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PostprintThis is the accepted version of a paper published in Journal of personal and ubiquitous computing. This paper has been peer-reviewed but does not include the final publisher proof-corrections or journal pagination. Citation for the original published paper (version of record):Ståhl, A., Höök, K., Svensson, M., Taylor, A., Combetti, M. (2009) Experiencing the Affective Diary. Journal of personal and ubiquitous computingAccess to the published version may require subscription. (0)1223 479999 {annas, kia, martins}@sics.se ast@microsoft.com Abstract: A diary is generally considered to be a book in which one keeps a regular record of events and experiences that have some personal significance. As such, it provides a useful means to privately express inner thoughts or to reflect on daily experiences, helping in either case to put them in perspective. Taking conventional diary keeping as our starting point, we have designed and built a digital diary, named Affective Diary, with which users can scribble their notes, but that also allows for bodily memorabilia to be recorded from body sensors and mobile media to be collected from users' mobile phones. A premise that underlies the presented work is one that views our bodily experiences as integral to how we come to interpret and thus make sense of the world.We present our investigations into this design space in three related lines of inquiry: (i) a theoretical grounding for affect and bodily experiences; (ii) a user-centred design process, arriving at the Affective Diary system; and (iii) an exploratory end-user study of the Affective Diary with 4 users during several weeks of use. Through these three inquiries, our overall aim has been to explore the potential of a system that interleaves the physical and cultural features of our embodied experiences and to further examine what media-specific qualities such a design might incorporate. Concerning the media-specific qualities, the key appears to be to find a suitable balance where a system does not dictate what should be interpreted and, at the same time, lends itself to enabling the user to participate in the interpretive act. In the exploratory end-user study users, for the most part, were able to identify with the body memorabilia and together with the mobile data, it enabled them to remember and reflect on their past. Two of our subjects went even further and found patterns in their own bodily reactions that caused them to learn something about themselves and even attempt to alter their own behaviours.

The mixing behavior of binary mixtures of the pure alkylglycosides:  β-decylglucoside (β-C10G), β-dodecylglucoside (β-C12G), β-decylmaltoside (β-C10M), and dodecylmaltoside (C12M) in combination with different common surfactants has been studied. First, the effect of the nonionic polar headgroup and chain length of the glycosidic surfactants in the mixed micellization with sodium dodecyl sulfate (SDS) was investigated. Further on, to analyze the effect of the ionic headgroup on the micellization of the glycosidic surfactant, β-C10G was mixed with different surfactants:  dodecyltrimethylammonium bromide (DTAB), dodecylheptaethylene glycol ether (C12E7), and β-C10M. All the mixed systems under study adapt reasonably well to the model developed by Rubingh, with negative values for the interaction parameter, βm, indicating a favorable interaction between the mixed surfactants. In the mixtures with SDS and the glycosides, the interactions become stronger when the hydrocarbon chain length of the surfactant is shorter and the hydrophilic headgroup is larger, i.e., when the surfactants become more hydrophilic. The β-C10G mixes favorably with the other surfactants, the interaction becoming stronger in the order C12E7, β-C10M, SDS, DTAB. The strong interaction in micellization with DTAB is explained by assuming an anionic character in the β-C10G molecule, as shown by electroosmosis measurements. Finally, the favorable interaction with β-C10M is explained by considering the packing between the headgroups of both nonionic surfactants.

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The term Social Navigation captures every-day behaviour used to find information, people, and places -namely through watching, following, and talking to people. We discuss how to design information spaces to allow for social navigation. We applied our ideas in a recipe recommendation system. In a follow-up user study, subjects state that social navigation adds value to the service: it provides for social affordance, and it helps turning a space into a social place. The study also reveals some unresolved design issues, such as the snowball effect where more and more users follow each other down the wrong path, and privacy issues.

Lipolase and Lipozyme are produced in large quantities (as a result of genetic engineering and overexpression) for the detergents market and provide a cheap source of highly active biocatalysts. Humicola lanuginosa lipase (HIL) and Rhizomucor miehei lipase (RmL) have been isolated in partially purified form from commercial preparations of Lipolase and Lipozyme, respectively. These lipases were solubilized in Aerosol-OT (AOT)-stabilized water-in-oil (w/o) microemulsions in n-heptane. HIL and RmL activity in these microemulsions was assayed by spectrophotometric measurement of the initial rate of p-nitophenyl butyrate hydrolysis, and by chromatographic determination of the initial rate of octyl decanoate synthesis from 1-octanol and decanoic acid. The hydrolytic activity of HIL in microemulsions measured as a function of buffer pH prior to dispersal, followed a sigmoidal profile with the highest activities observed at alkaline pHs. This broadly matches the pH-activity profile for tributyrin hydrolysis by Lipolase in an aqueous emulsion assay. The hydrolytic activity of RmL in the same microemulsions, measured as a function of pH, gave a bell-shaped profile with a maximum activity at pH 7.5. Again, the observed pH-activity profile was similar to that reported for a purified RmL in a tributyrin-based aqueous emulsion assay. In contrast, the esterification activity exhibited by both HIL and RmL in AOT microemulsions over the available range pH 6.1 to 10.4, decreases as the pH increases, most likely reflecting the effect of substrate ionization. The dependence of the hydrolytic and condensation activity of HIL on R, the mole ratio of water to surfactant, were similar with both profiles exhibiting a maximum at R = 5. The hydrolytic and esterification activities of RmL followed similar R-dependent profiles, but the profiles in this case exhibited a maximum at R = 10. The water activities at these R values were directly measured as 0.78 and 0.9, respectively. Measured water activities were unperturbed by the presence of lipase at the concentrations used in these studies.

The hydrotropic effect of different alkyl polyglucosides (APG) has been studied and compared with a model hydrotrope, toluol-4-sulfonic acid. The effect has been assessed by two different methods: (i) as the cloud point elevation of a solution containing different nonionic surfactants upon addition of the hydrotrope and (ii) the destabilization of liquid crystalline phases in a ternary system. The effect of the hydrophobic alkyl group length was found to be opposite in the two methods. APG with intermediate alkyl chain lengths (octyl and decyl) was shown to be very effective in elevating the cloud point, while APG with a short (butyl) group was the most efficient in destabilizing liquid crystalline phases in the system of water, sodium dodecyl sulfate and pentanol. Effects on phase behavior and cloud point elevation with addition of an APG are highly dependent on its structure. However, the correlation between structural effects as observed in the two methods requires further study. JSD 1, 485-489 (1998).