While we know that upcoding of diagnosis-related groups (DRGs) regularly occurs, we have little knowledge of the role of the technical features of coding systems in inducing coding behaviour. This paper presents methods for investigating the financial structure of the Dutch DRG system, and more in particular the grouper software, to gain such insight. The paper describes a system for investigating the robustness of the reward structure, by simulating the response of the DRG system to small changes in individual coding. The results from these analyses are used to visualise some data on coding behaviour, and to investigate how this behaviour is affected by incentives in the technical features of the DRG system. A number of technical weaknesses in the system are also identified.

Islands offer unique model systems for studying fisheries development in relation to the growing global seafood trade. This study examines how export-driven fisheries in India's oceanic islands (Andaman and Nicobar Islands and Lakshadweep Islands) differ significantly as a result of their varied history, culture, available infrastructure and market access. Despite being geographically closer to export centres on the Indian mainland, processing and transport infrastructure in the Lakshadweep Islands are limited. This only allows for the trade of non-perishable commodities like dried tuna that are caught using traditional pole-and-line fishing techniques, restricting reef exploitation to local preference-based consumption and opportunistic export. The Andaman Islands, on the other hand, with multiple daily flight connections and large private and government processing facilities, are better connected to export markets. The relatively recent and multicultural fisheries of these islands supply marine commodity chains for reef fishery goods such as dried shark fins, frozen snapper fillets and chilled groupers. The Nicobar Islands are furthest away from mainland export centres and are mostly populated by indigenous communities – fishing here is mostly for subsistence and local sale. Revised estimates of travel times to export market centres are counterintuitive in terms of geographical distances and are significantly different from travel times to local markets.

Corals of the Hawaiian Archipelago are well situated in the North Pacific Gyre (NPG) to record how bomb-produced radiocarbon has been sequestered and transported by the sea. While this signal can be traced accurately through time in reef-building corals and used to infer oceanographic processes and determine the ages of marine organisms, a comprehensive and validated record has been lacking for the Hawaiian Archipelago. In this study, a coral core from Kure Atoll in the northwestern Hawaiian Islands was used to create a high-resolution bomb 14C record for the years 1939–2002, and was then used with other 14C measurements in fish otoliths and seawater to explore differences and similarities in the bomb 14C signal throughout the Hawaiian Archipelago. The Kure Atoll sample series produced a well-defined bomb 14C curve that, with some exceptions, was similar to other coral 14C records from the Hawaiian Archipelago. Subtle differences in the coral 14C records across the region may be explained by the large-scale ocean circulation patterns and decadal cycles of the NPG. The most rapid increase of 14C, in the 1950s and 1960s, showed similar timing across the Hawaiian Archipelago and provides a robust basis for use of bomb 14C dating to obtain high-precision age determinations of marine organisms. Reference otoliths of juvenile fish demonstrated the use of the post-peak 14C decline period as a viable reference in the age validation of younger and more recently collected fishes, and effectively extended the utility of bomb 14C dating to the latest 30 yr.

Members of the Epinephelinae subfamily of serranids (‘grouper’) are heavily exploited by bottom longline in the Gulf of Gabès located in the south of Tunisia. In addition to direct mortality, hook and release mortalities likely occur when fish are caught and released, due to injuries sustained from hooking as well as those associated with retrieval. During five experimental trips (29 fishing sets) conducted in August 2011 from the port of Djerba (south of the Gulf of Gabès), we evaluated the effect of hook styles (9/0 ‘J’ and 12/0 circle hook) on groupers and non-target species. A total of 340 specimens representing 10 species were captured. The higher catch rate was registered for Epinephelus aeneus. The majority of groupers captured were female mature. The circle hook increased the capture of the most common grouper E. aeneus and did not affect the catch of Epinephelus marginatus and Epinepheleus costae. The effect of the type of hook on hooking location was inconclusive. Managing of the grouper fishery using some management actions such as size limits, bag limits, and closed seasons may prevent more unnecessary losses of grouper species. From this preliminary study, a definite conclusion for or against the use of circle hook cannot be drawn. Further research on the role of gear modification and hook designs in reducing by-catch, hooking-related injury and mortality should be encouraged.

We used timed underwater visual censuses to study grouper relative abundance and diversity on the west coast of India. Eighteen grouper species were observed in these surveys, including two new records for the west coast of India, Aethaloperca rogaa and Plectropomus areolatus. Cephalopholis formosa and Epinephelus faveatus were the most abundant species observed with the latter more numerous on inshore than offshore rocky reefs. Ecological and distributional notes are given for the species observed.

In order to study the impact of fishing on a grouper population, we propose in this paperto model the dynamics of a grouper population in a fishing territory by using structuredmodels. For that purpose, we have integrated the natural population growth, the fishing,the competition for shelter and the dispersion. The dispersion was considered as aconsequence of the competition. First we prove, that the grouper stocks may be lesssensitive to the removal of large male individuals if female population are totallyprotected. Second, we show that fishing does not disturb the demographic structure of thepopulation. Finally, we prove that female selective fisheries have the potential ofdrastically reduce reproductive rates. We also prove that male fishing decreasescompetition and then increases the total population number.