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Evidence for lunar tide effects in Earthโs plasmasphere
Get PDFTides are universal and affect spatially distributed systems, ranging from planetary to galactic scales. In the EarthโMoon system, effects caused by lunar tides were reported in the Earthโs crust, oceans, neutral gas-dominated atmosphere (including the ionosphere) and near-ground geomagnetic field. However, whether a lunar tide effect exists in the plasma-dominated regions has not been explored yet. Here we show evidence of a lunar tide-induced signal in the plasmasphere, the inner region of the magnetosphere, which is filled with cold plasma. We obtain these results by analysing variations in the plasmasphereโs boundary location over the past four decades from multisatellite observations. The signal possesses distinct diurnal (and monthly) periodicities, which are different from the semidiurnal (and semimonthly) variations dominant in the previously observed lunar tide effects in other regions. These results demonstrate the importance of lunar tidal effects in plasma-dominated regions, influencing understanding of the coupling between the Moon, atmosphere and magnetosphere system through gravity and electromagnetic forces. Furthermore, these findings may have implications for tidal interactions in other two-body celestial systems
An autoethnography of automated powerlessness: lacking platform affordances in Instagram and TikTok account deletions
Get PDFSituated within the field of platform governance studies, this paper shares findings from an โautoethnography of automated powerlessnessโ, drawing from the researcherโs disempowering experience of being a heavily moderated social media user. Using theoretical frameworks blending affordances and World Risk Society theories, this paper contextualises my experiences of moderation of my pole dance instructor, activist and blogger account @bloggeronpole from February to October 2021 within social mediaโs broader de-platforming of nudity and sexuality, finding fallacies within platformsโ own affordances, which lack mechanisms to aid or rehabilitate de-platformed accounts. With little to no information from platforms about the details of their moderation, qualitative, ethnographic and autoethnographic explorations of their governance are all users currently have to fight and understand their puritan, patriarchal censorship of nudity and sexuality, which are often conflated with risk. This study concludes with recommendations for different options for better, more equal and community focused moderation
Overview of special issue on urban cycling: Rationalities, justice, safety, and geographical analysis
Get PDFBetween โEmpoweringโ and โBlamingโ Mechanisms in Developing Political/Economic Responses to Climate Change
Get PDFThis conceptual paper reviews four dimensions of the climate change (CC) debate concerning perception, framing, and political and economic dimensions of CC. It attempts to address the question posed by sociological research as to what can be done to reduce the social forces driving CC. In doing so, it attempts to uncover mechanisms that delay or prevent the social change required to combat CC. Such mechanisms call into question the Ecological Modernization Theory's assumption that modern societies embrace environmental sustainability with no radical intervention to change the social, political, and economic order. It specifically considers how the representation of CC as a distant phenomenon, in both temporal and physical terms, might contribute to social disengagement. A reflection on the interdependencies among science, political economy, media, and individual perceptions guides this paper. All these social forces also shape the CC discourse in diverse ways according to the evolution of the phenomenon over time (in scientific, but also in political and economic terms) and in relation to its spatial dimension (global/national/local). The variety of climate discourses contributes to increasing political uncertainty; however, this is not the only factor that generates confusion around the CC. Multiple and contrasting information might trigger a โblaming/empowering gameโ that works at various levels. This mechanism simultaneously promotes the necessity for sustainable development and perpetuates โbusiness as usual-orientedโ practices. Implementing sustainable development is therefore constantly undermined by a difficulty in identifying โheroesโ and โdevilsโ in the context of CC
Studying Perfectionistic Climates
Get PDFIn studying perfectionism in sport, dance, and other performance environments, researchers have typically conceptualised perceptions of external pressure to be perfect as a reflection of a performerโs perfectionistic personality. However, we believe that when some performers report the experience of external pressure, their experiences are not solely generated internally. Rather, for many performers, they are reporting experiences that are to a much greater degree rooted in the behaviour of others. The major theme forwarded in this chapter is that some performers โ regardless of how perfectionistic they are themselves โ will have the misfortune of encountering specific others and environments that are highly perfectionistic. We are referring particularly to coaches, teachers and instructors, and clubs, teams, and classes, and how these leaders can imbue these environments with perfectionistic messages and cues. To elaborate on this theme, in the current chapter, we introduce, define, and discuss a new construct that captures the degree to which an environment is perfectionistic โ perfectionistic climate
Barriers and Gateways to Cleaning Up Earth Orbit: The Legal, Economic, and Political dimensions of Debris Remediation
Get PDFThe preponderance of human-made debris in Earth orbit has long been recognized as a significant threat to continued safe operations in space. National space agencies and private space companies are paying considerable attention to the technical questions surrounding the active removal of debris (ADR). Nonetheless there are still significant legal, economic, and geopolitical questions that need to be addressed before any meaningful and sustained industry around the removal of debris can be established. This discussion will focus on identifying the legal issues of responsibility, jurisdiction and liability and proposing possible solutions within the current nexus of international agreements. Yet these must be considered alongside the economic roadblocks to funding ADR; the challenges for states looking to collaborate in current geopolitical circumstances; and the often overlooked โdata deficitโ in respect of the space surveillance and tracking (SST) capabilities needed to enable the safe removal of debris. It is contended that any system for managing ADR, Debris Mitigation and general protection of the space environment should not emerge in isolation. A coherent system of managing and coordinating the orbital environment needs to be developed. This article will argue that it is for individual nations to show political leadership and an economic commitment to properly manage the delicate extraterrestrial environment. Failure to do so will represent a missed opportu nity and leave a troubling legacy for future generations
Chemical composition, pharmacodynamic activity of processed Aconitum brachypodum Diels., and molecular docking analysis of its active target
Get PDFAconitum brachypodum Diels. (AB.) is a plant of Aconitum L. The dried roots of AB have analgesic and anti-inflammatory activity. However, the processing is required to reduce toxicity before use because of its high toxicity. Studies on the toxicity, pharmacodynamics, and chemical composition of processed Aconitum brachypodum Diels. PAB. are still lacking at present. In this study, the composition changes of AB and PAB were determined by ultra-performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (UPLC-QE-Orbitrap-MS). The intensity of diester alkaloids was greatly reduced, while the monoester alkaloids were significantly increased. An acute toxicity experiment was used to evaluate the toxicity differences between AB and PAB, while the acetic acid-induced writhing pain experiment and croton oil-induced ear edema experiment were applied to evaluate the analgesic and anti-inflammatory properties. The acute toxicity test of AB showed that the median lethal dose (LD50) was 1.37 g/kg, while the maximal feasible dose (MFD) of PAB was 30.0 g/kg. It was apparent that the toxicity of PAB was significantly reduced. The alkaloid component of PAB could significantly inhibit the miceโs ear edema and significantly reduce the writhing times of mice. Based on the above findings, ten compounds, including songoramine (1), neoline (2), bullatine C (3), dihydroatisine (4), bullatineA (5), maltol (6), 15-O-acetylsongorine (7), 15-O-acetylsongoramine (8), songorine (9), and aldohypaconitine (10) were isolated and identified from the alkaloid component of PAB. Compounds 4, 6, 8, and 10 were firstly separate from Aconitum brachypodum Diels. Finally, molecular docking to anti-inflammatory analgesic target protein was carried out. The results indicated that 15-O-acetylsongoramine has a strong binding ability with target proteins, which may interact with the target protein Akt1 of phosphatidylinositol-3-kinase/serine-threonine kinase (Pi3k/Akt) pathway, while, adjust the downstream nuclear factor kappa B (NF-ฮบB) signaling pathway to play an anti-inflammatory analgesic effect
Abrasive Wear Behavior of Alโ4Cuโ1.5MgโWC Composites Synthesized through Powder Metallurgy
Get PDFDifferent Alโ4Cuโ1.5Mg/WC composites were synthesized through powder metallurgy to establish the effect of WC particle addition on the abrasive wear behavior of an Alโ4Cuโ1.5Mg (wt. %) alloy. The wear tests were performed using a pin-on-disc tribometer at room temperature in dry conditions using SiC abrasive sandpaper as a counterbody and tribometer of linear configuration. The results showed that WC additions increase the hardness of the Alโ4Cuโ1.5Mg alloy due to the strengthening effect of particle dispersion in the aluminum matrix, which generates an improvement in the wear resistance of the composites by preventing direct contact of the sample with the counterbody, in turn delaying the plastic deformation phenomena responsible for the degradation sequence. In addition, the dominant wear mechanism was abrasive wear, and the increased friction coefficient did not bring a rapid wear rate, which was related to the enhanced deformation resistance due to the high hardness
โBecomingโ and โbeingโ a student: understanding the educational journey of social work students on work-based learning degrees in universities
Get PDFBased on a PhD study, this article explores the experiences of students living in Cumbria and North East England who were undertaking one of two work-based learning social work degrees, one at a local face-to-face university the other at a national distance learning university. Whilst there is a long history of universities in England providing work-based learning routes in social work education, 2010 witnessed a revitalisation with the introduction of graduate schemes followed by apprenticeships in 2018, all situated within local authorities. The article focuses in particular on the significance of identity for work-based learners during their educational journey of โbecomingโ and โbeingโ a student. By drawing on identity theory, the article analyses how identity is an important concept in understanding the challenges and opportunities for this group of students on their educational journeys into and through higher education. This includes learning for social work education providers about understanding the particular experiences of work-based learners and how to deliver social work education effectively for this group of students. The findings are relevant beyond England particularly as universities move to a more socially distanced mode of delivery as a result of the Covid-19 pandemic
Which COVID-19 information really impacts stock markets?
Get PDFInformation about COVID-19 abounds, but which COVID-19 data actually impacts stock prices? We investigate which measures of COVID-19 matter most by applying elastic net regression for measure selection using a sample of the 35 largest stock markets. Out of 24 measures, COVID-19 related Google search trends, the stringency of government responses and media hype prevail. These measures proxy for COVID-19 related uncertainty, the economic impact of lockdowns and panic-driven media attention respectively, summarizing key aspects of COVID-19 that move stock markets. Moreover, geographical proximity to the virusโs outbreak and a countryโs development level also matter in terms of impact