Exploring the association between income inequality and sleep in Canadian adolescents: A path analysis approach.

OBJECTIVES: An estimated 30% of Canadian adolescents do not get the recommended 8-10hours of sleep. No prior study has examined the role of income inequality, the gap between rich and poor within a society, in adolescent sleep. The aim of this study is to examine the association between income inequality and sleep duration among Canadian adolescents, how this association differs by gender, and whether depressive symptoms, anxiety, and social cohesion mediate this relationship. METHODS: Multilevel path models were conducted using cross-sectional survey data from 74,501 adolescents who participated in the Cannabis, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behavior (COMPASS) study in 2018-2019. Income inequality was measured at the census division level and sleep duration, gender, depressive symptoms, anxiety, and social cohesion were measured at the individual level. RESULTS: A 1% increase in income inequality was associated with a 3.67-minute decrease in sleep duration (95% CI=-5.64 to -1.70). The cross-level interactions between income inequality and gender were significant, suggesting that income inequality has more adverse associations with sleep among females than males. Both depressive symptoms and anxiety were significant mediators, wherein greater income inequality was associated with higher levels of depressive symptoms and anxiety, which were in turn, associated with a shorter sleep duration. CONCLUSION: Interventions that reduce income inequality may prevent depressive symptoms and anxiety and improve sleep in adolescents. Reducing societal income gaps may improve adolescent sleep especially in those attending school in high income inequality areas, females, and those experiencing depressive symptoms and anxiety.

Partnership-building considerations for implementation science in learning health systems: a case study of the Implementation Science Collaborative in Alberta, Canada.

Introduction: Implementation of health innovations is inherently collaborative, requiring trans-sectoral partnerships between implementation researchers, innovation teams, and implementation practitioners. Implementation science has been shown to improve implementation successes; however, challenges that hinder partnerships to advance implementation science continue to persist. Using a whole-system approach to assess and respond to implementation science partnership barriers may shed light on effective responses. Methods: We conducted a case study of Alberta's learning health system, using semi-structured group and individual interviews to create a nuanced understanding of the considerations required for implementation research collaborations. We interviewed 53 participants representing 21 offices in the health system, academia, professional associations, and government who regularly plan, evaluate, and/or study health system implementation initiatives in Alberta. Using the Partnership Model for Research Capacity Building, we identified current facilitators and challenges for partnerships for conducting and using implementation science, at different levels of Alberta's health-research ecosystem. Results: Alberta's healthcare system is well set up to readily embed intervention effectiveness and efficacy research. Infrastructure was also in place to strengthen implementation practice. However, weaknesses around exchanging knowledge and skills, providing feedback and mentoring, and accommodating diversity affected the ability of both individuals and teams to build implementation science capacity. Without this capacity, teams could not participate in embedded implementation research collaborations. We report the response of the Alberta Strategy for Patient-Oriented Research SUPPORT Unit to these barriers to provide practical guidance on various program options to strengthen individual- and organization-level implementation science capacity. Discussion: This study applied a whole-system approach to assess factors across Alberta's health-research ecosystem, which affect partnerships to advance implementation science. Our findings illustrated that partnership considerations go beyond interpersonal factors and include system-wide considerations. With the results, health organization leaders have (1) a method for assessing organizational capability to readily embed implementation research and (2) a catalog of potential responses to create conditions to readily engage with implementation science in their day-to-day implementation processes.

"Your Kid Has Potential, But They Need Sleep": Teacher Perspectives on School-Based Sleep Promotion in Alberta, Canada.

BACKGROUND: Insufficient sleep is a growing public health concern. Thirty percent of Canadian children and youth are not meeting national sleep recommendations. Inadequate sleep can negatively influence students' academics and physical and psychosocial health. Schools have been identified as ideal health promotion settings to influence children's health including their sleep behaviors. The objective of this study was to explore teachers' perspectives on sleep behaviors and their role in school-based sleep promotion. METHODS: Nineteen elementary teachers were purposively sampled from the greater Edmonton area, Alberta, Canada. Interpretive description was used as the guiding method, and data were generated through one-on-one semi-structured interviews. Inductive descriptive thematic analysis was used to identify interview themes. RESULTS: Three themes related to teachers' perspectives on sleep behaviors and school-based sleep promotion were identified: the importance of students' sleep, prioritizing sleep as part of teaching and learning, and a culture of healthy sleep habits. CONCLUSIONS: This study found that teachers considered sleep to be essential for elementary students' academic success and wellbeing, and a whole school approach was necessary to support a healthy sleep culture in schools.

Prioritizing a research agenda on built environments and physical activity: a twin panel Delphi consensus process with researchers and knowledge users.

BACKGROUND: The growth of urban dwelling populations globally has led to rapid increases of research and policy initiatives addressing associations between the built environment and physical activity (PA). Given this rapid proliferation, it is important to identify priority areas and research questions for moving the field forward. The objective of this study was to identify and compare research priorities on the built environment and PA among researchers and knowledge users (e.g., policy makers, practitioners). METHODS: Between September 2022 and April 2023, a three-round, modified Delphi survey was conducted among two independent panels of international researchers (n = 38) and knowledge users (n = 23) to identify similarities and differences in perceived research priorities on the built environment and PA and generate twin 'top 10' lists of the most important research needs. RESULTS: From a broad range of self-identified issues, both panels ranked in common the most pressing research priorities including stronger study designs such as natural experiments, research that examines inequalities and inequities, establishing the cost effectiveness of interventions, safety and injuries related to engagement in active transportation (AT), and considerations for climate change and climate adaptation. Additional priorities identified by researchers included: implementation science, research that incorporates Indigenous perspectives, land-use policies, built environments that support active aging, and participatory research. Additional priorities identified by knowledge users included: built environments and PA among people living with disabilities and a need for national data on trip chaining, multi-modal travel, and non-work or school-related AT. CONCLUSIONS: Five common research priorities between the two groups emerged, including (1) to better understand causality, (2) interactions with the natural environment, (3) economic evaluations, (4) social disparities, and (5) preventable AT-related injuries. The findings may help set directions for future research, interdisciplinary and intersectoral collaborations, and funding opportunities.

Parental Perspectives of Sleep in the Home: Shaping Home-School Partnerships in School-Based Sleep Promotion Initiatives.

INTRODUCTION: Sleep is a critical component of child health and the prevention of chronic disease. Children may benefit from school-based sleep promotion; however, parents need to be involved for healthy sleep strategies learned at school to be translated to the home. The objective of this study was to explore parental perspectives on sleep behaviors and responsiveness to school-based sleep promotion. METHODS: Twenty-five parents of school-aged children were purposively sampled for interviews from July 2019 through April 2020 in Alberta, Canada. Descriptive qualitative methodology was used, and data were generated through semistructured interviews and researcher field notes. Interviews were transcribed and themes were identified by using latent content analysis. RESULTS: Three themes emerged from analysis: 1) sleep is valued and supported, 2) barriers to healthy sleep exist, and 3) schools are allies in promoting sleep. Parents perceived that sleep was essential for their child's health, facilitated healthy sleep practices in the home, and highlighted barriers (busy schedules and poor parental role models) that affected sleep. Parents supported and expressed value in school-based sleep promotion and noted factors that affected the success of school-based sleep promotion. CONCLUSION: Parents are responsive to school-based sleep promotion. Promotion efforts should include resources that engage and involve parents in the school community. Throughout the development of resources to support school-based sleep promotion, additional consideration of parent-reported barriers to promoting healthy sleep in the home should be included.

Prioritizing well-being in K-12 education: lessons from a multiple case study of Canadian school districts.

Increasingly, school districts are looking for insights on how to embed a well-being focus across school communities. Well-being in K-12 education is proven to support positive mental health, improve academic performance and contribute to positive outcomes for students and staff. How districts transition to deeply integrate well-being into existing priorities and practices is not well understood. Insights on such shifts can help inform widespread change in education. In 2020, six Canadian school districts participated in case study research to examine how and why districts were able to shift their culture to one that prioritizes well-being. Fifty-five school community members participated in individual semi-structured interviews to explore their perception of well-being in their school communities. Analysis identified six themes: well-being is wholistic and requires balance, student and staff well-being are interconnected, organizational leadership sustains implementation, connection and voice as a catalyst to well-being, building capacity to support well-being action, and charting and re-charting a course. Findings increase our understanding of system-level change, and provide insights to support well-being in education.

Well-being in K-12 education is proven to support positive mental health, improve academic performance and contribute to positive outcomes for students and staff. How school districts can deeply integrate well-being into existing priorities and practices is not well understood. Many districts are looking for insights on how to embed a well-being focus across school communities. These insights can help inform change in K-12 education. In 2020, six Canadian school districts participated in case study research to examine how and why districts were able to shift their culture to one that prioritizes well-being. Fifty-five participants from six districts took part in interviews on the topic of district well-being prioritization. Supporting documents were also reviewed. Qualitative analysis identified six common themes: well-being is wholistic and requires balance, student and staff well-being are interconnected, organizational leadership sustains implementation, connection and voice as a catalyst to well-being, building capacity to support well-being action, and charting and re-charting a course. Study findings increase our understanding of system-level change in K-12 education. Findings provide valuable 'entry points' for school and district leaders to consider when making well-being a priority in their own contexts.

An ependymal cell census identifies heterogeneous and ongoing cell maturation in the adult mouse spinal cord that changes dynamically on injury.

The adult spinal cord stem cell potential resides within the ependymal cell population and declines with age. Ependymal cells are, however, heterogeneous, and the biological diversity this represents and how it changes with age remain unknown. Here, we present a single-cell transcriptomic census of spinal cord ependymal cells from adult and aged mice, identifying not only all known ependymal cell subtypes but also immature as well as mature cell states. By comparing transcriptomes of spinal cord and brain ependymal cells, which lack stem cell abilities, we identify immature cells as potential spinal cord stem cells. Following spinal cord injury, these cells re-enter the cell cycle, which is accompanied by a short-lived reversal of ependymal cell maturation. We further analyze ependymal cells in the human spinal cord and identify widespread cell maturation and altered cell identities. This in-depth characterization of spinal cord ependymal cells provides insight into their biology and informs strategies for spinal cord repair.

It takes a community: exploring APPLE Schools' impact within and beyond school walls in Canada.

Childhood is a critical stage to develop healthy behaviours, and the school years are an important developmental period in which children are learning and growing. School-based health promotion interventions are increasingly using the comprehensive school health (CSH) approach that has been found effective at improving health behaviours, while adapting to the school and community context to create and sustain a healthy school culture. The interconnected environments of school, home and community are key to the CSH approach, however, there is minimal research that has been conducted to determine the impact at the community-level. This research used a qualitative multiple case study design to explore the influence of a school-based health promotion intervention, APPLE Schools, on the school and community environments from the perspectives of school staff in Alberta, Canada. Twenty-two participants participated in walking interviews in five schools. The walking interview approach combined interviewing and field observation and empowered participants to share their local expertise and knowledge within the context of school and community environments. Interviews were transcribed and analysed using an inductive thematic approach. Four themes were identified: APPLE schools look different, APPLE Schools build champions, APPLE Schools builds community partnerships and APPLE Schools honours community culture. Health promotion practice in schools was uniquely adapted based on strengths and needs of each school and was broadly influenced by the community outside of school walls. In sum, it was found that school-based health promotion reaches beyond school walls and can influence the broader community environment.

Childhood is a critical stage to develop healthy behaviours, and the school years are an important developmental period in which children are learning and growing. School-based health promotion interventions are increasingly using the comprehensive school health (CSH) approach. CSH has been found effective in improving health and educational outcomes, including quality of life, healthy eating, physical activity, mental wellness and academic achievement. The interconnected environments of school, home and community are key to the CSH approach, however, there is minimal research that has been conducted to determine the impact at the community-level. This research used a qualitative multiple case study design to explore the influence of a school-based health promotion intervention, APPLE Schools, on the school and community environments from the perspectives of school staff in Canada. Twenty-two participants from five schools, took part in walking interviews. Interviews were transcribed and analysed for patterns and common themes. Four themes were identified: APPLE schools look different, APPLE Schools build champions, APPLE Schools builds community partnerships and APPLE Schools honours community culture. It was found that school-based health promotion reaches beyond school walls and can influence the broader community environment. This understanding will support stronger school­community relationships in future interventions.

ERK1/2 signalling dynamics promote neural differentiation by regulating chromatin accessibility and the polycomb repressive complex.

Fibroblast growth factor (FGF) is a neural inducer in many vertebrate embryos, but how it regulates chromatin organization to coordinate the activation of neural genes is unclear. Moreover, for differentiation to progress, FGF signalling must decline. Why these signalling dynamics are required has not been determined. Here, we show that dephosphorylation of the FGF effector kinase ERK1/2 rapidly increases chromatin accessibility at neural genes in mouse embryos, and, using ATAC-seq in human embryonic stem cell derived spinal cord precursors, we demonstrate that this occurs genome-wide across neural genes. Importantly, ERK1/2 inhibition induces precocious neural gene transcription, and this involves dissociation of the polycomb repressive complex from key gene loci. This takes place independently of subsequent loss of the repressive histone mark H3K27me3 and transcriptional onset. Transient ERK1/2 inhibition is sufficient for the dissociation of the repressive complex, and this is not reversed on resumption of ERK1/2 signalling. Moreover, genomic footprinting of sites identified by ATAC-seq together with ChIP-seq for polycomb protein Ring1B revealed that ERK1/2 inhibition promotes the occupancy of neural transcription factors (TFs) at non-polycomb as well as polycomb associated sites. Together, these findings indicate that ERK1/2 signalling decline promotes global changes in chromatin accessibility and TF binding at neural genes by directing polycomb and other regulators and appears to serve as a gating mechanism that provides directionality to the process of differentiation.

An Environmental Scan of Existing Canadian Childcare Resources Targeting Improvements in Health Behaviours.

The objective was to conduct an environmental scan of existing Canadian childcare resources targeting nutrition, physical activity, sedentary behaviour, and/or sleep. A comprehensive search plan was conducted that involved four search strategies: (1) grey literature databases, (2) customized Google search engines, (3) targeted websites, and (4) consultation with content experts. A resource (i.e., information, materials) must have been created by government or an organization/agency within Canada, available in English, intended for childcare educators or directors working with children ≤ 5 years of age, and focused on targeting improvements in nutrition, physical activity, sedentary behaviour, and/or sleep. The quality of each included resource was assessed using a modified version of the Authority, Accuracy, Coverage, Objectivity, Date, Significance checklist. A total of 192 eligible resources were included. Most resources targeted only nutrition (n = 101) or physical activity (n = 60), and few resources targeted only sedentary behaviour (n = 2) or sleep (n = 1). The remaining 28 resources targeted more than one health behaviour. The 4 most common topics of resources were menu/meal planning (n = 55), healthy nutrition practices/environment (n = 37), physical activities/games (n = 33), and nutrition/food literacy (n = 20). Only 52 included resources cited evidence. One-third of the included resources (n = 64) were rated as high quality, including 55 that received a point for the significance criterion. Therefore, numerous high quality Canadian childcare resources exist for nutrition and physical activity. Future resource development is needed for sedentary behaviour and sleep. Findings can assist future intervention work and the database of resources can be utilized by relevant stakeholders to support other childcare initiatives. Supplementary Information: The online version contains supplementary material available at 10.1007/s10643-021-01266-2.

"We're categorized in these sizes-that's all we are": uncovering the social organization of young women's weight work through media and fashion.

BACKGROUND: For decades, dominant weight discourses have led to physical, mental, and social health consequences for young women in larger bodies. While ample literature has documented why these discourses are problematic, knowledge is lacking regarding how they are socially organized within institutions, like fashion and media, that young women encounter across their lifespan. Such knowledge is critical for those in public health trying to shift societal thinking about body weight. Therefore, we aimed to investigate how young women's weight work is socially organized by discourses enacted in fashion and media, interpreting work generously as any activity requiring thought or intention. METHODS: Using institutional ethnography, we learned from 14 informants, young women aged 15-21, in Edmonton, Canada about the everyday work of growing up in larger bodies. We conducted 14 individual interviews and five repeated group interviews with a subset (n = 5) of our informants. A collaborative investigation of weight-related YouTube videos (n = 45) elicited further conversations with two informant-researchers about the work of navigating media. Data were integrated and analyzed holistically. RESULTS: Noticing the perpetual lack of larger women's bodies in fashion and media, informants learned from an early age that thinness was required for being seen and heard. Informants responded by performing three types of work: hiding their weight, trying to lose weight, and resisting dominant weight discourses. Resistance work was aided by social media, which offered informants a sense of community and opportunities to learn about alternative ways of knowing weight. However, social media alleging body acceptance or positivity content often still focused on weight loss. While informants recognized the potential harm of engagement with commercial weight loss industries like diet and exercise, they felt compelled to do whatever it might take to achieve a "normal woman body". CONCLUSIONS: Despite some positive discursive change regarding body weight acceptance in fashion and media, this progress has had little impact on the weight work socially expected of young women. Findings highlight the need to broaden public health thinking around how weight discourses are (re)produced, calling for intersectoral collaboration to mobilize weight stigma evidence beyond predominantly academic circles into our everyday practices.

Citizen science in monitoring food environments: a qualitative collective case study of stakeholders' experiences during the Local Environment Action on Food project in Alberta, Canada.

BACKGROUND: Citizen science bears potential to build a comprehensive view of global food environments and create a broader discussion about how to improve them. Despite its potential, citizen science has not been fully utilised in food environment research. Thus, we sought to explore stakeholders' experiences of the Local Environment Action on Food (LEAF) project, a community-based intervention that employs a citizen science approach to monitoring food environments. METHODS: We used a qualitative collective case study design to explore citizen science through the LEAF process in seven communities in Alberta, Canada. Data generating strategies included semi-structured interviews with citizen scientists (n = 26), document review of communities' Mini Nutrition Report Cards (n = 7), and researcher observation. Data were analyzed in a multi-phase process, using Charmaz's constant comparison analysis strategy. RESULTS: Analysis revealed two main themes: relationship building and process factors. Communities used three interconnected strategies, engaging the right people, treading lightly, and reaching a consensus, to navigate the vital but challenging relationship building process. Process factors, which were influences on the LEAF process and relationship building, included the local context, flexibility in the LEAF process, and turnover among LEAF community groups. CONCLUSION: Citizen science through the LEAF project supported the creation and application of food environment evidence: it enabled residents to collect and interpret local food environment data, develop realistic recommendations for change, and provided them with an evidence-based advocacy tool to support the implementation of these recommendations. We recommend a web application that enables independent community food environment assessments. Such a tool could stimulate and sustain citizen involvement in food environment efforts, helping to build the necessary evidence base and promote the creation of healthy food environments.

Choice, Motives, and Mixed Messages: A Qualitative Photo-Based Inquiry of Parents' Perceptions of Food and Beverage Marketing to Children in Sport and Recreation Facilities.

Unhealthy food and beverage availability and sponsorship undermine healthy food practices in sport and recreation. We conducted a focused ethnography with reflexive photo-interviewing to examine parents' awareness, reactions, and experiences of food and beverage marketing in and around their children's physical activity in public sport and recreation facilities. Eleven parents took photos of what they thought their facility was 'saying about food and eating'. Photos guided semi-structured interviews on the '4Ps' of marketing (product, pricing, placement, promotion). Thematic analysis was conducted by holistic coding followed by in vivo, versus, and value coding. Photo-taking increased parents' awareness of food marketing in facilities. Reactions to food and beverage marketing were positive or negative depending on parents' perspectives of healthy food availability (choice), marketers' motives, and mixed messages within the facility. Parents experienced their children requesting 'junk' food at the facility leading to parents actively attempting to reduce the frequency of these requests. Healthy eating promotion in sport and recreation facilities was misaligned with the foods and beverages available which contributed to parents' distrust of social marketing initiatives. Critically evaluating the alignment of commercial and social marketing in recreation and sport may help inform effective healthy eating interventions that are accepted and supported by parents.

Use of Photovoice to Explore Pediatric Patients with Hypertrophic Cardiomyopathy and their Parents' Perceptions of a Heart-Healthy Lifestyle.

Background Heart-healthy lifestyles promote lifelong cardiovascular health. However, patients with hypertrophic cardiomyopathy are often advised to avoid strenuous exercise because of the risk of sudden cardiac death. Given these restrictions, this study explored youth and parent perceptions of a heart-healthy lifestyle and the barriers and facilitators to this lifestyle. Methods and Results Youth and parents were purposefully recruited at 2 Canadian hospitals for this photovoice project. Participants were given cameras and took pictures of everyday heart-healthy or heart-unhealthy choices. Photos were discussed during one-on-one qualitative interviews with youth and parents separately to understand the photos' meaning and significance. Inductive descriptive thematic analysis was employed. A total of 16 youth (median age, 14.4 years [range, 10.5-17.7 years]; 63% boys) and 16 parents (100% women) participated. A total of 15 youth were activity restricted. Data analysis revealed 7 categories organized into perceptions of healthy living (health is holistic and individualized) and factors influencing engagement in healthy living (self-awareness, ownership and autonomy, feeling restricted and peer pressure, support from parents, and support from the cardiologist). Participants had a complex understanding of health and discussed the importance of physical, mental, and social well-being. Youth used self-awareness and taking responsibility as facilitators of healthy living. Healthy living was shaped by peers, parent role-modeling, and cardiologist recommendations. Conclusions This study depicts the realities for youth with hypertrophic cardiomyopathy and can be used to inform the development of responsive interventions. Holistic, patient-specific interventions may be more successful, and strategies such as shared decision making may be important to promote self-awareness and autonomy.

Human spinal cord in vitro differentiation pace is initially maintained in heterologous embryonic environments.

Species-specific differentiation pace in vitro indicates that some aspects of neural differentiation are governed by cell intrinsic properties. Here we describe a novel in vitro human neural-rosette assay that recapitulates dorsal spinal cord differentiation but proceeds more rapidly than in the human embryo, suggesting that it lacks endogenous signalling dynamics. To test whether in vitro conditions represent an intrinsic differentiation pace, human iPSC-derived neural rosettes were challenged by grafting into the faster differentiating chicken embryonic neural tube iso-chronically, or hetero-chronically into older embryos. In both contexts in vitro differentiation pace was initially unchanged, while long-term analysis revealed iso-chronic slowed and hetero-chronic conditions promoted human neural differentiation. Moreover, hetero-chronic conditions did not alter the human neural differentiation programme, which progressed to neurogenesis, while the host embryo advanced into gliogenesis. This study demonstrates that intrinsic properties limit human differentiation pace, and that timely extrinsic signals are required for progression through an intrinsic human neural differentiation programme.

The essential conditions needed to implement the Indigenous Youth Mentorship Program: a focused ethnography.

BACKGROUND: The Indigenous Youth Mentorship Program (IYMP) is a 20-week communal, relationship-based afterschool healthy living program for Indigenous youth in Canada. IYMP embraces the Anishnaabe/Nehiyawak concepts of Mino-Bimaadiziwin/miyo-pimâtisiwin ("living in a good way") via its core components of physical activities/games, healthy snacks, and relationship-building. A strength of IYMP is that it values autonomy, adaptability, and the school community context. However, this presents challenges when evaluating its implementation, given that traditional implementation science methods tend to oversimplify the process. In response, essential conditions for the implementation of school-based healthy living programs across diverse contexts have been developed. The purpose of this research was to understand the applicability of these essential conditions within the context of IYMP. METHODS: 15 participants (n = 10 Young Adult Health Leaders; n = 5 coordinators) with experience implementing IYMP in the provinces of Alberta, Saskatchewan, Manitoba, and Quebec were purposefully sampled. Focused ethnography was the guiding method and one-on-one semi-structured interviews were used as the data generation strategy. The purpose of the interviews was to understand what conditions are needed to implement IYMP. The interview guide was based on previously established essential conditions developed by the research team. Interviews were audio-recorded and transcribed, and content analysis was used to identify patterns in the data. RESULTS: The overarching theme that emerged from the interviews was the applicability of the essential conditions when implementing IYMP. Participants felt the eight core conditions (students as change agents, school/community-specific autonomy, demonstrated administrative leadership, higher-level support, dedicated champion(s) to engage school community, community support, quality and use of evidence, and professional development) and four contextual conditions (time, funding and project support, readiness and understanding, and prior community connectivity) were necessary, but made suggestions to modify two conditions (youth led and learning opportunities) to better reflect their experiences implementing IYMP. In addition, a new core condition, rooted in relationship, emerged as necessary for implementation. CONCLUSIONS: This research adds to the literature by identifying and describing what is needed in practice to implement a communal, relationship-based afterschool healthy living program. The essential conditions may support other researchers and communities interested in implementing and rippling similar programs.

A lateral protrusion latticework connects neuroepithelial cells and is regulated during neurogenesis.

Dynamic contacts between cells within the developing neuroepithelium are poorly understood but play important roles in cell and tissue morphology and cell signalling. Here, using live-cell imaging and electron microscopy we reveal multiple protrusive structures in neuroepithelial apical endfeet of the chick embryonic spinal cord, including sub-apical protrusions that extend laterally within the tissue, and observe similar structures in human neuroepithelium. We characterise the dynamics, shape and cytoskeleton of these lateral protrusions and distinguish them from cytonemes, filopodia and tunnelling nanotubes. We demonstrate that lateral protrusions form a latticework of membrane contacts between non-adjacent cells, depend on actin but not microtubule dynamics, and provide a lamellipodial-like platform for further extending fine actin-dependent filipodia. We find that lateral protrusions depend on the actin-binding protein WAVE1 (also known as WASF1): misexpression of mutant WAVE1 attenuated protrusion and generated a round-ended apical endfoot morphology. However, this did not alter apico-basal cell polarity or tissue integrity. During normal neuronal delamination, lateral protrusions were withdrawn, but precocious protrusion loss induced by mutant WAVE1 was insufficient to trigger neurogenesis. This study uncovers a new form of cell-cell contact within the developing neuroepithelium, regulation of which prefigures neuronal delamination. This article has an associated First Person interview with the first author of the paper.

Local Environment Action on Food project: impact of a community-based food environment intervention in Canada.

Children are exposed to food environments that make nutrient-poor, energy-dense food cheap, readily available and heavily marketed; all conditions with potential negative impacts on diet and health. While the need for programmes and policies that improve the status of food environments is clear, greater public support is needed for governments to act. The purpose of this qualitative collective case study was to examine if community engagement in the Local Environment Action on Food (LEAF) project, a community-based food environment intervention in Alberta, Canada, could build public support and create action to promote healthy food environments. Semi-structured interviews with a purposeful sample of 26 stakeholders from 7 communities explored LEAF's impact and stakeholder experiences creating change. Data collection and analysis were iterative, following Charmaz's constant comparative analysis strategy. Participants reported environmental and community impacts from LEAF. Notably, LEAF created a context-specific tool, a Mini Nutrition Report Card, that communities used to promote and support food environment action. Further, analysis outlined perceived barriers and facilitators to creating community-level food environment action, including level of engagement in LEAF, perceived controllability, community priorities, policy enforcement and resources. Findings from this study suggest that community-based interventions, such as LEAF, can help build community capacity and reduce existing barriers to community-level food environment action. Thus, they can provide an effective method to build public awareness, demand and action for healthier food environments.

Indigenous Youth Mentorship Program: essential characteristics of a Canadian multi-site community-university partnership with Indigenous communities.

The Indigenous Youth Mentorship Program (IYMP) is a peer-led health promotion program grounded in the teachings of Indigenous scholars. IYMP is delivered as a multi-sited community-university partnership (CUP) with Indigenous communities across Canada for elementary students. A local young adult health leader and high school youth mentors offer students healthy snacks, physical activity games, relationship building activities and traditional cultural teachings. IYMP aims to improve children's health and wellbeing and empower Indigenous youth and communities. The purpose of this descriptive qualitative study was to describe the essential characteristics of this multi-sited CUP as perceived by the IYMP principal investigators (PIs). Key informant interviews were conducted with 5 IYMP PIs (2 Indigenous) and analysed using content analysis. The overarching theme was forming a community of practice (CoP), where people with a common interest share best practices as they interact regularly. Four sub-themes were shared interest for Indigenous health/wellbeing and social justice, relationships, mentorship and taking a decolonizing research approach. The IYMP CoP allowed mentorship to occur across regions. The essential characteristics that made the IYMP CUPs successful could be used to inform other multi-sited CUPs with Indigenous communities. Those with mutual interests in Indigenous health and partnership with Indigenous communities could consider forming a CoP. Within a newly formed CoP, relationships and mentorship can be developed through discussion and activities. It is imperative within the CoP to take a decolonizing approach to research and acknowledge the impact that colonial policies and practices have had on generations of Indigenous peoples.