Stops and Stares: Street Stops, Surveillance, and Race in the New Policing

The use of proactive tactics to disrupt criminal activities, such as Terry street stops and concentrated misdemeanor arrests, are essential to the “new policing.” This model applies complex metrics, strong management, and aggressive enforcement and surveillance to focus policing on high crime risk persons and places. The tactics endemic to the “new policing” gave rise in the 1990s to popular, legal, political and social science concerns about disparate treatment of minority groups in their everyday encounters with law enforcement. Empirical evidence showed that minorities were indeed stopped and arrested more frequently than similarly situated whites, even when controlling for local social and crime conditions. In this article, we examine racial disparities under a unique configuration of the street stop prong of the “new policing” – the inclusion of non-contact observations (or surveillances) in the field interrogation (or investigative stop) activity of Boston Police Department officers. We show that Boston Police officers focus significant portions of their field investigation activity in two areas: suspected and actual gang members, and the city’s high crime areas. Minority neighborhoods experience higher levels of field interrogation and surveillance activity net of crime and other social factors. Relative to white suspects, Black suspects are more likely to be observed, interrogated, and frisked or searched controlling for gang membership and prior arrest history. Moreover, relative to their black counterparts, white police officers conduct high numbers of field investigations and are more likely to frisk/search subjects of all races. We distinguish between preference-based and statistical discrimination by comparing stops by officer-suspect racial pairs. If officer activity is independent of officer race, we would infer that disproportionate stops of minorities reflect statistical discrimination. We show instead that officers seem more likely to investigate and frisk or search a minority suspect if officer and suspect race differ. We locate these results in the broader tensions of racial profiling that pose recurring social and constitutional concerns in the “new policing.”

An Analysis of Race and Ethnicity Patterns in Boston Police Department Field Interrogation, Observation, Frisk, and/or Search Reports

The report, authored by researchers from Columbia, Rutgers and the University of Massachusetts, analyzed 200,000+ encounters between BPD officers and civilians from 2007–2010. It is intended to provide a factual basis to assess the implementation of proactive policing in Boston and how it affects Boston's diverse neighborhoods. It found racial disparities in the Boston Police Department's stop-and-frisks that could not be explained by crime or other non-race factors. Blacks during that period were the subjects of 63.3% of police-civilian encounters, although less than a quarter of the city's population is Black.

Exchange Rates and the International Adjustments Process

macroeconomics, exchange rates

Confirming the thermal Comptonization model for black hole X-ray emission in the low-hard state

Hard X-ray spectra of black hole binaries in the low/hard state are well modeled by thermal Comptonization of soft seed photons by a corona-type region with $kT$\thinspace$\sim 50${\thinspace}keV and optical depth around 1. Previous spectral studies of 1E{\thinspace}1740.7$-$2942, including both the soft and the hard X-ray bands, were always limited by gaps in the spectra or by a combination of observations with imaging and non-imaging instruments. In this study, we have used three rare nearly-simultaneous observations of 1E{\thinspace}1740.7$-$1942 by both XMM-Newton and INTEGRAL satellites to combine spectra from four different imaging instruments with no data gaps, and we successfully applied the Comptonization scenario to explain the broadband X-ray spectra of this source in the low/hard state. For two of the three observations, our analysis also shows that, models including Compton reflection can adequately fit the data, in agreement with previous reports. We show that the observations can also be modeled by a more detailed Comptonization scheme. Furthermore, we find the presence of an iron K-edge absorption feature in one occasion, which confirms what had been previously observed by Suzaku. Our broadband analysis of this limited sample shows a rich spectral variability in 1E{\thinspace}1740.7$-$2942 at the low/hard state, and we address the possible causes of these variations. More simultaneous soft/hard X-ray observations of this system and other black-hole binaries would be very helpful in constraining the Comptonization scenario and shedding more light on the physics of these systems.Comment: 6 pages, two figures, accepted for publication in A&

Actin at cell-cell junctions is composed of two dynamic and functional populations

The ability of epithelial cells to polarize requires cell-cell adhesion mediated by cadherin receptors. During cell-cell contact, the mechanism via which a flat, spread cell shape is changed into a tall, cuboidal epithelial morphology is not known. We found that cadherin-dependent adhesion modulates actin dynamics by triggering changes in actin organization both locally at junctions and within the rest of the cell. Upon induction of cell-cell contacts, two spatial actin populations are distinguishable: junctional actin and peripheral thin bundles. With time, the relative position of these two populations changes and becomes indistinguishable to form a cortical actin ring that is characteristic of mature, fully polarized epithelial cells. Junctional actin and thin actin bundles differ in their actin dynamics and mechanism of formation, and interestingly, have distinct roles during epithelial polarization. Whereas junctional actin stabilizes clustered cadherin receptors at cell-cell contacts, contraction of peripheral actin bundle is essential for an increase in the maximum height at the lateral domain during polarization (cuboidal morphology). Thus, both junctional actin and thin bundles are necessary, and cooperate with each other to generate a polarized epithelial morphology

Comparison between Venetian and Western Carpathian Late Eocene bryozoan faunas.

From a critical examination of the previous papers about the Upper Eocene bryozoan faunas of NE Italy (Venetia region) and Western Carpathian Mountains (Slovakia and Hungary) it appears that there are 148 valid species (97 Cheilostomata and 50 Cyclostomata). The remarkable lithological and faunistocal affinities of the two sedimentary basins are compared and emphasized, especially with regard to the bryozoan associations. The paleogeography and relationships of these Tethyan areas are briefly examined

Early Identification of Violent Criminal Gang Members

Gang violence is a major problem in the United States accounting for a large fraction of homicides and other violent crime. In this paper, we study the problem of early identification of violent gang members. Our approach relies on modified centrality measures that take into account additional data of the individuals in the social network of co-arrestees which together with other arrest metadata provide a rich set of features for a classification algorithm. We show our approach obtains high precision and recall (0.89 and 0.78 respectively) in the case where the entire network is known and out-performs current approaches used by law-enforcement to the problem in the case where the network is discovered overtime by virtue of new arrests - mimicking real-world law-enforcement operations. Operational issues are also discussed as we are preparing to leverage this method in an operational environment.Comment: SIGKDD 201

Mtss1 promotes cell-cell junction assembly and stability through the small GTPase Rac1

Cell-cell junctions are an integral part of epithelia and are often disrupted in cancer cells during epithelial-to-mesenchymal transition (EMT), which is a main driver of metastatic spread. We show here that Metastasis suppressor-1 (Mtss1; Missing in Metastasis, MIM), a member of the IMD-family of proteins, inhibits cell-cell junction disassembly in wound healing or HGF-induced scatter assays by enhancing cell-cell junction strength. Mtss1 not only makes cells more resistant to cell-cell junction disassembly, but also accelerates the kinetics of adherens junction assembly. Mtss1 drives enhanced junction formation specifically by elevating Rac-GTP. Lastly, we show that Mtss1 depletion reduces recruitment of F-actin at cell-cell junctions. We thus propose that Mtss1 promotes Rac1 activation and actin recruitment driving junction maintenance. We suggest that the observed loss of Mtss1 in cancers may compromise junction stability and thus promote EMT and metastasis

Targeting conservation actions at species threat response thresholds

To improve the status of the world’s biodiversity by 2030, conservation actions must not only seek to halt or slow biodiversity loss, they must increase species’ populations. A better mechanistic understanding of biodiversity loss and of species’ sensitivities to certain intensities of threats is needed to target conservation actions effectively. Moving beyond ordinal space-for-time substitution analyses, towards monitoring concurrent changes in threats and species’ populations over time will help achieve this. We propose a framework to quantify species’ response thresholds along gradients of threat intensity, using a combination of threat-sensitive taxa, biogeographic regions, and biomes. This framework will allow efficient targeting of conservation actions, of relevance to global policy-making