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On 1 December 2011 the West Antarctic Ice Sheet (WAIS) Divide ice-core project reached its final depth of 3405 m. The WAIS Divide ice core is not only the longest US ice core to date, but is also the highest-quality deep ice core, including ice from the brittle ice zone, that the US has ever recovered. The methods used at WAIS Divide to handle and log the drilled ice, the procedures used to safely retrograde the ice back to the US National Ice Core Laboratory (NICL) and the methods used to process and sample the ice at the NICL are described and discussed.
The mineralogy and isotopic compositions of subglacially precipitated carbonate crusts (SPCCs) provide information on conditions and processes beneath former glaciers and ice sheets. Here we describe SPCCs formed on gneissic bedrock at the bed of the Laurentide Ice Sheet (LIS) during the last glacial maximum on central Baffin Island. Geochemical data indicate that the Ca in the crusts was likely derived from the subglacial chemical weathering Ca-bearing minerals in the local bedrock. C and Sr isotopic analyses reveal that the C in the calcite was derived predominantly from older plant debris. The δ18O values of the SPCCs suggest that these crusts formed in isotopic equilibrium with basal ice LIS preserved in the Barnes Ice Cap (BIC). Columnar crystal fabric and the predominance of sparite over micrite in the SPCCs are indicative of carbonate precipitation under open-system conditions. However, the mean δ18O value of the calcite crusts is ~ 10‰ higher than those of primary LIS ice preserved in the BIC, demonstrating that SPCCs record the isotopic composition of only basal ice. Palynomorph assemblages preserved within the calcite and basal BIC ice include species last endemic to the Arctic in the early Tertiary. The source of these palynomorphs remains enigmatic.
Ferroelectric oxide films have been studied for their potential application as integrated optical materials and nonvolatile memories. Electro-optic properties of potassium niobate (KNbO3) thin films have been measured and the results correlated to the microstructures observed. The growth parameters necessary to obtain single phase perovskite lead zirconate titanate (PZT) thin films are discussed. Hysteresis and fatigue measurements of the PZT films were performed to determine their characteristics for potential memory devices.
This chapter describes a framework for understanding target compliance. The framework draws from the leadership, influence, and motivation literatures to identify target-based influence triggers and the moderating variables that lead to target compliance. The chapter discusses the proposed relationships and provides directions for future research.
The role of power and influence on individual behavior is a necessary consideration in the organizational behavior and organizational theory literatures (Barbuto 2000b; Pfeffer 1981). Looking only at an agent's behaviors in trying to enact behavioral change in targets is, in many ways, like looking only at the behaviors of a truck driver who encounters a deer in the road and has to decide how to avoid an accident. The driver may consider several options to prevent a collision: flash the high-beam headlights, sound the horn, apply the brakes, or turn out of the path of the deer. Each choice is derived entirely from the truck driver's perspective, and none of them usually work to prevent an accident. The optimum solution to avoiding an accident, however, lies in understanding the behaviors of the deer, which will freeze when bright lights shine in its eyes. When the headlights are turned off, the deer will unfreeze and react to the vibrations of the road and the sight and sound of the oncoming truck, thus fleeing from the truck and avoiding the accident.
This research compared bids that consumers placed on non genetically modified (GM), organic, and conventional versions of food products in order to determine if the organic market well serves those seeking to avoid GM foods. Auction experiments using potato chips, tortilla chips, and milk chocolate were conducted with 79 subjects. Bids were modeled as a function of consumer demographics using a heteroskedastic tobit regression model. Results with the non-GM attribute nested into the organic characteristic showed that the latter's marginal effects were insignificant. This suggested the potential to further develop non-GM products for consumers not willing to pay extra for the remaining organic attributes.
Wetland research in northern Belize provides the earliest evidence for development of agriculture in the Maya Lowlands. Pollen data confirm the introduction of maize and manioc before 3000 B.C. Dramatic deforestation, beginning ca. 2500 B.C. and intensifying in wetland environments ca. 1500-1300 B.C., marks an expansion of agriculture, which occurred in the context of a mixed foraging economy. By 1000 B.C. a rise in groundwater levels led farmers to construct drainage ditches coeval with the emergence of Maya complex society ca. 1000-400 B.C. Field manipulations often involved minor modifications of natural hummocks. Canal systems are not as extensive in northern Belize as previously reported, nor is there evidence of artificially raised planting platforms. By the Classic period, wetland fields were flooded and mostly abandoned.
Two measured and weighed assemblages of lithic debitage were subjected to human treadage, one set on a compact sandy silt (“loam”) substrate, the other on unconsolidated sand. The assemblages were excavated, plotted in three dimensions, and documented for damage. Downward migration of pieces at the loam site was minimal: fracture of small pieces was the dominant damage pattern. Most sand site pieces migrated to 3-8 cm depth; vertical distribution of pieces approximated a normal curve, and edge-damage to larger pieces was the dominant damage pattern. Vertical distribution of artifacts at the sand site approximated a pattern observed in two other trampling experiments and a number of archaeological occurrences. Factors influencing these distributions are discussed.
The author singles out the new edition of Nonne's Syphilis und Nervensystem, and a new book by Wilhelm Gennerich, Die Syphilis des Zentralnervensystems, which he regards as the most important work on neuro-syphilis published to date.
A unique account of the character reactions observed and experienced during Antarctic exploration. The writer deals with the reactions of (1) the party as a whole, and (2) of sections isolated on special duties, or by misfortune. The life shows well-defined phases. The journey south and the approach to the initial goal is a time of high resolve, anticipation, and exhilaration. Quickly there follow periods of intense labour in which physique is searched to the outmost, but these are followed by times of untrammelled relaxation; these contrasts persist throughout, and produce the fascination so characteristic of polar journeys.