Technical prospects for utilizing extraterrestrial propellants for space exploration

NASA's LeRC has supported several efforts to understand how lunar and Martian produced propellants can be used to their best advantage for space exploration propulsion. A discussion of these efforts and their results is presented. A Manned Mars Mission Analysis Study identified that a more thorough technology base for propellant production is required before the the net economic benefits of in situ propellants can be determined. Evaluation of the materials available on the moon indicated metal/oxygen combinations are the most promising lunar propellants. A hazard analysis determined that several lunar metal/LOX monopropellants could be safely worked with in small quantities, and a characterization study was initiated to determine the physical and chemical properties of potential lunar monopropellant formulations. A bipropellant metal/oxygen subscale test engine which utilizes pneumatic injection of powdered metal is being pursued as an alternative to the monopropellant systems. The technology for utilizing carbon monoxide/oxygen, a potential Martian propellant, was studied in subscale ignition and rocket performance experiments

Connecting to the Sacred Through Contemplative Gaze

Visual contemplation can do more than convey images, it can transmit to the soul in ways that both inform and inspire. The artist shares the experience of empathic connection with another artist that may be cultivated by engaging with pieces that evoke emotional and somatic responses, and then entering into creative conversation with the artist by following their gestures, brush strokes, movement, marks, and color decisions

Recruitment Considerations for Christian, Dental, Short-Term Missions Relating to the Holistic Development of Dentists

A painful toothache often becomes unbearable and an unsightly smile can bring distress. Since tooth decay is the most widespread, chronic disease globally, mission trips by dentists can make an incalculable difference when they offer dental treatment to under-resourced people around the world. Dental ministration opens the door to a caring witness of God’s love where, as Jesus modeled, the physical touch may promote spiritual healing. Often, the recruitment of dentists for short-term, missions is challenging. This mixed-methods, phenomenological, research study was designed to explore the gap in dental, mission research concerning the recruitment of dentists as it relates to the benefits and the detractors of dental, short-term missions. The study utilized Christian dentists who returned 395 quantitative, research instruments from 15 countries, 44 states, and 43 Christian religious affiliations. Qualitative interviews with 60, short-term, mission-experienced, Christian dentists—who each averaged 55, short-term, dental missions—followed the quantitative study. The theory guiding this research was inspired by Lowe & Lowe (2018) who created a holistic model integrating six developmental aspects of personhood in the spiritual, intellectual, physical, moral, emotional, and social dimensions. Christian dentists revealed a relatively equal distribution in all of the beneficial motivators, highly endorsing participation in dental, short-term missions. The detractor responses were more diverse, with most Christian dentists affirming that their participation in dental, short-term missions would not be adversely affected by detractors

The Lost Dialogue of Artists: Negotiating the Conjuring of Art

This article examines the nature of the duologue between artist and creative source, as a lost interplay and negotiation within the gestation of the work in a uniquely individual language that can never be fully revealed, translated, or understood by a viewer. The author, an elder, late career studio artist, draws comparisons to sacred language and interpretation positing that the conversations and relationships that form between artist and art are very different from those between works of art and humanity and have never been appropriately examined from an insider perspective. She offers reflections and writings of master artists as an attempt to illuminate the intimate exchange between artist, medium, and creative source

La construction d’un tissage émotionnel au féminin dans la série Outlander

Avec quatre saisons diffusées et une cinquième en tournage, la série américano-britannique Outlander (Starz, 2014- ) représente un cas d’étude pertinent pour explorer la manière dont le format sériel donne à voir la cohérence du personnage. Créé par Ron Moore, le showrunner de Battlestar Galactica (Sci-Fi, 2003-2009), Outlander prête une attention toute particulière au réalisme émotionnel de ses personnages au sein d’un monde fictionnel marqué par la science-fiction et l’Histoire. Claire Beauchamp, jeune infirmière de la seconde guerre mondiale, se retrouve mystérieusement propulsée dans le contexte mouvementé de l’Ecosse jacobite. Le tissage émotionnel du personnage féminin se construit sur la durée de la série feuilletonesque où chaque épisode est différent et participe à l’étirement du personnage. Le corpus étudié comprend les deux premières saisons de la série ainsi que la première moitié de la saison 3 jusqu’aux retrouvailles du couple de Claire et Jamie après vingt ans de séparation (« A. Malcolm », épisode 305).Cet article entend démontrer comment l’adaptation sérielle permet à la fois de rationaliser un contenu très riche et parfois décousu et d’intensifier la narration pour mieux donner à voir les facettes du personnage. La série se prête d’autant plus à cette démonstration qu’elle débute comme une adaptation fidèle du matériau littéraire d’origine de Diana Gabaldon pour s’en émanciper peu à peu. L’adaptation sérielle se dote de motifs narratifs spécifiques pour dire l’authenticité du regard féminin de Claire comme le foyer narratif unique ou le female gaze. Il sera aussi intéressant de voir comment le tissage émotionnel de Claire se développe au sein de la matrice du couple notamment par le biais d’une conversation de l’absence. Enfin, la prise en compte du genre féminin du public de la série amènera à explorer la culture participative au féminin à l’heure des réseaux sociaux.With four seasons already broadcasted and a fifth one forthcoming, the American and British series Outlander (Starz, 2014-) is a relevant case study to explore the way the series format manifests the coherence of the character. Created by Ron Moore, the showrunner of Battlestar Galactica, Outlander is effectively paying attention to the emotional realism of its characters in a fictional world that is marked by science fiction and History. Claire Beauchamp, a young nurse from World War II, mysteriously finds herself thrown into the tense historical realm of Jacobite Scotland. The woman’s emotional weaving is being built in the long run in a series where each episode is different and contributes to the character’s enrichment. The corpus under study is composed of the first two seasons and the first half of season 3 until the reunion of Claire and Jamie Fraser after a twenty-year separation (« A.Malcolm », episode 305).In this article we intend to demonstrate how the series manages to make visible many aspects of the character by rationalizing a rich and somewhat rambling content and intensifying the storytelling at the same time. The series is all the more suitable to such a demonstration since it starts like a faithful adaptation of the original book from Diana Gabaldon and progressively emancipates itself. The series endows itself with specific narrative motifs to convey the authenticity of Claire’s female gaze. It will also be interesting to see how Claire’s emotional weaving is being developed within the couple’s matrix especially through the “conversation of absence”. Finally, taking into account the feminine gender of the series’ audience will lead to an exploration of the woman’s participatory culture in the era of digital social networking

An Evaluation of the Impact of Social and Structural Determinants of Health on Forgone Care during the COVID-19 Pandemic in Baltimore, Maryland

The Coronavirus 2019 (COVID-19) pandemic led to widespread disruptions in healthcare utilization. This included forgone care, defined as someone who perceives a need for healthcare but does not receive it. These disruptions exacerbated the morbidity and mortality associated with the pandemic and disproportionately impacted those who experience inequities across the social and structural determinants of health (SSDoH). Existing literature on the impacts of the pandemic on healthcare utilization predominately describe outpatient and hospital trends. However, very few studies have captured patient-reported forgone care. The purpose of this dissertation was to investigate the impacts of the COVID-19 pandemic on healthcare access and utilization by specifically looking at forgone chronic and preventive care, emergent care, and elective and dental procedures among adults living in Baltimore, MD. Cross-sectional survey data were abstracted from two parent studies that used different, yet complimentary sampling strategies that increased representation of minoritized and under-resourced populations. The resulting combined analytic sample provided a platform to explore forgone care within one urban city that has historically suffered from systemic and structural racism, leading to widespread disparities across the SSDoH. Several cross-cutting themes emerged as important considerations in this exploration of forgone care during the COVID-19 pandemic. First, individuals experiencing housing instability had higher rates and odds of forgone care when comparing those who reported not experiencing housing instability. Second, under-resourced and marginalized individuals who require frequent engagement with the health system suffered higher rates and odds of forgone care. Third, the correlates of forgone care are likely indicative of existing health disparities. Finally, community-level determinants of health were found not to account for forgone care, above and beyond individual-level factors. Understanding the overall rate of forgone care during the COVID-19 pandemic and its intersections with the SSDoH provides a more comprehensive view of the health impacts of the pandemic. It can also inform the development of models of care that can help dismantle systems that perpetuate inequities across the SSDoH and that can be leveraged during future public health emergencies to maintain individual and community health

NITROGEN CYCLING IN A FOREST STREAM DETERMINED BY A 15N TRACER ADDITION

Nitrogen uptake and cycling was examined using a six‐week tracer addition of 15N‐labeled ammonium in early spring in Walker Branch, a first‐order deciduous forest stream in eastern Tennessee. Prior to the 15N addition, standing stocks of N were determined for the major biomass compartments. During and after the addition, 15N was measured in water and in dominant biomass compartments upstream and at several locations downstream. Residence time of ammonium in stream water (5–6 min) and ammonium uptake lengths (23–27 m) were short and relatively constant during the addition. Uptake rates of NH4 were more variable, ranging from 22 to 37 μg N·m−2·min−1 and varying directly with changes in streamwater ammonium concentration (2.7–6.7 μg/L). The highest rates of ammonium uptake per unit area were by the liverwort Porella pinnata, decomposing leaves, and fine benthic organic matter (FBOM), although epilithon had the highest N uptake per unit biomass N. Nitrification rates and nitrate uptake lengths and rates were determined by fitting a nitrification/nitrate uptake model to the longitudinal profiles of 15N‐NO3 flux. Nitrification was an important sink for ammonium in stream water, accounting for 19% of the total ammonium uptake rate. Nitrate production via coupled regeneration/nitrification of organic N was about one‐half as large as nitrification of streamwater ammonium. Nitrate uptake lengths were longer and more variable than those for ammonium, ranging from 101 m to infinity. Nitrate uptake rate varied from 0 to 29 μg·m−2·min−1 and was ∼1.6 times greater than assimilatory ammonium uptake rate early in the tracer addition. A sixfold decline in instream gross primary production rate resulting from a sharp decline in light level with leaf emergence had little effect on ammonium uptake rate but reduced nitrate uptake rate by nearly 70%. At the end of the addition, 64–79% of added 15N was accounted for, either in biomass within the 125‐m stream reach (33–48%) or as export of 15N‐NH4 (4%), 15N‐NO3 (23%), and fine particulate organic matter (4%) from the reach. Much of the 15N not accounted for was probably lost downstream as transport of particulate organic N during a storm midway through the experiment or as dissolved organic N produced within the reach. Turnover rates of a large portion of the 15N taken up by biomass compartments were high (0.04–0.08 per day), although a substantial portion of the 15N in Porella (34%), FBOM (21%), and decomposing wood (17%) at the end of the addition was retained 75 d later, indicating relatively long‐term retention of some N taken up from water. In total, our results showed that ammonium retention and nitrification rates were high in Walker Branch, and that the downstream loss of N was primarily as nitrate and was controlled largely by nitrification, assimilatory demand for N, and availability of ammonium to meet that demand. Our results are consistent with recent 15N tracer experiments in N‐deficient forest soils that showed high rates of nitrification and the importance of nitrate uptake in regulating losses of N. Together these studies demonstrate the importance of 15N tracer experiments for improving our understanding of the complex processes controlling N cycling and loss in ecosystems