Integrating photovoltaic cells into decorative architectural glass using traditonal glasspainting techniques and fluorescent dyes

Photovoltaic cells can be integrated into decorative glass, providing a showcase for this renewable technology, whilst assisting in the creation of sustainable architecture through generation of electricity from the building surface. However, traditional, opaque, square, crystalline-silicon solar cells contrast strongly with their surroundings when incorporated into translucent, coloured glazing. Methods of blending photovoltaic cells into their surroundings were developed, using traditional glass painting techniques. A design was created in which opaque paint was applied to the areas of glass around underlying photovoltaic cells. Translucent, platinum paint was used on the glass behind the photovoltaic cells. This covered the grey cell backs whilst reflecting light and movement. The platinum paint was shown to cause a slight increase in power produced by photovoltaic cells placed above it. To add colour, very small amounts of Lumogen F dye (BASF) were incorporated into a silicone encapsulant (Dow Corning, Sylgard 184), which was then used hold photovoltaic cells in place between sheets of painted glass. Lumogen dyes selectively absorb and emit light, giving a good balance between colour addition and electricity production from underlying photovoltaic cells. When making sufficient quantities of dyed encapsulant for a 600 x 450 mm test piece, the brightness of the dye colours faded, and fluorescence decreased, although some colour was retained. Improvement of the method, including testing of alternative encapsulant materials, is required, to ensure that the dyes continue to fluoresce within the encapsulant. In contrast, the methods of adding opacity variation to glass, through use of glass painting, are straightforward to develop for use in a wide variety of photovoltaic installations. Improvement of these methods opens up a wide variety of architectural glass design opportunities with integrated photovoltaics, providing an example of one new medium to make eco-architecture more aesthetically pleasing, whilst generating electricity

Creative use of BIPV materials: barriers and solutions

Inventive use of photovoltaic (PV) materials in architecture can be developed through use of PV in artworks. This is particularly important in increasing the uptake of building-integrated building-integrated photovoltaics (BIPV), by developing novel methods of combining and installing PV materials. Current examples of PV artwork and design are examined, from small to large scale, to assess the current design limitations. The design of two PV artworks is discussed in detail, including an artwork that uses the principle of the luminescent solar concentrator (LSC), to show the way in which design hurdles are discovered and overcome. Challenges range from difficulties in obtaining small quantities of PV materials; the balance between efficiency and artistic effect; through to technical and siting issues that an artist must address when designing a functional PV structure. Methods of overcoming these barriers are explored, including the use of lumogen dyes in encapsulant materials

Distribution and characterisation of Glucagon-like peptide-1 receptor expressing cells in the mouse brain.

© 2015 The Authors.Objective: Although Glucagon-like peptide 1 is a key regulator of energy metabolism and food intake, the precise location of GLP-1 receptors and the physiological relevance of certain populations is debatable. This study investigated the novel GLP-1R-Cre mouse as a functional tool to address this question. Methods: Mice expressing Cre-recombinase under the Glp1r promoter were crossed with either a ROSA26 eYFP or tdRFP reporter strain to identify GLP-1R expressing cells. Patch-clamp recordings were performed on tdRFP-positive neurons in acute coronal brain slices from adult mice and selective targeting of GLP-1R cells in vivo was achieved using viral gene delivery. Results: Large numbers of eYFP or tdRFP immunoreactive cells were found in the circumventricular organs, amygdala, hypothalamic nuclei and the ventrolateral medulla. Smaller numbers were observed in the nucleus of the solitary tract and the thalamic paraventricular nucleus. However, tdRFP positive neurons were also found in areas without preproglucagon-neuronal projections like hippocampus and cortex. GLP-1R cells were not immunoreactive for GFAP or parvalbumin although some were catecholaminergic. GLP-1R expression was confirmed in whole-cell recordings from BNST, hippocampus and PVN, where 100 nM GLP-1 elicited a reversible inward current or depolarisation. Additionally, a unilateral stereotaxic injection of a cre-dependent AAV into the PVN demonstrated that tdRFP-positive cells express cre-recombinase facilitating virally-mediated eYFP expression. Conclusions: This study is a comprehensive description and phenotypic analysis of GLP-1R expression in the mouse CNS. We demonstrate the power of combining the GLP-1R-CRE mouse with a virus to generate a selective molecular handle enabling future in vivo investigation as to their physiological importance

Improving the aesthetics of photovoltaics in decorative architectural glass

Increasing colour variety in photovoltaics can improve the uptake of this renewable technology, which is vital to the creation of sustainable architecture. However, the introduction of colour into photovoltaics often involves increased cost and decreased efficiency. A method was found to add colour to photovoltaics, using luminescent materials: fluorescent organic dyes (BASF Lumogen). These selectively absorb and emit light, giving a good balance between colour addition and electricity production from underlying photovoltaic cells. Very small amounts of Lumogen dye were added to a silicone encapsulant (Dow Corning Sylgard 184), which was then used hold photovoltaic cells in place between sheets of painted glass. When making sufficient quantities of dyed encapsulant for a 600 x 450 mm testpiece, the dye colours faded, with low levels of fluorescence, although some colour was retained. Improvement of the method, including testing of alternative encapsulant materials, is required, to ensure that the dyes continue to fluoresce within the encapsulant. Although the Lumogen dyes are quite stable when compared to other dye molecules, in general organic dyes are not yet sufficiently durable to make this technology viable for installations that are to last for more than 20 years: the guaranteed lifetime of standard photovoltaic modules. Dye replenishment, or replacement of materials, will be required; or a product with a shorter ‘useful’ lifetime identified. This method opens up a wide variety of architectural glass design opportunities that incorporate photovoltaics, providing an example of one new medium to make eco-architecture more aesthetically pleasing, whilst generating electricity

A silicone host for Lumogen dyes

Altering the encapsulant colour in photovoltaic (PV) modules is a straightforward way of achieving greater colour range whilst minimising additional cost in PV systems. Lumogen fluorescent, organic dyes offer a way of adding colour to the encapsulant with minimal change in efficiency. The silicone encapsulant material Sylgard 184 is tested as a host material for Lumogen dyes. A method of dissolving various Lumogen dyes in Sylgard is investigated, and limits of solubility are explored. Methods of preparing samples suitable for optical measurements are found. Optical density is measured for a range of dye concentrations. The results indicate that Lumogen dyes can be dissolved successfully within Sylgard 184, giving good optical properties for lower dye concentrations. Initial photoluminescent quantum yield measurements confirm that Lumogen dyes can function effectively within a Sylgard host. This is promising for use of this material combination in the creation of coloured, fluorescent PV encapsulant layers

The search for building-integrated PV materials with good aesthetic potential: a survey

Building-integrated photovoltaics (PV) is currently dominated by blue and black rectilinear forms. Greater variety of colour and form could lead to much better uptake of PV in the built environment, also increasing the potential for PV to be used as an artistic material. Listing the available PV technologies by colour gives a clearer picture of the current situation. An assessment of photostability, efficiency and price, for each material, indicates the materials that have the potential to fill the gaps in the colour spectrum. Use of combinations of materials that can be fabricated in different ways from the current, standardised, PV modules will further increase the possibilities for use in building integration, Extending the lifetimes of organic PV, dye-sensitised PV or luminescent solar concentrators will increase the possibilities for development of new PV products

Improving the aesthetics of photovoltaics through use of coloured encapsulants

Photovoltaics (solar cells) are important in the creation of sustainable architecture, but are difficult to integrate into a wide variety of architectural styles, which is necessary if this technology is to be extensively used. Adding variety to the colour range in these installations will provide a way of making this solar energy technology more visually exciting, so methods need to be found to add colour at minimal extra cost, without loss of efficiency. Adding colour to photovoltaic encapsulant materials offers a solution. It is shown that fluorescent, organic Lumogen dyes (BASF) can be added to the photovoltaic encapsulant materials Sylgard 184 (Dow Corning) and EVA (Ethylene Vinyl Acetate). The dyes continue to fluoresce within these host materials. Encapsulating a photovoltaic cell with Sylgard containing Lumogen red 300 dye (BASF) demonstrates that light can be transported to a photovoltaic cell by the fluorescent dyes inside the encapsulant material that surrounds the cell. This slightly improves the electricity output from the photovoltaic cell, and is especially promising for use in light-transmissive photovoltaic arrays incorporating widely-spaced photovoltaic cells, such as architectural glass art that incorporates photovoltaics. Further work is needed to test and improve the performance of the dyes over time, to ensure that installations incorporating this technology can last for the minimum twenty years that is the current industry standard for photovoltaics

Brain activation during face perception: evidence of a developmental change.

Behavioral studies suggest that children under age 10 process faces using a piecemeal strategy based on individual distinctive facial features, whereas older children use a configural strategy based on the spatial relations among the face's features. The purpose of this study was to determine whether activation of the fusiform gyrus, which is involved in face processing in adults, is greater during face processing in older children (12-14 years) than in younger children (8-10 years). Functional MRI scans were obtained while children viewed faces and houses. A developmental change was observed: Older children, but not younger children, showed significantly more activation in bilateral fusiform gyri for faces than for houses. Activation in the fusiform gyrus correlated significantly with age and with a behavioral measure of configural face processing. Regions believed to be involved in processing basic facial features were activated in both younger and older children. Some evidence was also observed for greater activation for houses versus faces for the older children than for the younger children, suggesting that processing of these two stimulus types becomes more differentiated as children age. The current results provide biological insight into changes in visual processing of faces that occur with normal development

A pragmatic randomised controlled trial of hydrotherapy and land exercises on overall well being and quality of life in rheumatoid arthritis

Background \ud Hydrotherapy is highly valued by people with rheumatoid arthritis yet few studies have compared the benefits of exercises in heated water against exercises on land. In particular, data on quality of life is rarely reported. This is especially important because patients treated with hydrotherapy often report an enhanced sense of well-being. We report a randomised controlled trial in which we compared the effects of hydrotherapy with exercises on land on overall response to treatment, physical function and quality of life in patients with rheumatoid arthritis. \ud \ud Methods \ud One hundred and fifteen patients with RA were randomised to receive a weekly 30-minute session of hydrotherapy or similar exercises on land for 6 weeks. Our primary outcome was a self-rated global impression of change – a measure of treatment effect on a 7-point scale ranging from 1(very much worse) to 7 (very much better) assessed immediately on completion of treatment. Secondary outcomes including EuroQol health related quality of life, EuroQol health status valuation, HAQ, 10 metre walk time and pain scores were collected at baseline, after treatment and 3 months later. Binary outcomes were analysed by Fisher's exact test and continuous variables by Wilcoxon or Mann-Whitney tests. \ud \ud Results \ud Baseline characteristics of the two groups were comparable. Significantly more patients treated with hydrotherapy (40/46, 87%) were much better or very much better than the patients treated with land exercise (19/40, 47.5%), p < 0.001 Fisher's exact test. Eleven patients allocated land exercise failed to complete treatment compared with 4 patients allocated hydrotherapy (p = 0.09). Sensitivity analyses confirmed an advantage for hydrotherapy if we assumed non-completers would all not have responded (response rates 70% versus 38%; p < 0.001) or if we assumed that non-completers would have had the same response as completers (response rates 82% versus 55% p = 0.002). Ten metre walk time improved after treatment in both cases (median pre-treatment time for both groups combined 10.9 seconds, post-treatment 9.1 s, and 3 months later 9.6 s). There was however no difference between treatment groups. Similarly there were no significant differences between groups in terms of changes to HAQ, EQ-5D utility score, EQ VAS and pain VAS. \ud \ud Conclusion \ud Patients with RA treated with hydrotherapy are more likely to report feeling much better or very much better than those treated with land exercises immediately on completion of the treatment programme. This perceived benefit was not reflected by differences between groups in 10-metre walk times, functional scores, quality of life measures and pain scores