Effects of Mediated Learning Experience, Tutor Support and Peer Collaborative Learning on Academic Achievement and IntellectualFunctioning among College Students

The main objective of this study was to investigate the effects of mediated learning experience, tutor support and peer collaborative learning on academic achievement and intellectual functioning. The sample comprised 111 first year engineering students (males=38, females=73, age range =16-23), who were randomly assigned to three learning conditions (Mediation: n=45, Tutor: n=36 and Peer: n=30). Data on academic achievement were based on mid-year and end-year examination results, while intellectual functioning was measured by the Ravens Advanced Progressive Matrices and the Organiser. Paired t-tests and Analysis of Covariances (ANCOVAs) were conducted to compare pre- and post- test academic and intellectual scores and comparison between the groups. Following a five-week intervention period, significant improvements in academic and intellectual functioning were found within the Mediation Group. The findings revealed that intervention involving mediation processes was more effective not only in enhancing students’ intellectual functioning but also improving their academic achievements

Proximal placement of lateral thigh skin markers reduces soft tissue artefact during normal gait using the Conventional Gait Model

A primary source of measurement error in gait analysis is soft tissue artefact. Hip and knee angle measurements, used regularly to guide clinical decisions, are particularly affected due to pervasive soft tissue on the femur. However, despite several studies of thigh marker artefact it remains unclear how lateral thigh marker height affects results using the popular Plug-in Gait model. We compared Plug-in Gait hip and knee joint angles for ten healthy subjects estimated using a proximal- and distal-third thigh marker placement and found significant differences. Relative to the distal marker, the proximal marker produced 37% less varus-valgus range and 50% less hip rotation range, suggesting that it produced less soft-tissue artefact in knee axis estimates. Knee flexion was also significantly affected due to knee centre displacement. Based on an analysis of the Plug-in Gait knee axis definition and two different numerical optimization of the thigh rotation offset parameter, we show that the proximal marker reduced sensitivity to soft-tissue artefact by decreasing collinearity between the points defining the femoral frontal plane and reducing anteroposterior movement between the knee and thigh markers. This study demonstrates that Plug-in Gait thigh marker height can have a considerable influence on outcomes used for clinical decision-making

Sleep and daytime sleepiness in methylphenidate medicated and un-medicated children with attention-deficit/hyperactivity disorder (ADHD)

Objective: Excessive daytime sleepiness due to any cause can result in various symptoms similar to those used for the diagnosis of attention deficit/hyperactivity disorder (ADHD). A common treatment for children diagnosed with ADHD is methylphenidate which is also used to treat excessive daytime sleepiness. This paper reports on a study which compared the perceived levels of daytime sleepiness and prevalence of sleep disorders in medicated and un-medicated children with ADHD. Method: The sample consisted of two matched groups of children who had been formally diagnosed with ADHD. One group (n=12) was taking immediate release methylphenidate twice daily, while the other group (n=11) had never, and were not currently, taking any medication. The two groups, as well as their parents, rated their levels of daytime sleepiness at three points in a single day. Results: Significantly higher levels of daytime sleepiness were reported by the parents of the un-medicated children between the hours of 13:00 and 15:00, compared to the medicated children. The medicated children became increasingly sleepier from the first to the second measurement in both the morning and afternoon. There was no significant difference in the number of sleep disorders/disruptions reported by the parents of either group. Conclusion: In a group of children with ADHD taking methylphenidate, there was a significant increase in  sleepiness a few hours after taking the medication, which may then have a significant impact on their learning. The data also imply that part of the mechanism of action of methylphenidate effects in these children may be by reduction of daytime sleepiness.Keywords: Attention Deficit Disorder with hyperactivity; Methylphenidate; Disorders of excessive somnolenc

RASSF4: Regulator of plasma membrane PI(4,5)P2.

Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is a negatively charged phospholipid that plays a major role in recruiting and regulating proteins at the plasma membrane-cytosol interface. In this issue, Chen et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201606047) demonstrate that RAS association domain family 4 (RASSF4) positively influences PI(4,5)P2 synthesis through ARF6-dependent regulation of PIP5K

Young athletes under pressure?

Regular participation in exercise has long been known to result in cardiovascular adaptation. Historically, the ‘athlete’s heart’ hypothesis has encouraged a dichotomised view of the heart’s adaptation to sport, depending on whether the physical activity was either of isotonic activity (runners and swimmers) resulting in ‘cardiomegaly’ or of isometric effort (wrestlers and shot putters, ie, ‘strength’ athletes) with clear peripheral adaptations and an ‘obvious increase in cardiac size’. Today, the classification of sports according to their physiological demands acknowledges a greater diversity of exposure, depending on the physical activity, with an emphasis on a ‘graded transition’ between the main categories: dynamic, static and impact. Still, our understanding of the determinants of structural and functional cardiovascular adaptation to exercise are limited, and the consequences for health remain a matter of debate

Ligand and membrane-binding behavior of the phosphatidylinositol transfer proteins PITPα and β

Phosphatidylinositol transfer proteins (PITPs) are believed to be lipid transfer proteins due to their ability to transfer either PI or PC between membrane compartments in vitro. However, the detailed mechanism of this transfer process is not fully established. To further understand the transfer mechanism of PITPs we examined the interaction of PITPs with membranes using dual polarization interferometry (DPI) which measures protein binding affinity on a flat immobilized lipid surface. In addition, a fluorescence resonance energy transfer (FRET)-based assay was also employed to monitor how quickly PITPs transfer their ligands to lipid vesicles. DPI analysis revealed that PITPβ had a higher affinity to membranes compared to PITPα. Furthermore, the FRET-based transfer assay revealed that PITPβ has a higher ligand transfer rate compared to PITPα. However, both PITPα and PITPβ demonstrated a preference for highly curved membrane surfaces during ligand transfer. In other words, ligand transfer rate was higher when the accepting vesicles were highly curved

The potential for using acoustic tracking to monitor the movement of the West Coast rock lobster Jasus lalandii

Although acoustic tracking has been used to study the movement of several species of clawed and spiny lobsters, only recent technological advances have provided sufficiently small transmitters to examine the utility of using acoustic tracking as a means to analyse the movement of relatively small spiny lobsters, such as Jasus lalandii. The effect of the transmitter on the mobility of J. lalandii was tested in aquarium experiments and was shown to have no influence on movement in three separate experiments. Thereafter, adult male rock lobsters (86–98mm carapace length) were tracked in field trials for up to 32 days at Betty's Bay (n = 4) and Hermanus (n = 5) off the Western Cape, South Africa. Tracking J. lalandii in the field using acoustic tags was successful, even in areas with dense kelp beds and rocky outcrops. The signal from the transmitters was readily detectable from the surface and subsequent use of underwater tracking equipment enabled visual confirmation of the position of the rock lobsters. Lobsters moved significantly longer distances (>45m day−1) in the first two days following tagging than during any subsequent time period (<10m day−1). This suggests that transmitter attachment and/or handling altered the movement pattern for the first 72 hours after tagging. During the period of observation, J. lalandii displayed classical nomadic behaviour

Feeling of knowing and restudy choices

Feeling-of-knowing judgments (FOK-Js) reflect people’s confidence that they would be able to recognize a currently unrecallable item. Although much research has been devoted to the factors determining the magnitude and accuracy of FOK-Js, much less work has addressed the issue of whether FOK-Js are related to any form of metacognitive control over memory processes. In the present study, we tested the hypothesis that FOK-Js are related to participants’ choices of which unrecallable items should be restudied. In three experiments, we showed that participants tend to choose for restudy items with high FOK-Js, both when they are explicitly asked to choose for restudy items that can be mastered in the restudy session (Exps. 1a and 2) and when such specific instructions are omitted (Exp. 1b). The study further demonstrated that increasing FOK-Js via priming cues affects restudy choices, even though it does not affect recall directly. Finally, Experiment 2 showed the strategy of restudying unrecalled items with high FOK-Js to be adaptive, because the efficacy of restudy is greater for these items than for items with low FOK-Js. Altogether, the present findings underscore an important role of FOK-Js for the metacognitive control of study operations

Revisiting the need for a literature search narrative: A brief methodological note

This is the author accepted manuscript. The final version is available from Wiley via the DOI inthis recordIn this method note, we question if the primary search strategy in a systematic review should be accompanied by a search narrative. A search narrative could offer a conceptual and contextual report on the search strategy, which we suggest might benefit the peer review of literature searches and increase engagement with, and discussion of, the literature search strategy from review stakeholders, topic experts, and lay users of research. Search narratives would also increase the transparency of decision-making in literature searching.Centre for Outcomes Research and Effectiveness (CORE)National Institute for Health Research (NIHR)Cochrane Common Mental Disorders (CCMD) Grou

Crystal structure of cobalt hydroxide carbonate Co2CO3(OH)(2): density functional theory and X-ray diffraction investigation

The cobalt carbonate hydroxide Co2CO3(OH)2 is a technologically important solid which is used as a precursor for the synthesis of cobalt oxides in a wide range of applications. It also has relevance as a potential immobilizer of the toxic element cobalt in the natural environment, but its detailed crystal structure is so far unknown. The structure of Co2CO3(OH)2 has now been investigated using density functional theory (DFT) simulations and powder X-ray diffraction (PXRD) measurements on samples synthesized via deposition from aqueous solution. Two possible monoclinic phases are considered, with closely related but symmetrically different crystal structures, based on those of the minerals malachite [Cu2CO3(OH)2] and rosasite [Cu1.5Zn0.5CO3(OH)2], as well as an orthorhombic phase that can be seen as a common parent structure for the two monoclinic phases, and a triclinic phase with the structure of the mineral kolwezite [Cu1.34Co0.66CO3(OH)2]. The DFT simulations predict that the rosasite-like and malachite-like phases are two different local minima of the potential energy landscape for Co2CO3(OH)2 and are practically degenerate in energy, while the orthorhombic and triclinic structures are unstable and experience barrierless transformations to the malachite phase upon relaxation. The best fit to the PXRD data is obtained using a rosasite model [monoclinic with space group P1121/n and cell parameters a = 3.1408 (4) Å, b = 12.2914 (17) Å, c = 9.3311 (16) Å and γ = 82.299 (16)°]. However, some features of the PXRD pattern are still not well accounted for by this refinement and the residual parameters are relatively poor. The relationship between the rosasite and malachite phases of Co2CO3(OH)2 is discussed and it is shown that they can be seen as polytypes. Based on the similar calculated stabilities of these two polytypes, it is speculated that some level of stacking disorder could account for the poor fit of the PXRD data. The possibility that Co2CO3(OH)2 could crystallize, under different growth conditions, as either rosasite or malachite, or even as a stacking-disordered phase intermediate between the two, requires further investigation