Paper Session III-D - The Environmental Impact of Space Shuttle Exhaust, Year Three

The launch of the Space Shuttle creates two large exhaust plumes. They are commonly called the ground cloud, or ground plumes. One plume is created by the Space Shuttle Main Engines (SSMEs). The SSMEs are powered by liquid hydrogen and liquid oxygen so the ground cloud created by the SSMEs is basically a large steam cloud which does not have a very big impact on the plants. The other plume, the one my study focuses on is produced by the twin Solid Rocket Boosters (SRBs). This plume has the potential for much more environmental damage than the other

Lone Female Headship and Welfare Policy in Canada

The principal qualifying condition for welfare in Canada, unlike the US, is financial need - there are no demographic criteria. We use a time-series of annual, national cross-sections for the period 1981 through 1993 to estimate a model of lone-female headship. Our findings do not support the hypothesis that welfare benefit levels for one-parent and two-parent families are important determinants of the likelihood that a Canadian woman is a lone mother. In all models with provincial fixed effects, the coefficients for welfare benefits are small, statistically insignificant and often of the unexpected sign. We do find that the probability that a woman is a lone mother is generally associated in the expected fashion with her earnings capacity and the earnings capacity of her potential male partner, and with her age and schooling.

Do asymptomatic adults need screening EKGs?

Although certain electrocardiogram (EKG) findings in asymptomatic adults are associated with increased mortality (strength of recommendation [SOR]: A, high-quality cohort studies), no randomized trials demonstrate that any intervention based on abnormal screening EKGs improves outcomes in this group of patients. Comparison to a baseline EKG has a minimal effect on emergency department (ED) management. (SOR: B, 2 prospective studies and one retrospective study)

Overview of Standards for Technological and Engineering Literacy (Other)

In 2020, the International Technology and Engineering Educators Association (ITEEA) published Standards for Technological and Engineering Literacy: The Role of Technology and Engineering in STEM Education (STEL) [1]. These standards open with a clear rationale why all Pk-12 students should study technology and engineering: Technology and engineering are pervasive in all aspects of our lives. Every human activity is dependent upon the products, systems, and processes created to help grow food, provide shelter, communicate, work, and recreate. As the world grows more complex, it is increasingly important for everyone to understand more about technology and engineering [1, p. 1]. The goal of STEL is not to turn Pk-12 students into technologists or engineers—although many students may end up pursuing these career paths—rather STEL was created to broaden all student’s technological and engineering literacy so they can make informed decisions about the technologies they encounter in the world around them, and better contribute to their design, development, and use. This paper will provide a brief history of Pk-12 technology and engineering standards in the United States, an overview of STEL [1], and recommendations for STEL implementation

3D simulation of ammonia combustion in a lean premixed swirl burner

To date, a number of mechanical, electrical, thermal, and chemical approaches have been developed for storing electrical energy for utility-scale services. The only sufficiently flexible mechanism allowing large quantities of energy to be stored over long time periods is chemical energy storage in the form of carbon or hydrogen. One chemical considered for hydrogen carriage that can potentially be employed for storage is ammonia. Ammonia can substitute pure hydrogen for storage and be employed for power generation at large industrial scale if the molecule is efficiently burned through mature equipment such as gas turbines, thus providing not only a carbon free fuel, but also a chemical capable of being stored at low energy requirements. Thus, progress on the use of ammonia in gas turbines is a main priority for groups working on the area. Studies need to be conducted in experimental rigs with strong CFD analyses for further industrial implementation. In this paper, modelling of ammonia combustion in a generic gas turbine combustor is explored in order to provide an effective tool for future application. Large Eddy Simulation approach was used to develop a model for ammonia/hydrogen combustion in gas turbine combustors. To capture more details of the turbulent reacting flow, a detailed chemical mechanism was selected for a deep insight. A Partially Stirred Reactor framework was utilized to deal with the turbulence/chemistry interaction. The developed model was then applied to the simulation of lean premixed ammonia/hydrogen flames in a generic swirl burner. A preliminary validation for the model is performed by correlation of NOx emission with experimental data. Results show the model can provide detailed information of flow field, flame structure, emissions, etc. It can be used to optimize the procedure of utilizing ammonia as a fuel in future equipment design

A study on reduced chemical mechanisms of ammonia/methane combustion under gas turbine conditions

As an alternative fuel and hydrogen carrier, ammonia is believed to have good potential for future power generation. To explore the feasibility of co-firing ammonia with methane, studies involving robust numerical analyses with detailed chemistry are required to progress towards industrial implementation. Therefore, the objective of this study is to determine a reduced mechanism for simulation studies of ammonia/methane combustion in practical gas turbine combustor conditions. Firstly, five different sized reduced mechanisms of the well-known Konnov’s mechanism were compared. The reduced mechanisms were tested for ignition delay time validation (0D) using ammonia/methane mixtures at high pressure conditions relevant to gas turbine devices. Furthermore, the combustion products of ammonia/methane premixed laminar flames (1D) were validated with the results from the full Konnov’s mechanism. Finally, CFD simulations of a turbulent flame (2D) with all the reduced mechanisms were performed under high temperature and high pressure conditions representative of industrial systems. Results show that several of the reduced mechanisms utilized performed reasonably well in combustion simulation studies under gas turbine conditions. Hence a reaction mechanism with 48 species and 500 elementary reactions is recommended for future studies

Medical Physics Kickstart: designing a senior high school physics workshop.

A set of principles for the future design of senior high school physics workshops has been developed, with specific reference to medical physics. The principles address both specific challenges and misconceptions from the content, and general considerations related to the structure of the syllabus and therefore will provide a solid base for pedagogical design of workshops in other areas. Data were obtained from a variety of methods: Internet forum searches and focus groups with teachers and students were the main methods of research. The research indicated the key principles that need to be taken into consideration when designing the Medical Physics Kickstart session are: the four main syllabus problem areas of students, MRI, endoscope, ultrasound and diagnostic scans; the fact that many teachers do not have much experience in medical physics; and that teachers tend to teach the options last, after the core modules

Burnout, Depression, Anxiety, and Stress Among Resident Physicians 18 Months into the COVID-19 Pandemic: A Cross-Sectional Study

INTRODUCTION. Burnout among resident physicians has been an area of concern that predates the COVID-19 pandemic. With the significant turmoil during the pandemic, this study examined resident physicians’ burnout, depression, anxiety, and stress as well as the benefits of engaging in activities related to  wellness, mindfulness, or mental wellbeing. METHODS. The authors conducted a cross-sectional survey of 298 residents from 13 residency programs sponsored by the University of Kansas School of Medicine-Wichita, in October and November 2021. Authors used a 31-item questionnaire to measure levels of burnout, depression, anxiety, and stress. A mixed method approach was used to collect, analyze, and interpret the data. Descriptive statistics, One-way ANOVA/Kruskal-Wallis tests, adjusted odds ratios (aOR), and immersion-crystallization methods were used to analyze the data. RESULTS. There was a 52% response rate, with 65.8% (n=102) of the respondents reporting manifestations of burnout. Those who reported at least one manifestation of burnout experienced a higher level of emotional exhaustion (aOR=6.73; 95% CI, 2.66-16.99; P<.01), depression (aOR=1.21; 95% CI, 1.04-1.41; P=.01), anxiety (aOR=1.14; 95% CI, 1.00-1.30; P=.04), and stress (aOR=1.36; 95% CI, 1.13-1.64; P<.01). Some wellness activities respondents engaged in included regular physical activities, meditation and yoga, support from family and friends, religious activities, time away from work, and counseling sessions. CONCLUSIONS. The findings suggest the COVID-19 pandemic continues to pose a significant and worsening prevalence of burnout and other negative mental health effects on residents. Appropriate wellness and mental health support initiatives are needed to help resident physicians thrive in the health care environment

Revision more of the same, or is there greater merit in a different approach?

In the period prior to examinations students commonly spend hours revising, in an attempt to improve their knowledge and memory of the course work. This is certainly true in physics, hence research on the subject of revision could be deemed relevant and useful. In certain contexts there are two or more quite different approaches by which the material may be taught. The question arises: is it better, in terms of the understanding and retention of concepts, to revise the material using the same way it was initially taught, hoping to increase retention by repetition, or to use a different approach, hoping to improve understanding by parallel reinforcement? In the physics of elementary magneto-dynamics there is a "standard" approach to understanding why a current-carrying coil in a magnetic field experiences torque, in which the force on each side of a square loop is analysed separately. There is also a non-standard approach that considers the current-carrying loop to be a magnetic dipole between two magnetic poles, enabling students to predict whether or not torque is applied on a coil, and if so, the direction it would rotate. The teachers of 78 students in five classrooms trialled the non-standard approach. The control had 72 students in five classrooms revising the same syllabus material, their teachers re-using the traditional method. A pre-test was compiled based on a mixture of seven multiple-choice questions, together with free response questions from previous high school public examinations. The efficacy of the revision methods was assessed in four different ways. Initially the pre-test results were mapped against those of an identical post-test, and the improvement analysed. Later one of the free response questions was assessed using a five-level SOLO-style taxonomy. Qualitative data analysis also demonstrated where several participants were successfully using their revision method. Moreover, students assessed the novelty and perceived effectiveness of the revision method they employed using a selfrating questionnaire. The results were uniformly promising

Caveolin-1 in the regulation of cell metabolism: a cancer perspective

Caveolin-1 (CAV1) is an oncogenic membrane protein associated with endocytosis, extracellular matrix organisation, cholesterol distribution, cell migration and signaling. Recent studies reveal that CAV1 is involved in metabolic alterations – a critical strategy adopted by cancer cells to their survival advantage. Consequently, research findings suggest that CAV1, which is altered in several cancer types, influences tumour development or progression by controlling metabolism. Understanding the molecular interplay between CAV1 and metabolism could help uncover druggable metabolic targets or pathways of clinical relevance in cancer therapy. Here we review from a cancer perspective, the findings that CAV1 modulates cell metabolism with a focus on glycolysis, mitochondrial bioenergetics, glutaminolysis, fatty acid metabolism, and autophagy