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This study investigated the effects of two different planning time conditions (i.e., operational [20 s] and extended length [90 s]) for the lecture listening-into-speaking tasks of the "TOEFL iBT"® test for candidates at different proficiency levels. Seventy international students based in universities and language schools in the United Kingdom (35 at a lower level; 35 at a higher level) participated in the study. The effects of different lengths of planning time were examined in terms of: (1) the scores given by ETS-certified raters; (2) the quality of the speaking performances characterized by accurately reproduced idea units and the measures of complexity, accuracy, and fluency; and (3) self-reported use of cognitive and metacognitive processes and strategies during listening, planning, and speaking. The results found neither a statistically significant main effect of the length of planning time nor an interaction between planning time and proficiency on the scores or on the quality of the speaking performance. There were several cognitive and metacognitive processes and strategies where significantly more engagement was reported under the extended planning time, which suggests enhanced cognitive validity of the task. However, the increased engagement in planning did not lead to any measurable improvement in the score. Therefore, in the interest of practicality, the results of this study provide justifications for the operational length of planning time for the lecture listening-into-speaking tasks in the speaking section of the TOEFL iBT test.

This paper investigates the comparability between the video-conferencing and face-to-face modes of the IELTS Speaking Test in terms of scores and language functions generated by test-takers. Data were collected from 10 trained IELTS examiners and 99 test-takers who took two speaking tests under face-to-face and video-conferencing conditions. Many-facet Rasch Model (MFRM) analysis of test scores indicated that the delivery mode did not make any meaningful difference to test-takers' scores. An examination of language functions revealed that both modes equally elicited the same language functions except "asking for clarification." More test-takers made clarification requests in the video-conferencing mode (63.3%) than in the face-to-face mode (26.7%). Drawing on the findings, as well as practical implications, we extend emerging thinking about video-conferencing speaking assessment and the associated features of this modality in its own right.

This mixed methods study compared IELTS examiners' scores when assessing spoken performances under live and two 'non-live' testing conditions using audio and video recordings. Six IELTS examiners assessed 36 test-takers' performances under the live, audio, and video rating conditions. Scores in the three rating modes were calibrated using the many-facet Rasch model (MFRM). For all three modes, examiners provided written justifications for their ratings, and verbal reports were also collected to gain insights into examiner perceptions towards performance under the audio and video conditions. Results showed that, for all rating criteria, audio ratings were significantly lower than live and video ratings. Examiners noticed more negative performance features under the two non-live rating conditions, compared to the live condition. However, richer information about test-taker performance in the video mode appeared to cause raters to rely less on such negative evidence than audio raters when awarding scores. Verbal report data showed that having visual information in the video-rating mode helped examiners to understand what the test-takers were saying, to comprehend better what test-takers were communicating using non-verbal means, and to understand with greater confidence the source of test-takers' hesitation, pauses, and awkwardness.

Droplet spreading is ubiquitous and plays a significant role in liquid-based energy systems, thermal management devices and microfluidics. While the spreading of non-volatile droplets is quantitatively understood, the spreading and flow transition in volatile droplets remains elusive due to the complexity added by interfacial phase change and non-equilibrium thermal transport. Here we show, using both mathematical modelling and experiments, that the wetting dynamics of volatile droplets can be scaled by the spatial-temporal interplay between capillary, evaporation and thermal Marangoni effects. We elucidate and quantify these complex interactions using phase diagrams based on systematic theoretical and experimental investigations. A spreading law of evaporative droplets is derived by extending Tanner's law (valid for non-volatile liquids) to a full range of liquids with saturation vapour pressure spanning from 101 to 104 Pa and on substrates with thermal conductivity from 10-1 to 103 W m-1 K-1. In addition to its importance in fluid-based industries, the conclusions also enable a unifying explanation to a series of individual works including the criterion of flow reversal and the state of dynamic wetting, making it possible to control liquid transport in diverse application scenarios. [ABSTRACT FROM AUTHOR]