Cognitive Mechanisms Underlying Second Language Listening Comprehension

This dissertation research investigates the cognitive mechanisms underlying second language (L2) listening comprehension. I use three types of sentential contexts, congruent, neutral and incongruent, to look at how L2 learners construct meaning in spoken sentence comprehension. The three types of contexts differ in their context predictability. The last word in a congruent context is highly predictable (e.g., Children are more affected by the disease than adults), the last word in a neutral context is likely but not highly predictable (e.g., Children are more affected by the disease than nurses), and the last word in an incongruent context is impossible (e.g., Children are more affected by the disease than chairs). The study shows that, for both native speakers and L2 learners, a consistent context facilitates word recognition. In contrast, an inconsistent context inhibits native speakers’ word recognition but not that of L2 learners. I refer to this new discovery as the facilitation-without-inhibition phenomenon in L2 listening comprehension. Results from follow-up experiments show that this facilitation-without-inhibition phenomenon is a result of insufficient suppression by L2 learners

The scale and evolutionary significance of horizontal gene transfer in the choanoflagellate

Background It is generally agreed that horizontal gene transfer (HGT) is common in phagotrophic protists. However, the overall scale of HGT and the cumulative impact of acquired genes on the evolution of these organisms remain largely unknown. Results Choanoflagellates are phagotrophs and the closest living relatives of animals. In this study, we performed phylogenomic analyses to investigate the scale of HGT and the evolutionary importance of horizontally acquired genes in the choanoflagellate Monosiga brevicollis. Our analyses identified 405 genes that are likely derived from algae and prokaryotes, accounting for approximately 4.4% of the Monosiga nuclear genome. Many of the horizontally acquired genes identified in Monosiga were probably acquired from food sources, rather than by endosymbiotic gene transfer (EGT) from obsolete endosymbionts or plastids. Of 193 genes identified in our analyses with functional information, 84 (43.5%) are involved in carbohydrate or amino acid metabolism, and 45 (23.3%) are transporters and/or involved in response to oxidative, osmotic, antibiotic, or heavy metal stresses. Some identified genes may also participate in biosynthesis of important metabolites such as vitamins C and K12, porphyrins and phospholipids. Conclusions Our results suggest that HGT is frequent in Monosiga brevicollis and might have contributed substantially to its adaptation and evolution. This finding also highlights the importance of HGT in the genome and organismal evolution of phagotrophic eukaryotes

Development of a Mechanistic Method to Obtain Load Position Strain in Instrumented Pavement

To study the in-situ response and performance of asphalt pavement, instrumenting pavement with a variety of sensors has become one of the most important tools in the field or accelerated load facilities. In the dynamic response collection process, engineers are more concerned with the load position strain of the pavement structure due to wheel wander. This paper proposes a method to obtain the load position and the strain at the load position when there is no lateral-axis positioning system based on multilayer elastic theory. The test section was paved in the field with installed strain sensors to verify and apply the proposed method. The verification results showed that both the calculated load position and load position strain matched the measured values with an absolute difference range of 5–60 mm, 0.5–2.5 με, respectively. The application results showed that the strain at the load position calculated by the proposed method had a good correlation with the temperature, as expected

The pragmatic function of intonation: cueing agreement and disagreement in spoken English discourse and implications for ELT

Although prosody is central to the interpretation of spoken language and understanding of speaker intent, it has traditionally been neglected in cross-cultural studies of pragmatics and overlooked in ESL/ EFL materials. This study investigates prosodic (mis)matching to indicate (dis)agreement by native speakers of American English (AES) and Chinese learners of English (CLsE) in order to contribute to our understanding of cross-cultural manifestations of speech acts and the study of second language intonation acquisition and teaching. Twelve AESs and 12 CLsE completed an interactive preference task in pairs. Each pair viewed ten pictures of concept cars and was asked to browse through the pictures and agree together on one of the ten cars as their top choice. Their conversations were audiotaped using headset microphones and analyzed using a Kay Elemetrics Computerized Speech Laboratory. (Dis)agreement sequences were coded for pitch (mis)matching using Brazil’s (The communicative value of intonation in English. Cambridge University Press, Cambridge, 1997) model of discourse intonation. The results showed that both AESs and CLsE manifested pitch concord in the majority of agreement sequences. However, while AESs consistently used pitch mismatching as a cue to signal disagreement with their interlocutor, this was not the case in the CLsE discourse, suggesting that pedagogical intervention may be appropriate

The activation of grammaticalized meaning in L2 processing: Toward an explanation of the morphological congruency effect

© 2015, © The Author(s) 2015. Objectives: The study was intended to test the hypothesis that L2 speakers have difficulty in automatically activating a grammaticalized L2 meaning that is not morphologically marked in L1. Methodology: The study consisted of three experiments. A sentence–picture matching task was designed to assess the activation of grammaticalized meaning. The participants were asked to judge if a sentence correctly described the physical relationships of three objects in a picture. Hidden in the stimuli that required a positive response was a number agreement manipulation whereby a noun phrase in the sentence may agree or disagree with the number of objects in the picture. A number disagreement effect, as shown in a delay in producing a positive response on items of number disagreement was used to assess automatic activation of number meanings. Data and Analysis: The data constituted reaction times and accuracy rates from 32 English native speakers, 36 Chinese native speakers, 54 Chinese–English bilinguals, and 26 Russian–English bilinguals. Analyses of variance were performed in analyzing these data. Findings: The results showed a number disagreement effect in L1 and L2 among Russian English as a second language (ESL) speakers only. Chinese ESL speakers showed no difference between the two critical conditions in either language. A follow-up experiment showed that Chinese ESL speakers had no difficulty in automatically activating number meanings which were expressed lexically in English sentence processing. These findings provided support for the idea that the well documented difficulty L2 learners have in learning incongruent L2 inflectional morphemes may have to do with their difficulty in automatically activating a grammaticalized meaning that is not grammaticalized in their L1. Originality: The sentence–picture matching task represented a unique and effective approach to the study of the activation of grammaticalized meanings. Significance: The findings from the study represented some first psycholinguistic evidence regarding the activation of grammaticalized meanings among non-native speakers