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Abstract Supply chain disruptions negatively impact the economy and individual organizations. However, as many companies recover from disruptions (COVID-19 being a recent example), less attention has been paid to how [...]

Municipal governments commonly confront the problem of tardy or delinquent property tax payments. We implement an experiment in property tax collection for tardy taxpayers in the City of Philadelphia for the calendar year 2015. The experiment sent one of seven reminder letters to the tardy taxpayers, testing the efficacy of a simple reminder; two alternative reminders stressing economic sanctions; and four alternative reminders emphasizing either that taxpayers receive neighborhood services or city-wide services for their tax payments, that most of their neighbors pay their taxes on time, or that as a citizen in a democracy it is a civic duty to pay taxes on time. Compliance behaviors were compared to a holdout sample that received no reminder letter. The most effective letters were those that threatened an economic sanction for continued non-compliance. These letters were particularly cost-effective in raising additional city revenues. There was no evidence that those receiving a reminder for calendar year 2015 improved their tax compliance behavior in calendar year 2016. Keywords: tax compliance, property taxation, field experiment, deterrence, public service appeal, appeal to civic duty JEL Codes: H2, H7, I. INTRODUCTION Property taxation is the primary tax for most U.S. cities. In fiscal year 2016, 47 percent of all local government revenues and over 72 percent of local taxes [...]

Zircon megacrysts are locally abundant in 1-40 cm-thick orthopyroxenite veins within peridotite host rocks in the Archaean Lewisian gneiss complex from NW Scotland. The veins formed by metasomatic interaction between the ultramafic host and Si-rich melts are derived from partial melting of the adjacent granulite-facies orthogneisses. The interaction produced abundant orthopyroxene and, within the thicker veins, phlogopite, pargasite and feldspathic bearing assemblages. Two generations of zircon are present with up to 1 cm megacrystic zircon and a later smaller equant population located around the megacryst margins. Patterns of zoning, rare earth element abundance and oxygen isotopic compositions indicate that the megacrysts crystallized from crustal melts, whereas the equant zircon represents new neocryst growth and partial replacement of the megacryst zircon within the ultramafic host. Both zircon types have U-Pb ages of ca. 2464 Ma, broadly contemporaneous with granulite-facies events in the adjacent gneisses. Zircon megacrysts locally form > 10% of the assemblage and may be associated to zones of localized nucleation or physically concentrated during movement of the siliceous melts. Their unusual size is linked to the suppression of zircon nucleation and increased Zr solubility in the Si-undersaturated melts. The metasomatism between crustal melts and peridotite may represent an analog for processes in the mantle wedge above subducting slabs. As such, the crystallization of abundant zircon in ultramafic host rocks has implications for geochemistry of melts generated in the mantle and the widely reported depletion of high field strength elements in arc magmas., Author(s): John W. Faithfull [sup.1] , Tim J. Dempster [sup.2] , John M. MacDonald [sup.2] , Monica Reilly [sup.2] Author Affiliations: (Aff1) 0000 0001 2193 314X, grid.8756.c, The Hunterian, University [...]

Gunther Abrahamson, who died in Ottawa on 8 April 2016, steered federal government programs in the North for three critical decades. He entered government service in 1959, at the time [...]

Zircon is a key mineral in geochemical and geochronological studies in a range of geological settings as it is mechanically and chemically robust. However, distortion of its crystal lattice can facilitate enhanced diffusion of key elements such as U and Pb. Electron backscatter diffraction (EBSD) analysis of ninety-nine zircons from the Lewisian Gneiss Complex (LGC) of northwest Scotland has revealed five zircons with lattice distortion. The distortion can take the form of gradual bending of the lattice or division of the crystal into subgrains. Zircon lattices are distorted because of either post-crystallisation plastic distortion or growth defects. Three of the five distorted zircons, along with many of the undistorted zircons in the population, were analysed by ion microprobe to measure U and Pb isotopes, Ti and REEs. Comparison of Th/U ratio, [sup.207]Pb/[sup.206]Pb age, REE profile and Ti concentration between zircons with and without lattice distortion suggests that the distortion is variably affecting the concentration of these trace elements and isotopes within single crystals, within samples and between localities. REE patterns vary heterogeneously, sometimes relatively depleted in heavy REEs or lacking a Eu anomaly. Ti-in-zircon thermometry records temperatures that were either low (~700°C) or high (>900°C) relative to undistorted zircons. One distorted zircon records apparent [sup.207]Pb/[sup.206]Pb isotopic ages (-3.0 to +0.3 % discordance) in the range of ~2,420-2,450 Ma but this does not correlate with any previously dated tectonothermal event in the LGC. Two other distorted zircons give discordant ages of 2,331 ± 22 and 2,266 ± 40 Ma, defining a discordia lower intercept within error of a late amphibolite-facies tectonothermal event. This illustrates that Pb may be mobilised in distorted zircons at lower metamorphic grade than in undistorted zircons. These differences in trace element abundances and isotope systematics in distorted zircons relative to undistorted zircons are generally interpreted to have been facilitated by subgrain walls. Trace elements and isotopes would have moved from undistorted lattice into these subgrain walls as their chemical potential is modified due to the presence of the dislocations which make up the subgrain wall. Subgrain walls provided pathways for chemical exchange between crystal and surroundings. Only five per cent of zircons in this population have lattice distortion suggesting it will not have a major impact on zircon geochronology studies, particularly as three of the five distorted zircons are from strongly deformed rocks not normally sampled in such studies. However, this does suggest there may be a case for EBSD analysis of zircons prior to geochemical analysis when zircons from highly deformed rocks are to be investigated. Keywords Zircon * Lattice distortion * Trace elements and isotopes * EBSD, Introduction Zircon is a common accessory mineral in a wide range of sedimentary, igneous and metamorphic rocks. It has a high volume diffusion closure temperature of typically >900°C for radiogenic [...]

III. EMPIRICAL ANALYSIS OF THE EFFECT OF LAND USE LAW ON THE BUILT ENVIRONMENT AND CRIME The core research question in this Article is whether there exists a relationship between [...]

The idea of using law to change the built environment in ways that reduce opportunities to commit crimes has a long history. Unfortunately, this idea has received relatively little attention [...]

Abstract Recent catastrophic events have disrupted supply chains around the globe, causing practitioners and academics to look more closely at recovery strategies. Recent examinations of supply chain disruptions focus primarily [...]

Despite drastic and severe fiscal cuts in services to the homeless, their need continues to remain very high. Men are a particularly vulnerable group among the homeless and continue to struggle with substance abuse, mental illness, and physical health issues. When faced with these struggles, men are often reluctant to ask for help. The results indicate that the men surveyed are not likely to seek help for their physical and psychological struggles. We examined other risk factors to homeless men including amount of alcohol and drug use, length of homelessness, gender role conflict and susceptibility to committing a violent act. Limitations to the study are presented and discussed as well. Keywords: homelessness, men, help-seeking behavior, gender role conflict, violence, Homeless men and women are often visible on the street corners and benches in most large urban cities and rural communities. Many are recognizable by their unkempt appearance, displays of [...]

Theoretically, health-related policies are driven by an assessment of population need and are based on evidence of both need and resources. In practice, however, many other factors and stakeholders exert [...]

Business improvement districts (BIDs) have been lauded and criticized for their special services provisions that putatively create community economic development environments in urban areas. Few studies have examined how specific BID functions operate within the larger context of community environments. This study describes BIDs in Los Angeles and examines whether their priorities align with underlying community conditions and economic development concerns. Relying on multiple sources of data, we find that there appears to be notable diversity in the budgets and expenditures of BIDs, some of which align with observed community conditions. BID operational priorities are associated with the environments in which they are situated. There is little evidence that BID priorities are universally focused on a single set of interests. The political economy of these organizations within their community context is critical to understanding their operations, appeal, and controversy. KEYWORDS: business improvement districts, community economic development, Los Angeles

Objectives. We investigated the effect of the use of less-lethal weapons, conductive energy devices (CEDs), and oleoresin capsicum (OC) spray on the prevalence and incidence of injuries to police officers and civilians in encounters involving the use of force. Methods. We analyzed data from 12 police departments that documented injuries to officers and civilians in 24380 cases. We examined monthly injury rates for 2 police departments before and after their adoption of CEDs. Results. Odds of injury to civilians and officers were significantly lower when police used CED weapons, after control for differences in case attributes and departmental policies restricting use of these weapons. Monthly incidence of injury in 2 police departments declined significantly, by 25% to 62%, after adoption of CED devices. Conclusions. Injuries sustained during police use-of-force events affect thousands of police officers and civilians in the United States each year. Incidence of these injuries can be reduced dramatically when law enforcement agencies responsibly employ less-lethal weapons in lieu of physical force. (Am J Public Health. 2009;99:2268-2274. doi: 10.2105/AJPH.2009.159616)

Understanding the progression of violent and nonviolent criminal activity remains a matter of theoretical debate. In the present study, the authors build on criminological theory and assess the extent to which the progression of violent and nonviolent criminal behaviors follows different trajectories. The authors rely on semiparametric mixture models to examine these comorbidities of offending in a longitudinal sample of delinquent adolescents. The results suggest that the trajectories of violent and nonviolent criminal offending follow similar paths over time and that membership in the chronic violent and nonviolent offender groups are associated with overlapping sets of risk factors. However, the results also indicate that at the individual level, membership in a particular nonviolent offending group does not share high concordance with membership in a particular violent offender group. These findings raise questions about the adequacy of general theories of crime progression and suggest the need to continue investigating behavioral theories that discriminate between different forms of offending. Keywords offending trajectories, violent offending, delinquent offenders DOI: 10.1177/0022427809341945

Allegations of racially biased policing are a contentious issue in many communities. Processes that flag potential problem officers have become a key component of risk management systems at major police departments. We present a statistical method to flag potential problem officers by blending three methodologies that are the focus of active research efforts: propensity score weighting, doubly robust estimation, and false discovery rates. Compared with other systems currently in use, the proposed method reduces the risk of flagging a substantial number of false positives by more rigorously adjusting for potential confounders and by using the false discovery rate as a measure to flag officers. We apply the methodology to data on 500,000 pedestrian stops in New York City in 2006. Of the nearly 3,000 New York City Police Department officers regularly involved in pedestrian stops, we flag 15 officers who stopped a substantially greater fraction of black and Hispanic suspects than our statistical benchmark predicts. KEY WORDS: Propensity score weighting; Racial profiling; Risk management systems.

We propose an optical design for miniature 2.5x zoom fold optics with liquid elements. First, we reduce the volumetric size of the system. Second, this newly developed design significantly reduces the number of moving groups for this 2.5x miniature zoom optics (with only two moving groups compared with the four or five groups of the traditional zoom lens system), thanks to the assistance of liquid lens elements in particular. With regard to the extended optimization of this zoom optics, relative illuminance (RI) and the modulation transfer function (MTF) are considered because the more rays passing through the edge of the image, the lower will be the MTF, at high spatial frequencies in particular. Extended optimization employs the integration of the Taguchi method and the robust multiple criterion optimization (RMCO) approach. In this approach, a Pareto optimal robust design solution is set with the aid of a certain design of the experimental set, which uses analysis of variance results to quantify the relative dominance and significance of the design factors. It is concluded that the Taguchi method and RMCO approach is successful in optimizing the RI and MTF values of the fold 2.5x zoom lens system and yields better and more balanced performance, which is very difficult for the traditional least damping square method to achieve. OCIS codes: 110.0110, 120.3620, 220.1000, 220.0220.

Men's and boys' health is a significant public health issue in Australia and, by most indicators, it is poorer than that of women. Numerous epidemiological studies have found premature deaths [...]

A study to determine if addition of gemcitabine to adjuvant fluorouracil chemoradiation increased the survival rate of patients with resected pancreatic adenocarcinoma is conducted. Results indicate an improved survival rate but were not statistically significant.

Racial differences exist in perceptions of criminal justice. Race remains a significant predictor of perceptions of unjust police practices and suggests measures for police reform.

Exposure to low [Ca.sup.2+] and/or [Mg.sup.2+] is tolerated by cardiac myocytes, astrocytes, and neurons, but restoration to normal divalent cation levels paradoxically causes [Ca.sup.2+] overload and cell death. This phenomenon has been called the '[Ca.sup.2+] paradox' of ischemia-reperfusion. The mechanism by which a decrease in extracellular [Ca.sup.2+] and [Mg.sup.2+] is 'detected' and triggers subsequent cell death is unknown. Transient periods of brain ischemia are characterized by substantial decreases in extracellular [Ca.sup.2+] and [Mg.sup.2+] that mimic the initial condition of the [Ca.sup.2+] paradox. In CA1 hippocampal neurons, lowering extracellular divalents stimulates a nonselective cation current. We show that this current resembles TRPM7 currents in several ways. Both (i) respond to transient decreases in extracellular divalents with inward currents and cell excitation, (ii) demonstrate outward rectification that depends on the presence of extracellular divalents, (iii) are inhibited by physiological concentrations of intracellular [Mg.sup.2+], (iv) are enhanced by intracellular phosphatidylinositol 4,5-bisphosphate ([PIP.sub.2]), and (v) can be inhibited by G[alpha]q-linked G protein-coupled receptors linked to phospholipase C [beta]1-induced hydrolysis of [PIP.sub.2]. Furthermore, suppression of TRPM7 expression in hippocampal neurons strongly depressed the inward currents evoked by lowering extracellular divalents. Finally, we show that activation of TRPM7 channels by lowering divalents significantly contributes to cell death. Together, the results demonstrate that TRPM7 contributes to the mechanism by which hippocampal neurons 'detect' reductions in extracellular divalents and provide a means by which TRPM7 contributes to neuronal death during transient brain ischemia. calcium paradox | divalent cation sensing | siRNA | ischemia

Two different types of Gauss lens design, which effectively eliminate primary chromatic aberration, are presented using an efficient genetic algorithm (GA). The current GA has to deal with too many targets in optical global optimization so that the performance is not much improved. Generally speaking, achromatic aberrations have a great relationship with variable glass sets for all elements. For optics whose design is roughly convergent, glass sets for optics will play a significant role in axial and lateral color aberration. Therefore better results might be derived from the optimal process of eliminating achromatic aberration, which could be carried out by finding feasible glass sets in advance. As an alternative, we propose a new optimization process by using a GA and involving theories of geometrical optics in order to select the best optical glass combination. Two Gauss-type lens designs are employed in this research. First, a telephoto lens design is sensitive to axial aberration because of its long focal length, and second, a wide-angle Gauss design is complicated by lateral color aberration at the extreme corners because Gauss design is well known not to deal well with wide-angle problems. Without numbers of higher chief rays passing the element, it is difficult to correct lateral color aberration altogether for the Gauss design. The results and conclusions show that the attempts to eliminate primary chromatic aberrations were successful. OCIS codes: 220.2740, 220.4830, 220.0220.

Byline: Werner Hilgers (1), Sandrine Faivre (2), Stephanie Chieze (3), Jerome Alexandre (4), Francois Lokiec (5), Francois Goldwasser (4), Eric Raymond (1), Carmen Kahatt (6,8), Abdelkrim Taamma (6), Garry Weems (7), John R. MacDonald (7), Jean-Louis Misset (1), Esteban Cvitkovic (6) Keywords: MGI 114; HMAF; platinum drugs; phase I trial; solid tumors; prostate cancer Abstract: Background: To determine maximum tolerated dose (MTD), recommended dose, safety and pharmacokinetics of irofulven combined with cisplatin in advanced solid tumor patients. Patients and methods: Cisplatin and irofulven were given sequentially i.v. over 30 min on day 1 and 15 every 4 weeks. Four dose levels (DL) were explored: irofulven (mg/kg)/cisplatin (mg/m.sup.2): DL1: 0.3/30 DL2: 0.4/30 DL3: 0.4/40 DL4: 0.5/40. Dose-limiting toxicity (DLT) included dosing omission and delay >1 week. MTD was the DL with DLT in 2/2 or a$?2/6 patients during cycle 1--2. Results: Between March 2002 and April 2003, 33 patients were treated. DLT occurred in 1/6 patients in DL1 (hypomagnesemia, hypocalcemia) 1/6 in DL2 (thrombocytopenia) 2 heavily pretreated patients out of 6 patients in DL3 (neutropenic infection, thrombocytopenia, stomatitis) 2/3 in DL4 (asthenia, blurred vision). Three DLT occurred in 12 additional patients treated at DL2. No toxic deaths occurred grade 4 toxicity and grade 3 non-hematological toxicity were infrequent. Six patients reported grade 1--2 visual events. Antitumor activity was observed over a broad spectrum of tumor types in all DLs: 1 partial response in bulky sarcoma (DL1) 1 clinical response in endometrial carcinoma (DL1) 2 partial responses not confirmed due to discontinuation (ovarian DL2, renal DL4) 8 stabilizations >3 months PSA response: 3/9 prostate cancer patients. Irofulven showed rapid elimination and high interpatient variability. Platinum and irofulven pharmacokinetics did not suggest drug-drug interactions. Conclusion: Irofulven with cisplatin was adequately tolerated and substantial evidence of antitumor activity was observed. The recommended dose is irofulven 0.4 mg/kg and cisplatin 30 mg/m.sup.2. Author Affiliation: (1) Hopital Saint-Louis, Paris, France (2) Institut Gustave Roussy, Villejuif, France (3) CHU La Miletrie, Poitiers, France (4) CHU Cochin, Paris, France (5) Centre Rene Huguenin, Saint-Cloud, France (6) CAC, Kremlin-Bicetre, France (7) MGI Pharma, Inc., Bloomington, MN, USA (8) Cvitkovic et Associes Consultants, 18-20 rue Pasteur, 94278, Kremlin-Bicetre, France Article History: Registration Date: 01/01/2005 Online Date: 28/01/2006 Article note: Supported by MGI PHARMA, INC., Bloomington, MN, USA. Work previously presented in part at the Annual Conference of the American Society for Clinical Oncology, Chicago, IL, 2003.

Byline: Robert P. Whitehead (1), Sheryl McCoy (2,10), John S. Macdonald (3), Saul E. Rivkin (4), Marcus A. Neubauer (5), Shaker R. Dakhil (6), Heinz-Josef Lenz (7), Michael S. Tanaka (8), James L. Abbruzzese (9) Abstract: Purpose: The purpose of this Phase II multi-institutional trial was to determine the efficacy and toxicity of R115777 in previously untreated patients with metastatic colorectal carcinoma. Patients and methods: Patients were required to have histologically confirmed colorectal cancer with distant metastatic disease that was not surgically curable. They could not have received prior chemotherapy for metastatic disease. R115777 was given at a dose of 300 mg p.o. twice a day for 21days every 28 days until tumor progression or toxicity or other reason for discontinuation occurred. The primary endpoint was to determine the confirmed response probability with this treatment. Results: There were 55 eligible patients accrued to the study. There were no complete responses, but one confirmed partial response for a confirmed response probability of 2% (95%CI 0--10%). Three additional patients had an unconfirmed partial response for an overall response probability of 7%. The time to treatment failure was 1.7 months and the estimated median survival was 8.1 months. One patient died of treatment related infection and there were 7 other patients with grade 4 toxicities consisting of neutropenia, leukopenia, febrile neutropenia and thrombocytopenia, depression, increased bilirubin, anemia, and pneumonitis/infiltrates. Conclusion: R115777 given as a single agent by this dose and schedule is ineffective in patients with metastatic colorectal cancer. Author Affiliation: (1) Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX (2) Southwest Oncology Group Statistical Center, Seattle, WA (3) St. Vincent's Comprehensive Cancer Center, New York, NY (4) Puget Sound Oncology Consortium, Seattle, WA (5) Kansas City Community Clinical Oncology Program, Kansas City, MO (6) Wichita Community Clinical Oncology Program, Wichita, KS (7) USC/Norris Comprehensive Cancer Center, Los Angeles, CA (8) University of California Davis Cancer Center, Sacramento, CA (9) University of Texas M.D. Anderson Cancer Center, Houston, TX (10) Operations Office, Southwest Oncology Group (SWOG-S9923), 14980 Omricon Drive, San Antonio, Texas, 78245-3217 Article History: Registration Date: 01/01/2005 Online Date: 28/01/2006

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jsat.2006.03.011 Byline: Christine Eibner (a), Andrew R. Morral (a), Rosalie Liccardo Pacula (b), John MacDonald (c) Keywords: DUI courts; Driving under the influence; Randomized experiment Abstract: We assessed the cost-effectiveness of the Rio Hondo driving-under-the-influence (DUI) court, a therapeutic court intervention in Los Angeles County targeted to repeat DUI offenders. The effectiveness of this court intervention was determined through a randomized controlled field experiment. Although prior research does not identify differences in alcohol-related or criminal behavior between treated and control individuals at follow-up, we found improvements in behavior for all program participants regardless of treatment status. A cost-minimization analysis found that, on average, costs of the DUI court exceeded traditional court expenditures for second-time offenders but produced cost savings for third-time offenders. This suggests that implementing a DUI-specific court intervention for serious DUI recidivists is a worthwhile investment of public resources. The unique legal treatment of DUI offenders in California may hide additional cost savings that could be accrued in other jurisdictions through the adoption of DUI court programs. Author Affiliation: (a) RAND Corporation, 1200 South Hayes Street, Arlington, VA 22202, USA (b) RAND Corporation and National Bureau of Economic Research, P.O. Box 2138, 1776 Main Street, Santa Monica, CA 90407-2138, USA (c) RAND Corporation, 1776 Main Street, Santa Monica, CA 90407-2138, USA Article History: Received 25 October 2005; Revised 20 March 2006; Accepted 22 March 2006

We assessed the cost-effectiveness of the Rio Hondo driving-under-the-influence (DUI) court, a therapeutic court intervention in Los Angeles County targeted to repeat DUI offenders. The effectiveness of this court intervention was determined through a randomized controlled field experiment. Although prior research does not identify differences in alcohol-related or criminal behavior between treated and control individuals at follow-up, we found improvements in behavior for all program participants regardless of treatment status. A cost-minimization analysis found that, on average, costs of the DUI court exceeded traditional court expenditures for second-time offenders but produced cost savings for third-time offenders. This suggests that implementing a DUI-specific court intervention for serious DUI recidivists is a worthwhile investment of public resources. The unique legal treatment of DUI offenders in California may hide additional cost savings that could be accrued in other jurisdictions through the adoption of DUI court programs. Keywords: DUI courts; Driving under the influence; Randomized experiment

Abstract Researchers at Delft University and the Robert H. Smith School of Business at the University of Maryland have developed the 'Global Supply Chain Game' (GSCG). A specific instance of [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.tins.2005.12.001 Byline: John F. MacDonald (a), Zhi-Gang Xiong (b), Michael F. Jackson (a) Abstract: Since the early 1960s it has been known that restoring extracellular Ca.sup.2+ following a period of low Ca.sup.2+ concentrations paradoxically causes an increase in intracellular Ca.sup.2+ levels that can lead to cell death. The mystery of this 'Ca.sup.2+ paradox' is made more intriguing by observations that lowering concentrations of extracellular Ca.sup.2+ and/or Mg.sup.2+ paradoxically enhances the entry of Ca.sup.2+ into hippocampal neurons. Until recently, the entry of Ca.sup.2+ through NMDA receptors was accepted as the major pathway leading to the excitotoxic, delayed cell death associated with the ischemic periods of stroke. Here, we discuss how several transient receptor potential (TRP) channels are likely to contribute to both the Ca.sup.2+ paradox and the delayed death of neurons following an ischemic stroke. Author Affiliation: (a) Departments of Physiology and Pharmacology, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada (b) Legacy Clinical Research, 1225 NE Second Avenue, Portland, OR 97232, USA

Since the early 1960s it has been known that restoring extracellular [Ca.sup.2+] following a period of low [Ca.sup.2+] concentrations paradoxically causes an increase in intracellular [Ca.sup.2+] levels that can lead to cell death. The mystery of this '[Ca.sup.2+] paradox' is made more intriguing by observations that lowering concentrations of extracellular [Ca.sup.2+] and/or [Mg.sup.2+] paradoxically enhances the entry of [Ca.sup.2+] into hippocampal neurons. Until recently, the entry of [Ca.sup.2+] through NMDA receptors was accepted as the major pathway leading to the excitotoxic, delayed cell death associated with the ischemic periods of stroke. Here, we discuss how several transient receptor potential (TRP) channels are likely to contribute to both the [Ca.sup.2+] paradox and the delayed death of neurons following an ischemic stroke.

Using a national survey of U.S. residents this study examines racial, socioeconomic, and community explanations for the trust of local police. We hypothesize that the construct of social capital offers a nexus for explaining racial differences in attitudes toward the police. We measure social capital as a construct by aggregating together measures that assess the degree of trust and civic engagement in communities. The results indicate that depleted levels of perceived community social capital contribute to higher levels of distrust of local police. Social capital, however, partially mediates the relative distrust of Blacks toward the police. These findings suggest only partial support for a social capital explanation of Blacks' distrust in the police. The implications of these findings for police reform efforts to mend minority relations in urban cities are discussed. Keywords: race: social capital: trust in police; civic participation

This study builds on existing criminological theories and examines the role of life satisfaction and self-control in explaining youth violence. Using data from a stratified cluster sample of 5,414 public high school students who responded to the South Carolina Youth Risk Behavior Survey, the study examines the relationship between adolescents' perceptions of life satisfaction, behavioral risky acts, and self-reported acts of violence. Analyses indicate that higher levels of life satisfaction are associated with lower violence. Participation in work and involvement in health-related risk-taking behaviors pertaining to sex, drugs, and alcohol are also associated with increased violence. The implications of these findings for criminological theory and for school-based violence prevention programs are discussed. Keywords: youth violence; life satisfaction; risk taking

Byline: Robert P. Whitehead (1), Jacqueline K. Benedetti (2), James L. Abbruzzese (3), Bach Ardalan (4), Stephen Williamson (5), Ellen R. Gaynor (6), Stanley P. Balcerzak (7), John S. Macdonald (8) Keywords: 5-FU; leucovorin; PALA; colorectal cancer; Phase II Abstract: Purpose: The purpose of this phase II multi-institutional study was to define the efficacy and toxicity of infusional 5-FU in combination with PALA and leucovorin in patients with advanced colorectal cancer. Patients and methods: Patients were required to have histologically confirmed colorectal cancer with distant metastases. The treatment regimen consisted of 5-FU 2600 mg/m.sup.2 as a 24-hours continuous infusion given once a week, concurrently with leucovorin (LV) at 500 mg/m.sup.2 as a 24-hour continuous infusion. PALA was administered 24 hours prior to 5-FU/LV at a dose of 250 mg/m.sup.2 iv over 15 minutes weekly. Patients were continued on the assigned treatment regimen until progression of disease, unacceptable toxicity, or the patient declined further therapy. Results: This study accrued 28 patients and all were eligible and evaluable for toxicity. Four patients had inadequate assessment of response and are considered non-responders. There was one complete response and five partial responses for an overall response rate of 6/28 or 21% (95% confidence interval 8--41%). Estimated median survival was 17.4 months (95% confidence interval 13.3--20.5 months). One patient died of a treatment related infection. This patient also had grade 4 diarrhea and vomiting. Conclusion: The combination of 5-FU, leucovorin, and PALA in the doses and schedule used here, produces a response rate similar to other modulated schedules of 5-FU with similar survival and toxicity profiles. Author Affiliation: (1) University of Texas Medical Branch, Galveston, TX (2) Southwest Oncology Group Statistical Center, Seattle, WA (3) University of Texas, MD Anderson Cancer Center, Houston, TX (4) University of Miami, School of Medicine, Miami, FL (5) University of Kansas Medical Center, Kansas City, KS (6) Loyola University Stritch School of Medicine, Maywood, IL (7) Ohio State University Health Center, Columbus, OH (8) St. Vincent's Comprehensive Cancer Center, New York, NY Article History: Registration Date: 02/10/2004

The behavior of water in silicalite and dealuminated zeolite is investigated. Molecular dynamics simulations using the Compass force field are used for this purpose.

Byline: Robert P. Whitehead (1), Jacqueline K. Benedetti (2), James L. Abbruzzese (3), Bach Ardalan (4), J. Wendall Goodwin (5), Stanley P. Balcerzak (6), Wolfram E. Samlowski (7), Heinz-Josef Lenz (8), John S. Macdonald (9) Keywords: 5-FU; leucovorin; PALA; pancreas cancer; phase II Abstract: Purpose: The purpose of this phase II multi-institutional study was to define the efficacy and toxicity of infusional 5-FU in combination with PALA and leucovorin in patients with advanced pancreatic cancer. Patients and methods: Patients were required to have histologically confirmed pancreatic cancer that was locally advanced, unresectable or disseminated. The treatment regimen consisted of weekly 5-FU 2600 mg/m.sup.2 given concurrently with leucovorin at 500 mg/m.sup.2. Both drugs were administered by 24-hour continuous infusion. PALA was administered 24 hours prior to the administration of 5-FU/LV at a dose of 250 mg/m.sup.2 IV over 15 minutes weekly. Patients were continued on the assigned treatment regimen until progression of disease, unacceptable toxicity, or the patient declined further therapy. Results: This study accrued 30 patients. Four of these patients were ineligible. All 26 eligible patients were evaluated for toxicity. One patient had inadequate assessment of response and was considered a non-responder. Three of the twenty-six eligible patients had partial responses, for a response rate of 12% (95% confidence interval 2% to 30%). All 26 eligible patients have died and the median overall survival was 7 months (95% confidence interval: 5.2 to 9 months). Four patients experienced grade 4 toxicities, including bilirubin increase (2 patients), vomiting (1 patient) and non-local skin ulceration (1). Two patients discontinued therapy due to toxicity. Conclusion: The dual modulation of 5-FU with PALA and leucovorin in the dose and schedule used here, has a response rate similar to other single agents in pancreatic cancer and can result in some long term survival while having relatively mild toxicity. Author Affiliation: (1) University of Texas Medical Branch, Galveston, TX (2) Southwest Oncology Group Statistical Center, Seattle, WA (3) University of Texas, MD Anderson Cancer Center, Houston, TX (4) School of Medicine, University of Miami, Miami, FL (5) Ozarks Regional Clinical Oncology Program, USA (6) Ohio State University Health Center, Columbus, OH (7) University of Utah Health Sciences Center, Salt Lake City, UT (8) University of Southern California School of Medicine, Los Angeles, CA (9) St. Vincent's Comprehensive Cancer Center, New York, NY Article History: Registration Date: 21/10/2004

The principal inhibitory neurotransmitter in the mammalian brain, [gamma]-aminobutyric acid (GABA), is thought to regulate memory processes by activating transient inhibitory postsynaptic currents. Here we describe a nonsynaptic, tonic form of inhibition in mouse CA1 pyramidal neurons that is generated by a distinct subpopulation of GABA type A receptors (GAB[A.sub.A]Rs). This tonic inhibitory conductance is predominantly mediated by [varies]5 subunit-containing GAB[A.sub.A]Rs([alpha]5GAB[A.sub.A]Rs) that have different pharmacological and kinetic properties compared to postsynaptic receptors. GABA[A.sub.A]Rs that mediate the tonic conductance are well suited to detect low, persistent, ambient concentrations of GABA in the extracellular space because they are highly sensitive to GABA and desensitize slowly. Moreover, the tonic current is highly sensitive to enhancement by amnestic drugs. Given the restricted expression of [alpha]5GAB[A.sub.A]Rs to the hippocampus and the association between reduced [alpha]5GAB[A.sub.A]R function and improved memory performance in behavioral studies, our results suggest that tonic inhibition mediated by [alpha]5GAB[A.sub.A]Rs in hippocampal pyramidal neurons plays a key role in cognitive processes.

In this article, the authors argue for the importance of a contextualized examination of racial profiling. Although the study of racial profiling has only begun, existing studies have typically examined this phenomenon at the state level and based on total population information gathered from high-patrol agencies. The authors argue that racial profiling is best understood within the spatial context of local areas rather than large geographical areas. The purpose of this article is to explore some theoretical avenues to investigating racial profiling within the community context by linking racial profiling to theoretical perspectives that highlight community-level processes. That is, the authors apply theories such as social disorganization, urban disadvantage/deprivation, and Sampson's community development and spatial diffusion arguments to the incident of racial profiling. The authors then illustrate the utility of exploring these linkages by providing information on crimes and structural dimensions in Miami-Dade County neighborhoods. Keywords: racial profiling; contexual analysis; urban disadvantage; spatial analysis

In recent years, much attention has been devoted to developing appropriate analytical methods to model criminal careers. Largely ignored in this methodological debate is the study of how the criminal behavior patterns of active offenders are related to individual characteristics. This article presents an analysis of the postrelease offending patterns of two cohorts of male youth released by the California Youth Authority in 1981 to 1982 and 1986 to 1987. The focus of the analysis is the frequency of arrest during the first three years following release. Negative binomial models are used to examine the relationship between a variety of factors that have been linked theoretically and empirically to the frequency of offending. Results suggest that measures of individual and geographic characteristics can be used to predict the average arrest frequencies and their variation among paroled youthful offenders. These findings suggest that there may be useful distinctions to be made among offending populations. Keywords: youthful offenders; negative binomial; criminal careers

Byline: Cynthia G. Leichman (1), Kari Chansky (2), John S. Macdonald (3), Michael A. Doukas (4), G. Thomas Budd (5), Jeffrey K. Giguere (6), James L. Abbruzzese (7) Keywords: 5-fluorouracil; dihydropyrimidine; dehydrogenase; colorectal cancer Abstract: Purpose. To investigate thehypothesis that a systemic agent designedto inhibit dihydropyrimidine dehydrogenase(DPD), the first enzyme in thefluoropyrimidine degradative pathway, couldimprove the effective amount of5-fluorouracil (5-FU) delivered to a tumorresulting in enhanced response. Patients and methods. Eligibility includedcytologically or pathologically verifieddiagnosis of colorectal cancer thatrecurred during or within 12 months ofcompletion of adjuvant therapy,representing patients generally consideredresistant to fluorinated pyrimidinetherapy. Stratification was into twocohorts: recurrence while receivingadjuvant therapy, and relapse within 12months of completing adjuvant therapy.Treatment consisted of 28 days of oraltherapy every five weeks with eniluraciland 5-FU administered in a 10:1 ratio. Thedaily dose of eniluracil was 10 [mg/m.sup.2]with 5-FU 1 mg/m.sup.2, divided into twodoses. Results. Twenty-five patientsare evaluable for response: 9 relapsedduring therapy and 16 relapsed within oneyear of adjuvant therapy. In the firstgroup, there was one partial response (9% 95% CI 0--41%) in the second cohort therewas one confirmed complete response (5% 95% CI 0--23%) and one unconfirmed partialresponse, for an overall response rate of10%. Conclusions. This regimen lackssignificant activity in this targetpopulation. Pre-treatment intratumoral DPDexpression was not assessed, therefore themechanism of fluorinated pyrimidineresistance cannot be specificallyattributed to elevated DPD levels.Attempting restoration of chemotherapysensitivity through blockade of enzymes orsignal transduction molecules responsiblefor resistance is rational, provided thattumor target expression is the basis fortrial entry. Author Affiliation: (1) Comprehensive Cancer Centers of the Desert, Palm Springs, CA, USA (2) Southwest Oncology Group Statistical Center, Seattle, WA, USA (3) St. Vincent's CCC, New York, NY, USA (4) University of Kentucky Medical Center, Lexington, KY, USA (5) Cleveland Clinic Foundation, Cleveland, OH, USA (6) Greenville CCOP, Greenville, SC, USA (7) MD Anderson Cancer Center, University of Texas, Houston, TX, USA Article History: Registration Date: 10/10/2004

Byline: Cary A. Presant (1,2,3), Joth Jacobson (1), Walter Wolf (4,5), Victor Waluch (4,5), Ilene C. Weitz (6), John S. Macdonald (7) Keywords: [.sup.19]F-MRS; intratumoral PK; 5-fluorouracil; leucovorin modulation Abstract: Purpose and design: We previouslydocumented that there was an associationbetween the intra-tumoral pharmacokinetics(TPK) of 5-FU and response to therapy with5-FU and leucovorin (p &lt .0001). Since wehave shown that other modulators of 5-FU,such as methotrexate, interferon andneutrexin alter its TPK, it was of interestto determine if the modulating effect ofleucovorin would also alter the tumoral PKof 5-FU. In order to determine the effectof leucovorin on intratumoral 5-FUpharmacokinetics, 23 patients (21evaluable) underwent 19.sup.F magneticresonance spectroscopy 19.sup.F-MRS)twice. The first 19.sup.F-MRS was following5-FU 600 mg/m.sup.2 alone, and the [second.sup.19]F-MRS was following by leucovorin500 mg/m.sup.2 and then 5-FU 600 mg/m.sup.2. Results: A comparison of theintratumoral 5-FU pharmacokineticsindicated that there was no general effectof leucovorin on the intratumoral half-lifeof 5-FU. In only two of these 21 patientswas the half-life of 5-FU altered, and inboth cases it was decreased by more than20%. Partial responses to 5-FU plusleucovorin therapy were seen only inpatients with a long intratumoral half-life(trapping) of 5-FU (3 PR in 11 patientswith T.sub.1/2 aY= 20 minutes, comparedto 0 PR in 11 patients with T.sub.1/2 &lt 20 minutes). There was a statisticallysignificant correlation between tumorresponse and the intratumoral T.sub.1/2 of5-FU, consistent with our prior results ina larger number of patients. However, therewas no statistically significantcorrelation of time-to-progression orsurvival with classification of thepatients into trappers or non-trappers,probably due to the small sample size inthis current study. Conclusion: The data reported hereare compatible with the hypothesis thatleucovorin enhancement of 5-fluorouracilantitumor responses is not mediated by thelevels of 5-FU in tumors, but rather, isdue to the modulation by leucovorin ofcellular metabolic processes that followthe uptake of free 5-FU into the tumorcell. The MRS technique may be useful inselected instances for elucidating thepossible metabolic interactions of drugsin vivo. Author Affiliation: (1) Southwest Oncology Group Statistical Center, Seattle, WA (2) California Cancer Medical Center, West Covina, CA (3) St. Vincent's CCC, New York, NY, USA (4) Los Angeles Oncologic Institute, St. Vincent Medical Center, Los Angeles, CA (5) Pharmacokinetic Imaging Program, University of Southern California, Los Angeles, CA, USA (6) California Cancer Medical Center, West Covina, CA, USA (7) St. Vincent's CCC, New York, NY, USA Article History: Registration Date: 10/10/2004

Elderly patients with colorectal cancer can benefit from surgery followed by chemotherapy without an increased risk of side effects. This was the conclusion of researchers who analyzed seven clinical trials covering 3,351 patients.

This article discusses the relationship between length of voyage and mortality during the middle passage of nine different routes in the slave trade during the 18th and 19th centuries; on-board crowding, season of departure, and stop overs are all taken into account. The authors calculate death rates to determine whether they occurred in the early, middle or late stages of the voyage, finding that deaths were due mainly to pre-boarding and on board conditions; the connection between slave and crew deaths is also explored.