Paper Session I-B - Nuclear Thermal Rocket Propulsion Application to Mars Missions

This paper discusses vehicle configuration options using nuclear thermal rocket (NTR) propulsion application to Mars missions. A reference mission in 2016 using an opposition-class Mars transfer trajectory is assumed. The total mission duration is 435 days. A single 75,000-lb-thrust nuclear engine is used for all major propulsive maneuvers. The studies indicate that three perigee kick burns upon leaving Earth result in the lowest stage weights required in low Earth orbit (LEO). The stay time on Mars is assumed to be 30 days. On the interplanetary return leg en route to Earth, a gravity assist by Venus is employed. The reference mission assumes that the nuclear engine delivers a specific impulse of 925 s with an engine thrust-to-weight ratio of 4. The total stage thrust-to-weight ratio was 0.06. To determine which engine parameters were most critical to good mission performance, calculations were performed over arange of specific impulses and thrust-to-weight ratios. One of the major conclusions resulting from this study is that engine specific impulse is the single most important engine parameter in reducing overall stage weight, provided the engine thrust-to-weight ratio is above approximately 4. Lower engine thrust-to-weight ratios were found to incur severe performance penalties

Paper Session I-B - Autonomous Robotic Systems For SEI Tasks

On the 20th anniversary, in 1989, of our country\u27s triumphant first landing on the surface of our moon, the President of the United States once again challenged the nation to excel in space. Since that time, a series of outreach efforts was initiated by NASA to the aerospace industry, federal agencies, and the public. In addition, the Vice President of the United States chartered an Advisory Committee on the Future of the U.S. Space Program. At this writing, the AIAA has submitted a report on their canvass of the aerospace community, and the Advisory Committee report has been published. The synthesis group is in the conclusion preparation phase and should have the report completed by the time of this conference. Although each of these groups has taken different approaches, a consensus does appear that agrees with the President\u27s objectives. Whether the schedule or architectures agree, they all recommend a ...\u27 \u27balanced Space Program for America. We will, within budgetary limits, reenergize our country\u27s thrust into space through a renewed dedication toward the long-term magnet for the manned space program ... the human exploration of Mars. This, of course, is the long-term goal coupled with the science, mission-to-planet Earth, expanded technology and development of a robust space transportation system that make up the balanced program recommended. The authors do not disagree with the goals, objectives, or recommendations of the two reports published to date nor will we differ with the synthesis conclusions after they become apparent. We will briefly summarize the results of an .analysis conducted by McDonnell Douglas and Eagle Engineering in the second and third quarters of CY9Q. The results will show the benefits of space programs and suggest an overall approach to space architecture that could help maximize the world benefits of space while still meeting the overall objectives of the three sets of recommendations mentioned above. We acknowledge the work of the con- \u27 tributors to the AIAA report and to numerous NASA studies of specific endeavors such as the Lunar Energy Enterprise study. This paper is a much shortened version of the entire treatment. A more complete presentation will be available from the authors at the conference if desired

Empowering refugee families in transit: the development of a culturally competent and compassionate training and support package

Background: Refugee parents who fled conflicts suffered violence and traumas and face huge challenges in supporting the health and welfare of their children whilst in transit. Aims: To describe the development of a culturally competent and compassionate Training and Support Package (TSP) for nurses, social and health care workers and volunteers, with a focus on parenting needs among unsettled refugees fleeing conflict. Methods: The multi-method approach included: a scoping review covering parenting needs of refugees fleeing conflict zones; collection of stories from refugee parents, healthcare workers and volunteers via a mobile application; discussions between team members; a piloted and evaluated curriculum. Results: High levels of family distress and deterioration of parental identity were identified. Informed by these results, the curriculum is articulated along twenty bite-sized learning units, covering four age stages of childhood as well as targeting adults’ wellbeing. Pilot training was evaluated positively confirming feasibility and usefulness of TSP. Conclusions: Unsettled refugee parents fleeing conflicts face psychosocial and practical difficulties negatively affecting their parenting skills. Care workforce should be trained in order to provide culturally competent and compassionate support to help these families. Open access digital platforms are promising as autodidactic and self-help tools amongst hard-to-reach populations

Mesenchymal stem cells derived from inflamed dental pulpal and gingival tissue: a potential application for bone formation

Background: Chronic periodontal disease is an infectious disease consisting of prolonged inflammation of the supporting tooth tissue and resulting in bone loss. Guided bone regeneration procedures have become common and safe treatments in dentistry, and in this context dental stem cells would represent the ideal solution as autologous cells. In this study, we verified the ability of dental pulp mesenchymal stem cells (DPSCs) and gingival mesenchymal stem cells (GMSCs) harvested from periodontally affected teeth to produce new mineralized bone tissue in vitro, and compared this to cells from healthy teeth. Methods: To characterize DPSCs and GMSCs, we assessed colony-forming assay, immunophenotyping, mesenchymal/stem cell phenotyping, stem gene profiling by means of flow cytometry, and quantitative polymerase chain reaction (qPCR). The effects of proinflammatory cytokines on mesenchymal stem cell (MSC) proliferation and differentiation potential were investigated. We also observed participation of several heat shock proteins (HSPs) and actin-depolymerizing factors (ADFs) during osteogenic differentiation. Results: DPSCs and GMSCs were successfully isolated both from periodontally affected dental tissue and controls. Periodontally affected dental MSCs proliferated faster, and the inflamed environment did not affect MSC marker expressions. The calcium deposition was higher in periodontally affected MSCs than in the control group. Proinflammatory cytokines activate a cytoskeleton remodeling, interacting with HSPs including HSP90 and HSPA9, thioredoxin-1, and ADFs such as as profilin-1, cofilin-1, and vinculin that probably mediate the increased acquisition in the inflamed environment. Conclusions: Our findings provide evidence that periodontally affected dental tissue (both pulp and gingiva) can be used as a source of MSCs with intact stem cell properties. Moreover, we demonstrated that the osteogenic capability of DPSCs and GMSCs in the test group was not only preserved but increased by the overexpression of several proinflammatory cytokine-dependent chaperones and stress response proteins

A Case of Intra and Extra-vascular Lipoma of the Subclavian Vein

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Comparison of questionnaire exposure data to land cover map from geographical information system to assess passive exposure to pesticides: a methodological study

Background: Exposure assessment based on questionnaires is frequently implemented in case-control studies, but possible information and recall bias could lead to misclassification of exposure. Methods: We evaluated passive exposure to pesticides as possible environmental risk factors for amyotrophic lateral scle-rosis (ALS) using a questionnaire mailed to participants in a case-control study in Emilia Romagna and Sicily. Results from questionnaire assessment were com-pared with a remote sensing methodology based on geographical information system, i.e. the land use within a circular 100-meter area around subjects' residence. Since land cover maps were made available only about once every ten years, we used the 2003 and 2009 maps for Emilia-Romagna and Sicily, respectively. Thus, we estimated the percent-age of 'recent' total crop density close to each participant's home, setting positive exposure above 10% of land use. Finally, we calculated the agreement between the two different methodologies using Cohen‟s kappa coefficients for all subjects, cases and controls. Results and Conclusions: Cohen's kappa was 0.364 (95% CI 0.158-0.569) in total population, 0.378 (0.056-0.700) in cases and 0.354 (0.090-0.618) in controls using the most recent land use map available close to year of case diagnosis. Although a moderate-to-low agreement could be seen between two exposure methods, similar results were found in both cases and controls, suggesting that no recall bias occurred in the most recent period. In the future, we plan to compare such agreement using historical residence over the 20-30 years prior to diagnosis, in order to validate the long-term exposure to pesticides in subjects