A Plum Story? Early Encounters and Colonial Views of the Safu in Central Africa, Seventeenth-Twentieth Centuries

The diversity of edible species originating in Africa is considerable, but the history of their use and domestication remains largely neglected, despite existing historical records. This essay aims to explore attitudes towards safu (Pachylobus edulis), a Central African fruit that defies Western categories. Based on more than one hundred archival documents, this study examines the history of the safu and the tree that produces it as seen by Europeans (German, English, Belgian, Spanish, French, Italian, Portuguese, Swedish, etc.) present in Central Africa. The documentation collected on safus and safu trees reflects not only local views of the species but also the broader European projects pursued on the continent and the vision of African foodways. Indeed, their valuation is symptomatic of food encounters and hierarchies during colonial settlement. More broadly, it reveals how subsistence and agriculture were viewed in the region: the ubiquity of this fruit tree around villages, as often reported, contrasts sharply with the historical narrative of the absence of African agriculture in the tropics. Finally, it shows how colonial enterprises, despite hindered dispersal and missed opportunities, circulated the species in different parts of the planet

Improvements in Modeling 90 degree Bleed Holes for Supersonic Inlets

The modeling of porous bleed regions as boundary conditions in computational fluid dynamics (CFD) simulations of supersonic inlet flows has been improved through a scaling of sonic flow coefficient data for 90deg bleed holes. The scaling removed the Mach number as a factor in computing the sonic flow coefficient and allowed the data to be fitted with a quadratic equation, with the only factor being the ratio of the plenum static pressure to the surface static pressure. The implementation of the bleed model into the Wind-US CFD flow solver was simplified by no longer requiring the evaluation of the flow properties at the boundary-layer edge. The quadratic equation can be extrapolated to allow the modeling of small amounts of blowing, which can exist when recirculation of the bleed flow occurs within the bleed region. The improved accuracy of the bleed model was demonstrated through CFD simulations of bleed regions on a flat plate in supersonic flow with and without an impinging oblique shock. The bleed model demonstrated good agreement with experimental data and three-dimensional CFD simulations of bleed holes

Dwelling on the right side of the curve: an exploration of the psychological wellbeing of parents of gifted children

Research has shown that parenting a child who is exceptional is difficult. Gifted children by statistical definition are exceptional and therefore, the experience of their parents should be an area of potential concern. The existing literature has largely overlooked the psychological wellbeing of the parents of gifted children. It has highlighted the concerns of the parents about their child, however the impact of these concerns on the parents’ psychological wellbeing has not been investigated systematically. Further, much of the literature has explored the lives of gifted children and their family using qualitative methods. This makes it difficult to compare the experiences of the children and parents to normative samples and to then draw conclusions as to whether there are measurable differences between the populations. In a cross-cultural (Australian and USA) study, parents who considered their child gifted were asked to complete an online survey. The behavioural characteristics of gifted children were examined with a commonly used standardised psychological measure of child behaviours. The parents of the children reported higher levels of a range of problematic behaviours including conduct, emotional difficulties, peer problems, and hyperactivity/inattention, and lower scores on prosocial behaviours. When twice exceptional children were removed from the analysis the results remained largely unchanged. In both countries, parents reported a moderate level of confidence in their child’s teacher and a moderate degree of satisfaction with the frequency of contact and nature of their relationship with their child’s teacher. Across all aspects of school experience as investigated by this study, the majority of parents were ambivalent. Problematic child behaviours have been shown to be negatively associated with parental psychological wellbeing and results showed this was true in the current sample. The parents completed standardised measures of mental health and parenting stress. They reported significantly higher levels of anxiety and higher scores on parenting stress. Multiple regressions showed that child behaviour was a key predictor for both measures of parental psychological wellbeing. Child conduct problems were strongly associated with parental anxiety. For parenting stress child conduct was again a significant predictor as were peer problems and poor prosocial behaviours. Lower levels of trust in the child’s classroom teacher were also a significant predictor of increased parenting stress. Again, removal of parents of twice exceptional children from the analysis had little impact on results. Findings of psychological distress in parents that was associated with their children’s problematic behaviour suggest a need to investigate the wellbeing of both parents and children more deeply. The high frequency of behaviour problems in the children suggests a need to broaden the definition of “gifted” so that it encompasses social, emotional, and intellectual characteristics. The findings also raise the question whether standardised psychological measures developed for the full range of intellectual ability are appropriate for the assessment of the social and emotional needs in this population

Can seed exchange networks explain the morphological and genetic diversity in perennial crop species? The case of the tropical fruit tree Dacryodes edulis in rural and urban Cameroon

Crop seed exchange networks, shaped by social dynamics, strongly influence the organization and breadth of plant diversity in human-managed environments. Integrating an urban and market perspective, this study explores the diversity dynamics of a socio-economically important Central African fruit tree species, the African plum tree. Tree owners in urban, peri-urban and rural sites use seeds from different origins as their main propagation material, leading to locational variations in genetic diversity and structure. This analysis contributes toward building a framework to inform the research agenda of cultivated African fruit trees, by highlighting the important role of urban centers in safeguarding crop genetic resources

Aerodynamic Shape Optimization of Supersonic Aircraft Configurations via an Adjoint Formulation on Parallel Computers

This work describes the application of a control theory-based aerodynamic shape optimization method to the problem of supersonic aircraft design. The design process is greatly accelerated through the use of both control theory and a parallel implementation on distributed memory computers. Control theory is employed to derive the adjoint differential equations whose solution allows for the evaluation of design gradient information at a fraction of the computational cost required by previous design methods. The resulting problem is then implemented on parallel distributed memory architectures using a domain decomposition approach, an optimized communication schedule, and the MPI (Message Passing Interface) Standard for portability and efficiency. The final result achieves very rapid aerodynamic design based on higher order computational fluid dynamics methods (CFD). In our earlier studies, the serial implementation of this design method was shown to be effective for the optimization of airfoils, wings, wing-bodies, and complex aircraft configurations using both the potential equation and the Euler equations. In our most recent paper, the Euler method was extended to treat complete aircraft configurations via a new multiblock implementation. Furthermore, during the same conference, we also presented preliminary results demonstrating that this basic methodology could be ported to distributed memory parallel computing architectures. In this paper, our concern will be to demonstrate that the combined power of these new technologies can be used routinely in an industrial design environment by applying it to the case study of the design of typical supersonic transport configurations. A particular difficulty of this test case is posed by the propulsion/airframe integration

Aerodynamic Shape Optimization of Supersonic Aircraft Configurations via an Adjoint Formulation on Parallel Computers

This work describes the application of a control theory-based aerodynamic shape optimization method to the problem of supersonic aircraft design. The design process is greatly accelerated through the use of both control theory and a parallel implementation on distributed memory computers. Control theory is employed to derive the adjoint differential equations whose solution allows for the evaluation of design gradient information at a fraction of the computational cost required by previous design methods (13, 12, 44, 38). The resulting problem is then implemented on parallel distributed memory architectures using a domain decomposition approach, an optimized communication schedule, and the MPI (Message Passing Interface) Standard for portability and efficiency. The final result achieves very rapid aerodynamic design based on higher order computational fluid dynamics methods (CFD). In our earlier studies, the serial implementation of this design method (19, 20, 21, 23, 39, 25, 40, 41, 42, 43, 9) was shown to be effective for the optimization of airfoils, wings, wing-bodies, and complex aircraft configurations using both the potential equation and the Euler equations (39, 25). In our most recent paper, the Euler method was extended to treat complete aircraft configurations via a new multiblock implementation. Furthermore, during the same conference, we also presented preliminary results demonstrating that the basic methodology could be ported to distributed memory parallel computing architectures [241. In this paper, our concem will be to demonstrate that the combined power of these new technologies can be used routinely in an industrial design environment by applying it to the case study of the design of typical supersonic transport configurations. A particular difficulty of this test case is posed by the propulsion/airframe integration