38 results
Technique for the Separation of Clinoptilolite from Soils
- D. W. Ming, J. B. Dixon
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- Clays and Clay Minerals / Volume 35 / Issue 6 / December 1987
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- 02 April 2024, pp. 469-472
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Kaolinite, Opal-CT, and Clinoptilolite in Altered Tuffs Interbedded with Lignite in the Jackson Group, Texas
- A. L. Senkayi, D. W. Ming, J. B. Dixon, L. R. Hossner
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- Clays and Clay Minerals / Volume 35 / Issue 4 / August 1987
- Published online by Cambridge University Press:
- 02 April 2024, pp. 281-290
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The mineralogy of partially kaolinized strata interbedded with lignite at the San Miguel mine, Atascosa County, Texas, was investigated by X-ray powder diffraction and optical and scanning electron microscopy. The San Miguel lignite occurs in the lower Jackson Group (late Eocene) of southern Texas. Based on mineralogical and micromorphological data, some of these clay partings are probably volcanic in origin and were exposed to variable degrees of in situ kaolinization in a swamp environment. Coexistence of kaolinite, clinoptilolite, and opal-CT in several of these strata suggests that the partially kaolinized volcanic layers were subjected to a subsequent resilication process following burial. Kaolinite is the dominant mineral in the oldest and most kaolinized volcanic layer (underclay) below the lowest lignite bed (seam D). The kaolinite exhibits a well-developed vermicular morphology. The youngest volcanic layer, which occurs stratigraphically above the uppermost lignite seam, is characterized by pseudomorphs of volcanic glass shards and consists mainly of clinoptilolite. Movement of siliceous ground water from this layer to the underlying strata apparently provided silica-rich solutions from which opal-CT and large (as long as 300 μm) euhedral crystals of clinoptilolite precipitated in the fossilized plant roots, veinlets, and fractures within the underlying strata. Micromorphological relationships between the Sirich (opal-CT and clinoptilolite) and sulfide (marcasite and pyrite) minerals in the fossil roots and fractures suggest that the marcasite formed before and pyrite after the resilication process.
Acidified Oxalate and Dithionite Solubility and Color of Synthetic, Partially Oxidized Al-Magnetites and Their Thermal Oxidation Products
- D. C. Golden, D. W. Ming, L. H. Bowen, R. V. Morris, H. V. Lauer, Jr.
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- Clays and Clay Minerals / Volume 42 / Issue 1 / February 1994
- Published online by Cambridge University Press:
- 28 February 2024, pp. 53-62
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Submicron-sized (~3–60 nm) powders of Al-substituted magnetite were synthesized in the laboratory by precipitation methods by mixing appropriate molar volumes FeCl2, FeCl3 and AlCl3 solutions and precipitating with 20% NH4OH. Precipitates were dialyzed for 48 hr to remove excess salts and then freeze-dried. The nominal Al mole fractions [Als = Al/(Al + Fe)] in the initial precipitate ranged from 0.001 to 0.42. Portions of the resulting powders were heated sequentially in air at 400° and 500°C. Powders were examined using X-ray diffraction (XRD), transmission electron microscopy (TEM), and visible and near-IR reflectance spectroscopy. Solubilities were determined in ammonium oxalate (pH = 3) and dithionite-citrate-bicarbonate (DCB) solutions. As determined by XRD, the mineralogy of precipitated powder samples was predominantly magnetite. Powders having Als > 0.20 contained minor goethite and a poorly crystalline iron oxide phase (ferrihydrite?), and powders having Als > 0.25 also contained gibbsite. The color of the magnetites was black throughout the range of Al-substitution. Powders heated to 400°C were reddish brown; Munsell colors ranged from 5R 2/2 to 10R 3/4 for Als from 0.1–41.5%, respectively. By XRD, these powders were maghemite, but hematite was also detected by Mössbauer spectroscopy. XRD and Mössbauer data indicate powders heated to 500°C are hematite; their Munsell colors are not noticeably different from the corresponding 400°C samples. Mean crystallite dimensions (MCDs) of the magnetite powders increase with the Al mole fraction from ~10 nm for Als = 0.001% to a maximum value of 35 nm for Als = 0.15 and decrease slightly with further increasing Al substitution. Heating magnetite powders to 400°C did not change the MCDs significantly. Heating to 500°C resulted in hematites having MCDs larger than those for corresponding precursor magnetites for Als < 0.10. The opposite is true for hematites derived from magnetites having Als > 0.10. For hematite powders with Als > 0.05, MCD decreased with increasing Al-substitution. Solubilities of powders in oxalate solutions were independent of Al content and decreased in the order unheated samples (mostly magnetite) >400°C-heated samples (maghemite + hematite) >500°C-heated samples (hematite). All powders dissolved completely in DCB. The low crystallinity of the magnetite powders and the presence of ferrous iron are responsible for their relatively high solubility in oxalate solutions.
73 Identification of 24-Month Cognitive Trajectories Among Clinical High Risk for Psychosis (CHR-P) Using Latent Class Mixture Modeling
- Ryan M. Guest, Jean Addington, Carrie E. Bearden, Kristin S. Cadenhead, Barbara A. Cornblatt, Daniel H. Mathalon, Diana O. Perkins, Ming T. Tsuang, Scott W. Woods, Tyrone D. Cannon, Matcheri S. Keshavan, William S. Stone, Elaine F. Walker
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- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 857-858
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Objective:
Cohort studies demonstrate that people who later develop schizophrenia, on average, present with mild cognitive deficits in childhood and endure a decline in adolescence and adulthood. Yet, tremendous heterogeneity exists during the course of psychotic disorders, including the prodromal period. Individuals identified to be in this period (known as CHR-P) are at heightened risk for developing psychosis (~35%) and begin to exhibit cognitive deficits. Cognitive impairments in CHR-P (as a singular group) appear to be relatively stable or ameliorate over time. A sizeable proportion has been described to decline on measures related to processing speed or verbal learning. The purpose of this analysis is to use data-driven approaches to identify latent subgroups among CHR-P based on cognitive trajectories. This will yield a clearer understanding of the timing and presentation of both general and domain-specific deficits.
Participants and Methods:Participants included 684 young people at CHR-P (ages 12–35) from the second cohort of the North American Prodromal Longitudinal Study. Performance on the MATRICS Consensus Cognitive Battery (MCCB) and the Wechsler Abbreviated Scale of Intelligence (WASI-I) was assessed at baseline, 12-, and 24-months. Tested MCCB domains include verbal learning, speed of processing, working memory, and reasoning & problem-solving. Sex- and age-based norms were utilized. The Oral Reading subtest on the Wide Range Achievement Test (WRAT4) indexed pre-morbid IQ at baseline. Latent class mixture models were used to identify distinct trajectories of cognitive performance across two years. One- to 5-class solutions were compared to decide the best solution. This determination depended on goodness-of-fit metrics, interpretability of latent trajectories, and proportion of subgroup membership (>5%).
Results:A one-class solution was found for WASI-I Full-Scale IQ, as people at CHR-P predominantly demonstrated an average IQ that increased gradually over time. For individual domains, one-class solutions also best fit the trajectories for speed of processing, verbal learning, and working memory domains. Two distinct subgroups were identified on one of the executive functioning domains, reasoning and problem-solving (NAB Mazes). The sample divided into unimpaired performance with mild improvement over time (Class I, 74%) and persistent performance two standard deviations below average (Class II, 26%). Between these classes, no significant differences were found for biological sex, age, years of education, or likelihood of conversion to psychosis (OR = 1.68, 95% CI 0.86 to 3.14). Individuals assigned to Class II did demonstrate a lower WASI-I IQ at baseline (96.3 vs. 106.3) and a lower premorbid IQ (100.8 vs. 106.2).
Conclusions:Youth at CHR-P demonstrate relatively homogeneous trajectories across time in terms of general cognition and most individual domains. In contrast, two distinct subgroups were observed with higher cognitive skills involving planning and foresight, and they notably exist independent of conversion outcome. Overall, these findings replicate and extend results from a recently published latent class analysis that examined 12-month trajectories among CHR-P using a different cognitive battery (Allott et al., 2022). Findings inform which individuals at CHR-P may be most likely to benefit from cognitive remediation and can inform about the substrates of deficits by establishing meaningful subtypes.
Characterizing sustained social anxiety in individuals at clinical high risk for psychosis: trajectory, risk factors, and functional outcomes
- Wisteria Deng, Jean Addington, Carrie E. Bearden, Kristin S. Cadenhead, Barbara A. Cornblatt, Daniel H. Mathalon, Diana O. Perkins, Larry J. Seidman, Ming T. Tsuang, Scott W. Woods, Elaine F. Walker, Tyrone D. Cannon
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- Journal:
- Psychological Medicine / Volume 53 / Issue 8 / June 2023
- Published online by Cambridge University Press:
- 11 February 2022, pp. 3644-3651
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Background
While comorbidity of clinical high-risk for psychosis (CHR-P) status and social anxiety is well-established, it remains unclear how social anxiety and positive symptoms covary over time in this population. The present study aimed to determine whether there are more than one covariant trajectory of social anxiety and positive symptoms in the North American Prodrome Longitudinal Study cohort (NAPLS 2) and, if so, to test whether the different trajectory subgroups differ in terms of genetic and environmental risk factors for psychotic disorders and general functional outcome.
MethodsIn total, 764 CHR individuals were evaluated at baseline for social anxiety and psychosis risk symptom severity and followed up every 6 months for 2 years. Application of group-based multi-trajectory modeling discerned three subgroups based on the covariant trajectories of social anxiety and positive symptoms over 2 years.
ResultsOne of the subgroups showed sustained social anxiety over time despite moderate recovery in positive symptoms, while the other two showed recovery of social anxiety below clinically significant thresholds, along with modest to moderate recovery in positive symptom severity. The trajectory group with sustained social anxiety had poorer long-term global functional outcomes than the other trajectory groups. In addition, compared with the other two trajectory groups, membership in the group with sustained social anxiety was predicted by higher levels of polygenic risk for schizophrenia and environmental stress exposures.
ConclusionsTogether, these analyses indicate differential relevance of sustained v. remitting social anxiety symptoms in the CHR-P population, which in turn may carry implications for differential intervention strategies.
A history of high-power laser research and development in the United Kingdom
- Part of
- Colin N. Danson, Malcolm White, John R. M. Barr, Thomas Bett, Peter Blyth, David Bowley, Ceri Brenner, Robert J. Collins, Neal Croxford, A. E. Bucker Dangor, Laurence Devereux, Peter E. Dyer, Anthony Dymoke-Bradshaw, Christopher B. Edwards, Paul Ewart, Allister I. Ferguson, John M. Girkin, Denis R. Hall, David C. Hanna, Wayne Harris, David I. Hillier, Christopher J. Hooker, Simon M. Hooker, Nicholas Hopps, Janet Hull, David Hunt, Dino A. Jaroszynski, Mark Kempenaars, Helmut Kessler, Sir Peter L. Knight, Steve Knight, Adrian Knowles, Ciaran L. S. Lewis, Ken S. Lipton, Abby Littlechild, John Littlechild, Peter Maggs, Graeme P. A. Malcolm, OBE, Stuart P. D. Mangles, William Martin, Paul McKenna, Richard O. Moore, Clive Morrison, Zulfikar Najmudin, David Neely, Geoff H. C. New, Michael J. Norman, Ted Paine, Anthony W. Parker, Rory R. Penman, Geoff J. Pert, Chris Pietraszewski, Andrew Randewich, Nadeem H. Rizvi, Nigel Seddon, MBE, Zheng-Ming Sheng, David Slater, Roland A. Smith, Christopher Spindloe, Roy Taylor, Gary Thomas, John W. G. Tisch, Justin S. Wark, Colin Webb, S. Mark Wiggins, Dave Willford, Trevor Winstone
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- High Power Laser Science and Engineering / Volume 9 / 2021
- Published online by Cambridge University Press:
- 27 April 2021, e18
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The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
Stress perception following childhood adversity: Unique associations with adversity type and sex
- Allison M. LoPilato, Jean Addington, Carrie E. Bearden, Kristin S. Cadenhead, Tyrone D. Cannon, Barbara A. Cornblatt, Daniel H. Mathalon, Thomas H. McGlashan, Diana O. Perkins, Ming T. Tsuang, Scott W. Woods, Elaine F. Walker
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- Development and Psychopathology / Volume 32 / Issue 1 / February 2020
- Published online by Cambridge University Press:
- 08 March 2019, pp. 343-356
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Childhood adversity is associated with poor mental and physical health outcomes across the life span. Alterations in the hypothalamic–pituitary–adrenal axis are considered a key mechanism underlying these associations, although findings have been mixed. These inconsistencies suggest that other aspects of stress processing may underlie variations in this these associations, and that differences in adversity type, sex, and age may be relevant. The current study investigated the relationship between childhood adversity, stress perception, and morning cortisol, and examined whether differences in adversity type (generalized vs. threat and deprivation), sex, and age had distinct effects on these associations. Salivary cortisol samples, daily hassle stress ratings, and retrospective measures of childhood adversity were collected from a large sample of youth at risk for serious mental illness including psychoses (n = 605, mean age = 19.3). Results indicated that childhood adversity was associated with increased stress perception, which subsequently predicted higher morning cortisol levels; however, these associations were specific to threat exposures in females. These findings highlight the role of stress perception in stress vulnerability following childhood adversity and highlight potential sex differences in the impact of threat exposures.
Clinical and functional characteristics of youth at clinical high-risk for psychosis who do not transition to psychosis
- Jean Addington, Jacqueline Stowkowy, Lu Liu, Kristin S. Cadenhead, Tyrone D. Cannon, Barbara A. Cornblatt, Thomas H. McGlashan, Diana O. Perkins, Larry J. Seidman, Ming T. Tsuang, Elaine F. Walker, Carrie E. Bearden, Daniel H. Mathalon, Olga Santesteban-Echarri, Scott W. Woods
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- Psychological Medicine / Volume 49 / Issue 10 / July 2019
- Published online by Cambridge University Press:
- 04 September 2018, pp. 1670-1677
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Background
Much of the interest in youth at clinical high risk (CHR) of psychosis has been in understanding conversion. Recent literature has suggested that less than 25% of those who meet established criteria for being at CHR of psychosis go on to develop a psychotic illness. However, little is known about the outcome of those who do not make the transition to psychosis. The aim of this paper was to examine clinical symptoms and functioning in the second North American Prodrome Longitudinal Study (NAPLS 2) of those individuals whose by the end of 2 years in the study had not developed psychosis.
MethodsIn NAPLS-2 278 CHR participants completed 2-year follow-ups and had not made the transition to psychosis. At 2-years the sample was divided into three groups – those whose symptoms were in remission, those who were still symptomatic and those whose symptoms had become more severe.
ResultsThere was no difference between those who remitted early in the study compared with those who remitted at one or 2 years. At 2-years, those in remission had fewer symptoms and improved functioning compared with the two symptomatic groups. However, all three groups had poorer social functioning and cognition than healthy controls.
ConclusionsA detailed examination of the clinical and functional outcomes of those who did not make the transition to psychosis did not contribute to predicting who may make the transition or who may have an earlier remission of attenuated psychotic symptoms.
Potentially important periods of change in the development of social and role functioning in youth at clinical high risk for psychosis
- Eva Velthorst, Jamie Zinberg, Jean Addington, Kristin S. Cadenhead, Tyrone D. Cannon, Ricardo E. Carrión, Andrea Auther, Barbara A. Cornblatt, Thomas H. McGlashan, Daniel H. Mathalon, Diana O. Perkins, Larry J. Seidman, Ming T. Tsuang, Elaine F. Walker, Scott W. Woods, Abraham Reichenberg, Carrie E. Bearden
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- Development and Psychopathology / Volume 30 / Issue 1 / February 2018
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- 19 April 2017, pp. 39-47
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The developmental course of daily functioning prior to first psychosis-onset remains poorly understood. This study explored age-related periods of change in social and role functioning. The longitudinal study included youth (aged 12–23, mean follow-up years = 1.19) at clinical high risk (CHR) for psychosis (converters [CHR-C], n = 83; nonconverters [CHR-NC], n = 275) and a healthy control group (n = 164). Mixed-model analyses were performed to determine age-related differences in social and role functioning. We limited our analyses to functioning before psychosis conversion; thus, data of CHR-C participants gathered after psychosis onset were excluded. In controls, social and role functioning improved over time. From at least age 12, functioning in CHR was poorer than in controls, and this lag persisted over time. Between ages 15 and 18, social functioning in CHR-C stagnated and diverged from that of CHR-NC, who continued to improve (p = .001). Subsequently, CHR-C lagged behind in improvement between ages 21 and 23, further distinguishing them from CHR-NC (p < .001). A similar period of stagnation was apparent for role functioning, but to a lesser extent (p = .007). The results remained consistent when we accounted for the time to conversion. Our findings suggest that CHR-C start lagging behind CHR-NC in social and role functioning in adolescence, followed by a period of further stagnation in adulthood.
Measurements of Oxychlorine species on Mars
- B. Sutter, R. C. Quinn, P. D. Archer, D. P. Glavin, T. D. Glotch, S. P. Kounaves, M. M. Osterloo, E. B. Rampe, D. W. Ming
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- International Journal of Astrobiology / Volume 16 / Issue 3 / July 2017
- Published online by Cambridge University Press:
- 05 April 2016, pp. 203-217
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Mars landed and orbiter missions have instrumentation capable of detecting oxychlorine phases (e.g. perchlorate, chlorate) on the surface. Perchlorate (~0.6 wt%) was first detected by the Wet Chemistry Laboratory in the surface material at the Phoenix Mars Landing site. Subsequent analyses by the Thermal Evolved Gas Analyser aboard the same lander detected an oxygen release (~465°C) consistent with the thermal decomposition of perchlorate. Recent thermal analysis by the Mars Science Laboratory's Sample Analysis at Mars instrument has also indicated the presence of oxychlorine phases (up to 1.2 wt%) in Gale Crater materials. Despite being at detectable concentrations, the Chemistry and Mineralogy (CheMin) X-ray diffractometer has not detected oxychlorine phases. This suggests that Gale Crater oxychlorine may exist as poorly crystalline phases or that perchlorate/chlorate mixtures exist, so that individual oxychlorine concentrations are below CheMin detection limits (~1 wt%). Although not initially designed to detect oxychlorine phases, reinterpretation of Viking Gas Chromatography/Mass Spectrometer data also suggest that oxychlorine phases are present in the Viking surface materials. Remote near-infrared spectral analyses by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument indicate that at least some martian recurring slope lineae (RSL) have spectral signatures consistent with the presence of hydrated perchlorates or chlorates during the seasons when RSL are most extensive. Despite the thermal emission spectrometer, Thermal Emission Imaging System, Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité and CRISM detection of hundreds of anhydrous chloride (~10–25 vol%) deposits, expected associated oxychlorine phases (>5–10 vol%) have not been detected. Total Cl and oxychlorine data sets from the Phoenix Lander and the Mars Science Laboratory missions could be used to develop oxychlorine versus total Cl correlations, which may constrain oxychlorine concentrations at other locations on Mars by using total Cl determined by other missions (e.g. Viking, Pathfinder, MER and Odyssey). Development of microfluidic or ‘lab-on-a-chip’ instrumentation has the potential to be the next generation analytical capability used to identify and quantify individual oxychlorine species on future landed robotic missions to Mars.
Notes
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp 159-162
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Contents
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp v-vi
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Index
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp 197-200
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6 - Reducing Crime at High-Crime Places: Practice and Evidence
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp 113-139
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Summary
The fact that crime and disorder are concentrated at a few places is interesting and deserves an explanation. It is also interesting that places show up in other criminological theories and in other disciplines. And it is useful to understand the methods for studying places. However, a primary reason we are interested in high-crime places is that it might be possible to do something about crime by addressing these places. We are convinced that focusing on places can substantially reduce crime and disorder. Our conviction is not a matter of faith, but is based on over twenty-five years of accumulating evidence.
This chapter summarizes the research evidence examining whether focusing on crime places reduces crime. We first discuss a broad range of place-based prevention strategies examined by Eck and Guerrette (2012). This review provides strong evidence for a place-based approach to crime prevention. We then turn to a specific form of place-based crime prevention – hot spots policing (Sherman and Weisburd 1995). Again, we have a strong body of evidence supporting a place-based approach. Having reviewed hot spots policing, we turn to the importance of place managers and third parties in controlling problem places. We then examine an extension of the third-party approach to argue that a place-based approach to crime may free crime control policy from the police monopoly. Then we describe how a place-based approach to crime could be incorporated in community corrections to improve probation and parole outcomes. Finally, we review the larger body of research on the potential threat of crime displacement, and its opposite, the diffusion of crime control benefits. Consistently, the evidence described in this chapter clearly shows the substantial utility of a place-based approach for reducing crime.
SITUATIONAL CRIME PREVENTION AT PLACES
In Chapter 3 we argued for the importance of social disorganization theories for understanding crime places. This is an area where basic research suggests promise (e.g., see Weisburd et al. 2012; Weisburd et al. 2014), but where there is little evidence of effectiveness of specific practices. Such evidence is beginning to be developed, but we can say little at this juncture. In contrast, the evidence regarding opportunity reduction and crime has grown systematically over the last few decades.
2 - The Concentration of Crime at Place
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 04 April 2016, pp 16-41
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Summary
Take a moment to imagine a crime occurring – perhaps a street robbery or a bag snatch. When you do this, it is difficult not to visualize the crime occurring in a particular setting or place. So, you might imagine a dark street corner with dim street lighting or seating in the outside area of a public bar. It seems intuitively sensible to analyze and understand crime at this unit of analysis – in other words, to investigate how criminals behave and crime concentrates at small microplaces. However, engaging in such microlevel analysis has tended to be a more recent criminological undertaking, and there are still many fruitful avenues to explore in terms of advancing both our knowledge and the sophistication of the methods that we use in this research area.
In this chapter, we raise and endeavor to answer a number of questions concerning the appropriate scale of analysis of criminological enquiry. To do this, we will start by defining what we mean by place and how this differs from other geographic concepts. Next, we highlight what has become the key catalyst for the criminology of place – the tremendous concentration of crime at microgeographic units of analysis. The strong and consistent concentration of crime at addresses, street segments, and other microgeographic units across cities is key to understanding why it is important to study the criminology of place and why it has such strong policy implications. We then turn to some additional statistical benefits of studying crime at microgeographic units that have to do with what is often termed “spatial interaction effects.” Finally, we examine problems that crime and place researchers will need to consider, and recommend some future directions for research exploring crime concentration at places.
PLACE AND SPACE
Geographic concepts are sometimes used in criminological research without a clear understanding of their meaning. Place and space are two such concepts. The subtle difference between them is important to keep in mind, as they can be a guide to establishing a carefully constructed study and influence the interpretation of findings. Furthermore, as will become apparent later in this chapter, a confusion of these concepts can mislead the reader in the interpretation of an argument. For example, it is important to keep in mind that place does not necessarily mean small units of analysis, nor does space necessarily refer to large areas.
Place Matters
- Criminology for the Twenty-First Century
- David Weisburd, John E. Eck, Anthony A. Braga, Cody W. Telep, Breanne Cave, Kate Bowers, Gerben Bruinsma, Charlotte Gill, Elizabeth R. Groff, Julie Hibdon, Joshua C. Hinkle, Shane D. Johnson, Brian Lawton, Cynthia Lum, Jerry H. Ratcliffe, George Rengert, Travis Taniguchi, Sue-Ming Yang
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- 05 April 2016
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- 04 April 2016
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Over the last two decades, there has been increased interest in the distribution of crime and other antisocial behavior at lower levels of geography. The focus on micro geography and its contribution to the understanding and prevention of crime has been called the 'criminology of place'. It pushes scholars to examine small geographic areas within cities, often as small as addresses or street segments, for their contribution to crime. Here, the authors describe what is known about crime and place, providing the most up-to-date and comprehensive review available. Place Matters shows that the study of criminology of place should be a central focus of criminology in the twenty-first century. It creates a tremendous opportunity for advancing our understanding of crime, and for addressing it. The book brings together eighteen top scholars in criminology and place to provide comprehensive research expanding across different themes.
4 - The Importance of Place in Mainstream Criminology and Related Fields: Influences and Lessons to be Learned
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp 68-85
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Summary
This chapter explores the importance of place in theory and research in both mainstream criminology and other disciplines. As we noted in earlier chapters, traditional criminology has focused primarily on understanding why people commit crime. This focus on criminality has generally inhibited study of microgeographies and their role in producing crime. However, more recently there has been a trend toward integrating microgeographic places into traditional theorizing about criminality. In the first part of the chapter we discuss this trend, focusing on some recent innovations in understanding criminality that have incorporated place-based perspectives. In the second part of the chapter we focus on how other disciplines have influenced thinking in this area, focusing in particular on contributions in psychology, economics, and public health. Finally, we explore how trends in other disciplines might influence future directions of study in the criminology of place.
THE GROWING ROLE OF MICROGEOGRAPHIC PLACES IN TRADITIONAL THEORIZING OF CRIMINALITY
As we noted in Chapter 1, places, at least at a macro level, played a key part in the development of criminology in the nineteenth and early twentieth centuries. But despite the role of place in crime in empirical study in Europe and theoretical development in the Chicago School through social disorganization theory, microgeographic places were mostly ignored. This was not because early criminologists failed to recognize the role of place in crime. Crime occurs in specific environments, and this was apparent to observers of the crime problem. Nonetheless, as we noted in Chapter 1, early criminologists did not see “crime places” – small discrete areas within communities – as a relevant focus of criminological study. This was the case, in part, because crime opportunities provided by places were assumed to be so numerous as to make concentration on specific places of little utility for theory or policy. What is the point of focusing theory or research on the opportunities offered by specific places if such opportunities can be found throughout the urban context?
Moreover, criminologists did not see the utility in focusing in on situational opportunities when criminal motivation was the key to understanding crime rates. Criminologists traditionally assumed that situational factors played a relatively minor role in explaining crime as compared with the “driving force of criminal dispositions” (Clarke and Felson 1993, 4; Trasler 1993).
3 - Theories of Crime and Place
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp 42-67
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Summary
In the previous chapter, we showed that crime is concentrated at very small geographic units, substantially smaller than neighborhoods, and that these concentrations, on average, are relatively stable. This is true whether examining high- or low-crime neighborhoods. Although high-crime places do cluster, they seldom form a homogeneous block of high-crime places. Rather, interspersed within concentrations of high-crime places are many low- and modest-crime places.
Why is crime concentrated in a relatively small number of places? Standard criminology has not asked this question, largely because standard criminology focuses on criminality and implicitly assumes that the density of offenders explains crime density. Recognition that place characteristics matter is the starting point for this chapter. We look at two perspectives on crime place characteristics. We use the term “perspective” because each type of explanation is comprised of multiple theories linked by a common orientation. The first perspective arises from opportunity theories of crime. The second perspective arises from social disorganization theories of crime.
We begin by contrasting two ways of thinking about how a place becomes a crime hot spot and suggest that the process by which high-crime places evolve must involve place characteristics. In the next sections, we examine opportunity and social disorganization explanations. In the final section of the chapter, we examine possible ways researchers might link these two perspectives.
PROCESSES THAT CREATE CRIME PLACES
Before we look for explanations of why places become hot spots of crime it is important to consider two processes that might lead to such an outcome. Criminologists have generally proposed two generic models to account for the processes that lead to variation in place susceptibility to crime. One model suggests that places may start with reasonably similar risks of an initial criminal attack, but once attacked the risk of a subsequent attack on the place rises. Over time, places diverge in their crime risk, and consequently in their crime counts. This temporal contagion model is also known as a boost model (see Chapter 2) or a state-dependence model. It puts the emphasis on offenders’ willingness to return to a previously successful crime site (Johnson et al. 2007; Townsley et al. 2000). It suggests that irrespective of initial crime risk the occurrence of a crime will lead to changes in risk of crime at a place.
List of figures
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp vii-x
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7 - Crime Places in the Criminological Imagination
- David Weisburd, George Mason University, Virginia, John E. Eck, University of Cincinnati, Anthony A. Braga, John F. Kennedy School of Government, Massachusetts, Cody W. Telep, Arizona State University, Breanne Cave, George Mason University, Virginia, Kate Bowers, University College London, Gerben Bruinsma, VU University Amsterdam, Charlotte Gill, George Mason University, Virginia, Elizabeth R. Groff, Temple University, Philadelphia, Julie Hibdon, Southern Illinois University, Carbondale, Joshua C. Hinkle, Georgia State University, Shane D. Johnson, University College London, Brian Lawton, John Jay College of Criminal Justice, City University of New York, Cynthia Lum, George Mason University, Virginia, Jerry H. Ratcliffe, Temple University, Philadelphia, George Rengert, Temple University, Philadelphia, Travis Taniguchi, Sue-Ming Yang, George Mason University, Virginia
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- Place Matters
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- 05 April 2016
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- 04 April 2016, pp 140-158
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Summary
We began this book by noting that criminologists have largely ignored the involvement of microgeographic places in crime. Mainstream criminologists have focused on “who done it?” and not “where done it?” (Sherman 1995). At least for the last century the key inquiries of crime and the key prevention approaches have looked to doing something about criminal motivation (Sutherland 1947; Reiss 1981). Why people commit crime has been the main focus of criminology (Brantingham and Brantingham 1990; Weisburd 2002), and catching and processing offenders has been the main focus of crime prevention (Weisburd 2008). In contrast, the criminology of place (Sherman et al. 1989; Weisburd et al. 2012), which began to develop in the 1980s and 1990s (Brantingham and Brantingham 1981; 1984; Eck 1994; Eck and Weisburd 1995; Roncek and Bell 1981; Weisburd and Green 1995a), provides an alternative vision of how we can understand crime and the crime problem. Like the emergence of community criminology during the same period (Bursik 1988; Morenoff et al. 2001; Sampson 2008; Sampson et al. 1997) the criminology of place has offered a new set of mechanisms for crime study and a new set of methods for doing something about the crime problem.
Theory has been a driving force in criminological study, and as we note below, we think that more not less attention to theory is important for advancing the criminology of place. However, theories are about something and try to explain something. When we change the unit of analysis, we are changing the target for theory. The criminology of place proposes a new target. It focuses on places, rather than people. Its goal is to explain the criminal involvement of microgeographic units rather than trying to explain the criminal involvement of people. This does not mean we ignore the role of individuals in the crime problem. But it does mean that we begin our inquiries with the place and see the individuals as only one part of the crime equation at places.
We have illustrated in the preceding chapters the extent to which theory, method, and empirical evidence about crime places have been developing over the last three decades. In this concluding chapter, we want to draw from our review of what is known some key themes that we think our work has identified, and key questions that still need to be answered.