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Brominated flame-retardants (BFRs), including polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD), were analysed in 77 eggs of 13 wild bird species from Gauteng and northern Free State (the industrial heartland of South Africa). BFRs were in all eggs, but not all BFRs were quantifiable. Concentrations ranged between 2.9 and 46 ng g−1wm (wet mass) and the predominant congeners were BDE-47, -153, -154, -183 and -209. The BFR compositional patterns of the congeners in eggs differed between species, feeding guilds, and habitats. Differences in associations of birds with humans seemed to have as much an influence as the trophic levels occupied by the maternal animals. The congener pattern of BFRs differed between terrestrial and aquatic species. The congener concentrations and patterns also differed from eggs from other countries, suggesting differences in sources. BFR concentrations in eggs from the current study area were below a reported no observed effect level (NOEL; 1 000 ng g−1wm). Although this suggests that the BFRs do not pose a risk, the NOEL was mostly based on information from birds from moderate and colder climates. This NOEL might not apply to birds from warmer climates with different life histories, as in the current study, because there are currently only draft regulations on importing BFRs or BFR-containing products in South Africa. The BFR-containing products otherwise destined for countries with BFR restrictions in place may now find their way to South Africa. The additional waste these poorly regulated products generate will eventually find their way to landfills ensuring that release to the environment and consequent exposures to biota will continue without effective interventions and waste management. Our findings indicate the need for on-going environmental monitoring to assess trends, identify hot spots, investigate effects, strengthen waste management, and the need to urgently implement the commitments under the Stockholm Convention.

One of the key characteristics of the ICT industry is convergence, which has to do with bringing together system technologies and actors from different industries. Components provided by various actors are integrated to create end-user services. The design of these service systems requires the collaboration of these actors in what are known as value webs or eco-systems. Attention has to be paid to the interrelatedness and co-evolution of the technological systems and the organisational domains. In this paper, two cases are presented to illustrate the interrelatedness of design-related choices in the systems and actor domain, showing the need to take both the technological systems design perspective and the actor design perspective into account. Furthermore, the need for a multi-theory and multi-method approach is illustrated. Next, the focus is on one of the core design challenges of ICT service systems, i.e., integrating systems components which are dealt with by using a layered design approach.

This paper focuses on future developments in society in general, and in the insurance industry in particular, and the development of business models that can be used to reinforce the position of intermediaries in the insurance value chain in a time when they face uncertain technical, marketing and regulatory developments. This paper attempts to integrate trend and scenario analysis with business model design, in an industry sector where innovation is slowly taking off. By combining trend analysis and an 'outside-in' scenario methodology and business model design, we design strategic options and new alternative business models. On the basis of trend analysis we defined two major axes for the scenario analysis: the level of regulation and the adoption and use of Information and Communication Technology (ICT). Based on these axes we developed four scenarios. We assessed the impact of relevant developments outside for each scenario. General developments are leaner government, and increasing use of new ICT-applications, while developments within the industry include channel competition and the implementation of the (Dutch counterpart of the) Financial Services Act. We have analysed the demands on management resulting from these developments, derived strategic options and designed illustrative business models.

The feeding requirements of earthworms have not been fully established. A vermiculite matrix was used to determine the dietary effects of various organic substances. Vitamins, DNA, and humic acid as additives improved growth and allowed reproduction of Eisenia fetida in a cellulose-based medium. Mature worms were not able to adapt to the medium and 20-day-old worms were used. Rates of growth and cocoon production were slightly less in a defined medium (7% organic content) than in a cow-manure control medium (70% organic content). The medium is likely to prove useful as a reference medium for obtaining biological information.

Concentrations of p,p'-DDT, p,p'-DDE, and p,p'-DDD were determined in serum of members of households of two different areas of KwaZulu. Annual intradomiciliary application of DDT is used for the interruption of malaria transmission in one area (the exposed group) while the other served as the control.Demographic differences between the two groups resulted in significantly more females in the control group. The two groups were comparable with respect to age. Serum from household members living in DDT-treated dwellings had significantly higher (p < .005) levels of SDDT and metabolites (mean SDDT 140.9 μg/l) than those from the control area (mean SDDT 6.04 μg/l). Percentage DDT was also significantly higher (p < .05) in the exposed group (28.9%) than the control group (8.3%). SDDT for the 3-10 yr age interval (168.6 μg/l) was significantly higher (p < .05) than the 20-29 (60.5 μg/l) and 30-39 (84.2 μg/l) yr age intervals. There seemed to be two groups with regard to accumulation and elimination. The age group 3-29 appeared to be eliminating DDT, most likely accumulated from contaminated breast milk, faster than they accumulated it. From around 29 yr of age accumulation predominated as the levels increased with age. Regression analysis suggested pharmacokinetic differences for DDE and DDT between the two groups.Liver function parameters between the two groups only differed significantly for gamma-glutamyl transferase (γGT) (p < .005), but the influence of difference in alcohol consumption, which was significantly higher in the exposed group (p < .0001), offered a better explanation. Those of the exposed group that consumed alcohol had a significantly higher (p < .05) mean γGT level (41.5 IU/I) than those that did not (20.2 IU/I), but were not significantly different for SDDT (p > .05). The safety of DDT used in malaria control for subjects aged 3 and older was confirmed by the levels of DDT in serum when compared with other studies, which showed lack of any negative effects associated with these levels in adults, and an apparently normal liver function in the exposed and control groups.

Selective breeding of invertebrates has been suggested by many but studied by few. The possibilities of improving characters like biomass, maturation time, coccoon production rate, and hatching success of cocoons for the earthworm Eisenia fetida were examined in the present study. The results showed that biomass, maturation time, and number of hatchlings could be successfully improved by selective breeding, although a concomitant tendency to a lower reproductive rate, as found in vertebrates, was observed. Other characters like cocoon production rate, hatching success, and number of hatchlings per cocoon also showed promising results.

Concentrations of p,p'-DDT, p,p'-DDE, and p,p'-DDD have been determined in breast milk of mothers residing in two different areas of KwaZulu. Annual intradomiciliary application of DDT was used for the interruption of malaria transmission in one area, while the other served as the control. Milk from mothers living in DDT-treated dwellings had significantly higher mean levels of DDT and metabolites (mean SDDT 15.83 mg kg-1 in milk fat) than those from the control area (0.69 mg kg-1). The highest recorded SDDT value was 59.3 mg kg-1 (milk fat). Primiparous mothers from the malarious area had significantly more SDDT and metabolites (SDDT 24.82 mg kg-1) than multiparous mothers from the same area (mean 12.21 mg kg-1). Parity was the best predictor of DDT in breast milk of the exposed group.The percentage DDT and the SDDT increased significantly with an increase in parity. The same, but not significant, trend was also found for the control group. It was hypothesized that the increase in percentage DDT that occurred with higher parities was due to the uptake of DDT and elimination via milk. This process was faster than the uptake and endogenous formation of DDE.Designing predictive models using multiple regression was not very successful. The recorded levels do not represent an appreciable health risk to the mothers. From the literature it was deduced that at the recorded levels, a well-founded risk to the infants, particularly the firstborns, exists in sprayed areas.

Abstract:  The aim of this experiment was to investigate whether Eisenia fetida hatchlings of different ages, kept initially without food, could be used to obtain worms of a comparable development stage (measured as growth) with similar maturation properties (measured as clitellum development). Seven groups of hatchlings, each differing in age by 7 days (range: 0–42 days) were collected as follows. Cocoons were kept in water in multicell containers and individuals that hatched during a 24-h period were placed on moist vermiculite with no food, at weekly intervals. The longest period that hatchlings were fasted was 42 days, after which food was added and growth monitored for 50 days. No differences in weight gain between the different batches were observed. Analysis of the growth curves and attainment of sexual maturity (clitellum development) indicated no effect of age or stage of development at the onset of feeding. It was concluded that this technique allows the production of cohorts of E. fetida, synchronised with respect to development stage, for use in toxicological and biological investigations that require control of factors such as development stage, age and size, and in particular for use in toxicological experiments complying with OECD regulatory procedures.

Zusammenfassung Einige Heliumbogenlinien (2S-3P, 2P-4D, 2p-4s, 2P-5P komb.) und eine He+-Ionlinie (Paschenserie) sind in kondensierter Entladung bei verschiedenen Stromdichten untersucht werden. Es stellte sich heraus, daß die Bogenlinien alle in gleicher Weise verlaufen und die Funkenlinien viel stärker ansteigen als die Bogenlinien. Letztere haben überdies ein Minimum der Intensität als Funktion der Spannung.

Using an instrument described in the preceeding article, the calibration of a proving ring has been carried out. The results show that this method of calibration has advantages over the classical procedure of direct loading at fixed intervals.