How New York City Reduced Mass Incarceration: A Model for Change?

In this report, leading criminologists examine the connection between New York City's shift in policing strategies and the dramatic decrease in the City's incarcerated and correctional population

A Multiscale Investigation of Habitat Use and Within-river Distribution of Sympatric Sand Darter Species

The western sand darter Ammocrypta clara, and eastern sand darter Ammocrypta pellucida are sand-dwelling fishes of conservation concern. Past research has emphasized the importance of studying individual populations of conservation concern, while recent research has revealed the importance of incorporating landscape scale processes that structure habitat mosaics and local populations. We examined habitat use and distributions of western and eastern sand darters in the lower Elk River of West Virginia. At the sandbar habitat use scale, western sand darters were detected in sandbars with greater area, higher proportions of coarse grain sand and faster bottom current velocity, while the eastern sand darter used a wider range of sandbar habitats. The landscape scale analysis revealed that contributing drainage area was an important predictor for both species, while sinuosity, which presumably represents valley type also contributed to the western sand darter’s habitat suitability. Sandbar quality (area, grain size, and velocity) and fluvial geomorphic variables (drainage area and valley type) are likely key driving factors structuring sand darter distributions in the Elk River. This multiscale study of within-river species distribution and habitat use is unique, given that only a few sympatric populations are known of western and eastern sand darters

Validating Spray Coverage Rate Using Liquid Mass on a Spray Card

Validation of agricultural sprayers is important for quantifying as-applied coverage rates under field conditions. The complexity of modern sprayer control systems presents a challenge for precise field validation due to the use of nozzle control technologies, such as pulse width modulation, to meter chemical flow rates at individual nozzles. Non-uniform flow over time may result in local variations at high spatial resolutions that are ignored when estimating as-applied coverage rates across a field. The purpose of this study was to test several methods for estimating the mass of water applied to a water-sensitive paper spray card target using steady-state and instantaneous measurement techniques. The steady-state method consisted of a spray patternator table used to quantify the mass flow rate distribution across the nozzle width at varying nozzle pressures. The mass flow rate was then projected onto a two-dimensional area traveling across the spray width to calculate the mass of water that was deposited in the area. Two instantaneous sampling methods were used. The first method directly measured the mass of the spray card and water for 5 min after exposure to model the evaporation rate and solve for the initial mass at the time of exposure. The second method indirectly used the percent coverage of the exposed spray card by droplets. Results showed that the error between the calculated mass of water from the mass flow rate and the estimated initial mass of water from the evaporation rate varied between 2% and 8%. The relationships between the calculated and estimated initial mass of water methods and the spray card percent coverage were highly linear (R2 \u3e 0.98). Both instantaneous methods produced results with higher variability between replications than the steady-state method, but the number of replications resulted in acceptably small differences between average mass measurements. These results show the potential for using evaporation rates for laboratory validation and percent coverage for laboratory or field validation of as-applied coverage rates

Which environmental variables should I use in my biodiversity model?

Appropriate selection of environmental variables is critical to the performance of biodiversity models, but has received less attention than the choice of modelling method. Online aggregators of biological and environmental data, such as the Global Biodiversity Information Facility and the Atlas of Living Australia, necessitate a rational approach to variable selection. We outline a set of general principles for systematically identifying, compiling, evaluating and selecting environmental variables for a biodiversity model. Our approach aims to maximise the information obtained from the analysis of biological records linked to a potentially large suite of spatial environmental variables. We demonstrate the utility of this structured framework through case studies with Australian vascular plants: regional modelling of a species distribution, continent-wide modelling of species compositional turnover and environmental classification. The approach is informed by three components of a biodiversity model: (1) an ecological framework or conceptual model, (2) a data model concerning availability, resolution and variable selection and (3) a method for analysing data. We expand the data model in structuring the problem of choosing environmental variables. The case studies demonstrate a structured approach for the: (1) cost-effective compilation of variables in the context of an explicit ecological framework for the study, attribute accuracy and resolution; (2) evaluation of non-linear relationships between variables using knowledge of their derivation, scatter plots and dissimilarity matrices; (3) selection and grouping of variables based on hypotheses of relative ecological importance and perceived predictor effectiveness; (4) systematic testing of variables as predictors through the process of model building and refinement and (5) model critique, inference and synthesis using direct gradient analysis to evaluate the shape of response curves in the context of ecological theory by presenting predictions in both geographic and environmental space

The Experiences of Lesbian, Gay, Bisexual, Transgender and Queer Students in Social Work Programs. A Study Report from the CSWE Council on Sexual Orientation and Gender Identity and Expression

This online North American study of lesbian, gay, bisexual, transgender, and queer (LGBTQ) social work students (n=1,018) in bachelor of social work (BSW; 24%) or master’s of social work (MSW; 76%) programs explored educational experiences in 126 programs in 44 U. S. states and 7 Canadian provinces. Forty-four percent of students reported limited inclusion of LGBTQ content in classes, yet 64% indicated some degree of support for their LGBTQ identities in their programs. One-third reported homophobic experiences in programs, yet many (63%) were aware of “out” LGBTQ faculty. Overall, students reported fairly low levels of self-assessed practice readiness with specific subpopulations (i.e., gay, lesbian, bisexual, transgender), with participants reporting the highest (somewhat prepared) self-assessed readiness with gay populations and the lowest (not well-prepared) self-assessed readiness with transgender populations. Participants suggested lower readiness for their non-LGBTQ colleagues. Implications for social work education are discussed

Enhancing the Infrared Photoresponse of Silicon by Controlling the Fermi Level Location within an Impurity Band

Strong absorption of sub-band gap radiation by an impurity band has recently been demonstrated in silicon supersaturated with chalcogen impurities. However, despite the enhanced absorption in this material, the transformation of infrared radiation into an electrical signal via extrinsic photoconductivity—the critical performance requirement for many optoelectronic applications—has only been reported at low temperature because thermal impurity ionization overwhelms photoionization at room temperature. Here, dopant compensation is used to manipulate the optical and electronic properties and thereby improve the room-temperature infrared photoresponse. Silicon co-doped with boron and sulfur is fabricated using ion implantation and nanosecond pulsed laser melting to achieve supersaturated sulfur concentrations and a matched boron distribution. The location of the Fermi level within the sulfur-induced impurity band is controlled by tuning the acceptor-to-donor ratio, and through this dopant compensation, three orders of magnitude improvement in infrared detection at 1550 nm is demonstrated.Engineering and Applied Science

Thermal acoustic excitations with atomic-scale wavelengths in amorphous silicon

The vibrational properties of glasses remain a topic of intense interest due to several unresolved puzzles, including the origin of the Boson peak and the mechanisms of thermal transport. Inelastic scattering measurements have revealed that amorphous solids support collective acoustic excitations with low THz frequencies despite the atomic disorder, but these frequencies are well below most of the thermal vibrational spectrum. Here, we report the observation of acoustic excitations with frequencies up to 10 THz in amorphous silicon. The excitations have atomic-scale wavelengths as short as 6 Å and exist well into the thermal vibrational frequencies. Simulations indicate that these high-frequency waves are supported due to the high group velocity and monatomic composition of a-Si, suggesting that other glasses with these characteristics may also exhibit such excitations. Our findings demonstrate that a substantial portion of thermal vibrational modes in amorphous materials can still be described as a phonon gas despite the lack of atomic order

Modeling deltaic lobe‐building cycles and channel avulsions for the Yellow River delta, China

River deltas grow by repeating cycles of lobe development punctuated by channel avulsions, so that over time, lobes amalgamate to produce a composite landform. Existing models have shown that backwater hydrodynamics are important in avulsion dynamics, but the effect of lobe progradation on avulsion frequency and location has yet to be explored. Herein, a quasi‐2‐D numerical model incorporating channel avulsion and lobe development cycles is developed. The model is validated by the well‐constrained case of a prograding lobe on the Yellow River delta, China. It is determined that with lobe progradation, avulsion frequency decreases, and avulsion length increases, relative to conditions where a delta lobe does not prograde. Lobe progradation lowers the channel bed gradient, which results in channel aggradation over the delta topset that is focused farther upstream, shifting the avulsion location upstream. Furthermore, the frequency and location of channel avulsions are sensitive to the threshold in channel bed superelevation that triggers an avulsion. For example, avulsions occur less frequently with a larger superelevation threshold, resulting in greater lobe progradation and avulsions that occur farther upstream. When the delta lobe length prior to avulsion is a moderate fraction of the backwater length (0.3–0.5L_b), the interplay between variable water discharge and lobe progradation together set the avulsion location, and a model capturing both processes is necessary to predict avulsion timing and location. While this study is validated by data from the Yellow River delta, the numerical framework is rooted in physical relationships and can therefore be extended to other deltaic systems

Magic state distillation in all prime dimensions using quantum Reed-Muller codes

We propose families of protocols for magic state distillation -- important components of fault tolerance schemes --- for systems of odd prime dimension. Our protocols utilize quantum Reed-Muller codes with transversal non-Clifford gates. We find that, in higher dimensions, small and effective codes can be used that have no direct analogue in qubit (two-dimensional) systems. We present several concrete protocols, including schemes for three-dimensional (qutrit) and five-dimensional (ququint) systems. The five-dimensional protocol is, by many measures, the best magic state distillation scheme yet discovered. It excels both in terms of error threshold with respect to depolarising noise (36.3%) and the efficiency measure know as "yield", where, for a large region of parameters, it outperforms its qubit counterpart by many orders of magnitude.Comment: Updated from V1 to include results on the remarkable d=5 cas