24,059 research outputs found
Analysis of nuclear waste disposal in space, phase 3. Volume 2: Technical report
The options, reference definitions and/or requirements currently envisioned for the total nuclear waste disposal in space mission are summarized. The waste form evaluation and selection process is documented along with the physical characteristics of the iron nickel-base cermet matrix chosen for disposal of commercial and defense wastes. Safety aspects of radioisotope thermal generators, the general purpose heat source, and the Lewis Research Center concept for space disposal are assessed as well as the on-pad catastrophic accident environments for the uprated space shuttle and the heavy lift launch vehicle. The radionuclides that contribute most to long-term risk of terrestrial disposal were determined and the effects of resuspension of fallout particles from an accidental release of waste material were studied. Health effects are considered. Payload breakup and rescue technology are discussed as well as expected requirements for licensing, supporting research and technology, and safety testing
Analysis of nuclear waste disposal in space, phase 3. Volume 1: Executive summary of technical report
The objectives, approach, assumptions, and limitations of a study of nuclear waste disposal in space are discussed with emphasis on the following: (1) payload characterization; (2) safety assessment; (3) health effects assessment; (4) long-term risk assessment; and (5) program planning support to NASA and DOE. Conclusions are presented for each task
Investigation of infrared phonon modes in multiferroic single-crystal FeTeOBr
Reflection and transmission as a function of temperature (5--300 K) have been
measured on single crystals of the multiferroic compound FeTeOBr
utilizing light spanning the far infrared to the visible portions of the
electromagnetic spectrum. The complex dielectric function and optical
properties were obtained via Kramers-Kronig analysis and by fits to a
Drude-Lortentz model. Analysis of the anisotropic excitation spectra via
Drude-Lorentz fitting and lattice dynamical calculations have lead to the
observation of all 52 IR-active modes predicted in the plane and 43 or the
53 modes predicted along the b axis of the monoclinic cell. Assignments to
groups (clusters) of phonons have been made and trends within them are
discussed in light of our calculated displacement patterns.Comment: 9 pages, 7 figure
Recommended from our members
Fortification and health: challenges and opportunities.
Fortification is the process of adding nutrients or non-nutrient bioactive components to edible products (e.g., food, food constituents, or supplements). Fortification can be used to correct or prevent widespread nutrient intake shortfalls and associated deficiencies, to balance the total nutrient profile of a diet, to restore nutrients lost in processing, or to appeal to consumers looking to supplement their diet. Food fortification could be considered as a public health strategy to enhance nutrient intakes of a population. Over the past century, fortification has been effective at reducing the risk of nutrient deficiency diseases such as beriberi, goiter, pellagra, and rickets. However, the world today is very different from when fortification emerged in the 1920s. Although early fortification programs were designed to eliminate deficiency diseases, current fortification programs are based on low dietary intakes rather than a diagnosable condition. Moving forward, we must be diligent in our approach to achieving effective and responsible fortification practices and policies, including responsible marketing of fortified products. Fortification must be applied prudently, its effects monitored diligently, and the public informed effectively about its benefits through consumer education efforts. Clear lines of authority for establishing fortification guidelines should be developed and should take into account changing population demographics, changes in the food supply, and advances in technology. This article is a summary of a symposium presented at the ASN Scientific Sessions and Annual Meeting at Experimental Biology 2014 on current issues involving fortification focusing primarily on the United States and Canada and recommendations for the development of responsible fortification practices to ensure their safety and effectiveness
Geoacoustic Inversion of Ship Radiated Noise in Shallow Water Using Data From a Single Hydrophone
The Centre for Maritime Research and Experimentation conducted a geoacoustic inverse experiment in the Mediterranean Sea in the summer of 2012. Among the objectives was to employ an autono- mous underwater vehicle to collect acoustic data to invert for properties of the seafloor. Inversion results for the compression wave speed in the bottom and the source spectrum of the R/V Alliance during a close approach to the bottom moored vehicle are presented. The estimated wave speed was 1529 m/s (r ¼ 10). The source spectrum of the Alliance was estimated across more than six octaves of frequency
Leading from the Center Out: The Joint Library Services Leadership Team at James Madison University
In a system with multiple service points, how can leadership work together to keep the library as a whole relevant and central to students? James Madison University Libraries created the Joint Library Services Leadership Team, which works outside traditional departmental silos to provide coherent, consistent, and collaborative services regardless of location.
Three major service points of James Madison University Libraries, the two main library circulation/reference departments and the media resources center, have historically been both physically and philosophically separate from each other. Although the departments shared common goals of providing excellent student learning-focused services, they did not systematically work together to do so. Library hierarchical structures placed each department parallel to the others, with limited connections across leadership levels.
As a result, each created unique services and outreach and competed in planning and budgeting processes. When collaboration across the departments happened, it was often project based, convenient, personality driven, and an extra duty on top of regular job expectations. Some excellent service programs came out of these ad hoc collaborations, including the development of core competencies for circulation services, joint training events, and the development of and training on procedures for emergency response.
This competitive model did not help the libraries fulfill the goal of providing student learning-focused services that are consistent, cohesive, and collaborative across locations and departments. After much debate, and some changes in personnel, the leadership of the three departments reworked the parallel department model to place collaboration in service planning and deployment at the center, with departmental hierarchies radiating out in rings.
This allows for collaboration to be thoughtful, deliberate, intentional, position driven, and included in job expectations at all levels. While the departments are still physically separated, the philosophical differences melt away, allowing for joint services and outreach, and shared planning and budgeting. It is the experience – and the continuing hope – of the JLSL Team that this model allows the three departments to lead from the center out ensures that we put our services and outreach for our students, and their academic, civic, and cultural lives, at the center of our concerns
Nutritional Quality of Leaves and Unripe Fruit Consumed as Famine Foods by the Flying Foxes of Samoa
Many tropical herbivores alter their diets throughout the year in
response to different levels of food availability. Fruit bats, including Pteropus
samoensis Peale and Pteropus tonganus Quoy & Gaimard, are phytophagous
species that may increase their consumption of foods such as unripe fruit and
leaves in periods of low fruit diversity and volume. These periods include the
tropical dry season or following the frequent hurricanes that batter the Samoan
Archipelago. We examined the nutritional composition of leaves and immature
fruits and compared the levels of organic and mineral nutrients with those of
ripe fruit. We used principal components analysis (PCA) to examine patterns
of variation in nutrient components of leaves, unripe fruit, and ripe fruit, as
well as to compare the mean levels of nutrients. Overall, unripe fruit provided
levels of nutrients comparable with those of ripe fruit of the same species for
many organic and mineral components. Unripe fruit were only half as rich in
iron as ripe fruit, but unripe fruit had high levels of calcium compared with
ripe fruit of the same species. Leaves are often cited as a rich source of protein
for fruit bats, and our results were consistent with this suggestion. Leaves were
also found to be rich in zinc, manganese, and calcium. Therefore, flying foxes
and other herbivores probably do not avoid unripe fruits and leaves because of
their low nutrient levels. It may be that these famine foods are not normally
consumed because of the presence of secondary compounds, low concentrations
of palatable sugars, or a distasteful and hard pericarp on unripe fruits
Alcohol-related adverse consequences: cross-cultural variations in attribution process among young adults
Background: Social norms around what is culturally accepted in terms of alcohol consumption and drunken comportment appear important regarding the acceptance of alcohol-related adverse consequences; however, investigations often neglect to consider differences in terms of attribution. This study aims at assessing cross-cultural differences in the reporting of alcohol-related adverse consequences. It also considers differences across consequences that might explain which type of consequences (mainly acute or mainly chronic) are most affected by an attribution process. Methods: Conditional regression models were estimated based on data from eight European countries participating in the Gender, Alcohol and Culture—An International Study (GENACIS) project. Cases were matched to controls based on usual drinking patterns in order to control for average volume of alcohol and frequency of ‘risky single occasion drinking' (RSOD). Results: Differences among the patterns of associations between countries and consequences were evident. The distinction between Nordic and other European countries was persistent. A higher variability of associations was observed for some consequences, namely the mainly acute instances. Finally, the Isle of Man and Switzerland showed specific trends with associations across consequences. Conclusion: Reporting of alcohol-related adverse consequences seemed strongly affected by cultural norms. The latter may be exemplified by viewing drinking as ‘time-out' behaviour. Respondents in countries with a stereotypical history of being ‘dry' or with a stereotyped ‘binge' drinking culture were more likely to attribute consequences to their alcohol consumption than people in ‘wet' countries. This was particularly true for consequences that related to episodic ‘time-out' heavy drinkin
- …