| 51. |
- Bylund, Emanuel, 1979-, et al.
(författare)
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Does bilingualism come with linguistic costs? A meta-analytic review of the bilingual lexical deficit
- 2023
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Ingår i: Psychonomic Bulletin & Review. - : Springer Science and Business Media LLC. - 1069-9384 .- 1531-5320. ; 30:3, s. 897-913
-
Forskningsöversikt (refereegranskat)abstract
- A series of recent studies have shown that the once-assumed cognitive advantage of bilingualism finds little support in the evidence available to date. Surprisingly, however, the view that bilingualism incurs linguistic costs (the so-called lexical deficit) has not yet been subjected to the same degree of scrutiny, despite its centrality for our understanding of the human capacity for language. The current study implemented a comprehensive meta-analysis to address this gap. By analyzing 478 effect sizes from 130 studies on expressive vocabulary, we found that observed lexical deficits could not be attributed to bilingualism: Simultaneous bilinguals (who acquired both languages from birth) did not exhibit any lexical deficit, nor did sequential bilinguals (who acquired one language from birth and a second language after that) when tested in their mother tongue. Instead, systematic evidence for a lexical deficit was found among sequential bilinguals when tested in their second language, and more so for late than for early second language learners. This result suggests that a lexical deficit may be a phenomenon of second language acquisition rather than bilingualism per se.
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| 52. |
- Bylund, Emanuel, et al.
(författare)
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Does first language maintenance hamper nativelikeness in a second language? : a study of ultimate attainment in early bilinguals
- 2012
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Ingår i: Studies in Second Language Acquisition. - 0272-2631 .- 1470-1545. ; 34:2, s. 215-241
-
Tidskriftsartikel (refereegranskat)abstract
- Within the field of SLA, the incidence of nativelikeness in second language (L2) speakers has typically been explained as a function of age of acquisition. An alternative interpretation, however, is that L2 learners do not attain nativelike proficiency because of first language (L1) maintenance. This interpretation has nevertheless remained mostly theoretical due to the lack of empirical evidence. This study sets out to address the role of L1 proficiency in L2 ultimate attainment by examining L1 and L2 proficiency in 30 early L1 Spanish-L2 Swedish bilinguals. Language proficiency was assessed through grammaticality judgment tests and cloze tests, and additional data on language aptitude were collected through the Swansea Language Aptitude Test (v. 2.0; Meara, Milton, & Lorenzo-Dus, 2002). The results showed positive correlations between nativelike L1 and L2 behavior. Additionally, it was found that language aptitude was positively correlated with nativelike L1 and L2 performance. In view of these findings, it is suggested that (a) L1 maintenance does not hamper L2 nativelikeness and (b) language aptitude is an important factor for bilingual ultimate attainment.
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| 53. |
- Bylund, Emanuel, et al.
(författare)
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Revisiting the bilingual lexical deficit: The impact of age of acquisition
- 2019
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Ingår i: Cognition. - : Elsevier BV. - 0010-0277 .- 1873-7838. ; 182, s. 45-49
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Tidskriftsartikel (refereegranskat)abstract
- Whereas the cognitive advantages brought about by bilingualism have recently been called into question, the so-called ‘lexical deficit’ in bilinguals is still largely taken for granted. Here, we argue that, in analogy with cognitive advantages, the lexical deficit does not apply across the board of bilinguals, but varies as a function of acquisition trajectory. To test this, we implement a novel methodological design, where the variables of bilingualism and first/second language status have been fully crossed in four different groups. While the results confirm effects of bilingualism on lexical proficiency and processing, they show more robust effects of age of acquisition. We conclude that the traditional view of the linguistic costs of bilingualism need to give way to a new understanding of lexical development in which age of acquisition is seen as a major determinant.
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| 54. |
- Bylund, Emanuel, et al.
(författare)
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The role of language aptitude in first language attrition : The case of prepubescent attriters
- 2010
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Ingår i: Applied Linguistics. - : Oxford University Press (OUP). - 0142-6001 .- 1477-450X. ; 31:3, s. 443-464
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Tidskriftsartikel (refereegranskat)abstract
- While language aptitude has been investigated actively within second language research, there is a current dearth of research on the effects of aptitude in cases of attrition. The aim of the present investigation was to explore the role of language aptitude for L1 proficiency in speakers who experienced a break with their L1 setting prior to puberty. Twenty-five L1 SpanishL2 Swedish bilinguals residing in Sweden participated in the study, and 15 native speakers of Spanish living in Chile were recruited as controls. The L1 proficiency was measured by means of a grammaticality judgement test (GJT) and language aptitude data were obtained through the Swansea Language Aptitude Test (Meara et al. 2003). Results showed a positive correlation between GJT performance and language aptitude. More specifically, the bilinguals with above-average aptitude were more likely to score within the native range on the GJT than those with below-average aptitude. It was also seen that among the participants with below-average aptitude, GJT scores were related to daily L1 use. In view of these findings, we suggest that language aptitude has a compensatory function in language attrition, helping the attriter to retain a high level of L1 proficiency despite reduced L1 contact.
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| 55. |
- Bylund Spångberg, Emanuel, 1979-
(författare)
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Age differences in first language attrition : A maturational constraints perspective
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis investigates age-related differences in first language (L1) attrition in a second language (L2) setting. The thesis is based on four individual studies. The aim of each of the studies has been to examine aspects of age differences that to date have remained in the background of attrition research: Study I gives an overview of research on age differences in L1 attrition and suggests a reinterpretation of age effects in attrition, using as a point of departure critical period constructs. Study I also formulates hypotheses regarding the contour and timing of attrition susceptibility and its interplay with non-biological factors. Study II investigates L1 residual knowledge and L2 ultimate attainment in international adoptees. The results suggest that a) that L1 remnants may be found if relearning activities have taken place prior to testing; b) L2 learners who have experienced a complete cut-off in L1 contact do not attain higher L2 proficiency levels than learners who have stayed in contact with the L1. The results also indicate that the level of L1 reactivation and L2 ultimate attainment are related to age of adoption. Study III examines age effects on the retention of L1 event construal patterns. The results show that the onset of puberty is a turning point for the degree of conformity with native behaviour, i.e. those who arrived in the L2 setting before puberty were more likely to exhibit non-converging patterns than those who arrived after puberty. This finding suggests that in attrition conceptual proficiency is equally affected by age as are formal language skills. Finally, Study IV explores the role of language aptitude in prepubescent attriters. The results show that nativelike grammatical intuitions are connected to language aptitude, and that speakers with high levels of language aptitude rely less on L1 contact than do speakers with low levels of language aptitude in their retention of nativelike grammatical intuitions in the L1.
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| 56. |
- Cederblad, Lars, et al.
(författare)
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Classification of Hypoglycemic Events in Type 1 Diabetes Using Machine Learning Algorithms
- 2023
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Ingår i: Diabetes Therapy. - : Springer Nature. - 1869-6953 .- 1869-6961. ; 14:6, s. 953-965
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Tidskriftsartikel (refereegranskat)abstract
- IntroductionTo improve the utilization of continuous- and flash glucose monitoring (CGM/FGM) data we have tested the hypothesis that a machine learning (ML) model can be trained to identify the most likely root causes for hypoglycemic events.MethodsCGM/FGM data were collected from 449 patients with type 1 diabetes. Of the 42,120 identified hypoglycemic events, 5041 were randomly selected for classification by two clinicians. Three causes of hypoglycemia were deemed possible to interpret and later validate by insulin and carbohydrate recordings: (1) overestimated bolus (27%), (2) overcorrection of hyperglycemia (29%) and (3) excessive basal insulin presure (44%). The dataset was split into a training (n = 4026 events, 304 patients) and an internal validation dataset (n = 1015 events, 145 patients). A number of ML model architectures were applied and evaluated. A separate dataset was generated from 22 patients (13 ‘known’ and 9 ‘unknown’) with insulin and carbohydrate recordings. Hypoglycemic events from this dataset were also interpreted by five clinicians independently.ResultsOf the evaluated ML models, a purpose-built convolutional neural network (HypoCNN) performed best. Masking the time series, adding time features and using class weights improved the performance of this model, resulting in an average area under the curve (AUC) of 0.921 in the original train/test split. In the dataset validated by insulin and carbohydrate recordings (n = 435 events), i.e. ‘ground truth,’ our HypoCNN model achieved an AUC of 0.917.ConclusionsThe findings support the notion that ML models can be trained to interpret CGM/FGM data. Our HypoCNN model provides a robust and accurate method to identify root causes of hypoglycemic events.
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| 57. |
- Domange, Raphaël, 1983-
(författare)
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The vowels of Delhi English : Three studies in sociophonetics
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Addressing the dearth of sociolinguistic variation research in the “new” varieties of English (D. Sharma, 2017b), this dissertation consists of a set of three sociophonetic studies on an urban dialect of Indian English. Relying upon community-based methods of data collection, this dissertation examines the vowels of an intergenerational sample of speakers from the upper-middle class neighbourhoods of Delhi. Each study of this compilation is guided by two principal goals. The first one is descriptive, that is to provide a detailed instrumental phonetic characterisation of the phonological vowels that compose the inventory of the variety. The second aim, which is historical, is to shed light of how Indian English carves its own diachronic trajectory, addressing issues relating to, for instance, diachronic stability and the transmission of language change across generations of speakers. Study I thus examines variation in the mid and low back rounded area of the vowel space, and seeks to draw relevant implications from the presence of lexical distributional “archaisms” (Wells, 1982, p. 626) in those vowels. Study II, on the other hand, is concerned with describing a chain-shift-like change in the short front vowels, and discusses the conditions of possibility for such change to occur in a mixed L1-L2 context. Lastly, Study III builds upon a complex allophonic “split” found and summarily described in Study II, and identifies this phenomenon as an element of historical convergence with geographically distant, unrelated, post-colonial varieties of English. Overall, several previously unreported features were found and described in detail in this dissertation, while important clarifications were also brought to areas that have been considered problematic in former descriptive works. Importantly, the studies also demonstrate that the variety under study and its patterns of variation seem to be, in general, amenable to the same kind of empirical analysis as other, so-called “native,” varieties of English, and call into question a number of ordinary assumptions on Indian English.
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| 58. |
- Donoso, Alejandra, 1976-
(författare)
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Expresiones de movimiento en español como segunda lengua y como lengua heredada : Conceptualización y entrega del Camino, la Manera y la Base
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The current thesis is based on four individual studies which aim to account for the expression of motion events (ME) in Spanish and Swedish as first languages (L1), in Swedish as a second language (L2), and in Spanish as a heritage language (SHL). The data, resulting from audio-recordings of different sorts of stimuli, have been analyzed with special focus on (1) the most common structures used for referring to various types of ME, (2) the types and amount of information provided by the participants, in particular as regards the semantic components Path, Manner and Ground, and (3) grammatical aspect and types of syntactic structures resorted to, including the correlation between the two latter factors and speakers’ discursive preferences. Study 1 sets out to explore how Spanish and Swedish native speakers convey information about motion. The results show that the Swedish L1 speakers produced a wider range of descriptions concerning Manner and Path than the Spanish L1 speakers; furthermore, both groups delivered detailed Ground descriptions, although the Swedish native speakers expressed final destinations (endpoints) of ME to a greater extent. Study 2 aims to investigate to what extent Swedish L1 patterns for motion encoding are still at play in the acquisition of Spanish L2 even at advanced stages of L2 acquisition. The results show that the learner group used a larger amount of Path particles and Ground adjuncts (in particular those referring to endpoints) than did the Spanish natives; this finding supports the claim that L2 learners rely on the lexicalization patterns of their L1 when describing ME in an L2. As for Manner, the L2 speakers were found to express this component mainly outside the verb, and to deliver more information about Manner than the Spanish natives. Study 3 addresses the construal of ME in Swedish speakers of L2 Spanish, in particular concerning the encoding of motion endpoints and Manner of motion. The results show that the Swedish learners of Spanish exhibited the same, high frequencies of endpoint marking as did their monolingual Swedish peers, thus deviating from the Spanish native pattern. Moreover, the L2 speakers used the same amount of Manner verbs as did the Spanish natives but tended consistently to provide additional Manner information in periphrastic constructions. Finally, Study 4 sets out to analyze the ways in which L1 Spanish/L2 Swedish early and late bilinguals express ME in SHL. The aim is to show in which ways and to what extent the typological patterns for motion encoding in the L2 may impact on motion encoding in the L1 with regard to three parameters: (1) age of onset (AO) of the acquisition of L2, (2) length of residence (LoR) in the L2 environment and (3) contact level with the L1 (CL). The focus data, consisting of oral re-tellings produced by the bilinguals, were compared to analogous data produced by two control groups (native speakers of Spanish and Swedish) in order to analyze conflation patterns regarding Manner, Path and Ground information. The analysis points to the conclusion that both the individuals’ AO of L2 acquisition and their LoR in the L2 environment have affected their L1 conceptualization patterns while their CL plays a subordinate role. In summary, the findings lend support to the idea that the habitual conceptualization of events in the L1 influences L2 acquisition; conversely, the conceptual patterns of the L2 have an impact on L1 usage in bilinguals, especially in combination with an early AO and a long LoR.
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| 59. |
- Douglas, Andrew, et al.
(författare)
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Platelet-rich emboli are associated with von Willebrand factor levels and have poorer revascularization outcomes.
- 2020
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Ingår i: Journal of neurointerventional surgery. - : BMJ. - 1759-8486 .- 1759-8478. ; 12:6
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Tidskriftsartikel (refereegranskat)abstract
- Platelets and von Willebrand factor (vWF) are key factors in thrombosis and thus are likely key components of acute ischemic stroke (AIS) emboli. We aimed to characterize platelet and vWF levels in AIS emboli and to assess associations between their expression levels and clinical and procedural information.Histopathological and immunohistochemical analysis of emboli collected as part of the multi-institutional RESTORE registry was performed. The composition of the emboli was quantified using Orbit Image Analysis machine learning software. Correlations between clot components and clinical and procedural information were assessed using the χ2 test.Ninety-one emboli samples retrieved from 63 patients were analyzed in the study. The mean platelet (CD42b) content of the clots was 33.9% and the mean vWF content of the clots was 29.8%. There was a positive correlation between platelet and vWF levels (ρ=0.564, p<0.001*, n=91). There was an inverse correlation between both platelets and vWF levels and percentage of red blood cells (RBCs) in the emboli (CD42b vs RBC: ρ=-0.535, p<0.001*, n=91; vWF vs RBC: ρ=-0.366, p<0.001*, n=91). Eighty-one percent of patients in the low platelet group had a good revascularization outcome (Thrombolysis in Cerebral Infarction 2c/3) compared with 58% in the high platelet group (χ2=5.856, p=0.016).Platelet and vWF levels in AIS emboli correlate with each other and both have an inverse relationship with RBC composition. Patients with platelet-rich clots have poorer revascularization outcomes.
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| 60. |
- Eriksson, Jan, et al.
(författare)
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Altered glucose-dependent secretion of glucagon and ACTH is associated with insulin resistance, assessed by population analysis
- 2023
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Ingår i: Endocrine Connections. - : Bioscientifica. - 2049-3614. ; 12:4
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to characterize how the dysregulation of counter-regulatory hormones can contribute to insulin resistance and potentially to diabetes. Therefore, we investigated the association between insulin sensitivity and the glucose- and insulin-dependent secretion of glucagon, adrenocorticotropic hormone (ACTH), and cortisol in non-diabetic individuals using a population model analysis. Data, from hyperinsulinemic-hypoglycemic clamps, were pooled for analysis, including 52 individuals with a wide range of insulin resistance (reflected by glucose infusion rate 20-60 min; GIR(20-60min)). Glucagon secretion was suppressed by glucose and, to a lesser extent, insulin. The GIR(20-60min) and BMI were identified as predictors of the insulin effect on glucagon. At normoglycemia (5 mmol/L), a 90% suppression of glucagon was achieved at insulin concentrations of 16.3 and 43.4 mu U/mL in individuals belonging to the highest and lowest quantiles of insulin sensitivity, respectively. Insulin resistance of glucagon secretion explained the elevated fasting glucagon for individuals with a low GIR(20-60min). ACTH secretion was suppressed by glucose and not affected by insulin. The GIR(20-60min) was superior to other measures as a predictor of glucose-dependent ACTH secretion, with 90% suppression of ACTH secretion by glucose at 3.1 and 3.5 mmol/L for insulin-sensitive and insulin-resistant individuals, respectively. This difference may appear small but shifts the suppression range into normoglycemia for individuals with insulin resistance, thus, leading to earlier and greater ACTH/cortisol response when the glucose falls. Based on modeling of pooled glucose-clamp data, insulin resistance was associated with generally elevated glucagon and a potentiated cortisol-axis response to hypoglycemia, and over time both hormonal pathways may therefore contribute to dysglycemia and possibly type 2 diabetes.
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