Swiping paper: the second hand, mundane artifacts, gesture and collaboration

It is widely recognised that paper remains a pervasive resource for collaboration and yet there has been uncertain progress in developing technologies that aim to enhance paper documents with computational capabilities. In this article, we discuss the design of a technology that interweaves developments in hardware and materials, electronics and software, and seeks to create new affinities between digital content and paper. The design of the technology drew from findings from naturalistic studies of the uses of paper, particularly when considering how ‘users’ might ‘interact’ with the augmented technology. We briefly review these studies and discuss the results of an evaluation of the emerging technology. Analysis of the fine details of the conduct of participants in these assessments suggest how, even when we design simple forms of interaction with a device, these can be shaped and transformed by the participation and collaboration of others.     

Photoactivation of an inhibitor of the 12/15-lipoxygenase pathway

Lipoxygenases are lipid-peroxidizing enzymes that have been implicated in the pathogenesis of inflammatory diseases and lipoxygenase inhibitors may be developed as anti-inflammatory drugs. Structure comparison with known lipoxygenase inhibitors has suggested that (2Z)-2-(3-benzylidene)-3-oxo-2,3-dihydrobenzo[b]thiophene-7-carboxylic acid methyl ester might inhibit the lipoxygenase pathway but we found that it exhibited only a low inhibitory potency for the pure 12/15-lipoxygenase (IC(50) = 0.7 mM). However, photoactivation, which induces a Z-to-E isomerization of the double bond, strongly augmented the inhibitory potency and an IC(50) value of 0.021 mM was determined for the pure E isomer. Similar isomer-specific differences were observed with the recombinant enzyme and its 12-lipoxygenating Ile418Ala mutant, as well as in intracellular lipoxygenase activity. Structure modeling of the enzyme/inhibitor complex suggested the molecular reasons for this isomer specificity. Since light-induced isomerization may proceed in the skin, such photoreactive compounds might be developed as potential drugs for inflammatory skin diseases.     

Reasons for the Discoloration of Postconsumer Poly(ethylene terephthalate) during Reprocessing

Gray and/or yellow discoloration may occur during repeated heating of poly(ethylene terephthalate) (PET). Both phenomena can cause problems in further application. In this work, the reasons for the discoloration of PET during reprocessing are investigated by physical and chemical analysis such as colorimetry, size exclusion chromatography, viscosimetry (η_inh.), inductively coupled plasma mass spectrometry, X‐ray photoelectron spectroscopy, and MALDI‐ToF‐MS analysis. It is found that the antimony content which originates from catalyst residues used in PET synthesis has high influence on the gray discoloration obtained during reprocessing of PET. Antimony ions are reduced to elementary antimony during heating to temperatures above 230 °C as proven by X‐ray photoelectron spectroscopy. The yellow discoloration is partially generated by polyamide contaminants which are used as barrier layers in PET packaging materials such as soft drink bottles. In conclusion, to prevent discoloration of postconsumer PET during reprocessing different methods such as oxidation of gray metallic antimony or sorting out of polyamide contaminants are needed.

     

Aggregate Structures: Material and Machine Computation of Designed Granular Substances

In inanimate nature, large masses of granular substances are in constant processes of formation through perpetual cycles of erosion and accretion. What if architecture was to emulate this behaviour and allow for its own continuous reconfiguration? Karola Dierichs and Achim Menges establish the notion of an ‘aggregate architecture’. Composed of large numbers of unbound yet designed granules, aggregates are based on a fundamentally different logic of construction. In contrast to assembly systems, aggregates materially compute their overall constructional configuration and shape as spatiotemporal behavioural patterns, with an equal ability for both: the stable character of a solid material and the rapid reconfigurability of a fluid. Copyright © 2012 John Wiley & Sons, Ltd.     

A comparison of spherical and cylindrical microparticles composed of nanoparticles for pulmonary application

Nano-embedded microparticles represent promising carrier systems to tackle the challenges of nanoparticle delivery into the lungs by inhalation. While spray drying is widely used for the incorporation of nanoparticles into microparticles, the template-assisted technique is a novel method to prepare aspherical, cylindrical microparticles composed of nanoparticles. In this work, both techniques were applied to produce both spherical and cylindrical nano-embedded microparticles. For both geometries particles consisting of gelatin nanoparticles, mannitol and leucine were prepared in three different sizes each. Cylindrical microparticles could be prepared with defined dimensions and narrow size distributions, allowing to target a wide range of aerodynamic diameters. The size of spherical microparticles was influenced by the spraying feed concentration, yielding only small differences in geometric and aerodynamic diameters and broad particle size distributions. Regarding the redispersibility of the nano-embedded microparticles, spherical particles showed better disintegration behavior and higher nanoparticle release in comparison to cylindrical particles upon contact with water. The template-assisted technique yielded higher nanoparticle content in contrast to spray drying. In summary, cylindrical particles represent a promising drug delivery system with high potential for later application. However, further improvements in the preparation method are required to enable higher yields and a possible later scale-up.

Copyright © 2018 American Association for Aerosol Research     

Preparation and Application of Iron‐substituted (Z)‐Enals: Synthesis of 5‐Substituted α,β‐Butenolides

A reaction sequence furnishing cyclic β‐[η⁵‐C₅H₅(CO)₂Fe]‐substituted enals 5 starting from β‐keto esters 1 is described. Organolithiums were found to react smoothly with the iron‐substituted enals yielding α,β‐butenolides 6 by an intramolecular cyclocarbonylation of the lithiumalkoxide initially formed. The influence of e.g. the reaction temperature and the solvent on the reaction cascade is discussed. A reaction mechanism is proposed.     

Granular Construction: Designed Particles for Macro-Scale Architectural Structures

Designing the individual particles of granular materials defines novel material characteristics of the overall granular system. This opens up a range of possibilities for architectural applications that are fully reconfigurable as the particles are not bound to each other. Karola Dierichs and Achim Menges of the Institute for Computational Design (ICD) at the University of Stuttgart provide an overview of recent research conducted at the Institute in this field. Autonomous construction is integrated into these systems through using either extrinsic autonomous machines or intrinsic autonomous particles.