ABSTRACT
BACKGROUND: Previous research in the field of content and language integrated learning (CLIL) has not yet comprehensively investigated the interaction between learners' expertise and the instructional effectiveness. AIMS: Taking cognitive load theory as the theoretical framework, a study was conducted to investigate the expertise reversal effect on learning English and mathematics simultaneously: whether an integrated approach (i.e. learning both English and mathematics simultaneously) could facilitate the acquisition of mathematic skills and English linguistic skills as a foreign language more effectively and efficiently than a separated learning approach (i.e. learning Mathematics and English separately). MATERIALS: The materials for the integrated learning approach were in English-only, and the materials for the separated learning approach were in English-and-Chinese. Both sets of materials were given as reading content for teaching mathematic skills and English as a foreign language. METHODS: The study adopted a 2 (language expertise: low vs. high) × 2 (instruction: integrated vs. separated) between-subject factorial design with instructional approaches and learners' expertise in English as independent variables, the learning performance in Mathematics and English with the cognitive load ratings as the dependent variables. Sixty-five Year-10 students with lower expertise in English and 56 Year-2 college students with higher expertise in English in China were recruited and allocated to two instructional conditions respectively. RESULTS: An expertise reversal effect was confirmed: the English and mathematics integrated learning approach was more effective for higher expertise learners while the English and mathematics separated learning condition was more beneficial for lower expertise learners.
Subject(s)
Language , Learning , Humans , Cognition , Linguistics , StudentsABSTRACT
Learning to write in a foreign language is a complex cognitive process. The process-genre approach is a common instructional practice adopted by language teachers to develop learners' writing abilities. However, the interacting elements of procedural knowledge, linguistic knowledge, and generic knowledge in this approach may exceed the capacity of an individual learner's working memory, thus actually hindering the acquisition of writing skills. According to the collective working memory effect, it was hypothesized that teaching writing skills of English as a foreign language by adopting a process-genre approach in collaborative conditions could lead to better writing performance, lower cognitive load, and higher instructional efficiency. The reported experiment compared learning writing skills of English as a foreign language in individual and collaborative instructional conditions from a cognitive load perspective, a rarely adopted approach in this field. The results indicated that the collaborative instructional condition was more effective and efficient than the individual instructional condition in improving the quality of written products as well as in optimizing the cognitive (working memory) load experienced by the learners. Measures of cognitive load were used to support the cognitive load theory's interpretation of the results, which is the unique contribution of this research study to the field.
ABSTRACT
In this work, a new and simple method was developed for the synthesis of uncovered and high-selectivity spiramycin-based molecularly imprinted microspheres (SP-MIMs) by Pickering emulsion polymerization using spiramycin as templates. And surprisingly the solid particles were absent on the surface of imprinted microspheres, which can be ascribed to the Ganoderma lucidum spores (GLS): they were firstly selected to be the stabilizers for the Pickering emulsion in this new strategy. Through a series of adsorption experiments, the uncovered SP-MIMs were proven to possess more excellent selective recognition and removal ability for template SP in aqueous solution. And SP-MIMs could be reused for many times without significant loss of adsorption capacity, indicating the satisfactory regeneration performance. Therefore, SP-MIMs can be employed as a promising adsorbent for the selective removal of SP from aqueous media, and this strategy will contribute to overcoming the shortcomings of stabilizer particles on the surface of the as-prepared imprinting microspheres, because these solid particles lack the special selective recognition activity of template molecules, and may disturb the adsorption effect of imprinting microspheres.
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In this paper, we introduced Raman spectroscopy techniques that were based on the traditional Fe3+ determination method with phenanthroline as a probe. Interestingly, surface-enhanced Raman spectroscopy (SERS)-based approach exhibited excellent sensitivities to phenanthroline. Different detection mechanisms were observed for the RR and SERS techniques, in which the RR intensity increased with increasing Fe3+ concentration due to the observation of the RR effect of the phenanthroline-Fe2+ complex, whereas the SERS intensity increased with decreasing Fe3+ concentration due to the observation of the SERS effect of the uncomplexed phenanthroline. More importantly, the determination sensitivity was substantially improved in the presence of a SERS-active substrate, giving a detection limit as low as 0.001µg/mL, which is 20 times lower than the limit of the UV-vis and RR methods. Furthermore, the proposed SERS method was free from other ions interference and can be used quality and sensitivity for the determination of the city tap water.
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In this work, we designed a process to assemble gold nanoparticles onto a three-dimensional (3D) polymer surface, which can then be monitored using surface-enhanced Raman scattering (SERS). This work is the first demonstration of the assembly of gold nanoparticles on a filter film and in situ measurement with Raman spectroscopy. Herein, a polyhexamethylene adipamide (Nylon66) film embedded in the organic filter film was used as a template to fabricate a tunable SERS-active substrate. A "hotspot"-rich gold-nanoparticle-decorated polymer substrate for SERS was prepared; this substrate exhibited high sensitivity in trace detection of targets. The study was conducted using 4-mercaptobenzoic acid as a probe molecule with the aim of comparing the scattering efficiency and the homogeneity of the Raman signal on selected substrates. In addition, we used the gold-decorated polymer film to detect a biotin-avidin complex. The most powerful advantage of the proposed microanalytical device is the in situ SERS application. The 3D nanoporous structures described in this work hold strong potential for use in various applications such as environmental monitoring and biomolecule detection.
ABSTRACT
In this study, a new method for the quantitative evaluation of proteins is developed using competitive resonance Raman spectroscopy. A chelation reaction between bathocuproine disulfonate (BCS) and Cu(+) which is reduced by proteins in an alkaline environment, is utilized to create a BCS-Cu(+) complex that has strong resonance Raman activity. As a result, the method presented here enables protein detection over a much wider concentration range than conventional methods. Furthermore, the resonance Raman-based method can provide an improved lower limit of detection (500 pg/mL) compared to that obtained by colorimetric and ultraviolet- (UV-) based methods. Additionally, protein-to-protein variation can be determined using a standard curve created from known concentrations of bovine serum albumin (BSA), and excellent protein recovery is observed. More importantly, the proposed method was employing to the real sample (fetal bovine serum [FBS]). Based on the calibration curve from this method, it is extremely accurate for the determination of total protein concentrations in FBS. Results of this study demonstrate that the proposed method provides a novel and highly sensitive protocol for reagent-based protein assays.