Comment on "Drip Paintings and Fractal Analysis", arXiv:0710.4917v2, by K. Jones-Smith, H. Mathur and L.M. Krauss

In a recent manuscript (arXiv:0710.4917v2), Jones-Smith et al. attempt to use the well-established box-counting technique for fractal analysis to "demonstrate conclusively that fractal criteria are not useful for authentication". Here, in response to what we view to be an extremely simplistic misrepresentation of our earlier work by Jones-Smith et al., we reiterate our position regarding the potential of fractal analysis for artwork authentication. We also point out some of the flaws in the analysis presented in by Jones-Smith et al.Comment: Comment on arXiv:0710.4917v2 [cond-mat.stat-mech

Comet and close-approach asteroid mission study. volume 1- summary report final report

Comet and close-approach asteroid mission stud

Multilevel Hierarchical Decomposition of Finite Element White Noise with Application to Multilevel Markov Chain Monte Carlo

In this work we develop a new hierarchical multilevel approach to generate Gaussian random field realizations in an algorithmically scalable manner that is well-suited to incorporate into multilevel Markov chain Monte Carlo (MCMC) algorithms. This approach builds off of other partial differential equation (PDE) approaches for generating Gaussian random field realizations; in particular, a single field realization may be formed by solving a reaction-diffusion PDE with a spatial white noise source function as the righthand side. While these approaches have been explored to accelerate forward uncertainty quantification tasks, e.g. multilevel Monte Carlo, the previous constructions are not directly applicable to multilevel MCMC frameworks which build fine scale random fields in a hierarchical fashion from coarse scale random fields. Our new hierarchical multilevel method relies on a hierarchical decomposition of the white noise source function in $L^2$ which allows us to form Gaussian random field realizations across multiple levels of discretization in a way that fits into multilevel MCMC algorithmic frameworks. After presenting our main theoretical results and numerical scaling results to showcase the utility of this new hierarchical PDE method for generating Gaussian random field realizations, this method is tested on a four-level MCMC algorithm to explore its feasibility

Assessment and Social Construction: Conflict or Co-Creation?

Assessment procedures in social work emerged within the historical context of modernist empiricism. They are lodged in assumptions of objectivity, measurement accuracy, value neutrality and scientific expertise. Within the context of postmodern constructionism, the grounds for traditional assessment are thrown into question. While such critique may seem to threaten the assessment tradition, such a conclusion is unwarranted. Rather, one may locate within the assessment tradition and constructionist writings converging lines of thought. Through the collaborative extension of two assessment exemplars — the genogram and the ecomap — we suggest new and more promising potentials for assessment practices in social work

Management of vaginal wall perforation during a second trimester dilation and evacuation

Background: We report an unusual case involving vaginal perforation associated with second trimester dilation and evacuation. Review of the literature fails to identify additional reports. Case: A 22 year G3P1011 female at 16 weeks gestation referred for evaluation following incomplete dilation and evacuation was found to have vaginal perforation, and communication with the peritoneal cavity on pelvic examination. Examination under anesthesia and laparoscopy confirmed multiple vaginal perforations with intraperitoneal defects and hematomas but no viscus involvement. Cervical dilation was accomplished with osmotic dilators placed under ultrasound guidance during exam under anesthesia, with evacuation completed approximately 16 hours later without further complication. Conclusion: This is the first case of vaginal perforation at time of dilation and evacuation reported in the literature. Laparoscopy should be performed to evaluate for intraabdominal injury to bowel, bladder and/or blood vessels. Use of osmotic dilators during the second trimester could potentially decrease the risk of vaginal perforation during the dilation portion of the procedure

The impact of clinical clerkships on medical students’ attitudes toward contraception and abortion: a pilot study

Objective: Investigate the impact of clinical clerkships on medical students’ attitudes toward contraception and abortion. Methods: As part of their required curriculum, second-year medical students at the University of Iowa complete an anonymous survey that presents eight questions involving specific contraception and abortion scenarios. In this pilot study, all 159 members of the Class of 2013 who had previously completed this required anonymous survey were invited to re-take the survey at the conclusion of their fourth year. Additional questions, asking the students if they felt that clinical clerkships had changed their perspectives on contraception and abortion in general, were included. Results: Of the 159 members of the Class of 2013, 42 volunteered to participate, for a response rate of 26%. Twenty students (47.62%) felt that clinical clerkships had changed their perspectives on contraception and thirteen students (39.95%) felt that clinical clerkships had changed their perspectives on abortion. The percentage of students who felt comfortable referring a patient to a colleague for an abortion increased significantly from 71.33% to 90.48% (p=0.024). Responses to the other seven questions included in the survey did not differ significantly pre and post-clerkships. Conclusions: This pilot study, although limited by a low response rate, suggests that clinical clerkships have the ability to impact medical students’ attitudes toward contraception and abortion in general, as well as toward specific scenarios involving abortion

Probing the Sensitivity of Electron Wave Interference to Disorder-Induced Scattering in Solid-State Devices

The study of electron motion in semiconductor billiards has elucidated our understanding of quantum interference and quantum chaos. The central assumption is that ionized donors generate only minor perturbations to the electron trajectories, which are determined by scattering from billiard walls. We use magnetoconductance fluctuations as a probe of the quantum interference and show that these fluctuations change radically when the scattering landscape is modified by thermally-induced charge displacement between donor sites. Our results challenge the accepted understanding of quantum interference effects in nanostructures.Comment: 8 pages, 5 figures, Submitted to Physical Review

A potential bias in coral reconstruction of sea surface temperature

Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 31 (2004): L06308, doi:10.1029/2003GL019349.Isotopic measurements in corals are used to reconstruct past sea surface temperature. These reconstructions are based on calibration regression analyses using paired measurements of modern isotopic composition and sea surface temperature. It is shown that error in these measurements of sea surface temperature can lead to substantial bias in reconstruction. Provided the variance of the measurement error is known or can be estimated, a simple correction can eliminate this bias