3,148 research outputs found
Exploring site formation and building local contexts through wiggle-match radiocarbon dating: re-dating of the Firth of Clyde Crannogs, Scotland
There are at least four wooden intertidal platforms, also known as marine crannogs, in the Firth of Clyde, on the west coast of Scotland. The interpretation of these sites partly depends on their dating and, if coeval, they could point to the presence of a native maritime hub. Furthermore, the spatial coincidence with the terminus of the Antonine Wall has led to speculation about the role they may have played in Roman-native interaction during the occupation of southern Scotland in the early first millennium cal ad. Hence, a better absolute chronology is essential to evaluate whether the marine crannogs were contemporary with one another and whether they related to any known historic events. This article presents results of a wiggle-match dating project aimed at resolving these uncertainties at two of the sites in question, Dumbuck and Erskine Bridge crannogs. The results show that the construction of these sites pre-date direct Roman influence in Scotland. Furthermore, the results indicate that the two sites were built at least 300 years apart, forcing us to consider the possibility that they may have functioned in very different historical contexts. Other findings include technical observations on the fine shape of the radiocarbon calibration curve near the turn of the first millennia bc/ad and potential evidence for persistent contamination in decayed and exposed sections of waterlogged alder
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The Delicate Dance of Immersion and Insulation: The Politicization of the FDA Commissioner
The Food and Drug Administration never has been and never will be completely insulated from politics; it exists and operates as an integral part of the federal government in Washington, DC, not in a vacuum. Nevertheless, the FDA Commissioner has become a more political entity since 1988, the year in which Congress made the position subject to Senate confirmation. Whether considered beneficial or adverse, this politicization of FDA deserves examination—from the two decades preceding the 1988 Act, to the motivation behind the Act, to the Act itself, and through the present. This paper will endeavor to conduct such an examination
Au service de l'argumentation : le classement des figures chez Guillaume Tardif
Le Rhetoricae artis ac oratoriae facultatis compendium de Guillaume Tardif est la seconde rhétorique intégrale en langue latine à être publiée par un auteur français. Remaniée dans trois éditions postérieures, elle témoigne d'un intérêt profond pour la tradition oratoire et d'un désir pressant de l'adapter aux besoins contemporains. Tardif montre sa plus grande originalité dans le classement des figures : les divisant selon leur convenance aux différentes parties du discours, il essaie d'envisager le style en fonction du contenu, restaurant ainsi à la rhétorique son unité perdue. Cette ingénieuse tentative a été reprise par Pierre Fabri dans son Grand et Vray Art de pleine rhétorique (1521). L'influence de Tardif a cessé quand le travail de Fabri fut éclipsé dans la deuxième moitié du XVIe siècle par la nouvelle rhétorique ramiste.Guillaume Tardif's Rhetoricae artis ac oratoriae facultatis compendium is the second complete rhetoric to be published in Latin by a French author. Reworked in three subsequent editions, the treatise shows a keen awareness of the rhetorical tradition and a strong desire to adapt it to contemporary needs. Tardif's most original innovation lies in his classification of rhetorical figures. By dividing the figures according to their suitability to the different parts of the speech, Tardif attempts to see rhetoric as a whole, with style as a function of content. Ingenious but not always convincing, the attempt was made again by Pierre Fabri in his Grand et Vray Art depleine rhétorique (1521). Tardif's influence wanned when Fabri's work was superseded by Ramist rhetoric in the second half of the sixteenth century
Random subtrees of complete graphs
We study the asymptotic behavior of four statistics associated with subtrees
of complete graphs: the uniform probability that a random subtree is a
spanning tree of , the weighted probability (where the probability a
subtree is chosen is proportional to the number of edges in the subtree) that a
random subtree spans and the two expectations associated with these two
probabilities. We find and both approach ,
while both expectations approach the size of a spanning tree, i.e., a random
subtree of has approximately edges
Atomistic simulation of SrTiO3(001) surface relaxation
The (001) surface relaxation of the cubic perovskite SrTiO3 crystal has been studied using the shell model. The positions of atoms in several surface layers embedded in the electrostatic field of the remainder of the crystal are calculated. We show that Ti4+, Sr2+ and O2- ions in six near-surface layers are displaced differently from their crystalline sites which leads to the creation of so-called surface rumpling, a dipole moment, and an electric field in the near-surface region. Calculated atomic displacements are compared with LEED experimental data
Gas−Surface Chemical Reactions at High Collision Energies?
Most gas−surface chemical reactions occur via reaction of adsorbed species to form a thermal-energy (kT) product; however, some instances exist where an energetic projectile directly reacts with an adsorbate in a single-collision event to form a hyperthermal product (with a kinetic energy of a few eV). Here we show for the first time that 30−300 eV F^+ bombardment of fluorinated Ag and Si surfaces produces “ultrafast” F_2^− products with exit energies of up to 90 eV via a multistep direct-reaction mechanism. Experiments conclusively show that the projectile F atom ends up in the fast molecular product despite the fact that the impact energy is far greater than typical bond energies
Free Trade and Investment in the Fisheries Sector of the Asia-Pacific Region: An Economic Analysis of Tariffs
This paper was commissioned by the APEC Working Group on Fisheries to examine the economic impact of eliminating tariffs on fish and fish products in APEC economies. Chapter II provides a qualitative assessment of the impacts of liberalization of fisheries trade drawing on the available data and economic theory. Chapter III presents specific quantitative estimates of the impact on trade flows of fish and fish products using an econometrically estimated model of fisheries trade liberalization. Chapter IV summarizes the study’s overall conclusions. These are that the economic impact of the removal of tariffs on fish and fish products in the APEC region would be significant, but modest. It is estimated that, in value terms, the long- run increase in imports in the region, arising from the elimination of tariffs, would be less than 5 per cent of the 1995 level in value. The corresponding increase in exports would be equal to slightly less than 3 per cent of the 1995 level.international trade in fish and fish products, APEC region, impact of tariffs
A rank based social norms model of how people judge their levels of drunkenness whilst intoxicated
Background:
A rank based social norms model predicts that drinkers’ judgements about their drinking will be based on the rank of their breath alcohol level amongst that of others in the immediate environment, rather than their actual breath alcohol level, with lower relative rank associated with greater feelings of safety. This study tested this hypothesis and examined how people judge their levels of drunkenness and the health consequences of their drinking whilst they are intoxicated in social drinking environments.
Methods:
Breath alcohol testing of 1,862 people (mean age = 26.96 years; 61.86 % male) in drinking environments. A subset (N = 400) also answered four questions asking about their perceptions of their drunkenness and the health consequences of their drinking (plus background measures).
Results:
Perceptions of drunkenness and the health consequences of drinking were regressed on: (a) breath alcohol level, (b) the rank of the breath alcohol level amongst that of others in the same environment, and (c) covariates. Only rank of breath alcohol level predicted perceptions: How drunk they felt (b 3.78, 95 % CI 1.69 5.87), how extreme they regarded their drinking that night (b 3.7, 95 % CI 1.3 6.20), how at risk their long-term health was due to their current level of drinking (b 4.1, 95 % CI 0.2 8.0) and how likely they felt they would experience liver cirrhosis (b 4.8. 95 % CI 0.7 8.8). People were more influenced by more sober others than by more drunk others.
Conclusion:
Whilst intoxicated and in drinking environments, people base judgements regarding their drinking on how their level of intoxication ranks relative to that of others of the same gender around them, not on their actual levels of intoxication. Thus, when in the company of others who are intoxicated, drinkers were found to be more likely to underestimate their own level of drinking, drunkenness and associated risks. The implications of these results, for example that increasing the numbers of sober people in night time environments could improve subjective assessments of drunkenness, are discussed
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