Modeling effects of urban heat island mitigation strategies on heat-related morbidity: a case study for Phoenix, Arizona, USA

A zero-dimensional energy balance model was previously developed to serve as a user-friendly mitigation tool for practitioners seeking to study the urban heat island (UHI) effect. Accordingly, this established model is applied here to show the relative effects of four common mitigation strategies: increasing the overall (1) emissivity, (2) percentage of vegetated area, (3) thermal conductivity, and (4) albedo of the urban environment in a series of percentage increases by 5, 10, 15, and 20% from baseline values. In addition to modeling mitigation strategies, we present how the model can be utilized to evaluate human health vulnerability from excessive heat-related events, based on heat-related emergency service data from 2002 to 2006. The 24-h average heat index is shown to have the greatest correlation to heat-related emergency calls in the Phoenix (Arizona, USA) metropolitan region. The four modeled UHI mitigation strategies, taken in combination, would lead to a 48% reduction in annual heat-related emergency service calls, where increasing the albedo is the single most effective UHI mitigation strategy.     

Ethnic differences in risk of compulsory psychiatric admission among representative cases of psychosis in London.

OBJECTIVE--To compare the risk of detention under the Mental Health Act 1983 in a representative group of people with psychotic disorders from different ethnic groups. SETTING--Two defined geographical areas in south London. DESIGN--Annual period prevalent cases of psychosis were identified in 1993 in the study areas from hospital and community data. Standardised criteria were applied to case notes to establish diagnosis and detention under the act. SUBJECTS--535 patients were identified, of whom 439 fulfilled ICD-10 criteria for psychosis. MAIN OUTCOME MEASURES--Risk of ever having been detained under the Mental Health Act 1983, risk of detention under specific sections of the act during the study year, and risk of contact with forensic services for the different ethnic groups. RESULTS--439 patients with a psychotic illness were identified. Nearly half of the white patients had been detained under the act compared with 70% and 69% of black Caribbean and black African patients, respectively. Black Caribbean and black African patients were more likely than white patients to have been involuntarily detained (adjusted odds ratio 3.67; 95% confidence interval 2.07 to 6.50 and 2.88; 1.04 to 7.95, respectively). Rates of use of sections 2, 3 and 136 in the study year were higher for black than for white patients, and black patients were more likely than white patients to have been admitted to a psychiatric intensive care facility or prison. CONCLUSION--Independent of psychiatric diagnosis and sociodemographic differences, black African and black Caribbean patients with psychosis in south London were more likely than white patients to have ever been detained under the Mental Health Act 1983.