PISA

PISA
  • 文章类型: Journal Article
    目前的研究采用潜在的概况分析,以PISA2018数据为基础,考察了中国学生阅读元认知策略的应用模式。随后,它探讨了学生数学学习效率和表现的差异。结果表明:(1)确定了六种类型的阅读元认知策略应用模式:“新手-冷漠,\"\"退伍军人-平均水平,\"\"新手-低评价,\"\"资深技术,\"\"新手-混合,\"和\"新手-任意。(2)影响阅读元认知策略应用模式分类的主要因素是性别,家庭经济,社会,文化地位(ESCS)。(3)数学学习时间可以积极预测整体成绩,但是,“老练”和“新手混合”学生的数学学习时间与他们的数学成绩没有显着相关性。研究结果表明,教育工作者不应盲目增加学生的数学学习时间,而应根据他们对阅读元认知策略的掌握方式提供适当的指导,以提高数学学习效率和表现。
    The current study employed latent profile analysis to examine the application patterns of students\' reading metacognitive strategies using PISA 2018 data in China. Subsequently, it explored the differences in students\' mathematics learning efficiency and performance. The results revealed that: (1) Six types of reading metacognitive strategies application patterns were identified: \"Novice - indifferent,\" \"Veteran - average,\" \"Novice - low evaluating,\" \"Veteran - skilled,\" \"Novice - mixed,\" and \"Novice - arbitrary.\" (2) The primary factors that affect the classification of reading metacognitive strategies application patterns were gender, and family economic, social, and cultural statuses (ESCS). (3) Mathematics learning time could positively predict performance overall, but the mathematics learning time of \"Veteran - skilled\" and \"Novice - mixed\" students had no significant correlation with their mathematics performance. The findings suggests that educators should not blindly increase students\' mathematics learning time but instead provide appropriate guidance based on their mastery patterns of reading metacognitive strategies to enhance mathematics learning efficiency and performance.
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  • 文章类型: Journal Article
    诊断分类模型(DCMs)在教育和心理测量中得到了广泛的应用,尤其是形成性评估。在最近的文献中已经研究了存在testlet的DCM。基于测试的DCM的统计建模和分析的关键因素是两个潜在结构的叠加,属性配置文件和testlet效果。本文扩展了标准测试DINA(T-DINA)模型,以适应两种潜在结构之间的潜在相关性。研究了模型的可辨识性,并提出了一组充分条件。作为副产品,还建立了标准T-DINA的可识别性。所提出的模型应用于2015年国际学生评估计划的数据集。与DINA和T-DINA进行比较,表明在拟合优度方面有了实质性的改善。进行仿真以评估新方法在各种设置下的性能。
    Diagnostic classification models (DCMs) have seen wide applications in educational and psychological measurement, especially in formative assessment. DCMs in the presence of testlets have been studied in recent literature. A key ingredient in the statistical modeling and analysis of testlet-based DCMs is the superposition of two latent structures, the attribute profile and the testlet effect. This paper extends the standard testlet DINA (T-DINA) model to accommodate the potential correlation between the two latent structures. Model identifiability is studied and a set of sufficient conditions are proposed. As a byproduct, the identifiability of the standard T-DINA is also established. The proposed model is applied to a dataset from the 2015 Programme for International Student Assessment. Comparisons are made with DINA and T-DINA, showing that there is substantial improvement in terms of the goodness of fit. Simulations are conducted to assess the performance of the new method under various settings.
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  • 文章类型: Journal Article
    用于光介导的可逆失活自由基聚合(photo-RDRP)的无金属有机光催化剂在聚合物的精确合成方面取得了越来越多的进步。然而,在开发基于高效和环境可持续的碳点(CD)的有机催化剂方面仍然存在挑战。在这里,制备了源自菲咯啉衍生物(Aphen)的N掺杂CD,作为不含金属的光催化剂,用于光诱导电子转移可逆加成-断裂链转移(PET-RAFT)聚合。菲咯啉结构的引入提高了CD的激发态寿命,并扩大了其内部结构的共轭长度,使光吸收达到绿光区,从而提高光催化活性。设计的CD在光聚合中表现出前所未有的光催化能力,即使在大体积反应(100mL)中,在绿光下具有高单体转化率和窄聚合物分散性(Mw/Mn<1.20)。光催化体系与许多单体的PET-RAFT聚合和高分子量聚丙烯酸酯(Mn>250.000)的生产相容,具有精确的时空控制。以上结果证实了CD作为光催化剂的潜力,这在光RDRP中使用的其他CD催化剂中还没有实现。此外,首次成功证明了使用CD作为光催化剂和荧光粉通过光引发聚合诱导自组装(Photo-PISA)技术构建的荧光聚合物纳米颗粒。
    Metal-free organic photocatalysts for photo-mediated reversible deactivation radical polymerization (photo-RDRP) are witnessed to make increasing advancement in the precise synthesis of polymers. However, challenges still exist in the development of high-efficiency and environmentally sustainable carbon dots (CDs)-based organocatalysts. Herein, N-doped CDs derived from phenanthroline derivative (Aphen) are prepared as metal-free photocatalysts for photoinduced electron transfer reversible addition-fragmentation chain transfer (PET-RAFT) polymerization. The introduction of phenanthroline structure enhances the excited state lifetime of CDs and expands the conjugated length of their internal structure to enable the light-absorption to reach green light region, thereby enhancing photocatalytic activity. The as-designed CDs exhibit unprecedented photocatalytic capacity in photopolymerization even in large-volume reaction (100 mL) with high monomer conversion and narrow polymer dispersity (Mw/Mn < 1.20) under green light. The photocatalytic system is compatible with PET-RAFT polymerization of numerous monomers and the production of high molecular weight polyacrylate (Mn >250 000) with exquisite spatiotemporal control. Above results confirm the potential of CDs as photocatalyst, which has not been achieved with other CDs catalysts used in photo-RDRP. In addition, the construction of fluorescent polymer nanoparticles using CDs as both photocatalyst and phosphor through photoinitiated polymerization-induced self-assembly (Photo-PISA) technology is successfully demonstrated for the first time.
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  • 文章类型: Journal Article
    基于计算机的评估提供了收集与解决问题过程相关的行为数据的新来源的机会,称为日志文件数据。为了理解可以从这些过程数据中发现的行为模式,许多研究都采用了聚类方法。与单模式聚类算法相比,这项研究利用了双聚类方法,允许同时对测试者和从日志文件中提取的特征进行分类。通过将双聚类算法应用于PISA2012CPS评估中的“票证”任务,我们评估了双聚类算法在从过程数据中识别和解释同质双聚类方面的潜力.与单模式聚类算法相比,双聚类方法可以发现在特征变量子集上同质的个体集群,持有承诺,获得对学生解决问题的行为模式的细粒度见解。实证结果表明,特定的特征子集在识别双色花序中起着至关重要的作用。此外,这项研究探索了双聚类在动作序列数据和时序数据上的利用,以及基于时间的特征的纳入增强了学生对分析背景下的动作序列和分数的理解。
    Computer-based assessments provide the opportunity to collect a new source of behavioral data related to the problem-solving process, known as log file data. To understand the behavioral patterns that can be uncovered from these process data, many studies have employed clustering methods. In contrast to one-mode clustering algorithms, this study utilized biclustering methods, enabling simultaneous classification of test takers and features extracted from log files. By applying the biclustering algorithms to the \"Ticket\" task in the PISA 2012 CPS assessment, we evaluated the potential of biclustering algorithms in identifying and interpreting homogeneous biclusters from the process data. Compared with one-mode clustering algorithms, the biclustering methods could uncover clusters of individuals who are homogeneous on a subset of feature variables, holding promise for gaining fine-grained insights into students\' problem-solving behavior patterns. Empirical results revealed that specific subsets of features played a crucial role in identifying biclusters. Additionally, the study explored the utilization of biclustering on both the action sequence data and timing data, and the inclusion of time-based features enhanced the understanding of students\' action sequences and scores in the context of the analysis.
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  • 文章类型: Journal Article
    背景:社会经济地位是影响学生动机和成就的最重要因素之一,但很少与成就目标有关。
    目的:本研究旨在调查掌握方法目标是否解释了SES与关键学习相关结果(中介)之间的联系,以及SES是否改变了掌握方法目标与这些结果之间的关系(适度)。
    方法:数据来自77个国家的21,322所学校的595,444名学生。
    方法:使用多级调节中介分析对数据进行分析。
    结果:我们发现了显著的中介和适度。在调解方面,掌握方法目标介导了家庭SES和学习相关结局之间的关联。然而,学校SES出现了不同的模式,因为高等SES学校的学生掌握方法目标较低。在适度方面,我们发现家庭SES加强了掌握法目标和学习相关结局之间的关联.然而,在较高的SES学校中,掌握方法目标和学习相关结局之间的关联较弱.
    结论:讨论了成就目标方法对成就动机的理论和实践意义。
    BACKGROUND: Socio-economic status is one of the most important factors shaping students\' motivation and achievement but has seldom been explored in relation to achievement goals.
    OBJECTIVE: This study aimed to investigate whether mastery-approach goals explain the link between SES and key learning-related outcomes (mediation) and whether SES modifies the relationship between mastery-approach goals and these outcomes (moderation).
    METHODS: Data came from 595,444 students nested in 21,322 schools across 77 countries.
    METHODS: Data were analysed using multilevel-moderated mediation analyses.
    RESULTS: We found significant mediation and moderation. In terms of mediation, mastery-approach goals mediated the association between family SES and learning-related outcomes. However, a different pattern emerged for school SES, as students in higher SES schools had lower mastery-approach goals. In terms of moderation, we found that family SES strengthened the association between mastery-approach goals and learning-related outcomes. However, the association between mastery-approach goals and learning-related outcomes was weaker in higher SES schools.
    CONCLUSIONS: Theoretical and practical implications for the achievement goal approach to achievement motivation are discussed.
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  • 文章类型: Journal Article
    具有蠕虫状形态的聚(单甲基丙烯酸甘油酯)-嵌段聚(甲基丙烯酸2-羟丙酯)(PGMA-PHPMA)是通过聚合诱导的自组装(PISA)在水溶液中的可逆加成-断裂链转移(RAFT)分散聚合的热响应性共聚物的典型例子。链转移剂(CTAs)是控制RAFT的关键组分,其结构决定了聚合物链的末端官能团。因此,通过CTA部分单官能化聚合物是有意义的,用于生物活性官能团缀合,并且同时保持共聚物的精确控制的形态和相关性质。在这项工作中,合成了一种新设计的CTA5-(2-(叔丁氧基羰基氨基)乙基氨基)-2-氰基-5-氧代戊烷-2-基苯甲酸酯(t-BocCPDB),并用于PGMA45-PHPMA120的RAFT聚合。随后,PGMA45-PHPMA120与伯胺的共聚物,马来酰亚胺,通过去保护和缀合反应合成还原的L-谷胱甘肽(三肽)单官能化末端。这些单官能化共聚物在水溶液(10%w/v)中保持蠕虫状形态和热响应性,正如透射电子显微镜(TEM)图像所证实的那样,以及在4°C至室温(〜20°C)之间的相变行为的观察,分别。总之,成功合成了一系列热响应性单官能化PGMA45-PHPMA120二嵌段共聚物蠕虫,有望提供潜在的生物医学应用,比如在聚合物疗法中,药物输送,和诊断。
    Poly(glycerol monomethacrylate)-block-poly(2-hydroxypropyl methacrylate) (PGMA-PHPMA) with worm-like morphology is a typical example of reversible addition-fragmentation chain transfer (RAFT) dispersion polymerized thermo-responsive copolymer via polymerization-induced self-assembly (PISA) in aqueous solution. Chain transfer agents (CTAs) are the key component in controlling RAFT, the structures of which determine the end functional groups of the polymer chain. It is therefore of interest to monofunctionalize the polymers via CTA moiety, for bioactive functionality conjugation and in the meantime maintain the precisely controlled morphology of the copolymers and the related property. In this work, a newly designed CTA 5-(2-(tert-butoxycarbonylamino) ethylamino)-2-cyano-5-oxopentan-2-yl benzodithioate (t-Boc CPDB) was synthesized and used for the RAFT polymerization of PGMA45-PHPMA120. Subsequently, PGMA45-PHPMA120 copolymers with primary amine, maleimide, and reduced L-glutathione (a tripeptide) monofunctionalized terminals were synthesized via deprotection and conjugation reactions. These monofunctionalized copolymers maintain worm-like morphology and thermo-responsive property in aqueous solution (10% w/v), as confirmed by the transmission electron microscopy (TEM) images, and the observation of the phase transition behavior in between 4 °C and room temperature (~20 °C), respectively. Summarily, a range of thermo-responsive monofunctionalized PGMA45-PHPMA120 diblock copolymer worms were successfully synthesized, which are expected to offer potential biomedical applications, such as in polymer therapeutics, drug delivery, and diagnostics.
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  • 文章类型: Journal Article
    聚合诱导自组装(PISA)将聚合和嵌段共聚物的原位自组装结合在一个系统中,已成为制备高浓度嵌段共聚物纳米颗粒的广泛使用的方法。聚合物在环境中的持久性对生态系统构成了巨大威胁,并代表了资源的重大浪费。迫切需要开发新的化学方法来合成可降解聚合物。为了满足这一需求,将降解性安装到PISA纳米粒子中至关重要。最近,可降解的PISA纳米颗粒已经通过将降解机制引入到壳形成或核形成嵌段中来合成。本文综述了PISA合成的可降解嵌段共聚物纳米粒子的研究进展,包括壳可降解,核心可降解和全降解纳米粒子。未来的发展将受益于具有新降解机制的聚合技术的扩展以及对PISA合成和降解研究的高通量方法的适应。
    Polymerization-induced self-assembly (PISA) combines polymerization and in situ self-assembly of block copolymers in one system and has become a widely used method to prepare block copolymer nanoparticles at high concentrations. The persistence of polymers in the environment poses a huge threat to the ecosystem and represents a significant waste of resources. There is an urgent need to develop novel chemical approaches to synthesize degradable polymers. To meet with this demand, it is crucial to install degradability into PISA nanoparticles. Most recently, degradable PISA nanoparticles have been synthesized by introducing degradation mechanisms into either shell-forming or core-forming blocks. This Minireview summarizes the development in degradable block copolymer nanoparticles synthesized by PISA, including shell-degradable, core-degradable, and all-degradable nanoparticles. Future development will benefit from expansion of polymerization techniques with new degradation mechanisms and adaptation of high-throughput approaches for both PISA syntheses and degradation studies.
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  • 文章类型: Journal Article
    由于单分散胶体粒子组装的响应光子晶体(RPC)在智能设备中的巨大应用,最近引起了人们的极大兴趣。它们的结构颜色可以由颗粒尺寸决定。然而,缺乏可靠的方法来调整原位尺寸限制了它们的发展。在这里,我们提出了一种有效的途径来解决这个问题,通过制造具有光触发可逆溶胀行为的球形聚合物颗粒,通过不含表面活性剂的可逆加成-断裂链转移(RAFT)乳液聚合诱导的自组装。合成了含有偶氮苯基团的两亲性大分子RAFT试剂,随后用于介导甲基丙烯酸甲酯的聚合。通过调节固体含量和其他参数获得均匀的亚微米球体。受益于偶氮苯部分的光异构化,因此,在替代的紫外/可见光照射下,颗粒尺寸膨胀和收缩。该策略将是乳液PISA的补充,尤其是有助于RPC材料的进步。
    Responsive photonic crystals (RPCs) assembled by monodisperse colloidal particles have attracted enormous interest recently due to their tremendous applications in smart devices. Their structural colors can be determined by particle sizes. However, the lack of a reliable way to tune the sizes in situ limits their development. Herein, we present an efficient route to solve this problem through the fabrication of spherical polymeric particles with light-triggered reversible swelling behavior via surfactant-free reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization-induced self-assembly (PISA). Amphiphilic macro-RAFT agents containing azobenzene groups were synthesized and subsequently employed to mediate the polymerization of methyl methacrylate. Uniform submicron spheres were obtained by modulating solid contents and other parameters. Benefiting from the photoisomerization of azobenzene moieties, the particle sizes expanded and contracted upon alternative ultraviolet/visible-light irradiation accordingly. This strategy will be a supplement to the emulsion PISA and especially give aid to the progress of the RPC materials.
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  • 文章类型: Journal Article
    由于21世纪教学和学习的挑战性,教育工作者必须在学校承担额外的角色,以满足学生的期望,父母,和社区。总的来说,研究集中于所有教师作为一个群体。2015年PISA评估和分析框架表明,本轮评估的重点是科学素养。因此,科学教师专业合作,教学自我效能感,教师工作满意度也是其衡量的重点。在这项研究中,来自香港的1039名科学教师参加了会议。通过文献综述分析,本研究的结论是:(a)教师专业合作和教学自我效能感对工作满意度有正向影响;(b)教师专业合作对教学自我效能感有正向影响,(c)教学自我效能感在教师专业合作和教师工作满意度中具有中介作用。开发了一个中介模型来检验这一假设。采用结构方程模型(SEM)对数据进行分析。研究结果证实了我们的假设。此外,我们使用多组SEM模式检验了模型的适用性,结果显示,专业合作对香港理科教师工作满意度的影响,中国没有性别差异。
    Due to the challenging nature of teaching and learning in the 21st century, educators must assume additional roles in schools to meet the expectations of students, parents, and communities. Studies in general have focused on all teachers as a group. The PISA 2015 assessment and analysis framework indicates that the focus of the current round of assessment is on science literacy. Therefore, science teacher professional collaboration, teaching self-efficacy, and teacher job satisfaction were also the focus of its measurement. In this study, 1039 science teachers from Hong Kong participated. Through literature review analysis, this study concluded that (a) teacher professional collaboration and teaching self-efficacy have a positive effect on job satisfaction; (b) teacher professional collaboration has a positive effect on teaching self-efficacy, and (c) teaching self-efficacy has a mediating role in teacher professional collaboration and teacher job satisfaction. A mediation model was developed to test this hypothesis. Data were analyzed using structural equation modeling (SEM). The results of the study confirmed our hypothesis. In addition, we examined the applicability of the model using multi-group SEM mode, and the results demonstrated that the effect of professional collaboration on job satisfaction among science teachers in Hong Kong, China did not differ by gender.
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  • 文章类型: Journal Article
    五种未描述的二氢类黄酮糖苷衍生物,即albvisosidesA-E,从Viscum专辑L.var的根和茎叶中分离出两种已知化合物。专辑。(欧洲槲寄生)。它们的结构由HRESIMS确定,1D和2DNMR,和ECD分析。在非常低的浓度(EC50:0.7nM)下,AlbvisosideB对HepG2细胞中的肝脂质积累表现出显著的抑制作用。使用蛋白质组积分溶解度改变测定,阐明了albvisosideB的直接靶标或下游效应物。因此,基于配体诱导的蛋白质热稳定性改变鉴定了97种蛋白质。生物信息学分析显示,叶黄素B主要通过调节硒氨基酸代谢信号通路来改善油酸诱导的脂质积累。
    Five undescribed dihydroflavonoid glycoside derivatives, namely albvisosides A‒E, together with two known compounds were isolated from the roots and stem leaves of Viscum album L. var. album. (European mistletoe). Their structures were determined by HRESIMS, 1D and 2D NMR, and ECD analysis. Albvisoside B exhibits significant inhibitory effect on hepatic lipid accumulation in HepG2 cells at very low concentrations (EC50: 0.7 nM). Using proteome integral solubility alteration assay, the direct targets or downstream effectors of albvisoside B were elucidated. As a result, 97 proteins were identified based on ligand-induced alterations in the protein thermal stability. Bioinformatics analysis indicated that albvisoside B primarily ameliorated oleic acid-induced lipid accumulation by regulating the selenoamino acids metabolism signaling pathway. RPL3, ADAM17, and RPL14 were likely to be involved in mediating the lipid-lowering effect of albvisoside B.
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