Surgical treatment of craniofacial fibrous dysplasia in adults

pre-printCraniofacial fibrous dysplasia is a rare disorder that may require neurosurgical expertise for definitive management; however, surgical management of FD in adult patients is uncommon. Although other therapies have been shown to slow progression, the only definitive cure for adult craniofacial FD is complete resection with subsequent reconstruction. The authors review the biological, epidemiologic, clinical, genetic, and radiographic characteristics of adult FD, with an emphasis on surgical management of FD. They present a small series of three adult patients with complex FD that highlights the surgical complexity required in some adult patients with FD. Because of the complex nature of these adult polyostotic craniofacial cases, the authors used neurosurgical techniques specific to the different surgical indications, including a transsphenoidal approach for resection of sphenoidal sinus FD, a transmaxillary approach to decompress the maxillary branch of the trigeminal nerve with widening of the foramen rotundum, and complete calvarial craniectomy with cranioplasty reconstruction. These cases exemplify the diverse range of skull-base techniques required in the spectrum of surgical management of adult FD and demonstrate that novel variations on standard neurosurgical approaches to the skull base can provide successful outcomes with minimal complications in adults with complex craniofacial FD

Social Preferences and Voting: An Exploration Using a Novel Preference Revealing Mechanism

Public referenda are frequently used to determine the provision of public goods. As public programs have distributional consequences, a compelling question is what role if any social preferences have on voting behavior. This paper explores this issue using laboratory experiments wherein voting outcomes lead to a known distribution of net benefits across participants. Preferences are elicited using a novel Random Price Voting Mechanism (RPVM), which is a more parsimonious mechanism than dichotomous choice referenda, but gives consistent results. Results suggest that social preferences, in particular a social efficiency motive, lead to economically meaningful deviations from self-interested voting choices and increase the likelihood that welfare-enhancing programs are implemented.Institutional and Behavioral Economics, Research Methods/ Statistical Methods, C91, C92, D64, D72, H41,

ANOMALIES IN VOTING: AN EXPERIMENTAL ANALYSIS USING A NEW, DEMAND REVEALING (RANDOM PRICE VOTING) MECHANISM

This study investigates the influence of social preferences on voting decisions using a new Random Price Voting Mechanism (RPVM), which is best thought of as a public goods voting extension of the Becker-DeGroot-Marshack mechanism for private goods. In particular, this mechanism is used to investigate experimentally whether voting decisions are affected by the distribution of net benefits associated with a proposed public program. Recent papers have shown that, in additional to selfishness, factors such as inequality aversion, maximin preferences, and efficiency may influence individual decisions. However, the effect of social preferences on voting, the predominant funding mechanism for public goods by legislatures and public referenda, has not been thoroughly examined. We first establish the presence of anomalous behavior in dichotomous voting, and introduce the RPVM as a more efficient mechanism to examine such anomalies. We show that it is demand revealing in the presence of social preferences and empirically consistent with dichotomous choice voting. Laboratory experiments involving 440 subjects show that when net benefits are homogeneously distributed, the new RPVM is demand-revealing in both willingness-to-pay (WTP) and willingness-to-accept (WTA) settings, for both gains and losses. When the voting outcome potentially results in a heterogeneous distribution of (net) benefits, a systematic wedge appears between individuals' controlled induced values and their revealed WTP or WTA. With induced gains, the best-off subjects under-report their WTP and WTA in comparison to their induced value. Worst-off subjects express WTP and WTA that exceed their induced value. With induced losses a mirror image is evident. Best-off subjects over-report their induced value while the worst-off subjects under-report. Theoretical and econometric results presented in the paper suggest that these differences are caused by a concern for social efficiency.Institutional and Behavioral Economics,

An Introduction to the Ecology of Shrines in Spain

http://deepblue.lib.umich.edu/bitstream/2027.42/50836/1/54.pd

From Frictional to Viscous Behavior: Three Dimensional Imaging and Rheology of Gravitational Suspensions

We probe the three dimensional flow structure and rheology of gravitational (non-density matched) suspensions for a range of driving rates in a split-bottom geometry. We establish that for sufficiently slow flows, the suspension flows as if it were a dry granular medium, and confirm recent theoretical modeling on the rheology of split-bottom flows. For faster driving, the flow behavior is shown to be consistent with the rheological behavior predicted by the recently developed "inertial number approaches for suspension flows.Comment: 5 pages, 4 figures, accepted for Phys. Rev. E. (R

Investigation of dust bands from blue ice fields in the Lewis Cliff (Beardmore) area, Antarctica: A progress report

Blue ice fields in Antarctica are well known for their high areal meteorite concentrations. The exact type of accumulation model and the age of the ice is still not well known. Dust bands on blue ice fields may help to clarify some of these problems. Dust, which has been isolated from dust band samples from blue ice areas in the Lewis Cliff/Walcott Neve area (Beardmore region), Antarctica, was studied to determine petrographic characteristics and chemical compositions. One sample has an average grain size of around 0.5mm, and is rather different from the others in its abundances of trace elements. The REE pattern and some other trace element ratios of that sample suggest it is a sediment from the local Beacon Supergroup, which has been scooped up from the ground by ice movement. The other five samples which were investigated have very small grain sizes (20μm), and abundant glass shards. Major element data on the glass shards (and some feldspar crystals, which are also present in the dust band samples) allow the conclusion that they have originated from an alkaline volcano. The chemical composition of the glasses is highly variable, some showing basanitic composition, some showing trachytic or peralkaline K-trachytic composition. The silica vs. sum of alkalis plot shows that the Lewis Cliff samples are different from dust collected at the Allan Hills, but that there is a close similarity with volcanic material from The Pleiades, Northern Victoria Land. The trace element chemistry of all volcanic samples show the characteristic volcanic trace elements, like Ta, W, Sb, Th, and the REE, enriched by a considerable factor. The REE patterns exhibit a prominent negative Eu anomaly, which may be explained by mixing basanites (no Eu anomaly, but steep REE patterns) with K-trachytes and peralkaline K-trachytes (very pronounced negative Eu anomaly). The same components are obvious in major element analyses of individual glass shards, thus each dust band is a mixture of at least three different source materials (which, however, originated from the same volcano in a single eruption). The Pleiades seem to be a likely source for the volcanic debris found in the dust bands at Lewis Cliff