Cold and heat waves in the United States

Extreme cold and heat waves, characterised by a number of cold or hot days in succession, place a strain on people’s cardiovascular and respiratory systems. The increase in deaths due to these waves may be greater than that predicted by extreme temperatures alone. We examined cold and heat waves in 99 US cities for 14 years (1987–2000) and investigated how the risk of death depended on the temperature threshold used to define a wave, and a wave’s timing, duration and intensity. We defined cold and heat waves using temperatures above and below cold and heat thresholds for two or more days. We tried five cold thresholds using the first to fifth percentiles of temperature, and five heat thresholds using the ninety-fifth to ninety-ninth percentiles. The extra wave effects were estimated using a two-stage model to ensure that their effects were estimated after removing the general effects of temperature. The increases in deaths associated with cold waves were generally small and not statistically significant, and there was even evidence of a decreased risk during the coldest waves. Heat waves generally increased the risk of death, particularly for the hottest heat threshold. Cold waves of a colder intensity or longer duration were not more dangerous. Cold waves earlier in the cool season were more dangerous, as were heat waves earlier in the warm season. In general there was no increased risk of death during cold waves above the known increased risk associated with cold temperatures. Cold or heat waves earlier in the cool or warm season may be more dangerous because of a build up in the susceptible pool or a lack of preparedness for cold or hot temperatures.

A cross-sectional analysis of patterns of obesity in a cohort of working nurses and midwives in Australia, New Zealand, and the United Kingdom

Objective The aim of this study was to examine the prevalence of overweight and obesity and the association with demographic, reproductive work variables in a representative cohort of working nurses and midwives. Design A cross sectional study of self reported survey data. Settings Australia, New Zealand and the United Kingdom. Methods Measurement outcomes included BMI categories, demographic (age, gender, marital status, ethnicity), reproductive (parity, number of births, mother's age at first birth, birth type and menopausal status) and workforce (registration council, employment type and principal specialty) variables. Participants 4996 respondents to the Nurses and Midwives e-Cohort study who were currently registered and working in nursing or midwifery in Australia (n=3144), New Zealand (n=778) or the United Kingdom (n=1074). Results Amongst the sample 61.87% were outside the healthy weight range and across all three jurisdictions the prevalence of obesity in nurses and midwives exceeded rates in the source populations by 1.73% up to 3.74%. Being overweight or obese was significantly associated with increasing age (35–44 yrs aOR 1.71, 95% CI 1.41–2.08; 45–55 yrs aOR 1.90, 95%CI 1.56–2.31; 55–64 aOR 2.22, 95% CI 1.71–2.88), and male gender (aOR 1.46, 95% CI 1.15–1.87). Primiparous nurses and midwives were more likely to be overweight or obese (aOR 1.37, 95% CI 1.06–1.76) as were those who had reached menopause (aOR 1.37, 95% CI 1.11–1.69). Nurses and midwives in part-time or casual employment had significantly reduced risk of being overweight or obese, (aOR 0.81, 95% CI 0.70–0.94 and aOR 0.75, 95% CI 0.59–0.96 respectively), whilst working in aged carried increased risk (aOR 1.37, 95% CI 1.04–1.80). Conclusion Nurses and midwives in this study have higher prevalence of obesity and overweight than the general population and those who are older, male, or female primiparous and menopausal have significantly higher risk of overweight or obesity as do those working fulltime, or in aged care. The consequences of overweight and obesity in this occupational group may impact on their workforce participation, their management of overweight and obese patients in their care as well as influencing their individual health behaviours and risks of occupational injury and chronic disease.

Individual, environmental, and meteorological predictors of daily personal ultraviolet radiation exposure measurements in a United States cohort study

Background Individual exposure to ultraviolet radiation (UVR) is challenging to measure, particularly for diseases with substantial latency periods between first exposure and diagnosis of outcome, such as cancer. To guide the choice of surrogates for long-term UVR exposure in epidemiologic studies, we assessed how well stable sun-related individual characteristics and environmental/meteorological factors predicted daily personal UVR exposure measurements. Methods We evaluated 123 United States Radiologic Technologists subjects who wore personal UVR dosimeters for 8 hours daily for up to 7 days (N = 837 days). Potential predictors of personal UVR derived from a self-administered questionnaire, and public databases that provided daily estimates of ambient UVR and weather conditions. Factors potentially related to personal UVR exposure were tested individually and in a model including all significant variables. Results The strongest predictors of daily personal UVR exposure in the full model were ambient UVR, latitude, daily rainfall, and skin reaction to prolonged sunlight (R2 = 0.30). In a model containing only environmental and meteorological variables, ambient UVR, latitude, and daily rainfall were the strongest predictors of daily personal UVR exposure (R2 = 0.25). Conclusions In the absence of feasible measures of individual longitudinal sun exposure history, stable personal characteristics, ambient UVR, and weather parameters may help estimate long-term personal UVR exposure.

[Book Review] Urban Maps : Instruments of Narrative and Interpretation in the City by Richard Brook and Nick Dunn, Ashgate, Farham, United Kingdom, 2011, 250pp. ISBN 978-0-754676-5-77.

Urban maps discusses new ways and tools to read and navigate the contemporary city. Each chapter investigates a possible approach to unravel the complexity of contemporary urban forms. Each tool is first defined, introducing its philosophical background, and is then discussed with case studies, showing its relevance for the navigation of the built environment. Urbanism classics such as the work of Lynch, Jacobs, Venuti and Scott-Brown, Lefebrve and Walter Benjamin are fundamental in setting the framework of the volume. In the introduction cities and mapping are first discussed, the former are illustrated as ‘a composite of invisible networks devoid of landmarks and overrun by nodes’ (p. 3), and ‘a series of unbounded spaces where mass production and mass consumption reproduce a standardised quasi-global culture’ (p. 6).

Female concentration and the gender wage differential in the United Kingdom

The paper utilizes the methodology proposed by Johnson and Solon (American Economic Review, 76 (5), 1117-1125, 1986) to examine the impact of job segregation on the gender wage gap in the UK in 1991. The results suggest that despite implementation of the UK 1983 Equal Pay Amendment there remains clear evidence that male/female workers in female dominated jobs continue to earn less for work of ‘similar worth’ than their counterparts in male dominated jobs within the same firm. This conclusion is insensitive to whether one adopts an occupation or firm based measure of gender concentration.

Bike share's impact on car use : evidence from the United States, Great Britain, and Australia

There are currently more than 400 cities operating bike share programs. Purported benefits of bike share programs include flexible mobility, physical activity, reduced congestion, emissions and fuel use. Implicit or explicit in the calculation of program benefits are assumptions regarding the modes of travel replaced by bike share journeys. This paper examines the degree to which car trips are replaced by bike share, through an examination of survey and trip data from bike share programs in Melbourne, Brisbane, Washing, D.C., London, and Minneapolis/St. Paul. A secondary and unique component of this analysis examines motor vehicle support services required for bike share fleet rebalancing and maintenance. These two components are then combined to estimate bike share’s overall contribution to changes in vehicle kilometres traveled. The results indicate that the estimated mean reduction in car use due to bike share is at least twice the distance covered by operator support vehicles, with the exception of London, in which the relationship is reversed, largely due to a low car mode substitution rate. As bike share programs mature, evaluation of their effectiveness in reducing car use may become increasingly important. This paper reveals that by increasing the convenience of bike share relative to car use and by improving perceptions of safety, the capacity of bike share programs to reduce vehicle trips and yield overall net benefits will be enhanced. Researchers can adapt the analytical approach proposed in this paper to assist in the evaluation of current and future bike share programs.

Air navigation services in Australia and the United States : a comparative case study

The central document governing the global organization of Air Navigation Services (ANS) is the Convention on International Civil Aviation, commonly referred to as the “Chicago Convention,” whose original version was signed in that city in 1944. In the Convention, Contracting States agreed to ensure the minimum standards of ANS established by ICAO, a specialized United Nations agency created by the Convention. Emanating from obligations under the Chicago Convention, ANS has traditionally provided by departments of national governments. However, there is a widespread trend toward transferring delivery of ANS services outside of line departments of national governments to independent agencies or corporations. The Civil Air Navigation Services Organisation (CANSO), which is the trade association for independent ANS providers, currently counts approximately 60 members, and is steadily growing. However, whatever delivery mechanisms are chosen, national governments remain ultimately responsible for ensuring that adequate ANS services are available. The provision by governments of ANS reflects the responsibility of the state for safety, international relations, and indirectly, the macroeconomic benefits of ensuring a sound infrastructure for aviation. ANS is a “public good” and an “essential good” provided to all aircraft using a country’s airfields and airspace. However, ANS also represents a service that directly benefits only a limited number of users, notably aircraft owners and operators. The idea that the users of the system, rather than the taxpaying public, should incur the costs associated with ANS provision is inherent in the commercialization process. However, ICAO sets out broad principles for the establishment of user charges, which member states are expected to comply with. ICAO states that only distance flown and aircraft weights are acceptable parameters for use in a charging system. These two factors are considered to be easy to measure, bear a reasonable relationship to the value of service received, and do not discriminate due to factors such as where the flight originated or the nation of aircraft registration.

'Look and feel' computer copyright in the United States and Australia (part 2)

Australian law similar to that of United States -- Australian law requires copyright must subsist in plaintiff's material and defendent's work must infringe plaintiff's copyright to find defendent liable for illegal copying -- subsistence -- infringement -- two cases that touch on 'look and feel' issue -- passing-off -- look and feel of computer program deserves protection

'Look and feel' computer copyright in the United States and Australia (part 1)

United States copyright law -- two streams of computer copyright cases form basis for 'look and feel' litigation, literary work stream and audiovisual work stream -- literary work stream focuses on structure -- audiovisual work steam addresses appearance -- case studies

Bike share's impact on car use : evidence from the United States, Great Britain, and Australia

There are currently more than 700 cities operating bike share programs. Purported benefits of bike share include flexible mobility, physical activity, reduced congestion, emissions and fuel use. Implicit or explicit in the calculation of program benefits are assumptions regarding the modes of travel replaced by bike share journeys. This paper examines the degree to which car trips are replaced by bike share, through an examination of survey and trip data from bike share programs in Melbourne, Brisbane, Washington, D.C., London, and Minneapolis/St. Paul. A secondary and unique component of this analysis examines motor vehicle support services required for bike share fleet rebalancing and maintenance. These two components are then combined to estimate bike share’s overall contribution to changes in vehicle kilometers traveled. The results indicate an estimated reduction in motor vehicle use due to bike share of approx. 90,000 km per annum in Melbourne and Minneapolis/St. Paul and 243,291 km for Washington, D.C. London’s bike share program however recorded an additional 766,341 km in motor vehicle use. This was largely due to a low car mode substitution rate and substantial truck use for rebalancing of bicycles. As bike share programs mature, evaluation of their effectiveness in reducing car use may become increasingly important. Researchers can adapt the analytical approach proposed in this paper to assist in the evaluation of current and future bike share programs.