Instructed SLA and Task-Based Language Teaching

Although second language acquisition (SLA) and language teaching are two distinct fields, an increasing number of classroom-based SLA research on the effectiveness of different types of instruction, such as focus on forms, focus on meaning, and focus on form (see Norris & Ortega, 2000 for a review), corrective feedback (e.g., Lyster & Ranta, 1997), input enhancement (e.g., White, 1998), etc., has brought about a burgeoning subfield of SLA known as Instructed SLA (ISLA). ISLA, which is often pitted against naturalistic SLA, “occurs in formal settings where language is intentionally taught and intentionally learned – within a limited amount of time” (Spada, 2015, p. 71). Given ISLA’s immediate and potential relevance to second language (L2) pedagogy, Long (2014) made the first attempt to formulate a cognitive-interactionist theory of ISLA. In what follows, this theory will first be presented and then discussed in relation to its significance to and implications for task-based language teaching (TBLT) and syllabus design

Paired and Group Oral Assessment

The assessment of second language (L2) speaking has long been an important yet challenging area of research in language testing. L2 testers are often concerned with designing authentic speaking tasks that resemble real-life speaking activities so that score interpretations are generalizable to non-test contexts. The conversational nature of speaking skills has promoted the widespread integration of more authentic and interactive assessment tasks, such as paired or group orals. Such direct test formats typically involve candidates interacting together to perform a task while one or more examiners observe their performances and rate their language proficiency (Van Moere, 2013, p. 1)

Domains and Directions in the Development of TBLT

If one has to use a catchy word to capture the connection between the field of Second Language Acquisition (SLA) and Language Teaching (LT), the word “task” would be most likely to jump to mind. Since its initial proposals in the late 1980s, the concept has now blossomed into a distinct field of research, Task-Based Language Teaching (TBLT), which is often deemed to be a researched pedagogy that bridges a gap between SLA research and LT. Much of the development in TBLT is due to scholarly presentations and publications, particularly those by Long (1985, 2015), Skehan (1998), and Robinson (2001, 2011), among many others. The book Domains and Directions in the Development of TBLT is a comprehensive collection of selected plenary speeches delivered at biennial international conferences on TBLT from 2005 to 2013. Martin Bygate, editor of the book, introduces the book by highlighting the pivotal role of tasks and the research and educational relevance of TBLT, echoed throughout the entire book

Unpacking Reading Text Complexity: A Dynamic Language and Content Approach

Reading texts may serve as a vital source of informational content and language knowledge for English language learners, which is known as the dual relevance of second language reading (Han & D’Angelo, 2009). Text complexity, however, mediates the two, determining to a great extent whether the dual outcome is attainable. Drawing on Complex Dynamic System Theory (CDST, de Bot, 2017), the present study conceives text complexity as residing primarily in the dynamic interplay between language and content complexity and their respective subsystems. To examine the viability of this conceptualization, this study analyzed language complexity and content complexity of authentic science texts sampled from high school and college textbooks on four different subjects. Results show that college texts in general exhibited greater language and content complexity than high school texts, especially in terms of sentence length and the use of complex nominals. Aside from this emerging pattern, variability characterized the magnitude of difference in complexity and the manner in which the texts differed. Overall, the findings from this study attest to the mutually reciprocal dynamics of language complexity and content complexity embedded within authentic texts

Criterions, Prediction and Prevention of Loess Liquefaction

Although loess liquefaction is not very common during earthquakes in Northwest of China, it is disastrous if it happens. Both study and valid evidence from Haiyuan 8.5 Earthquake in 1920 and Tajikistan 5.9 Earthquake in 1989 have proved that loess liquefaction could be very disastrous under certain conditions. In this paper, the criterions of loess liquefaction are discussed to show that unlike typical liquefaction of sand, loess which falls into the category of both silt clay and clayey silt has unique characteristics during liquefaction test. To predict liquefaction of loess, a simple method based on laboratory test and field evidences using GIS is proposed. The prediction results and corresponding measure have been adopted in Seismic Design Code for Buildings in Lanzhou Urban Area. Finally, recent approach of treatment of loess with chemicals methods is developed, which may have some application implication as an simple and feasible treatment method against liquefaction of loess

Looking Back, Looking Ahead: An Interview with Professor ZhaoHong Han

On April 8, 2021, we had the great pleasure of speaking over Zoom with Professor ZhaoHong Han, the founding editor of SALT, which was originally called Working Papers in TESOL and Applied Linguistics. In celebration of the journal’s 20thanniversary, we discussed the motivation and vision behind establishing a web journal, future directions, essential qualities of an outstanding original research article, and advice for early career scholars and graduate students who are starting out to get their work published in journals

In Situ TEM Study of the Degradation of PbSe Nanocrystals in Air

PbSe nanocrystals have attracted widespread attention due to a variety of potential applications. However, the practical utility of these nanocrystals has been hindered by their poor air stability, which induces undesired changes in the optical and electronic properties. An understanding of the degradation of PbSe nanocrystals when they are exposed to air is critical for improving the stability and enhancing their applications. Here, we use in situ transmission electron microscopy (TEM) with an environmental cell connected to air to study PbSe nanocrystal degradation triggered by air exposure. We have also conducted a series of complementary studies, including in situ environmental TEM study of PbSe nanocrystals exposed to pure oxygen and PbSe nanocrystals in H2O using a liquid cell, and ex situ experiments, such as O2 plasma treatment and thermal heating of PbSe nanocrystals under different air exposure. Our in situ observations reveal that when PbSe nanocrystals are exposed to air (or oxygen) under electron beam irradiation, they experience a series of changes, including shape evolution of individual nanocrystals with the cuboid intermediates, coalescence between nanocrystals, and formation of PbSe thin films through drastic solid-state fusion. Further studies show that the PbSe thin films transform into an amorphous Pb rich phase or eventually pure Pb, which suggest that Se reacts with oxygen and can be evaporated under electron beam illumination. These various in situ and ex situ experimental results indicate that PbSe nanocrystal degradation in air is initiated by the dissociation and removal of ligands from the PbSe nanocrystal surface

Revealing of the Activation Pathway and Cathode Electrolyte Interphase Evolution of Li-Rich 0.5Li2MnO3·0.5LiNi0.3Co0.3Mn0.4O2 Cathode by in Situ Electrochemical Quartz Crystal Microbalance.

The first-cycle behavior of layered Li-rich oxides, including Li2MnO3 activation and cathode electrolyte interphase (CEI) formation, significantly influences their electrochemical performance. However, the Li2MnO3 activation pathway and the CEI formation process are still controversial. Here, the first-cycle properties of xLi2MnO3·(1- x) LiNi0.3Co0.3Mn0.4O2 ( x = 0, 0.5, 1) cathode materials were studied with an in situ electrochemical quartz crystal microbalance (EQCM). The results demonstrate that a synergistic effect between the layered Li2MnO3 and LiNi0.3Co0.3Mn0.4O2 structures can significantly affect the activation pathway of Li1.2Ni0.12Co0.12Mn0.56O2, leading to an extra-high capacity. It is demonstrated that Li2MnO3 activation in Li-rich materials is dominated by electrochemical decomposition (oxygen redox), which is different from the activation process of pure Li2MnO3 governed by chemical decomposition (Li2O evolution). CEI evolution is closely related to Li+ extraction/insertion. The valence state variation of the metal ions (Ni, Co, Mn) in Li-rich materials can promote CEI formation. This study is of significance for understanding and designing Li-rich cathode-based batteries