Exploring ancestral phenotypes and evolutionary development of the mammalian middle ear based on Early Cretaceous Jehol mammals

We report a new Cretaceous multituberculate mammal with 3D auditory bones preserved. Along with other fossil and extant mammals, the unequivocal auditory bones display features potentially representing ancestral phenotypes of the mammalian middle ear. These phenotypes show that the ectotympanic and the malleus-incus complex changed notably during their retreating from the dentary at various evolutionary stages and suggest convergent evolution of some features to extant mammals. In contrast, the incudomalleolar joint was conservative in having a braced hinge configuration, which narrows the morphological gap between the quadroarticular jaw joint of non-mammalian cynodonts and the incudomalleolar articulations of extant mammals. The saddle-shaped and abutting malleus-incus complexes in therians and monotremes, respectively, could have evolved from the braced hinge joint independently. The evolutionary changes recorded in the Mesozoic mammals are largely consistent with the middle ear morphogenesis during the ontogeny of extant mammals, supporting the relation between evolution and development.     

Juggling competing activities: academic staff as doctoral candidates

ABSTRACT

This article explores the experiences of a group of established academic staff in New Zealand and the UK, as they undertake a doctorate in their home institutions. Our interest is in how individuals negotiate this dual status from a cultural-historical activity theory (CHAT) stance that explores how rules, tools, community and divisions of labour, and interacting activity systems, shape doctoral experiences. The focus in this article, having analysed their detailed narrative accounts, is on how academics experience three interdependent activity systems: those surrounding the thesis, the institutional context, and the home-life spheres. Issues related to time, workload and supervision issues, variability in collegial support and impact on personal priorities and time emerged. There is a range of particularities – from easy access to resources/supervisors to inflexible institutional regulations – applicable to this group of doctoral candidates. Negotiating life as an academic with concurrent doctoral candidature provides positive outcomes in terms of teaching, research confidence and general personal and professional development. However, a range of difficulties can also be encountered, particularly in relation to personal and professional relationships, and workload management.     

Remote effects of lower limb stretching: preliminary evidence for myofascial connectivity?

The skeletal muscles and the fibrous connective tissue form an extensive, body-wide network of myofascial chains. As fascia can modify its stiffness, strain transmission along these meridians is supposable. The goal of this trial therefore was to collect pilot data for potential remote effects of lower limb stretching on cervical range of motion (ROM). Twenty-six healthy participants (30 ± 6 years) were included in the matched-pairs intervention study. One group (n = 13) performed three 30 s bouts of static stretching for the gastrocnemius and the hamstrings, respectively. An age- and sex-matched control group (CG; n = 13) remained inactive. Pre- and post-intervention, maximal cervical ROM in flexion/extension was assessed. A repeated measures ANOVA revealed systematic differences between groups (P < .05). ROM increased following stretching (143.3 ± 13.9 to 148.2 ± 14°; P < .05) but remained unchanged in the CG (144.6 ± 16.8 to 143.3 ± 16.8°; P > .05). Our data point towards existence of a strain transfer along myofascial meridians. Further randomised controlled studies on conditions, factors and magnitude of tensile transmission are warranted.     

Mediating effects of resistance training skill competency on health-related fitness and physical activity: the ATLAS cluster randomised controlled trial

The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered “at-risk” of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys.     

Multivariate analyses of individual variation in soccer skill as a tool for talent identification and development: utilising evolutionary theory in sports science

The development of a comprehensive protocol for quantifying soccer-specific skill could markedly improve both talent identification and development. Surprisingly, most protocols for talent identification in soccer still focus on the more generic athletic attributes of team sports, such as speed, strength, agility and endurance, rather than on a player’s technical skills. We used a multivariate methodology borrowed from evolutionary analyses of adaptation to develop our quantitative assessment of individual soccer-specific skill. We tested the performance of 40 individual academy-level players in eight different soccer-specific tasks across an age range of 13–18 years old. We first quantified the repeatability of each skill performance then explored the effects of age on soccer-specific skill, correlations between each of the pairs of skill tasks independent of age, and finally developed an individual metric of overall skill performance that could be easily used by coaches. All of our measured traits were highly repeatable when assessed over a short period and we found that an individual’s overall skill – as well as their performance in their best task – was strongly positively correlated with age. Most importantly, our study established a simple but comprehensive methodology for assessing skill performance in soccer players, thus allowing coaches to rapidly assess the relative abilities of their players, identify promising youths and work on eliminating skill deficits in players.     

Evaluating the Instructional Sensitivity of Four States' Student Achievement Tests

As state tests of student achievement are used for an increasingly wide array of high- and low-stakes purposes, evaluating their instructional sensitivity is essential. This article uses data from the Bill and Melinda Gates Foundation's Measures of Effective Project to examine the instructional sensitivity of 4 states' mathematics and English language arts assessments to 5 measures of pedagogical quality. The results indicate modest overall levels of sensitivity, with some state assessments insensitive to most or all measures of pedagogical quality. Furthermore, there are sometimes substantial differences across states in the sensitivity of their assessments. The article calls for more research on what makes state tests instructionally sensitive and cautions against the use of insensitive assessments for consequential decisions.     

Conceptualizing Service-Learning in Christian Higher Education

Christian higher education is charged with the distinct mission of integrating faith and learning, and course-based service-learning has been identified as a supportive platform for this undertaking. Christian service-learning represents "a teaching and learning strategy that integrates academic instruction, community service, and guided reflection from a Christ-centered, faith-based perspective in order to enhance student learning, to foster civic responsibility, and to develop servant leaders” (Mullen, 2010 Mullen, S. (2010). Integrating a service and learning paradigm in a Christian education environment. Christian Education Journal, 7(1), 162–171.[Crossref] , [Google Scholar], p. 164). A large volume of literature pertaining to the theoretical and practical aspects of service-learning courses exists; however, the current literature and corresponding perceptions of best practice may not fully support the distinct nature of service-learning in Christian higher education. Therefore, the purpose of this article is to examine a predominant service-learning typology that dichotomizes traditional and critical service-learning (Mitchell, 2008 Mitchell, T. D. (2008). Traditional vs. critical service-learning: Engaging the literature to differentiate two models. Michigan Journal of Community Service Learning, 14(2), 50–65. [Google Scholar]) through the contextualization of faith-based higher education. Then, in an attempt to further elaborate upon Mullen’s (2010 Mullen, S. (2010). Integrating a service and learning paradigm in a Christian education environment. Christian Education Journal, 7(1), 162–171.[Crossref] , [Google Scholar]) definition, Morton’s (1995 Morton, K. (1995). The irony of service: Charity, project, and social change in service learning. Michigan Journal of Community Service Learning, 2(1), 19–32. [Google Scholar]) typology is recommended to frame Christian service-learning as it acknowledges the validity of multiple paradigms of service-learning (charity, project, and social change) and emphasizes the manner of their implementation (thick versus thin). Micro- and macro-level strategies, based on Morton’s (1995 Morton, K. (1995). The irony of service: Charity, project, and social change in service learning. Michigan Journal of Community Service Learning, 2(1), 19–32. [Google Scholar]) typology and subsequent recommendations, are provided to support faculty members and administrators attempting to implement and sustain service-learning at faith-based institutions. Specifically, Christian institutions should prioritize faith-based organizations as core partners, and faculty members should intentionally utilize reflection to integrate faith and learning.