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Spatial skills first: The importance of mental rotation for arithmetic skill acquisition Georges, Carrie ; Cornu, Véronique ; Schiltz, Christine Poster (2017, September) Detailed reference viewed: 68 (5 UL)Project NUMTEST: Assessing basic number competence without language Greisen, Max ; Hornung, Caroline ; Martin, Romain et al Poster (2017, May 31) While numerical skills are fundamental in modern societies, some estimated 5-7% of children suffer from a mathematical learning disorder, called developmental dyscalculia (DD). Nevertheless, universally ... [more ▼] While numerical skills are fundamental in modern societies, some estimated 5-7% of children suffer from a mathematical learning disorder, called developmental dyscalculia (DD). Nevertheless, universally valid diagnostic instruments are still lacking, as all current DD test batteries are based on language instructions. Consequently, their measurements are tightly linked to the specific language context of test administration and thus their results cannot easily be compared across countries. Here we are showing results of the first pilot study of a research project that aims to develop a test for basic math abilities that does not rely on language instruction and minimizes language use. To this aim, video and animation based instructions were implemented on touchscreen devices. A first version of the tasks has been tested with two samples of first grade children in Luxembourg’s fundamental schools, of which half completed the same tasks with traditional verbal instructions. Our results indicate that performance in the experimental group was similar or better than the control group using verbal instructions. Relationships between linguistic background and the sample’s performance on one hand and qualitative usability aspects of nonverbal task instruction and tablet-pc use with young children will be discussed. [less ▲] Detailed reference viewed: 56 (11 UL)Mathematical abilities in elementary school: Do they relate to number–space associations? Georges, Carrie ; Hoffmann, Danielle ; Schiltz, Christine in Journal of Experimental Child Psychology (2017) Considering the importance of mathematics in Western societies, it is crucial to understand the cognitive processes involved in the acquisition of more complex mathematical skills. The current study ... [more ▼] Considering the importance of mathematics in Western societies, it is crucial to understand the cognitive processes involved in the acquisition of more complex mathematical skills. The current study, therefore, investigated how the quality of number–space mappings on the mental number line, as indexed by the parity SNARC (spatial–numerical association of response codes) effect, relates to mathematical performances in third- and fourth-grade elementary school children. Mathematical competencies were determined using the “Heidelberger Rechentest,” a standardized German math test assessing both arithmetical and visuospatial math components. Stronger parity SNARC effects significantly related to better arithmetical but not visuospatial math abilities, albeit only in the relatively younger children. These findings highlight the importance of spatial–numerical interactions for arithmetical (as opposed to visuospatial) math skills at the fairly early stages of mathematical development. Differential relations might be explained by the reliance on problem-solving strategies involving number–space mappings only for arithmetic tasks mainly in younger children. [less ▲] Detailed reference viewed: 139 (11 UL)Training early visuo-spatial abilities: A controlled classroom-based intervention study. Cornu, Véronique ; Schiltz, Christine ; Pazouki, Tahereh et al in Applied Developmental Science (2017) Visuo-spatial training can be considered as a promising approach to provide young children with a sound foundation for later mathematical learning. We developed and implemented a tablet-based visuo ... [more ▼] Visuo-spatial training can be considered as a promising approach to provide young children with a sound foundation for later mathematical learning. We developed and implemented a tablet-based visuo-spatial intervention in kindergarten classrooms aiming to foster the development of children’s visuo-spatial and numerical abilities. A sample of N = 125 children participated in the present study, 68 children were part of the intervention group and participated in 20 training sessions of 20 minutes over a 10-week period, 57 children formed a business as usual control group. Results show that, at this young age, visuo-spatial and early math skills are already strongly interlinked. However, the training effects were domain-specific as they only improved visuo-spatial skills, but did not transfer to early math performance in the present setting. [less ▲] Detailed reference viewed: 255 (66 UL)Are parity and magnitude status of Arabic digits processed automatically? An EEG study using the fast periodic visual stimulation Poncin, Alexandre ; ; Guillaume, Mathieu et al Presentation (2017, February 22) Many studies have shown that humans can easily extract numerical characteristics of single digits such as numerical magnitude and parity status. We investigated whether spontaneous processing of magnitude ... [more ▼] Many studies have shown that humans can easily extract numerical characteristics of single digits such as numerical magnitude and parity status. We investigated whether spontaneous processing of magnitude or parity status can be observed when participants are passively presented with sequences of briefly displayed Arabic digits. We assessed the parity processing by presenting seven odd digit numbers followed by one even digit (and reverse) with a sinusoidal contrast modulation at a frequency of 10HZ in one-minute sequences. The same paradigm and frequencies were used to investigate magnitude processing (i.e. seven digits smaller than five followed by one digit larger than five; and reverse) and control condition (i.e. sequence of 1-4-6-9 followed by 2-3-7 or 8). We observed a strong EEG activation on right parietal electrodes and a weaker activation on left parietal electrodes in all conditions. Left and right activations were stronger in the parity than in the other conditions, reflecting an automatic retrieval of parity information conveyed by the Arabic digits. The weaker activation during the magnitude task could reflect a more complicated access of the information corresponding to magnitude status. Right activations during the control task could be due to the fact that subjects can quickly learn to categorize numbers arbitrarily. These neuronal activation patterns are consistent with the neuro-imaging literature describing the localization of basic numerical processing. Our findings indicate that magnitude and parity status are extracted automatically from Arabic digits, even when numerical stimuli are presented without instructions at a high presentation rate. [less ▲] Detailed reference viewed: 75 (12 UL)Project NUMTEST; Assessing basic number competence without language Greisen, Max ; Schiltz, Christine ; Hornung, Caroline et al Poster (2017, February 20) While numerical skills are fundamental in modern societies, some estimated 5-7% of children suffer from a mathematical learning disorder, called developmental dyscalculia (DD). Nevertheless, universally ... [more ▼] While numerical skills are fundamental in modern societies, some estimated 5-7% of children suffer from a mathematical learning disorder, called developmental dyscalculia (DD). Nevertheless, universally valid diagnostic instruments are still lacking, as all current DD test batteries are based on language instructions. Consequently their measurements are tightly linked to the specific language context of test administration and thus their results cannot easily be compared across countries. The present study is the first pilot study of a research project that aims to develop a test for basic math abilities that does not rely on language instruction and minimizes language use. To this aim, video and animation based instructions were implemented on touchscreen devices. A first version of the application has been tested with a sample of first grade children in Luxembourg’s fundamental schools, of which half used the same application but with traditional German instructions. First results indicate that performance in the experimental group was similar to the control group using verbal instructions. Relationships between linguistic background and the sample’s performance on one hand and qualitative usability aspects of nonverbal task instruction and tablet use with young children will be discussed. [less ▲] Detailed reference viewed: 105 (22 UL)LEARN Newsletter - Editioun 2017: Méisproochegkeet Hoffmann, Danielle ; Hornung, Caroline ; Martin, Romain et al Book published by LEARN (2017) Detailed reference viewed: 78 (11 UL)Assessing the cerebral correlates of non-symbolic number processing with fast periodic visual stimulation Guillaume, Mathieu ; ; et al Poster (2017) Some authors recently challenged the claim that numerical processes specifically handle non-symbolic magnitudes and they alternately suggested that general visual and/or control executive processes could ... [more ▼] Some authors recently challenged the claim that numerical processes specifically handle non-symbolic magnitudes and they alternately suggested that general visual and/or control executive processes could explain performance in number comparison tasks. To further investigate this issue, we set up an EEG paradigm in which we recorded neural responses to the passive viewing of different arrays of basic visual forms. The stimuli sequence followed a fast and sinusoidal contrast modulation at the frequency of 10Hz (ten items per second). Visual properties of elements randomly changed from item to item, but their number was manipulated: in a control condition, arrays always contained the same number, and in the experimental conditions, the number periodically changed (each eight iteration, at 1.25Hz). We varied the numerical ratio between the frequent and the rare number throughout the experimental conditions. We recorded significant responses on occipital and parietal electrodes to the oddball frequency and its harmonics during our experimental conditions. Crucially, the strength of the signal was proportionally larger when the numerical ratio was larger. The results suggest that implicit and passive viewing of quick sequence of arrays was sufficient to automatically elicit neural synchronisation to numerical magnitudes without any explicit involvement of higher general cognitive processes. [less ▲] Detailed reference viewed: 57 (6 UL)How Do Different Aspects of Spatial Skills Relate to Early Arithmetic and Number Line Estimation? Cornu, Véronique ; Hornung, Caroline ; Schiltz, Christine et al in Journal of Numerical Cognition (2017), 3(2), The present study investigated the predictive role of spatial skills for arithmetic and number line estimation in kindergarten children (N = 125). Spatial skills are known to be related to mathematical ... [more ▼] The present study investigated the predictive role of spatial skills for arithmetic and number line estimation in kindergarten children (N = 125). Spatial skills are known to be related to mathematical development, but due to the construct’s non-unitary nature, different aspects of spatial skills need to be differentiated. In the present study, a spatial orientation task, a spatial visualization task and visuo-motor integration task were administered to assess three different aspects of spatial skills. Furthermore, we assessed counting abilities, knowledge of Arabic numerals, quantitative knowledge, as well as verbal working memory and verbal intelligence in kindergarten. Four months later, the same children performed an arithmetic and a number line estimation task to evaluate how the abilities measured at time 1 predicted early mathematics outcomes. Hierarchical regression analysis revealed that children’s performance in arithmetic was predicted by their performance in the spatial orientation and visuo-motor integration task, as well as their knowledge of the Arabic numerals. Performance in number line estimation was significantly predicted by the children’s spatial orientation performance. Our findings emphasize the role of spatial skills, notably spatial orientation, in mathematical development. The relation between spatial orientation and arithmetic was partially mediated by the number line estimation task. Our results further show that some aspects of spatial skills might be more predictive of mathematical development than others, underlining the importance to differentiate within the construct of spatial skills when it comes to understanding numerical development. [less ▲] Detailed reference viewed: 180 (46 UL)Mental arithmetic in the bilingual brain: Language matters. ; ; Guillaume, Mathieu et al in Neuropsychologia (2017), 101 How do bilinguals solve arithmetic problems in each of their languages? We investigated this question by exploring the neural substrates of mental arithmetic in bilinguals. Critically, our population was ... [more ▼] How do bilinguals solve arithmetic problems in each of their languages? We investigated this question by exploring the neural substrates of mental arithmetic in bilinguals. Critically, our population was composed of a homogeneous group of adults who were fluent in both of their instruction languages (i.e., German as first instruction language and French as second instruction language). Twenty bilinguals were scanned with fMRI (3T) while performing mental arithmetic. Both simple and complex problems were presented to disentangle memory retrieval occuring in very simple problems from arithmetic computation occuring in more complex problems. In simple additions, the left temporal regions were more activated in German than in French, whereas no brain regions showed additional activity in the reverse constrast. Complex additions revealed the reverse pattern, since the activations of regions for French surpassed the same computations in German and the extra regions were located predominantly in occipital regions. Our results thus highlight that highly proficient bilinguals rely on differential activation patterns to solve simple and complex additions in each of their languages, suggesting different solving procedures. The present study confirms the critical role of language in arithmetic problem solving and provides novel insights into how highly proficient bilinguals solve arithmetic problems. [less ▲] Detailed reference viewed: 172 (13 UL)LEARN Newsletter - Éditioun 2017: Multilinguisme Hoffmann, Danielle ; Hornung, Caroline ; Martin, Romain et al Book published by LEARN (2017) Detailed reference viewed: 56 (9 UL)How and Why Do Number-Space Associations Co-Vary in Implicit and Explicit Magnitude Processing Tasks? Georges, Carrie ; Hoffmann, Danielle ; Schiltz, Christine in Journal of Numerical Cognition (2017) Detailed reference viewed: 97 (9 UL)Different aspects of spatial skills and their relation to early mathematics Cornu, Véronique ; Hornung, Caroline ; Schiltz, Christine et al Poster (2016, September 29) We aimed at investigating the predictive role of spatial skills for arithmetic and number line estimation in kindergarten children (N = 125). Several studies highlighted the relation between spatial ... [more ▼] We aimed at investigating the predictive role of spatial skills for arithmetic and number line estimation in kindergarten children (N = 125). Several studies highlighted the relation between spatial skills and mathematics. However, due to their non-unitary nature, different aspects of spatial skills need to be differentiated to clarify the relative importance of different aspects of spatial skills for mathematics. In the present study, at time 1, a spatial perception task, a spatial visualization task and visuo-motor integration task were administered to assess different aspects of spatial skills. Furthermore we assessed domain-specific skills and verbal domain-general skills. Four months later, the same children performed an arithmetic task and a number line estimation task to evaluate how the abilities measured at time 1 predict early mathematics. Hierarchical regression modelling revealed that children’s performance on the spatial perception task was predictive of their performance in both arithmetic and number line estimation, whereas visuo-motor integration and knowledge of the Arabic numerals significantly predicted arithmetic. The predictive relation between spatial perception and arithmetic was partially mediated by the number line estimation task. Our findings emphasize the role of spatial skills, notably spatial perception, in mathematical development. These results reveal the importance to differentiate within the construct of spatial skills when studying their role in numerical development. The development and implementation of pre-school interventions fostering children’s spatial perception and visuo-motor integration might thus be a promising approach for providing children with a sound foundation for later mathematical learning. [less ▲] Detailed reference viewed: 180 (28 UL)How Math Anxiety relates to Number-Space Associations. Georges, Carrie ; Hoffmann, Danielle ; Schiltz, Christine in Frontiers in Psychology (2016), 7(1401), Given the considerable prevalence of math anxiety, it is important to identify the factors contributing to it in order to improve mathematical learning. Research on math anxiety typically focusses on the ... [more ▼] Given the considerable prevalence of math anxiety, it is important to identify the factors contributing to it in order to improve mathematical learning. Research on math anxiety typically focusses on the effects of more complex arithmetic skills. Recent evidence, however, suggests that deficits in basic numerical processing and spatial skills also constitute potential risk factors of math anxiety. Given these observations, we determined whether math anxiety also depends on the quality of spatial-numerical associations. Behavioral evidence for a tight link between numerical and spatial representations is given by the SNARC (spatial-numerical association of response codes) effect, characterized by faster left-/right-sided responses for small/large digits respectively in binary classification tasks. We compared the strength of the SNARC effect between high and low math anxious individuals using the classical parity judgment task in addition to evaluating their spatial skills, arithmetic performance, working memory and inhibitory control. Greater math anxiety was significantly associated with stronger spatio-numerical interactions. This finding adds to the recent evidence supporting a link between math anxiety and basic numerical abilities and strengthens the idea that certain characteristics of low-level number processing such as stronger number-space associations constitute a potential risk factor of math anxiety. [less ▲] Detailed reference viewed: 98 (10 UL)Age modulates the relation between number-space associations and arithmetical abilities in elementary school children Georges, Carrie ; Hoffmann, Danielle ; Schiltz, Christine Poster (2016, September) Evidence for number-space associations comes from the SNARC effect, consisting in faster RTs to small/large digits with the left/right hand respectively. In adults, number-space associations relate to ... [more ▼] Evidence for number-space associations comes from the SNARC effect, consisting in faster RTs to small/large digits with the left/right hand respectively. In adults, number-space associations relate to mathematical proficiency in that individuals with weaker arithmetic performances feature stronger SNARC effects (Hoffmann et al., 2014). However, in children far less is known about number-space associations and how they affect arithmetic performance. We therefore investigated the relationship between the classical parity SNARC effect and mathematical proficiency, assessed using the Heidelberger Rechentest, in elementary school children aged 8-11 years (n=55, mean=9.5). Overall, the parity SNARC regression slopes (-11.37, p<.001) negatively correlated with HRT arithmetical (r=-.28, p=.04; even when controlling for parity judgment RTs: r=-.37, p=.01), but not HRT visuo-spatial subscale scores (r=-.03, p=.82), indicating better arithmetic performances with stronger number-space associations. However, this relation was significantly moderated by age, since the interaction between the parity SNARC effect and age accounted for a significant proportion of the variance in HRT arithmetical scores (ΔR2=.07, b=0.26, t(51)=2.29, p=.03). A significant negative association was observed only in younger children (b=-0.35, t=-3.49, p=.001) aged below 9.5 years (n=29), while the SNARC effect did not relate to arithmetic performance in the remaining older children. This suggests that number-space associations are beneficial for arithmetic performance at relatively early stages of mathematical learning. During the course of mathematical development in childhood, number-space associations then turn superfluous for arithmetic achievement until they possibly become interfering in young adults, who have reached the peak of their developmental trajectory. [less ▲] Detailed reference viewed: 53 (6 UL)THE IMPACT OF LANGUAGE BACKGROUND ON BASIC MATH COMPETENCE Poncin, Alexandre ; ; Schiltz, Christine Poster (2016, April 02) German number word system inverts units and tens compared to the Arabic notation. This is not the case in French, which is more transparent regarding the Arabic number code. Evidence indicates that the ... [more ▼] German number word system inverts units and tens compared to the Arabic notation. This is not the case in French, which is more transparent regarding the Arabic number code. Evidence indicates that the linguistic structure of number words can facilitate or impede numerical development (Zuber, Pixner, & Moeller, 2009). Moreover, in transcoding tasks more mistakes are made in non-transparent compared to transparent languages (Imbo, Vanden Bulcke, De Brauwer, & Fias, 2014). We used a new paradigm of transcoding task in which 28 French-speaking (FR) and 19 German-speaking (GE) 4th grade children had to listen two digits numbers. The new thing was that we manipulate the order of appearance of the units and the tens of the number in three conditions: Units-First (UF), Tens-First (TF) and Simultaneous (S). Then, the subjects had to choose the heard number among four numbers presented on the computer screen. Results sows that GE are globally slower than FR (F(1,45) = 3.95, p = .053). The largest difference was observed for the TF: (t(45) = -3.729, p = .001). Moreover, when the order of the number appearance was congruent with the number word system, the transcoding was faster in both languages. For GE the S condition was slower than TF condition (F(2,36) = 6.918, p = .008) and than UF condition (F(2,36) = 6.918, p = .003.). For FR, the TF was faster than S (F(2,54) = 69.419, p < .001) and UF (F(2,54) = 69.419, p < .001). All these data indicate that language structure qualitatively impacts on basic numerical tasks. [less ▲] Detailed reference viewed: 53 (5 UL)THE IMPACT OF LANGUAGE BACKGROUND ON BASIC MATH COMPETENCE Poncin, Alexandre ; ; Schiltz, Christine Presentation (2016, February 18) German number word system inverts units and tens compared to the Arabic notation. This is not the case in French, which is more transparent regarding the Arabic number code. Evidence indicates that the ... [more ▼] German number word system inverts units and tens compared to the Arabic notation. This is not the case in French, which is more transparent regarding the Arabic number code. Evidence indicates that the linguistic structure of number words can facilitate or impede numerical development (Zuber, Pixner, & Moeller, 2009). Moreover, in transcoding tasks more mistakes are made in non-transparent compared to transparent languages (Imbo, Vanden Bulcke, De Brauwer, & Fias, 2014). We used a new paradigm of transcoding task in which 28 French-speaking (FR) and 19 German-speaking (GE) 4th grade children had to listen two digits numbers. The new thing was that we manipulate the order of appearance of the units and the tens of the number in three conditions: Units-First (UF), Tens-First (TF) and Simultaneous (S). Then, the subjects had to choose the heard number among four numbers presented on the computer screen. Results sows that GE are globally slower than FR (F(1,45) = 3.95, p = .053). The largest difference was observed for the TF: (t(45) = -3.729, p = .001). Moreover, when the order of the number appearance was congruent with the number word system, the transcoding was faster in both languages. For GE the S condition was slower than TF condition (F(2,36) = 6.918, p = .008) and than UF condition (F(2,36) = 6.918, p = .003.). For FR, the TF was faster than S (F(2,54) = 69.419, p < .001) and UF (F(2,54) = 69.419, p < .001). All these data indicate that language structure qualitatively impacts on basic numerical tasks. [less ▲] Detailed reference viewed: 26 (3 UL)Cardinal and ordinal processing in spatial neglect Sosson, Charlotte ; di Luca, Samuel ; Guillaume, Mathieu et al Poster (2016, January) Patients with spatial neglect do not only have difficulties in orienting attention in physical space but also in representational space, especially with respect to the mental representation of numbers ... [more ▼] Patients with spatial neglect do not only have difficulties in orienting attention in physical space but also in representational space, especially with respect to the mental representation of numbers. Indeed, in a study by Zorzi et al. (2012) neglect patients were particularly slow when asked to compare the number 4 to the standard number 5, suggesting difficulties to process numbers on the left side of an internal standard. This difficulty was observed in a magnitude judgement, but not in a parity task, implying a dissociation between explicit and implicit processing of numerical magnitude. The present study aimed at replicating these findings and extending them to non-numerical sequences in order to complement the data obtained on bisection tasks (Zamarian, et al., 2007). Sixteen right-sided brain damaged patients with neglect (N+ =6; 4 females; all right handers; mean age: 55 +/- 8,7) and without neglect (N- =10; 2 females; all right hander; mean age: 48 +/- 6.2) participated in the study. They were administered the following tasks: a magnitude and a parity judgement task; an ordinal judgement task on numbers and on letters and a consonant/vowel classification task. For each task and each patient, a linear regression was computed in which the difference between the response times for the left effector (index finger) and the right effector (middle finger) was predicted by number magnitude. A negative slope will indicate the presence of a SNARC-like effect. We compared the negative slopes of the two patient groups using a Chi-square. Considering the proportion of SNARC-like effects, it appeared that, on one hand, N+ patients showed fewer SNARC-like effects than N- patients during magnitude judgements on numbers. Thus confirming the findings by Zorzi et al. (2012). On the other hand, N+ patients behaved similarly to N- patients for the parity judgements on numbers and for the order judgements both on numbers and letters. This last result suggest a dissociation between the spatial representation of magnitude and of order in N+ patients. These results point towards a specific impairment in explicit access to number magnitude in spatial hemineglect. [less ▲] Detailed reference viewed: 89 (14 UL)Solving arithmetic problems in first and second language: Does the language context matter? Van Rinsveld, Amandine ; Schiltz, Christine ; et al in Learning and instruction (2016) Learning mathematics in a second language is a challenge for many learners. The purpose of the study was to provide new insights into the role of the language context in mathematic learning and more ... [more ▼] Learning mathematics in a second language is a challenge for many learners. The purpose of the study was to provide new insights into the role of the language context in mathematic learning and more particularly arithmetic problem solving. We investigated this question in a GermaneFrench bilingual educational setting in Luxembourg. Participants with increasing bilingual proficiency levels were invited to solve additions in both their first and second instruction languages: German and French. Arithmetic problems were presented in two different conditions: preceded by a semantic judgment or without additional language context. In the French session we observed that additions were systematically performed faster in the condition with an additional language context. In contrast no effect of the context was observed in the German session. In conclusion, providing a language context enhanced arithmetic performances in bilinguals' second instruction language. This finding entails implications for designing optimal mathematic learning environments in multilingual educational settings. [less ▲] Detailed reference viewed: 223 (24 UL)Math anxiety is predicted by the strength of number-space associations, over and beyond arithmetic ability and WM Georges, Carrie ; Hoffmann, Danielle ; Schiltz, Christine Poster (2015, October) Math skills are undeniably important in everyday life. Math anxiety can, however, threaten their optimal development. Given that a fifth of the population experiences high math anxiety, it is important to ... [more ▼] Math skills are undeniably important in everyday life. Math anxiety can, however, threaten their optimal development. Given that a fifth of the population experiences high math anxiety, it is important to identify its origins in order to improve mathematical learning. Research on math anxiety typically focusses on the effects of math ability, WM, and spatial performance. Recent evidence, however, suggests that it also depends on basic numerical processes, with high math anxious individuals featuring less precise numerical representations, as indexed by stronger distance effects. Another marker for the nature of numerical representations is the SNARC effect, alluding to their spatial organization. Although number-space associations depend on WM, spatial performance and arithmetic ability - all related to math anxiety - their relationship with the latter has never been tested. We thus determined whether math anxiety is related to the strength of number-space associations. All participants (n=60, 28 female) completed the r-MARS, the parity judgment, an arithmetic, and visuospatial WM task. We replicated previous findings on the negative relationships between math anxiety and arithmetic ability (r=-0.3, p=0.02), and WM (r=-0.29, p=0.03). But most importantly, we found a significant negative correlation between the SNARC effect and math anxiety (slope=-11.42, r=-0.43, p<0.001), with high math anxious individuals featuring greater interference of the irrelevant magnitude-associated spatial code. Interestingly, number-space associations were the only significant predictor of math anxiety in a multiple regression analysis. Our findings thus provide further evidence for the association between numerical representations and math anxiety, over and beyond arithmetic ability and WM. [less ▲] Detailed reference viewed: 88 (10 UL) |
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