19 research outputs found

    Post-Flight Evaluation of Stardust PICA Forebody Heatshield Material

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    This presentation was part of the session : Sample Return ChallengesSixth International Planetary Probe WorkshopPhenolic Impregnated Carbon Ablator (PICA) was developed at NASA Ames Research Center under the lightweight ceramic ablator development program in the '80s. PICA has the advantages of low density (~ 0.27g/cc) coupled with efficient ablative capability at high heat fluxes making PICA an enabling technology for the Stardust mission. Three cores at key locations were extracted from the forebody heatshield of the Stardust Sample Return Capsule (SRC) post flight and evaluated. Core locations include a near stagnation core, a flank core and a segment taken from the shoulder of the heatshield. Evaluation included density profiles, recession determination, thermal analysis profile, PICA bondline examination, strength of remaining virgin PICA, emissivity profile, chemical analysis profile and microstructural analysis. Comparisons between experimental density profiles and profiles derived from FIAT, a tool used to predict ablative performance, are in good agreement. Recession comparisons from measured values and FIAT predictions are currently being obtained. In addition a laser scanning tool developed at ARC is being used to evaluate recession measurements and compare to experimental and predicted values. In general, the PICA material examined in the cores is in good condition and intact. Impact damage is not evident and the main degradation observed was that caused by heating on entry. A substantial amount of "virgin" PICA was present in all cores examined. It is noted that the post-flight analysis of the Stardust heat shield is especially important since PICA is baselined for both the Orion (CEV) and Mars Science Laboratory vehicles.NASA; NESC; Orion Thermal Protection System Advanced Development Projec

    Learning cooking skills at different ages: a cross-sectional study

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    Background Cooking skills are increasingly included in strategies to prevent and reduce chronic diet-related diseases and obesity. While cooking interventions target all age groups (Child, Teen and Adult), the optimal age for learning these skills on: 1) skills retention, 2) cooking practices, 3) cooking attitudes, 4) diet quality and 5) health is unknown. Similarly, although the source of learning cooking skills has been previously studied, the differences in learning from these different sources has not been considered. This research investigated the associations of the age and source of learning with the aforementioned five factors. Methods A nationally representative (Northern/Republic of Ireland) cross-sectional survey was undertaken with 1049 adults aged between 20–60 years. The survey included both measures developed and tested by the researchers as well as validated measures of cooking (e.g. chopping) and food skills (e.g. budgeting), cooking practices (e.g. food safety), cooking attitudes, diet quality and health. Respondents also stated when they learnt the majority of their skills and their sources of learning. The data was analysed using ANOVAs with post-hoc analysis and Chi2 crosstabs with a significance level of 0.05. Results Results showed that child (<12 years) and/or teen (13–18 years) learners had significantly greater numbers of, and confidence in, their cooking and food skills, cooking practices, cooking attitudes, diet quality (with the exception of fibre intake where adult learners were higher) and health. Mother was the primary source of learning and those who learnt only from this source had significantly better outcomes on 12 of the 23 measures. Conclusions This research highlights the importance of learning cooking skills at an early age for skill retention, confidence, cooking practices, cooking attitude and diet quality. Mother remained the primary source of learning, however, as there is a reported deskilling of domestic cooks, mothers may no longer have the ability to teach cooking skills to the next generation. A focus on alternative sources including practical cooking skills education starting at an early age is required. This study also highlights the need for further longitudinal research on the impact of age and source of learning on cooking skills

    Dental Adaptations of African Apes

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