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•We reviewed studies on atmospheric dispersion modelling of pathogenic bioaerosols with a special focus on risk assessment.•The type of model depends on the spatial scale, the complexity, and the preference for forward or backward analysis.•A major drawback of many studies was the lack of quantitative analyses.•We recommend including quantified emission and inactivation rates and a dosimetry and dose-response model in ADM studies.

An architecture is proposed for agents to coordinate formation and execution of plans. Along with the architecture, a new coordination language is introduced that agents may employ to form temporary alliances for planning and plan execution. This language is based on ideas from constraint programming and a formal operational semantics is given for it.

Abstract: We implement a specific protocol for bit exchange among card-playing agents in three different state-of-the-art epistemic model checkers and compare the results. [Copyright &y& Elsevier]

Apart from symptomology, there are very few reports on lung function following exposure to low levels of organophosphate (OP) pesticides in man. Twenty-five occupationally exposed farmers and 22 environmentally exposed freshwater fishermen were evaluated between and during OP spray seasons. Forty marine fishermen living away from agricultural areas were recruited as a control group. Forced vital capacity (FVC) and forced expiratory volume in the first second (FEV"1) were measured by spirometry. Haemoglobin corrected erythrocyte acetylcholinesterase (AChE) levels were measured during and between (baseline estimation) spray seasons using a portable WHO-approved Test-mate system (EQM Research, Ohio). FVC ratio was lower in the farmers as compared to the controls (P<0.001) between exposure seasons. In the farmers, FVC ratio decreased further during the exposure season (P=0.023). FEV"1 was lower in the farmers as compared to the controls in both periods (P<0.05). In the fishermen, the decrease in ratios of FVC and FEV"1 following exposure to pesticides was not significant. FEV"1/FVC ratios were similar in the three groups between (P=0.988) and during (P=0.159) exposure periods. Following exposure to OPs, AChE levels dropped 12.75% in the farmers (P<0.001) and 5.62% in the freshwater fishermen (P=0.001). Occupational exposure to OP results in restrictive lung dysfunction, a phenomenon not observed following environmental exposure.

A study of the cost of malaria at the household level, community perceptions, preventive measures and illness behaviour linked to the disease was undertaken in 5 villages in the dry zone of Sri Lanka. The surveyed community had a high knowledge of malaria, although side effects of antimalarial drugs were often confused with symptoms of the disease. The community sought prompt diagnosis and treatment at ‘western-type’ facilities, with 84% making use of government facilities as their first choice and 16% preferring private facilities. The preventive measures used were burning coils (54% of families) and special leaves (69% of families), and 93% of the families had their houses sprayed with insecticides. Average direct expenditure on a single malaria episode was US$3, with some families spending more than 10% of the annual household net income per episode. The highest expenditure was on special diets for the sick person, to neutralize the perceived heating effect of the disease and its treatment.

We present a formal system to reason about and specify the behavior of multiple intelligent artificial agents. Essentially, each agent can perform certain actions, and it may possess a variety of information in order to reason about its and other agent's actions. Thus, our KARO-framework tries to deal formally with the notion of Knowledge, possessed by the agents, and their possible execution of actions. In particular, each agent may reason about its —or, alternatively, other's— Abilities to perform certain actions, the possible Results of such an execution and the availability of the Opportunities to take a particular action. Formally, we combine dynamic and epistemic logic into one modal system, and add the notion of ability to it. We demonstrate that there are several options to define the ability to perform a sequentially composed action, and we outline several properties under two alternative choices. Also, the agents' views on the correctness and feasibility of their plans are highlighted. Finally, the complications in the completeness proof for both systems indicate that the presence of abilities in the logic makes the use of infinite proof rules useful, if not inevitable.

Environmental and socioeconomic risk factors for malaria were studied in a village in Sri Lanka. Over a period of one year, all 49 households in the village were visited every alternate day to obtain information on malaria episodes. Information on risk factors was obtained through questionnaires and direct observations. Age below 17 years (relative risk [RR] = l·66, 95% confidence interval [95% CI] 1·18–2·35), use of bed nets (RR = 0·16, 95% CI 0·05–0·45) and traditional fumigants (RR = 0·58, 95% CI 0·37–0·93) were independent predictors of malaria. People using anti-mosquito pyrethrum coils had a higher risk for malaria than people living in houses where they were not used (RR = 1·46, 95% CI 1·03–2·07). The build-up of Anopheles culicifaciespopulations before the start of the transmission season had taken place in a stream near the village. Living close to the stream was a risk factor for malaria early in the transmission season, although this did not reach statistical significance (comparing <250 m with >500 m, RR = 2·13, 95% CI 0·96–4·71).

In this paper a formal framework is proposed in which variousinformative actions are combined, corresponding to the different ways in whichrational agents can acquire information. In order to solve the variousconflicts that could possibly occur when acquiring information fromdifferent sources, we propose a classification of the informationthat an agent possesses according to credibility. Based on this classification, we formalize what itmeans for agents to have seen or heard something, or to believesomething by default. We present a formalization of observations,communication actions, and the attempted jumps to conclusions thatconstitutes default reasoning. To implement these informative actionswe use a general belief revision action which satisfies theAGM postulates; dependent on the credibility of the incominginformation this revision action acts on one or more parts ofthe classified belief sets of the agents. The abilities of agents formalizeboth the limited capacities of agents to acquire information, and the preference of one kind of information acquisition to another. A very important feature of our approach is that it shows how to integratevarious aspects of agency, in particular the (informational) attitudesof dealing with information from observation, communication and defaultreasoning into one coherent framework, both model-theoretically andsyntactically.

Larvae of the caddisTrichostegia minor (Curtis) were collected from four woodland pools in The Netherlands, three of which are temporary, from August 1986 till June 1987. Eggs and larvae of this species proved to be very well adapted to drought, freezing, strongly fluctuating pH and alkalinity levels and prolonged oxygen deficit. The life cycle ofT.minor in a small woodland marsh overgrown byCalla palustris took one year. Adult flight period started at the end of May. Oviposition took place independent of water. Hatching of the eggs started in September and was probably induced by immersion. During the larval stage from September until May, 5 instars could be distinguished by the size of the head capsule. Growth of instars I, II and III during autumn was moderate. Most larvae overwintered as instar III or IV. Possibly there was a larval diapause during winter. In spring rapid growth to instar V took place prior to pupation. Growth rate, expressed as the increase of mean individual dry weight was highest from March to April (2.05±0.75% DW.m−2.d−1). In extremely shallow water growth in spring was initially more rapid compared to growth in deeper water. During winter the growth rate decreased to 0.038±0.071% DW.m−2.d−1. Net annual production based on the changes of momentary biomass was 183.2±31.7 mg DW.m−2.y−1 or 177.2±31.3 mg AFDW.m−2.y−1. Production loss during the winter season was 75.1±10.8 mg DW.m−2.y−1 or 72.3±10.6 mg AFDW.m−2.y−1.

We show how defaults can be used for counterfactual reasoning. We use a framework of modal logic to reason about both defaults and counterfactuals, in which one can express certainties, possibilities, actualities and (preferred or practical) beliefs in a distinct manner. Firstly, we discuss some properties of our approach in relation to other approaches in the literature.

In this paper we indicate how default logic can be based on epistemic logic, and particularly how we may employ Halpern & Moses' minimal epistemic states for this purpose. In this way we obtain a simple and natural S5-based logic for default reasoning that appears to be cumulative in the sense of Kraus, Lehmann and Magidor.

Abstract: An ecological classification of surface waters in the Netherlands is presented. This classification is based on literature data and the authors opinions concerning the habitat range of macroinvertebrate taxa. Water types were defined by key factors. Taxa were assigned to these water types and provided with a characterizing weight. The list may be a useful tool in the ecological management of waters.

The 2009 influenza A (H1N1) pandemic prompted the World Health Organization (WHO) to recommend countries to establish a national severe acute respiratory infections (SARI) surveillance system for preparedness and emergency response. However, setting up or maintaining a robust SARI surveillance system has been challenging. Similar to other countries, surveillance data on hospitalisations for SARI in the Netherlands are still limited, in contrast to the robust surveillance data in primary care.