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Twenty‐five strains, isolated from raw, non‐pasteurised, organic whey samples, were identified phenotypically and genotypically. Biochemical tests were performed, and enzyme profiles, antibiotic resistance and antimicrobial properties were investigated. Sixteen strains were identified as genus Lactobacillus. Based on 16S rDNA gene sequence, the strains were identified as Lb. plantarum and Lb. fermentum. All of the strains had β‐galactosidase activity, and some of them reduced nitrate content. All strains utilised carbohydrates. The tested strains were characterised by low or average lipolytic and esterolytic activity. Moreover, the strains showed low proteolytic activity which is advantageous for their use as starter cultures for foods with low protein content. Strains Lb. fermentum S20, SM1, SM3, S2R and Lb. plantarum SM5 produced harmful N‐acetyl‐β‐glucosaminidase; moreover, the strain S20 produced also β‐glucuronidase. None of the strains produced α‐chymotrypsin. In phenotypic studies, most of the test strains were susceptible to gentamicin, ampicillin, tetracycline, chloramphenicol, penicillin and erythromycin. Strains Lb. plantarum S1 and Lb. fermentum S4, S7, S8, S10, SM1 and SM3 did not possess any transfer resistance genes. Antagonistic activity of the culture LAB strains was assessed as high or moderate in relation to the indicator strains, with the greatest zones of inhibition for E.coli and the smallest for L. monocytogenes ATCC 15313. This study reveals that the LAB strains isolated from organic whey have high potential for food application. Some strains of species Lb. fermentum (S4, S7, S8, S10) have been identified as the best candidates.  相似文献   
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The article presents the results of research on the use of the new technology of friction welding with a non-wearing tool for welding pipe ends with lids. The pipes and lids were made of aluminium alloy EN AW 2017A, non-weldable by conventional methods. The aim of the study was to verify the possibility of welding the lid to the pipe using the FSW method as well as a new method with a tool with specially profiled friction surface. The article presents the results of structural tests and strength tests of the weld joints obtained using the new technique.  相似文献   
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The sugar fucose plays a myriad of roles in biological recognition. Enzymes hydrolyzing fucose from glycoconjugates, α-l -fucosidases, are important targets for inhibitor and probe development. Here we describe the synthesis and evaluation of novel α-l -fucosidase inhibitors, with X-ray crystallographic analysis using an α-l -fucosidase from Bacteroides thetaiotamicron helping to lay a foundation for future development of inhibitors for this important enzyme class.  相似文献   
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Somatostatin analogues are useful pharmaceuticals in peptide receptor radionuclide therapy. In previous studies, we analyzed a new bicyclic somatostatin analogue (BCS) in connection with Cu(II) ions. Two characteristic sites were present in the peptide chain: the receptor- and the metal-binding site. We have already shown that this ligand can form very stable imidazole complexes with the metal ion. In this work, our aim was to characterize the intramolecular interaction that occurs in the peptide molecule. Therefore, we analyzed the coordination abilities of two cyclic ligands, i.e., P1 only with the metal binding site and P2 with both sites, but without the disulfide bond. Furthermore, we used magnetic circular dichroism (MCD) spectroscopy to better understand the coordination process. We applied this method to analyze spectra of P1, P2, and BCS, which we have described previously. Additionally, we analyzed the MCD spectra of P3 ligand, which has only the receptor binding site in its structure. We have unequivocally shown that the presence of the Phe-Trp-Lys-Thr motif and the disulfide bond significantly increases the metal binding efficiency.  相似文献   
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This paper examines the possibilities of enhancing relationship management between public service broadcasters and their stakeholders by harnessing the potential of newest e-business technologies and concepts, such as: social media, digital and interactive TV, and mobile computing. In order to facilitate adoption of relationship management strategy, a framework for leveraging relationship management is proposed. Evaluation was performed within the e-business system of a public broadcaster. This empirical study explored the readiness and expected benefits of relationship management implementation. The research results have indicated that a public broadcaster could achieve a higher level of social responsibility, improve business sustainability, and empower communication and collaboration with all the stakeholders by using emerging technologies for relationship management activities.  相似文献   
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The research was conducted with the aim to investigate the possibility of Farinograph, Extensograph and Amylograph values prediction with linear and/or multiple Mixolab regression models. In total, 163 flour samples were divided based on Machalanobis distances into three sets: prediction, validation and external sample set. Determination coefficients ranged from 0.145 to 0.640 for linear regression models and from 0.279 to 0.739 for multiple regression models. Internal and external validation of developed regression models was conducted. Testing of developed models resulted in a high share of samples for which predicted values were out of the ranges of method official reproducibility and a high share of samples for which predicted values were out of the quality level range obtained by analytical measurement. It was concluded that it is impossible to develop applicable regression models for prediction of Farinograph, Extensograph and Amylograph parameters on the basis of Mixolab values from standard protocol.  相似文献   
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