The supersingular locus of the Shimura variety for GU(1,n-1) over a ramified prime

We analyze the geometry of the supersingular locus of the reduction modulo p of a Shimura variety associated to a unitary similitude group GU(1,n-1) over Q, in the case that p is ramified. We define a stratification of this locus and show that its incidence complex is closely related to a certain Bruhat-Tits simplicial complex. Each stratum is isomorphic to a Deligne-Lusztig variety associated to some symplectic group over F_p and some Coxeter element. The closure of each stratum is a normal projective variety with at most isolated singularities. The results are analogous to those of Vollaard/Wedhorn in the case when p is inert.Comment: A few more corrections, to appear in Math. Zeitschrif

Atomic absorption and fluorescence spectrometry at wavelengths below 200 nm

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The influence of legal language upon Supreme Court voting in civil liberties cases.

Scholars such as Jeffrey Segal and Harold Spaeth contend that U.S. Supreme Court decisions are based primarily upon the ideological beliefs of the justices. However, in this work I show that this conclusion is exaggerated. The aggregation of votes into a summary statistic (the percent liberal rating) and its use by Segal and Spaeth in a regression having only 21 cases creates misleading results. The truth is that political ideology is a fluctuating influence upon the Court. In some areas of civil liberties voting, ideology is a poor explanation of how cases are decided (e.g., core political speech). But in other areas, ideology is a much stronger explanation (e.g., search and seizure). In this work, I investigate whether the clarity of legal commands can explain why the influence of ideology fluctuates so much. My hypothesis is that value voting is inversely related to how clearly a right is designated by legal commands. That is, where statutes or constitutional language clearly designates a claim to liberty, ideology is a weak predictor of votes, but where law is vague and indeterminate in its nomenclature, value-voting rules. This dissertation has both a qualitative and quantitative component. It also relies upon literature that is multi-disciplinary. It accomplishes following: (1) constructs a criteria for rigidity in legal language; (2) selects cases for content analysis that meet the criteria; (3) assesses the relationship between values and votes within the selection using logistic regression analysis; (4) assesses the influence of textual rigidity upon votes cast by each individual justice for all selected cases using logistic regression analysis and (5) re-assess the attitudinal model\u27s goodness of fit for all civil liberties cases in a way that avoids ecological problems and micronumerous cases. The results of this work will show that the influence of political ideology upon judging in the Supreme Court has been overstated in the literature, and that command rigidity is a statistical predictor of judicial votes. In short, law matters

Measuring Youth Program Quality: A Guide to Assessment Tools

Thanks to growing interest in the subject of youth program quality, many tools are now available to help organizations and systems assess and improve quality. Given the size and diversity of the youth-serving sector, it is unrealistic to expect that any one tool or process will fit all programs or circumstances. This report compares the purpose, history, structure, methodology, content and technical properties of nine different program observation tools

Distributed Collision-Free Motion Coordination on a Sphere: A Conic Control Barrier Function Approach

This letter studies a distributed collision avoidance control problem for a group of rigid bodies on a sphere. A rigid body network, consisting of multiple rigid bodies constrained to a spherical surface and an interconnection topology, is first formulated. In this formulation, it is shown that motion coordination on a sphere is equivalent to attitude coordination on the 3-dimensional Special Orthogonal group. Then, an angle-based control barrier function that can handle a geodesic distance constraint on a spherical surface is presented. The proposed control barrier function is then extended to a relative motion case and applied to a collision avoidance problem for a rigid body network operating on a sphere. Each rigid body chooses its control input by solving a distributed optimization problem to achieve a nominal distributed motion coordination strategy while satisfying constraints for collision avoidance. The proposed collision-free motion coordination law is validated via simulation

Synthesis of a Photocleavable Bolalipid for the study of the roles of Phospholipid Transfer Proteins and Phosphatidylinositol Lipid Kinases

This thesis was dedicated to the synthesis of mono- and di-photocleavable phosphatidylcholine bolalipids that were designed to investigate the mechanism of action of the phospholipid transfer protein, Sec14, as well as the phosphatidylinositol 4-kinase, Pik1. While it was the goal of this thesis to synthesize both bola-PCs, only the mono-photocleavable bola-PC was successfully synthesized. The mono-photocleavable bola-PC lipid was designed to contain two glycerol molecules that each had a choline head group connected through a phosphodiester bond at the sn3 position. Each glycerol was acylated with palmitic acid at the sn1 position. These two glycerol moieties were then connected to one another through their respective sn2 hydroxyls via a mono-photocleavable dicarboxylic acid. The initial steps of this work were to synthesize mono- and di-photocleavable diacids to serve as a linker for the polar head groups of the bolalipids. The mono- and di-photocleavable diacids were designed to contain one and two nitrophenyl ethyl photolabile protecting groups, respectively. The synthesis of the di-photocleavable diacid was attempted first, however, these efforts were unsuccessful. Two separate synthetic routes were followed to synthesize this diacid, but neither were viable. Despite this, the synthesis of the mono-photocleavable diacid was successful and was incorporated into a bola-PC. The mono-photocleavable diacid and bola-PC were found to undergo photocleavage when irradiated with 365 nm light, in 60 seconds and 105 seconds, respectively. Photocleavage of the bola-PC was also carried out within a lipid vesicle comprised of 10% bola-PC and 90% DOPC. Spectral and experimental data have been provided for all compounds synthesized. Future efforts will involve the bola-PC synthesized in this thesis undergoing enzymatic conversion into a bola-PI, via the enzyme phospholipase D