A dual gradient assay for the parametric analysis of cell-surface interactions

Cellular response to microgrooves is addressed using a new assay format, comprising orthogonal gradients of continuously varied groove pitch and depth. Dual layer etch masks are created using a combination of micropatterning and plasma polymer deposition. A silicon substrate with a constant groove width of 8 μm and with ridge width increasing from 8 μm in 0.5 μm steps across 10 mm is fabricated by photolithography. A plasma-polymerized hexane film which is 120 nm thick at one end of these grooves, and 10 nm at the other, is deposited under a diffusion mask. Reactive etching of the patterned sample transfers a gradient of groove pitch and groove depth into the silicon substrate. A silicon master with a gradient of groove depth spanning more than two orders of magnitude (less than 10 nm to over 1000 nm) is used to create an injection molding inlay for mass replication of the screening topography. Polycarbonate replicas are molded for use in cell culture studies, and the functionality of the topography as a high-throughput screening platform is investigated. The response of MDCK, h-TERT fibroblasts, and LE2 endothelial cells is examined, in terms of attachment and morphological response to the variation in topographical cues, with the aim of pinpointing the optimal combination of groove pitch and depth to elicit a tailored response from each cell type. When the range of topographical features screened on a single substrate is considered, this new assay represents a significant step forward in the parametric design and analysis of topographical cues at the biomaterial interface.     

Are News Audiences Increasingly Fragmented? A Cross-National Comparative Analysis of Cross-Platform News Audience Fragmentation and Duplication

The move to high-choice media environments has sparked fears over audience fragmentation. We analyze news audiences across media platforms (print, television, and online) in 6 countries, going beyond platform-specific, single-country studies. We find surprisingly high levels of news audience duplication, but also that cross-platform audiences vary from country to country, with fragmentation higher in Denmark and the United Kingdom than in Spain and the United States. We find no support for the idea that online audiences are more fragmented than offline audiences, countering fears associated with audience segmentation and filter bubbles. Because all communication exists in the context of its audience, our analysis has implications across the field, underlining the importance of research into how trends play out in different contexts.     

Energy simulation for a high-rise building using IDA ICE: Investigations in different climates

In this paper a model of a high-rise building is constructed in the simulation program IDA ICE. The model is based on an IFC-model of a demonstration building constructed in Ljubljana, Slovenia, as part of an EU-project, EE-high-rise. The model’s energy performance was simulated for four cities: Umeå (Scandinavia), Ljubljana (Central Europe), Sibenik (Mediterranean) and Dubai (The Persian Gulf). Furthermore, the climate envelope of the building was modified with the aim to improve the model’s energy performance in each of the regions. The results were evaluated according to the energy requirements of passive house standard by the German Passive House Institute. The analysis suggests that the reference building model, which itself incorporates several energy efficient components, was unable to meet the German passive house standard in none of the four cities (Umeå, Ljubljana, Sibenik and Dubai) studied. By providing a combination of energy saving measures, such as modifications of thermal resistance of building envelope, the building may be able to meet the passive house standard in Ljubljana. The analysis concludes that the reduction in window area results in reduction of both heating and cooling demand. Increase in the thickness of the insulation and the thermal resistance of windows reduces the space heating demand for Umeå, Ljubljana and Sibenik (not applied for Dubai) while increasing the cooling demand for these cities. Increased airtightness has marginal effect on heating and cooling demand for all investigated cities. Reduced thermal resistance of windows will decrease cooling demand for Ljubljana, Sibenik and Dubai (not applied for Umeå). Reduced insulation thickness (not applied for Umeå) will decrease cooling demand for Ljubljana and Sibenik but not for Dubai. Reducing the insulation thickness may often result in reduced cooling demand for moderately warm countries since the average outdoor temperature could be lower than the indoor temperature during part of the cooling season. In those situations a reduced insulation thickness can cause heat flow from the relatively hot inside to the colder outside. However, for hot climates like in Dubai where outdoor temperature is higher than the indoor temperature for most of the year, reducing the insulation thickness will increase the cooling demand. This result suggests that the insulation thickness must be chosen and optimized based on heating and cooling demand, internal heat gain, and outdoor climate     

Monitoring organic loading to swimming pools by fluorescence excitation-emission matrix with parallel factor analysis (PARAFAC)

Fluorescence Excitation-Emission Matrix spectroscopy combined with parallel factor analysis was employed to monitor water quality and organic contamination in swimming pools. The fluorescence signal of the swimming pool organic matter was low but increased slightly through the day. The analysis revealed that the organic matter fluorescence was characterised by five different components, one of which was unique to swimming pool organic matter and one which was specific to organic contamination. The latter component had emission peaks at 420 nm and was found to be a sensitive indicator of organic loading in swimming pool water. The fluorescence at 420 nm gradually increased during opening hours and represented material accumulating through the day.     

Regional differences in world human body dimensions: the multi-way analysis approach

In the global market, it is vital to design products and work environments to satisfactorily meet the regional variations of human body dimensions. Few studies to date have, however, attempted to examine regional differences due to unavailability of data. Jürgens, H.W., Aune, I.A. and Peiper, U., 1990, International Data on Anthropometry, Occupational Safety and Health Series Report #65 (Geneva: International Labor Office) employed various sources to assemble anthropometric data for 20 world regions. The data provided estimates for the 5th, 50th and 95th percentiles of 19 body dimensions for both genders. In this paper, the method parallel factor analysis (PARAFAC), a natural extension of principal component analysis (PCA) to so-called multi-way array, is performed and favourably compared with the results from PCA. Several comparative studies are performed to justify the use of percentiles rather than individual subject body dimensions. It is found that the outcomes using either are comparable, especially if the body dimensions are mean-centred. Body dimensions related to height (such as stature, buttock–heel length, sitting height and forward reach) are the most critical in describing the international variations; hip breadth showing gender difference is the second most important. People in European regions as well as Australia are the tallest and largest, whereas people in South Indian and Latin American (Indian) regions are the shortest and smallest. The 20 world regions are grouped into four groups that are relatively homogeneous in body dimensions. Potential application of PARAFAC is discussed for the areas in which the data are three-dimensional in nature (such as body dimensions?×?gender/percentile?×?age).     

Observation of Filamentous Nanostructures in Organic‐Inorganic Composite Thin Films Deposited by Co‐Evaporation

Nanostructures are important for a wide area of applications, but are very often difficult to fabricate. A novel and basic approach for controlled nanofilament growth in an organic/inorganic composite material is demonstrated. Thin films of MoO₃‐doped 4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl are grown via vacuum sublimation and analyzed using advanced electron microscopy and spectroscopy techniques. Using electron spectroscopic imaging in the core‐loss and low‐loss regime, MoO₃ agglomerations are identified for different doping concentrations. A 3D reconstruction of the thin film yielded by electron tomography reveals a filamentous structure of MoO₃ within the organic matrix. These filaments are preferentially oriented along the growth direction and are only a few nanometers in diameter. Furthermore, control of the filament growth is possible by changing the substrate temperature because for composites grown on substrates cooled to 120 K MoO₃ agglomeration cannot be detected.     

Modeling Sintering of Multilayers Under Influence of Gravity

There is a tendency for multiple functional ceramic layers used in various applications to have increasing surface areas and decreasing thicknesses. Sintering samples with such geometry is challenging, as differential shrinkage of the layers causes undesired distortions. In this work, a model, which describes the combined effect of sintering and gravity of thin multilayers, is derived and later compared with experimental results. It allows for consideration of both uniaxial and biaxial stress states. The model is based on the Skorohod‐Olevsky viscous sintering framework, the classical laminate theory and the elastic‐viscoelastic correspondence principle. The modeling approach is then applied to illustrate the effect of gravity during sintering of thin layers of cerium gadolinium oxide (CGO), and it is found to be significant.