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Abstract: The Dutch dairy chain is aiming to achieve energy-neutral production by bringing the whole chain from dairy farm to factory ultimately to be self sufficient in energy in year 2020, through a combination of wind, solar and biogas. This paper investigated the economic feasibility of producing green gas from digestion of dairy manure and other co-substrates. A simulation model of producing 17 PJ of green gas from 2 business models, stand-alone and central upgrading was developed. Probability distributions were chosen to describe the profitability and risks for individual business models and for the aggregate energy production at dairy sector level. Data sources, among others, stem from 23 operating biogas plants in Netherlands. Simulation results showed that the probability of a negative net present value (NPV) is less than 50% for both individual models. The probability that the combined business models producing 17 PJ will result in a negative NPV is 23%. A total of 109 plants are needed to produce the total energy, requiring 8.5% of the total amount of cattle manure produced in the Netherlands to be processed. Sensitivity analysis based on spearman rank correlation coefficient between NPV and each of the sample input distributions showed that biogas yield and investment costs have significant effect in determining the NPV values. [Copyright &y& Elsevier]

Abstract: Nutritional conditions in early life may causally affect health at older ages. This paper examines the effects of early life exposure to the Dutch famine (Winter 1944–45) on the prevalence of heart diseases, peripheral arterial diseases (PAD) and diabetes mellitus (DM) at ages 60–76. Analyses are performed using data from the fifth cycle of the Longitudinal Aging Study Amsterdam. Exposure to the famine is determined by reported place of residence during the Dutch famine, with those living in the cities in the West of the Netherlands defined as exposed (n = 278) and those living in the rural areas in the West or living in the North or East defined as non-exposed (n = 521). We successively compare the prevalence of heart diseases, PAD and DM at ages 60–76 of 370 males and 429 females exposed and non-exposed to the famine in early life. We distinguish four age classes of exposure in early life: gestation and infancy (ages 0–1), childhood (age 1–5), pre-adolescence (ages 6–10) and adolescence (ages 11–14). The analysis shows that exposure to severe undernutrition at ages 11–14 is significantly associated with a higher probability of developing DM and/or PAD at ages 60–76. The associations are found only in women, but not in men. If suggests that adolescence may be a critical period with respect to exposure to adverse (nutritional) conditions and that research should take this into account. These findings are relevant for children in developing countries who are exposed to severe nutritional deprivation. [Copyright &y& Elsevier]

Abstract: Purpose: Routine physical examination is recommended in follow up guidelines for women with a history of breast cancer. The objective of this paper is to assess the contribution of routine physical examination in addition to mammography in the early diagnosis of breast cancer recurrences. Patients and methods: The medical follow-up documents of 669 patients were reviewed. 127 contra-lateral breast cancers (CBCs) and 58 loco-regional recurrences (LRRs) in 163 patients were included. The additional contribution of routine physical examination over mammography was evaluated with the proportions of CBCs or LRRs detected by physical examination alone. χ 2 tests were used to compare the difference of contribution of physical examination among subgroups. Results: Seven (6%) out of 127 CBCs and 13 (22%) out of 58 LRRs were detected by routine physical examination alone. Six LRRs (17%; 6/35) were in patients after breast conserving surgery and seven LRRs (30%; 7/23) in patients after mastectomy. There was a trend that the contribution of physical examination is higher in women under 60years of age in the detection of CBCs (9%; 5/57) and LRRs (28%, 8/29) than in women over 60years of age (CBCs:3%; 2/70 and LRRs:17%, 5/29; χ 2 =3.090, P =0.079). Conclusions: Twenty-two percent of loco regional breast cancer recurrences would have been detected later without physical examination. Routine physical examination may be most valuable for women with a history of breast cancer younger than 60years at follow-up visit. [Copyright &y& Elsevier]

Abstract: In the Netherlands, the design of dikes and other water retaining structures is based on an acceptable probability (frequency) of overtopping. In 1993 a new safety concept was introduced based on total flood risk. Risk was defined as the product of probability and consequences. In recent years advanced tools have become available to calculate the actual flood risk of a polder. This paper describes the application of these tools to an existing lowland river area. The complete chain of calculations necessary to estimate the risk of flooding of a polder (or dike ring) is presented. The difficulties in applying the present day tools and the largest uncertainties in the calculations are shown. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to propose a method for the evaluation of tunnel safety using probabilistic risk assessment. The framework includes three criteria; personal-, societal- and economic risk. The use of personal and societal risk is becoming more and more widespread. There are however, still some difficulties in using the economic risk criterion. As a first step towards economic risk optimisation, the cost effectiveness of addition and removal of safety measures in tunnels is investigated. Finally, the application of the three proposed criteria is further discussed for some tunnelling projects currently underway in the Netherlands. [Copyright &y& Elsevier]