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The concept of adminigration provides a much-needed lens in theorizing immigration enforcement, citizenship, and urban geographies. We define adminigration as the governance of immigrant community members through city-level policies and programs, whether or not these explicitly focus on immigrants. Our focus on adminigration involves three theoretical interventions: (1) bridging literature on immigrant bureaucratic incorporation and crimmigration to situate city-level administrative practices within immigration policymaking; (2) a focus on how localized definitions of membership, as enacted by cities, produce citizenship, legality, and illegality, and (3) the argument that these practices play out in space, resulting in variegated urban landscapes that are better characterized as a network than a level. We develop these points through a review of the literature on bureaucratic incorporation, crimmigration, citizenship, and the spatialization of immigration policymaking. To illustrate the utility of this framework, we conclude with a case study of adminigration in a California city that we call “Mayville.” 

Tropical cyclones impact estuaries via a variety of mechanisms including storm surge, flooding from precipitation, high winds, and strong wave action. Prior studies have documented disturbances caused by tropical cyclones, including prolonged periods of depressed salinity from high freshwater discharge and increased or decreased dissolved oxygen concentrations from increased loading of organic matter and/or nutrients. However, most studies of disturbance and recovery in estuaries have been limited to one or a few locations or storm events, limiting generalizations about tropical cyclone impacts and characteristic patterns of ecosystem response and recovery. We analyzed responses to 59 tropical cyclones across 19 estuaries in the eastern United States by applying a new method for detecting disturbance and recovery to long-term and high-frequency measurements of salinity and dissolved oxygen from NOAA’s National Estuarine Research Reserve System. We quantified disturbance occurrence, timing, recovery time, and severity. Salinity disturbances generally started earlier and lasted longer than dissolved oxygen disturbances. Estuaries usually recovered within days, but some disturbances lasted weeks or months. Recovery time was positively correlated with disturbance severity for both variables. Tropical cyclone properties (especially precipitation) and location characteristics were both related to disturbance characteristics. Our findings demonstrate the power of high-frequency, long-term, and cross-system data, when combined with appropriate statistical methods, for analyzing hurricanes across many estuaries to quantify disturbances. Estuaries are resilient to hurricanes for the variables and time periods considered. However, persistent impacts can potentially damage resources provided by estuaries, eroding future resilience if hurricanes become more frequent and severe. 

Bi 2 Se 3 is a widely studied 3D topological insulator having potential applications in optics, electronics, and spintronics. When the thickness of these films decreases to less than approximately 6 nm, the top and bottom surface states couple, resulting in the opening of a small gap at the Dirac point. In the 2D limit, Bi2Se3 may exhibit quantum spin Hall states. However, growing coalesced ultrathin Bi2Se3 films with a controllable thickness and typical triangular domain morphology in the few nanometer range is challenging. Here, we explore the growth of Bi2Se3 films having thicknesses down to 4 nm on sapphire substrates using molecular beam epitaxy that were then characterized with Hall measurements, atomic force microscopy, and Raman imaging. We find that substrate pretreatment—growing and decomposing a few layers of Bi2Se3 before the actual deposition—is critical to obtaining a completely coalesced film. In addition, higher growth rates and lower substrate temperatures led to improvement in surface roughness, in contrast to what is observed for conventional epitaxy. Overall, coalesced ultrathin Bi2Se3 films with lower surface roughness enable thickness-dependent studies across the transition from a 3D-topological insulator to one with gapped surface states in the 2D regime.

 

We propose a modified spatial‐voting rule to explain why congressional candidates adopt more extreme ideological positions than their constituents' preferences. Our model accepts the standard spatial‐voting model with one critical exception: voters in the same party as a candidate tolerate extremism without imposing an electoral penalty. This, in turn, creates “leeway” for candidates to adopt extreme positions as they increasingly depend on voters from their own party. Electoral simulations demonstrate that a key election‐level implication of this model is that it explains candidate polarization without relying on institutional factors like primary elections. Finally, we show that asymmetry in perceptual bias is one possible mechanism and that real‐world patterns of ideological representation are consistent with our simulation results.

 

Microstructured neutron detectors have the benefit of enhanced neutron detection efficiency as compared to planar devices, achieved by etching⁶LiF-filled trenches on the top surface of a silicon PIN diode. This sensor geometry results in a complex electric field distribution and depletion characteristics within the diode under reverse bias. For the first time on record, the effects of a fixed oxide charge on the microstructured device depletion characteristics and mobile carrier transport is investigated. Prototype detectors were fabricated with non-conformal surface doping. Capacitance voltage and current voltage measurements were performed for these prototypes and compared with COMSOL Multiphysics simulations. A spectral response from an²⁴¹Am alpha particle source was acquired and analyzed. It was found that monoenergetic alpha particles produce three prominent peaks in the pulse height spectrum output by the device. The peaks were confirmed by simulations to correlate with dead layers and incident trajectories into the microstructure. It was also found that significant differences in pulse rise time result, corresponding with events arriving in a low-field region in the fins and a high-field region in the bulk. Geant4 was utilized for radiation transport, interaction modeling, and benchmarking the spectral data. The results of this simulation work provide confidence in the ability to attain and benchmark electrical characteristics and spectral data for semiconductor radiation detectors employing complex microstructures.