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Gun and street group violence remains a serious problem in cities across the United States and the focused deterrence strategy has been a widely applied law enforcement intervention to reduce it. Although two meta-analytical studies concluded that the intervention had a significant effect on violence, questions remain about how violence changes across space and time during and after the intervention. This study applies novel geospatial analyses to assess spatiotemporal changes in gun violence before, during, and after the implementation of Philadelphia Focused Deterrence. Emerging hot spot analysis employing Space-Time cubes of ten annual time bins (2009–2018) at the Thiessen polygon level was used to detect and categorize patterns. The analyses revealed a non-significant decreasing trend across the ten-year period. Furthermore, there were ninety-three statistically significant hot spots categorized into four hot spot patterns: fourteen new hot spots; twenty-three consecutive; one persistent; and fifty-three sporadic. There was no evidence showing statistically significant hot spots for the “diminishing” pattern. Knowledge of these patterns that emerge across micro-locations can be used by law enforcement practitioners to complement data-driven problem solving and fine tune these strategies and other place-based programming. Policymakers can use findings to prioritize resources when developing complementary prevention and intervention efforts by tailoring those efforts to the different emergent patterns.

Urease is an enzyme containing a dinuclear nickel active center responsible for the hydrolysis of urea into carbon dioxide and ammonia. Interestingly, inorganic models of urease are unable to mimic its mechanism despite their similarities to the enzyme active site. The reason behind the discrepancy in urea decomposition mechanisms between inorganic models and urease is still unknown. To evaluate this factor, we synthesized two bis-nickel complexes, [Ni2L(OAc)] (1) and [Ni2L(Cl)(Et3N)2] (2), based on the Trost bis-Pro-Phenol ligand (L) and encompassing different ligand labilities with coordination geometries similar to the active site of jack bean urease. Both mimetic complexes produced ammonia from urea, (1) and (2), were ten- and four-fold slower than urease, respectively. The presence and importance of several reaction intermediates were evaluated both experimentally and theoretically, indicating the aquo intermediate as a key intermediate, coordinating urea in an outer-sphere manner. Both complexes produced isocyanate, revealing an activated water molecule acting as a base. In addition, the reaction with different substrates indicated the biomimetic complexes were able to hydrolyze isocyanate. Thus, our results indicate that the formation of an outer-sphere complex in the urease analogues might be the reason urease performs a different mechanism.

This study examines changes in gun violence at the census tract level in Philadelphia, PA before and after the onset of the COVID-19 pandemic. Piecewise generalized linear mixed effects models are used to test the relative impacts of social-structural and demographic factors, police activity, the presence of and proximity to drug markets, and physical incivilities on shooting changes between 2017 and June, 2021. Model results revealed that neighborhood structural characteristics like concentrated disadvantage and racial makeup, as well as proximity to drug markets and police activity were associated with higher shooting rates. Neighborhood drug market activity and police activity significantly predicted changes in shooting rates over time after the onset of COVID-19. This work demonstrates the importance of understanding whether there are unique factors that impact the susceptibility to exogenous shocks like the COVID-19 pandemic. The increasing risk of being in a neighborhood with an active drug market during the pandemic suggests efforts related to disrupting drug organizations, or otherwise curbing violence stemming from drug markets, may go a long way towards quelling citywide increases in gun violence.

Valid and reliable measures are needed to better understand the relationship between physical activity and crime. This paper provides a comprehensive psychometric evaluation of measures developed in the Safe and Fit Environments (SAFE) Study to assess a crime-PA conceptual framework. In addition to assessing the basic psychometric properties of each measure (e.g., variable distributions [item/scale level], internal consistency reliability), this study formally examined the measurement validity and invariance of measures across four age groups using confirmatory factor analysis. The sample (n = 2173) included 336 Adolescents (aged 12–17), 532 Young adults (aged 18–39), 838 Middle Age Adults, and 467 Older Adults (aged 66+). The psychometric evaluation of (sub)scales showed consistent factorial validity and internal consistency reliability across the majority of the measures and across the four age groups. Specifically, 14 of the 17 measures displayed statistically and practically significant factor loadings and internal consistency values in the overall sample and across the age groups. The pattern of correlations for each (sub)scale with other (sub)scales/indexes largely did not exhibit redundancy across measures. The findings expanded upon the test–retest reliability evaluation reported in Patch et al. (2019), and clarified key aspects of the construct validity of these indicators. The latter bodes well for potential utility of these indicators in future predictive models.

Focused deterrence is a gang violence reduction strategy that relies on a unique mix of strong enforcement messages from law enforcement and judicial officials coupled with the promise of additional services. At the heart of the intervention is a coordinated effort to communicate the costs and consequences of gun violence to identified gang members during face-to-face meetings and additional community messaging. In Philadelphia, focused deterrence was implemented between 2013 and 2016, and although an impact evaluation showed a significant decrease in shootings in targeted areas relative to matched comparison neighborhoods, the effect on targeted gangs was not universal, with some exhibiting no change or an increase in gun-related activity. Here, we employ data on group-level social media usage and content to examine the correlations with gun violence. We find that several factors, including the nature of social media activity by the gang (e.g., extent of activity and who is engaging), are associated with increases in the average rate of gang-attributable shootings during the evaluation period, while content-specific variables (e.g., direct threats towards rivals and law enforcement) were not associated with increases in shootings. Implications for violence reduction policy, including the implementation of focused deterrence, are discussed.

Despite a small but growing literature on gang disengagement and desistance, little is known about how social networks and changes in networks correspond to self-reported changes in street gang membership over time. The current study describes the personal or “ego” network composition of 228 street gang members in two east coast cities in the United States. The study highlights changes in personal network composition associated with changes in gang membership over two waves of survey data, describing notable differences between those who reported leaving their gang and fully disengaging from their gang associates, and those who reported leaving but still participate and hang out with their gang friends. Results show some positive changes (i.e., reductions) in criminal behavior and many changes toward an increase in prosocial relationships for those who fully disengaged from their street gang, versus limited changes in both criminal behavior and network composition over time for those who reported leaving but remained engaged with their gang. The findings suggest that gang intervention programs that increase access to or support building prosocial relationships may assist the gang disengagement process and ultimately buoy desistance from crime. The study also has implications for theorizing about gang and crime desistance, in that the role of social ties should take a more central role.

Research has found that drug markets tend to cluster in space, potentially because of the profit that can be made when customers are drawn to areas with multiple suppliers. But few studies have examined how these clusters of drug markets—which have been termed “agglomeration economies”—may be related to accidental overdose deaths, and in particular, the spatial distribution of mortality from overdose. Focusing on a large neighborhood in Philadelphia, Pennsylvania, known for its open-air drug markets, this study examines whether deaths from accidental drug overdose are clustered around street corners controlled by drug trafficking gangs. This study incorporates theoretically-informed social and physical environmental characteristics of street corner units into the models predicting overdose deaths. Given a number of environmental changes relevant to drug use locations was taking place in the focal neighborhood during the analysis period, the authors first employ a novel concentration metric—the Rare Event Concentration Coefficient—to assess clustering of overdose deaths annually between 2015 and 2019. The results of these models reveal that overdose deaths became less clustered over time and that the density was considerably lower after 2017. Hence, the predictive models in this study are focused on the two-year period between 2018 and 2019. Results from spatial econometric regression models find strong support for the association between corner drug markets and accidental overdose deaths. In addition, a number of sociostructural factors, such as concentrated disadvantage, and physical environmental factors, particularly blighted housing, are associated with a higher rate of overdose deaths. Implications from this study highlight the need for efforts that strategically coordinate law enforcement, social service provision and reductions in housing blight targeted to particular geographies.

Lipase from Pseudomonas cepacia was covalently attached to magnetite nanoparticles coated with a thin polydopamine film, and employed in the enzymatic conversion of soybean oil into biodiesel, in the presence of methanol. The proposed strategy explored the direct immobilization of the enzyme via Michael addition and aldolic condensation reactions at the catechol rings, with no need of using specific coupling agents. In addition, a larger amount of enzymes could be bound to the magnetic nanoparticles, allowing their efficient recycling with the use of an external magnet. In the biodiesel conversion, the transesterification reaction was carried out directly in soybean oil by the stepwise addition of methanol, in order to circumvent its inactivation effect on the enzyme. A better yield was obtained in relation to the free enzyme, achieving 90% yield at 37 oC. However, the catalysis became gradually less effective after the third cycle, due to its prolonged exposition to the denaturating methanol medium.

Lipase B from Candida antarctica (CAL-B) is largely employed as a biocatalyst for hydrolysis, esterification, and transesterification reactions. CAL-B is a good model enzyme to study factors affecting the enzymatic structure, activity and/or stability after an immobilization process. In this study, we analyzed the immobilization of CAL-B enzyme on different magnetic nanoparticles, synthesized by the coprecipitation method inside inverse micelles made of zwitterionic surfactants, with distinct carbon chain length: 4 (ImS4), 10 (ImS10) and 18 (ImS18) carbons. Magnetic nanoparticles ImS4 and ImS10 were shown to cross-link to CAL-B enzyme via a Michael-type addition, whereas particles with ImS18 were bond via pyridine formation after glutaraldehyde cross-coupling. Interestingly, the Michael-type cross-linking generated less stable immobilized CAL-B, revealing the influence of a cross-linking mode on the resulting biocatalyst behavior. Curiously, a direct correlation between nanoparticle agglomerate sizes and CAL-B enzyme reuse stability was observed. Moreover, free CAL-B enzyme was not able to catalyze transesterification due to the high methanol concentration; however, the immobilized CAL-B enzyme reached yields from 79.7 to 90% at the same conditions. In addition, the transesterification of lipids isolated from oleaginous yeasts achieved 89% yield, which confirmed the potential of immobilized CAL-B enzyme in microbial production of biodiesel.

Valid and reliable measures are needed to better understand the relationship between physical activity and crime. This paper provides a comprehensive psychometric evaluation of measures developed in the Safe and Fit Environments (SAFE) Study to assess a crime-PA conceptual framework. In addition to assessing the basic psychometric properties of each measure (e.g., variable distributions [item/scale level], internal consistency reliability), this study formally examined the measurement validity and invariance of measures across four age groups using confirmatory factor analysis. The sample (n = 2173) included 336 Adolescents (aged 12-17), 532 Young adults (aged 18-39), 838 Middle Age Adults, and 467 Older Adults (aged 66+). The psychometric evaluation of (sub)scales showed consistent factorial validity and internal consistency reliability across the majority of the measures and across the four age groups. Specifically, 14 of the 17 measures displayed statistically and practically significant factor loadings and internal consistency values in the overall sample and across the age groups. The pattern of correlations for each (sub)scale with other (sub)scales/indexes largely did not exhibit redundancy across measures. The findings expanded upon the test-retest reliability evaluation reported in Patch et al. (2019), and clarified key aspects of the construct validity of these indicators. The latter bodes well for potential utility of these indicators in future predictive models.

The comprehension of the reactivity of the elements is an important goal to be achieved in undergraduate courses in inorganic chemistry. Therefore, at Universidade Federal de São Carlos (UFSCar), the B.Sc. in chemistry has a laboratory course dedicated to the chemistry of the elements. However, we have noticed a decrease in students' interest in this discipline over the years. Hence, we decided to use inquiry-based methodology in a full semester of an experimental laboratory of "chemistry of the elements" in an attempt to increase their interest. As a guideline, we used the theme of water treatment to engage them in solving problems related to inorganic chemistry reactivity and noticed greater enthusiasm toward the curriculum and research methodologies. Furthermore, at the end of the course, both methodologies (traditional and inquiry-based) were evaluated by an anonymous questionnaire. By using a rating from 0 to 5 (ranging from worst to best), it was evident that the mean rate for the new methodology (4.2) was significantly higher than the rate given to the traditional methodology (2.3). The improvement in the overall performance of the report grades in comparison to the traditional methodology over the inquiry-guided one was complementary to the questionnaire, indicating that poor performance was diminished or even depleted. We believe that this methodology improved the students' level of confidence and knowledge, indicating that it could be applied to any other laboratory course.

Gun and street group violence remains a serious problem in cities across the United States and the focused deterrence strategy has been a widely applied law enforcement intervention to reduce it. Although two meta-analytical studies concluded that the intervention had a significant effect on violence, questions remain about how violence changes across space and time during and after the intervention. This study applies novel geospatial analyses to assess spatiotemporal changes in gun violence before, during, and after the implementation of Philadelphia Focused Deterrence. Emerging hot spot analysis employing Space-Time cubes of ten annual time bins (2009–2018) at the Thiessen polygon level was used to detect and categorize patterns. The analyses revealed a non-significant decreasing trend across the ten-year period. Furthermore, there were ninety-three statistically significant hot spots categorized into four hot spot patterns: fourteen new hot spots; twenty-three consecutive; one persistent; and fifty-three sporadic. There was no evidence showing statistically significant hot spots for the "diminishing" pattern. Knowledge of these patterns that emerge across micro-locations can be used by law enforcement practitioners to complement data-driven problem solving and fine tune these strategies and other place-based programming. Policymakers can use findings to prioritize resources when developing complementary prevention and intervention efforts by tailoring those efforts to the different emergent patterns. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to examine the association between adolescent and parental perceptions of neighborhood safety and adolescents' physical activity in multiple locations and to investigate the moderating effect of sex within this association. Method: This cross-sectional study was conducted with 928 adolescents aged 12 to 16 years old and 1 of their parents. Adolescents and parents reported their perceptions of neighborhood safety (traffic safety, pedestrian safety, crime safety, and stranger danger safety). Adolescents reported how often they were physically active in multiple locations (physical activity in the neighborhood, in parks, and for active transport). Mixed-effects linear regression models were used to investigate these associations while controlling for demographics and the Walkability Index. Results: Parent-perceived crime safety was positively associated with adolescents' physical activity in parks (B = 0.094, p = 0.024). Parent-perceived traffic safety was positively associated with adolescents' reported physical activity in the neighborhood (B = 0.186, p = 0.014). Adolescents' physical activity for active transport was positively associated with parent-perceived traffic safety (B = 0.179, p = 0.001), stranger danger safety (B = 0.110, p = 0.013), and crime safety (B = 0.077, p = 0.035). There were 2 interactions by sex on the relation between adolescent traffic safety perception and parent pedestrian safety perception in the neighborhood and adolescents' physical activity in parks (i.e., statistically significant only for boys). Conclusions: Parents' perceptions of traffic, stranger danger, and crime safety were all related to adolescents' active transportation. Multiple safety concerns may be motivating parents to restrict adolescent mobility by walking and bicycling.

Copper nitrite reductase mimetics were synthesized using three new tridentate ligands sharing the same N,N,N motif of coordination. The ligands were based on L -proline modifications, attaching a pyridine and a triazole to the pyrrolidine ring, and differ by a pendant group (R = phenyl, n-butyl and n-propan-1-ol). All complexes coordinate nitrite, as evidenced by cyclic voltammetry, UV-Vis, FTIR and electron paramagnetic resonance (EPR) spectroscopies. The coordination mode of nitrite was assigned by FTIR and EPR as κ2O chelate mode. Upon acidification, EPR experiments indicated a shift from chelate to monodentate κO mode, and 15N NMR experiments of a Zn2+ analogue, suggested that the related Cu(II) nitrous acid complex may be reasonably stable in solution, but in equilibrium with free HONO under non catalytic conditions. Reduction of nitrite to NO was performed both chemically and electrocatalytically, observing the highest catalytic activities for the complex with n-propan-1-ol as pendant group. These results support the hypothesis that a hydrogen bond moiety in the secondary coordination sphere may aid the protonation step. [ABSTRACT FROM AUTHOR]

Background: A common hypothesis is that crime is a major barrier to physical activity, but research does not consistently support this assumption. This article advances research on crime-related safety and physical activity by developing a multilevel conceptual framework and reliable measures applicable across age groups. Methods: Criminologists and physical activity researchers collaborated to develop a conceptual framework. Survey development involved qualitative data collection and resulted in 155 items and 26 scales. Intraclass correlation coefficients (ICCs) were computed to assess test-retest reliability in a subsample of participants (N = 176). Analyses were conducted separately by age groups. Results: Test-retest reliability for most scales (63 of 104 ICCs across 4 age groups) was "excellent" or "good" (ICC ≥ .60) and only 18 ICCs were "poor" (ICC < .40). Reliability varied by age group. Adolescents (aged 12-17 y) had ICCs above the .40 threshold for 21 of 26 scales (81%). Young adults (aged 18-39 y) and middle-aged adults (aged 40-65 y) had ICCs above .40 for 24 (92%) and 23 (88%) scales, respectively. Older adults (aged 66 y and older) had ICCs above .40 for 18 of 26 scales (69%). Conclusions: The conceptual framework and reliable measures can be used to clarify the inconclusive relationships between crime-related safety and physical activity. [ABSTRACT FROM AUTHOR]

Background: This study integrated criminological and public health perspectives to examine the influence of bullying victimization and the school environment on physical activity (PA). Methods: We used a weighted sample of 7786 US middle school students surveyed as part of the Health Behavior in School-Aged Children study to conduct a multilevel analysis of bullying victimization as a predictor of self-reported PA and number of days attending physical education (PE) classes. Hierarchical models assessed the contribution of school climate and anti-crime programs. Results: Results indicated that bullying victimization was associated with fewer days in PE and lower odds of reporting at least 60 minutes of PA more than once a week. Although one of the school crime prevention policies examined was associated with more days in PE, the school-level factors did not account for a large portion of the variance in the 2-level models for either days in PE of PA. Conclusions: The results suggest that reduced levels of PA can be added to the growing list of health issues associated with bullying victimization and provide support for the importance of bullying prevention efforts in conjunction with health promotion programs targeted to middle school students. (Contains 4 tables.)

Objective: This study examined intermediate outcomes of a faith-based prisoner reentry program by assessing how client spirituality related to client- and program-level characteristics, investigating differences between completers and terminators, and examining how religious preference, religiosity/spirituality, religious salience, and incarceration's impact on spirituality influenced program completion, satisfaction, and perceived progress. Method: The study employed independent t tests, chi-square tests, and regression models to examine the influence of predictor variables. Results: Religious preference was positively associated with progress and satisfaction. In addition, individuals reporting decreases in spirituality during prison were 34 times as likely to drop out of the program compared to those who had more positive in-prison spiritual changes. Salience, general religiosity/spirituality, and spiritual experiences did not predict outcomes. Implications of the findings are discussed. (Contains 5 tables.)