OSL Characterisation of Two Fluvial Sequences of the River Usmacinta in its Middle Catchment (SE Mexico)

The report summarizes luminescence profiling, initially using a SUERC PPSL system in Mexico, and laboratory analysis at SUERC, used to characterise the stratigraphy and interpret sedimentary processes in terrace deposits of the Usumacinta River, SE Mexico. This was then followed, by quantitative quartz OSL SAR dating of five sediment samples, aimed at defining the chronologicalframework of two sedimentary sequences, USU13-1 and USU13-2. In the wider region, the middle catchment of the Usumacinta River, contains numerous archaeological sites dating to the Maya Classic Period, including Bonampak, Yaxchilan and Piedras Negras. The broader aim of the investigation is to assess whether the two fluvial sequences contain a proxy record of environmental change through the archaeological period of interest. Initial luminescence profiling revealed that the stratigraphy in each profile was complex, reflecting multiple cycles of deposition, with signal maxima, followed by tails to lower intensities, possibly indicating deposition during extreme flood events, interleaved with periods of slower sedimentation, and potentially better luminescence resetting. Laboratory profiling reproduced the apparent maxima/trends in the field profiling dataset, confirming that both sections record complex depositional histories. Furthermore, the variations in stored dose estimates, and luminescence sensitivities with depth, confirm that the sections do not record simple age-depth progressions. Quantitative quartz OSL SAR dating was undertaken on five sediment samples. Given the information obtained from the field- and laboratory-profiles it is not surprising that the equivalent dose distributions for each sample showed considerable scatter, particularly so for the second section, USU13-2. Nevertheless, throughstatistical analysis, individual quartz OSL SAR ages were obtained for each sample. Individual dates fall into the Mayan Post-Classical Period to early modern Period, with statistical combinations pointing to a late 15th century accumulation of USU13-1, and the 18th century accumulation of the sediment within USU13-2. Interestingly, the three samples from section USU13-2, all show some aliquots which tail to higher equivalent doses; furthermore, in each sample, the mean value determined for this component is similar, suggesting that the sediment sampled in USU13-2, may be sourced from a 15th century or older accumulation upstream

Development of antiseptic adaptation and cross-adapatation in selected oral pathogens in vitro

There is evidence that pathogenic bacteria can adapt to antiseptics upon repeated exposure. More alarming is the concomitant increase in antibiotic resistance that has been described for some pathogens. Unfortunately, effects of adaptation and cross-adaptation are hardly known for oral pathogens, which are very frequently exposed to antiseptics. Therefore, this study aimed to determine the in vitro increase in minimum inhibitory concentrations (MICs) in oral pathogens after repeated exposure to chlorhexidine or cetylpyridinium chloride, to examine if (cross-)adaptation to antiseptics/antibiotics occurs, if (cross-)adaptation is reversible and what the potential underlying mechanisms are. When the pathogens were exposed to antiseptics, their MICs significantly increased. This increase was in general at least partially conserved after regrowth without antiseptics. Some of the adapted species also showed cross-adaptation, as shown by increased MICs of antibiotics and the other antiseptic. In most antiseptic-adapted bacteria, cell-surface hydrophobicity was increased and mass-spectrometry analysis revealed changes in expression of proteins involved in a wide range of functional domains. These in vitro data shows the adaptation and cross-adaptation of oral pathogens to antiseptics and antibiotics. This was related to changes in cell surface hydrophobicity and in expression of proteins involved in membrane transport, virulence, oxidative stress protection and metabolism

Low bandgap polymers from fused dithiophene diester

The present invention involves monomeric compounds having the structure: ##STR1## Substituents W and Z are independently --CN, --NO.sub.2, -aryl, -aryl-V, --COX, SO.sub.2 R, --H, or -alkyl. Substituent X is --OR, or --NR,R where R and R.sup.1 are independently -alkyl or --H. Substituent V is -halide, --NO.sub.2, --CN, --SO.sub.2 R, or --COX. At least one of W and Z is --NO.sub.2, --SO.sub.2 R, --CN, --COX or -aryl-V. In one preferred embodiment substituents W and Z are both --CN. In another preferred embodiment, substituent X is --NO.sub.2 or --CN and substituent Z is --C.sub.6 H.sub.4 NO.sub.2. These monomers are polymerized to form low bandgap polymers.Board of Regents, University of Texas Syste

Tactile prints in colour: Studying the Visual Appearance of 2.5D Prints for Heritage Recreations

Printing applications for heritage recreation are a means to allow audiences to appreciate details and engage with cultural materials through closer interaction. A 2.5D print is a media suitable to incorporate visual and tactile qualities such as colour, low relief, textures and roughness. Designing a colour-accurate tactile print requires, nevertheless, anticipating how specific shapes and meso-geometries will affect the reflective properties of the surface, thus changing its appearance. Hence, this paper contributes to improve the understanding of the interaction between geometry and colour when deploying 2.5D prints so that tactile portable replicas can be easily produced. For this, we have produced a series of 2.5D printed patches with varying meso-textures, based on procedural noise functions, and measured their colour coordinates and glossiness. We aim to find a correlation between colour shift (expressed as lightness, chroma and ?E) and the scale and distribution of surface details

Mould Store: Exploring the Preservation of the former Spode Factory’s Post-Industrial Heritage through Digital Technologies

World renowned for its perfection of Bone China and underglaze blue printing techniques, the historic Spode Works in Stoke-on-Trent was one of the few ceramic manufactories in Britain to have operated continuously on its original site until the company ceased trading in 2008 1. In 1987 the legacy of this factory was assigned to the Spode Museum Trust, which currently houses many artefacts associated with the reproduction of the company’s vast design archive spanning over two centuries. Yet, prior to the factory’s closure there was an oversight not to accession the majority of factory’s historic moulds due to their perceived value and the sheer space required to house such material. As ‘by-products’ of ceramic manufacture, moulds are rarely valued or preserved for prosperity; the ‘finished’ ceramic artefact has always taken priority over those objects associated with labour of mass-production. Yet as tools that revolutionised the mechanical reproduction of decorative and functional artefacts, they can illuminate the evolution of important technological and stylistic changes in design and industry that remain relatively under-researched. As the former Spode site is currently in the process of regeneration and its buildings repurposed, only a small percentage of this material has been recommended for retention, with the remainder at risk of disposal. Apart from the time pressures from agencies wishing to regenerate the site, the challenges that exist for the potential documentation of such a sheer volume of material, led to a feasibility study being conducted by a team of interdisciplinary academics in July 2018. The aim of this study was to determine the most appropriate tools for the scanning process and devise an effective workflow system to minimise cost and time. A core sample of mould typologies, materials and technologies from c1850 onwards, were 3D scanned based upon moulds selected for retention by Stoke-on-Trent City Councils Archaeology Service. In the event of pending disposal, digitisation can preserve the shape of an artefact for prosperity, and if needs be, facilitate the physical reproduction of both negative and ‘positive’ ceramic shapes. This session will present work-in-progress, detailing the digital documentation of the ceramic moulds using 3D technologies. The final aim of the project is to archive a large selection of moulds typologies based upon factors such as ‘age, uniqueness, and value in terms of technological developments and the production process’. To further understanding into the complexities of industrial craft practices, the resultant dataset also aims to elucidate material and craft knowledge embodied within such objects. The re-imagining of this data through a contemporary artistic response, that integrates the use of digital technology and traditional know-how will also be discussed. This collaborative project is in conjunction with Staffordshire University, University of Brighton, University College London and Spode Museum Trust. 1 Spode branded wares continue to be made at the Portmeirion factory. Biographies Prof. Neil Brownsword, Professor of Ceramics, Staffordshire University Neil Brownsword is an artist, researcher and educator who holds Professorial positions in ceramics at Staffordshire University and University of Bergen. Brownsword’s practice examines the legacy of globalisation in relation to Stoke-on-Trent’s ceramic manufacturing sector, and the impact this has had upon people, place and traditional skills. His work is represented in public/private collections internationally, including the Victoria and Albert Museum, Korea Ceramic Foundation and the Yingee Ceramic Museum, Taiwan. In 2009 he was awarded the ‘One Off Award’ at the inaugural British Ceramic Biennial, and the Grand Prize at the Gyeonggi International Ceramic Biennale, South Korea in 2015. Prof. Tim Weyrich, Professor of Visual Computing, University College London Tim Weyrich is Professor of Visual Computing at the Department of Computer Science, University College London, Deputy Director of the UCL Centre for Digital Humanities and member of the Steering Board of the Eurographics Workshop on Graphics and Cultural Heritage amongst others. While a computer graphics and computer vision researcher by trade, Tim has a long-standing track record in putting his background in appearance modelling, 3D reconstruction and multi-modal imaging into the service of computational reconstruction and analysis of heritage objects, working with memory institutions and excavations around the world. Dr. Karina Rodriguez Echavarria, Principal Lecturer, University of Brighton Karina Rodriguez Echavarria is a Principal Lecturer at the School of Computing, Engineering and Mathematics at the University of Brighton and member of the Centre for Secure, Intelligent and Usable Systems. She has an interdisciplinary background in computer science and cultural heritage and leads various projects and initiatives in this interdisciplinary area. Her research interests include the development and application of computational technologies for the digitisation of objects and environments; as well as their physical reproduction using digital fabrication

Experimental test of photonic entanglement in accelerated reference frames

The quantization of the electromagnetic field has successfully paved the way for the development of the Standard Model of Particle Physics and has established the basis for quantum technologies. Gravity, however, continues to hold out against physicists' efforts of including it into the framework of quantum theory. Experimental techniques in quantum optics have only recently reached the precision and maturity required for the investigation of quantum systems under the influence of gravitational fields. Here, we report on experiments in which a genuine quantum state of an entangled photon pair was exposed to a series of different accelerations. We measure an entanglement witness for $g$ values ranging from 30 mg to up to 30 g - under free-fall as well on a spinning centrifuge - and have thus derived an upper bound on the effects of uniform acceleration on photonic entanglement. Our work represents the first quantum optics experiment in which entanglement is systematically tested in geodesic motion as well as in accelerated reference frames with acceleration a>>g = 9.81 m/s^2.Comment: 7 pages, 5 figure