Risk Owners & Risk Managers: Dealing with the complexity of feeding children with neurodevelopmental disability

This paper illustrates negotiations around risk between lay people and clinicians in relation to gastrostomy interventions for disabled children. These negotiations centre on differing interpretations of what constitutes risk in relation to the safety of oral feeding and a child's need for a feeding tube between parents, carers and clinical specialties. Drawing on Heyman's distinction between risk managers and risk owners, we show that not only do clinicians act as risk managers and parents and carers as risk owners, but that these distinctions often become blurred either because of the shifting dynamics of relations of care or because of the specificity of clinical practice. Parents become risk managers in relation to carers' roles, while clinicians become risk owners in relation to particular procedures which define their practice. This has implications for lay and expert interactions as well as professional accountability for those caring for children with complex medical conditions. Although not an empirical article, we draw on empirical work in the UK. We analyse both parental and professional constructions of risk based on observations of co-ordinating a clinical trial designed to evaluate the effectiveness of gastrostomy surgery. We also examine the diverse value systems used by different groups of professionals and lay carers which inform judgements about risk and feeding. We conclude by arguing that issues of risk in contemporary health care are not just examples of ‘manufactured uncertainty’ or of ‘negotiated power’ but constitute a dialectical relationship which breaks down the essentialist dualism of lay and professional constructions of risk

A Fredholm Determinant Representation in ASEP

In previous work the authors found integral formulas for probabilities in the asymmetric simple exclusion process (ASEP) on the integer lattice. The dynamics are uniquely determined once the initial state is specified. In this note we restrict our attention to the case of step initial condition with particles at the positive integers, and consider the distribution function for the m'th particle from the left. In the previous work an infinite series of multiple integrals was derived for this distribution. In this note we show that the series can be summed to give a single integral whose integrand involves a Fredholm determinant. We use this determinant representation to derive (non-rigorously, at this writing) a scaling limit.Comment: 12 Pages. Version 3 includes a scaling conjectur

Generating Non-Linear Interpolants by Semidefinite Programming

Interpolation-based techniques have been widely and successfully applied in the verification of hardware and software, e.g., in bounded-model check- ing, CEGAR, SMT, etc., whose hardest part is how to synthesize interpolants. Various work for discovering interpolants for propositional logic, quantifier-free fragments of first-order theories and their combinations have been proposed. However, little work focuses on discovering polynomial interpolants in the literature. In this paper, we provide an approach for constructing non-linear interpolants based on semidefinite programming, and show how to apply such results to the verification of programs by examples.Comment: 22 pages, 4 figure

Impact of post-transplantation maintenance therapy on health-related quality of life in patients with multiple myeloma: data from the Connect® MM Registry

Maintenance therapy after autologous stem cell transplantation (ASCT) is recommended for use in multiple myeloma (MM); however, more data are needed on its impact on health-related quality of life (HRQoL). Presented here is an analysis of HRQoL in a Connect MM registry cohort of patients who received ASCT ± maintenance therapy. The Connect MM Registry is one of the earliest and largest, active, observational, prospective US registry of patients with symptomatic newly diagnosed MM. Patients completed the Functional Assessment of Cancer Therapy-MM (FACT-MM) version 4, EuroQol-5D (EQ-5D) questionnaire, and Brief Pain Inventory (BPI) at study entry and quarterly thereafter until death or study discontinuation. Patients in three groups were analyzed: any maintenance therapy (n = 244), lenalidomide-only maintenance therapy (n = 169), and no maintenance therapy (n = 137); any maintenance and lenalidomide-only maintenance groups were not mutually exclusive. There were no significant differences in change from pre-ASCT baseline between any maintenance (P = 0.60) and lenalidomide-only maintenance (P = 0.72) versus no maintenance for the FACT-MM total score. There were also no significant differences in change from pre-ASCT baseline between any maintenance and lenalidomide-only maintenance versus no maintenance for EQ-5D overall index, BPI, FACT-MM Trial Outcomes Index, and myeloma subscale scores. In all three groups, FACT-MM, EQ-5D Index, and BPI scores improved after ASCT; FACT-MM and BPI scores deteriorated at disease progression. These data suggest that post-ASCT any maintenance or lenalidomide-only maintenance does not negatively impact patients' HRQoL. Additional research is needed to verify these findings

Mother knows best: Gastrostomy feeding in disabled children -- professional and parental discourses.

This thesis explores professional and parental discourses in relation to gastrostomy feeding technologies. Drawing on resources from feminist poststructuralism as a rationale for interpreting women's accounts, it examines how these ideas can lend themselves to the study of parenting and feeding. Current clinical and research arenas bring health care providers, children and their families to make decisions about children's feeding. A prevalent medical discourse in feeding disabled children revolves around mabiourishment and poor growth, prompting a perception of the need for a gastrostomy feeding tube. Interviews with 22 mothers, between 1998 and 2001, formed part of an externally funded evaluation of gastrostomy feeding which the author was employed to coordinate. The author presents a deconstruction of the research study to explore how researchers mediate between different clinical and research discourses, and analyses how the subsequent political and ethical issues impact on children and their families. Women's accounts are analysed as constructing tube feeding as an intervention that either transforms their child by rendering her as 'other', or transforms their way of relating to the child, represented through oral feeding. Tube feeding was also constructed as an infringement of the child's rights to be involved and participate in social arenas, also associated with oral feeding. Both parents and clinicians constructed feeding decisions in terms of the child's best interests but, informed by competing and contradictory discourses, arrived at different conclusions about children's care. Parental accounts are analysed in terms of complex cultural-political overdeterminations between discourses of mothering, children's rights and normative child development. This analysis suggests that the clinical focus on weight-gain may underestimate women's concerns and has implications for how services support families. Drawing on reflexive methodological debates, the author highlights the needs and responses of researchers and clinicians, and indicates how these could be better addressed

A comprehensive techno-economic and power quality analysis of a remote PV-diesel system in Australia

Presently, the world is considering the integration of small, medium and large-scale PV systems into both urban and remote rural electricity networks. This sees a transition towards a 100% renewable energy based electricity supply from the current conventional fossil fuel based electricity supply. Australia has a significant electricity generation potential from solar PV resources which also encourages the uptake of PV-battery hybrid systems. Australian utilities operating in the isolated and remote areas are now seriously considering the integration of solar PV systems as a long-term solution to reduce costs and facilitate sustainable electricity generation. This would also defer expensive grid extension to supply electricity to these dispersed remote communities. This study aims to model and optimise a remote Australian PV-diesel system incorporated with high levels of PV penetration and battery storage and investigate the system power quality issues. The study includes system component optimisation and techno-economic analysis which considers the outcomes regarding the cost of energy (AUD$/kWh), fuel savings potential and environmental impacts. Power quality issues have been explored by analysing the response of fast frequency-responsive (FFR) battery storage. The overall study has found that higher levels of PV penetration integrated with the current diesel operated system provides a comprehensive and efficient electricity supply and FFR Li-ion batteries can mitigate transient power quality issues and maintain system frequency within acceptable limits

NuSTAR unveils a Compton-thick type 2 quasar in MrK 34

We present Nuclear Spectroscopic Telescope Array (NuSTAR) 3-40 keV observations of the optically selected Type 2 quasar (QSO2) SDSS J1034+6001 or Mrk 34. The high-quality hard X-ray spectrum and archival XMM-Newton data can be fitted self-consistently with a reflection-dominated continuum and a strong Fe K? fluorescence line with equivalent width >1 keV. Prior X-ray spectral fitting below 10 keV showed the source to be consistent with being obscured by Compton-thin column densities of gas along the line of sight, despite evidence for much higher columns from multiwavelength data. NuSTAR now enables a direct measurement of this column and shows that N H lies in the Compton-thick (CT) regime. The new data also show a high intrinsic 2-10 keV luminosity of L 2-10 ~ 1044 erg s–1, in contrast to previous low-energy X-ray measurements where L 2-10 lesssim 1043 erg s–1 (i.e., X-ray selection below 10 keV does not pick up this source as an intrinsically luminous obscured quasar). Both the obscuring column and the intrinsic power are about an order of magnitude (or more) larger than inferred from pre-NuSTAR X-ray spectral fitting. Mrk 34 is thus a "gold standard" CT QSO2 and is the nearest non-merging system in this class, in contrast to the other local CT quasar NGC 6240, which is currently undergoing a major merger coupled with strong star formation. For typical X-ray bolometric correction factors, the accretion luminosity of Mrk 34 is high enough to potentially power the total infrared luminosity. X-ray spectral fitting also shows that thermal emission related to star formation is unlikely to drive the observed bright soft component below ~3 keV, favoring photoionization instead

Cracks in Martensite Plates as Hydrogen Traps in a Bearing Steel

It is demonstrated that a macroscopically homogeneous distribution of tiny cracks introduced into a martensitic bearing steel sample can provide powerful hydrogen traps. The phenomenon has been investigated through thermal desorption spectroscopy and hydrogen permeation measurements using both cracked and integral samples. The e↵ective hydrogen di↵usion coefficient through the cracked sample is found to be far less than in the uncracked one. Similarly, when samples are charged with hydrogen, and then subjected to thermal desorption analysis, the amount of hydrogen liberated from the cracked sample is smaller due to the trapping by the cracks. Theoretical analysis of the data shows that the traps due to cracks are so strong, that any hydrogen within the cracks can never in practice de-trap and cause harm by mechanisms that require the hydrogen to be mobile for the onset of embrittlement.W. Solano-Alvarez is very grateful for support from the Worshipful Company of Ironmongers, CONACyT, the Cambridge Overseas Trust, and the Roberto Rocca Education Programme.This is the accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s11661-014-2680-8

Is postnatal depression a distinct subtype of major depressive disorder? An exploratory study

Postnatal depression (PND) has an estimated prevalence of 6.5 to 12.9%. In addition to the direct consequences for women, PND also interferes with the maternal-infant interaction, contributing to long-term cognitive and emotional impairments in exposed offspring. It is unclear how PND differs from major depressive disorder (MDD) more generally, and if PND represents a distinct subtype of depression. We explored whether women with a history of PND have specific differences in brain activation associated with sex hormone changes during the late luteal phase of the menstrual cycle, compared to parous women with either a past history of MDD outside of the postnatal period, or an absent history of MDD (‘never depressed’). Thirty mothers (history of PND (n = 10), history of MDD (n = 10), and ‘never depressed’ (n = 10)) underwent blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) acquisition during an emotional faces task. Amygdala activity was analysed using a region of interest (small volume correction) approach. There was a significant reduction in BOLD response to positive emotional faces in the right amygdala in women with a history of PND compared to women with a history of MDD. A similar but non-significant trend was found in the left amygdala in women with a history of PND compared to ‘never depressed’ women. Our findings support the hypothesis that women with vulnerability to PND represent a distinct subgroup of women with a differential sensitivity to changes in sex hormones. Further, albeit highly tentative, they provide a putative biomarker that could assist in detection of women at-risk to PND