29 research outputs found

    To What Extent is Collocation Knowledge Associated with Oral Proficiency? A Corpus-Based Approach to Word Association

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    This study examined the relationship between second language (L2) learners’ collocation knowledge and oral proficiency. A new approach to measuring collocation was adopted by eliciting responses through a word association task and using corpus-based measures (absolute frequency count, t-score, MI score) to analyze the degree to which stimulus words and responses were collocated. Oral proficiency was measured using human judgements and objective measures of fluency (articulation rate, silent pause ratio, filled pause ratio) and lexical richness (diversity, frequency, range). Forty Japanese university students completed a word association task and a spontaneous speaking task (picture narrative). Results indicated that speakers who used more low-frequency collocations in the word association task (i.e., lower collocation frequency scores) spoke faster with fewer silent pauses and were perceived to be more fluent. Speakers who provided more strongly associated collocations (as measured by MI) used more sophisticated lexical items and were perceived to be lexically proficient. Collocation knowledge remained as a unique predictor after the influence of learners’ vocabulary size (i.e., knowledge of single-word items) was considered. These findings support the key role that collocation plays in oral proficiency and provide important insights into understanding L2 speech development from the perspective of phraseological competence

    Combining tower mixing ratio and community model data to estimate regional-scale net ecosystem carbon exchange by boundary layer inversion over 4 flux towers in the U.S.A.

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    We evaluated an idealized boundary layer (BL) model with simple parameterizations using vertical transport information from community model outputs (NCAR/NCEP Reanalysis and ECMWF Interim Analysis) to estimate regional-scale net CO2 fluxes from 2002 to 2007 at three forest and one grassland flux sites in the United States. The BL modeling approach builds on a mixed-layer model to infer monthly average net CO2 fluxes using high-precision mixing ratio measurements taken on flux towers. We compared BL model net ecosystem exchange (NEE) with estimates from two independent approaches. First, we compared modeled NEE with tower eddy covariance measurements. The second approach (EC-MOD) was a data-driven method that upscaled EC fluxes from towers to regions using MODIS data streams. Comparisons between modeled CO2 and tower NEE fluxes showed that modeled regional CO2 fluxes displayed interannual and intra-annual variations similar to the tower NEE fluxes at the Rannells Prairie and Wind River Forest sites, but model predictions were frequently different from NEE observations at the Harvard Forest and Howland Forest sites. At the Howland Forest site, modeled CO2 fluxes showed a lag in the onset of growing season uptake by 2 months behind that of tower measurements. At the Harvard Forest site, modeled CO2 fluxes agreed with the timing of growing season uptake but underestimated the magnitude of observed NEE seasonal fluctuation. This modeling inconsistency among sites can be partially attributed to the likely misrepresentation of atmospheric transport and/or CO2gradients between ABL and the free troposphere in the idealized BL model. EC-MOD fluxes showed that spatial heterogeneity in land use and cover very likely explained the majority of the data-model inconsistency. We show a site-dependent atmospheric rectifier effect that appears to have had the largest impact on ABL CO2 inversion in the North American Great Plains. We conclude that a systematic BL modeling approach provided new insights when employed in multiyear, cross-site synthesis studies. These results can be used to develop diagnostic upscaling tools, improving our understanding of the seasonal and interannual variability of surface CO2 fluxes

    Delayed winter supplemental feeding and year-round mineral supplementation of beef cows on native range

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    Polled Hereford cows on native Flint Hills pasture not supplemented until February lost more weight from December to February, lost less from February to May, and were in poorer condition before calving than cows supplemented beginning in November. But calf survival, birth weight, and calf average daily gain were similar for both groups. Feeding cows a calcium, phosphorus, trace mineral mix did not improve any measure of cow or calf performance

    The contribution of general language ability, reading comprehension and working memory to mathematics achievement among children with English as additional language (EAL): an exploratory study

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    An increasing number of high-stakes mathematics standardised tests around the world place an emphasis on using mathematical word problems to assess students’ mathematical understanding. Not only do these assessments require children to think mathematically, but making sense of these tests’ mathematical word problems also brings children’s language ability, reading comprehension and working memory into play. The nature of these test items places a great deal of cognitive demand on all mathematics learners, but particularly on children completing the assessments in a second language that is still developing. This paper reports findings from an exploratory study on the contribution of language to mathematics achievement among 35 children with English as an Additional Language (EAL) and 31 children with English as their first language (FLE). The findings confirm the prominent role of general language ability in the development and assessment of mathematical ability. This variable explained more variance than working memory in word-based mathematics scores for all learners. Significant differences were found between the performance of FLE learners and EAL learners on solving mathematical word-based problems, but not on wordless problems. We conclude that EAL learners need to receive more targeted language support, including help with specific language knowledge needed to understand and solve mathematical word problems

    Investigating the extent to which vocabulary knowledge and skills can predict aspects of fluency for a small group of pre-intermediate Japanese L1 users of English (L2)

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    This chapter explores relationships between vocabulary knowledge and fluent speech. The reporting of multiple vocabulary task scores is an emerging trend in vocabulary research (Clenton et al., 2019; Fitzpatrick & Clenton, 2017) and while fluency papers (De Jong et al., 2013; 2015) report significant relationships with vocabulary measures, these are limited to reporting single vocabulary task scores, and to proficient participants. The current chapter, therefore, reports on a multifaceted approach to exploring vocabulary measures and L2 fluency, with pre-intermediate proficiency learners. Participants completed two vocabulary measures: Lex30 (Meara & Fitzpatrick, 2000), and a vocabulary size task, in a multiple-choice format; and X_Lex (Meara & Milton, 2003), a receptive vocabulary yes/no task. We investigated fluency using measures and indices from earlier fluency papers (De Jong et al., 2013; 2015; De Jong & Mora, 2017). A comparison between the current chapter findings and those from these earlier studies suggests that relationships appear to differ according to proficiency level. We discuss these findings in terms of second language acquisition and consider future implications for future investigations into the relationship between vocabulary and L2 fluency at different proficiency levels.Theoretical and Experimental LinguisticsTeaching and Teacher Learning (ICLON

    Risk of Bowel Obstruction in Patients Undergoing Neoadjuvant Chemotherapy for High-risk Colon Cancer: A Nested Case-control-matched Analysis of an International, Multicenter, Randomized Controlled Trial (FOxTROT)

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    OBJECTIVE: This study aimed to identify risk criteria available before the point of treatment initiation that can be used to stratify the risk of obstruction in patients undergoing neoadjuvant chemotherapy (NAC) for high-risk colon cancer. BACKGROUND: Global implementation of NAC for colon cancer, informed by the FOxTROT trial, may increase the risk of bowel obstruction. METHODS: A case-control study, nested within an international randomized controlled trial (FOxTROT; ClinicalTrials.gov: NCT00647530). Patients with high-risk operable colon cancer (radiologically staged T3-4 N0-2 M0) that were randomized to NAC and developed large bowel obstruction were identified. First, clinical outcomes were compared between patients receiving NAC in FOxTROT who did and did not develop obstruction. Second, obstructed patients (cases) were age-matched and sex-matched with patients who did not develop obstruction (controls) in a 1:3 ratio using random sampling. Bayesian conditional mixed-effects logistic regression modeling was used to explore clinical, radiologic, and pathologic features associated with obstruction. The absolute risk of obstruction based on the presence or absence of risk criteria was estimated for all patients receiving NAC. RESULTS: Of 1053 patients randomized in FOxTROT, 699 received NAC, of whom 30 (4.3%) developed obstruction. Patients underwent care in European hospitals including 88 UK, 7 Danish, and 3 Swedish centers. There was more open surgery (65.4% vs 38.0%, P=0.01) and a higher pR1 rate in obstructed patients (12.0% vs 3.8%, P=0.004), but otherwise comparable postoperative outcomes. In the case-control–matched Bayesian model, 2 independent risk criteria were identified: (1) obstructing disease on endoscopy and/or being unable to pass through the tumor [adjusted odds ratio: 9.09, 95% credible interval: 2.34–39.66] and stricturing disease on radiology or endoscopy (odds ratio: 7.18, 95% CI: 1.84–32.34). Three risk groups were defined according to the presence or absence of these criteria: 63.4% (443/698) of patients were at very low risk (10%). CONCLUSIONS: Safe selection for NAC for colon cancer can be informed by using 2 features that are available before treatment initiation and identifying a small number of patients with a high risk of preoperative obstruction

    Non-IDH1-R132H IDH1/2 mutations are associated with increased DNA methylation and improved survival in astrocytomas, compared to IDH1-R132H mutations

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    Somatic mutations in the isocitrate dehydrogenase genes IDH1 and IDH2 occur at high frequency in several tumour types. Even though these mutations are confined to distinct hotspots, we show that gliomas are the only tumour type with an exceptionally high percentage of IDH1(R132H) mutations. Patients harbouring IDH1(R132H) mutated tumours have lower levels of genome-wide DNA-methylation, and an associated increased gene expression, compared to tumours with other IDH1/2 mutations ("non-R132H IDH1/2 mutations"). This reduced methylation is seen in multiple tumour types and thus appears independent of the site of origin. For 1p/19q non-codeleted glioma (astrocytoma) patients, we show that this difference is clinically relevant: in samples of the randomised phase III CATNON trial, patients harbouring tumours with IDH mutations other than IDH1(R132H) have a better outcome (hazard ratio 0.41, 95% CI [0.24, 0.71], p = 0.0013). Such non-R132H IDH1/2-mutated tumours also had a significantly lower proportion of tumours assigned to prognostically poor DNA-methylation classes (p < 0.001). IDH mutation-type was independent in a multivariable model containing known clinical and molecular prognostic factors. To confirm these observations, we validated the prognostic effect of IDH mutation type on a large independent dataset. The observation that non-R132H IDH1/2-mutated astrocytomas have a more favourable prognosis than their IDH1(R132H) mutated counterpart indicates that not all IDH-mutations are identical. This difference is clinically relevant and should be taken into account for patient prognostication.MTG6Molecular tumour pathology - and tumour genetic

    Risk of Bowel Obstruction in Patients Undergoing Neoadjuvant Chemotherapy for High-risk Colon Cancer

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    Objective: This study aimed to identify risk criteria available before the point of treatment initiation that can be used to stratify the risk of obstruction in patients undergoing neoadjuvant chemotherapy (NAC) for high-risk colon cancer. Background: Global implementation of NAC for colon cancer, informed by the FOxTROT trial, may increase the risk of bowel obstruction. Methods: A case-control study, nested within an international randomized controlled trial (FOxTROT; ClinicalTrials.gov: NCT00647530). Patients with high-risk operable colon cancer (radiologically staged T3-4 N0-2 M0) that were randomized to NAC and developed large bowel obstruction were identified. First, clinical outcomes were compared between patients receiving NAC in FOxTROT who did and did not develop obstruction. Second, obstructed patients (cases) were age-matched and sex-matched with patients who did not develop obstruction (controls) in a 1:3 ratio using random sampling. Bayesian conditional mixed-effects logistic regression modeling was used to explore clinical, radiologic, and pathologic features associated with obstruction. The absolute risk of obstruction based on the presence or absence of risk criteria was estimated for all patients receiving NAC. Results: Of 1053 patients randomized in FOxTROT, 699 received NAC, of whom 30 (4.3%) developed obstruction. Patients underwent care in European hospitals including 88 UK, 7 Danish, and 3 Swedish centers. There was more open surgery (65.4% vs 38.0%, P=0.01) and a higher pR1 rate in obstructed patients (12.0% vs 3.8%, P=0.004), but otherwise comparable postoperative outcomes. In the case-control–matched Bayesian model, 2 independent risk criteria were identified: (1) obstructing disease on endoscopy and/or being unable to pass through the tumor [adjusted odds ratio: 9.09, 95% credible interval: 2.34–39.66] and stricturing disease on radiology or endoscopy (odds ratio: 7.18, 95% CI: 1.84–32.34). Three risk groups were defined according to the presence or absence of these criteria: 63.4% (443/698) of patients were at very low risk (10%). Conclusions: Safe selection for NAC for colon cancer can be informed by using 2 features that are available before treatment initiation and identifying a small number of patients with a high risk of preoperative obstruction

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