Some neglected axioms in fair division

Conditions one might impose on fair allocation procedures are introduced. Nondiscrimination requires that agents share an item in proportion to their entitlements if they receive nothing else. The "price" procedures of Pratt (2007), including the Nash bargaining procedure, satisfy this. Other prominent efficient procedures do not. In two-agent problems, reducing the feasible set between the solution and one agent's maximum point increases the utility cost to that agent of providing any given utility gain to the other and is equivalent to decreasing the dispersion of the latter's values for the items he does not receive without changing their total. One-agent monotonnicity requires that such a change should not hurt the first agent, limited monotonicity that the solution should not change. For prices, the former implies convexity in the smaller of the two valuations, the latter linearity. In either case, the price is at least their average and hence spiteful.Fair division, efficient allocation, nondiscrimination axiom, monotonicity axioms, envy-free, spite, bargaining solutions.

Personal Pedagogical Systems: Core Beliefs, Foundational Knowledge, and Informal Theories of Teaching

This case study describes a personal pedagogical system that acts a guide for adult educators in their practice. The system reflects core beliefs (assumptions about truth or propriety), foundational knowledge (essential knowledge for effective teaching of adults) and an informal theory of teaching (a theory of what works and what doesn\u27t work), all of which interact dialectically. Implications for further research and practice are discussed

The Ultraviolet Detection of Diffuse Gas in Galaxy Groups

A small survey of the UV-absorbing gas in 12 low-$z$ galaxy groups has been conducted using the Cosmic Origins Spectrograph (COS) on-board the Hubble Space Telescope (HST). Targets were selected from a large, homogeneously-selected sample of groups found in the Sloan Digital Sky Survey (SDSS). A critical selection criterion excluded sight lines that pass close ($<1.5$ virial radii) to a group galaxy, to ensure absorber association with the group as a whole. Deeper galaxy redshift observations are used both to search for closer galaxies and also to characterize these $10^{13.5}$ to $10^{14.5} M_{\odot}$ groups, the most massive of which are highly-virialized with numerous early-type galaxies (ETGs). This sample also includes two spiral-rich groups, not yet fully-virialized. At group-centric impact parameters of 0.3-2 Mpc, these $\mathrm{S/N}=15$-30 spectra detected HI absorption in 7 of 12 groups; high (OVI) and low (SiIII) ion metal lines are present in 2/3 of the absorption components. None of the three most highly-virialized, ETG-dominated groups are detected in absorption. Covering fractions $\gtrsim50$% are seen at all impact parameters probed, but do not require large filling factors despite an enormous extent. Unlike halo clouds in individual galaxies, group absorbers have radial velocities which are too low to escape the group potential well without doubt. This suggests that these groups are "closed boxes" for galactic evolution in the current epoch. Evidence is presented that the cool and warm group absorbers are not a pervasive intra-group medium (IGrM), requiring a hotter ($T\sim10^6$ to $10^7$ K) IGrM to be present to close the baryon accounting.Comment: Resubmitted to ApJS after first review; 82 pages (27 for main text, rest are Appendices and supplemental figures and tables), 47 figures, 21 table

Development and Testing of a High Stability Engine Control (HISTEC) System

Flight tests were recently completed to demonstrate an inlet-distortion-tolerant engine control system. These flight tests were part of NASA's High Stability Engine Control (HISTEC) program. The objective of the HISTEC program was to design, develop, and flight demonstrate an advanced integrated engine control system that uses measurement-based, real-time estimates of inlet airflow distortion to enhance engine stability. With improved stability and tolerance of inlet airflow distortion, future engine designs may benefit from a reduction in design stall-margin requirements and enhanced reliability, with a corresponding increase in performance and decrease in fuel consumption. This paper describes the HISTEC methodology, presents an aircraft test bed description (including HISTEC-specific modifications) and verification and validation ground tests. Additionally, flight test safety considerations, test plan and technique design and approach, and flight operations are addressed. Some illustrative results are presented to demonstrate the type of analysis and results produced from the flight test program

Optimization of chemoenzymatic mass-tagging by strain-promoted cycloaddition (SPAAC) for the determination of O-GlcNAc stoichiometry by Western blotting

The dynamic modification of intracellular proteins by O-linked β-N-acetylglucosamine (O-GlcNAcylation) plays critical roles in many cellular processes. Although various methods have been developed for O-GlcNAc detection, there are few techniques for monitoring glycosylation stoichiometry and state (i.e., mono-, di-, etc., O-GlcNAcylated). Measuring the levels of O-GlcNAcylation on a given substrate protein is important for understanding the biology of this critical modification and for prioritizing substrates for functional studies. One powerful solution to this limitation involves the chemoenzymatic installation of polyethylene glycol polymers of defined molecular mass onto O-GlcNAcylated proteins. These “mass tags” produce shifts in protein migration during sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) that can be detected by Western blotting. Broad adoption of this method by the scientific community has been limited, however, by a lack of commercially available reagents and well-defined protein standards. Here, we develop a “click chemistry” approach to this method using entirely commercial reagents and confirm the accuracy of the approach using a semisynthetic O-GlcNAcylated protein. Our studies establish a new, expedited experimental workflow and standardized methods that can be readily utilized by non-experts to quantify the O-GlcNAc stoichiometry and state on endogenous proteins in any cell or tissue lysate

A Study of the Sediments of Narragansett Bay, Volume 1: The Surface Sediments of Narragansett Bay

This report is divided into two volumes. The focus of Volume I is the surface sediments of Narragansett Bay. Volume I contains a study of the surface sediments of Narragansett Bay (Chapter 1), a study of suspended sediments in the northwestern section of the Narragansett Bay System (Chapter 2), a study of the relationship between contaminant concentrations in the surface sediments and soft tissues of the hard clam, Mercenaria mercenaria in Narragansett Bay (Chapter 3), and the results of a side-scan sonar survey of the Providence River dredged channel (Chapter 4). The focus of Volume II is a study of sediment cores from the Narragansett Bay System. Chapter 5 contains the results of geophysical (side-scan and sub-bottom sonar) that support the core studies. The results of studies of sediment cores from Narragansett Bay are contained in Chapter 6, and the results of sediment core studies from its freshwater tributaries (i.e., the Blackstone and Pawtuxet Rivers) are contained in Chapter 7. (Text taken from report preface