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Self-annealing behaviour of an Mg-Dy alloy processed by high-pressure torsion
No full textAn investigation was conducted to evaluate the microstructure, texture and microhardness of an Mg-0.4Dy (wt.%) alloy processed by high-pression torsion (HPT) for 15 turns and then self-annealed at ambient temperature for six years. Electron backscatter diffraction (EBSD) and Vickers microhardness were carried out near the centre, mid-radius and edge of each disc. The results show that self-annealing leads to a slight increase in the average grain size from 0.7 to 1 µm. The basal texture was retained at the centres and edges of the discs while the C1-fiber vanished near the mid-radius of the self-annealed disc. The value of the microhardness remained constant along the radii of the discs but the dislocation density, originating from the geometrically necessary dislocations (GND), increased significantly after self-annealing due to the development of sub-grain boundaries with misorientations of 2°< θ <5°. Based on these results, it is concluded that self-annealing of the HPT-processed Mg-0.4Dy alloy is controlled by a recovery process
The ichnology of White Sands (New Mexico): Linear traces and human footprints, evidence of transport technology?
Full text linkA travois is crafted from one or more wooden poles and is one of the simplest prehistoric vehicles. Although these devices likely played vital roles in the lives of ancient peoples, they have low preservation potential in the archaeological record. Here we report linear features associated with human footprints, some of which are dated to ∼22,000 years old, preserved in fine-grained sediments at White Sands National Park (New Mexico, USA). Using a range of examples, we identify three morphological types of trace in late Pleistocene sediments. Type I features occur as single, or bifurcating, narrow (depth > width) grooves which extend in planform from 2 to 50 m in length and trace either straight, gently curved or more irregular lines. They are associated with human footprints, which are truncated longitudinally by the groove and are not associated with other animal tracks. Type II examples are broader (width > depth) and form shallow runnels that typically have straight planforms and may truncate human footprints to one side. Type III examples consist of two parallel, equidistant grooves between 250 and 350 mm apart. They trace gently curving lines that can extend for 30+ m. Human footprints are associated with these features and may occur between, and to the side of, the parallel grooves. We review a range of possible interpretations including both human and non-human explanations and conclude that the most parsimonious explanation is that they represent drag marks formed by travois consisting of a single pole or crossed poles pulled by humans, presumably during the transport of resources. As such this unique footprint record may represent one of the earliest pieces of evidence for the use of transport technology
Concurrent validity of skin-based motion capture systems in measuring dynamic lumbar intervertebral angles
Full text linkSpine kinematics are commonly measured by external sensors such as motion capture and accelerometers. However, these skin-based measures cannot directly capture intervertebral motion of the lumbar spine. To date, research in this area has focused on the estimation of intervertebral kinematics using static trials but no study has analyzed agreement throughout the dynamic range of motion. This study investigated the agreement between skin-based sensors (accelerometers and motion capture) and quantitative fluoroscopy (QF) in measuring lumbar spine kinematics for the duration of complete flexion and extension motion in a healthy female population. Twenty female participants (age 30–57, BMI < 30) were guided through a standing flexion and extension bending protocol while spine kinematics were concurrently measured by QF (L2, L3, L4, L5, and S1) and motion capture sensors and accelerometers positioned over the spinous processes of L2, L4, and S1. Intervertebral angles (L2-L4, L4-S1, L2-S1) and individual vertebrae levels were compared between measures. Non-parametric limits of agreement between QF and skin-based markers were greatest at the end-range of motion for both flexion and extension, but differences increased variably between participants, sometimes over-and sometimes underestimating angles, thus, disproving the common assumption that it increases linearly. The two skin-based marker systems showed good agreement with one another showing that they can be used interchangeably but they can only be used to estimate lumbar spine kinematics. Normalizing angles to a change in angle and considering the posture of instrumentation would be beneficial to reduce potential sources of errors
The Case of the Maldives: Has the COVID-19 Pandemic Changed Luxury Consumers’ Behavior Toward Sustainability?
Full text linkThis study examines luxury tourists’ behavior toward sustainability in the aftermath of the pandemic, with a particular focus on the Maldives, a destination renowned for both its luxury offerings and commitment to sustainable practices. A qualitative approach was employed, featuring structured interviews with one hundred European tourists who had visited the Maldives and stayed at luxury resorts, alongside semi-structured interviews with three tour operator managers who sell the destination. In addition, secondary data provided by the tour operator were used to support the analysis and triangulate the data for more robust findings. The results show a significant shift in consumer attitudes: luxury travelers have become increasingly sensitive to sustainability and the protection of the environment since the pandemic. The tourists in the sample reported heightened awareness of their personal environmental impact and a greater desire to mitigate it. Furthermore, participants expressed a willingness to pay a premium for environmentally sustainable services and products, demonstrating a clear preference for businesses that can substantiate their eco-friendly practices through credible certifications and accreditations. These findings highlight the growing importance of sustainability in shaping luxury consumer behavior in the post-pandemic era
Lower-limb neuromuscular electrical stimulation (NMES) for people with chronic kidney disease undergoing dialysis (Protocol)
Full text linkThis is a protocol for a Cochrane Review (intervention). The objectives are as follows: To assess the effects of neuromuscular electrical stimulation (NMES) on muscle structure and function in people undergoing dialysis
Online Social Capital Contribution to Mental Health: A Cross-sectional Study
Full text linkBackground: Declining student mental health is a growing concern, with over 60% of college students experiencing mental health issues, such as depression, exacerbated by the COVID-19 pandemic. Social capital is known to buffer against mental health challenges by promoting connection and support. This study aimed to examine the latent construct of online social capital in the context of COVID-19 and further test the relationship between multidimensional online social capital and mental health among university students at Shiraz University. Methods: A quantitative study was conducted with 600 students at Shiraz University. Data were collected using questionnaires measuring online social capital (number of networks, usage, and activity level) and mental health. Likert scales were used, with lower scores indicating better mental health. Statistical analyses included Pearson correlation coefficient, path analysis, and regression analysis. Results: A significant negative correlation was found between online social networks (r=-0.137, P<0.05) and mental health, suggesting that higher engagement in these networks is linked to better mental health. Trust (r=-0.129, P<0.05) and social support (r=-0.027, P<0.05) within online networks showed negative correlations with mental health, indicating that increased trust and support are associated with improved mental health. Path analysis revealed that all dimensions of online social capital influence mental health, with trust and social support identified as the strongest predictors. Conclusion: The research underscores the importance of universities fostering online social networks and initiatives to enhance student mental health by cultivating social support and trust. Increased engagement in online social networks, along with higher levels of trust and social support, is linked to improved mental well-being among university students
Turkish freshwaters as a case of rising invasion risk of aquarium fishes under climate change
Full text linkClimate change is expected to increase the invasiveness of non-native aquarium fish, yet national assessments rarely consider future warming conditions. We screened 46 popular ornamental freshwater fish imported into Türkiye for invasion risk. Each species received a Basic Risk Assessment (BRA) score under current conditions and an adjusted Climate Change Assessment (CCA) score under regional warming scenarios. The BRA classified 12 species (26.1%) as high risk, while under the CCA, this rose to 16 species (34.8%). Four species, namely goldfish Carassius auratus, common carp Cyprinus carpio, vermiculated sailfin catfish Pterygoplichthys disjunctivus, and leopard pleco P. gibbiceps, reached very high-risk status. Climate change adjustment resulted in an increase in the basic scores for 34 species, a decrease for three, and no change for nine. Seven species achieved the maximum increment of + 12 under predicted climate change conditions. Our results show that marginal habitats, such as thermal springs and effluent canals, could become suitable for these species, even as water stress in Central Anatolia threatens both native and invasive species. We recommend dynamic, climate-aware risk protocols, combined with empirical validation via field and eDNA monitoring, and a precautionary ‘whitelist’ import system based on robust risk screening protocols as applied in this study
Evaluating post 2024 election scenarios for the UK based on political party manifestos
Full text linkManifestos provide a vision for political parties to enact if elected to government. While manifestos may not be enacted in full, they provide some of the best information for the public in deciding how to vote. However, manifestos tend to contain both enactable policies (e.g., tax cuts) and outcomes or visions of what these policies may achieve for society (e.g., higher disposal income). These outcomes may be deliberately misleading, inaccurate or only a partial picture of how policies will materialise, as it is unlikely a single policy will influence a single outcome. This work creates a complex system model of the economic, societal and environmental landscape of the UK and assesses how it would be affected if political parties enacted their 2024 general election manifesto policies in full. Our model creates a more complete picture of how the UK may look under different parties, rather than examining the manifestos alone (using data solely from manifestos almost 30% of our model’s node values had no information, falling to just 5% after running the models).The model also has the capacity to provide a holistic reflection of the parties manifesto plans, illustrating the impacts each party’s policies could have, should they be enacted. Prior to integrated analysis the most right-wing of the parties studied; Reform UK, aligned strongly with the Conservative party, however, post analysis Reform became a clear outlier. We also demonstrate unintended, misreported or indirect effects of policies. Most notably,
parties who had the strongest tax cutting policies resulted in lower average incomes and higher levels of inequality in society, despite the rhetoric provided for these policies in the party manifestos. The results demonstrate the ability to integrate multiple types of information across political, economic, environmental, and social landscapes to help visualise implications of policy and politics more widely
Heading Towards a Safer Future? An exploration of elite male footballers’ perceptions towards heading and the Heading Guidelines in England.
No full textObjective: To explore perceptions of professional male footballers from an English Premier League club on heading in football and the Football Association’s (FA) Heading Guidelines.
Design: Focus group interview using a six-stage thematic analysis approach.
Setting: A Premier League Football Club in England.
Patients (or Participants): Eight male professional footballers.
Assessment of Risk Factors: Risk factors related to heading in football were discussed, including the safety of the game and long-term implications of heading.
Main Outcome Measures: Perceptions of heading in professional male football and the existing Heading Guidelines.
Results: Many footballers perceived the risk of sustaining a head injury to be much lower compared to other sports, and stated that the potential long-term risk associated with heading is not a pressing concern. Some justified continuing to play football and head the ball by reasoning that significant safety related changes have already been made to football. Heading is viewed as a fundamental skill, but players argue that it is already limited in training, further negating the need for Heading Guidelines. Finally, footballers expressed that if they were to follow current FA Heading Guidelines, this would negatively affect their development causing selection and career progression issues.
Conclusions: This is the first study to explore the perceptions of professional footballers related to heading and the current Heading Guidelines in England. To increase buy-in and adherence to current and future iterations of Heading Guidelines the perceptions of footballers and other key stakeholders should be taken into consideration, along with the scientific evidence base