Corona Threshold of Single and Multiple Conductor Lines

Corona is a self sustaining, often luminous discharge due to ionization adjacent to charged conductors, characterized by the electrodes having a small radius of curvature compared with the interelectrode gap. The display on a power transmission line is accompanied by a current between the conductors which to an engineer mean a power loss that should be minimized if unavoidable

Propellant Technologies: A Persuasive Wave of Future Propulsion Benefits

Rocket propellant and propulsion technology improvements can be used to reduce the development time and operational costs of new space vehicle programs. Advanced propellant technologies can make the space vehicles safer, more operable, and higher performing. Five technology areas are described: Monopropellants, Alternative Hydrocarbons, Gelled Hydrogen, Metallized Gelled Propellants, and High Energy Density Materials. These propellants' benefits for future vehicles are outlined using mission study results and the technologies are briefly discussed

Lake Michigan lower food web: Long-term observations and \u3ci\u3eDreissena\u3c/i\u3e impact

Lake Michigan has a long history of non-indigenous introductions that have caused significant ecological change. Here we present a summary of eight papers that document recent changes and the current state of the lower food web of southern Lake Michigan after the establishment of large dreissenid populations. Results are based on long-term data sets collected by federal and academic research and monitoring programs that place recent changes into a historic context. Dramatic and significant changes in the lower food web, such as the loss of the spring diatom bloom, large declines in phytoplankton productivity, and a decline of Mysis populations, were directly or indirectly attributed to the expansion of Dreissena rostriformis bugensis. Total phosphorus concentrations and loadings also have decreased in the last 20 years. Changes in the Lake Michigan ecosystem induced by D. r. bugensis have produced conditions in the offshore pelagic region that are similar to oligotrophic Lake Superior. The future state of the lower food web in southern Lake Michigan is difficult to predict, mainly because population trends of D.r. bugensis in cold, offshore regions are unknown. Hence, monitoring programs designed to collect long-term, consistent data on the lower food web of Lake Michigan are essential

Equal pay debates in international women’s football

One of the most visible discussion points around international level, professional women's football in recent years has been that of gender equitable payment of players. This chapter presents some of the cornerstones of the equal pay debates at play in women's football. First, the emergence of international women's football as a major force in the global sport nexus is highlighted, which has enabled women to be paid to play football as a profession. Second, the historical roots of equal pay debates are presented, before turning to the most public and high-profile remuneration dispute in the sport of football, that of the USWNT versus the United States Soccer Federation (USSF). In this chapter, we outline how the drawn-out legal process has undoubtedly contributed to greater pay parity on the international stage for many professional women footballers and conclude the chapter by offering our thoughts as to the significance, and future, of gendered pay debates in football

The scope of climate assemblies: lessons from the Climate Assembly UK

In recent times we have seen a spate of climate assemblies across Europe as the climate emergency gains increasing prominence in the political agenda and as the citizens’ assembly approach to public engagement gains popularity. However, there has been little empirical research on how the scope of citizens’ assemblies affects the internal logic of the assembly process and its impacts on external policy actors. This is a significant oversight given the power of agenda setting. It is also of particular importance for climate assemblies given the exceptional scale and complexity of climate change, as well as the need for co-ordination across all policy areas and types of governance to address it. In this paper, we start to address this gap through an in-depth case analysis of the Climate Assembly UK. We adopt a mixed methods approach, combining surveys of the assembly members and witnesses, interviews with the assembly members, organisers, MPs, parliamentary staff, and government civil servants, and non-participant observation of the process. We find that attempts to adapt the assembly’s scope to the scale of the climate change issue compromised assembly member learning, the co-ordination of the resulting recommendations, assembly member endorsement of the recommendations, and the extent of their impact on parliament and government. We argue that more democratization in setting the agenda could help combat these issues

Removing Orbital Debris with Lasers

Orbital debris in low Earth orbit (LEO) are now sufficiently dense that the use of LEO space is threatened by runaway collisional cascading. A problem predicted more than thirty years ago, the threat from debris larger than about 1 cm demands serious attention. A promising proposed solution uses a high power pulsed laser system on the Earth to make plasma jets on the objects, slowing them slightly, and causing them to re-enter and burn up in the atmosphere. In this paper, we reassess this approach in light of recent advances in low-cost, light-weight modular design for large mirrors, calculations of laser-induced orbit changes and in design of repetitive, multi-kilojoule lasers, that build on inertial fusion research. These advances now suggest that laser orbital debris removal (LODR) is the most cost-effective way to mitigate the debris problem. No other solutions have been proposed that address the whole problem of large and small debris. A LODR system will have multiple uses beyond debris removal. International cooperation will be essential for building and operating such a system.Comment: 37 pages, 15 figures, in preparation for submission to Advances in Space Researc

PREDICTORS OF POSTPARTUM DEPRESSION IN DUBAI, A RAPIDLY GROWING MULTICULTURAL SOCIETY IN THE UNITED ARAB EMIRATES

Background: Postpartum depression (PPD) is a significant public health problem adversely affecting mothers, their newborns, and other members of the family. Although PPD is common and potentially dangerous, only a minority of the cases are identified in primary health care settings during routine care, and the majority of depressed mothers in the community lies unrecognized and therefore untreated. Subjects and methods: In this study, a total of 1500 mothers were approached randomly, 808 accepted to participate, and 504 were within the inclusion criteria (women who had a birth of a singleton full-term healthy infant, had an uncomplicated pregnancy, and were within their one week to six months postpartum). The participants completed the Edinburgh Postnatal Depression Scale. Results: A total of 168 women had an EPDS score 10, yielding a crude prevalence rate of 33%. The prevalence of suicidal ideation was 14 out of 504 (3%), among which 11 (79%) had EPDS score of 10. We fitted multiple linear regression models to evaluate the predictors of variables measured on the EPDS scale. This model was statistically significant p<0.0001 in predicting the total EPDS score. Women\u27s employment status, baby\u27s birth weight, stressful life event and marital conflict were statistically significant predictors. Conclusions: The findings of this study are anticipated to entail the government and policy makers in the region to pay more attention to the apparently high prevalence of unrevealed PPD in the community. It is crucial to enhance screening mechanisms for early detection, providing interventions to manage symptoms, and at the same time mandating local guidelines to address the PPD pathology as a high priority for the UAE population