This study measured knowledge and attitudes about genital herpes
and human immunodeficiency virus/acquired immunodeficiency syndrome
(HIV/AIDS) in a sample of future teachers from the College of Education at
Oregon State University. The objectives of the study were 1) to determine if
students possess accurate knowledge about the two diseases; 2)...
Analysis of observations and sensitivity experiments with a new three-dimensional global model of stable carbon isotope cycling elucidate processes that control the distribution of delta C-13 of dissolved inorganic carbon (DIC) in the contemporary and preindustrial ocean. Biological fractionation and the sinking of isotopically light delta C-13 organic matter from...
An important constraint on mechanisms of past
carbon cycle variability is provided by the stable isotopic
composition of carbon in atmospheric carbon dioxide (δ¹³C-CO₂) trapped in polar ice cores, but obtaining very precise
measurements has proven to be a significant analytical challenge.
Here we describe a new technique to determine...
A general pattern in water mass distribution and
potential shelf–basin exchange is revealed at the Laptev Sea
continental slope based on hydrochemical and stable oxygen
isotope data from the summers 2005–2009. Despite considerable
interannual variations, a frontal system can be inferred
between shelf, continental slope and central Eurasian Basin
waters...
Marine sediments from the North Pacific document two episodes of expansion and strengthening of the subsurface oxygen minimum zone (OMZ) accompanied by seafloor hypoxia during the last deglacial transition. The mechanisms driving this hypoxia remain under debate. We present a new high-resolution alkenone palaeotemperature reconstruction from the Gulf of Alaska...
Oxygen isotope data from planktonic and benthic foraminifera, on a high-resolution age model (44 ¹⁴C dates spanning 17,400 years), document deglacial environmental change on the southeast Alaska margin (59°33.32′N, 144°9.21′W, 682 m water depth). Surface freshening (i.e., δ¹⁸O reduction of 0.8‰) began at 16,650 ± 170 cal years B.P. during...
Non-intrusive track-based physical properties measurements of sediment cores recovered during ocean drilling are often biased by imperfect recovery within sediment core liners, particularly in heterogeneous and/or partially lithified sediments. These biases result in misrepresentation in measurements of true sediment physical properties, and can complicate integration of the composite site records...
Here we present the first downcore results for a new paleoproxy, the Mn/Ca ratio of foraminiferal calcite, applied to sediment accumulated in the extreme Eastern Tropical North Pacific (ETNP) over the last 30,000 years. The Mn/Ca results are compared to oxygen isotopes and sea surface temperature calculated from Mg/Ca. We...
The primary objective of Leg 138 was to provide detailed information about the ocean's response to global climate change
during the Neogene. Two north south transects were drilled (95° and 110°W) within the region of equatorial divergence driven
upwelling (and thus high accumulation rates and resolution) and spanning the major...
Benthic foraminifer and δ¹³C data from Site 849, on the west flank of the East Pacific Rise (0°11'N, 110°3l'W; 3851 m), give relatively continuous records of deep Pacific Ocean stable isotope variations between 0 and 5 Ma. The mean sample spacing is 4 k.y. Most analyses are from Cibicides wuellerstorfi>...