Developing tools and evidence to deliver prosperity: optimising for prosperity with a meta-framework for change

Change is persistent, and provisioning for prosperity in this complex dynamic world is not a simple task. Sustaining the conditions which enable certain prosperities can come at the expense of others whilst undermining the biophysical foundations required for all. In this paper I explore the tension between this need for sustainment and the inevitability of change by examining several conceptualisations and formalised frameworks for change which range from the holistic to the mechanistic. I find that both prosperity and resilience in human systems are contingent on the skilful nurturing of the novelty emergent from the great diversity of knowledges at our collective disposal. With this assertion in hand, I attempt to design and assemble a meta-framework for change that can describe our dynamic world and gesture it towards a future of equitably co-existing prosperities through a craft of emergence. Following this and a hypothetical example of the meta-framework in action, I conclude that it can indeed be a useful tool provided it can bare the weight of further scrutiny and integration with other approaches

Fabrication of difficult nanostructures by injection moulding

There is an increasing demand for nanostructured polymeric surfaces for many scientific and commercial applications including the fields of cell and tissue engineering, where the study of the ways that cells interact with their environment holds great potential for the future of regenerative medicine. Current replication based fabrication techniques, such as hot embossing, which are used to produce nanostructured surfaces for this type of research are not fast enough to keep up with the growing demand for them. Injection moulding offers a high throughput alternative to these processes and can upscale the production of nanopatterned samples by several orders of magnitude. However, the nickel moulds traditionally used to injection mould micro- and nanostructures are limited to producing recessed features due to the rate at which the injected polymer cools upon contact with it. In order to replicate raised features (e.g. pillars) the polymer needs enough time to fill the nanoscale cavities of the mould before freezing. A solution to this limitation of nickel tooling is devised and implemented, using a thermally insulating tooling material that facilitates the formation of nanopillars by injection moulding. This tooling material can be patterned by a range of fabrication techniques including photolithography and nanoimprint lithography. The tooling can be used to replicate nanopatterns over underlying micron and millimetre scale topographies. This flexible solution enables the large volume production of samples containing raised poly(carbonate) nanopillars without significantly compromising cycle time. Following this, the technique is adapted in an attempt to replicate high aspect ratio nanostructures. In this section a range of non-adhesive surface coatings are tested for their abilities to enhance the replication process through the systematic analysis of their durability and the replication fidelity that they enable. Nanopillars with aspect ratios of greater than 10:1 are successfully produced and are used to fabricate surfaces for cell engineering research. This success is also demonstrative of the technique’s potential to mass produce nanostructures for other applications such as non-reflective and dry adhesive surfaces. Finally, a study is undertaken to replicate microstructures with an elastomeric polymer. The tooling solution is used to assess the minimum feature size that can be replicated with this polymer and how processing parameters and non-adhesive coatings can improve this. This thesis documents the development of a range of enabling techniques which add to the existing toolbox of nanofabrication technologies. They address a growing demand for nanostructured polymeric surfaces in cell and tissue engineering research, whilst remaining open and adaptable to any application that requires the high throughput production of nanopatterned polymeric samples

Self-folding nano- and micropatterned hydrogel tissue engineering scaffolds by single step photolithographic process

Current progress in tissue engineering is focused on the creation of environments in which cultures of relevant cells can adhere, grow and form functional tissue. We propose a method for controlled chemical and topographical cues through surface patterning of self-folding hydrogel films. This provides a conversion of 2D patterning techniques into a viable method of manufacturing a 3D scaffold. While similar bilayers have previously been demonstrated, here we present a faster and high throughput process for fabricating self-folding hydrogel devices incorporating controllable surface nanotopographies by serial hot embossing of sacrificial layers and photolithography

Label-free segmentation of co-cultured cells on a nanotopographical gradient

The function and fate of cells is influenced by many different factors, one of which is surface topography of the support culture substrate. Systematic studies of nanotopography and cell response have typically been limited to single cell types and a small set of topographical variations. Here, we show a radical expansion of experimental throughput using automated detection, measurement, and classification of co-cultured cells on a nanopillar array where feature height changes continuously from planar to 250 nm over 9 mm. Individual cells are identified and characterized by more than 200 descriptors, which are used to construct a set of rules for label-free segmentation into individual cell types. Using this approach we can achieve label-free segmentation with 84% confidence across large image data sets and suggest optimized surface parameters for nanostructuring of implant devices such as vascular stents

A wavelet algorithm for the solution of a singular integral equation over a smooth two-dimensional manifold

In this paper we consider a piecewise bilinear collocation method for the solution of a singular integral equation over a smooth surface. Using a fixed set of parametrizations, we introduce special wavelet bases for the spaces of test and trial functions. The trial wavelets have two vanishing moments only if their supports do not intersect the lines belonging to the common boundary of two subsurfaces defined by different parameter representations. Nevertheless, analogously to wellknown results on wavelet algorithms, the stiffness matrices with respect to these bases can be compressed to sparse matrices such that the interative solution of the matrix equations becomes fast. Finally, we present a fast quadrature algorithm for the computation of the compressed stiffness matrix. (orig.)Available from TIB Hannover: RR 5549(267)+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

An application of the simultaneous approximation in combinatorial optimization

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

3D printed tooling for injection moulded microfluidics

Microfluidics have been used for several decades to conduct a wide range of research in chemistry and the life sciences. The reduced dimensions of these devices give them advantages over classical analysis techniques such as increased sensitivity, shorter analysis times, and lower reagent consumption. However, current manufacturing processes for microfluidic chips either limits them to materials with unwanted properties, or are not cost effective enough for rapid-prototyping approaches. Here we show that inlays for injection moulding can be 3D printed, thus reducing the skills, cost, and time required for tool fabrication. We demonstrate the importance of orientation of the part during 3D printing so that features as small as 100 x 200 μm can be printed. We also demonstrate that the 3D printed inlay is durable enough to fabricate at least 500 parts. Furthermore, devices can be designed, manufactured, and tested within one working day. Finally, as demonstrators we design and mould a microfluidic chip to house a plasmonic biosensor as well as a device to house liver organoids showing how such chips can be used in organ-on-a-chip applications. This new fabrication technique bridges the gap between small production and industrial scale manufacturing, whilst making microfluidics cheaper, and more widely accessible

Realising the environmental potential of vertical farming systems through advances in plant photobiology

Intensive agriculture is essential to feed increasing populations, yet requires large amounts of pesticide, fertiliser, and water to maintain productivity. One solution to mitigate these issues is the adoption of Vertical Farming Systems (VFS). The self-contained operation of these facilities offers the potential to recycle agricultural inputs, as well as sheltering crops from the effects of climate change. Recent technological advancements in light-emitting diode (LED) lighting technology have enabled VFS to become a commercial reality, although high electrical consumption continues to tarnish the environmental credentials of the industry. In this review, we examine how the inherent use of electricity by VFS can be leveraged to deliver commercial and environmental benefits. We propose that an understanding of plant photobiology can be used to vary VFS energy consumption in coordination with electrical availability from the grid, facilitating demand-side management of energy supplies and promoting crop yield

Adhesion of Escherichia Coli to Nanostructured Surfaces and the Role of Type 1 Fimbriae

Bacterial fimbriae are an important virulence factor mediating adhesion to both biotic and abiotic surfaces and facilitating biofilm formation. The expression of type 1 fimbriae of Escherichia coli is a key virulence factor for urinary tract infections and catheter-associated urinary tract infections, which represent the most common nosocomial infections. New strategies to reduce adhesion of bacteria to surfaces is therefore warranted. The aim of the present study was to investigate how surfaces with different nanotopography-influenced fimbriae-mediated adhesion. Surfaces with three different nanopattern surface coverages made in polycarbonate were fabricated by injection molding from electron beam lithography nanopatterned templates. The surfaces were constructed with features of approximately 40 nm width and 25 nm height with 100 nm, 250 nm, and 500 nm interspace distance, respectively. The role of fimbriae type 1-mediated adhesion was investigated using the E. coli wild type BW25113 and ΔfimA (with a knockout of major pilus protein FimA) and ΔfimH (with a knockout of minor protein FimH) mutants. For the surfaces with nanotopography, all strains adhered least to areas with the largest interpillar distance (500 nm). For the E. coli wild type, no difference in adhesion between surfaces without pillars and the largest interpillar distance was observed. For the deletion mutants, increased adhesion was observed for surfaces without pillars compared to surfaces with the largest interpillar distance. The presence of a fully functional type 1 fimbria decreased the bacterial adhesion to the nanopatterned surfaces in comparison to the mutants

Protein-coated nanostructured surfaces affect the adhesion of Escherichia coli

Developing new implant surfaces with anti-adhesion bacterial properties used for medical devices remains a challenge. Here we describe a novel study investigating nanotopography influences on bacterial adhesion on surfaces with controlled interspatial nanopillars distances. Surfaces were coated with proteins (fibrinogen, collagen, serum and saliva) prior to E. coli-WT adhesion under flow conditions. PiFM provided chemical mapping and showed that proteins adsorbed both between and onto the nanopillars with a preference to areas between the nanopillars. E. coli-WT adhered least to protein-coated areas with low surface nanopillar coverage, most to surfaces coated with saliva, while human serum led to the lowest adhesion. Protein-coated nanostructured surfaces affected the adhesion of E. coli-WT. Abstract text goes here