Mackenzie Glaser Honors Portfolio

Mackenzie Glaser\u27s honors portfolio captured in May 2021

Bereavement and marriage are associated with antibody response to influenza vaccination in the elderly

Stressful life events exposure including bereavement, an event commonly experienced by elderly people, social support, marital status and satisfaction were examined in relation to antibody response to the annual trivalent influenza vaccination in an elderly community sample (N = 184). Antibody response was assessed at baseline, and at one and 12 months following vaccination. Taking into account baseline antibody titer, overall life events exposure and social support were not associated with response to any of the influenza strains. However, bereavement in the year prior to vaccination was negatively associated with the one-month response to the A/Panama and B/Shangdong strains. Being married and having higher marital satisfaction was also associated with higher peak responses to the A/Panama influenza strain at one month. The positive association between marital satisfaction and A/Panama response was particularly evident in the younger half of the married sample. These associations largely withstood adjustment for potential confounders. Thus, in the elderly, peak antibody response was associated with bereavement and marriage, and not the more general factors, life events and social support, related to antibody response in student samples. This suggests the importance of taking a life course approach to examining relationships between psychosocial factors and immunity, and that interventions to modify the impact of these factors should address those most salient for each age group

Design to Delivery of Additively Manufactured Propulsion Systems for the SWARM-EX Mission

Recent progress in miniaturized spacecraft propulsion technology has allowed for the development of complex, multi-vehicle missions which enable the cost-effective realization of science goals that would previously have been prohibitively expensive. The upcoming NSF-funded Space Weather Atmospheric Reconfigurable Multiscale EXperiment (SWARM-EX) mission leverages these swarm techniques to demonstrate novel autonomous formation flying capabilities while characterizing the spatial and temporal variability of ion-neutral interactions in the Equatorial Ionization Anomaly and Equatorial Thermospheric Anomaly. SWARM-EX will fly a trio of 3U CubeSats in a variety of relative orbits with along-track separations ranging from 3 km to 1300 km. To achieve the required orbital variability, the mission uses a novel hybrid approach of differential drag and an onboard cold gas propulsion system. Mission requirements necessitate a propulsion system that provides each spacecraft with 15 m/s of ∆V and a maximum thrust greater than 5 mN in a volume of roughly 0.7U (7 cm x 10 cm x 10 cm). Unlike many other CubeSat-scale cold gas propulsion systems which are used to provide attitude control and perform reaction wheel desaturation burns, the primary objective of the SWARM-EX propulsion system (SEPS) is to provide ∆V during maneuvers. The Georgia Institute of Technology Space Systems Design Laboratory (SSDL) is conducting the design, assembly, and testing of three identical SEPS. By leveraging additive manufacturing technology, the propellant tanks, nozzle, and tubing are combined into a single structure that efficiently utilizes the allocated volume. The propulsion system uses two-phase R-236fa refrigerant as a propellant, which allows for the storage of the majority of propellant mass as a liquid to maximize volumetric efficiency. The final design allows for 17 m/s of total ∆V per spacecraft and a measured maximum thrust of approximately 35 mN for short pulse lengths at room temperature. Each individual propulsion system has a volume under 0.5U (489 cm3), making them among the smallest formation-flying CubeSat-scale propulsion systems developed thus far. Owing to their two-phase propellant storage and single nozzle, the SEPS have a high impulse density (total impulse provided per unit of system volume) of 176 N-s/L. Additionally, process improvements to mitigate known failure modes such as propellant leaks and foreign object debris are implemented. This paper describes the entire design-to-delivery life cycle of the SWARM-EX propulsion units, including pertinent mission requirements, propulsion system design methodologies, assembly, and testing. Major lessons learned for future small satellite propulsive endeavors are also detailed

Can programme theory be used as a 'translational tool’ to optimise health service delivery in a national early years’ initiative in Scotland: a case study

Background Theory-based evaluation (TBE) approaches are heralded as supporting formative evaluation by facilitating increased use of evaluative findings to guide programme improvement. It is essential that learning from programme implementation is better used to improve delivery and to inform other initiatives, if interventions are to be as effective as they have the potential to be. Nonetheless, few studies describe formative feedback methods, or report direct instrumental use of findings resulting from TBE. This paper uses the case of Scotland’s, National Health Service, early years’, oral health improvement initiative (Childsmile) to describe the use of TBE as a framework for providing feedback on delivery to programme staff and to assess its impact on programmatic action.<p></p> Methods In-depth, semi-structured interviews and focus groups with key stakeholders explored perceived deviations between the Childsmile programme 'as delivered’ and its Programme Theory (PT). The data was thematically analysed using constant comparative methods. Findings were shared with key programme stakeholders and discussions around likely impact and necessary actions were facilitated by the authors. Documentary review and ongoing observations of programme meetings were undertaken to assess the extent to which learning was acted upon.<p></p> Results On the whole, the activities documented in Childsmile’s PT were implemented as intended. This paper purposefully focuses on those activities where variation in delivery was evident. Differences resulted from the stage of roll-out reached and the flexibility given to individual NHS boards to tailor local implementation. Some adaptations were thought to have diverged from the central features of Childsmile’s PT, to the extent that there was a risk to achieving outcomes. The methods employed prompted national service improvement action, and proposals for local action by individual NHS boards to address this.<p></p> Conclusions The TBE approach provided a platform, to direct attention to areas of risk within a national health initiative, and to agree which intervention components were 'core’ to its hypothesised success. The study demonstrates that PT can be used as a 'translational tool’ to facilitate instrumental use of evaluative findings to optimise implementation within a complex health improvement programme.<p></p&gt

Strategies used as spectroscopy of financial markets reveal new stylized facts

We propose a new set of stylized facts quantifying the structure of financial markets. The key idea is to study the combined structure of both investment strategies and prices in order to open a qualitatively new level of understanding of financial and economic markets. We study the detailed order flow on the Shenzhen Stock Exchange of China for the whole year of 2003. This enormous dataset allows us to compare (i) a closed national market (A-shares) with an international market (B-shares), (ii) individuals and institutions and (iii) real investors to random strategies with respect to timing that share otherwise all other characteristics. We find that more trading results in smaller net return due to trading frictions. We unveiled quantitative power laws with non-trivial exponents, that quantify the deterioration of performance with frequency and with holding period of the strategies used by investors. Random strategies are found to perform much better than real ones, both for winners and losers. Surprising large arbitrage opportunities exist, especially when using zero-intelligence strategies. This is a diagnostic of possible inefficiencies of these financial markets.Comment: 13 pages including 5 figures and 1 tabl

Homeward bound or bound for a home? Assessing the capacity of dementia patients to make decisions about hospital discharge: Comparing practice with legal standards

Background This article stems from a larger project which considers ways of improving assessments of capacity and judgements about best interests in connection with people with dementia admitted to acute hospitals with respect to decisions about place of residence. Aims Our aim is to comment on how assessments of residence capacity are actually performed on general hospital wards compared with legal standards for the assessment of capacity set out in the Mental Capacity Act, 2005 (MCA). Method Our findings are grounded in ethnographic ward-based observations and in-depth interviews conducted in three hospital wards, in two hospitals (acute and rehabilitation), within two NHS healthcare trusts in the North of England over a period of nine months between 2008 and 2009. Twenty-nine patient cases were recruited to the study. We also draw from broader conceptions of capacity found in domestic and international legal, medical, ethical and social science literature. Results Our findings suggest that whilst professionals profess to be familiar with broad legal standards governing the assessment of capacity under the MCA, these standards are not routinely applied in practice in general hospital settings when assessing capacity to decide place of residence on discharge from hospital. We discuss whether the criteria set out in the MCA and the guidance in its Code of Practice are sufficient when assessing residence capacity, given the particular ambiguities and complexities of this capacity. Conclusions We conclude by suggesting that more specific legal standards are required when assessing capacity in this particular context

How do theories become self-fulfilling? Clarifying the process of Barnesian performativity

To explore when theories become self-fulfilling in our original paper (Marti & Gond, 2018), we first had to develop a process model of how theories become self-fulfilling. We argued that this process involves three steps: (1) new theories lead to experimentation, (2) experimentation produces anomalies, and (3) anomalies convince initially unconvinced actors to shift their practices. Our critics (i.e., D’Adderio, Glaser, & Pollock, 2019; Garud & Gehman, 2019; Shadnam, 2019) raise important issues about our process model, which is why we use this response to clarify our argument about the process of Barnesian performativity. In Section 1, we lay the groundwork for our response by explaining why Barnesian performativity is relevant to organization and management theory. In Section 2, we show that our model is in line with important insights from our critics: we show why self-fulfilling theories can be part of an “ongoing journey” (Garud & Gehman, 2019: 1), how anomalies can lead to new theories (D’Adderio et al., 2019), and why our model matters for folk theories (D’Adderio et al., 2019). In Section 3, we reflect on our process model from a philosophy of science perspective by discussing the role that “reality” plays in each step of our process model. We thereby address concerns that our process model is “positivist” (Shadnam, 2019: 1), “representational” (Garud & Gehman, 2019: 3), and “essentialist” (D’Adderio et al., 2019: 3)

Lessons Learned During the Implementation of a Cold Gas Propulsion System for the SunRISE Mission

The SunRISE mission utilizes a two-phase cold gas propulsion system, which provides several advantages over other cold gas systems but experienced challenges during assembly and testing. Since 2020, Georgia Tech Research Corporation (GTRC), Utah State University Space Dynamics Laboratory (SDL), and the Jet Propulsion Laboratory (FPL) have implemented several improvements to the SunRISE propulsion system. The SunRISE propulsion system leverages an additively manufactured monolithic structure, commercial off-the-shelf (COTS) valves and transducers, and the benign working fluid R-236fa to provide a suitable propulsion system for the SunRise mission. While the GTRC propulsion system had been developed for other missions, the multi-organizational team found and corrected several previously undetected design issues, including filters with highly variable flow performance, solenoid valve drive circuit issues, and inconsistencies in the tank additive manufacturing process that impacted manufacturing yield, thrust consistency, and quality of seals. Leaks in metallic fittings were also identified, and process improvements were put in place to mitigate them. Solenoid valve stiction was the last issue which was mitigated through valve screening and drive circuit adjustments. In this paper, we present lessons learned from the SunRISE propulsion system effort to aid future teams in identifying and addressing similar issues

Constructing Spaces for Strategic Work: A Multimodal Perspective

This paper takes seriously the call for strategy-as-practice research to address the material, spatial and bodily aspects of strategic work. Drawing on a video-ethnographic study of strategic episodes in a financial trading context, we develop a conceptual framework that elaborates on strategic work as socially accomplished within particular spaces that are constructed through different orchestrations of material, bodily and discursive resources. Building on the findings, our study identifies three types of strategic work, private work, collaborative work and negotiating work, that are accomplished within three distinct spaces that are constructed through multi-modal constellations of semiotic resources. We show that these spaces, and the activities performed within them, are continuously shifting in ways that enable and constrain the particular outcomes of a strategic episode. Our framework contributes to the strategy-as-practice literature by identifying the importance of spaces in conducting strategic work, and providing insight into way that these spaces are constructed