Assessment worlds colliding? Negotiating between discourses of assessment on an online open course

Using the badged open course, Taking your first steps into Higher Education, this case study examines how assessment on online open courses draws on concepts of assessment used within formal and informal learning. Our experience was that assessment used within open courses, such as massive open online courses, is primarily determined by the requirements of quality assurance processes to award a digital badge or statement of participation as well as what is technologically possible. However, this disregards much recent work in universities that use assessment in support of learning. We suggest that designers of online open courses should pay greater attention to the relationship of assessment and learning to improve participant course completion

Prevalence, Predictors & Prevention of Motion Sickness in Zero-G Parabolic Flights

INTRODUCTION Zero-G parabolic flight reproduces the weightlessness of space for short periods of time. However motion sickness may affect some fliers. The aim was to assess the extent of this problem and to find possible predictors and modifying factors. METHODS Airbus Zero-G flights consist of 31 parabolas performed in blocks. Each parabola consisted of 20s 0g sandwiched by 20s hypergravity of 1.5-1.8g. The survey covered n=246 person-flights (193 Males 53 Females), aged (M+/-SD) 36.0+/-11.3 years. An anonymous questionnaire included motion sickness rating (1=OK to 6=Vomiting), Motion Sickness Susceptibility Questionnaire (MSSQ), anti-motion sickness medication, prior Zero-G experience, anxiety level, and other characteristics. RESULTS Participants had lower MSSQ percentile scores 27.4+/-28.0 than the population norm of 50. Motion sickness was experienced by 33% and 12% vomited. Less motion sickness was predicted by older age, greater prior Zero-G flight experience, medication with scopolamine, lower MSSQ scores, but not gender nor anxiety. Sickness ratings in fliers pre-treated with scopolamine (1.81+/-1.58) were lower than for non-medicated fliers (2.93+/-2.16), and incidence of vomiting in fliers using scopolamine treatment was reduced by half to a third. Possible confounding factors including age, sex, flight experience, MSSQ, could not account for this. CONCLUSION Motion sickness affected one third of Zero-G fliers, despite being intrinsically less motion sickness susceptible compared to the general population. Susceptible individuals probably try to avoid such a provocative environment. Risk factors for motion sickness included younger age and higher MSSQ scores. Protective factors included prior Zero-G flight experience (habituation) and anti-motion sickness medication

VEGF guides angiogenic sprouting utilizing endothelial tip cell filopodia

Vascular endothelial growth factor (VEGF-A) is a major regulator of blood vessel formation and function. it controls several processes in endothelial cells, such as proliferation, survival, and migration, but it is not known how these are coordinately regulated to result in more complex morphogenetic events, such as tubular sprouting, fusion, and network formation. We show here that VEGF-A controls angiogenic sprouting in the early postnatal retina by guiding filopodial extension from specialized endothelial cells situated at the tips of the vascular sprouts. The tip cells respond to VEGF-A only by guided migration; the proliferative response to VEGF-A occurs in the sprout stalks. These two cellular responses are both mediated by agonistic activity of VEGF-A on VEGF receptor 2. Whereas tip cell migration depends on a gradient of VEGF-A, proliferation is regulated by its concentration. Thus, vessel patterning during retinal angiogenesis depends on the balance between two different qualities of the extracellular VEGF-A distribution, which regulate distinct cellular responses in defined populations of endothelial cells

Pretreatment of citrus by-products affects polyphenol recovery:a review

A large amount of citrus waste is generated annually. This waste is of great economic worth, since it contains high levels of polyphenols, which have attracted scientific interest due to their potent antimicrobial and antiradical activities. Pretreatment is a crucial step that precedes the extraction process and influences the yields and quality of polyphenols. This review emphasizes the effect of different drying processes, such as freeze drying, hot-air drying, vacuum drying, microwave drying, infrared drying, and high-speed drying, on the polyphenol retention in citrus by-products. Further treatments of the dried citrus by-products for assisting the liberation of bound polyphenols are also provided and comprehensively discussed

Two-phase gravity currents in porous media

We develop a model describing the buoyancy-driven propagation of two-phase gravity currents, motivated by problems in groundwater hydrology and geological storage of carbon dioxide (CO2). In these settings, fluid invades a porous medium saturated with an immiscible second fluid of different density and viscosity. The action of capillary forces in the porous medium results in spatial variations of the saturation of the two fluids. Here, we consider the propagation of fluid in a semi-infinite porous medium across a horizontal, impermeable boundary. In such systems, once the aspect ratio is large, fluid flow is mainly horizontal and the local saturation is determined by the vertical balance between capillary and gravitational forces. Gradients in the hydrostatic pressure along the current drive fluid flow in proportion to the saturation-dependent relative permeabilities, thus determining the shape and dynamics of two-phase currents. The resulting two-phase gravity current model is attractive because the formalism captures the essential macroscopic physics of multiphase flow in porous media. Residual trapping of CO2 by capillary forces is one of the key mechanisms that can permanently immobilize CO2 in the societally important example of geological CO2 sequestration. The magnitude of residual trapping is set by the areal extent and saturation distribution within the current, both of which are predicted by the two-phase gravity current model. Hence the magnitude of residual trapping during the post-injection buoyant rise of CO2 can be estimated quantitatively. We show that residual trapping increases in the presence of a capillary fringe, despite the decrease in average saturation

Gendered play behaviours in autistic and non-autistic children: A population-based cohort study

Gender-typical play is observed throughout childhood for non-autistic children. However, there has been limited research into the gender typicality of autistic children’s play compared to that of non-autistic children. In a longitudinal population-based cohort, we compared gendered play behaviours in autistic and non-autistic children using standardised parent-report (30, 42 and 57 months) and child-report (8 years) data (N = 11,251). We observed no difference in gendered play behaviours between girls with or without autism at any time point. Autistic and non-autistic boys did not differ in the gender typicality of their play when aged 30 months, but the play of autistic boys appeared less masculine than that of non-autistic boys (β = −1.1, 95% confidence interval = −2.1 to −0.2; and β = −2.6, 95% confidence interval = −4.7 to −0.5) at 42 and 57 months. Autistic boys also self-reported less masculine play behaviours than non-autistic boys at 8 years of age (β = −3.4, 95% confidence interval = −6.6 to −0.2). We found that autistic boys’ play was less gender typical than that of non-autistic boys in middle and later childhood. Our findings highlight the importance of examining gendered play behaviours in a developmental context and have relevance for understanding the development of gender identity in autism. Lay abstract: Non-autistic children tend to show gendered patterns of play behaviours – boys are more likely to play with ‘masculine’ toys, and girls are more likely to play with ‘feminine’ toys. However, little is known about whether autistic children follow these patterns as well. We looked at the masculinity and femininity of autistic and non-autistic children’s play behaviours at multiple time points. Parents reported their children’s play behaviours at ages 30, 42 and 57 months, and children reported their own play behaviours at 8 years old. We found no difference between autistic and non-autistic girls, who both showed more feminine play behaviours as they got older. Autistic boys’ play behaviours were reported as less masculine than non-autistic boys at 42 and 57 months, and at 8 years old. We also found that non-autistic boys’ play tended to become more masculine as they got older, but this was not the case for autistic boys. Our findings suggest that differences in autistic and non-autistic boys’ play behaviours may develop at around 42 months old

Orientation and symmetry control of inverse sphere magnetic nanoarrays by guided self-assembly

Inverse sphere shaped Ni arrays were fabricated by electrodeposition on Si through the guided self-assembly of polystyrene latex spheres in Si/SiO2 patterns. It is shown that the size commensurability of the etched tracks is critical for the long range ordering of the spheres. Moreover, noncommensurate guiding results in the reproducible periodic triangular distortion of the close packed self-assembly. Magnetoresistance measurements on the Ni arrays were performed showing room temperature anisotropic magnetoresistance of 0.85%. These results are promising for self-assembled patterned storage media and magnetoresistance devices