We describe an upper-division experiment in thermal physics where students measure the tension
of a rubber band as a function of temperature and length, and use a Maxwell relation to find the
change in internal energy and entropy for an isothermal stretch. This allows students to experimentally check the predictions...
Cyanobacteria inhabit nearly every ecosystem on earth, play a vital role in nutrient cycling, and are
useful as model organisms for fundamental research in photosynthesis and carbon and nitrogen fixation.
In addition, they are important for several established biotechnologies for producing food additives,
nutritional and pharmaceutical compounds, and pigments, as...
Advancing our ability to use invasive plants for producing commodities is central to the agricultural industry. Our objective was
to evaluate Russian knapweed (Acroptilon repens [L.] DC.) as a winter feed supplement for ruminant livestock. In Experiment
1, we utilized three ruminally cannulated steers in a completely randomized design to...
Uptake ofHNO₃ onto cirrus ice may play an important role in tropospheric NOx cycling. Discrepancies between modeled and in situ measurements of gas‐phase HNO₃ in the troposphere suggest that redistribution and removal mechanisms by cirrus ice have been poorly constrained. Limited in situ measurements have provided somewhat differing results and...
Utilizing a phase equilibria based trace element isotope model for low pressure igneous differentiation, it is now possible to update the methods presently being used to evaluate the effect of assimilation and fractional crystallization (AFC) processes. The results of the calculations presented here indicate that bulk partition coefficients (D) for...
Over the past 60 years, housing growth has outpaced population growth
in the United States. Conservationists are concerned about the far-reaching environmental
impacts of housing development, particularly in rural areas. We use
clustering analysis to examine the pattern and distribution of housing development
since 1940 in and around the Northern...
For effective species management, understanding population structure and distribution is critical. However, quantifying population structure is not always straightforward. Within the Southern Hemisphere, the blue whale (Balaenoptera musculus) complex is extremely diverse but difficult to study. Using automated detector methods, we identified “acoustic populations” of whales producing region-specific call types....
Altar (31º 29’ S, 70º 28’ W) is a large porphyry Cu-(Au-Mo) deposit with associated
epithermal Au-(Ag-Cu) veins located in the Cordillera Principal of SW San Juan Province
(Argentina). Altar is a complex magmatic-hydrothermal system formed from several
magmatic and hydrothermal pulses during the middle-late Miocene. New LA-ICPMS U-Pb
ages...
The local predictability of the El Nin˜o–Southern Oscillation (ENSO) is examined by the analysis of the
evolution of small disturbances to an unstable 4.3-yr ENSO cycle in the Cane–Zebiak model forced by perpetual
July conditions. The 4.3-yr cycle represents the dominant near-recurrent behavior in this weakly chaotic regime,
so analysis...