Optimal Co-linear Gaussian Beams for Spontaneous Parametric Down-Conversion

I investigate the properties of spontaneous parametric down-conversion (SPDC) involving co-linear Gaussian spatial modes for the pump and the photon collection optics. Approximate analytical and numerical results are obtained for the peak spectral density, photon bandwidth, pair collection probability, heralding ratio, and spectral purity, as a function of crystal length and beam focusing parameters. I address the optimization of these properties individually as well as jointly, and find focusing conditions that simultaneously bring the pair collection probability, heralding ratio, and spectral purity to near-optimal values. These properties are also found to be nearly scale invariant, that is, ultimately independent of crystal length. The results obtained here are expected to be useful for designing SPDC sources with high performance in multiple categories for the next generation of SPDC applications.Comment: 15 pages, 8 figures. Corrected normalization coefficient in eqn. 1 and a typo in the definition of wavenumber following eqn. 7. No results were affected by these correction

A Decade of Reform: Felony Disenfranchisement Policy in the United States

Findings published in "A Decade of Reform: Felony Disenfranchisement Policy" in the United States disclose that since 1997, sixteen states have implemented policy reforms that have reduced the restrictiveness of these laws, and more than 600,000 people in seven states have regained their voting rights

Next Big Thing? Methamphetamine in the United States

A new major study disproving the popular belief that there exists a growing methamphetamine "epidemic" within the United States. 41 page

Contour forward flux sampling: Sampling rare events along multiple collective variables

Many rare event transitions involve multiple collective variables (CVs) and the most appropriate combination of CVs is generally unknown a priori. We thus introduce a new method, contour forward flux sampling (cFFS), to study rare events with multiple CVs simultaneously. cFFS places nonlinear interfaces on-the-fly from the collective progress of the simulations, without any prior knowledge of the energy landscape or appropriate combination of CVs. We demonstrate cFFS on analytical potential energy surfaces and a conformational change in alanine dipeptide

Expressing Privacy Preferences in terms of Invasiveness

Dynamic context aware systems need highly flexible privacy protection mechanisms. We describe an extension to an existing RBAC-based mechanism that utilises a dynamic measure of invasiveness to determine whether contextual information should be released

A Survey of Studies on Judicial Selection

The Alaska legislature is considering a bill — Senate Joint Resolution 3 — that would put before voters a state constitutional amendment to change the composition of the Alaska Judicial Council and the way its members are selected. The Alaska Judicial Council plays a constitutionally-mandated role in the selection of Alaska’s judges and also makes recommendations to voters concerning retaining or not retaining judges as part of the judicial retention election process. This article reviews selected existing studies relevant to potential effects of this proposed change to the council composition — studies that examined judicial effectiveness, responsiveness of judges to public opinion, and public perception of judges. Also provided are flowcharts of the selection processes for members of the Alaska Judicial Council and of judges of the Alaska Court System; a detailed table of judicial selection methods in U.S. states and the District of Columbia; and a bibliography.Studies on Nominating Commissions / Measures of Voter Satisfaction / Objective Measures of Judicial Performance / Complexity of Judicial Decisions / Judicial Productivity and Independence / Politicization of Judicial Elections / Conclusion / Resources on Judicial Selection (bibliography) / References (bibliography)Ye

Uneven Justice: State Rates of Incarceration by Race and Ethnicity

Examines racial and ethnic disparities by state, and finds substantial variation in the degree of black-to-white incarceration. The report finds that African Americans are incarcerated at nearly six times the rate of whites and Latinos at nearly double the rate. Five states, located in the Northeast and Midwest, incarcerate blacks at more than ten times the rate of whites. Recommended reforms include: addressing disparities through changes in drug policy, mandatory sentencing laws, reconsideration of "race neutral" policies, and changes in resource allocation