Historical Evolution of the Field View and Textbook Accounts

We analyzed how two basic electromagnetism textooks approach the concept of electric field. We limited our study to the reasons given in these textbooks for the introduction of the field representation and to how accurate, coherent, and complete these reasons are. Because many times historical reasons are intertwined with textbooks' explanations of physical phenomena, we used the historical evolution of the field representation to guide our analysis. The analysis shows that one textbook mixes up the historical and pedagogical reasons for the introduction of the concept of field. The other one presents a sketch that might lead students to understand the field and the action-at-a-distance views as supplementing each other.     

Explanations of attitudes to change: Colombian mathematics teachers’ conceptions of the crucial determinants of their teaching practices of beginning algebra

This article arises from a study whose overall purpose was to investigate the relationship between Colombian mathematics teachers’ conceptions of beginning algebra and their conceptions of their own teaching practices. The teachers’ understandings of their teaching practices were explored with a view to unravelling their conceptions of change in their teaching. Focusing on the perspectives of teachers afforded opportunities that exposed the powerful role that the teachers’ conceptions of social/institutional factors of teaching played in their conceptions of their practices. The degree to which the teachers attributed these (external) factors as crucial reasons for what they do in their teaching was the basis of a categorisation of their conceptions of the crucial determinants of their teaching practices into three types. The findings are particularly relevant to our understanding of the stability of mathematics teaching approaches in the Colombian context but have likely implications for a range of international education contexts. Specific implications for the development of the research into teachers’ conceptions of mathematics and its teaching, and for teacher education programmes are presented.

Reception of Stuart Hall in the Korean intellectual field

After Stuart Hall’s death in 2014, Korean newspapers ran detailed obituaries praising him as an influential British intellectual figure. The broad media attention appears to be unusual, given that he maintained a relatively unknown presence in the Korean cultural fields compared with other theorists. This work examines how and in which context Hall’s writings have been cited, or not cited, and emphasized in the Korean cultural studies. The incorporation of Hall’s writings into the resources of the academic field entangled him in scholarly rituals of parochial citations and applications, resulting in the fragmentation and de-contextualization of Hall’s overall problem. The selective focus on and occasional absence of certain aspects among his intellectual and political legacies may demonstrate how imported British cultural studies have, or not yet, been indigenized and localized in Korean cultural and political contexts.     

USING FOCUS GROUPS AS AN EDUCATIONAL METHODOLOGY: DECONSTRUCTING STEREOTYPES AND SOCIAL WORK PRACTICE MISCONCEPTIONS CONCERNING AGING AND OLDER ADULTS

During the coming years the number of older adults will increase dramatically, which will require a corresponding increase in the number of social workers who have accurate knowledge of this population. This article reports the impact focus groups with older adults and with service providers who work with older adults and their families have on baccalaureate social work (BSW) students. We find that BSW students exposed to focus groups have their negative attitudes about older adults and service providers deconstructed and replaced with more positive and accurate information about older adults. When students' misconceptions about older adults are confronted, they become more interested in choosing geriatric social work as a career option.     

Temporal aspects of the VO2 response at the power output associated with VO2peak in well trained cyclists--implications for interval training prescription

The power output achieved at peak oxygen consumption (VO2peak) and the time this power can be maintained (i.e., Tmax) have been used in prescribing high-intensity interval training. In this context, the present study examined temporal aspects of the VO2 response to exercise at the cycling power that output well trained cyclists achieve their VO2peak (i.e., Pmax). Following a progressive exercise test to determine VO2peak, 43 well trained male cyclists (M age = 25 years, SD = 6; M mass = 75 kg, SD = 7; M VO2peak = 64.8 ml x kg(-1) x min(-1), SD = 5.2) performed two Tmax tests 1 week apart. Values expressed for each participant are means and standard deviations of these two tests. Participants achieved a mean VO2peak during the Tmax test after 176 s (SD = 40; M = 74% of Tmax, SD = 12) and maintained it for 66 s (SD = 39; M = 26% of Tmax, SD = 12). Additionally, they obtained mean 95% of VO2peak after 147 s (SD = 31; M = 62% of Tmax, SD = 8) and maintained it for 95 s (SD = 38; M = 38% of Tmax, SD = 8). These results suggest that 60-70% of Tmax is an appropriate exercise duration for a population of well trained cyclists to attain VO2peak during exercise at Pmax. However, due to intraparticipant variability in the temporal aspects of the VO2 response to exercise at Pmax, future research is needed to examine whether individual high-intensity interval training programs for well trained endurance athletes might best be prescribed according to an athlete's individual VO2 response to exercise at Pmax.     

Meaning of life as a protective factor of positive affect in acculturation: A resilience framework and a cross-cultural comparison

Although research has demonstrated a strong linkage between meaning of life and positive emotion, few studies have examined this association in the context of acculturation. The purpose of this study was to investigate the predictive effects of meaning of life and acculturative stressor on positive affect in a sample of Chinese international students in Australia and Hong Kong, and to compare these effects between the two groups. Four hundred mainland Chinese postgraduate students at six universities in Hong Kong and 227 Chinese international students at the University of Melbourne in Australia completed a questionnaire that included measures of acculturative stressor, meaning of life, positive affect, and demographic information. The analyses revealed that (1) meaning of life had a strong positive contribution to predict positive affect in acculturation, and acculturative stress had a negative impact on positive affect within both samples; (2) social interaction had a significant negative predictive effect on positive affect in both samples, and academic work served as a significant negative predictor of positive affect in the Hong Kong sample; and (3) meaning of life was found to mediate the relationship between acculturative stress and positive affect in both samples. The theoretical and practical implications of the study are discussed.     

Collagen-based brain microvasculature model in vitro using three-dimensional printed template

We present an engineered three-dimensional (3D) in vitro brain microvasculature system embedded within the bulk of a collagen matrix. To create a hydrogel template for the functional brain microvascular structure, we fabricated an array of microchannels made of collagen I using microneedles and a 3D printed frame. By culturing mouse brain endothelial cells (bEnd.3) on the luminal surface of cylindrical collagen microchannels, we reconstructed an array of brain microvasculature in vitro with circular cross-sections. We characterized the barrier function of our brain microvasculature by measuring transendothelial permeability of 40 kDa fluorescein isothiocyanate-dextran (Stoke''s radius of ∼4.5 nm), based on an analytical model. The transendothelial permeability decreased significantly over 3 weeks of culture. We also present the disruption of the barrier function with a hyperosmotic mannitol as well as a subsequent recovery over 4 days. Our brain microvasculature model in vitro, consisting of system-in-hydrogel combined with the widely emerging 3D printing technique, can serve as a useful tool not only for fundamental studies associated with blood-brain barrier in physiological and pathological settings but also for pharmaceutical applications.     

Confounding compression: the effects of posture,sizing and garment type on measured interface pressure in sports compression clothing

The purpose of this investigation was to measure the interface pressure exerted by lower body sports compression garments, in order to assess the effect of garment type, size and posture in athletes. Twelve national-level boxers were fitted with sports compression garments (tights and leggings), each in three different sizes (undersized, recommended size and oversized). Interface pressure was assessed across six landmarks on the lower limb (ranging from medial malleolus to upper thigh) as athletes assumed sitting, standing and supine postures. Sports compression leggings exerted a significantly higher mean pressure than sports compression tights (P < 0.001). Oversized tights applied significantly less pressure than manufacturer-recommended size or undersized tights (P < 0.001), yet no significant differences were apparent between different-sized leggings. Standing posture resulted in significantly higher mean pressure application than a seated posture for both tights and leggings (P < 0.001 and P = 0.002, respectively). Pressure was different across landmarks, with analyses revealing a pressure profile that was neither strictly graduated nor progressive in nature. The pressure applied by sports compression garments is significantly affected by garment type, size and posture assumed by the wearer.