“Praxticing” critical coaching: disrupting traditional youth sport coaching with social justice and critical consciousness

The current study explored coach training and experience, and individual identities and roles that youth sport coaches hold as well as how they enact social justice within youth sporting communities. Using convergent mixed-methods design, critical consciousness (Freire, 1970) was the theoretical framework and method of analysis for this study. Forty-seven participants responded to this open-ended survey; 85.1% of coaches reported coaching part-time, 59.5% of the sample were volunteer coaches, and 33% of coaches had less than 1–3 years of coaching experience. Findings revealed a majority White (69%) and Majority Male (61%) sample of youth sport coaches and described coaching identities were categorized into multiple and intersectional (Women of Color; n = 5) identities. Emic coding through cross-analysis of open-ended questions suggested a deeper understanding of coaches’ connection to community in relationship to how coaches described identities. These were coded as Coach-Centered Coaching , Limited Connection, or Synthesizing Connection. Furthermore, community-based sport coaches were engaging in and enacting social justice within youth sporting communities in ways that mirror critical consciousness patterns of dialogue, reflection, and action. The theoretical implications of this study expand the application of societal roles, more specifically the role of a youth sport coach to the theory of intersectionality. This study supports past literature that found that youth sport coaches are dissatisfied with the education they receive; thus these findings inform suggestions for how to make coaching education more relevant and accessible. Empirically, study findings suggest that the underresearched area of youth sport coaches’ identities may be related to the depth of connection coaches have to community, impacting the holistic developmental outcomes of participating youth athletes. Practically, this study delivers a critical pedagogy framework for community-based coaching education that blends the personal (identity and role development) and professional (coaching specific knowledges). Results of this study can inform future empirical research of youth sport coaching and intervention development that theoretically considers the integration of intersectionality with critical consciousness

Connectivity and tree structure in finite graphs

Considering systems of separations in a graph that separate every pair of a given set of vertex sets that are themselves not separated by these separations, we determine conditions under which such a separation system contains a nested subsystem that still separates those sets and is invariant under the automorphisms of the graph. As an application, we show that the $k$-blocks -- the maximal vertex sets that cannot be separated by at most $k$ vertices -- of a graph $G$ live in distinct parts of a suitable tree-decomposition of $G$ of adhesion at most $k$, whose decomposition tree is invariant under the automorphisms of $G$. This extends recent work of Dunwoody and Kr\"on and, like theirs, generalizes a similar theorem of Tutte for $k=2$. Under mild additional assumptions, which are necessary, our decompositions can be combined into one overall tree-decomposition that distinguishes, for all $k$ simultaneously, all the $k$-blocks of a finite graph.Comment: 31 page

An update on vitamin B12-related gene polymorphisms and B12 status.

Vitamin B12 is an essential micronutrient in humans needed for health maintenance. Deficiency of vitamin B12 has been linked to dietary, environmental and genetic factors. Evidence for the genetic basis of vitamin B12 status is poorly understood. However, advancements in genomic techniques have increased the knowledge-base of the genetics of vitamin B12 status. Based on the candidate gene and genome-wide association (GWA) studies, associations between genetic loci in several genes involved in vitamin B12 metabolism have been identified. The objective of this literature review was to identify and discuss reports of associations between single-nucleotide polymorphisms (SNPs) in vitamin B12 pathway genes and their influence on the circulating levels of vitamin B12. Relevant articles were obtained through a literature search on PubMed through to May 2017. An article was included if it examined an association of a SNP with serum or plasma vitamin B12 concentration. Beta coefficients and odds ratios were used to describe the strength of an association, and a  < 0.05 was considered as statistically significant. Two reviewers independently evaluated the eligibility for the inclusion criteria and extracted the data. From 23 studies which fulfilled the selection criteria, 16 studies identified SNPs that showed statistically significant associations with vitamin B12 concentrations. Fifty-nine vitamin B12-related gene polymorphisms associated with vitamin B12 status were identified in total, from the following populations: African American, Brazilian, Canadian, Chinese, Danish, English, European ancestry, Icelandic, Indian, Italian, Latino, Northern Irish, Portuguese and residents of the USA. Overall, the data analyzed suggests that ethnic-specific associations are involved in the genetic determination of vitamin B12 concentrations. However, despite recent success in genetic studies, the majority of identified genes that could explain variation in vitamin B12 concentrations were from Caucasian populations. Further research utilizing larger sample sizes of non-Caucasian populations is necessary in order to better understand these ethnic-specific associations