Summary and recommendations on nuclear electric propulsion technology for the space exploration initiative

A project in Nuclear Electric Propulsion (NEP) technology is being established to develop the NEP technologies needed for advanced propulsion systems. A paced approach has been suggested which calls for progressive development of NEP component and subsystem level technologies. This approach will lead to major facility testing to achieve TRL-5 for megawatt NEP for SEI mission applications. This approach is designed to validate NEP power and propulsion technologies from kilowatt class to megawatt class ratings. Such a paced approach would have the benefit of achieving the development, testing, and flight of NEP systems in an evolutionary manner. This approach may also have the additional benefit of synergistic application with SEI extraterrestrial surface nuclear power applications

Mass casualty events: what to do as the dust settles?

Care during mass casualty events (MCE) has improved during the last 15 years. Military and civilian collaboration has led to partnerships which augment the response to MCE. Much has been written about strategies to deliver care during an MCE, but there is little about how to transition back to normal operations after an event. A panel discussion entitled The Day(s) After: Lessons Learned from Trauma Team Management in the Aftermath of an Unexpected Mass Casualty Event at the 76th Annual American Association for the Surgery of Trauma meeting on September 13, 2017 brought together a cadre of military and civilian surgeons with experience in MCEs. The events described were the First Battle of Mogadishu (1993), the Second Battle of Fallujah (2004), the Bagram Detention Center Rocket Attack (2014), the Boston Marathon Bombing (2013), the Asiana Flight 214 Plane Crash (2013), the Baltimore Riots (2015), and the Orlando Pulse Night Club Shooting (2016). This article focuses on the lessons learned from military and civilian surgeons in the days after MCEs

Factors affecting B/Ca ratios in synthetic aragonite

Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here for personal use, not for redistribution. The definitive version was published in Chemical Geology 437 (2016): 67-76, doi:10.1016/j.chemgeo.2016.05.007.Measurements of B/Ca ratios in marine carbonates have been suggested to record seawater carbonate chemistry, however experimental calibration of such proxies based on inorganic partitioning remains limited. Here we conducted a series of synthetic aragonite precipitation experiments to evaluate the factors influencing the partitioning of B/Ca between aragonite and seawater. Our results indicate that the B/Ca ratio of synthetic aragonites depends primarily on the relative concentrations of borate and carbonate ions in the solution from which the aragonite precipitates; not on bicarbonate concentration as has been previously suggested. The influence of temperature was not significant over the range investigated (20 – 40°C), however, partitioning may be influenced by saturation state (and/or growth rate). Based on our experimental results, we suggest that aragonite B/Ca ratios can be utilized as a proxy of [CO32-]. Boron isotopic composition (δ11B) is an established pH proxy, thus B/Ca and δ11B together allow the full carbonate chemistry of the solution from which the aragonite precipitated to be calculated. To the extent that aragonite precipitation by marine organisms is affected by seawater chemistry, B/Ca may also prove useful in reconstructing seawater chemistry. A simplified boron purification protocol based on amberlite resin and the organic buffer TRIS is also described.This work was supported by the Australian Research Council (ARC) Centre of Excellence for Coral Reef Studies. Research conducted at WHOI was supported by NSF grant OCE-1338320. M.H. was supported by an ARC Super Science Fellowship and an NSF International Postdoctoral Fellowship. T.D. was supported by a NSF Graduate Research Fellowship. M.M. was supported by a Western Australian Premiers Fellowship and an ARC Laureate Fellowship

Coral calcification : insights from inorganic experiments and coral responses to environmental variables

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2010Coral calcification is examined using a laboratory model and living corals. In the laboratory model, abiogenic aragonite formed at high saturation state (Ω>~20) had a granular appearance and was enriched in trace elements, similar to centers of calcification and dark bands in corals. Abiogenic aragonite formed fibrous crystals at lower saturation states, similar to crystals which radiate out from centers of calcification. These similarities suggest the calcifying environment of the coral experiences a range of saturation states. To estimate when high or low saturation states occur within the coral, living corals were stained, staining patterns suggest dark bands form between dusk and dawn. A model is proposed in which daytime saturation state is limited by the availability of CO2. To test the potential for photosynthesis to limit CO2 availability to calcification, corals were grown under altered CO2 and nutrient levels. Elevated CO2 levels decreased calcification in zooxanthellate corals, however addition of nutrients reduced the negative impact of CO2. This suggests nutrient availability may limit photosynthesis under elevated pCO2 conditions. The effects of nutrients, CO2, and temperature were further tested on both zooxanthellate and azooxanthellate coral colonies. Unexpectedly, a gender difference was found in the effect of CO2 on calcification.Funding for this research was provided by a National Science Foundation Graduate Research Fellowship, Academic programs, a MIT Presidential Fellowship, WHOI Interdisciplinary Award #39040300, a WHOI Coastal Ocean Institute Award, the WHOI Ocean Life Institute, National Science Foundation grant #OCE-0648157, a Lizard Island Doctoral Fellowship, and an International Society for Reef Studies/Ocean Conservancy Doctoral Fellowship

Electrophysiological Dissociation of Picture Versus Word Encoding: The Distinctiveness Heuristic as a Retrieval Orientation

Event-related potentials (ERPs) were used to investigate the neural processes underlying the distinctiveness heuristic— a response mode in which participants expect to remember vivid details of an experience and make recognition decisions based on this metacognitive expectation. One group of participants studied pictures and auditory words; another group studied visual and auditory words. Studied and novel items were presented at test as words only, with all novel items repeating after varying lags. ERP differences were seen between the word and picture groups for both studied and novel items. For the novel items, ERP differences were largest in frontal and central midline electrodes. In separate analyses, the picture group showed the greatest ERP differences between item types in a parietally based component from 550 to 1000 msec, whereas the word group showed the greatest differences in a frontally based component from 1000 to 2000 msec. The authors suggest that the distinctiveness heuristic is a retrieval orientation that facilitates reliance upon recollection to differentiate between item types. Although the picture group can use this heuristic and its retrieval orientation on the basis of recollection, the word group must engage additional postretrieval processes to distinguish between item types, reflecting the use of a different retrieval orientation.Psycholog

Demise of the FAA\u27s Contract of Employment Exception - Gilmer v. Interstate/Johnson Lane Corp., The

The recent trend in the federal courts is to expand the scope of the Federal Arbitration Act2 (FAA) to include statutory claims. 3 Gilmer v. Interstate/Johnson Lane Corp. illustrates this trend by compelling claims under the Age Discrimination in Employment Act of 19674 (ADEA) to arbitration pursuant to an arbitration clause in an employment contract\u27 But does this trend neglect the rights of the individual employee vis-a-vis his employer and does it undermine the purpose of the contract of employment exception in the FAA?\u27 This Note will examine the Gilmer case and its adherence to the current trend of expanding the scope of the FAA in the area of statutory claims and also its refusal to address the issue of the contract of employment exception and to whom it should apply

On the geometry and topology of moduli spaces of multi-polygonal linkages

The geometric, topological, and symplectic properties of moduli spaces (spaces of configurations modulo rotations and translations) of polygonal linkages have been studied by Kapovich, Millson, and Kamiyama, et. al. One can form a polygonal linkage by taking two free linkages and identifying initial and terminal vertices. This can be generalized so that one takes three free linkages and identifies initial and terminal vertices. Then one obtains a linkage which contains multiple polygons, any two of which have shared edges. The geometric and topological properties of moduli spaces of these multi-polygonal linkages are studied. These spaces turn out to be compact algebraic varieties. Multi-quadrilateral linkages whose moduli spaces are at most one dimensional are classified. The dimensions and some Euler characteristics are computed, and conditions under which these spaces are smooth manifolds are determined. Some conditions are also given for when the moduli spaces are connected and when they are disjoint unions of two moduli spaces of polygonal linkages