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101.
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We study the shape optimization problem for the paper machine headbox which distributes a mixture of water and wood fibers
in the paper making process. The aim is to find a shape which a priori ensures the given velocity profile on the outlet part.
The mathematical formulation leads to the optimal control problem in which the control variable is the shape of the domain
representing the header, the state problem is represented by the generalized Navier-Stokes system with nontrivial boundary
conditions. This paper deals with numerical aspects of the problem. 相似文献
104.
Jaroslav Jaroš 《Applied Mathematics Letters》2011,24(8):1389-1392
In this paper, a new Picone-type identity for the quasilinear differential operator of the second order is used to establish an integral inequality involving functions and their derivatives which generalizes the classical Wirtinger inequality. 相似文献
105.
The paper presents standard material on A-planar structures and their morphisms. We also introduce the general construction of connections which have the same A-planar curves and characterize some classes of connections obtained in this way. Some of the examples are studied in detail. 相似文献
106.
The use of hydrophilic interaction liquid chromatography (HILIC) in food analysis in the last decade is reviewed. The HILIC mechanism is briefly discussed, but main emphasis is put on the use of HILIC for separation of different food matrices. The food matrices are divided into food of animal origin and related products, vegetables, fruits and related compounds, and other food-related matrices. A list on important applications is provided for each category including experimental conditions and a brief summary of the results. The 100 references included will provide the reader a comprehensive overview and insight into HILIC applications to food analysis. 相似文献
107.
A resin-bound nitroso compound sequestered a single unexpected component from crude plant seed extracts. Several plants, including Piper nigrum, Eugenia caryophyllata, and Pimenta dioica, were extracted with organic solvent in the presence of a nitroso-containing resin. The nitroso resin selectively sequestered a single compound, β-caryophyllene, via a chemo- and regioselective ene reaction. The ene product was released from the resin, and proper selection of the solid-phase linker and cleavage cocktail allowed concomitant further transformation of the primary ene product to a novel functionalized polycycle. Preliminary studies indicate that the new hydroxylamine-containing natural product derivatives have antibiotic activity. 相似文献
108.
Nonlinear Dynamics - In this work, the combination of the 0–1 test for chaos and approximate entropy is applied to a newly established mechanical model instead of the Lyapunov exponent... 相似文献
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Postbiotics are health-promoting microbial metabolites delivered as a functional food or a food supplement. They either directly influence signaling pathways of the body or indirectly manipulate metabolism and the composition of intestinal microflora. Cancer is the second leading cause of death worldwide and even though the prognosis of patients is improving, it is still poor in the substantial part of the cases. The preventable nature of cancer and the importance of a complex multi-level approach in anticancer therapy motivate the search for novel avenues of establishing the anticancer environment in the human body. This review summarizes the principal findings demonstrating the usefulness of both natural and synthetic sources of postbotics in the prevention and therapy of cancer. Specifically, the effects of crude cell-free supernatants, the short-chain fatty acid butyrate, lactic acid, hydrogen sulfide, and β-glucans are described. Contradictory roles of postbiotics in healthy and tumor tissues are highlighted. In conclusion, the application of postbiotics is an efficient complementary strategy to combat cancer. 相似文献