The Dynamics of Disorder-Order Transition in Hard Sphere Colloidal Dispersions

The Physics of Hard Spheres Experiment (PHaSE) seeks a complete understanding of the entropically driven disorder-order transition in hard sphere colloidal dispersions. The light scattering instrument designed for flight collects Bragg and low angle light scattering in the forward direction via a CCD camera and performs conventional static and dynamic light scattering at 10-160 deg. through fiber optic cables. Here we report on the kinetics of nucleation and growth extracted from time-resolved Bragg images and measurements of the elastic modulus of crystalline phases obtained by monitoring resonant responses to sinusoidal forcing through dynamic light scattering. Preliminary analysis of the former indicates a significant difference from measurements on the ground, while the latter confirms nicely laboratory experiments with the same instrument and predictions from computer simulations

Improving Amendment

State constitutional amendment rules are often criticized for their poor design. The most common criticism is that the frequent use of direct democracy bypasses the virtues of representative decision making and effectively surrenders constitutional politics to well-financed special interests. Indeed, many initiative states need to improve the democratic quality of their amendment procedures. They need effective ways to foster constructive public deliberation, incentivize meaningful citizen participation, and provide checks on the influence of special interests. In this essay, I consider whether states might achieve some of those improvements if they changed the process for ratifying citizen-initiative amendments to require debate and approval by locally-elected governing bodies rather than a public referendum. The specific proposal that I explore is whether initiative states could improve their amendment processes by changing amendment rules to require ratification of citizen-initiatives by some majority of existing county governing bodies rather than a statewide referendum. Sending amendment ratification decisions to locally-elected bodies could have the beneficial effect of keeping constitutional decision-making close to citizens while at the same time retaining many of the virtues associated with representative decision-making. It might also help undermine special-interest capture by dividing the amendment power across numerous independently elected bodies rather than centralizing it within a state legislature or popular majority vote. Of course, a county-ratification model is not a panacea. There are many difficulties and costs associated with this approach. It might, for example, make the citizen-initiative too difficult to use, which would effectively shift all amendment power to the legislature. County representatives might also be ill-suited to decide statewide constitutional issues because of mismatched expertise and limited resources. A county-ratification model could also result in unconstitutional voter-dilution because of significant population differences between counties. These issues, among others, represent serious difficulties with the county-ratification model that cannot be overlooked. My goal in this essay is only to suggest that the county-ratification model deserves serious consideration as states struggle with how they might improve their amendment processes

Evaluation of sPGA x BSA as an Outcome Measure and Treatment Target for Clinical Practice

Clinical outcome measures are becoming more important in psoriasis treatment. Reliable and standardized measures of severity feasible for clinical practice are needed. Our objective was to investigate body surface area (BSA) and the product of BSA and static Physician Global Assessment (sPGA) (ie, BSA x sPGA) as potential proxy measures for PASI scores. Data were pooled from three multicenter, randomized, double-blind, placebo-controlled, phase 3 trials of ixekizumab in patients with moderate to severe psoriasis (UNCOVER-1, -2, -3; N = 3,866). Assessments included the Psoriasis Area and Severity Index (PASI), BSA, and BSA x sPGA. Rank correlations between BSA x sPGA and PASI were stronger than between BSA and PASI (baseline, r = 0.759 vs. r = 0.707; week 12, r = 0.959 vs. r = 0.924). Week 12 concordance rates with PASI responses were as follows: for 75% reduction in PASI: BSA, 86.2%; BSA x sPGA, 93.8%; for 90% reduction in PASI: BSA, 86.9%; BSA x sPGA, 88.2%. The 75% reduction in PASI positive and negative predictive values were higher for BSA x sPGA versus BSA; for 90% reduction in PASI, positive predictive value was lower and negative predictive value was higher for BSA x sPGA versus BSA. Receiver operating characteristic curve analyses identified the most accurate percentage changes in BSA and BSA x sPGA as 66% and 83% for a 75% reduction in PASI cutoff and 84% and 94% for a 90% reduction in PASI, respectively. These results suggest that BSA and BSA x sPGA are viable tools for use as a PASI proxy by real-world practitioners and may be appropriate measurements for use in clinical practice for treat-to-target strategies