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This study aims to assess the feasibility of delineating and identifying mineral ores from hyperspectral images of tin-tungsten mine excavation faces using machine-learning classification. We compiled a set of hand samples of minerals of interest from a tin-tungsten mine and analyzed two types of hyperspectral images: 1) images acquired with a laboratory set-up under close-to-optimal conditions; and 2) scan of a simulated mine face using a field set-up, under conditions closer to those in the gallery. We have analyzed the following minerals: cassiterite (tin ore), wolframite (tungsten ore), chalcopyrite, malachite, muscovite, and quartz. Classification (Linear Discriminant Analysis, Singular Vector Machines and Random Forest) of laboratory spectra had a very high overall accuracy rate (98%), slightly lower if the 450 – 950 nm and 950 – 1780 nm ranges are considered independently, and much lower (74.5%) for simulated conventional RGB imagery. Classification accuracy for the simulation was lower than in the laboratory but still high (85%), likely a consequence of the lower spatial resolution. All three classification methods performed similarly in this case, with Random Forest producing results of slightly higher accuracy. The user’s accuracy for wolframite was 85%, but cassiterite was often confused with wolframite (user’s accuracy: 70%). A lumped ore category achieved 94.9% user’s accuracy. Our study confirms the suitability of hyperspectral imaging to record the spatial distribution of ore mineralization in progressing tungsten-tin mine faces.

BACKGROUND: The recent identification of embryo cell-free DNA in the spent blastocyst media opened a new era of possibilities for non-invasive embryo aneuploidy testing in assisted reproductive technologies. Yet, previous studies assessing limited numbers of embryos reported variable concordance between embryo cell-free DNA and trophectoderm biopsies, thus questioning the validity of this approach.; OBJECTIVE(S): 1) To evaluate the concordance and reproducibility of testing embryo cell-free DNA versus trophectoderm DNA obtained from the same embryo in a large sample of human blastocysts. 2) To assess the contribution of the inner cell mass and/or trophectoderm to the embryo cell-free DNA released to the culture media.; STUDY DESIGN: This is the interim analysis of a prospective, observational study among eight in vitro fertilization centers, on four continents, to assess consistency between non-invasive embryo aneuploidy testing of embryo cell-free DNA and conventional trophectoderm biopsy. Analysis included 1,301 day-6/7 blastocysts obtained in 406 IVF cycles from 371 patients aged 20-44 years undergoing preimplantation genetic testing for aneuploidy. Fresh oocytes underwent intracytoplasmic sperm injection or in vitro fertilization. No previous assisted hatching or vitrification was allowed before media collection. Individual spent blastocyst medium was collected from embryos cultured at least 40 hours from day 4. After media collection, conventional PGT-A analysis was performed, comprising of trophectoderm biopsy and blastocyst vitrification. Embryo cell-free DNA was analyzed blindly after embryo transfer. Inner cell mass and trophectoderm biopsies were also performed in a subset of 81 aneuploid blastocysts donated for research.; RESULTS: Embryo cell-free DNA analyses were 78.2% (866/1,108) concordant with the corresponding trophectoderm biopsies. No significant differences were detected among centers ranging from 72.5% to 86.3%. Indeed, concordance rates exceeded 86% when all defined steps in the culture laboratory were controlled to minimize the impact of maternal and operator contamination. Sensitivity per center ranged from 76.5% to 91.3%, and specificity from 64.7% to 93.3%. The false-negative rate was 8.3% (92/1,108), and false-positive rate was 12.4% (137/1,108). Interestingly, the two fertilization techniques provided similar sensitivity (80.9% vs. 87.9%) and specificity (78.6% vs. 69.9%). Multivariate analysis did not reveal any bias from patient clinical background, ovarian stimulation protocols, culture conditions, or embryo quality on testing accuracy of concordance. Moreover, concordances of embryo cell-free DNA with trophectoderm and inner cell mass suggest that the embryo cell-free DNA originates from both compartments of the embryo.; CONCLUSION(S): Non-invasive analysis of embryo cell-free DNA analyzed in spent blastocyst culture media demonstrates high concordance with trophectoderm biopsy results in this large multicenter series. A non-invasive approach for prioritizing embryo euploidy offers important advantages such as avoiding invasive embryo biopsy and decreased cost, potentially increasing accessibility for a wider patient population. Copyright © 2020 Elsevier Inc. All rights reserved.

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A combined extended 1D-fuel-bed- and 3D-CFD-model for the simulation of a moving grate wood chip furnace has been developed and validated with experiments. The extended 1D-fuel-bed-model (1D-EFBM) includes, among other things, “thick layer” treatment of the wood chip and fuel nitrogen. During the pyrolysis and the subsequent char gasification nitrogen species are emitted from the fuel bed depending on local temperature and excess air ratio, and on the fuel-nitrogen mass fraction. The temperature within a wood chip is considered inhomogeneous, due to the fact that the top layer of a wood chip interacts with the environment (radiation, convection, etc.). Therefore the temperature on the surface of the wood chip tends to be higher than the core temperature. For the pyrolysis, three competing reactions are considered: Direct gasification to light gases, to tar and light gases, and to char and light gases. The char is later gasified to CO and CO2, whereas the ratio depends on the local temperature regime in the fuel bed. The EDC combustion model is used in the subsequent 3D-CFD simulation with a reduced chemical mechanism. The fuel bed model can be used to predict the influence of operating parameters as e.g. moisture content, on fuel bed behaviour, wood gases production, and N-species production., Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 358-362