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We study how participants respond to a stream of information regarding the performance of a hypothetical factory worker. Our design incorporates an experimental manipulation designed to vary the valence of worker performance.

We study how participants respond to a stream of information regarding the performance of a hypothetical factory worker.

The goal of this project is to better understand how citizens evaluate government performance. We study how participants respond to performance information using an experimental platform. This study experimentally manipulates the relevance of a performance benchmark.

The goal of this project is to better understand how citizens evaluate government performance. We study how participants respond to performance information using an experimental platform. This study is designed to identify the distribution of participants' preferences over a set of performance benchmarks.

We study how participants respond to a stream of information regarding the performance of a hypothetical factory worker. Our design incorporates experimental manipulations that vary the order in which periodic performance information is presented.

The timing and sequence of Paleogene proximal sediments derived from the rising Beartooth Range of Montana and Wyoming and shed eastward into the western Bighorn Basin have been interpreted differently by earlier workers. Improving our knowledge of the relationships between proximal and distal strata in the western Bighorn Basin will lead to a better understanding of basin development in the northern Laramide Province. The objective of this study is to use petrographic, stable isotopic and paleomagnetic datasets from Beartooth synorogenic deposits in order to address different hypotheses concerning the timing and sequence of sedimentation off the Beartooth uplift. The synorogenic strata on the west side of the basin closest to the Beartooth Range, also called proximal deposits, are variously mapped as upper Paleocene Fort Union Formation (Lopez, 2001), uppermost Paleocene-lower Eocene Willwood Formation (Love and Christensen, 1985) and lower Eocene Wasatch Formation (Raines and Johnson, 1995). These strata form a series of range-front sequences that consist of two or more packages of strata; contacts between these packages were determined to be unconformable in the field. Seven areas were studied for this project. All sequences show more deformed strata lower in the section and closer to the range front and subhorizontal or less deformed strata higher in the section. Lower strata consist of material eroded off the top of the uplift, and the upper strata contain more fragments from the underpinnings of the orogen. Petrographic data from sandstones in the western Bighorn Basin indicate the sediments were derived from a recycled orogenic provenance. Sandstone modal compositions exhibit unroofing sequences through progressively higher strata. Lower sediments are dominated by carbonate lithic fragments and recycled quartz, whereas upper strata contain greater proportions of first-cycle granitic and meta-volcanic grains. Petrographic comparisons among synorogenic units in the western Bighorn Basin show that the proximal sediments are mineralogically similar to distal sands in late Paleocene and early Eocene deposits. Lower strata along the eastern front are compositionally similar to sediments in the upper Fort Union Formation, whereas upper synorogenic strata along the northern front have sand compositions more akin to sediments in the Willwood or Wasatch formations. Stable oxygen and carbon isotope data were analyzed from calcium-carbonate cements, bulk rock, and carbonate-clast subsamples from intervals within the North Clarks Fork section. Carbonate clasts have the highest δ18O values, -5.79‰ to 10.43‰, whereas cements have the lowest δ18O values, from -11.76‰ to -1.18‰ (V-PDB); δ13C subsample values show similar characteristics. Overlap between the isotopic compositions of cement and carbonate clast suggests that most of the cement isotope compositions were inherited from carbonate fragments. Isotopic enrichment of cements occurred from the dissolution of carbonate source rocks followed by calcium carbonate precipitation during early diagenesis and from the reprecipitation of carbonate phases during late diagenesis. The most negative values are interpreted to be derived from high elevation, isotopicallydepleted, meteoric waters that mixed with carbonate-rich waters during fluvial transport and early diagenesis. Assuming early cements formed in equilibrium with shallow groundwater and an isotopic lapse rate of 2.9‰/km (Dutton et al., 2005), the precipitation was sourced in adjacent highlands a minimum of 1.6 ± 0.6 km above the early Eocene Bighorn Basin. This estimate of relief is consistent with other isotope-based relief estimates for the early Eocene from neighboring basins in the northern Laramide Province (Fan et al., 2011). Forty-six paleomagnetic sites were sampled from the North Clarks Fork section to determine polarity; ten alpha sites have mean directions in stratigraphic coordinates (tilt corrected) that are consistent with the expected early Eocene direction. The grand-alpha site mean direction (D/I) is 162.5/-75 (α95=10.1) and within error of the expected antipodal direction for the early Eocene Bighorn Basin (169/-63; α95=2.6), based on the reference pole of Diehl et al. (1983). Well-defined components in alpha sites are interpreted to be depositional remanent magnetizations that locked in a reverse polarity field during deposition. Reverse polarity alpha sites are matched to Clarkforkian-age fossils (56.8-55.4 Ma; Gingerich et al., 1980) and the Chron 24 reverse (C24r) magnetozone of the geomagnetic polarity time scale (Cande and Kent, 1995). Coupled Clarkforkian and C24r age constraints suggest that strata in the North Clarks Fork section are correlative to late Paleocene members of the Fort Union Formation. Upper synorogenic units younger than North Clarks Fork strata are likely early Eocene deposits and closer in age to the Willwood or Wasatch formations. This interpretation is consistent with changes in sandstone compositions observed in upper synorogenic sediments from this study. The findings presented here are consistent with tectonic models that call for onset of the Laramide orogeny in the northern U.S. Cordillera during the late Paleocene (Bird, 1998; Liu et al., 2010).

We performed a retrospective study of 23 patients with neurogenic sphincteric incompetence who had undergone implantation of an artificial urinary sphincter to determine if bladder capacity and compliance as determined by cystometrography could predict the need for enterocystoplasty. Study criteria were neurogenic sphincteric incompetence, no previous operations on the lower urinary tract, and performance of preoperative and postoperative cystometrography. Patients were 5 to 17 years old at implantation. Incontinence was caused by myelomeningocele (18 patients), sacral agenesis (3) and spinal cord tumor (2). The 8 patients for whom preoperative cystometric bladder capacity was greater than 60% of the expected capacity for age have been followed for a mean of 60 months. All 8 patients are continent and none required enterocystoplasty. Preoperative bladder compliance exceeded 2 ml./cm. water in all patients (group 1). Of the 15 patients for whom preoperative cystometric bladder capacity was less than 60% of the expected value (group 2, small bladders) 8 followed an average of 72 months had a compliance greater than 2 ml./cm. water and have done well without bladder augmentation. In contrast, 7 patients in this group (46%) required enterocystoplasty: 6 for persistent or recurrent incontinence and 1 for upper tract changes. The average interval between artificial sphincter placement and enterocystoplasty was 14 months. Patients with a small bladder that required augmentation had a preoperative bladder compliance of less than 2 ml./cm. water. We conclude that small bladder capacity, as determined by cystometrography in patients with neurogenic sphincteric incompetence but a bladder compliance of less than 2 ml./cm. water predicts the future need for bladder augmentation. In all other patients, with good medical treatment and followup, the possible adverse effects of a small capacity bladder can be prevented or corrected. With this strategy we have been able to avoid enterocystoplasty with its attending potential complications in 70% of our patients with neurogenic incontinence and favorable urodynamics regardless of preoperative cystometric bladder capacity.