Modeling and Testing of Non-Nuclear, Highpower Simulated Nuclear Thermal Rocket Reactor Elements

When the President offered his new vision for space exploration in January of 2004, he said, "Our third goal is to return to the moon by 2020, as the launching point for missions beyond," and, "With the experience and knowledge gained on the moon, we will then be ready to take the next steps of space exploration: human missions to Mars and to worlds beyond." A human mission to Mars implies the need to move large payloads as rapidly as possible, in an efficient and cost-effective manner. Furthermore, with the scientific advancements possible with Project Prometheus and its Jupiter Icy Moons Orbiter (JIMO), (these use electric propulsion), there is a renewed interest in deep space exploration propulsion systems. According to many mission analyses, nuclear thermal propulsion (NTP), with its relatively high thrust and high specific impulse, is a serious candidate for such missions. Nuclear rockets utilize fission energy to heat a reactor core to very high temperatures. Hydrogen gas flowing through the core then becomes superheated and exits the engine at very high exhaust velocities. The combination of temperature and low molecular weight results in an engine with specific impulses above 900 seconds. This is almost twice the performance of the LOX/LH2 space shuttle engines, and the impact of this performance would be to reduce the trip time of a manned Mars mission from the 2.5 years, possible with chemical engines, to about 12-14 months

Abating Prejudice With Presence: Dispositional Mindfulness Increases Interracial Helping Behavior

Helping behavior is less frequently shown toward members of social out-groups (Cikra, Bruneau, & Saxe, 2011). Race defines a common source of social division in America and other countries, and although most condemn racial discrimination, helping is undermined in interracial interactions (Saucier, Miller, & Doucet, 2005). Recent theory suggests that mindfulness, a receptive attention to one’s present experience, can attenuate the conceptual boundaries that typically separate and distance oneself from others (Trautwein, Schmidt, & Naranjo, 2014). We designed an experiment to examine whether dispositional mindfulness would be associated with increased helping behavior in interracial contexts. Self-identifying White participants (N = 139) witnessed a confederate in need of help while waiting to participate in a study, and experimenters observed whether participants helped them or not; self-identifying White or Black confederates were randomly assigned to each experimental session. Three-block sequential logistic regression models were constructed to identify predictors of same-race and interracial helping. Overall, dispositional mindfulness, agreeableness, and lower racial prejudice predicted greater helping behavior in same-race interactions (all ps \u3c 0.05). Interestingly, mindfulness moderated the help-reducing effects of racial prejudice in the interracial interactions (p \u3c 0.05). More specifically, high mindfulness was associated with increased helping behavior among those high in racial prejudice. This correlational evidence is consistent with mindfulness theory, which suggests deploying mindful attention dampens psychological barriers between self and others. This study highlights the potential for mindfulness in reducing defensive attitudes and increasing prosocial responsiveness across social lines.https://scholarscompass.vcu.edu/uresposters/1230/thumbnail.jp

A Preliminary Study on Expanding and Financing State Water Development

The effects of recent energy price increases, domestic inflation rates, financial market fluctuations, and changing public attitudes toward federally sponsored water resource development and management have brought economic and financial consideratiosn to the forefront of Western water management issues. Recently enacted federal policies place increased responsibility on the states and localities for the development and management of their water resources. A response common to many of the western states has been to stengthen traditional, and often small, water financing and development programs. In creating and sustaining such a posture, however, state governments must address the important questions pertaining to the economic and financial impact of greater state involvement, the distributional impacts of state taxing and lending programs, and the state social goals relating to such managerial involvement. The traditional and recently expanded water development programs of the State of Utah have been reviewed in the light of such management issues. The demand for state financing of water projects was addressed through an examination of economic indicators and an inventory of potential projects. State options for obtaining capital financing also were examined. This review indicates taht increased financing activity and the potential for increased concentration of water development project benefits to specific social groups have created a need for greater clarity in the legislative mandate and greater accounting and visibility of water project impacts through the use of improved economic and social evalution procedures. Moreover, in the absence of such safeguards, the continued investment of state funds might be considered premature and not always in the best interest of the state\u27s residents

Microclimate Effects on the Temporal/Spatial Distribution of Beef Cows Grazing Cool-Season Grass Pastures by Different Management Practices

Presence of cattle near pasture streams may increase the probability of bare ground and feces on streambanks and increase the risks of sediment, phosphorus, and fecal pathogen loading of water resources through direct deposition or transport in precipitation runoff. Management techniques such as providing off-stream water sources or managing cattle access to pasture streams through rotational stocking or use of stabilized stream access sites may limit the amount of time that the cattle spend near the stream, decreasing the risks of non-point source pollution. Six 30- acre cool-season grass pastures, bisected by a stream, were split into two blocks with three treatments per block. Treatments were: continuous stocking with unrestricted stream access (CSU), continuous stocking with access to the stream restricted to a 16-foot wide stabilized stream crossing (CSR), and rotational stocking (RS). Each pasture was stocked with 15 fall-calving Angus cows. For two weeks in each month from May through September, at least one cow in each pasture was fitted with a GPS collar programmed to record cow position at 10 minute intervals. Off-stream water was made available to cows in pastures with the CSU and CSR treatments for one week of the twoweek position measurement period in each month., Each pasture was divided into four zones to analyze position data; in the stream or on the streambank (stream zone), 0 to 110 feet from the streambank (110 zone), 110 to 220 feet from the streambank (220 zone), and greater than 220 feet from the streambank (upland zone). The combination of the stream and 110 zones were defined as the streamside zone. Cattle in both RS and CSR pastures spent (P \u3c 0.10) less time within the stream and 110 zones than CSU pastures in June and May, and July, respectively. Off-stream water availability had no meaningful effect on cattle distribution in the CSU and CSR pastures. With increasing temperatures, the probability that cattle were present in the streamside zone of CSU pastures increased more rapidly than CSR pastures

The product field of values

For two n-by-n matrices, A, B, the product field of values is the set P(A, B) = {\u3c AX, X \u3e \u3c Bx, X \u3e : X is an element of C-n, parallel to X parallel to = 1}. In this paper, we establish basic properties of the product field of values. The main results are a proof that the product field is a simply connected subset of the complex plane and a characterization of matrix pairs for which the product field has nonempty interior. (C) 2012 Elsevier Inc. All rights reserved

Promoting Prosocial Responsiveness across Racial Divides through Mindfulness

In interracial and other intergroup interactions, prosocial emotions and actions are often undermined (Cikara & van Bavel, 2014). Perceiving psychological separateness between “us” and “them” – which is often an automatic, unintentional process – is psychological kindling for lower prosocial responsiveness that leads to prejudice, discrimination, aggressive conflict (Cikara, 2015). Recent research has shown that mindfulness, an open and unconditional attention to one’s present experiences, is associated with decreased automaticity and racial bias (Kang, Gruber, & Gray, 2013; Lueke & Gibson, 2014), barriers that hinder prosocial responsiveness (Trautwien, Schmidt, & Naranjo, 2014). Two experiments investigated whether brief mindfulness training promoted prosocial responsiveness toward an ostracized person of another race. Before witnessing a person of another race being excluded in an online ball-tossing game (Cyberball), participants in both studies were randomized to either an audio-recorded mindfulness training (MT), a structurally-equivalent attention control training (CT), or a no instruction control (NT). MI participants in Study 1 (N=124) showed trends towards higher empathic concern (p=.065), while MI participants in Study 2 (N=131) reported higher empathic concern for the excluded player (p\u3c0.05). MI participants in both studies wrote more comforting emails to them (p\u3c0.01), as coded for prosociality (c.f., Masten et al., 2011). Only in Study 2 did MI participants passed the ball more to the victim in an ‘all play’ game (p\u3c.05), presumably because their identity was less “known” than in Study 1; specifically, players’ photo images were loaded into the game in Study 1, but only first names were shared in Study 2. These studies underscore the potential for mindfulness training to foster sensitive attitudes across social and cultural lines within increasingly growing anonymous (i.e., online) contexts.https://scholarscompass.vcu.edu/uresposters/1222/thumbnail.jp

Organizational Alternatives to Achieve Greater Uniformity in State-wide Water Rights Management in Utah

In the distribution of water among users in the state of Utah there is lack of organizational uniformity. On some rivers, the state engineer is assisted by river sommissioners who have been appointed to measure and monitor water deliveries. On other rivers there are no comissioners; problems and disputes must be settled on a case by case basis by the state engineer. The responsibilities, arrangements, salaries, and methods of payment for commissioners vary from basin to basin. A more unifed distribution organization composed of state-employed water sommissioners would have several advantages over the existing system of commissioners employed by local water users. Advantages would include the development and retantion of a higher level of expertise, improved record keeping and reporting, more complete geographical coverage of river systems, and better balance of commissioner work loads. These advantages would come at a higher cost, but the impact on water users could be mitigated by dividing the cost of the system between the users and the general public in a dual financing arrangement

How do lizard niches conserve, diverge or converge? Further exploration of saurian evolutionary ecology

Background: Environmental conditions on Earth are repeated in non-random patterns that often coincide with species from different regions and time periods having consistent combinations of morphological, physiological and behavioral traits. Observation of repeated trait combinations among species confronting similar environmental conditions suggest that adaptive trait combinations are constrained by functional tradeoffs within or across niche dimensions. In an earlier study, we assembled a high-resolution database of functional traits for 134 lizard species to explore ecological diversification in relation to five fundamental niche dimensions. Here we expand and further examine multivariate relationships in that dataset to assess the relative influence of niche dimensions on the distribution of species in 6-dimensional niche space and how these may deviate from distributions generated from null models. We then analyzed a dataset with lower functional-trait resolution for 1023 lizard species that was compiled from our dataset and a published database, representing most of the extant families and environmental conditions occupied by lizards globally. Ordinations from multivariate analysis were compared with null models to assess how ecological and historical factors have resulted in the conservation, divergence or convergence of lizard niches. Results: Lizard species clustered within a functional niche volume influenced mostly by functional traits associated with diet, activity, and habitat/substrate. Consistent patterns of trait combinations within and among niche dimensions yielded 24 functional groups that occupied a total niche space significantly smaller than plausible spaces projected by null models. Null model tests indicated that several functional groups are strongly constrained by phylogeny, such as nocturnality in the Gekkota and the secondarily acquired sit-and-wait foraging strategy in Iguania. Most of the widely distributed and species-rich families contained multiple functional groups thereby contributing to high incidence of niche convergence. Conclusions: Comparison of empirical patterns with those generated by null models suggests that ecological filters promote limited sets of trait combinations, especially where similar conditions occur, reflecting both niche convergence and conservatism. Widespread patterns of niche convergence following ancestral niche diversification support the idea that lizard niches are defined by trait-function relationships and interactions with environment that are, to some degree, predictable and independent of phylogeny.Fil: Pelegrin, Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Winemiller, Kirk Owen. Texas A&M University; Estados UnidosFil: Vitt, Laurie J.. University Of Oklahoma; Estados UnidosFil: Fitzgerald, Daniel B.. United States Geological Survey; Estados UnidosFil: Pianka, Eric R. University of Texas at Austin; Estados Unido