Theory of the adiabatic bubble

"May 10, 1952.""Reprinted from Proceedings of the Midwest Conference on Fluid Dynamics, 1950.

Managing Water Shortages in the Western Electricity Grids

British Columbia’s electricity grid is comprised primarily of hydroelectric generating assets. The ability to store water in reservoirs is a significant advantage for the province allowing it to import from Alberta when prices are favourable. Alberta, has a heavily fossil-fuel based electricity portfolio, but has seen substantial growth in its wind energy capacity. However this variable energy technology impacts the province’s grid operations. Wind energy is both variable and uncertainty. However, wind energy in Alberta can be stored via BC’s reservoir systems. In this paper, we examine the extent that drought impacts the both overall operating costs as well as the cost of reducing CO2 emissions. We model the Alberta and BC interconnected grids varying both the impact of the drought and the transmission capacity between the provinces. We determine that storing wind energy leads to an overall cost reduction and that emission costs are between $20 and$60 per tonne of CO2.Wind power, carbon costs, electrical grids, mathematical programming

Thermodynamic equilibrium calculations for combustion jets

"November 20, 1950.""This paper describes methods for calculating the ideal performance of super-sonic combustion jets such as may be used for rocket engines, jet engines, and combustion gas turbines. Methods are provided for calculating the exceptionally high values of thrust and power that can be developed by this type of combustion jet. The principle of thermodynamic equilibrium is employed to predict the changes of chemical composition taking place in the burning jet mixture. A complete numerical calculation is given for a high pressure rocket jet using a simple fuel mixture of hydrogen and oxygen."--Page 1

Heat transfer to water boiling under pressure

"May 1, 1951.""Reprinted from ASME Transactions May, 1948.""The film coefficient of heat transfer from a hot metal surface to a boiling liquid was estimated from experiments with an electrically heated wire submerged in the liquid. The heat-flow rate was given by the consumption of electric power. The temperature drop through the film was taken as the difference between the surface temperature of the wire and the mean temperature of the liquid. The surface temperature of the wire was estimated by a small thermocouple. The graph of film coefficient, as a function of temperature drop through the film, is called the "boiling" curve. As the temperature drop increased, the film coefficient first rose to a maximum, then fell to a minimum, from which it rose steadily as the temperature drop continued to increase. When water was boiled at atmospheric pressure, different heated metals gave different boiling curves, Preliminary data are given for nickel, tungsten, chromel A, and chromel C. When water was boiled at different elevated pressures, the same heated metal gave different boiling curves. The data are given for nickel and chromel at 0, 25, 50, 75, and 100 psig. Throughout these experiments the general form of the boiling curve remains the same."--Page 369

Experimental and Modelling Investigation of a Novel Tetrafunctional Initiator in Free Radical Polymerization

An experimental and modelling investigation of a tetrafunctional initiator designed for free radical polymerizations is presented. Multifunctional initiators are believed to provide two advantages over traditional monofunctional initiators. With a higher number of functional sites per molecule, they are able to increase polymer production while simultaneously maintaining or increasing polymer molecular weight. Examination of the literature indicates the majority of academic and industrial published studies have investigated difunctional initiators with most focusing on styrene. In this thesis, a tetrafunctional initiator, JWEB50, was systematically investigated for a variety of monomer systems in order to develop a better understanding of the behaviour of multifunctional initiators in free radical polymerizations. A kinetic study comparing the tetrafunctional initiator to a monofunctional counterpart, TBEC, demonstrated that the impact of a multifunctional initiator is dependent upon monomer type. Regardless of the homo- or copolymer system examined, it was observed that the tetrafunctional initiator could produce higher rates of polymerization due to the greater number of labile groups per initiator molecule. However, the influence of the tetrafunctional initiator on the polymer molecular weight was dictated by the polymerization characteristics of the system in question. In the case of styrene, the tetrafunctional initiator maintained similar molecular weights compared to the monofunctional initiator while for methyl methacrylate (MMA), switching from a mono- to a tetrafunctional initiator actually decreased the polymer molecular weight. Other monomers such as butyl acrylate and vinyl acetate and copolymers of MMA and styrene or alpha-methyl styrene were examined to study the effect of initiator functionality in free radical polymerizations. Subsequent to the kinetic investigation, polystyrene and poly(methyl methacrylate) samples produced with the tetrafunctional initiator were characterized in detail in order to examine the effects of initiator functionality on polymer properties. Samples generated with the monofunctional initiator were used for comparison purposes. Chromatographic and dilute solution methods were able to detect significant levels of branching in the polystyrene sample produced with JWEB50, while poly(methyl methacrylate) samples showed no evidence of branching. Rheological tests involving a combination of oscillatory and creep shear measurements were completed in order to detect differences between samples. The presence of branching using rheological techniques was clearly observed for both polystyrene and poly(methyl methacrylate) samples produced with the tetrafunctional initiator. In order to explain the experimental results observed in the kinetic and polymer properties studies, a reaction mechanism for polymerizations initiated with a tetrafunctional initiator was proposed and used in the development of a mathematical model. Reactions involving the fate/efficiency of functional groups are properly accounted for, while in the past this had been ignored by modelling work in the literature. Based on model predictions, di-radical concentrations were estimated to be several orders of magnitude smaller than mono-radical concentrations and their contribution in the reaction mechanism was found to be negligible. Modelling results also demonstrated that the concentration and chain length of various polymer structures (i. e. , linear, star or coupled stars) depend upon monomer type and reaction conditions

Summary report for PARKE pilot 'learn to love being with less'

Report on the workshop event to Dave Hockham: Executive summary. On 15th June 2022 a Practice as Research Knowledge Exchange (PARKE) Workshop was held at the Bathway Theatre to explore the question: “How can we learn to love being with less?” This project explored the UN Sustainability Development Goal 11: sustainable cities and communities using a somatic co-production approach which was based on movement to music combined with the chormmunity methodology (Loper 2000) involving movement, images, and words to express feelings and thoughts. 15 participants, specifically selected from a range of backgrounds and ages, took part in the workshop. Some of the participants were community group leaders, whom we intentionally invited so they could apply any learning for their own practice working with community members. The aim of the workshop was two-fold: 1. Participants explored the key question and were asked to reflect on what they can take home from the workshop to make changes in their own life (personal impact). 2. Participants were asked to provide feedback on participating in a co-creation workshop with an intergenerational and diverse group and what they could learn from this for their own current work or future work with community groups. Outcomes of the knowledge exchange (KE) workshop At the end of the workshop all participants reported to feel positive about the day and all stated they could take home from the day something ‘valuable’ (e.g. a new perspective or approach). However, one person, who is active in the sustainability movement openly questioned the value of a workshop like this in the face of a global climate crisis, yet he did agree on the workshop bringing value in questioning representations, active listening and by exploring different forms of expressions. Participants further reported on ideas on changes in their behaviour such as worrying less about technology (emails), but to experience life more physically, to pay more attention when listening and to incorporate different forms of expression when working with members of the community. The diversity of the group was perceived as a beneficial vehicle for participants to learn about new perspectives and to exchange more freely

Pollinating insects: what do they mean to people and why does it matter?

1. People value pollinating insects, and especially bees, in a wide range of different ways: as beautiful or fascinating creatures; as providers of goods; as objects of stewardship; as participants in a greater, interconnected whole – in which humans also participate; and as creatures with lives and characters. 2. An understanding of pollinators as creative connectors, sustaining and creating life by moving from plant to plant, is particularly powerful. Pollinators prompt people to think about nature as an interconnected whole, in which they too participate; and can unlock feelings of wonder, awe, groundedness, concern, responsibility, and nostalgia. 3. Social and cultural values provide a powerful resource for effective communications, a store of pre-existing meanings and associations that can be used to frame messages. Communications about pollinators would resonate more powerfully if they framed pollinators as creative connecters, emblematic of the interconnected and interdependent nature of ecosystems. By contrast, communications which focus on what pollinators do for us (e.g. pollination framed as an ‘ecosystem service’) are rational but unemotional. 4. Communications drawing on these insights should: • Highlight first and foremost the critical role played by pollinators as creative connectors in a greater, interconnected whole • Acknowledge our dependency on that greater interconnected whole, but also our responsibilities as participants in it • Be willing to embrace and use non-scientific language, ideas and tonalities in talking about both pollinators and the interconnected whole of which they are part, for example: o spiritual/religious language in evoking feelings of awe and wonder at the greater interconnected whole o evocations of an idealised, traditional way of life, and the possibilities of reconnecting in some small way o metaphorical characterisations of pollinators as spreading life and love • Recognise that we face choices about the environment not just as individuals, but as a society; that people see evidence of our society as a whole making the wrong choices; and that the actions of any body seeking to campaign about pollinators will speak as loudly, if not louder, than the messages it promotes • Emphasise – in messages, but also in developing the case for a campaign – the link between the holistic perspective, subjective wellbeing, and reconnection: o reconnection with nature: the consolation of knowing that one has a place in an enduring, greater whole, and a responsibility to play a positive role in that whole o reconnection with self: the experience of a moment of self-aware contemplation in contrast to the day-to-day stresses of life o reconnection with history: a sense of contact with an idealised traditional way of life 5. If developed effectively, such campaigns will contribute to many of the key actions in the National Pollinator Strategy, and in particular actions relating to “supporting pollinators across towns, cities and the countryside” (including encouraging the public to take action) and to “raising awareness of what pollinators need to survive and thrive”. 6. Because they prompt people to think about and respond emotionally to the interconnectedness of nature, pollinators framed as creative connectors could play an important role in communications seeking to increase awareness and change behaviour in relation to a much wider range of policies and approaches which relate to the connectedness of nature: for example, maintaining wider natural connectivity, protecting biodiversity, and ensuring environmental resilience through approaches such as those relating to the concept of landscape level conservation. As such, pollinators could play an important role in delivery of the 25-year plan for the environment, and in particular in efforts to increase public engagement. 7. Compared to other pollinating insects, bees occupy a central position in our culture. The ‘popular bee’ is not a real insect, but a product of a blurring of species, idealisation of the past, ignorance of the diversity of pollinators and, often, a shaky grasp on what pollination actually means. It is, however, a very meaningful and valued insect, and as such can serve as a flagship for communications in all of the above areas. 8. In terms of wider policy and decision-making, this research offers a potential model of how to create an evidence-based catalogue of social and cultural values. The development of such an evidence-based catalogue, using a mix of interpretative and participatory methods to explore how, and in what capacities, people can and do value objects of interest, should be an essential pre-requisite for robust valuation across a wide range of natural environment policy areas, but in practice is rarely undertaken. 9. Some types of social and cultural value can be captured through economic valuation: either through monetisation or through the inclusion of non-monetised criteria in multi-criteria analysis approaches. To do this, however, it is essential that data-gathering tools assess the right things: e.g. that willingness-to-pay questions frame the object of value in the right capacity and from the right perspective. 10. It may be more practical and/or appropriate to take account of some types of social and cultural value in policy and decision-making through other mechanisms, such as public consultation, political representation, or open policy-making. It may not be possible to monetise some kinds of value. In other cases, the effort involved in economic valuation may be disproportionate. If alternative mechanisms are not used, there is a risk that certain kinds of social and cultural value, or certain objects of value, are systematically overlooked. 11. Key levers to ensure that these alternative mechanisms are used effectively include: • Align policy frameworks – for example, set priorities and requirements in overarching national policies which ensure key social and cultural values or objects of value are taken into account. • Provide contexts – for example, create public consultation contexts in which certain kinds of value will be surfaced, or objects of value considered. • Improve processes – e.g. ensure consultation questions frame objects of value in ways that invite the articulate of key values. 12. An evidence-based catalogue of social and cultural values also provides a basis on which to anticipate risks and opportunities arising from changes in public opinion. Social and cultural values may be widely available within a society or culture but not, at any given moment, widely used. It is not always possible to predict how patterns of use will change in response to policies (e.g. forest privatisation, neonicotinoid pesticide policy); but an evidence-based understanding of underlying social and cultural values makes it possible to develop and explore scenarios of how they could change and develop responses accordingly

Alignment of Canada's COVID-19 policy response with barriers and facilitators for coping reported by caregivers of youth with developmental delays, disorders, and disabilities

Introduction: The UNICEF-WHO Global Report on Developmental Delays, Disorders, and Disabilities is an ongoing initiative aimed at increasing awareness, compiling data, providing guidance on strengthening health systems, and engaging country-level partners. Data from its caregiver survey assessing impacts of the COVID-19 pandemic showed that half of youths with developmental delays and disabilities (DDDs) and their caregivers struggled to cope, with a significant portion reporting a lack of supports and difficulty managing the worsening of the child's symptoms in isolation. Governments created service strategies supporting vulnerable groups. Little is known about the alignment between COVID-19 policies for persons with disabilities and their lived experiences. Contextualizing caregivers’ experiences can promote the development of tailored public supports for these families following a public health crisis. Methods: Online survey data were collected from June-July 2020, leading to a convenience sample of caregivers of youth with DDDs across Canada. Respondents answered two open-ended questions regarding challenges and coping strategies during the pandemic. We conducted a thematic analysis of responses using inductive coding on NVivo software. Overarching codes derived from the dataset were contextualized using an analysis of provincial policies published during the pandemic. Parallels with these policies supported the exploration of families’ and youths’ experiences during the same period. Results: Five hundred and seventy-six (N = 576) participants answered open-ended questions. Barriers to coping included family mental health issues, concerns about the youths’ regression, challenges in online schooling, limited play spaces, and managing physical health during quarantine. Environmental barriers encompassed deteriorating family finances, loss of public services, and a lack of accessible information and supports. In contrast, caregivers reported coping facilitators, such as family time, outdoor activities, and their child's resilience. Environmental facilitators included community resources, public financial supports, and access to telehealth services. Few COVID-19 policies effectively addressed caregiver-identified barriers, while some restrictions hindered access to facilitators. Conclusion: Prioritizing needs of families of youths with DDDs during public health emergencies can significantly impact their experiences and mental health. Enhancing financial benefits, providing telehealth services, and creating inclusive public play spaces are priority areas as we navigate the post-pandemic landscape

EEG functional connectivity in infants at elevated familial likelihood for autism spectrum disorder

Background Many studies have reported that autism spectrum disorder (ASD) is associated with atypical structural and functional connectivity. However, we know relatively little about the development of these differences in infancy. Methods We used a high-density electroencephalogram (EEG) dataset pooled from two independent infant sibling cohorts, to characterize such neurodevelopmental deviations during the first years of life. EEG was recorded at 6 and 12 months of age in infants at typical (N = 92) or elevated likelihood for ASD (N = 90), determined by the presence of an older sibling with ASD. We computed the functional connectivity between cortical sources of EEG during video watching using the corrected imaginary part of phase-locking values. Results Our main analysis found no significant association between functional connectivity and ASD, showing only significant effects for age, sex, age-sex interaction, and site. Given these null results, we performed an exploratory analysis and observed, at 12 months, a negative correlation between functional connectivity and ADOS calibrated severity scores for restrictive and repetitive behaviors (RRB). Limitations The small sample of ASD participants inherent to sibling studies limits diagnostic group comparisons. Also, results from our secondary exploratory analysis should be considered only as potential relationships to further explore, given their increased vulnerability to false positives. Conclusions These results are inconclusive concerning an association between EEG functional connectivity and ASD in infancy. Exploratory analyses provided preliminary support for a relationship between RRB and functional connectivity specifically, but these preliminary observations need corroboration on larger samples