Finite curved creases in infinite isometric sheets

Geometric stress focusing, e.g. in a crumpled sheet, creates point-like vertices that terminate in a characteristic local crescent shape. The observed scaling of the size of this crescent is an open question in the stress focusing of elastic thin sheets. According to experiments and simulations, this size depends on the outer dimension of the sheet, but intuition and rudimentary energy balance indicate it should only depend on the sheet thickness. We address this discrepancy by modeling the observed crescent with a more geometric approach, where we treat the crescent as a curved crease in an isometric sheet. Although curved creases have already been studied extensively, the crescent in a crumpled sheet has its own unique features: the material crescent terminates within the material, and the material extent is indefinitely larger than the extent of the crescent. These features together with the general constraints of isometry lead to constraints linking the surface profile to the crease-line geometry. We construct several examples obeying these constraints, showing finite curved creases are fully realizable. This approach has some particular advantages over previous analyses, as we are able to describe the entire material without having to exclude the region around the sharp crescent. Finally, we deduce testable relations between the crease and the surrounding sheet, and discuss some of the implications of our approach with regards to the scaling of the crescent size.Comment: 15 pages, 7 figure

Usage Tests of Oak Moss Absolutes Containing High and Low Levels of Atranol and Chloroatranol.

Atranol and chloroatranol are strong contact allergens in oak moss absolute, a lichen extract used in perfumery. Fifteen subjects with contact allergy to oak moss absolute underwent a repeated open application test (ROAT) using solutions of an untreated oak moss absolute (sample A) and an oak moss absolute with reduced content of atranol and chloroatranol (sample B). All subjects were in addition patch-tested with serial dilutions of samples A and B. Statistically significantly more subjects reacted to sample A than to sample B in the patch tests. No corresponding difference was observed in the ROAT, though there was a significant difference in the time required to elicit a positive reaction. Still, the ROAT indicates that the use of a cosmetic product containing oak moss absolute with reduced levels of atranol and chloroatranol is capable of eliciting an allergic reaction in previously sensitised individuals

En studie kring den Interna kommunikationen i Arla Foods Svenska Division

Aim: My aim with this study is to investigate whether the co-workers in the company Arla Foods is satisfied with the communication between the company and the employees. If there are any changes to be made or if it works well as it is now. Method: I have sent out invistigationforms to 85 co-workers within Arla Foods. This forms included questions about Arla Foods internal communication and how the co-workers apprehend this. I have also made 7 interviews over the phone with co-workers on the dairys around Sweden. Including in these 7 interviews have I also talked and posed questions to representatives for the trades-union within Arla Foods. I have treated all the answers that have come back to me and from them have I made conclusions how the co-workes apprehend the companys communication. Main Results: The main results I have been able to see is that the way the co-workers prefer to have their communication is trough the intranet, the staffpaper and the information verbally from the nearest chief. The co-workers are not so interested in the market and what’s hapening within Arla Foods in Denmark. They think that on the Intranet should it be easier to find news and other things you would like to read about