Intake Fraction Variability Between Air Pollution Emission Sources Inside an Urban Area

The cost‐effective mitigation of adverse health effects caused by air pollution requires information on the contribution of different emission sources to exposure. In urban areas the exposure potential of different sources may vary significantly depending on emission height, population density, and other factors. In this study, we quantified this intraurban variability by predicting intake fraction (iF) for 3,066 emission sources in Warsaw, Poland. iF describes the fraction of the pollutant that is inhaled by people in the study area. We considered the following seven pollutants: particulate matter (PM), nitrogen oxides (NO_x), sulfur dioxide (SO₂), benzo[a] pyrene (BaP), nickel (Ni), cadmium (Cd), and lead (Pb). Emissions for these pollutants were grouped into four emission source categories (Mobile, Area, High Point, and Other Point sources). The dispersion of the pollutants was predicted with the CALPUFF dispersion model using the year 2005 emission rate data and meteorological records. The resulting annual average concentrations were combined with population data to predict the contribution of each individual source to population exposure. The iFs for different pollutant‐source category combinations varied between 51 per million (PM from Mobile sources) and 0.013 per million (sulfate PM from High Point sources). The intraurban iF variability for Mobile sources primary PM emission was from 4 per million to 100 per million with the emission‐weighted iF of 44 per million. These results propose that exposure due to intraurban air pollution emissions could be decreased more effectively by specifically targeting sources with high exposure potency rather than all sources.     

An optimal search procedure

Consider the following problem. There are exactly two defective (unknown) elements in the set X={x₁, x₂,…,x_n}, all possibilities occuring with equal probabilities. We want to identify the unknown (defective) elements by testing some subsets A of X, and for each such set A determining whether A contains any of them. The test on an individual subset A informs us that either all elements of the tested set A are good, or that at least one of them is defective (but we do not know which ones or how many). A set containing at least one defective element is said to be defective. Our aim is to minimize the maximal number of tests. For the optimal strategy, let the maximal test length be denoted by l₂(n). We obtain the value of this function for an infinite sequence of values of n.     

Selection and implementation of a PPC system

There are many computer-aided production planning and control (PPC) systems available on the market which can provide a solution to the complex task of production planning and control. However, the question remains, how can a company find an optimal system from the vast amount of available systems? This article proposes that a company, having decided to buy one of the available systems, starts a project for selection and implementation of the PPC system.     

Capturing change: Doing research in a society undergoing transformation

Systematic review and synthesis methods have gained wide acceptance within the social sciences and, as a result, many postgraduate students now consider using them for their thesis or dissertation research. However, students are rarely aware of all the concrete implications that their decision entails. This reflective narrative reports the experience of a political science student who began to conduct a systematic review as part of his Ph.D. dissertation but who did not complete it. The aim of this article is to identify challenges and lessons learned from this experience and to formulate recommendations for postgraduate students who wish to make an informed choice with respect to the use of these methods.     

What Really Happens in Kobylians’ka’s Land,and Why It Matters

Since the publication of OlTia Kobylians’ka’s novel Zemlia (Land, 1902), the consensus of Ukrainian critics and scholars, both non-Soviet and Soviet, has held that the novel’s central event, and the element of the plot offering the main challenge to interpretation, is the murder of a young peasant by his brother. Attentive reading, however, reveals that the murder is constructed in the novel as a deed whose perpetrator remains unknown. Readings of the novel as an illustration of social or psychological causation in human affairs corresponded to the predispositions of populist critics of various periods. Readings more respectful of the text, and more in keeping with Kobylians’ka’s oeuvre as a whole, need to acknowledge that the world-view consistent with the novel is one that despairs of demonstrable causes. Narrative voice and implied readership in Land are managed so as to exclude the construct of an omniscient narrator authorizing a final, knowable version of past events. Instead, the novel may be seen as reflecting upon the irrationality of diverse models for explaining human behaviour. Common-sense social and psychological notions of causality are found inadequate to explain the murder in Land, as are racial determinism, accident, divine intervention, and the Nietzsche-inspired model of humankind as divided into strong and weak, free and enslaved.     

Editorial statement: Stress and work compensation

Shift work has been reported to predict health problems, and a possible explanation is that shift work may lead to poorer health habits, thereby increasing a person's vulnerability to illness. This study examined the association between shift work and health habits, as indicated by smoking, alcohol intake, physical activity and by being overweight. A questionnaire was sent to all 2795 female nurses working in the 10 hospitals of two Finnish health care districts. From the 2299 respondents, we selected those 506 shift workers who reported having always done shift work and those 183 day workers who had never done shift work. Shift workers were found to smoke more and to be overweight more often than day workers. These differences gradually increased in each successive age group, being 1.94 pack-years in smoking and 0.9 kg m^-2 in body mass index among nurses over 45 years of age. Shift work was not associated with alcohol intake or sedentary lifestyle. This evidence is compatible with the possibility that shift work in nurses increases smoking and being overweight to a degree that contributes to health problems, including coronary heart disease.     

Is tolerance to shiftwork predictable from individual difference measures?

Abstract

This study was aimed at evaluating the most important relations between individual characteristics of shiftworkers and their subjective health complaints, obtained by cross-sectional and longitudinal procedures. A total of 604 shiftworkers and 185 young subjects who were going to enter shiftwork were examined by means of individual difference and subjective health questionnaires. The questionnaires were administered concurrently to the group of workers already involved in shiftwork. In the other group studied, the questionnaires were administered before they entered shiftwork, and subjective health was re-examined after the first and third year of work on shifts. More health complaints were reported by the group of older workers and those with longer shiftwork experience, with higher scores of neuroticism, hard-driving and competitiveness, speed and impatience, and rigidity of sleeping habits, and lower scores on relaxedness, efficiency and vigorousness. However, the correlations between these dimensions, when taken before entering shiftwork, and subjective health complaints obtained after a few years working on shifts were small or absent, indicating low validity of the individual difference measures for predicting subsequent health problems in shiftworkers.