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In our paper, we present a performance evaluation of image segmentation algorithms on microscopic image data. In spite of the existence of many algorithms for image data partitioning, there is no universal and ‘the best’ method yet. Moreover, images of microscopic samples can be of various character and quality which can negatively influence the performance of image segmentation algorithms. Thus, the issue of selecting suitable method for a given set of image data is of big interest. We carried out a large number of experiments with a variety of segmentation methods to evaluate the behaviour of individual approaches on the testing set of microscopic images (cross‐section images taken in three different modalities from the field of art restoration). The segmentation results were assessed by several indices used for measuring the output quality of image segmentation algorithms. In the end, the benefit of segmentation combination approach is studied and applicability of achieved results on another representatives of microscopic data category – biological samples – is shown.  相似文献   
817.
Modern society accumulates huge amounts of waste material, particularly in the food industry, where manipulation is usually inadequate and causes a serious ecological problem. As this state is unsustainable and a concern for the future, food by-products must be used as raw materials in further production, because they are often still rich in nutrients or bioactive compounds. This paper provides a comprehensive review of plant food by-product application in animal nutrition around the world. In addition, special attention is paid to ecological benefits, and warns about the potential hazards and negative sides of plant food by-products usage in animal nutrition.  相似文献   
818.
The influence of starter cultures on the free fatty acids content during ripening of Tea sausages, typical dry sausages produced in the south of Croatia, was studied. Three batches of Tea sausages were produced using different starter mixtures (Staphylococcus xylosus S81 and Lactobacillus sakei G20; Staphylococcus xylosus S142 and Lactobacillus sakei G20; Staphylococcus xylosus S206 and Lactobacillus sakei G20), while the control batch was produced without a starter. The amounts of free fatty acids present in the samples at the end of the ripening period were not significantly different, suggesting that the lipolytic enzymes naturally occurring in meat could play a predominant role in the free fatty acids release. Oleic and linoleic acids were present in the highest concentrations, while only small quantities of short-chain fatty acids were detected, with acetic acid being the most representative one.  相似文献   
819.
Liposome-encapsulated folic acid is incorporated into the films made from sodium carboxymethyl cellulose (CMC) (2 mas%) and a mixture of CMC and solagum (9:1 w/w) using the film-forming cast solution method. Histidine is used to increase solubility for folic acid in liposomes (1–5 mg mL−1), and propylene glycol is used as a film plasticizer (2.6 mas%). The obtained films (50–60 µm tick) containing 3.12–20.19 mg of folic acid per gram of film are envisaged to be used as patches for transdermal delivery of folic acid. Therefore, some physical, mechanical, release and structural attributes of the films are scrutinized. Folic acid gives yellow color to the films and contributes to stronger chemical bonds which result in improved strength of the film. Liposomes prolong the release of folic acid from films to 24 h without adverse effects on mechanical properties of the films, but degrade homogeneity of the films, which can be ascribed to its agglomeration within the film matrix as revealed by atomic force microscopy. According to the release at pH 5.5, the film formulation based on a blend of CMC and solagum containing 3 mg mL−1 liposome-encapsulated folic acid is recommended. Practical Application: Folic acid is effective in reducing oxidative stress levels in the skin and neutralizing the harmful free radicals and is also essential for various metabolic reactions in the body. However, the limited solubility of folic acid linked with its poor absorption in an organism, low storage stability, short half-life upon oral consumption, specific food preferences of some people, extensive liver metabolism, and pregnancy-induced vomiting point to a large potential in transdermal usage of folic acid. This has motivated us to design new multicomponent polymer-lipid systems as an alternative solution to overcome some of these drawbacks. The results obtained for these multicomponent films pointed to their potential for prolonged release of folic acid to 24 h, which can also be useful for scientists interested in encapsulating similar poorly soluble compounds in CMC patches. The finding can be also valuable information for pharmaceutical manufacturers and scientists worldwide.  相似文献   
820.
Carbon dots are an emerging class of nanomaterials that has recently attracted considerable attention for applications that span from biomedicine to energy. These photoluminescent carbon nanoparticles are defined by characteristic sizes of <10 nm, a carbon-based core and various functional groups at their surface. Although the surface groups are widely used to establish non-covalent bonds (through electrostatic interactions, coordinative bonds, and hydrogen bonds) with various other (bio)molecules and polymers, the carbonaceous core could also establish non-covalent bonds (π π stacking or hydrophobic interactions) with π-extended or apolar compounds. The surface functional groups, in addition, can be modified by various post-synthetic chemical procedures to fine-tune the supramolecular interactions. Our contribution categorizes and analyzes the interactions that are commonly used to engineer carbon dots-based materials and discusses how they have allowed preparation of functional assemblies and architectures used for sensing, (bio)imaging, therapeutic applications, catalysis, and devices. Using non-covalent interactions as a bottom-up approach to prepare carbon dots-based assemblies and composites can exploit the unique features of supramolecular chemistry, which include adaptability, tunability, and stimuli-responsiveness due to the dynamic nature of the non-covalent interactions. It is expected that focusing on the various supramolecular possibilities will influence the future development of this class of nanomaterials.  相似文献   
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