The Palm measure and the Voronoi tessellation for the Ginibre process

We prove that the Palm measure of the Ginibre process is obtained by removing a Gaussian distributed point from the process and adding the origin. We obtain also precise formulas describing the law of the typical cell of Ginibre--Voronoi tessellation. We show that near the germs of the cells a more important part of the area is captured in the Ginibre--Voronoi tessellation than in the Poisson--Voronoi tessellation. Moment areas of corresponding subdomains of the cells are explicitly evaluated.Comment: Published in at http://dx.doi.org/10.1214/09-AAP620 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org

Six Open String Disk Amplitude in Pure Spinor Superspace

The tree-level amplitude of six massless open strings is computed using the pure spinor formalism. The OPE poles among integrated and unintegrated vertices can be efficiently organized according to the cohomology of pure spinor superspace. The identification and use of these BRST structures and their interplay with the system of equations fulfilled by the generalized Euler integrals allow the full supersymmetric six-point amplitude to be written in compact form. Furthermore, the complete set of extended Bern-Carrasco-Johansson relations are derived from the monodromy properties of the disk world-sheet and explicitly verified for the supersymmetric numerator factors.Comment: 44pp, harvmac; v2: Final version to appear in NP

Residual effects of tracer in sequential double label deoxyglucose studies

The validity of sequential double label deoxyglucose (DG) determinations of local metabolic rate for glucose (IMRglc) was examined by quantifying the degree of trapping of residual first DG tracer during the second experimental period. One sciatic nerve was repetitively stimulated for 25 min, beginning either at the time of the DG injection or 25 min later. IMRglc in the ipsilateral dorsal horn of the lumbar spinal cord was found to be 105% and 56%, respectively, greater than that of the contralateral unstimulated side. Attempts to lower the body burden of radioactive DG by exchange blood transfusion failed to reduce this delayed effect. These data indicate that residual effects of the first tracer could obscure possible differences in IMRglc between two sequential experimental states.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29722/1/0000056.pd

Structural modification of fibroblast growth factor-binding heparan sulfate at a determinative stage of neural development

Heparan sulfate (HS) glycosaminoglycans are essential modulators of fibroblast growth factor (FGF) activity and appear to act by coupling particular forms of FGF to appropriate FGF receptors, During neural development, one particular HS proteoglycan is able to rapidly switch its potentiating activity from FGF-2, as neural precursor cell proliferation occurs, to FGF-1, as neuronal differentiation occurs, Using various analytical techniques, including chemical and enzymatic cleavage, low pressure chromatography, and strong anion-exchange high performance Liquid chromatography, we have analyzed the different HSs expressed during these crucial developmental stages, There are distinct alterations in patterns of 6-O-sulfation, total chain length, and the number of sulfated domains of the HS from the more mature embryonic brain, These changes correlate with a switch in the ability of the HS to potentiate the actions of FGF-1 in triggering: cell differentiation It thus appears that each HS pool is designed to function in the modulation of an intricate interaction with a specific growth factor and its cognate receptor, and suggests tightly regulated expression of specific, bioactive disaccharide sequences, The data can be used to construct a simple model of controlled variations in HS chain structure which have functional consequences at a crucial stage of neuronal maturation

On Estimating Conditional Conservatism

The concept of conditional conservatism (asymmetric earnings timeliness) has provided new insight into financial reporting and stimulated considerable research since Basu (1997). Patatoukas and Thomas (2011) report bias in firm-level cross-sectional asymmetry estimates that they attribute to scale effects. We do not agree with their advice that researchers should avoid conditional conservatism estimates and inferences from research based on such estimates. Our theoretical and empirical analyses suggest the explanation is a correlated omitted variables problem that can be addressed in a straightforward fashion, including fixed-effects regression. Correlation between the expected components of earnings and returns biases estimates of how earnings incorporate the information contained in returns. Further, the correlation varies with returns, biasing asymmetric timeliness estimates. When firm-specific effects are taken into account, estimates do not exhibit the bias, are statistically and economically significant, are consistent with priors, and behave as a predictable function of book-to-market, size, and leverage