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We review the theory and applications of complex stochastic quantization to the quantum many-body problem. Along the way, we present a brief overview of a number of ideas that either ameliorate or in some cases altogether solve the sign problem, including the classic reweighting method, alternative Hubbard-Stratonovich transformations, dual variables (for bosons and fermions), Majorana fermions, density-of-states methods, imaginary asymmetry approaches, and Lefschetz thimbles. We discuss some aspects of the mathematical underpinnings of conventional stochastic quantization, provide a few pedagogical examples, and summarize open challenges and practical solutions for the complex case. Finally, we review the recent applications of complex Langevin to quantum field theory in relativistic and nonrelativistic quantum matter, with an emphasis on the nonrelativistic case., Comment: 68 pages, 19 figures, review article, version submitted to Physics Reports

In 2011, more than 1 million Americans aged 13 and over were living with HIV infection, and one in seven did not know their infection status. Routine, voluntary HIV testing is a recognized way to reduce HIV transmission. Using data from the 2011-2013 National Survey of Family Growth (NSFG), this report updates nationally representative estimates and trends for HIV testing in the past year (excluding donation of blood or blood products, during which individuals are routinely tested) among the U.S. household population aged 15-44. Patterns of reported HIV testing in 2011-2013 are shown by age, race and Hispanic origin, education, and selected sexual behaviors that may be related to an elevated risk of HIV infection.

We present in detail two variants of the lattice Monte Carlo method aimed at tackling systems in external trapping potentials: a uniform-lattice approach with hard-wall boundary conditions, and a non-uniform Gauss-Hermite lattice approach. Using those two methods, we compute the ground-state energy and spatial density profile for systems of N=4 - 8 harmonically trapped fermions in one dimension. From the favorable comparison of both energies and density profiles (particularly in regions of low density), we conclude that the trapping potential is properly resolved by the hard-wall basis. Our work paves the way to higher dimensions and finite temperature analyses, as calculations with the hard-wall basis can be accelerated via fast Fourier transforms, the cost of unaccelerated methods is otherwise prohibitive due to the unfavorable scaling with system size., Comment: 13 pages, 3 figures

Objectives: This report shows trends and group differences in current marital status, with a focus on first marriages among women and men aged 15-44 years in the United States. Trends and group differences in the timing and duration of first marriages are also discussed. These data are based on the 2006-2010 National Survey of Family Growth (NSFG). National estimates of probabilities of first marriage by age and probabilities of separation and divorce for women and men's first marriages are presented by a variety of demographic characteristics. Data are compared with similar measures for 1982, 1995, and 2002. Methods: The analyses presented in this report are based on a nationally representative sample of 12,279 women and 10,403 men aged 15-44 years in the household population of the United States. The overall response rate for the 2006-2010 NSFG was 77%-78% for women and 75% for men. Results: The percentage of women who were currently cohabiting (living with a man in a sexual relationship) rose from 3.0% in 1982 to 11% in 2006- 2010; it was higher in some groups, including Hispanic groups, and the less educated. In 2006-2010, women and men married for the first time at older ages than in previous years. The median age at first marriage was 25.8 for women and 28.3 for men. Premarital cohabitation contributed to the delay in first marriage for both women and men.

This study examines high school students' confidence in their planned college major with an emphasis on students planning to study one of the Science, Technology, Engineering, and Mathematics (STEM) fields. The study draws on responses from the ACT Student Interest Inventory of the Illinois High School Class of 2003, which asks students about their educational and occupational plans. Analysis of 75,698 responses revealed important differences by gender, race/ethnicity, and type of planned major. Appended is a list of college majors. (Contains 7 tables and 5 figures.)

Fewnomial theory began with explicit bounds -- solely in terms of the number of variables and monomial terms -- on the number of real roots of systems of polynomial equations. Here we take the next logical step of investigating the corresponding existence problem: Let FEAS_R denote the problem of deciding whether a given system of multivariate polynomial equations with integer coefficients has a real root or not. We describe a phase-transition for when m is large enough to make FEAS_R be NP-hard, when restricted to inputs consisting of a single n-variate polynomial with exactly m monomial terms: polynomial-time for m<=n+2 (for any fixed n) and NP-hardness for m<=n+n^{epsilon} (for n varying and any fixed epsilon>0). Because of important connections between FEAS_R and A-discriminants, we then study some new families of A-discriminants whose signs can be decided within polynomial-time. (A-discriminants contain all known resultants as special cases, and the latter objects are central in algorithmic algebraic geometry.) Baker's Theorem from diophantine approximation arises as a key tool. Along the way, we also derive new quantitative bounds on the real zero sets of n-variate (n+2)-nomials., Comment: 25 pages, 5 figures. MAJOR revision of earlier version: (1) Frederic Bihan is a new co-author, (2) Theorem 1 is strengthened with a much sharper complexity threshold, (3) bounds on connected components from Theorem 2 are dramatically sharpened, (4) Theorem 3 strengthened considerably, (5) Corollary 1 removed, but theorem of Karpinski+Shparlinski on univariate discriminants is inserted, to clarify complexity comparisons

The article focuses on the acquisition and processing of aerial imagery for Stebbins, Alaska, using photogrammetry techniques. Topics include the creation of a digital surface model and orthoimagery, the application of this data for assessing riverine hazards and monitoring changes, and the availability of these resources as open-access files.

The article focuses on the collection and analysis of aerial imagery for Saint Michael, Alaska, using photogrammetry techniques. Topics include the development of a digital surface model and orthoimagery, the use of this data for evaluating riverine hazards and tracking changes, and the availability of these resources as open-access files.

Techniques employed to represent multiattribute information in an integrated, object display are reviewed and discussed. A study is proposed to investigate the effects of system parameters such as intervariable correlation on the choice of an optimal display format. The results of a psychophysical scaling study of five different displays are presented.

Long wire bundles twist into uniform spiral harnesses with help of simple apparatus. Wires pass through spacers and through hand-held tool with hole for each wire. Ends are attached to low speed bench motor. As motor turns, operator moves hand tool away forming smooth twists in wires between motor and tool. Technique produces harnesses that generate less radio-frequency interference than do irregularly twisted cables.