Combining QMRA and Epidemiology to Estimate Campylobacteriosis Incidence

The disease burden of pathogens as estimated by QMRA (quantitative microbial risk assessment) and EA (epidemiological analysis) often differs considerably. This is an unsatisfactory situation for policymakers and scientists. We explored methods to obtain a unified estimate using campylobacteriosis in the Netherlands as an example, where previous work resulted in estimates of 4.9 million (QMRA) and 90,600 (EA) cases per year. Using the maximum likelihood approach and considering EA the gold standard, the QMRA model could produce the original EA estimate by adjusting mainly the dose‐infection relationship. Considering QMRA the gold standard, the EA model could produce the original QMRA estimate by adjusting mainly the probability that a gastroenteritis case is caused by Campylobacter. A joint analysis of QMRA and EA data and models assuming identical outcomes, using a frequentist or Bayesian approach (using vague priors), resulted in estimates of 102,000 or 123,000 campylobacteriosis cases per year, respectively. These were close to the original EA estimate, and this will be related to the dissimilarity in data availability. The Bayesian approach further showed that attenuating the condition of equal outcomes immediately resulted in very different estimates of the number of campylobacteriosis cases per year and that using more informative priors had little effect on the results. In conclusion, EA was dominant in estimating the burden of campylobacteriosis in the Netherlands. However, it must be noted that only statistical uncertainties were taken into account here. Taking all, usually difficult to quantify, uncertainties into account might lead to a different conclusion.     

Metaphors of Protest: A Classification of Motivations for Collective Action

This article proposes a classification of motivations for collective action based in three of Tetlock's (2002) metaphors of social functionalism (i.e., people as intuitive economists, politicians, and theologians). We use these metaphors to map individual- and group-based motivations for collective action from the literature onto the distinction between individuals who are strongly or weakly identified with their social group. We conclude that low identifiers can be best understood as intuitive economists (supported by both early and recent work on collective action), whereas high identifiers can be best thought of as intuitive politicians or theologians (as recent work on social identity has started to explore). Interestingly, our classification reveals a remarkable lack of attention for the intuitive theologian's motivation for collective action. We therefore develop new hypotheses for future research, and derive recommendations for policy and practice from our analysis.     

Quantitative Risk Estimation for a Legionella pneumophila Infection Due to Whirlpool Use

Quantitative microbiological risk assessment was used to quantify the risk associated with the exposure to Legionella pneumophila in a whirlpool. Conceptually, air bubbles ascend to the surface, intercepting Legionella from the traversed water. At the surface the bubble bursts into dominantly noninhalable jet drops and inhalable film drops. Assuming that film drops carry half of the intercepted Legionella, a total of four (95% interval: 1–9) and 4.5×10⁴ (4.4×10⁴ – 4.7×10⁴) cfu/min were estimated to be aerosolized for concentrations of 1 and 1,000 legionellas per liter, respectively. Using a dose‐response model for guinea pigs to represent humans, infection risks for active whirlpool use with 100 cfu/L water for 15 minutes were 0.29 (～0.11–0.48) for susceptible males and 0.22 (～0.06–0.42) for susceptible females. A L. pneumophila concentration of ≥1,000 cfu/L water was estimated to nearly always cause an infection (mean: 0.95; 95% interval: 0.9–～1). Estimated infection risks were time‐dependent, ranging from 0.02 (0–0.11) for 1‐minute exposures to 0.93 (0.86–0.97) for 2‐hour exposures when the L. pneumophila concentration was 100 cfu/L water. Pool water in Dutch bathing establishments should contain <100 cfu Legionella/L water. This study suggests that stricter provisions might be required to assure adequate public health protection.     

Optimal allocation of time points for the random effects model

In this article the problem of the optimal selection and allocation of time points in repeated measures experiments is considered. D‐ optimal designs for linear regression models with a random intercept and first order auto‐regressive serial correlations are computed numerically and compared with designs having equally spaced time points. When the order of the polynomial is known and the serial correlations are not too small, the comparison shows that for any fixed number of repeated measures, a design with equally spaced time points is almost as efficient as the D‐ optimal design. When, however, there is no prior knowledge about the order of the underlying polynomial, the best choice in terms of efficiency is a D‐ optimal design for the highest possible relevant order of the polynomial. A design with equally‐spaced time points is the second best choice     

Peeping at peers: a cross-national study of professionalism in social work

Comparative studies of social work are a neglected field, but demands for them are increasing.

These were the opening words of an interesting article by Anne Meeuwisse and Hans Swärd which was published in an earlier issue of this journal (Meeuwisse and Swärd 2007). In their article, Meeuwisse and Swärd discuss three ways of making cross-national comparisons of social work. These ways are comparisons based on models of social policy, profession-orientated comparisons and practice-orientated comparisons. Generally, these three ways of comparisons move from a macro-level to a micro-level and all three ways have their own strengths and weaknesses. Since the subject of my PhD study happens to be a cross-national comparative study of social work, I considered it insightful and relevant to illustrate my own research plan here. The aim in doing so is twofold. First, to contribute to the field of comparative studies of social work, which is a neglected field indeed; second, it is my hope that this article will yield useful reactions from readers.     

Uncertainty of Population Risk Estimates for Pathogens Based on QMRA or Epidemiology: A Case Study of Campylobacter in the Netherlands

Epidemiology and quantitative microbiological risk assessment are disciplines in which the same public health measures are estimated, but results differ frequently. If large, these differences can confuse public health policymakers. This article aims to identify uncertainty sources that explain apparent differences in estimates for Campylobacter spp. incidence and attribution in the Netherlands, based on four previous studies (two for each discipline). An uncertainty typology was used to identify uncertainty sources and the NUSAP method was applied to characterize the uncertainty and its influence on estimates. Model outcomes were subsequently calculated for alternative scenarios that simulated very different but realistic alternatives in parameter estimates, modeling, data handling, or analysis to obtain impressions of the total uncertainty. For the epidemiological assessment, 32 uncertainty sources were identified and for QMRA 67. Definitions (e.g., of a case) and study boundaries (e.g., of the studied pathogen) were identified as important drivers for the differences between the estimates of the original studies. The range in alternatively calculated estimates usually overlapped between disciplines, showing that proper appreciation of uncertainty can explain apparent differences between the initial estimates from both disciplines. Uncertainty was not estimated in the original QMRA studies and underestimated in the epidemiological studies. We advise to give appropriate attention to uncertainty in QMRA and epidemiological studies, even if only qualitatively, so that scientists and policymakers can interpret reported outcomes more correctly. Ideally, both disciplines are joined by merging their strong respective properties, leading to unified public health measures.     

Modular Network Design: Using Information and Communication Technology to Allocate Production Tasks in a Virtual Organization*

The increased interest in customer service and the trend towards customization gives rise to new organizational forms such as the virtual organization. This paper introduces the Modular Network Design (MND) approach to complement Mowshowitz' (1997) theory of virtual organization. This theory focuses on metamanagement of the virtual organization and consists of four activities: (1) determine and analyze customer requirements, (2) track the possibilities for satisfying these requirements, (3) develop and allocate production tasks among the members of the virtual organization, and (4) assess and adjust tasks and allocation procedures. The MND approach elaborates on this theory by breaking down both the requirements and the production tasks into modular entities, and by measuring the performance of the resulting virtual network in terms of operating costs and throughput time. The major contribution of the MND approach lies in its ability to support the assessment of alternative allocations of production tasks among the members of a virtual organization, using Information and Communication Technology (ICT) as enabler. The assessment of such alternative designs is illustrated by an application of MND in the air cargo industry. The results show how the virtual organization and its members can realize significant improvements in operating costs and throughput times when applying ICT to link and reallocate their modular production tasks in response to customized orders.     

How What We See and What We Know Influence Iconic Gesture Production

In face-to-face communication, speakers typically integrate information acquired through different sources, including what they see and what they know, into their communicative messages. In this study, we asked how these different input sources influence the frequency and type of iconic gestures produced by speakers during a communication task, under two degrees of task complexity. Specifically, we investigated whether speakers gestured differently when they had to describe an object presented to them as an image or as a written word (input modality) and, additionally, when they were allowed to explicitly name the object or not (task complexity). Our results show that speakers produced more gestures when they attended to a picture. Further, speakers more often gesturally depicted shape information when attended to an image, and they demonstrated the function of an object more often when they attended to a word. However, when we increased the complexity of the task by forbidding speakers to name the target objects, these patterns disappeared, suggesting that speakers may have strategically adapted their use of iconic strategies to better meet the task’s goals. Our study also revealed (independent) effects of object manipulability on the type of gestures produced by speakers and, in general, it highlighted a predominance of molding and handling gestures. These gestures may reflect stronger motoric and haptic simulations, lending support to activation-based gesture production accounts.     

Against exceptionalism: the legitimacy of the neoliberal age

ABSTRACT

After the financial crisis of 2007–08, many commentators, adopting a broadly Polanyian logic of reasoning, expected a departure from neoliberalism. The failure of this shift to materialize has typically been accounted for in ‘exceptionalist’ terms: the persistence of neoliberalism is understood not as a function of a specific legitimacy it has itself engendered, but in terms of external interventions by elites who manage to ‘capture’ executive and regulatory institutions and so to bypass democratic pressures. This paper argues that such an approach underestimates the endogenous sources of legitimacy and resilience that neoliberal governance commands. It criticizes the idea that neoliberalism is at its core dependent on a Schmittian exceptionalism and suggests a perspective on Hayek's articulation of neoliberalism that dissociates it from such an exceptionalist approach. The article proceeds to interrogate the rationality of neoliberalism by examining its distinctively secular temporal logic, rooted in speculation, preemption and reaction.     

Ethnic Composition and School Performance in the Secondary Education of Turkish Migrant Students in Seven Countries and 19 European Educational Systems

This article examines the effect of the ethnic composition on school performances in secondary education for Turkish students, using both cross‐national and Swiss national PISA 2009 data. At the school level our results show no effect of the proportion of natives or the proportion of coethnics and a negative association between ethnic diversity (we employ a residualized score of diversity on the proportion of migrants) and math performances. Consequently, we find no evidence for social capital advantages and an indication of barriers. Finally, we find no association between social capital variables on national or educational system level and math performance.