Evidence for data missing at random in youth physical activity monitoring research

This study examined whether or not activity monitor data collected as part of a typical 7-day physical activity (PA) measurement protocol can be expected to be missing at random. A total of 315 participants (9–18 years) each wore a SenseWear Armband monitor for 7 consecutive days. Participants were classified as “compliant” (86 boys and 124 girls) if they had recorded accelerometer data during 70% or more of the predefined awake time (7 AM–10 PM) on four different days; and “non-compliant” (44 boys and 51 girls) when not meeting these criteria. Linear mixed models were used to examine differences in energy expenditure (EE) levels by compliance across 10 different time periods. The results indicated that non-compliant girls were older (13.4 ± 2.9 vs. 12.2 ± 2.5) and taller (156.8 ± 10.3 vs. 152.8 ± 11.3) than their same gender compliant peers (P < .05). Comparisons of EE rates at segmented portions of the day revealed no differences between compliant and non-compliant groups (P ≥ .05). Differences in EE ranged from ?0.32 kcal · kg^?1 · h^?1 (before school time) to 0.62 kcal · kg^?1 · h^?1 (physical education class) in boys and ?0.39 kcal · kg^?1 · h^?1 (transportation from school) to 0.37 kcal · kg^?1 · hour^?1 (recess) in girls. The results showed that compliant and non-compliant individuals differed in a few demographic characteristics but exhibited similar activity patterns. This suggests that data were considered to be missing at random, but additional work is needed to confirm this observation in a representative sample of children using other types of activity monitors and protocols.     

Conserving indigenous knowledge as the key to the current and future use of traditional vegetables

Indigenous knowledge erodes rapidly. When the loss of this knowledge negatively affects the lives and health of traditionally living rural communities, a drive to conserve indigenous knowledge becomes vital. This article argues that the transfer of indigenous knowledge on traditional vegetables will ensure the availability and utilisation of this important food source for resource-poor rural communities. Data collected on the present use of traditional vegetables at a rural Xhosa village in the Eastern Cape Province of South Africa documented indigenous practices of traditional vegetable use and measured attitudes and perceptions of young women. Findings revealed that although traditional vegetables are readily available, there is a decline in the use of traditional vegetables in this village. Since the loss of associated indigenous knowledge is a reality, and in view of the negative attitude towards traditional vegetables, future use of this valuable food source is threatened. The transfer of the associated indigenous knowledge holds the key to the potential future use of traditional vegetables. Altered perceptions of traditional vegetables are crucial for the conservation of the associated indigenous knowledge. As a result awareness campaigns to promote the use of traditional vegetables, related nutritional education, including proper cooking and preservation techniques are necessary.     

Effect of iron deficiency on developing rat brain

Iron deficiency evolves, slowly through several stages. Early iron deficiency caused a depletion in iron stores as shown by a reduction in the levels of hepatic non heme iron (44%) in the 7 days old pups born to iron deficient mothers. The hemoglobin levels and PCV (packed cell volume) were significantly reduced only after the age of three weeks. The activities of GABA (γ-amino butyric acid) shunt enzymes viz. GDH, GAD and GABA-T (glutamate dehydrogenase, glutamate decarboxylase and GABA-transaminase, respectively) and GABA content were found to decrease during gestation and/or lactation iron deficiency at 1 week (wk), 2wk, 3wk and 4wk of age in the developing rat brains. However GABA binding showed a significant increase at different age groups. The iron deficiency during lactational exposure showed significant alteration in most of the parameters only at the age of 3 weeks onwards. On rehabilitation with iron supplemented diet for 2 weeks, these altered parameters could not attain corresponding control values. A prolonged iron deficiency causing alterations in GABA may lead to neurological and behavioral alterations.     

Reading expressively and understanding thoroughly: An examination of prosody in adults with low literacy skills

The purpose of the current study was to explore the relationship between prosody, which is the expressive quality of reading out loud, and reading comprehension in adults with low literacy skills compared to skilled readers. All participants read a passage orally, and we extracted prosodic measures from the recordings. We examined pitch changes and how long readers paused at various points while reading. Finally, for the adults with low literacy skills, we collected information on decoding, word recognition, and reading comprehension. We found several interesting results. First, adults with low literacy skills paused longer than skilled readers and paused at a substantially greater number of punctuation marks. Second, while adults with low literacy skills do mark the end of declarative sentences with a pitch declination similar to skilled readers, their readings of questions lack a change in pitch. Third, decoding and word recognition skills were related to pauses while reading; readers with lower skills made longer and more frequent and inappropriate pauses. Finally, pausing measures explained a significant amount of variance in reading comprehension among the adults with low literacy skills.     

The impact of workforce agility on organizational memory

Existing literature has generally focused on organizational memory (OM) and workforce agility. Yet, less concentration has been devoted to the impact of workforce agility on OM. This research proposed a model that studies the impact of workforce agility on declarative OM and procedural OM. The model focused on aspects related to proactivity, adaptability, and resiliency. The study targeted the cell phone industry in Jordan. The study sample included 430 individuals involved in managerial and professional knowledge positions in mobile communications companies in Jordan. The article concluded that a proactive workforce has a significant impact on declarative OM and proactivity also improves procedural OM. Consequently, practical implications for managers, and suggested future research are presented.     

Instructional design for advanced learners: Establishing connections between the theoretical frameworks of cognitive load and deliberate practice

Cognitive load theory (CLT) has been successful in identifying instructional formats that are more effective and efficient than conventional problem solving in the initial, novice phase of skill acquisition. However, recent findings regarding the “expertise reversal effect” have begun to stimulate cognitive load theorists to broaden their horizon to the question of how instructional design should be altered as a learner's knowledge increases. To answer this question, it is important to understand how expertise is acquired and what fosters its development. Expert performance research, and, in particular, the theoretical framework of deliberate practice have given us a better understanding of the principles and activities that are essential in order to excel in a domain. This article explores how these activities and principles can be used to design instructional formats based on CLT for higher levels of skills mastery. The value of these formats for e-learning environments in which learning tasks can be adaptively selected on the basis of online assessments of the learner's level of expertise is discussed. In their preparation of this article, the first and last authors were supported by an Internationalization grant from the Netherlands Organization for Scientific Research (NWO, The Hague, project number 411-01-010).