To study the dispersal of dengue vector mosquitoes in Singapore, females of Aedes aegypti (L.) and Aedes albopictus (Skuse) (Diptera: Culicidae) were fed blood containing rubidium (Rb), which was detectable in their eggs by means of Graphite Furnace Atomic Absorption Spectrophotometry (GFAAS). Laboratory calibration of the Rb reading, for a range of egg numbers from Rb-fed females, indicated a reasonably linear relationship and an unequivocal distinction between results with zero and one marked egg. Rb-marked female Aedes mosquitoes aged 3-5 days were released in semi-rural and urbanized parts of Singapore, with an array of ovitraps extending to a radius of 320 m from the release point. Subsequently, Rb-marked Aedes eggs were detected throughout the array, with similar distributions on each of the 4 days after release. More Rb was detected nearer the release point. However, when correction was made for the greater areas of zones further from the release point (and therefore presumably existence of more alternative oviposition sites), there were no significant differences in the numbers of marked eggs per ovitrap in the zones nearer or further from the release points. It is concluded that females of both these Aedes (Stegomyia) species could disperse easily and quickly throughout areas of radius 320 m in search of oviposition sites. This contrasts with the general belief that Ae. aegypti seldom flies more than 50 m and that control operations can safely be based on such an assumption. Releases on level 12 of a 21-storey apartment block, with ovitraps on each storey, showed similar easy and rapid dispersal to the top and bottom of the block.

Although Singapore has an intensive dengue control program, dengue remains endemic with regular outbreaks. We report development and use of a novel adult oviposition trap, the Gravitrap, in managing dengue cluster areas. The Gravitrap is a simple, hay infusion-filled cylindrical trap with a sticky inner surface to serve as an oviposition site for gravid female Aedes mosquitoes. Wire gauze fitted above the water level minimizes the risk of it being an unwanted breeding habitat. The Gravitrap was deployed in 11 dengue cluster areas throughout Singapore. Aedes aegypti was the predominant mosquito caught in the trap and some (5.73%) were found to be positive for dengue virus.

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The growth and diversity of electronic journals (e-journals) in the past five years had led many to predict the extinction of print journals and that a new paradigm is sweeping scholarship. Some others however, believe that future electronic scholarly journals will be different from their print antecedents and that both will fill a different niche, and will be necessary for the growth of knowledge. This paper considers the future of e-journals in the light of the use and perception of graduate student end-users, and their expectations of future e-journals. A segment of the results from a recent user study that present significant implications for the design of future e-journals are reported. The results show a significantly high acceptance of e-journals by this category of users. Generally, e-journals are expected to be different from print journals, with novel forms of functionality not possible in their print counterparts.

Purpose -This study seeks to examine, from the viewpoint of 12 adult fiction readers who are members of book clubs, how they go about selecting fiction books to borrow from the public library. Design/methodology/approach -Each participant took part in an individual, semi-structured, face-to-face interview. Using Williamson's Ecological Model of Information Seeking and Use as the conceptual framework, the study examined the role that fiction readers' "internal environments" and "external contexts" played in their book choices. Findings -The selection of fiction books at the public library occurred, to a large extent, outside it. Fiction books were selected as part of everyday life information seeking, influenced by study participants' personal characteristics and circumstances as well as sources from their everyday lives, which typically included family, friends, book club and the mass media. While the public library was the main means by which study participants obtained their fiction books, it was not the first source to which they turned for ideas on what to read. Originality/value -The study moves from a preoccupation of readers' actions at the public library to examine, more holistically, how everyday life information sources influence their choices of fiction books at the public library. It highlights the purposive and serendipitous dimensions of book selections and also underscores the importance of recognizing trust as a determining factor in book selection.