Model insights into energetic photoelectrons measured at Mars by MAVEN

Photoelectrons are important for heating, ionization, and airglow production in planetary atmospheres. Measured electron fluxes provide insight into the sources and sinks of energy in the Martian upper atmosphere. The Solar Wind Electron Analyzer instrument on board the MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft measured photoelectrons including Auger electrons with 500 eV energies. A two-stream electron transport code was used to interpret the observations, including Auger electrons associated with K shell ionization of carbon, oxygen, and nitrogen. It explains the processes that control the photoelectron spectrum, such as the solar irradiance at different wavelengths, external electron fluxes from the Martian magnetosheath or tail, and the structure of the upper atmosphere (e.g., the thermal electron density). Our understanding of the complex processes related to the conversion of solar irradiances to thermal energy in the Martian ionosphere will be advanced by model comparisons with measurements of suprathermal electrons by MAVEN

Addiction in the Light of African Values: Undermining Vitality and Community

In this article I address the question of what makes addiction morally problematic, and seek to answer it by drawing on values salient in the sub-Saharan African philosophical tradition. Specifically, I appeal to life-force and communal relationship, each of which African philosophers have at times advanced as a foundational value, and spell out how addiction, or at least salient instances of it, could be viewed as unethical for flouting them. I do not seek to defend either vitality or community as the best explanation of when and why addiction is immoral, instead arguing that each of these characteristically African values grounds an independent and plausible account of that. I conclude that both vitalism and communalism merit consideration as rivals to accounts that Western ethicists would typically make, according to which addiction is immoral insofar as it degrades rationality or autonomy, as per Kantianism, or causes pain or dissatisfaction, à la utilitarianism

Tackling child poverty in South Africa: Implications of ubuntu for the system of social grants

In the South African context both liberal and – in the form of the southern African idea of ubuntu – more communitarian and relational discourses of citizenship can be seen. The policy framework to tackle child policy, however, is dominated by the framework of liberal citizenship, most clearly through the Bill of and the various social grants. Using analyses from an original microsimulation model developed by one of the authors the paper shows however how a neglect of children’s relationships and inter-connectedness with their adult parents/carers in the current liberal citizenship inspired policy approach limits the effectiveness of this child poverty strategy. The empirical analyses demonstrate how a greater recognition in policy of the relational principles of ubuntu through more fully addressing the needs of children’s parents/carers via the creation of a comprehensive social security grant for working age adults is needed to effectively reduce child poverty as well as working age poverty