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It has long been known that tissue non-specific alkaline phosphatase (TNAP) is essential for the correct formation of bone, as altered expression or function of this enzyme results in hypophosphatasia, a disease characterised by compromised bone structure, density and strength. However, recent evidence strongly suggests that the enzyme also has a role in lipid accrual and adipogenesis, a function that seems far removed from bone formation. Given that mesenchymal stromal cells (MSCs) are progenitors of both osteoblasts and adipocytes, the question arises of how TNAP is regulated to potentially have a different function when MSCs undergo either osteogenesis or adipogenesis. As the primary protein sequence is unchanged for the enzyme during both types of differentiation, any differences in function must be attributed to post-translational modification and/or localisation. We therefore examined the location of TNAP in bone- or adipose-derived MSCs differentiated into an adipocytic phenotype and compared the glycosylation state of the enzyme in MSCs differentiated into either osteoblasts or adipocytes. TNAP was found to co-locate with perilipin around lipid droplets in MSCs from bone, subcutaneous- and visceral adipose tissue during adipocytic differentiation. Treatment of TNAP with wheat germ lectin followed by electrophoresis showed minor differences in glycosylation between the phosphatase isolated from cells from these tissues, whereas electrophoresis after neuraminidase digestion highlighted differential glycosylation between cell types and during adipogenesis and osteoblastogenesis. This infers that post-translational modification of TNAP is altered during differentiation and is dependent on the eventual phenotype of the cells.

Tissue-nonspecific alkaline phosphatase (TNAP) is one of four isozymes, which include germ cell, placental and intestinal alkaline phosphatases. The TNAP isozyme has 3 isoforms (liver, bone and kidney) which differ by tissue expression and glycosylation pattern. Despite a long history of investigation, the exact function of TNAP in many tissues is largely unknown. Only the bone isoform has been well characterised during mineralization where the enzyme hydrolyses pyrophosphate to inorganic phosphate, which combines with calcium to form hydroxyapatite crystals deposited as new bone. The inorganic phosphate also increases gene expression of proteins that support tissue mineralization. Recent studies have shown that TNAP is expressed in preadipocytes from several species, and that inhibition of TNAP activity causes attenuation of intracellular lipid accumulation in these and other lipid-storing cells. The mechanism by which TNAP stimulates lipid accumulation is not known; however, proteins that are important for controlling phosphate levels in bone are also expressed in adipocytes. This review examines the evidence that inorganic phosphate generated by TNAP promotes transcription that enhances the expression of the regulators of lipid storage and consequently, that TNAP has a major function of lipid metabolism.

Scholarship on translanguaging and related concepts has challenged traditional assumptions about how people use their multiple languages, urging us to move beyond the boundaries of named linguistic codes and toward conceptualizations of multilingual language use as flexible use of a speaker’s whole linguistic repertoire. Critiques of this theoretical shift have included assertions of translanguaging’s conceptual and practical limits—limits to its transformative potential as well as limits to its practical use. This paper takes up, in particular, the question of why we academics may assert the value of translanguaging in schools and communities while still largely failing to move beyond monoglossic English norms in our own academic spaces of professional practice (Jaspers, 2018), especially in the dissemination of research. Acknowledging this hegemony as well as its potential disruption, we present a counterexample of an academic research conference that developed as a trilingual, translingual space unlike most other spaces of research dissemination. In this polyvocal, translingual reflection, we describe and analyze the event from the perspectives of conference organizers, keynote speakers, and attendees. We explore the factors that constituted the transformative nature of the conference’s translanguaging space and offer some preliminary principles of language planning for translingual academic spaces.

International education policy makers, donors, and implementers have heavily emphasized correct words per minute (CWPM) to measure reading intervention impact. While fluency integrates accuracy, au...

Comparison is a valuable and widely touted analytical technique in social research, but different disciplines and fields have markedly different notions of comparison. There are at least two important logics for comparison. The first, the logic of juxtaposition, is guided by a neopositivist orientation. It uses a regularity theory of causation; it structures the study by defining cases, variables, and units of analysis a priori; and it decontextualizes knowledge. The second, the logic of tracing, engages a realist theory of causation and examines how processes unfold, influenced by actors and the meanings they make, over time, in different locations, and at different scales. These two logics of comparison lead to distinct methodological techniques. However, with either logic of comparison, three dangers merit attention: decontextualization, commensurability, and ethnocentrism. One promising research heuristic that attends to different logics of comparison while avoiding these dangers is the comparative case study (CCS) approach. CCS entails three axes of comparison. The horizontal axis encourages comparison of how similar policies and practices unfold across sites at roughly the same level or scale, for example across a set of schools or across home, school, religious institution, and community organization. The vertical axis urges comparison across micro-, meso-, and macro-levels or scales. For example, a study of bilingual education in the United States should attend not only to homes, communities, classroom, and school dynamics (the micro-level), but also to meso-level district, state, and federal policies, as well as to factors influencing international mobility at the macro-level. Finally, the transversal axis, which emphasizes change over time, urges scholars to situate historically the processes or relations under consideration.

This article examines students’ experiences as resettled refugee and asylee students in international schools in New York City. Specifically, it looks at how teachers and school leaders provide cri...

As the number of refugee children and youth across the world continues to grow at an alarming rate, the needs of refugee populations require more and sustained attention. This qualitative study explores the specific academic and socio-emotional needs of refugee students in New York City (NYC), a city that has received refugees and asylum seekers from over 50 countries. Using qualitative research methods and drawing on the literature on refugee students’ school experiences and acculturation theory, in this article we ask how refugee students describe the key features of international high schools that foster students’ academic success, social and cultural integration, and academic well-being. Moreover, we examine how the notion of culture itself can interfere with these efforts.

Foreword to the Thematic Section – Methods of Comparative Education Apresentação da Seção Temática – Métodos de Educação Comparada

Case studies in the field of education often eschew comparison. However, when scholars forego comparison, they are missing an important opportunity to bolster case studies’ theoretical generalizability. Scholars must examine how disparate epistemologies lead to distinct kinds of qualitative research and different notions of comparison. Expanded notions of comparison include not only the usual logic of contrast or juxtaposition but also a logic of tracing, in order to embrace approaches to comparison that are coherent with critical, constructivist, and interpretive qualitative traditions. Finally, comparative case study researchers consider three axes of comparison: the vertical, which pays attention across levels or scales, from the local through the regional, state, federal, and global; the horizontal, which examines how similar phenomena or policies unfold in distinct locations that are socially produced; and the transversal, which compares over time.

This article explores the curricular approaches of three public high schools in the US that serve newly arrived immigrant and refugee youth, in order to define and illustrate a critical transnation...

This qualitative study examines how an “international” high school in New York City responds to the needs of refugee students. It asks: What are the specific academic needs of secondary-level refugee students? How does one school meet their needs, and what challenges are encountered? To complement one-on-one semi-structured interviews and focus group discussions, this qualitative study also entailed a participatory visual methodology through which students were provided digital or disposable cameras and asked to take photographs of the people, places and/or things that contributed to their schooling experiences. The exercise and resulting images provided students and researchers with a creative way to shape the project and address emerging issues. The findings document key school-based factors that contribute to academic inclusion of refugee and asylee students, including: educator support, care and encouragement; linguistic support from teachers; learner-centered pedagogical approaches; and flexible and responsive curricular approaches and assessment strategies. Refugees are generally grouped with other immigrants, with insufficient attention to their unique experiences and needs and thus inadequate services for refugee children. The findings from this study will help to remedy this gap and yield important insights regarding how to improve schooling for vulnerable populations in urban settings.

This paper examines how a transnational orientation shapes Dominican mothers’ contradictory attitudes towards education in New York City. Through this ethnographic study, which draws on 36 interviews, community walkabouts, and participant observations in community-led adult education classes, we show how Dominican mothers struggle with conflicting values; on the one hand, they embrace the idea of schooling for individual advancement, integration in the US, and critical thinking, while on the other hand, they regret the diminution of a collective, family orientation and respect for parents. Overall, this study shows that contradictions are not a sign of confusion or denial, but rather a struggle to transform cultural practices that satisfy multiple worlds. A deeper understanding of these contradictions could help educators and educational institutions consider how these transnational tensions motivate parent engagement and their hopes for their children’s education.

Learning has emerged as a central theme within post-2015 debates. Central to these efforts have been a focus on literacy, and specifically early grade reading. This article identifies significant challenges raised by the current framing of emergent literacy in international educational development circles. Specifically, we examine how the Early Grade Reading Assessment, or EGRA, one very influential oral reading assessment tool based largely on an American reading assessment called DIBELs, has shaped the educational quality debate in the past decade and what important elements might be missing from this dominant view of reading. To do so, the article first considers the historical development of EGRA. We discuss concerns with the model of reading embedded in EGRA. We then examine the evidence, to date, of the impact of EGRA-informed interventions in places like Liberia, Malawi, and Kenya. The article concludes with implications for the future of literacy and international educational development, especially in light of discussions within the Learning Metrics Task Force to make early grade reading a central indicator of educational quality in the post-2015 agenda.

What is a case study and what is it good for? In this article, we argue for a new approach—the comparative case study approach—that attends simultaneously to macro, meso, and micro dimensions of case-based research. The approach engages two logics of comparison: first, the more common compare and contrast; and second, a ‘tracing across’ sites or scales. As we explicate our approach, we also contrast it to traditional case study research. We contend that new approaches are necessitated by conceptual shifts in the social sciences, specifically in relation to culture, context, space, place, and comparison itself. We propose that comparative case studies should attend to three axes: horizontal, vertical, and transversal comparison. We conclude by arguing that this revision has the potential to strengthen and enhance case study research in Comparative and International Education, clarifying the unique contributions of qualitative research.

How can scholars trace the global production and circulation of educational policies? The vertical case study incorporates three elements: “vertical” attention across micro-, meso-, and macro-levels, or scales; a “horizontal” comparison of how policies unfold in distinct locations; and a “transversal,” processual analysis of the creative appropriation of educational policies across time. The second half of the article draws upon an ethnographic study of learner-centered pedagogy in Tanzania to exemplify the vertical case study approach.

This article examines how epistemological differences regarding knowledge production and material differences in the conditions of teaching influence teachers’ and teacher educators’ understandings of learner-centered pedagogy. Emerging from a 5-year collaboration between teams of US and Tanzanian teacher educators, the research focuses on six Tanzanian secondary schools whose teachers participated in a workshop on learner-centered pedagogy and pedagogical content knowledge. We find that teachers’ views of knowledge production are profoundly shaped by the cultural, economic, and social contexts in which they teach. We conclude not only that teachers’ working conditions are important contextual factors in comparative studies of schooling but that the conditions themselves need to be conceptualized more fully in theories of knowledge production and global/local reforms of teacher education.

The world is witnessing an era of unprecedented human mobility and much of this movement entails migration between countries in the global south. This article contributes to the development of an important new line of inquiry within the field of comparative and international education: South-South migration and education. In the first section, I review the available literature to sketch the outlines of this phenomenon. I then examine a particular case: schooling for youth of Haitian descent born and living in the Dominican Republic. The qualitative data reveals two important findings: first, despite claims to the contrary, some immigrant children are still being denied access to basic education; second, once enrolled in school, children and youth of Haitian descent, and especially darker-skinned boys, are subject to intense verbal abuse and, in some cases, physical abuse. As I discuss in the conclusion, the case of Haitians in the Dominican Republic raises significant questions regarding south-south migra...

For decades, Haitians have immigrated to the Dominican Republic in search of a better life, yet such hopes have been elusive for many. Since the 1980s, in the midst of shifting economic and political conditions, changing interpretations of the Constitution have increasingly denied Dominican citizenship to children born to Haitians in the Dominican Republic. Drawing on qualitative interviews with people of Haitian descent, the article demonstrates how citizenship claims are textually mediated, and it examines how agents of the Dominican state exert authority over Haitian- and Dominican-born people of Haitian descent through literacy events and literacy practices. Specifically, we consider not only how the withholding of documents shaped immigrants’ lives but also how state agents selectively and arbitrarily interpreted documents, such as passports, visas, birth certificates, and national identity cards, based upon various factors, including witnesses to the social interaction, whether bribes were forthcoming, and the state agent's determination of the social and economic value of the document bearer. While dominant development discourses routinely suggest that literacy skills provide a protective factor and potentially redress inequality, we demonstrate that literacy events are yet another social interaction in which authorities with power easily impose their interpretations on vulnerable populations.