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Peer feedback is a frequent feature of second language (L2) writing instruction. However, whether it is facilitative of L2 writing development is controversial. This meta-analysis aggregates the quantitative results of 26 empirical studies to (1) provide an accurate estimate of peer feedback's effectiveness in improving L2 writing, (2) compare its effects with those of other sources of feedback, and (3) identify factors moderating its effectiveness. Results revealed that peer feedback has a significant positive overall effect on students' writing: d = 0.73, 95% CI: 0.54-0.92. No significant differences were found between the effects of peer feedback, teacher feedback, and self-revisions; however, this finding is tentative given the small number of primary studies comparing peer feedback and feedback from other sources. Moderator analyses revealed larger effect sizes when students had more time to write and when treatments were longer. The analyses further showed that peer feedback had greater effects on revisions than new compositions and that peer feedback was more effective for content than language (lexis and grammar). Based on the findings and methodological features of the primary research, recommendations for further research are proposed so that firmer conclusions may be obtained in future meta-analyses.

This article reports on a study exploring the differential effects of immediate and delayed corrective feedback (CF) on the acquisition of the English past tense. One hundred and forty-five seventh-grade EFL learners were assigned to four groups: Immediate CF, Delayed CF, Task Only, and Control. Each experimental group performed six focused communicative tasks, two each in three treatment sessions, eliciting the use of the English past tense. The Immediate CF group received feedback on their erroneous use of the target structure in the first session, the Delayed CF group received feedback in the final session, and the Task Only group performed the communicative tasks without receiving any feedback. The Control group only took the achievement tests. The effects of the feedback treatments were measured through an untimed grammaticality judgment test and an elicited imitation test. Mixed-effects analyses examining the influence of both fixed and random factors demonstrated that immediate CF was more facilitative of L2 development than delayed CF. The results suggest the importance of addressing linguistic errors before they are proceduralized in the interlanguage.

This article discusses the conceptualization, measurement, and validity of a recently emerged construct in the field of second language acquisition (SLA)--implicit language aptitude (alternatively "implicit aptitude"). Implicit aptitude is a set of cognitive abilities that enable learners to make unconscious computations of the distributional and transitional probabilities of linguistic input. Implicit aptitude is key to an accurate understanding of the cognitive foundation of language learning and contributes significantly to the advancement of SLA theory and pedagogy. The article starts by clarifying the concept and components of implicit aptitude, elaborating its role in SLA theories, identifying its attributes, and discussing its measurement. It then synthesizes the empirical evidence on its divergent, convergent, and predictive validity, which refers to whether it is distinct or separable from explicit aptitude, whether measures of implicit aptitude are correlated, and whether it is predictive of learning outcomes, respectively. Next, the article provides an overview of the seven empirical studies included in this special issue that examined implicit aptitude from various perspectives. The article concludes by identifying future directions.

This study examines the associations between implicit and explicit language aptitude and the effects of the timing of corrective feedback (CF). A total of 112 seventh-grade EFL learners were assigned to three groups: Immediate CF, Delayed CF, and Task Only. The three groups underwent three treatment sessions during which they performed six focused communicative tasks eliciting the use of the English past tense. The Immediate and Delayed CF groups received CF treatments in the first and final sessions, respectively, and the Task Only group performed the communicative tasks without receiving any feedback. Treatment effects were measured through an untimed grammaticality judgment test and an elicited imitation test. Implicit language aptitude was operationalized as procedural memory and explicit language aptitude as working memory and declarative memory. Multiple regression analysis showed that procedural memory was significantly predictive of the effectiveness of Immediate CF, declarative memory was significantly associated with Delayed CF and Task Only, and working memory was a significant predictor of Immediate CF and Delayed CF. The results were interpreted by consulting the methodological features of the treatments and the mechanisms of the three cognitive abilities.

This study investigates the validity of syntactic priming as a measure of implicit language aptitude. Syntactic priming refers to the tendency to reproduce a linguistic structure due to a previous exposure to the structure. The validity of the construct was verified by collating evidence for divergent validity--whether it is dissociable from explicit aptitude; convergent validity--whether it is correlated with other measures of implicit aptitude; and predictive validity--whether it is predictive of learning attainment. One hundred sixty-six university EFL learners completed three tests of implicit aptitude: syntactic priming, sequence learning, and LLAMA_D; three tests of explicit aptitude: LLAMA_B, _E, and _F; and three tests of L2 proficiency: untimed grammaticality judgment, metalinguistic knowledge, and elicited imitation. The results showed that syntactic priming was dissociable from explicit aptitude, but it failed to converge with the other measures of implicit aptitude, and it also failed to predict L2 proficiency. The results also showed that priming was negatively correlated with sequence learning and that sequence learning was a negative predictor of learners' metalinguistic knowledge. On the other hand, the construct validity of explicit aptitude was strong. The results suggest the multidimensionality of implicit aptitude and the need for more research into the construct validity of syntactic priming as a cognitive ability for implicit learning.

Instructional context plays a crucial role in the learning of a second/foreign language. The present study compared the occurrence of corrective feedback (CF) and learner uptake across two instructional contexts at the tertiary level: English as a second language (ESL) in the US and English as a foreign language (EFL) in China. Analysis of 36 h of observation data showed that (1) recast was the most preferred feedback type in both settings, but with a much higher percentage in the EFL lessons than in the ESL lessons; (2) the distribution of CF was similar in terms of emphasis but was significantly different in terms of linguistic focus; and (3) the overall frequencies of uptake and repair were close between the two settings, but the rates of uptake and repair following explicit correction were significantly higher in the EFL lessons than in the ESL lessons. These findings suggest that although teacher-student interactions across ESL and EFL settings demonstrate a common trend, CF and uptake are not context-free.

Efforts have been made to find a better therapeutic approach with fewer side effects in treating chronic obstructive pulmonary disease (COPD). This study investigated the effect of Buyuan decoction (BYD) on autophagy in COPD rats. An experimental model with Sprague-Dawley rats was established by lipopolysaccharide (LPS) injection and cigarette smoke exposure. Rats were randomly allocated into blank control (normal control), experimental model, low-dose BYD (8.0 g/kg/day), medium-dose BYD (16.0 g/kg/day), high-dose BYD (32.0 g/kg/day) and 3-MA (methyladenine) groups (6 rats/group). Cell and tissue morphology were observed using hematoxylin and eosin staining. Autophagic vesicles were examined with a transmission electron microscope. Protein expression of LC3-II/I, BNIP- 1, ATG7, p62, PI3K and p-PI3K in lung tissue was detected by Western blotting. Compared with the experimental model group, the inflammatory infiltrate in lung tissue was reduced, the nuclei of the pulmonary epithelial cells were restored to normal, and the expression of LC3, BNIP1, ATG7 and p-PI3K was significantly downregulated, while p62 expression was significantly upregulated after treatment with the BYD. The effect was most significant in the low-dose BYD group (P

This study examines the joint effects of task repetition and corrective feedback on EFL learners’ writing accuracy. Two types of task repetition were investigated: identical repetition where learners repeated the same task, and procedural repetition where learners performed tasks with different content following the same procedure. Under each repetition condition, learners received direct correction or metalinguistic feedback on their erroneous use of three linguistic structures: the past tense, articles, and prepositions. 80 Korean university EFL learners were randomly assigned to four groups: identical repetition + direct feedback, identical repetition + metalinguistic feedback, procedural repetition + direct feedback, and procedural repetition + metalinguistic feedback, and received one of the four instructional treatments. The results showed that (1) procedural repetition was superior to identical repetition in enhancing learners’ writing accuracy regardless of whether direct feedback or metalinguistic feedback was provided, and (2) there were no significant differences between the two types of feedback despite a trend toward a greater effect for metalinguistic feedback for the past tense and a greater effect for direct correction for articles and prepositions. The results demonstrate the advantage of procedural repetition over identical repetition in enhancing the effects of corrective feedback in L2 writing. [ABSTRACT FROM AUTHOR]

In finite water depths, the effects of high winds and linear shear flow (LSF), encompassing both uniform flow and constant vorticity shear flow on freak wave generation are explored. A nonlinear Schrödinger equation, adjusted for high wind and LSF conditions, is derived using potential flow theory and the multiscale method. This equation accounts for the modulational instability (MI) of water waves and the evolution of freak wave amplitudes. MI analysis reveals that for waves to maintain MI, high tail winds (moving in the same direction as the wave) require less vorticity and deeper water, while adverse winds (moving in the opposite direction) necessitate more vorticity and shallower water depths compared to conditions without wind. Uniform up-flows (down-flows), positive (negative) vorticity, and high tail (adverse) winds, which inhibit (promote) wave propagation, increase (decrease) the MI growth rate and amplify (diminish) freak wave heights. It is through this MI that the generation of freak waves is either promoted or inhibited. [ABSTRACT FROM AUTHOR]

This study provides a systematic review of the methodological features of meta-analyses in second language learning. The synthesis aims to inform how meta-analyses in L2 learning have been conducted, evaluate whether methodological decisions are aligned with norms and standards, identify issues, and suggest solutions based on expert advice, statistical guides, and best practices. A total of 120 meta-analyses were retrieved and coded for key features related to bibliographic and demographic characteristics, search and selection, publication bias, quality control, data coding, data analysis, and effect size interpretation. The synthesis showed that 98 meta-analyses examined the effectiveness of instructional treatments, 21 investigated correlations, and one explored the occurrence of events. These meta-analyses included an average of 37 primary studies (range = 9–302). Common selection criteria the meta-analyses applied included publication type, availability of data for effect size calculation, learner traits, learners' target languages, publication dates, publication language, independent variables, and dependent variables. Major strategies used to detect publication bias included creating a funnel plot, using trim-and-fill analysis, and calculating a fail-safe N. Typical moderators examined in the meta-analyses related to research context, treatment features, sample characteristics, and outcome measures. The synthesis also identified a number of issues, including failure to report key features such as model selection (fixed- vs. random-effects model), effect size weighting, and so on; conducting moderator analysis based on very small cell sizes (e.g., only one study in a subgroup); lack of justification for certain methodological decisions such as using d instead of g, using confidence intervals rather than Q-tests to identify significant moderators; lack of quality control; and confounding study-based and synthesis-based moderators. We offer advice on identified issues and call for more transparency of reporting. [ABSTRACT FROM AUTHOR]

This article calls for replication of two studies (Li, Zhu & Ellis 2016; Arroyo & Yilmaz 2018) that examine the timing of corrective feedback, which refers to whether errors should be corrected during a communicative task (immediate feedback) or after the task is completed (delayed feedback). The article starts with a rationale for replicating the two studies: they address a topic of significance to theorists, researchers, and practitioners; they are conducted with rigorous methods; they represent classroom and laboratory research respectively; they both show an advantage for immediate feedback. It proceeds to contextualize the subsequent discussion of replication strategies by (1) elaborating the theoretical claims and pedagogical positions on the influence of the timing of corrective feedback on learning outcomes and task performance, and (2) summarizing the findings of the research on the effectiveness of corrective feedback. After some background information is provided, a detailed discussion is given for each of the two studies, including a summary of the methods and findings, followed by recommendations about how to replicate.

In arbitrary water depths, the influence of uniform flow, which includes transverse and longitudinal flows, on the generation of three-dimensional (3D) freak waves is examined. A modified Davey–Stewartson equation is derived using potential flow theory and the multiscale method. This equation describes the evolution of 3D freak wave amplitude under the influence of uniform flow. The relationship between two-dimensional (2D) modulational instability (MI) and the generation of 3D freak waves, as represented by the modified 3D Peregrine Breather solution, is explored. The characteristics of 2D MI depend on the orientation of the longitudinal and transverse perturbations. In shallow waters, the generation of freak waves by MI is challenging due to the minimal orientation difference, and longitudinal flows hardly affect the occurrence of MI. Variations in relative water depth can contribute to forming shallow-water freak waves. In finite-depth waters, oblique modulation leads to MI, whereas in deep and infinite-depth waters, longitudinal modulation gains significance. In environments of finite-depth, deep, and infinite-depth waters, the divergence (convergence) effect of longitudinal favorable (adverse) currents reduces (increases) the MI growth rate and suppresses (facilitates) freak wave generation. [ABSTRACT FROM AUTHOR]

A systematic and comprehensive comparison of the five commonly used earth radii in geodesy and cartography is carried out, and the differences between the most common points of the earth radii, their corresponding maximum values, and the latitudes of equal points between them are derived with the help of computer algebraic systems. The symbolic expressions are expressed as a power series of the first eccentricity. Taking the CGCS2000 ellipsoid as an example, the differences between the commonly used earth radii are clarified to numerical values. The results show that the difference between the commonly used earth radii has a maximum at 90 degrees and a minimum at 0 degree. The difference between the average radius of curvature and the rectifying sphere radius is the biggest, and the difference between the average radius of curvature and the average sphere radius is the smallest. These results can provide a theoretical basis for corresponding research in the geosciences, space science, navigation and positioning.

This study investigated the comparative effects of strategic and unpressured within-task planning on second language (L2) Chinese oral production and the role of working memory in mediating the effects of the two types of planning. Twenty-nine L2 Chinese learners at a large New Zealand university performed a narrative task after watching a 6-minute silent movie, followed by an operation span test gauging the learners' working memory capacity. The results revealed that (1) strategic planning enhanced fluency and unpressured within-task planning led to greater accuracy and syntactic complexity, (2) strategic planning facilitated the production of a syntactically transparent structure, while unpressured within-task planning showed an advantage for opaque, complex structures, and (3) working memory was drawn upon in unpressured within-task planning, but barely so in strategic planning. The data show that strategic planning benefits the Conceptualizer while unpressured within-task planning favors the Formulator. The data also suggest that the role of cognitive abilities in task performance is contingent upon the processing demands of different task conditions.