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901.
Mikaël Barboteu Weimin Han Stanisław Migórski 《Computers & Mathematics with Applications》2019,77(11):2894-2905
This paper is devoted to numerical analysis of a new class of elliptic variational–hemivariational inequalities in the study of a family of contact problems for elastic ideally locking materials. The contact is described by the Signorini unilateral contact condition and the friction is modeled by a nonmonotone multivalued subdifferential relation allowing slip dependence. The problem involves a nonlinear elasticity operator, the subdifferential of the indicator function of a convex set for the locking constraints and a nonconvex locally Lipschitz friction potential. Solution existence and uniqueness result on the inequality can be found in Migórski and Ogorzaly (2017) . In this paper, we introduce and analyze a finite element method to solve the variational–hemivariational inequality. We derive a Céa type inequality that serves as a starting point of error estimation. Numerical results are reported, showing the performance of the numerical method. 相似文献
902.
Pattern Analysis and Applications - A reliable automatic visual quality assessment of 3D-printed surfaces is one of the key issues related to computer and machine vision in the Industry 4.0 era.... 相似文献
903.
904.
Adriana Nowak Anna Paliwoda Janusz Błasiak 《Critical reviews in food science and nutrition》2019,59(21):3456-3467
AbstractLactobacillus and Bifidobacterium strains, their isolated constituents and substances that they secrete exert various anti-cancer actions, resulting from their anti-proliferative, pro-apoptotic and anti-oxidant properties. They can express and secrete anti-oxidant enzymes, bind reactive oxygen species, release small molecular weight anti-oxidants and chelate transition metals, preventing detrimental actions of many carcinogens. Lactobacillus and Bifidobacterium can interact with proteins regulating the cell cycle inhibiting proliferation of cancer cells, which often are intrinsically resistant to apoptosis. Lactobacilli and bifidobacteria can break this resistance through activation of pro-caspases and downregulation of the anti-apoptotic Bcl-2 and upregulation of pro-apoptotic Bax proteins. Anti-cancer effects of these bacteria can be also associated with their multi-pathways action in the microbiota. However, exact mechanism of their anti-cancer action is poorly known and needs further studies, which are justified by the important role of these bacteria in cancer biology as well as their potential preventive and therapeutic use. 相似文献
905.
906.
Gim Pao Lim Chin Fhong Soon Agnieszka Maria Jastrzębska Nyuk Ling Ma Anita Rozmysłowska Wojciechowska Aleksandra Szuplewska Wan Ibtisam Wan Omar Marlia Morsin Nafarizal Nayan Kian Sek Tee 《Ceramics International》2021,47(16):22567-22577
MXenes are novel 2-D materials which have been extensively investigated for use in advanced biocomposites, water purification, biosensors, bioimaging and antibacterial systems. However, the knowledge associated with the mechanism of cytotoxic response is still limited to lack of verification against 3D spheroid-type cultures. Herein, we present a report on the in vitro cytotoxicity of Ti2CTx MXene against cervical cancer cell lines (HeLa) in a form of 3D spheroid with comparison to 2D cell culture system. Ti2CTx MXenes can be characterized by their multi-layered structure that is produced by the efficient elimination of Al and appearance of the surface functional groups. The biological results with 2D and 3D HeLa indicated that the Ti2CTx MXene was moderately cytotoxic to cells and the cytotoxicity was dose dependent. Our results showed that the toxicity of MXenes is potentially due to direct contact of the Ti2CTx MXene with the cell membrane wall. The Raman spectra suggested that the Ti2CTx MXenes interfered with the cytoplasmic proteins’ conformation and the surrounding microenvironment. This inherently modified the biochemistry of the cell membrane and caused cell apoptosis. This paper contributes to the pool of knowledge regarding the biocompatibility and biophysical properties of Ti2CTx MXene. 相似文献
907.
Piotr Karpiński Bartosz Kruszewski Milena Alicja Stachelska Emilia Szabłowska 《International Journal of Food Science & Technology》2020,55(12):3630-3638
Main aim of this research was to trace the development of volatile profile of Kumpiak podlaski dry-cured ham during traditional curing and ripening for 30 weeks. Volatiles were extracted from each 6-week period of ripening, and overall fifty-three aroma compounds were identified. Changes in chemical groups share between cured and fully ripened ham were observed: aldehydes (35.49 → 31.37%), ketones (25.18 → 14.62%), alcohols (17.97 → 15.74%), esters (3.37 → 12.04%), hydrocarbons (7.69 → 6.81%), fatty acids (0.02 → 0.53%), terpenes (2.26 → 9.70%) and heterocyclic aromatic compounds (0.99 → 0.78%). The 18th week of ripening is crucial for the aroma of Kumpiak podlaski ham due to start of continuous decrease in ketones and increase in esters’ and terpenes’ share. Formation of esters and terpenes originated from the presence of local herbs and the development of microflora. Principal component analysis (PCA) showed clear separation of samples from each 6-week period of ripening. Obtained results relying on thirty-seven compounds enabled to make a preliminary determination of ripening markers. 相似文献
908.
Pajor Krzysztof Rutkowski Bogdan Gondek Łukasz Błyskun Piotr Reehuis Manfred Wieczerzak Krzysztof Kozieł Tomasz 《Metallurgical and Materials Transactions A》2022,53(8):2902-2925
Metallurgical and Materials Transactions A - Glass-forming alloys are very sensitive to oxygen contaminations. Here, the oxygen-scavenging effect of five rare-earth elements (REEs) was studied when... 相似文献
909.
Multimedia Tools and Applications - In recent years many methods have been proposed for eye detection. In some cases however, such as driver drowsiness detection, lighting conditions are so... 相似文献
910.