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61.
Elina K. Hämäläinen Carita Kiili Eija Räikkönen Miika Marttunen 《Journal of Computer Assisted Learning》2021,37(5):1409-1422
Previous evaluation studies have rarely used authentic online texts and investigated upper secondary school students' use of evaluation criteria and deep reasoning. The associations between internet-specific epistemic justifications for knowing and credibility evaluation of online texts are not yet fully understood among adolescents. This study investigated upper secondary school students' (N = 372) abilities to evaluate self-selected authentic online texts and the role of internet-specific epistemic justifications in students' evaluation performance when solving a health-related information problem. Students selected three texts with Google Custom Search Engine and evaluated their credibility. Students' evaluation performance across the three texts was determined according to the different aspects evaluated (author, venue, intentions, evidence and corroboration) and the depth of their evaluations. Students also filled in the Internet-Specific Epistemic Justifications (ISEJ) inventory previously validated with pre-service teachers. The results revealed considerable differences in students' abilities to evaluate online texts. Students' beliefs in justification by authority and justification by multiple sources positively predicted their evaluation performance similarly in both topics. The findings suggest that the ISEJ inventory is also valid for upper secondary school students. Students should be explicitly taught to evaluate different credibility aspects and scaffolded to deeply engage with online information. 相似文献
62.
María Daniela Juárez Cibele Cristina Osawa María Elina Acuña Norma Sammán Lireny Aparecida Guaraldo Gonçalves 《Food Control》2011,22(12):1920-1927
This paper aims to study discontinuous deep frying of potatoes, milanesas (breaded bovine Semimembranosus muscle) and churros (flour, water, milk, lemon and salt) in soybean oil, sunflower oil and partially hydrogenated fats, monitored by conventional and unconventional methods. With the exception of partially hydrogenated fat after 80.5 h of deep-frying churros, all the oils exceeded 25% of total polar compounds (TPC) and the content of polymeric and dimerized triacylglycerols were higher than 10%, prevailing thermal alterations. For none of the samples the percentage of free fatty acids exceeded 2% of oleic acid. The losses of tocopherols during frying reached 76.0%. Little significant alterations occurred in the fatty acids composition, iodine index calculated, saponification index and formation of trans isomers after frying. The rapid tests used to determine TPC, malondialdehyde and alkenals have proved to be viable alternatives to monitor the quality of frying oils. 相似文献
63.
65.
Moisture-enhancing and marinating of meats are commonly used by the meat industry to add value to raw, retail products. Recently in Finland, certain value-added beef steak products have proven to be unusually susceptible to microbial spoilage leading to untoward quality deteriorations during producer-defined shelf-life. This study was conducted to evaluate the role of lactic acid bacteria (LAB) in the premature spoilage of value-added beef packaged under high-oxygen modified atmospheres. Spoilage was characterised by green discolouration and a buttery off-odour. The predominant LAB in eight packages of spoiled, marinated or moisture-enhanced beef steaks were identified by reference to a 16 and 23S rRNA gene restriction fragment length polymorphism pattern (ribotype) database. Leuconostoc gasicomitatum, Leuconostoc gelidum, Lactobacillus algidus, Lactobacillus sakei and Carnobacterium divergens were found to predominate in the LAB populations at numbers above 10(8) CFU/g. Inoculation of moisture-enhanced steaks with LAB strains and strain mixtures originating from the spoiled products demonstrated the spoilage potential of L. gasicomitatum and L. gelidum isolates. These two species produced green surface discolouration and buttery off-odours similar to these found in the spoiled, commercial products. 相似文献
66.
Rönkä E Malinen E Saarela M Rinta-Koski M Aarnikunnas J Palva A 《International journal of food microbiology》2003,83(1):63-74
Two Lactobacillus brevis strains ATCC 8287 and ATCC 14869(T), were evaluated for their applicability as putative probiotics in dairy products. The strains expressed good in vitro adherence to human Caco-2 and Intestine 407 cells and tolerated well low pH, bile acids and pancreatic fluid under in vitro conditions. In antimicrobial activity assays, strain ATCC 8287 showed inhibitory properties toward selected potential harmful microorganisms, particularly against Bacillus cereus. Both L. brevis strains were resistant to vancomycin, which is typical for the genus Lactobacillus. The L. brevis strains were not able to acidify milk to yoghurt but were suitable as supplement strains in yoghurts. This was shown by producing a set of yoghurt products and analysing their rheological and sensory properties during a cold storage period of 28 days. Survival of the strains through human intestine was examined in 1-week feeding trials. Despite its human origin, L. brevis ATCC 14869(T) could not survive through the gastrointestinal (GI) tract, whereas L. brevis ATCC 8287 was detected in the faecal samples taken during and immediately after ingestion of the strain. In conclusion, L. brevis ATCC 8287 is a promising candidate as a probiotic supplement in dairy products. 相似文献
67.
Narr Katherine L.; Green Michael F.; Capetillo-Cunliffe Linda; Toga Arthur W.; Zaidel Eran 《Canadian Metallurgical Quarterly》2003,112(4):623
Reports of left-hemisphere dysfunction and abnormal interhemispheric transfer in schizophrenia are mixed. The authors used a unified paradigm, the lateralized lexical decision task, to assess hemispheric specialization in word recognition, hemispheric error monitoring, and interhemispheric transfer in male, right-handed participants with schizophrenia (n=34) compared with controls (n=20). Overall, performance and error monitoring were worse in patients. However, patients like controls showed left-hemisphere superiority for lexical processing and right-hemisphere superiority for error monitoring. Only patients showed selective-interhemispheric lexicality priming for accuracy, in which performance improved when the lexical status of target and distractor stimuli presented to each hemifield was congruent. Results suggest that schizophrenia is associated with impaired monitoring and with increased interhemispheric automatic information transfer rather than with changed hemispheric specialization for language or error monitoring. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
69.
Current implementation of IS-95 based systems is performance limited due to the use of a “conventional” detection scheme,
which is susceptive to inter-user interference. We focus on the uplink, and try to examine the performance enhancement achieved
by a suboptimal linear multiuser MMSE pre-filter, applied in front of the “standard” detection mechanism. We demonstrate the
limitations of this relatively simple approach, and the constellations in which it may show improved performance.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
70.
Elina Buitrago Fredrik Tinnis Hans Adolfsson 《Advanced Synthesis \u0026amp; Catalysis》2012,354(1):217-222
Aromatic aldehydes, along with aryl alkyl, heteroaryl alkyl, and dialkyl ketones were efficiently reduced to their corresponding primary and secondary alcohols, respectively, in high yields, using the commercially available and inexpensive polymeric silane, polymethylhydrosiloxane (PMHS), as reducing agent. The reaction is catalyzed by in situ generated iron complexes containing hydroxyethyl‐functionalized NHC ligands. Turnover frequencies up to 600 h−1 were obtained. 相似文献