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Innovative Hands-On Approach for Magnetic Resonance Imaging Education of an Undergraduate Medical Radiation Science Course in Australia: A Feasibility Study
No full textAs yet, no study has investigated the use of a research magnetic resonance imaging (MRI) scanner to support undergraduate medical radiation science (MRS) students in developing their MRI knowledge and practical skills (competences). The purpose of this study was to test an innovative program for a total of 10 second- and third-year students of a MRS course to enhance their MRI competences. The study involved an experimental, two-week MRI learning program which focused on practical MRI scanning of phantoms and healthy volunteers. Pre- and post-program questionnaires and tests were used to evaluate the competence development of these participants as well as the program’s educational quality. Descriptive statistics, along with Wilcoxon signed-rank and paired t-tests, were used for statistical analysis. The program improved the participants’ self-perceived and actual MRI competences significantly (from an average of 2.80 to 3.20 out of 5.00, p = 0.046; and from an average of 34.87% to 62.72%, Cohen’s d effect size: 2.53, p < 0.001, respectively). Furthermore, they rated all aspects of the program’s educational quality highly (mean: 3.90–4.80 out of 5.00) and indicated that the program was extremely valuable, very effective, and practical. Nonetheless, further evaluation should be conducted in a broader setting with a larger sample size to validate the findings of this feasibility study, given the study’s small sample size and participant selection bias
Exploring Physical Activity in Individuals With Type 2 Diabetes Mellitus and Lower Limb Complications: A Scoping Review
No full textAim: To synthesise contemporary evidence on physical activity (PA) levels in people with type two diabetes and lower limb complications (i.e., foot ulcer, peripheral neuropathy [PN], peripheral arterial disease and amputations).
Methods: A scoping review following the JBI methodology was conducted using six databases: Medline, Embase, PubMed, Cochrane Library, SPORTDiscus and CINAHL. We included observational studies that primarily examined PA (all levels and types) in people with diabetes-related lower limb complications. Studies published before December 2024 were included. We excluded reviews, intervention studies, and studies that examined the association between PA and T2DM risks. Findings were collated into tables and figures and reported narratively.
Results: Sixteen studies met the inclusion criteria. Participants were reported to have PN, foot ulcer, peripheral arterial disease, or lower limb amputation. PA was assessed either by questionnaires or activity trackers. PA levels were reported as step count, duration of PA of different intensities, time spent in various postures, gait velocity, step rate and activity score. Mean daily step counts ranged between 1721 (amputation) and 7754 (PN). Mean moderate-intensity PA was reported to be 2 min per day (amputation) to 37 min per day (PN).
Conclusion: People living with diabetes-related lower limb complications engage in low levels of PA. The findings suggest that people with more severe lower limb complications engage in less PA than those with less severe lower limb complications. Future research should standardise PA measurement in individuals with T2DM-related lower limb complications and use the findings of this review to inform tailored, evidence-based recommendations
Dilution of precision for LEO satellite precise orbit and clock determination
No full textPrecise orbital and clock products for Low Earth Orbit (LEO) satellites are prerequisites for augmenting traditional Global Navigation Satellite Systems (GNSS) in the positioning, navigation and timing services. To effectively utilize LEO signals for real-time, high-precision positioning and timing on the ground, servers may need to broadcast LEO satellite orbital and clock products while simultaneously assessing their formal precision. The concept of Dilution of Precision (DOP) has been widely used to assess GNSS satellite geometry for ground-based receiver positioning and timing based on the Standard Point Positioning (SPP) technology. This concept can also be extended to LEO satellite Precision Orbit Determination (POD) and clock estimation. In this contribution, an extended concept of DOP is proposed for LEO POD using dual-frequency Ionosphere-Free (IF) observations. Similar to concepts of Position DOP (PDOP) and Time DOP (TDOP), a series of LEO orbit and clock DOP concepts are first defined, followed by a detailed analysis based on Reduced-Dynamic (RD) and kinematic batch least squares POD methods. Additionally, the correlations between the radial, along-track and cross-track LEO orbits and the LEO satellite clocks are assessed for the RD and kinematic POD modes. Based on real GPS+Galileo observations collected onboard the Sentinel-6A satellite, the DOP of LEO orbits and clocks among four strategies are calculated to evaluate the formal precision, i.e., the GPS-only RD (RD-G), GPS-only kinematic (KN-G), GPS+Galileo RD (RD-GE) and GPS+Galileo kinematic (KN-GE) modes. The RD-GE mode can achieve the highest formal precision for both orbit and clock, with a 7-day average orbit DOP of 0.87, 1.16, and 0.91 along the radial, along-track, and cross-track directions, respectively, and a clock DOP of 5.81. It was found that increasing the number of GNSS observations, and accordingly the geometry of their transmitting satellites, can significantly reduce the DOPs for the kinematic LEO satellite orbits and clocks. With the average number of GNSS satellites increasing from 7 to 14, the 7-day average percentage improvements in the DOPs in the radial orbits (RDOP), along-track orbits (SDOP), cross-track orbits (WDOP) and clocks (TDOP) are 32.6%, 37.3%, 40%, and 19.8%, respectively. However, increasing the number of GNSS observations has limited improvements on the RD POD, with improvements in the radial orbits and clocks amounting to 17.1% and 12.0%, respectively. It was also verified that the correlations between the radial orbits and the clocks are significantly reduced in the RD modes compared to the KN modes, i.e., from -0.31 to 0.05 in the GPS+Galileo case on average and from -0.34 to 0.1 in the GPS-only case
Global Englishes: Counteracting Internalized English Superiority, Challenging Problematic Identities, and (Re)Negotiating Agency
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Constant Connectivity and its Impact on Employee Well-being: A Mediation and Moderation Analysis
Get PDFThe advent and integration of mobile information and communication technology, high-bandwidth cellular services, laptops and mobile phones have created a boundaryless workspace where employees are expected to remain constantly connected for work purposes even after hours. Based on 218 online panel data, this study measured the conditional direct and indirect impact of constant connectivity after work hours on employee well-being and the mediating role of cognitive overload and mobile work device anxiety. Data was collected two times, T1 and T2, with a minimum gap of two weeks. The independent variable, mediators and moderators, were collected in T1, and the dependent variable was collected in T2. Cognitive overload negatively mediated the relationship between constant connectivity and employee well-being. No mediation was observed through work device anxiety; however, in the presence of a coping approach, a positive moderated mediation was observed through work device anxiety. An academic discourse of constant connectivity as a job resource, its use to gain other resources and the loss of resources due to constant connectivity has been affirmed in this study. In future, taking forward from this theoretical contribution, a greater in-depth study on the relationship between constant connectivity and employee well-being can be conducte
Generative Imaginaries of Australia: How Generative AI Tools Visualize Australia and Australianness
No full textGenerative AI (GenAI) has the potential to “imagine,” create, and render novel images in a seemingly endless combination of possibilities. However, the capacity of digital technologies to reduce cultural paradigms though the algorithmic monocultures they produce is well documented. As GenAI evokes powerful imaginaries, it is vital to ask what sorts of stories are included, and who is made more and less visible in them. To answer this, the authors tested a series of prompts across five of the largest commercially available GenAI engines—Adobe Firefly, Dream Studio, Dall-E3, Meta AI, and Midjourney. The prompts were “Australian-centric” in nature, designed to elicit the visual data of Australia through the lens of GenAI. Through an analysis of a corpus of approximately 700 images, the authors found that GenAI frequently invokes tired and cliched tropes to communicate “Australianness,” such as depictions of red dirt, Uluru, the “outback,” and a sense of wildness, in both its wildlife and in its depictions of “typical” Indigenous Australians. Various forms of bias were evident in the visualizations produced. The optics and interpretation of these images spans the puzzling to the troubling; this paper contends that “Australiana” as a category surfaces the limitations and blind spots of GenAI. Moreover, GenAI operates as something of a cultural time machine, surfacing old and defunct caricatures of Australianness despite the seeming novel newness of the “GenAI moment.
Searches for black hole candidates in the era of large-scale optical surveys
Get PDFThis thesis uses observations to understand the Galactic population of stellar-mass black holes and neutron stars. We place detailed constraints on the deaths of massive stars, and refine existing, and test new, methods for identifying stellar-mass black holes in binaries with a star. We find the methods tested produce samples dominated by non-black hole systems. Finally, we identify and investigate an exotic triple system in the Large Magellanic Cloud that may host a black hole
The Facial Approximation of the Skull Attributed to Jan Žižka (ca. AD 1360–1424)
Get PDFThe present study aims to approximate the face from the alleged skull of Jan
Žižka (ca. AD 1360–1424), a military commander and national hero in the Czech Republic.
Found in 1910, the skull has only a fraction of its original structure, which required an initial
effort to reconstruct the missing regions from data collected in CT scans of living people’s
heads. The forensic facial approximation consisted of projecting the skin boundaries with
soft tissue markers and cross-referencing data from statistical projections from CT scans
of living people and the use of the anatomical deformation technique, where the digital
head of a virtual donor was adjusted until it matched the alleged skull of the Czech general.
The final face was the result of the cross-referencing of all data and the completion of the
structure respected the iconography attributed to Jan Žižk
Spatiotemporal evolution of long-term slow slip events at the Hikurangi Subduction Zone, New Zealand (2021-2023): implications for seismic activity
Get PDFVarious slow slip events (SSEs) with distinct characteristics have been detected globally, particularly in regions with dense Global Navigation Satellite Systems (GNSS) networks. In the Hikurangi subduction zone of New Zealand, SSEs frequently occur alongside seismic activity, especially in the Manawatu and Kapiti regions. This study analyzes the 2021–2023 Kapiti-Manawatu long-term SSE using daily displacement data (2019–2023) from 53 GPS stations. The network inversion filter (NIF) method is applied to extract slow slip signals, revealing spatial migration with alternating slip between Kapiti and Manawatu, characterized by distinct phases of acceleration and deceleration. Manawatu exhibits higher slip rates, exceeding 4 cm/month, with greater cumulative slip and surface displacement than Kapiti. A moderate temporal correlation (coefficient 0.59) between seismic activity in the region and slip acceleration in Manawatu suggests that seismic events may contribute to the slip, while no significant correlation is observed in Kapiti