123 research outputs found

    CONVENTIONAL OR AUTOMATED PHOTOGRAMMETRY FOR CULTURAL HERITAGE DOCUMENTATION?

    Get PDF
    During the past 15 years photogrammetric practice has experienced an unprecedented change by the influence of computer vision algorithms, which support an almost completely automated processing. It is widely acknowledged that this fact has “democratized” Photogrammetry a lot, in the sense that it has become almost everyone’s tool. However, this radical change has been met by scepticism by traditional photogrammetrists, who claim that such tools may lead to geometrically wrong and inaccurate results if not accompanied by thorough projection and error checks and evaluation of the correctness of results.In this paper, the two approaches are briefly described on the basis of the geometric documentation of a cultural heritage funerary monument situated in the archaeological site of Messini in Southern Greece. An effort is made for highlighting the obvious advantages of each approach but also indicating their disadvantages. Applications, subject to different requirements and processing procedures are identified, rationalizing that conventional photogrammetric procedures still cannot be easily replaced.</p

    XR-RF Imaging Enabled by Software-Defined Metasurfaces and Machine Learning: Foundational Vision, Technologies and Challenges

    Full text link
    We present a new approach to Extended Reality (XR), denoted as iCOPYWAVES, which seeks to offer naturally low-latency operation and cost-effectiveness, overcoming the critical scalability issues faced by existing solutions. iCOPYWAVES is enabled by emerging PWEs, a recently proposed technology in wireless communications. Empowered by intelligent (meta)surfaces, PWEs transform the wave propagation phenomenon into a software-defined process. We leverage PWEs to i) create, and then ii) selectively copy the scattered RF wavefront of an object from one location in space to another, where a machine learning module, accelerated by FPGAs, translates it to visual input for an XR headset using PWEdriven, RF imaging principles (XR-RF). This makes for an XR system whose operation is bounded in the physical layer and, hence, has the prospects for minimal end-to-end latency. Over large distances, RF-to-fiber/fiber-to-RF is employed to provide intermediate connectivity. The paper provides a tutorial on the iCOPYWAVES system architecture and workflow. A proof-of-concept implementation via simulations is provided, demonstrating the reconstruction of challenging objects in iCOPYWAVES produced computer graphics

    Towards elucidating carnosic acid biosynthesis in Lamiaceae: Functional characterization of the three first steps of the pathway in Salvia fruticosa and Rosmarinus officinalis

    Get PDF
    Carnosic acid (CA) is a phenolic diterpene with anti-tumour, anti-diabetic, antibacterial and neuroprotective properties that is produced by a number of species from several genera of the Lamiaceae family, including Salvia fruticosa (Cretan sage) and Rosmarinus officinalis (Rosemary). To elucidate CA biosynthesis, glandular trichome transcriptome data of S. fruticosa were mined for terpene synthase genes. Two putative diterpene synthase genes, namely SfCPSand SfKSL, showing similarities to copalyl diphosphate synthase and kaurene synthase-like genes, respectively, were isolated and functionally characterized. Recombinant expression in Escherichia coli followed by in vitro enzyme activity assays confirmed that SfCPS is a copalyl diphosphate synthase. Coupling of SfCPS with SfKSL, both in vitro and in yeast, resulted in the synthesis miltiradiene, as confirmed by 1D and 2D NMR analyses (1H, 13C, DEPT, COSY H-H, HMQC and HMBC). Coupled transient in vivo assays of SfCPS and SfKSL in Nicotiana benthamiana further confirmed production of miltiradiene in planta. To elucidate the subsequent biosynthetic step, RNA-Seq data of S. fruticosa and R. officinalis were searched for cytochrome P450 (CYP) encoding genes potentially involved in the synthesis of the first phenolic compound in the CA pathway, ferruginol. Three candidate genes were selected, SfFS, RoFS1 and RoFS2. Using yeast and N. benthamiana expression systems, all three where confirmed to be coding for ferruginol synthases, thus revealing the enzymatic activities responsible for the first three steps leading to CA in two Lamiaceae genera

    Sugar-added beverages consumption among kindergarten children of Crete: effects on nutritional status and risk of obesity

    Get PDF
    <p>Abstract</p> <p>Objective</p> <p>To assess the intake of sugar-added beverages such as soft drinks and commercially available fruit juices in kindergarten children, and to examine its association with obesity indices, physical activity levels and dietary habits.</p> <p>Methods</p> <p>A total of 856 children aged 4–7 years living in Crete, Greece in 2004–5 were included in this cross-sectional study. Nutrient and food intake was assessed with the use of 3-day weighed food records. Body measurements were used in order to assess BMI and waist circumference, and moderate-to-vigorous physical activity was calculated with the use of a questionnaire.</p> <p>Results</p> <p>Approximately 59.8% of all children consumed sugar-added beverages on a daily basis. High intake of sugar-added beverages (> 250 g/day) was associated with low intakes of calcium (p < 0.001), vitamin A and E (p < 0.010), fruits and vegetables (p = 0.007), and milk and yogurt (p = 0.048). Compared to non or low consumers, high consumers of sugar-added beverages (> 250 g/day) had higher BMI levels and two times greater risk of being overweight and/or obese (OR:2.35, p = 0.023).</p> <p>Conclusion</p> <p>High intake of sugar-added beverages in kindergarten children is associated with poor eating habits and inadequate nutrient intake, as well as increased risk for developing childhood obesity.</p

    Distinct triterpene synthases in the laticifers of Euphorbia lathyris

    Get PDF
    Abstract Euphorbia lathyris was proposed about fifty years ago as a potential agroenergetic crop. The tremendous amounts of triterpenes present in its latex has driven investigations for transforming this particular biological fluid into an industrial hydrocarbon source. The huge accumulation of terpenes in the latex of many plant species represent a challenging question regarding cellular homeostasis. In fact, the enzymes, the mechanisms and the controllers that tune the amount of products accumulated in specialized compartments (to fulfill ecological roles) or deposited at important sites (as essential factors) are not known. Here, we have isolated oxidosqualene cyclases highly expressed in the latex of Euphorbia lathyris. This triterpene biosynthetic machinery is made of distinct paralogous enzymes responsible for the massive accumulation of steroidal and non-steroidal tetracyclic triterpenes. More than eighty years after the isolation of butyrospermol from shea butter (Heilbronn IM, Moffet GL, and Spring FS J. Chem. Soc. 1934, 1583), a butyrospermol synthase is characterized in this work using yeast and in folia heterologous expression assays

    The risks of acute exposure to black carbon in Southern Europe: Results from the med-particles project

    Get PDF
    Objectives: While several studies have reported associations of daily exposures to PM2.5 (particles less than 2.5 μm) with mortality, few studies have examined the impact of its constituents such as black carbon (BC), which is also a significant contributor to global climate change. Methods: We assessed the association between daily concentrations of BC and total, cardiovascular and respiratory mortality in two southern Mediterranean cities. Daily averages of BC were collected for 2 years in Barcelona, Spain and Athens, Greece. We used case-crossover analysis and examined single and cumulative lags up to 3 days. Results: We observed associations between BC and all mortality measures. For a 3-day moving average, cardiovascular mortality increased by 4.5% (95% CI 0.7 to 8.5) and 2.0% (95% CI 0 to 4.0) for an interquartile change in BC in Athens and Barcelona, respectively. Considerably higher effects for respiratory mortality and for those above age 65 were observed. In addition, BC exhibited much greater toxicity per microgram than generic PM2.5. Conclusions: Our findings suggest that BC, derived in western industrialised nations primarily from diesel engines and biomass burning, poses a significant burden to public health, particularly in European cities with high-traffic density.Peer reviewe
    corecore