Are Reinforced Concrete Girder Bridges More Economical Than Structural Steel Girder Bridges ? A South African Perspective

This study investigated the cost-effectiveness of steel girders compared with conventional reinforced concrete girders used in bridge construction in South Africa. The investigation considered an existing bridge which required widening as a result of increased traffic flow. The consulting engineers chose two 10 m reinforced concrete girders for the end spans, while two 22 m post-tensioned reinforced concrete girders were used for the central spans. To determine the cost-effectiveness of the consulting engineer’s choice, steel girders were designed for the 10 m and 22m beams based on the relevant South African design codes of practice. The analysis was conducted for both non-composite and composite action between the steel girders and the reinforced concrete bridge deck. Based on the design calculations, a cost comparison was performed. The investigation revealed that steel girders are an economically viable option when off-the-shelf steel sections up to 10m in length are considered. For the 10 m girders, a significant cost saving was achieved for both noncomposite and composite construction compared with reinforced concrete. However, for the 22m spans, the post-tensioned reinforced concrete girders are significantly more cost-effective compared with steel plate girders. Thus, bridge design engineers should consider steel girders as an option during the conceptual design stage for end spans. A survey was also conducted among senior engineering professionals to determine the reason(s) for the apathy towards using structural steel sections as girders in bridge construction in South Africa

Unequal mass binary neutron star simulations with neutrino transport: Ejecta and neutrino emission

We present 12 new simulations of unequal mass neutron star mergers. The simulations are performed with the SpEC code, and utilize nuclear-theory-based equations of state and a two-moment gray neutrino transport scheme with an improved energy estimate based on evolving the number density. We model the neutron stars with the SFHo, LS220, and DD2 equations of state (EOS) and we study the neutrino and matter emission of all 12 models to search for robust trends between binary parameters and emission characteristics. We find that the total mass of the dynamical ejecta exceeds 0.01  M⊙ only for SFHo with weak dependence on the mass ratio across all models. We find that the ejecta have a broad electron fraction (Y_e) distribution (≈0.06–0.48), with mean 0.2. Y_e increases with neutrino irradiation over time, but decreases with increasing binary asymmetry. We also find that the models have ejecta with a broad asymptotic velocity distribution (≈0.05–0.7c). The average velocity lies in the range 0.2c−0.3c and decreases with binary asymmetry. Furthermore, we find that disk mass increases with binary asymmetry and stiffness of the EOS. The Y_e of the disk increases with softness of the EOS. The strongest neutrino emission occurs for the models with soft EOS. For (anti) electron neutrinos we find no significant dependence of the magnitude or angular distribution or neutrino luminosity with mass ratio. The heavier neutrino species have a luminosity dependence on mass ratio but an angular distribution which does not change with mass ratio

What Matters Most? An Exploration of Quality of Life Through the Everyday Experiences of Autistic Young People and Adults

BACKGROUND: The quality of life (QoL) of Autistic people is consistently reported to be poor compared with the general population. Little is known, however, about how Autistic people experience QoL from their perspectives and the ways they would like it to be enhanced. This qualitative study, conducted in collaboration with Autistic people, sought to understand how Autistic young people and adults define a good life and what helps and hinders them from achieving a good QoL. METHODS: We conducted semi-structured in-depth interviews with 34 Autistic adults and 14 Autistic adolescents about their everyday life experiences of different aspects of QoL, including physical health, sensory needs, mental health, money, home, transport, leisure, social connections, acceptance, and inclusion, being in charge of one's life and perceptions of the future. We coded transcripts in NVivo and analyzed them using reflexive thematic analysis. RESULTS: We identified four themes: two themes that described what a good QoL meant for our participants along with aspects of their lives that facilitated a good QoL: “feeling good” and “being myself in the world”; and two themes that described barriers to achieving a good QoL: “exhaustion and overwhelm” and “negative experiences shape perceptions.” DISCUSSION: These findings highlight the need to consider Autistic people's QoL within the context of their everyday realities. Enhancing QoL will only be achieved through focusing on these realities and through the provision of adaptations and supports to create more inclusive environments

Unequal mass binary neutron star simulations with neutrino transport: Ejecta and neutrino emission

We present 12 new simulations of unequal mass neutron star mergers. The simulations are performed with the SpEC code, and utilize nuclear-theory-based equations of state and a two-moment gray neutrino transport scheme with an improved energy estimate based on evolving the number density. We model the neutron stars with the SFHo, LS220, and DD2 equations of state (EOS) and we study the neutrino and matter emission of all 12 models to search for robust trends between binary parameters and emission characteristics. We find that the total mass of the dynamical ejecta exceeds 0.01  M⊙ only for SFHo with weak dependence on the mass ratio across all models. We find that the ejecta have a broad electron fraction (Y_e) distribution (≈0.06–0.48), with mean 0.2. Y_e increases with neutrino irradiation over time, but decreases with increasing binary asymmetry. We also find that the models have ejecta with a broad asymptotic velocity distribution (≈0.05–0.7c). The average velocity lies in the range 0.2c−0.3c and decreases with binary asymmetry. Furthermore, we find that disk mass increases with binary asymmetry and stiffness of the EOS. The Y_e of the disk increases with softness of the EOS. The strongest neutrino emission occurs for the models with soft EOS. For (anti) electron neutrinos we find no significant dependence of the magnitude or angular distribution or neutrino luminosity with mass ratio. The heavier neutrino species have a luminosity dependence on mass ratio but an angular distribution which does not change with mass ratio

Molecular Identity and Spatial Topography of Transient A-type Potassium Channels in the Rostral Nucleus of the Solitary Tract

The potent hedonic properties of tastes strongly affect dietary selection and are linked to clinical conditions associated with overconsumption and obesity. Understanding how taste is represented and processed in the brain is thus important to promote human health. CNS gustatory processing begins in the rostral nucleus of the solitary tract (rNST). Factors influencing the output signal from the rNST to areas that control ingestive behavior include the synaptic interactions of neurons within the nucleus and the intrinsic membrane properties of the neurons themselves. In particular, transient A-type potassium channels, which produce an outward IA current, have been shown to modulate sensory signals in both the caudal and rostral poles of the NST. However, the molecular identity of the IA channel on the two major phenotypes of neurons within the rNST, GABAergic interneurons and glutamatergic projection neurons, as well as the distribution of these channels within the different subdivisions of the rNST remains unclear. Previous literature suggest that IA is concentrated on non-GABAergic projection neurons in the central subdivision of rNST, while the channels are absent on GABAergic neurons in the ventral subdivision. However, we recently found that a subpopulation of GABAergic neurons do contain IA. Consequently, IA current is not exclusive to non-GABAergic projection cells, but exists on both cell phenotypes. In the present study, immunohistochemical and pharmacological approaches were used to identify the molecular identity of the potassium channel contributing to IA in the rNST and to describe its location within the nucleus. These data suggest that Kv4.3, a member of the Kv4 family, is primarily responsible for the IA current. Furthermore, it was observed that this channel is evenly distributed throughout the rNST, predominately in the neuropil, rather than on the cell soma. Pharmacologically blocking the IA channel using a toxin specific to the Kv4 family had similar effects on both GABAergic and non-GABAergic neurons. In both cell phenotypes the toxin reduced the first-spike delay and IA current amplitude seen in cells with IA. Because the expression of IA is sensitive to inhibition, we are exploring the interaction between IA and inhibition in sensory processing in the rNST.Research Supported by the NIH NIDCD Grant: ROIDC016112 Grant: R21DC013676Academic Major: Biolog

Comparative Genomics of Vancomycin-Resistant Staphylococcus aureus Strains and Their Positions within the Clade Most Commonly Associated with Methicillin-Resistant S. aureus Hospital-Acquired Infection in the United States

Methicillin-resistant Staphylococcus aureus (MRSA) strains are leading causes of hospital-acquired infections in the United States, and clonal cluster 5 (CC5) is the predominant lineage responsible for these infections. Since 2002, there have been 12 cases of vancomycin-resistant S. aureus (VRSA) infection in the United States—all CC5 strains. To understand this genetic background and what distinguishes it from other lineages, we generated and analyzed high-quality draft genome sequences for all available VRSA strains. Sequence comparisons show unambiguously that each strain independently acquired Tn1546 and that all VRSA strains last shared a common ancestor over 50 years ago, well before the occurrence of vancomycin resistance in this species. In contrast to existing hypotheses on what predisposes this lineage to acquire Tn1546, the barrier posed by restriction systems appears to be intact in most VRSA strains. However, VRSA (and other CC5) strains were found to possess a constellation of traits that appears to be optimized for proliferation in precisely the types of polymicrobic infection where transfer could occur. They lack a bacteriocin operon that would be predicted to limit the occurrence of non-CC5 strains in mixed infection and harbor a cluster of unique superantigens and lipoproteins to confound host immunity. A frameshift in dprA, which in other microbes influences uptake of foreign DNA, may also make this lineage conducive to foreign DNA acquisition

The role of social identity and self-efficacy in predicting service providers’ use of Stepping Stones Triple P following training

Background: Identifying factors that may contribute to the use of programs following the completion of training by practitioners is of practical and theoretical importance. Aim: This study examined the role of social identity and self-efficacy in contributing to the delivery of an evidence-based parenting program. Methods and Procedures: A sample of 63 multi-disciplinary professionals trained in the Stepping Stones Triple P-Positive Parenting Program, for parents of children with developmental disability, as part of a statewide roll-out were interviewed two years after training. Data on the number of hours of delivery during the 2-year period was analysed along with quantitative data obtained during interviews that assessed professionals’ self-efficacy and social identity as a Stepping Stones professional. Outcomes and Results: Social identity was associated with the use of SSTP in an independent analysis, but the association was no longer significant when other factors were included in a regression model. Self-efficacy predicted the use of SSTP and was found to be a mediator in the relationship between social identity and use of SSTP. Conclusions and Implications: This first investigation into the role of social identity in the implementation of evidence-based parenting programs showed that social identity could play an important role. The role of self-efficacy in predicting program use was further supported in this study and the mediator function of self-efficacy is explored. The practical and theoretical implications of the role of self-efficacy and social identity in the training of professionals are discussed.</p

Has management accounting research been critical?

This paper examines the contributions Management Accounting Research (MAR) has (and has not) made to social and critical analyses of management accounting in the twenty-five years since its launch. It commences with a personalised account of the first named author’s experiences of behavioural, social and critical accounting in the twenty-five years before MAR appeared. This covers events in the UK, especially the Management Control Workshop, Management Accounting Research conferences at Aston, the Inter-disciplinary Perspectives on Accounting Conferences; key departments and professors; and elsewhere the formation of pan-European networks, and reflections on a years’ visit to the USA. Papers published by MAR are analysed according to year of publication, country of author and research site, research method, research subject (type of organization or subject studied), data analysis method, topic, and theory. This revealed, after initial domination by UK academics, increasing Continental European influence; increasing use of qualitative methods over a wide range of topics, especially new costing methods, control system design, change and implementation, public sector transformation, and more recently risk management and creativity. Theoretical approaches have been diverse, often multi-disciplinary, and have employed surprisingly few economic theories relative to behavioural and social theories. The research spans mainly large public and private sector organisations especially in Europe. Seven themes perceived as of interest to a social and critical theory analysis are evaluated, namely: the search for ‘Relevance Lost’ and new costing; management control, the environment and the search for ‘fits’; reconstituting the public sector; change and institutional theory; post-structural, constructivist and critical contributions; social and environmental accounting; and the changing geography of time and space between European and American research. The paper concludes by assessing the contributions of MAR against the aspirations of groups identified in the opening personal historiography, which have been largely met. MAR has made substantial contributions to social and critical accounting (broadly defined) but not in critical areas endeavouring to give greater voice and influence to marginalised sectors of society worldwide. Third Sector organisations, politics, civil society involvement, development and developing countries, labour, the public interest, political economy, and until recently social and environmental accounting have been neglected