Zhoumarshall4038

Sparse-view computed tomography (CT) is a recent approach to reducing the radiation dose in patients and speeding up the data acquisition. Consequently, sparse-view CT has been of particular interest among researchers within the CT community. https://www.selleckchem.com/products/pki587.html Advanced reconstruction algorithms for sparse-view CT, such as iterative algorithms with total-variation (TV), have been studied along with the problem of increasing computational burden and the blurring of artifacts in the reconstructed images. Studies on deep-learning-based approaches applying U-NET have recently achieved remarkable outcomes in various domains including low-dose CT. In this study, we propose a new method for sparse-view CT reconstruction based on a multi-level wavelet convolutional neural network (MWCNN). First, a filtered backprojection (FBP) was used to reconstruct a sparsely sampled sinogram from 60, 120, and 180 projections. Subsequently, the sparse-view data obtained from FBP were fed to a deep-learning network, i.e., the MWCNN. Our network architecture combines a wavelet transform and modified U-NET without pooling. By replacing the pooling function with the wavelet transform, the receptive field is enlarged to improve the performance. We qualitatively and quantitatively evaluated the interpolation, iterative TV method, and standard U-NET in terms of a reduction in the streaking artifacts and a preservation of the anatomical structures. When compared with other methods, the proposed method showed the highest performance based on various evaluation parameters such as the structural similarity, root mean square error, and resolution. These results indicate that the MWCNN possesses a powerful potential for achieving a sparse-view CT reconstruction.Story picture books with examples can be used to teach young children science concepts. Learners can abstract relational information by comparing the analogical examples in the books, leading to a more abstract transferrable understanding of the concept. The purpose of this study was to determine whether manipulating the content or arrangement of the examples included in a picture book would support children's generalization and transfer of a relational concept, namely color camouflage. In total, 81 3-year-olds and 80 4-year-olds were read one of four books at two visits spaced approximately 1 week apart. link2 Examples were manipulated in a 2 (Object Similarity high or low) × 2 (Arrangement interleaved or blocked) design. At each visit, children were asked forced-choice questions with photographs (generalization) and real animals (transfer) and needed to explain their choices. At the first visit, only 3-year-olds who had been read a book with high object similarity displayed generalization and transfer. After they were read the same book again at the second visit, 3-year-olds in all conditions performed above chance on generalization questions but made more correct selections if they had been read the books with blocked examples. The 4-year-olds showed no book-related differences on forced-choice questions at either visit but gave better explanations at the second visit if they had been read interleaved books. Our study provides evidence that picture books with analogical examples can be used to teach children about science but that different types and arrangements of examples may better support children at different ages and with different amounts of prior experience.Humans imitate patently irrelevant actions known as overimitation, and rather than decreasing with age, overimitation increases with age. Whereas most overimitation research has focused on social factors associated with overimitation, comparatively little is known about the cognitive- and task-specific features that influence overimitation. Specifically, developmental contrasts between imitation and overimitation are confounded by the addition of irrelevant actions to causally necessary actions, increasing sequence length, cognitive load, and processing costs-variables known to be age dependent. We constructed a novel puzzle box task such that a four-step imitation, four-step overimitation, and two-step efficient sequence could be demonstrated using the same apparatus on video. In Experiments 1 and 2, 2.5- to 5-year-olds randomly assigned to imitation and overimitation groups performed significantly more target actions than baseline control groups. Rates of imitation and overimitation increased as a function of age, with older preschoolers outperforming younger preschoolers in both conditions. In Experiment 3, preschoolers were shown a video of an efficient two-step demonstration prior to testing. After they responded, they were shown a four-step overimitation video and were tested on the same puzzle box. Children imitated the efficient demonstration, but after watching the overimitation video, they also overimitated the irrelevant actions. Once again, older children overimitated more than younger children. Together, results show that preschoolers are faithful, flexible, and persistent overimitators. The fidelity and flexibility of overimitation are constrained not only by social factors but also by basic cognitive processes that vary across age groups. As these constraints diminish, overimitation and flexible (optimal) imitation increases.Often considered a traditional labour intensive activity, in recent years, the solid waste management (SWM) industry has been largely interested in innovation. Nonetheless, the analysis of innovations in the SW industry is frequently confined to process innovation in the disposal segment, neglecting other kinds of innovation - such as product innovation and organizational innovation - in other segments. While several economic theoretical frameworks have been developed for interpreting eco-innovation in general, a specific analysis of innovation in each segment of SWM is still missing, despite the specificities of this sector. To fill this gap, this paper shows how complexity theory can be profitably used to integrate the more traditional neoclassical approach, offering a comprehensive theoretical framework to analyse innovation in the SWM industry from both a market and firm perspective (the neoclassical approach) and from a social perspective (the complexity theory framework). link3 Four main typologies of the SW market system, exhibiting different kinds of innovation, are outlined (i) a "traditional" landfill-oriented system; (ii) a modern "waste-to-energy" incinerator-oriented system; (iii) a "light recycling" system with integrated solutions and a selection performance that is lower than 50%; and (iv) a "hard recycling" system.Atmospheric greenhouse gas (GHG) concentration increases are a serious problem impacting global climate. Mitigation of agricultural GHG production is crucial as fertilized soils contribute substantially to changes in GHG atmospheric composition. Biochar derived from agricultural or forestry biowaste has been widely used in agriculture and may help mitigate GHG emissions. While different kinds of biochar and their effects on GHG emissions have been studied, feedstock particle size may interact with pyrolysis temperature to impact biochar effects on GHG emissions, but this has not been investigated. Here, feedstock particle size effects on biochar characteristics and soil nitrous oxide (N2O) and carbon dioxide (CO2) emissions were studied using Camellia oleifera fruit shell feedstock with three particle size fractions (0.5-2, 2-5, and 5-10 mm) each pyrolyzed at 300, 450, and 600 °C. Results showed that dissolved organic carbon in biochar increased with particle size when pyrolyzed at 300 °C, but decreased with pyrolysis temperature. The 0.5-2 mm shell-derived biochar was associated with the lowest N2O and CO2 emission rates but the highest net nitrogen mineralization rates compared to 2-5 mm and 5-10 mm shell-derived biochar when pyrolyzed at 300 °C. Overall, shell particle size was more important for soil processes at lower pyrolysis temperatures with less variation among particle sizes at higher pyrolysis temperatures. The results indicated that feedstock particle size may interact with pyrolysis temperature and impact mitigation of soil N2O and CO2 emissions.A comprehensive study was conducted to investigate the pyrolysis characteristics of municipal sludge, and the activation energy of sludge pyrolysis was determined using the Model-free method. The detailed migration characteristics of heavy metals in the pyrolysis products were also investigated at different pyrolysis temperatures (250-850 °C). The results demonstrate that sludge pyrolysis is a multi-step process; the activation energy of pyrolysis increased with the pyrolysis conversion rate, and the average activation energy was calculated as 79.59 kJ mol-1. As the pyrolysis temperature increased, the char yield decreased, the tar yield increased then decreased, and the gas yield increased. At 850 °C, the thermal volatilities of heavy metals followed the sequence Cu less then Cr less then Ni less then Mn less then Pb less then As less then Zn less then Cd = Hg. In addition, Cu, Cr, and Ni were seldom involved in migration during pyrolysis while As, Cd, and Hg readily migrated even at low pyrolysis temperatures. The results provide a theoretical basis for sludge pyrolysis technologies and heavy metals migration control.Used beverage cans (UBĆs) represent one of the largest sources for secondary aluminum production worldwide. Beverage cans are one of the most frequently produced multi-layer packaging materials made of aluminum with an inner epoxy resin coating to prevent direct contact of food and aluminum surface. In the common way of UBĆs recycling, the whole can is re-melted, resulting in the burning and loss of the inner epoxy coating. The use of acidophilic bacteria for the biological leaching of metals has already been well studied, but until now their applications for the selective separation of metal-containing multilayer materials has not been investigated. In this study, the three bioleaching bacteria A. ferrooxidans, A. thiooxidans and A. caldus were explored to selectively leach the aluminum from the epoxy layer, resulting in leaching efficiencies of around 92% after three weeks of incubation. Surface characterization of the epoxy layer after bioleaching application revealed that the nature of the epoxy resin was unchanged, which could allow for recycling. The dissolved aluminum was afterwards selectively precipitated from the lixiviants at pH = 6.5, resulting in aluminum hydroxide precipitation efficiencies of almost 100%. The high leaching efficiencies and the selective precipitation shows the significant potential of acidophilic bacteria in the separation and recycling of multi-layer materials.In-situ catalytic biomass pyrolysis for syngas production is a competitive technology for the recovery of energy in biomass. However, in conventional in-situ catalytic pyrolysis process, the mode of catalyst introduction makes it difficult to separate the catalyst from the char after pyrolysis, resulting in difficulty in catalyst recycling. We considered that the use of monolithic catalyst which has larger size than the biomass feedstock might solve the problem of the separation difficulty between the catalyst and char. In order to verify the feasibility of this strategy, NiO/γ-Al2O3 was respectively supported on ceramic honeycomb, metal foam, and metal wire mesh to produce three monolithic catalysts with different outer surface areas. Their catalytic performance for cattle manure pyrolysis was tested and the result revealed that compared with the granular NiO/γ-Al2O3, using monolithic catalysts with ceramic honeycomb, metal foam, and metal wire mesh carrier respectively increased the gas production by 37%, 33%, and 11%.