Investigation of gas porosity in laser melted gray iron

Gray iron is one of the most common, versatile materials used today in the manufacturing world because it is inexpensive, yet strong and durable. If certain deficiencies in iron, specifically corrosion and wear in some applications, could be cost-effectively eliminated, then expensive alloys or composite materials would not be needed for some applications. Existing technology to improve the hardness and wear performance of iron has shown mixed results. A new technology, laser processing, is currently under development and shows great promise. Porosity is an identifiable problem when laser processing iron. Porosity, in general, can be traced to several sources. Some of the possibilities are shrinkage, trapped gases, material evaporation, and chemical reactions producing gases. In the case of laser melted iron, one reaction in particular is of interest. The oxidation of carbon in air is theorized to be a primary contributor to the porosity. Therefore this study investigates this hypothesis in order to verify the effect of oxygen on laser processed iron. For a specific set of processing conditions, inert shielding gases (nitrogen and argon) are compared with air to investigate the environmental effects, in particular the presence of oxygen, on the porosity. In addition, if oxygen is a problem, the possibility of using a deoxidizer to reduce porosity is considered. Titanium is chosen to be coated onto the gray iron to investigate this hypothesis. The current study investigates surface re-melting and alloying with titanium on gray iron. The results are presented quantitatively and qualitatively through metallurgical evaluation, gas chromatography, x-ray diffraction, SEM analysis, and microprobe analysis

Fungal Diversity and Cellulytic Activity in the Historic Huts, Ross Island, Antarctica

The goal of this study was to undertake a microbial investigation of the Historic Huts areas on Ross Island, to gain knowledge of the fungal biodiversity and biochemical framework, focusing on the wood degrading potential of these fungi at both psychrophilic (cold) and mesophilic (moderate) temperatures. Eight hundred and forty nine samples were collected from three Heroic Era Historic Huts of Antarctica, from a variety of substrates but predominantly structural wood. The huts, Discovery Hut at Hut Point, Terra Nova Hut at Cape Evans and Nimrod Hut at Cape Royds, are located on Ross Island and were all assembled in the early 20th century by the Heroic Era explorers to house the expeditions, stores and animals. These wooden huts were abandoned when the expeditions left. The introduction of wood and other organic material to a pristine environment along with the creation of a microclimate within the harsh Antarctica environment created interesting sites for studying fungal diversity, wood decay and fungal cellulase enzymes in an extreme environment. Each hut can be classified as offering different conditions and circumstances for fungal propagules. Of the three huts, Terra Nova Hut is the only hut where there are visible fungal blooms within the hut and it, with Discovery Hut, had the greatest number of samples that contained fungi compared to Nimrod Hut which had the least. Discovery Hut, at less than 500 metres from the United States McMurdo Station, is the most visited by scientist and base staff and has been the most demonstrably affected by human impact of the three huts due to its closeness to the research stations on Ross Island To ensure a full understanding of the fungal diversity of the Historic Hut sites, a variety of sampling techniques were used along with a variety of culture media. Two thousand and seventy six isolates consisting of 1177 filamentous fungi and 899 single celled microorganisms (yeast and bacteria) were isolated; all these cultures were frozen and now form the University of Waikato Antarctic Culture Collection. Five genera dominated the fungal isolates that were identified and these were Cladosporium, Geomyces, Cadophora, Penicillium and Thelebolus. The fungal diversity of these Historic Huts' communities is low but the members present are metabolically active, consistent with other microbial communities in the Antarctic. The Historic Huts and surroundings contain a diverse array of provision in the way of wood and supplies, which provide nutrient sources for fungal growth. Endemic organisms present in the soil could have been enriched by using the introduced nutrient sources as primary and/or second metabolic substrates. In addition, fungi could have been introduced with the wooden huts and supplies when they were brought to Antarctica by the Heroic Era explorers, or introduced in the subsequent years with visitors and conservation work conducted at the sites. These introduced organisms, though, would have had to adapt to the change in climate and conditions posed by the Antarctic in order to survive and be subsequently isolated in this study. A screen for carboxymethylcellulase (CMCase) activity was done on a selection of the fungal isolates as the first step to understand the cellulytic potential of the Antarctica fungal community inhabiting the huts. One hundred and six fungal isolates from a total of 404, that were screened were deemed to be CMCase positive, 27 fungal isolates were chosen for further study including quantifying the activity of extracellular endo-1,4-β-glucanase at psychrophilic and mesophilic incubation temperatures. All but one isolate could produce endo-1,4-β-glucanase activity at 4 C and many produced more endo-1,4-β-glucanase activity at 4 C than at 15 C. Cadophora malorum 182, Cadophora malorum 242, Penicillium roquefortii 405, Penicillium roquefortii 408, Geomyces sp. 711, Geomyces sp. 824 and Cladosporium oxysporium 805 were selected for in-depth study of growth characteristics including growth temperature preferences, growth on a variety of cellulose substrates, water activity, and carbon sources, the latter done by using a commercially available microtitre plate containing 95 carbon sources. All seven of the fungal isolates were classified as psychrotolerant and produced, when cultured at either 4 C or at 15 C, cellulase, protease, amylase, xylanase, and pectinase and mannanase enzyme activities. The range of water activity that the Antarctic Penicillium roquefortii isolates could grow at was distinctive when compared with food Penicillium roquefortii isolates. The utilisation of different carbon sources showed that like many studies of Antarctica organism they have a diverse range of enzymatic activity, but interestingly the activity does not differ greatly with incubation temperature with most carbon sources being used or not used at both incubation temperatures tested. Although it took longer for the fungi to grow at the psychrophilic temperatures, the range of carbon sources they utilised was not reduced. The protein composition of the extracellular supernatants was visualised using various electrophoretic and staining techniques. The cellulase activity of the protein bands was visualised by cellulose-containing zymograms, which illustrated that the cellulase complex in all fungi tested was multi-enzyme and differed between species, isolates and temperatures of culturing. The cellulase activity of Cadophora malorum 182 was enriched by purification techniques including ion exchange chromatography and native preparative electrophoresis. The protein complex was not purified to homogeneity, but enriched for a mixture of proteins and the mixture was described as having the following properties; a temperature range of β-1,4-glucan cellobiohydrolase activity from 20 C to 80 C with the optimum activity seen at 60 C, β-1,4-glucan cellobiohydrolase activity that is stable at 4, 25 and 40 C for at least 24 hrs, lost at 50 C and 80 C within 24 hrs and 2 minutes respectively. Along with β-1,4-glucan cellobiohydrolase activity, the protein mixture contained Avicelase, CMCase, xylanase and mannanase activity. The thesis research showed that there was limited fungal diversity in the Historic Huts and artefacts (a total of five dominant genera were identified) but the fungi are actively growing and producing viable spores in the cold of Antarctica and producing the necessary enzymes for degradation of wood. Although the metabolism and growth rate is slower at psychrophilic temperatures, the fungal isolates studied as part of this thesis research could still function enzymatically at cold temperatures and this includes the degradation of wood as evidenced by in vitro wood decay studies examined by scanning electron microscopy where two isolates of one species demonstrated the ability to degrade wood. The cellulase complex of the investigated fungal isolate was multi-enzymed and although the components were not purified to homogeneity, an enriched mixture of proteins had enzyme activity and stability in a broad temperature range, and activity to a variety of cellulosic substrates. This thesis research adds to the knowledge of the fungal biodiversity in the Antarctic and increases the understanding of the biochemical framework, participating in relation to wood decay potential of these Antarctic fungal isolates

Subtle Realism and Occupational Therapy: an Alternative Approach to Knowledge Generation and Evaluation

Occupational therapists are increasingly engaging in research. As this occurs, important and challenging questions are being asked about the most appropriate research approaches to use. Strongly held perspectives of what best constitutes evidence often conflict with influential hierarchies of research. The British Journal of Occupational Therapy has, in recent years, published a variety of papers and letters that have presented and defended effectively the differing perspectives of research approaches. Each of these has presented challenges to occupational therapy research. This opinion piece supports a combinist approach to research. It presents and defends such an approach from a subtle realist perspective

Policy addressing suicidality in children and young people: a scoping review protocol

Introduction Suicide is one of the leading causes of death among children and young people globally and a major public health issue. Government policies determine how much recognised health issues are prioritised and set the context for investment, development and delivery of services. A review of policies concerning children and young people who are suicidal could shed light on the extent that this public health issue is prioritised and highlight examples of best practice in this area. There has never been a review to explore how policy worldwide addresses the specific needs of this vulnerable population. This review will map the key policy documents and identify their relevance to the review question: how does policy address the treatment and care of children and young people who experience suicidality? (international, national (UK) and local (Scotland)). Methodology Employing scoping review methodological guidance a systematic and transparent approach will be taken. Preliminary searches will facilitate the identification of MeSh terms, subject headings, individual database and platform nuances. A full search strategy will be created to search five databases: CINAHL, PsychInfo, Medline, Web of Science and Cochrane. Government and other key agency websites (eg, WHO, Unicef) will be searched to identify policy documents. The reference lists of identified documents will be checked. A second reviewer will independently screen and cross validate eligible studies for final inclusion. A data extraction template will then be used to extract key information. We will report our findings using narrative synthesis and tabulate findings, by agreed key components. Ethics and dissemination Ethical approval is not required to conduct a scoping review. We will disseminate the findings through a peer-reviewed publication and conference presentation

Policy addressing suicidality in children and young people: An international scoping review

Suicide is a global health policy priority. As many as 800,000 lives are lost to suicide annually, in what is arguably a preventable cause of death. The World Health Organisation’s Mental Health Action Plan 2013-20 sets a target of reducing suicide rates by 10% by 2020, with member states agreeing to work towards this outcome. However, public policies instituted at national level can vary in how they translate this target into practical support. Suicide is a leading cause of death among children and young people (CYP) worldwide, with an estimated 1 in 3 children in some countries having considered suicide in the past year. Despite acknowledgment that children and young people have different needs to adults, most suicide prevention and mental health strategies take a universal approach, in which the specific needs for children and young people risk becoming lost. As the WHO’s target date of 2020 approaches, this briefing paper summarises a global review of national policy documents, considering how they address the treatment and care needs of suicidal children and young people. In doing so, it highlights best practice for how policy can influence the resourcing of services, and identifies gaps in policy provision for this vulnerable population. The paper aims to support both the WHO and individual countries that wish to develop new, or refine existing policies that address suicidality in children and young people

Factors that constitute a good cognitive behavioural treatment manual: A Delphi study

Cognitive behavioural treatment manuals have increased in frequency, purpose and impact over the last 40 years. Despite numerous papers on the topic, few empirical studies regarding the constitution of treatment manuals have been conducted. A Delphi study examining the factors that constitute a good cognitive behavioural treatment manual is presented. This study generated a consensus of opinion of factors that therapists and researchers should consider when developing and appraising treatment manuals for cognitive behavioural interventions. Limitations of the study and the potential relevance of the research are discussed

“100 Years of University Nursing Education”: The Significance of a Baccalaureate Nursing Degree and Its Public Health Origins for Nursing Now

Abstract The 100-year milestone of university nursing education at the University of British Columbia (UBC) in 2019 offers a pause for reflection and inquiry. History assists us to illuminate current issues and debates in light of past events. An examination of the legacy of Ethel Johns and others who held the vision of why nursing education should enter the university in 1919 sheds light on its historical significance, then and now. The first Director, Ethel Johns, referred to the establishment of the University of British Columbia Department of Nursing and the degree program it offered as “the experiment” (Johns, 1936). Reflections on “the experiment” provides a standpoint to consider how this courageous and visionary leader might have viewed the way “the experiment” is faring within the 21st century landscape of Canadian university nursing education. This reflection on the history of university nursing education and its public health origins is all the more pressing in the World Health Organization (WHO) declared International Year of the Nurse and the Midwife and, unprecedented over the last century, the emergence of a global COVID-19 pandemic and related public health crisis. The initiation of university education in 1919 was in part spurred by the Influenza epidemic of 1918 amidst a realization of the need for a breadth and depth of nursing education in public health and leadership, which was argued to be best situated within the regular post-secondary education system. We contend that this reflection is once again needed in nursing education programs. We offer a critique of how the pandemic of 2020 can illuminate current shortcomings in the baccalaureate preparation of nurses. The present context of the pandemic might prompt efforts to ensure nursing capacity is sufficient to engage with a public health crisis and provide the leadership – needed now, as it was then. Résumé Les 100 ans de formation universitaire en sciences infirmières à la University of British Columbia (UBC) en 2019 ont permis un temps de pause pour une réflexion et une évaluation. L’histoire nous aide à éclairer les problèmes et les débats actuels à la lumière des évènements passés. Un examen de l’héritage d’Ethel Johns et d’autres qui ont partagé une vision de la raison pour laquelle la formation en sciences infirmières devrait être offerte à l’université en 1919 fait la lumière sur son importance historique passée et présente. La première directrice, Ethel Johns, fait référence à la création du département des sciences infirmières de la University of British Columbia et le programme alors offert comme étant « l’expérience » (Johns, 1936). Les réflexions sur « l’expérience » offrent un point de vue pour considérer comment cette chef de file courageuse et visionnaire pourrait avoir vu la façon dont « l’expérience » se porte dans le contexte de la formation en sciences infirmières dans les universités canadiennes au 21e siècle. Cette réflexion sur l’histoire de la formation universitaire en sciences infirmières et ses origines de santé publique est d’autant plus pressante depuis que l’Organisation mondiale de la Santé (OMS) a déclaré cette année comme l’Année internationale des sages-femmes et du personnel infirmier, et suite à l’émergence d’une pandémie mondiale de COVID-19 et la crise de santé publique qui y est liée. Le commencement de la formation universitaire en 1919 a été en partie stimulée par l’épidémie de grippe de 1918 et la constatation du besoin d’une formation en sciences infirmières en santé publique et leadership, dont le meilleur endroit a été déterminé comme étant dans le système régulier d’études supérieures. Nous maintenons que cette réflexion est nécessaire une fois de plus dans les programmes de formation en sciences infirmières. Nous offrons une critique de la façon dont la pandémie de 2020 peut éclaircir les lacunes actuelles dans la préparation des infirmières au baccalauréat. Le contexte actuel de la pandémie pourrait susciter des efforts pour s’assurer que la capacité des services infirmiers est suffisante pour gérer une crise de santé publique et offrir le leadership qui est maintenant nécessaire, comme il l’a été à cette époque

Measuring memory integration: A metric tapping memory representation ratherthan inference

Our ability to link related events could be supported either byconnecting their representations in memory, or by storing themseparately but integrating their content when later drawinginferences. Here, we adapted classic memory contingencyanalyses to develop and validate an integration index designedto tap stored representations. We conducted three pre-registered experiments adopting this metric. We found positiverecall dependency for associations experienced both within thesame and across different events. Compared to a conventionalinference test, we found that recall dependency was moresensitive to a manipulation of memory integration. Leveragingrecall dependency to investigate individual differencesrevealed that better memory for contextual detail wasassociated with faster inference judgments, consistent withhigh-fidelity representations of related memories—but only forpeople who tended to store memories separately. Ourapproach, thus, provides an important tool to illuminate howrelated events are represented in memory