile dysfunction attracts negative projections that may or may not be internalised. Men may delay seeking help with potential deadly consequences1. Impotence can be regarded as something to be worked through with professional healthcare and supportive relationships or it may be experienced as a source of shame and a psychosocial catastrophe. What then are the conditions for compassionate understanding and an enlightened public conversation? The Barometer of My Heart uses visual, acoustic and digital media in a performance to communicate matters that all too often have been shrouded in secrecy. It does this through a process of artistic enactment and symbolization rather than representation – in other words it presents its audiences with forms for the inchoate and unspoken feelings that the subject arouses. The audiences in our study made use of these cultural forms, mingling them with personal life experiences. We expected that their engagement would be accompanied by anxiety, fear, desire and perhaps hope –and that the scenes of the show would create a ‘third space’ where unacknowledged and unrecognized emotions could find expression and emerge into consciousness, perhaps for the first time. We had reason to believe that interviews or focus groups, relying on participants’ verbal accounts of experience, would fail to capture this emergent process. For this reason we used a recently developed group based method – the visual matrix2 – that gives expression through imagery and affect to what is ‘known’ but as yet ‘unthought’.3 When we began this study the method had already been used to assess civic engagement with public art, but not in such an intimate and private area of experience.4 Whereas our primary aim has been to understand and account for audience engagement with The Barometer of My Heart, a secondary aim has been to determine whether the visual matrix is a suitable method to study an artwork that deals with a subject that is hard to think about, hard to speak of and very often hard to bear

Effects of incremented loads over preferred values on psychophysical and selected gait kinematic factor

This study investigated the effects of incremented loads greater than maximal acceptable loads on selected locomotor kinematic and psychophysical variables for four different hand-held load-carriage methods. Ten male and ten female subjects, between the ages of 18 and 30, participated in four experimental sessions. Data collection involved obtaining selected anthropometric, strength, maximal load and preferred load, gait kinematic, and psychophysical values. The anthropometric, strength and load capacity variables enabled absolute and morphology normalised sex-based comparisons to be made. The kinematic and psychophysical parameters were used to quantify any changes from two sets of baseline values,"unloaded" and "maximal acceptable load" values, when loads were increased and carrying methods changed. Statistical analysis revealed that males were taller, heavier and stronger than females (p<0.05). Males chose significantly greater maximal acceptable loads and absolute maximal loads than females when expressed in their absolute or relative terms. Preferred walking speeds were not significantly different for unloaded or loaded conditions, although males walked significantly faster in absolute terms (but not in relative terms) than females. Different load carrying methods and incremented loads brought. about significant changes to several of the kinematic parameters investigated. Finally, ratings of perceived exertion, as well as the number of exertion sites, were seen to increase significantly as load increased. These values were not, however, significantly affected by differences in load carriage method

Developing Collaborative & Social Arts Practice: The Heart of Glass Research Partnership 2014—2017

This is a report based on the first three years of the Heart of Glass programme. It presents findings from a qualitative evaluation. In response to the idea that Creative People and Places (CPP) is an action research project, findings have been fed back to the Heart of Glass team iteratively throughout the first three years. In this report, we draw together those findings, presenting a series of detailed case studies of commissioned projects, interviews with key stakeholders and Heart of Glass staff

A novel real-time system to monitor cell aggregation and trajectories in rotating wall vessel bioreactors

Journal of Biotechnology, 125(3): pp. 416-424.Rotating wall vessel bioreactors (RWVs) constitute dynamic suspension culture venues for tissue engineering. Quantitative real-time assessment of the kinetics of cell–cell aggregation in RWVs can yield mechanistic information about the initial steps leading to the assembly of individual cells into tissue-like constructs. In our imaging system, fluorescently labeled cells suspended in a HARV-type RWV were irradiated by a laser-beam. Emission was recorded by a camera mounted at 90° to the excitation plane. Using macro lenses, the system identified 5 μm particles from a 5 cm working distance, distinguished aggregated 20 μm microspheres from larger (45 and 90 μm) microspheres, and plotted local trajectories of microspheres and cells. Sizes of PC12 cells assessed by our system matched conventional measurements. We validated the system's ability to follow HepG2 and PC12 aggregation in real time over 24 h of RWV culture. Taken together, our system provides the means to measure and analyze in real time the processes that lead to the 3D tissue-like assembly of diverse cell types into spheroids. Future studies include development of intelligent feedback algorithms, allowing automatic control over RWV rotational speed required to maintain aggregating cells and nascent tissue in continual free fall

Diffuse reflectance spectroscopy-enhanced drill for bone boundary detection

Intramedullary nailing is a routine orthopedic procedure used for treating fractures of femoral or tibial shafts. A critical part of this procedure involves the drilling of pilot holes in both ends of the bone for the placement of the screws that will secure the IM rod to sections of the fractured bone. This step introduces a risk of soft tissue damage because the drill bit, if not stopped in time, can transverse the bone-tissue boundary into the overlying muscle, causing unnecessary injury and prolonging healing time due to periosteum damage. In this respect, detecting the bone-tissue boundary before break-through can reduce the risks and complications associated with intramedullary nailing. Hence, in the present study, a two-wavelength diffuse reflectance spectroscopy technique was integrated into a surgical drill to optically detect bone-tissue boundary and automatically trigger the drill to stop. Furthermore, Monte-Carlo simulations were used to estimate the maximum distance from within the bone at which the bone-tissue boundary could be detected using DRS. The simulation results estimated that the detection distance, termed the “look-ahead-distance” was ∼1.5 mm for 1.3 mm source-detector fiber separation. Experimental measurements with 1.3 mm source-detector fiber separation showed that the look-ahead-distance was in the order of 250 µm in experiments with set drill rate and in the range of 1 mm in experiments where the holes were drilled by hand. Despite this difference, the automated DRS enhanced drill successfully detected the approaching bone tissue boundary when tested on samples of bovine femur and muscle tissue