249 research outputs found
Rationalism, Capitalism, and Democracy: The Views of Schumpeter and Knight
The concept of rationality is both the origination point and the Achilles’ heel of the study of economic theory. Two of America’s more important economists, J. A. Schumpeter and Frank H. Knight, held highly developed views of the rationalistic civilization and rational thought. Although considerable concordance is present in their visions of rationality, conceptual differences exist.
Rational behavior is, in many respects, like beauty in that its meaning is defined by the extent to which there is a mapping with the values of the observer. Any discussion of rationality must begin with this difficult problem of relativity in values.
This paper begins, therefore, by identifying the definitions and origins of rationality according to Schumpeter and Knight. The paper then moves to an explication of the views Knight and Schumpeter held on rationality and the implications they perceived for capitalism and democracy
The Neglected Institutionalism of Schumpeter\u27s and Knight\u27s Views of Rationality
The concept of rationality is both the origination point and the Achilles\u27 heel of the study of human behavior in economics. The rationalist view of human nature is arguably the most pressing issue facing contemporary economics. Fields of knowledge other than economics have developed alternative theories of human activity to the neoclassical\u27s pure economic man. They include Abraham Maslow\u27s hierarchy of needs, Kenneth Boulding\u27s grants economy, and John Rawls\u27 original position doctrine. Within economics, the Institutionalists have been the leading critics of the assumption that behavior in the economic sphere is rationally directed.
A consensus view of rationality does not exist among Institutionalists. However, a synthesized Institutionalist conception of rationality would include the effects of culture, habit, social structure, and psychological makeup on individual and collective decisions. Additionally, an essential component of such a conceptualization would be the evolutionary aspect of rationalism, or how it develops throughout the life-process. These precepts are widely associated with the work of Thorstein Veblen and J. M. Clark
Plasma distribution in Mercury’s magnetosphere derived from MESSENGER Magnetometer and Fast Imaging Plasma Spectrometer observations
We assess the statistical spatial distribution of plasma in Mercury’s magnetosphere from observations of magnetic pressure deficits and plasma characteristics by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. The statistical distributions of proton flux and pressure were derived from 10 months of Fast Imaging Plasma Spectrometer (FIPS) observations obtained during the orbital phase of the MESSENGER mission. The Magnetometer-derived pressure distributions compare favorably with those deduced from the FIPS observations at locations where depressions in the magnetic field associated with the presence of enhanced plasma pressures are discernible in the Magnetometer data. The magnitudes of the magnetic pressure deficit and the plasma pressure agree on average, although the two measures of plasma pressure may deviate for individual events by as much as a factor of ~3. The FIPS distributions provide better statistics in regions where the plasma is more tenuous and reveal an enhanced plasma population near the magnetopause flanks resulting from direct entry of magnetosheath plasma into the low-latitude boundary layer of the magnetosphere. The plasma observations also exhibit a pronounced north-south asymmetry on the nightside, with markedly lower fluxes at low altitudes in the northern hemisphere than at higher altitudes in the south on the same field line. This asymmetry is consistent with particle loss to the southern hemisphere surface during bounce motion in Mercury’s offset dipole magnetic field
A Mercury Lander Mission Concept Study for the Next Decadal Survey
Mariner 10 provided our first closeup reconnaissance of Mercury during its three flybys in 1974 and 1975. MESSENGERs 20112015 orbital investigation enabled numerous discoveries, several of which led to substantial or complete changes in our fundamental understanding of the planet. Among these were the unanticipated, widespread presence of volatile elements (e.g., Na, K, S); a surface with extremely low Fe abundance whose darkening agent is likely C; a previously unknown landformhollows that may form by volatile sublimation from within rocks exposed to the harsh conditions on the surface; a history of expansive effusive and explosive volcanism; substantial radial contraction of the planet from interior cooling; offset of the dipole moment of the internal magnetic field northward from the geographic equator by ~20% of the planets radius; crustal magnetization, attributed at least in part to an ancient field; unexpected seasonal variability and relationships among exospheric species and processes; and the presence in permanently shadowed polar terrain of water ice and other volatile materials, likely to include complex organic compounds. Mercurys highly chemically reduced and unexpectedly volatile-rich composition is unique among the terrestrial planets and was not predicted by earlier hypotheses for the planets origin. As an end-member of terrestrial planet formation, Mercury holds unique clues about the original distribution of elements in the earliest stages of the Solar System and how planets (and exoplanets) form and evolve in close proximity to their host stars. The BepiColombo mission promises to expand our knowledge of this planet and to shed light on some of the mysteries revealed by the MESSENGER mission. However, several fundamental science questions raised by MESSENGERs pioneering exploration of Mercury can only be answered with in situ measurements from the planets surface
Standardized Direct Observation Assessment Tool: Using a Training Video.
BACKGROUND: We developed a DVD training tool to educate physicians evaluating emergency residents on accurate Standardized Direct Observation Assessment Tool (SDOT) application.
OBJECTIVE: Our goal was to assess whether this training video improved attendings\u27 and senior residents\u27 SDOT use.
METHODS: Participants voluntarily completed SDOT evaluations based on a scripted test video. A DVD with positive and negative scenarios of proper SDOT use was viewed. It included education on appropriate recording of 26 behaviors. The test scenario was viewed again and follow-up SDOTs submitted. Performances by attendings and residents on the pre- and post-test SDOTs were compared.
RESULTS: Twenty-six attendings and 26 senior residents participated. Prior SDOT experience was noted for 8 attendings and 11 residents. For 20 anchors, participants recorded observed behaviors with statistically significant difference on one each of the pretest (no. 20; p = 0.034) and post-test (no. 14; p = 0.041) SDOTs. On global competency assessments, pretest medical knowledge (p = 0.016) differed significantly between groups. The training intervention changed one anchor (no. 5; p = 0.035) and one global assessment (systems-based practice; p = 0.031) more negatively for residents. Recording SDOTs with exact agreement occurred 48.73% for attendings pretest and 54.41% post-test; resident scores were 45.86% and 49.55%, respectively. DVD exposure slightly raised attending scores (p = 0.289) and significantly lowered resident scores (p = 0.046).
CONCLUSIONS: Exposure to an independently developed SDOT training video tended to raise attending scores, though without significance, while at the same time lowered senior resident scores statistically significantly. Emergency attendings\u27 and senior residents\u27 SDOT scoring rarely differed with significance; about half of anchor behaviors were recorded with exact agreement. This suggests senior residents, with appropriate education, may participate in SDOT assessment
Interactions of the periplasmic binding protein CeuE with Fe(III) n-LICAM(4-) siderophore analogues of varied linker length
Bacteria use siderophores to mediate the transport of essential Fe(III) into the cell. In Campylobacter jejuni the periplasmic binding protein CeuE, an integral part of the Fe(III) transport system, has adapted to bind tetradentate siderophores using a His and a Tyr side chain to complete the Fe(III) coordination. A series of tetradentate siderophore mimics was synthesized in which the length of the linker between the two iron-binding catecholamide units was increased from four carbon atoms (4-LICAM(4-)) to five, six and eight (5-, 6-, 8-LICAM(4-), respectively). Co-crystal structures with CeuE showed that the inter-planar angles between the iron-binding catecholamide units in the 5-, 6- and 8-LICAM(4-) structures are very similar (111°, 110° and 110°) and allow for an optimum fit into the binding pocket of CeuE, the inter-planar angle in the structure of 4-LICAM(4-) is significantly smaller (97°) due to restrictions imposed by the shorter linker. Accordingly, the protein-binding affinity was found to be slightly higher for 5- compared to 4-LICAM(4-) but decreases for 6- and 8-LICAM(4-). The optimum linker length of five matches that present in natural siderophores such as enterobactin and azotochelin. Site-directed mutagenesis was used to investigate the relative importance of the Fe(III)-coordinating residues H227 and Y288
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Distribution and Compositional Variations of Plasma Ions in Mercury's Space Environment: The First Three Mercury Years of MESSENGER Variations
We have analyzed measurements of planetary ions near Mercury made by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) Fast Imaging Plasma Spectrometer (FIPS) over the first three Mercury years of orbital observations (25 March 2011 through 31 December 2011). We determined the composition and spatial distributions of the most abundant species in the regions sampled by the MESSENGER spacecraft during that period. In particular, we here focus on altitude dependence and relative abundances of species in a variety of spatial domains. We used observed density as a proxy for ambient plasma density, because of limitations to the FIPS field of view. We find that the average observed density is 3.9 × 10-2 cm-3 for He2+, 3.4 × 10-4 cm-3 for He+, 8.0 × 10-4 cm-3 for O+-group ions, and 5.1 × 10-3 cm-3 for Na+-group ions. Na+-group ions are particularly enhanced over other planetary ions (He+ and O+ group) in the northern magnetospheric cusp (by a factor of ~2.0) and in the premidnight sector on the nightside (by a factor of ~1.6). Within 30 degrees of the equator, the average densities of all planetary ions are depressed at the subsolar point relative to the dawn and dusk terminators. The effect is largest for Na+-group ions, which are 49% lower in density at the subsolar point than at the terminators. This depression could be an effect of the FIPS energy threshold. The three planetary ion species considered show distinct dependences on altitude and local time. The Na+ group has the smallest e-folding height at all dayside local times, whereas He+ has the largest. At the subsolar point, the e-folding height for Na+-group ions is 590 km, and that for the O+ group and He+ is 1100 km. On the nightside and within 750 km of the geographic equator, Na+-group ions are enhanced in the premidnight sector. This enhancement is consistent with nonadiabatic motion and may be observational evidence that nonadiabatic effects are important in Mercury's magnetosphere
MESSENGER Observations of Dipolarization Events in Mercury's Magnetotail
Several series of large dipolarization events are documented from magnetic field observations in Mercury's magnetotail made by the MESSENGER spacecraft. The dipolarizations are identified by a rapid (∼1 s) increase in the northward component of the magnetic field, followed by a slower return (∼10 s) to pre-onset values. The changes in field strength during an event frequently reach 40 nT or higher, equivalent to an increase in the total magnetic field magnitude by a factor of ∼4 or more. The presence of spatially constrained dipolarizations at Mercury provides a key to understanding the magnetic substorm process in a new parameter regime: the dipolarization timescale, which is shorter than at Earth, is suspected to lead to efficient non-adiabatic heating of the plasma sheet proton population, and the high recurrence rate of the structures is similar to that frequently observed for flux ropes and traveling compression regions in Mercury's magnetotail. The relatively short lifetime of the events is attributed to the lack of steady field-aligned current systems at Mercury
MESSENGER Observations of a Flux-Transfer-Event Shower at Mercury
Analysis of MESSENGER magnetic field observations taken in the southern lobe of Mercury's magnetotail and the adjacent magnetosheath on 11 April 2011 indicates that a total of 163 flux transfer events (FTEs) occurred within a 25 min interval. Each FTE had a duration of ∼2-3 s and was separated in time from the next by ∼8-10 s. A range of values have been reported at Earth, with mean values near ∼1-2 min and ∼8 min, respectively. We term these intervals of quasiperiodic flux transfer events "FTE showers." The northward and sunward orientation of the interplanetary magnetic field during this shower strongly suggests that the FTEs observed during this event formed just tailward of Mercury's southern magnetic cusp. The point of origin for the shower was confirmed with the Cooling model of FTE motion. Modeling of the individual FTE-type flux ropes in the magnetosheath indicates that these flux ropes had elliptical cross sections, a mean semimajor axis of 0.15RM (where RM is Mercury's radius, or 2440 km), and a mean axial magnetic flux of 1.25 MWb. The lobe magnetic field was relatively constant until the onset of the FTE shower, but thereafter the field magnitude decreased steadily until the spacecraft crossed the magnetopause. This decrease in magnetic field intensity is frequently observed during FTE showers. Such a decrease may be due to the diamagnetism of the new magnetosheath plasma being injected into the tail by the FTEs
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