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21.
This paper deals with the problem of the colorimetric fidelity of digitised colour slides of painted works of art. A six-matrix conversion model was derived that permitted the transformation of any RGB device-dependent measurement on digitised colour slides to XYZ CIE 1931 device-independent values. The model was calibrated against a reference colour chart. Eighty-one uniformly-painted colour samples were photographed together with a painting on a 4 × 5 inch colour slide that was digitised using a high resolution scanner. A 3 × 3 transformation matrix, of the corrected R, G and B values and the respective X, Y and Z tristimulus values provided by spectrophotometry, was calculated. The calculated matrix was then applied to a 13th century Byzantine fresco, captured on the same digitised slide, to transform the RGB measurements to XYZ CIE 1931 device-independent values which were then converted into the L* a* b* CIE 1976 colorimetric system. 相似文献
22.
Margarita Miranda Antonio Vega-Gálvez Purificación García Karina Di Scala John Shi Sophia Xue Elsa Uribe 《Food and Bioproducts Processing》2010,88(2-3):138-144
Aloe vera (Aloe barbadensis Miller) gel was dried at five inlet temperatures 50, 60, 70, 80 and 90 °C, in a convective dryer with a constant air flow of 2.0 ± 0.2 m/s. Rehydration ratio, water holding capacity, texture, microstructure and total polysaccharide content were evaluated. Drying kinetics was estimated using the Weibull distribution (r2 > 0.97 and Chi-square < 0.0009). Values of scale and shape parameters ranged from 90.94 to 341.06 (min) and 1.43 to 1.49, respectively. Furthermore, the influence of temperature on the model parameters as well as on the quality attributes was analysed using a least significant difference test (p-value < 0.05). These effects were more evident for the long drying period (e.g. 810 min at 50 °C). However, minor alterations in the structural properties and total polysaccharide content were produced at drying temperatures of 60–70 °C, resulting in a high quality gel. 相似文献
23.
Expansion of the branch channel to Salzgitter from SKS‐km 3,550 to 14,918 The branch channel to Salzgitter will be extended to the waterway category Vb in the next years. This will enable inland waterway vessels with a width of 11,45 m and a loaded draft of 2,80 m to run it without limitations. The reaches Wedtlenstedt and Üfingen will be extended in most areas to a trapezoidal cross section with a width at water level of 36,90 m and a water depth of 4,00 m. The exit basins of the locks will be extended on one side. Overall about 1 000 000 m2 of soil will be moved. About 300 000 m2 of clay sealing and 460 000 m2 of rip‐rap will be installed. Three culverts have to be replaced by new constructions to adapt to the new cross section of the channel. In addition two bridges will be modified to allow for a clearance of 5,25 m. At present the plan approval procedure is carried out. It is expected to achieve the plan approval order in 2017. The construction is planned to start in 2018. Completion is scheduled for 2024. 相似文献
24.
Smart meters (SM) may provide large benefits to all stakeholders by providing the information required to implement certain sets of demand response actions. Benefits produced by SM related actions depend on the features of these actions, the system and the targeted consumer group.We first lay out an analytical framework to analyze the application of Demand Response (DR) actions. Based on this framework, we describe a way to determine the response of domestic load in a system to the implementation of DR actions. We propose determining the overall change in the consumption behavior of domestic load based on previously obtained estimates of the peak load and overall consumption reduction for different types of consumers in different types of systems resulting from the application of each set of actions. We have carried out a comprehensive literature review to provide here such estimates.We apply the analytical framework and methodology developed to characterize the reaction of consumers in the Austrian system to different SM related actions. Finally, we provide guidelines on which DR actions to implement in this system and how to implement them. The use of advanced indirect feedback on consumption behavior, critical peak prices and simple time-of-use tariffs is advocated. 相似文献
25.
Mauricio Osorio Marcela Carvajal Alejandra Vergara Estefania Butassi Susana Zacchino Carolina Mascayano Margarita Montoya Sophia Mejías Marcelo Cortez-San Martín Yesseny Vsquez-Martínez 《International journal of molecular sciences》2021,22(11)
Prenylated flavonoids are an important class of naturally occurring flavonoids with important biological activity, but their low abundance in nature limits their application in medicines. Here, we showed the hemisynthesis and the determination of various biological activities of seven prenylated flavonoids, named 7–13, with an emphasis on antimicrobial ones. Compounds 9, 11, and 12 showed inhibitory activity against human pathogenic fungi. Compounds 11, 12 (flavanones) and 13 (isoflavone) were the most active against clinical isolated Staphylococcus aureus MRSA, showing that structural requirements as prenylation at position C-6 or C-8 and OH at positions C-5, 7, and 4′ are key to the antibacterial activity. The combination of 11 or 12 with commercial antibiotics synergistically enhanced the antibacterial activity of vancomycin, ciprofloxacin, and methicillin in a factor of 10 to 100 times against drug-resistant bacteria. Compound 11 combined with ciprofloxacin was able to decrease the levels of ROS generated by ciprofloxacin. According to docking results of S enantiomer of 11 with ATP-binding cassette transporter showed the most favorable binding energy; however, more studies are needed to support this result. 相似文献
26.
Sophia X. Sui Lana J. Williams Kara L. Holloway-Kew Natalie K. Hyde Julie A. Pasco 《International journal of molecular sciences》2021,22(1)
Sarcopenia is the loss of skeletal muscle mass and function with advancing age. It involves both complex genetic and modifiable risk factors, such as lack of exercise, malnutrition and reduced neurological drive. Cognitive decline refers to diminished or impaired mental and/or intellectual functioning. Contracting skeletal muscle is a major source of neurotrophic factors, including brain-derived neurotrophic factor, which regulate synapses in the brain. Furthermore, skeletal muscle activity has important immune and redox effects that modify brain function and reduce muscle catabolism. The identification of common risk factors and underlying mechanisms for sarcopenia and cognition may allow the development of targeted interventions that slow or reverse sarcopenia and also certain forms of cognitive decline. However, the links between cognition and skeletal muscle have not been elucidated fully. This review provides a critical appraisal of the literature on the relationship between skeletal muscle health and cognition. The literature suggests that sarcopenia and cognitive decline share pathophysiological pathways. Ageing plays a role in both skeletal muscle deterioration and cognitive decline. Furthermore, lifestyle risk factors, such as physical inactivity, poor diet and smoking, are common to both disorders, so their potential role in the muscle–brain relationship warrants investigation. 相似文献
27.
Ntourmas Anastasios Daskalaki Sophia Dimitriadis Yannis Avouris Nikolaos 《Neural computing & applications》2023,35(7):5587-5587
Neural Computing and Applications - A correction to this paper has been published: https://doi.org/10.1007/s00521-021-05904-z 相似文献
28.
29.
Ye S Discher BM Strzalka J Xu T Wu SP Noy D Kuzmenko I Gog T Therien MJ Dutton PL Blasie JK 《Nano letters》2005,5(9):1658-1667
A family of four-helix bundle peptides were designed to be amphiphilic, possessing distinct hydrophilic and hydrophobic domains along the length of the bundle's exterior. This facilitates their vectorial insertion across a soft interface between polar and nonpolar media. Their design also now provides for selective incorporation of electron donor and acceptor cofactors within each domain. This allows translation of the designed intramolecular electron transfer along the bundle axis into a macroscopic charge separation across the interface. 相似文献
30.
Christopher Anderson Franco Barbanera Mariangiola Dezani-Ciancaglini Sophia Drossopoulou 《Electronic Notes in Theoretical Computer Science》2003,82(8):108
We adapt the aliasing constraints approach for designing a flexible typing of evolving objects. Types are singleton types (addresses of objects, as a matter of fact) whose relevance is mainly due to the sort of safety property they guarantee. In particular we provide a type system for an imperative object based calculus with delegation and which supports method and delegate overriding, addition, and removal. 相似文献