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See detailEl Estado de Bienestar de la 4T y La Tercera Vía
Huitrón García, Patricia Manuela; Cebotari, Victor UL; Rodríguez Rosario, David Gustavo

Article for general public (2021)

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See detailINVESTIGATING T CELLS IN THE CONTEXT OF NEUROIMMUNOLOGY: MOLECULAR AND CELLULAR MECHANISMS DURING A STRESS RESPONSE AND A PATIENT-BASED STUDY IN PARKINSON'S DISEASE
Capelle, Christophe Michael UL

Doctoral thesis (2021)

For a long time, the nervous system and the immune system have been studied as isolated entities, but a growing body of evidence shows that there is an extensive crosstalk between both systems. In fact ... [more ▼]

For a long time, the nervous system and the immune system have been studied as isolated entities, but a growing body of evidence shows that there is an extensive crosstalk between both systems. In fact, neurons and immune cells share certain functional features and reside in close proximity within the tissues, enabling them to effectively communicate. T cells are crucial for mounting and controlling almost any kind of immune response. However, when dysregulated, T cells fail to protect the host from invading pathogens or can cause damage to surrounding tissues, leading to autoimmunity-related pathology. In the first part of this cumulative thesis, we aimed at identifying novel genes regulating CD4 T cell responses and identified VIMP, one of the 25 human proteins containing the 21st amino acid selenocysteine, as a gene having anti-inflammatory functions. Furthermore, T cells express various neurotransmitter receptors allowing the integration of neuronal signal for an appropriate response. In the second part, we showed a CD4-T-cell-intrinsic mechanism through which stress hormones mediate their control over the immune system. We identified a previously unrecognized pathway regulating CD4 T cell differentiation that involves the circadian clock gene Per1 and mTORC1 signalling. Finaly, T cells involvement in different neuropathologies has been reported in the past few decades. Emerging evidence indicates the involvement of the immune system and in particular T cells in the pathogenesis of Parkinson’s disease (PD), the 2nd most common neurodegenerative disease. In the 3rd part of the thesis we systematically characterized the immunological status of early-to-mid stage PD patients and matched healthy controls, and identified a distinct peripheral immunological fingerprint in PD patients, especially in the CD8 T-cell compartment. The findings of the studies described in this cumulative thesis advance our understanding of the regulatory nodes of CD4 T cells during a stress response and fill the knowledge gap on the early involvement of CD8 T cells and other immune subsets in neurodegenerative diseases in the case of PD. [less ▲]

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See detailAre Firms Withdrawing From Basic Research? An Analysis of Firm-level Publication Behaviour in Germany
Krieger, Bastian UL; Blind, Knut; Gruber, Sonia et al

in Scientometrics (2021), 126

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See detailPerformance assessment of the relative gravimeter Scintrex CG-6
Francis, Olivier UL

in Journal of Geodesy (2021), 95:116

The new-generation relative gravimeter Scintrex CG6 is put on the test bench: Its performance is compared to its predecessor, the Scintrex-CG5. A CG5 Scintrex and a CG6 Scintrex were both submitted to the ... [more ▼]

The new-generation relative gravimeter Scintrex CG6 is put on the test bench: Its performance is compared to its predecessor, the Scintrex-CG5. A CG5 Scintrex and a CG6 Scintrex were both submitted to the same rigorous tests, which have been developed in recent years to highlight some defects of the CG5. The results show that the CG6 always performs better than the CG5. For instance, the instrumental drift is 5 times smaller for the CG6 than for the CG5. In the tidal bands, the noise level of the CG6 is 3 times lower than of the one of the CG5. We confirmed the tilt susceptibility of the CG5 and found that the CG6 is barely affected by long duration tilts before taking measurements. Unlike the CG5, the CG6 measurements are not influenced by external temperature variations. Overall, the CG6 provides more precise and stable gravity measurements compared to the CG5. [less ▲]

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See detailPeut beaucoup mieux faire:Les stéréotypes de genre dans les manuels de l’enseignement fondamental
Quiqueret, Jérôme; Kerger, Sylvie UL

Article for general public (2021)

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See detailSpinning Functional Fibers: An Interplay of Rheology, Miscibility & Crosslinking
Vats, Shameek UL

Doctoral thesis (2021)

Wearable technology in general has increasingly gained interest in the last few decades and textile with incorporated functional component constitute one form of it. There are multiple ways to produce ... [more ▼]

Wearable technology in general has increasingly gained interest in the last few decades and textile with incorporated functional component constitute one form of it. There are multiple ways to produce polymer fibers on both laboratory and industrial scales, and one of them is core–sheath electrospinning, which is a powerful method for producing advanced composite fibers. Liquid crystals (LCs), are materials that readily exhibit optical response to fluctua- tions and change in their immediate environment. By incorporating LC within polymer fibers through electrospinning, it is possible to create responsive LC-polymer fiber mats. However, incorporating a functional core has proven challenging for certain combinations of materials. This thesis explores and addresses some of the concerns involved in the coaxial electrospinning of fibers incorporating LCs from several standpoints. Firstly, the effect of solvents on the electrospinning process was systematically studied. Fol- lowing this, an optimum viscosity with pure and mixed solvents for successful electrospinning was identified and uniform fibers with different solvent combinations was produced. Using the knowledge gained, core-sheath electrospinning with LC as the core was carried out. One of the key findings of this work, the identification of a suitable means to reduce the interfacial tension between the core and sheath fluid to prevent break up of the jet and produce uniformly filled fibers, while at the same time avoiding complete mixing between core and sheath. These findings can be applied to any combination of core and sheath materials and should appeal to a large community of researchers. Eventually, to achieve the durability of the LC-functionalized electrospun fiber mats for use in wearable technology, the sheath polymer of the fiber were crosslinked after spinning. The resultant crosslinked fibers were easily manipulated by hand and even fully immersed in water without dissolving and without losing their functional LC core. [less ▲]

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See detailLeveraging High-Frequency Components for Deepfake Detection
Mejri, Nesryne UL; Papadopoulos, Konstantinos UL; Aouada, Djamila UL

in IEEE Workshop on Multimedia Signal Processing (2021)

In the past years, RGB-based deepfake detection has shown notable progress thanks to the development of effective deep neural networks. However, the performance of deepfake detectors remains primarily ... [more ▼]

In the past years, RGB-based deepfake detection has shown notable progress thanks to the development of effective deep neural networks. However, the performance of deepfake detectors remains primarily dependent on the quality of the forged content and the level of artifacts introduced by the forgery method. To detect these artifacts, it is often necessary to separate and analyze the frequency components of an image. In this context, we propose to utilize the high-frequency components of color images by introducing an end-to-end trainable module that (a) extracts features from high-frequency components and (b) fuses them with the features of the RGB input. The module not only exploits the high-frequency anomalies present in manipulated images but also can be used with most RGB-based deepfake detectors. Experimental results show that the proposed approach boosts the performance of state-of-the-art networks, such as XceptionNet and EfficientNet, on a challenging deepfake dataset. [less ▲]

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See detailCyborg, IA et société "cyborgisée" : l’avènement d’une société-ruche
Derian, Maxime UL

in Collectif (Ed.) Aux frontières de l'humain (2021)

If the cyborg remains a human - repaired, augmented or diminished -, the emergence of metaphorical or real figures such as the latter as well as hybrids, robots, drones and AIs, is perhaps the expression ... [more ▼]

If the cyborg remains a human - repaired, augmented or diminished -, the emergence of metaphorical or real figures such as the latter as well as hybrids, robots, drones and AIs, is perhaps the expression of an anthropological major shift. Indeed, beyond the question of the enhanced humanity, transhumanism and the possibility of posthumanism, it seems topical to ask whether it is not society itself that is in the process of becoming 'cyborgised' on a global scale. In such a case, rather than listing the anthropotechnical technologies (of human modification) that have appeared since the invention of computers, it seems appropriate to anticipate and attempt to understand the ethical, political, economic and social issues emblematic of these technologies. Hence the concept of the 'hive-society', used to describe this possible major break in history marked by the advent of an organisation that is above all administered by - and sometimes for - digital machines. [less ▲]

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See detailMendelian randomization study of smoking, alcohol, and coffee drinking in relation to Parkinso's disease
Domenighetti, Cloe; Sugier, Pierre Emmanuel; Sreelatha, Ashwin Ashok Kumar et al

in Journal of Parkinson's Disease (2021)

Background:Previous studies showed that lifestyle behaviors (cigarette smoking, alcohol, coffee) are inversely associated with Parkinson’s disease (PD). The prodromal phase of PD raises the possibility ... [more ▼]

Background:Previous studies showed that lifestyle behaviors (cigarette smoking, alcohol, coffee) are inversely associated with Parkinson’s disease (PD). The prodromal phase of PD raises the possibility that these associations may be explained by reverse causation. Objective:To examine associations of lifestyle behaviors with PD using two-sample Mendelian randomisation (MR) and the potential for survival and incidence-prevalence biases. Methods:We used summary statistics from publicly available studies to estimate the association of genetic polymorphisms with lifestyle behaviors, and from Courage-PD (7,369 cases, 7,018 controls; European ancestry) to estimate the association of these variants with PD. We used the inverse-variance weighted method to compute odds ratios (ORIVW) of PD and 95%confidence intervals (CI). Significance was determined using a Bonferroni-corrected significance threshold (p = 0.017). Results:We found a significant inverse association between smoking initiation and PD (ORIVW per 1-SD increase in the prevalence of ever smoking = 0.74, 95%CI = 0.60–0.93, p = 0.009) without significant directional pleiotropy. Associations in participants ≤67 years old and cases with disease duration ≤7 years were of a similar size. No significant associations were observed for alcohol and coffee drinking. In reverse MR, genetic liability toward PD was not associated with smoking or coffee drinking but was positively associated with alcohol drinking. Conclusion:Our findings are in favor of an inverse association between smoking and PD that is not explained by reverse causation, confounding, and survival or incidence-prevalence biases. Genetic liability toward PD was positively associated with alcohol drinking. Conclusions on the association of alcohol and coffee drinking with PD are hampered by insufficient statistical power. [less ▲]

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See detailAdvanced Characterizations of Silica Surface in Rubber Compounds by Solid-State Nuclear Magnetic Resonance Spectroscopy
Yan, Chuanyu UL

Doctoral thesis (2021)

This thesis details the development, validation, and application of advanced solid-state nuclear Magnetic resonance spectroscopy (NMR) techniques for the characterization of the silica surface in raw ... [more ▼]

This thesis details the development, validation, and application of advanced solid-state nuclear Magnetic resonance spectroscopy (NMR) techniques for the characterization of the silica surface in raw materials and in rubber compounds. The performance of the quantitative techniques (29Si DP-CPMG, SVD and 29Si multiCP) and qualitative techniques (29Si CP-CPMG and {1H-29Si}-1H MCPi) are investigated using model and close-to-real life samples. The insights gained from this study are useful for the surface-specific characterization of silica and could offer clues for similar topics. [less ▲]

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See detailExploring the Past in Public: Recent Public History Exchanges in Southern Luxembourg
Harnoncourt, Julia UL; van de Maele, Jens UL

Scientific Conference (2021, October 07)

Detailed reference viewed: 38 (2 UL)
See detailL’UEBL et les relations belgo-luxembourgeoises au XXème siècle
Brüll, Christoph UL

Scientific Conference (2021, October 06)

Detailed reference viewed: 39 (0 UL)
See detailSix provocations for 6G
Schafer, Valerie UL

Scientific Conference (2021, October 06)

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See detailA Distributed Unmanned Aerial Vehicles Traffic Management System
Samir Labib, Nader UL

Doctoral thesis (2021)

The rapid adoption of Internet of Things (IoT) has encouraged the integration of new connected platforms such as Unmanned Aerial Vehicles (UAVs) to the ubiquitous network. UAVs promise a pragmatic ... [more ▼]

The rapid adoption of Internet of Things (IoT) has encouraged the integration of new connected platforms such as Unmanned Aerial Vehicles (UAVs) to the ubiquitous network. UAVs promise a pragmatic solution to the limitations of existing terrestrial IoT infrastructure as well as they bring new means of delivering services through a wide range of applications ranging from monitoring and surveillance to on-demand last-mile delivery and people transport. Owning to their potential, UAVs are expected to soon dominate the low-altitude airspace over populated cities. This introduces new research challenges such as the safe management of UAVs operation under high traffic demands. In response to this, industry proposed a handful of constructs for UAV Traffic Management (UTM), however due to their centralised approaches, they will inevitably face limitations in scalability and resilience with predicted traffic demands and advancement in UAV autonomy. In this context, the main objective of this work is to address the aforementioned problem by proposing a distributed UAV Traffic Management system (dUTM). This thesis, hence, investigates the validity of the above hypothesis by: (i) showing the performance insufficiency of centralised systems due to their inadequacy in efficiently optimising large UAV traffic, (ii) showing why a distributed system is favourable due to its characteristics of scalability and resilience, (iii) proposing a novel dUTM framework consisting of an airspace structure model, information exchange model and a traffic optimisation model that rely on distributed methods and approaches to intelligently handle highly dynamic and challenging traffic conditions. To this end, this manuscript contributes to scientific literature by proposing a novel way of structuring the uncontrolled, low-altitude airspace and introduces a model of the Class G airspace as a multi-weighted multilayer network of nodes and airways. Additionally the work presents a novel distributed multiobjective path planning algorithm incorporating a dynamic multi-criteria decision matrix allowing each UAV or agent to plan their path relying on local knowledge gained via digital stigmergy. The PhD thesis additionally contributes to existing state of the art by exploring the technical standardisation landscape and investigating synergies between research directions and standards developments, taking into consideration pressing inherit challenges of UAVs within IoT such as security, data protection and privacy. [less ▲]

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See detailCareer journeys of skilled migrants in Luxembourg: a qualitative exploration
Usanova, Ksenia UL

Scientific Conference (2021, October 05)

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See detailLinking urban landscapes to ecosystem services and carbon flows: A European analysis.
Boura, Marlène Delphine Fabienne UL

Doctoral thesis (2021)

In the context of population growth and urbanisation, associated with an increase in the concentration of GHG (greenhouse gases) in the atmosphere, the impact of human activities on climate change is ever ... [more ▼]

In the context of population growth and urbanisation, associated with an increase in the concentration of GHG (greenhouse gases) in the atmosphere, the impact of human activities on climate change is ever increasing. Simultaneously, the pressure on natural ecosystems, especially in and around cities, is intensifying. Natural ecosystems associated with the urban forest (all elements of urban vegetation) can play an important role in mitigating climate change, especially in cities. In addition, they can contribute positively to the quality of life and wellbeing of urban dwellers. The dynamic of the services they provide, to Earth and mankind, vary between and within cities and need to be better understood. This thesis focusses on the impact of the spatial integration of the urban forest on the supply and demand of ecosystem services. The main objective is to provide insights into how urban forms and their inner characteristics are related to ecosystem services (ES) and to carbon dioxide (CO2) profiles. In particular, it analyses the level of integration of the urban forest present within the built up footprint and anthropogenic land, in order to derive the effect of their spatial distribution on 5 ES provided by the urban forest. The research is conducted at detailed spatial resolution for hundreds of Functional Urban Areas (FUAs) in Europe. It is structured as follows. We built an Urban Forest typology for Europe: 689 urban areas in 10 clusters and gathered in 4 groups (Forest cities, Herbaceous cities, Anthropogenic cities and Standard European cities). The typology reveals how nature is spatially integrated into urban structures. The metrics used in the typology reflect the potential supply and demand of 5 urban ES associated with the urban forest: micro climate regulation, macro climate regulation, air quality regulation, rainwater runoff regulation and physical and mental health. All cities are ranked according to an overall score. One of our main conclusions is that, given the same forest cover, a spatially integrated urban forest makes cities less sensitive to urban stressors. We then focus on a specific regulatory ES: macro climate regulation. The Urban Carbon Balance (UCB) model has been developed and allows the estimation of the urban carbon balance at a high spatial and temporal resolution for a large number of areas, using land used and emission data. The UCB model has been applied to 802 European urban areas. We downscaled anthropogenic CO2 emissions to a spatial resolution of 1 ha before applying a temporal decomposition of annual, monthly and finally daily emissions, following year-, sector- and country-specific guidelines. For a typical day of each month, we simulate 3 steady-state situations for the dispersion and sequestration of CO2 molecules. We find that the urban structure and the level of integration of the urban forest contribute positively to helping urban areas sequester their own emissions. [less ▲]

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See detailAutomatic Analysis, Representation and Reconstruction of Textured 3D Human Scans
Saint, Alexandre Fabian A UL

Doctoral thesis (2021)

Various practical applications in computer vision are related to the human body. These involve representing and modelling the body shape, pose, clothing and appearance with mathematical and statistical ... [more ▼]

Various practical applications in computer vision are related to the human body. These involve representing and modelling the body shape, pose, clothing and appearance with mathematical and statistical tools requiring datasets of examples, representative of the variation in the data. Three-dimensional (3D) data is especially important as it allows to simulate the physical world directly, for example to analyse and lift ambiguities in other prevalent data modalities, such as images. However, existing datasets of 3D human scans show limitations in their size, diversity, quality or annotation. This reduces their applicability in tackling research questions around the 3D human body. Two particular applications of interest that remain unanswered are the estimation of body shape under clothing, and the completion of textured shape of missing or defective data. This thesis proposes three main contributions. First, 3DBodyTex, a dataset of 3D human scans, which complements alternative datasets with real scans, body and clothing scans, hundreds of subjects, high-resolution texture information, dense annotations and aligned body shapes under the clothing. The aim is to enable and facilitate new research possibilities with learning-based methods, in 3D or using derived modalities. Second, to build this dataset automatically from raw scans, multiple robust 3D processing methods are proposed. These involve pose estimation, pose fitting, tight body shape fitting, and body shape estimation under clothing. The proposed methods show competitive or improved results on existing benchmarks and new proposed benchmarks based on 3DBodyTex. In particular, an alternative method is proposed to estimate the body shape under clothing from a single scan. On independent benchmarks, it is competitive with, or better than, methods requiring a full time sequence of scans. Third, the task of shape and texture completion of 3D human scans is tackled. A new method is proposed that completes the shape and the texture sequentially, and automatically identifies the missing regions. In particular, partial convolutions are extended to texture images (UV maps) for inpainting the colour of a 3D scan using a convolutional neural network. A new benchmark, based on 3DBodyTex, is proposed for the evaluation. [less ▲]

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See detailDigital Identities and Verifiable Credentials
Sedlmeir, Johannes UL; Smethurst, Reilly UL; Rieger, Alexander UL et al

in Business and Information Systems Engineering (2021), 63(5), 603-613

Public institutions and companies typically employ physical credentials (such as passports, social security cards, and employee badges) to identify individuals. Individuals can choose where to store their ... [more ▼]

Public institutions and companies typically employ physical credentials (such as passports, social security cards, and employee badges) to identify individuals. Individuals can choose where to store their physical credentials, and sometimes, they can decide to whom their credentials are disclosed. These familiar privileges inspired a new type of digital credential called a verifiable credential (VC). Similar to physical credentials, individuals can store their verifiable credentials in a so-called digital wallet on their mobile phone, on another edge device, or in the cloud, and they can use verifiable credentials for identification, authentication, and authorization. [less ▲]

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See detailSPON: Enabling Resilient Inter-Ledgers Payments with an Intrusion-Tolerant Overlay
Trestioreanu, Lucian Andrei UL; Nita-Rotaru, Cristina; Malhotra, Aanchal et al

Scientific Conference (2021, October 04)

Payment systems are a critical component of everyday life in our society. While in many situations payments are still slow, opaque, siloed, expensive or even fail, users expect them to be fast ... [more ▼]

Payment systems are a critical component of everyday life in our society. While in many situations payments are still slow, opaque, siloed, expensive or even fail, users expect them to be fast, transparent, cheap, reliable and global. Recent technologies such as distributed ledgers create opportunities for near-real-time, cheaper and more transparent payments. However, in order to achieve a global payment system, payments should be possible not only within one ledger, but also across different ledgers and geographies.In this paper we propose Secure Payments with Overlay Networks (SPON), a service that enables global payments across multiple ledgers by combining the transaction exchange provided by the Interledger protocol with an intrusion-tolerant overlay of relay nodes to achieve (1) improved payment latency, (2) fault-tolerance to benign failures such as node failures and network partitions, and (3) resilience to BGP hijacking attacks. We discuss the design goals and present an implementation based on the Interledger protocol and Spines overlay network. We analyze the resilience of SPON and demonstrate through experimental evaluation that it is able to improve payment latency, recover from path outages, withstand network partition attacks, and disseminate payments fairly across multiple ledgers. We also show how SPON can be deployed to make the communication between different ledgers resilient to BGP hijacking attacks. [less ▲]

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See detailEmergent Multilingual Children's Agency within Translanguaging Practices with Peers and Practitioners in Formal and Non-formal Early Childhood Education Settings in Luxembourg
Mortini, Simone UL

Doctoral thesis (2021)

In our increasingly globalised, heterogenous and varied societies, scholars have called for multilingual pedagogies that build on this diversity as a resource and promote flexible language practices to ... [more ▼]

In our increasingly globalised, heterogenous and varied societies, scholars have called for multilingual pedagogies that build on this diversity as a resource and promote flexible language practices to facilitate children’s participation and language appropriation or learning. Nevertheless, the existing literature on young children’s own capacities to act in light of these innovative and inclusive pedagogies remains scarce, particularly in multilingual contexts involving more than two named languages. This thesis presents a longitudinal qualitative study of young emergent multilingual children’s agency within translanguaging practices when appropriating new language features in early childhood education in multilingual Luxembourg. Guided by a sociocultural framework and a translanguaging lens, the study investigates the ways in which emergent multilingual children engage in translanguaging practices and thereby practise different forms of agency in interaction with peers and practitioners. The data stems from eight focal children, aged three to five, in two formal and two non-formal early childhood education settings. The qualitative data was collected over eleven months in 2016 and 2017, combining observations, fieldnotes, and video-recordings, as well as informal discussions and semi-structured interviews with the practitioners. The data analysis consisted of analysing recurring patterns and differences in the children’s deployment of their entire semiotic repertoires, conducting a micro-analysis of the children’s interactions with peers and practitioners as well as triangulating the data and the methods. The results revealed that the focal children were particularly active when appropriating new language features and shaped the language practices of their peers and the practitioners. The children thereby practised agency on two levels. Firstly, they did not passively reproduce the practices and languaging of the adults, but instead creatively transformed and implemented the practitioners’ (trans)languaging activities, practices and interaction patterns in their peer culture. Secondly, they showed language-based agentic behaviour on a continuum from participatory to controlling behaviour, during interactions with both their peers and the practitioners. While the participatory agency consisted of showing creative language-based agentic behaviour under the control of the practitioners, the controlling agency went beyond mere participation and related to children taking choices in language use and actively shaping the language use of their peers and the practitioners. These findings may be particularly relevant to understanding the language practices and agency of young emergent multilingual children when they encounter new languages in early childhood education – in particular, as the children’s languaging and agency depended on the pedagogy and the practitioners’ language-supportive strategies. One important outcome of the study is the provision of recommendations for practitioners and policymakers wishing to capitalise on children’s rich and varied semiotic resources. The study is moreover of interest to researchers and students in the fields of early childhood education, language learning and multilingual education. [less ▲]

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