FUNBOE - Follow-Up Nucleate Boiling On-flight Experiment: A Systematic Study of Nucleate Boiling in Microgravity

Utah State University’s Get Away Special (GAS) team was awarded the opportunity to participate in Reduced Gravity Student Flight Opportunities program administered by NASA. Six members of the GAS team will fly in a specialized jet which will simulate microgravity where the experiment can be performed in 30 second intervals. The purpose of the experiment is to determine the properties of nucleate boiling of water in weightlessness. The experiment will be monitored with temperature sensors, accelerometers, and high definition cameras and the results will be analyzed frame by frame. This will provide important information related to the dynamics of heat transfer using thin wire heating elements in microgravity. Under these controlled conditions, the boiling dynamics will be under specific scrutiny. Additionally, other observations related to varying power inputs and the effects of alternate surface geometries of the platinum wire will be made. The GAS team flies June 17-26, 2010 at Johnson Space Center, Houston, TX

Do gadolinium-based contrast agents alter 23Na T1 relaxivity in glioma?

Incomplete fluid suppression on fluid-attenuated inversion-recovery 23Na-MRI (IR-23Na-MRI) was observed in three patients undergoing IR-23Na-MRI after gadolinium contrast injection, as part of a brain tumour imaging study. To evaluate this, 23Na-MRI T1 maps were acquired before and after injection of a gadolinium-based contrast agent on a grade IV glioma (GBM) patient, which showed a statistically significant change of 23Na-MRI T1 within the peritumoral oedema (p=0.0095). Gadolinium contrast-enhanced 23Na-MRI could potentially add further applications for sodium imaging and probe tumour tissue structure in new ways to investigate proliferation and treatment response

Whole number thinking, learning and development: neuro-cognitive, cognitive and developmental approaches

The participants of working group 2 presented a broad range of studies, 11 papers in total, related to whole number learning representing research groups from 11 countries as follows. Two large cross-sectional studies focused on developmental aspects of young children’s number learning provide a lens for re-examining ‘traditional’ features of number acquisition. van den Heuvel-Panhuizen (the Netherlands) presented a co-authored paper with Elia (Cyprus; Elia and van den Heuvel-Panhuizen 2015) on a cross-cultural study of kindergartners’ number competence focused on counting, additive and multiplicative thinking. Second, Milinković (2015) examined the development of young Serbian children’s initial understanding of representations of whole numbers and counting strategies in a large study of 3- to 7-year-olds. Children’s invented (formal) representations such as set representation and the number line were found to be limited in their recordings. In a South African study focused on early counting and addition, Roberts (2015) directs attention to the role of teachers by providing a framework to support teachers’ interpretation of young disadvantaged learners’ representations of number when engaging with whole number additive tasks. Some papers reflected the increasing role of neuroscientific concepts and methodologies utilised in research on WNA learning and development. Sinclair and Coles (2015) drew upon neuroscientific research to highlight the significant role of symbol-to-symbol connections and the use of fingers and touch counting exempli- fied by the TouchCounts iPad app. Gould (2015) reported aspects of a large Australian large study of children in the first years of schooling aimed at improving numeracy and literacy in disadvantaged communities. A case study exemplified how numerals were identified by relying on a mental number line by using location to retrieve number names. This raised the question addressed in the neuroscientific work of Dehaene and other papers focused on individual differences in how the brain processes numbers. The Italian PerContare1 project (Baccaglini-Frank 2015) built upon the collaboration between cognitive psychologists and mathematics educators, aimed at developing teaching strategies for preventing and addressing early low achievement in arithmetic. It takes an innovative approach to the development of number sense that is grounded upon a kinaesthetic and visual-spatial approach to part-whole relationships. Mulligan and Woolcott (2015) provided a discussion paper on the underlying nature of number. They presented a broader view of mathematics learning (including WNA) as linked to spatial interaction with the environment; the concept of connectivity across concepts and the development of underlying pattern and structural relationships are central to their approach

Species-diagnostic microsatellite loci for the fig wasp genus Pegoscapus

To obtain tools for the estimation of inbreeding and assignment of offspring to matrilines, we developed 13 microsatellite loci from the fig wasps that pollinate Ficus obtusifolia. Based on morphological studies, it was thought that a single species (Pegoscapus hoffmeyer) pollinated this fig. However, our data revealed the presence of two coexisting cryptic species. Several diagnostic microsatellite markers may be used to distinguish these two cryptic species. The new microsatellites can be used across a wide range of fig-pollinating wasp species for both evolutionary and population genetic studies

Bridging Time Scales in Cellular Decision Making with a Stochastic Bistable Switch

Cellular transformations which involve a significant phenotypical change of the cell's state use bistable biochemical switches as underlying decision systems. In this work, we aim at linking cellular decisions taking place on a time scale of years to decades with the biochemical dynamics in signal transduction and gene regulation, occuring on a time scale of minutes to hours. We show that a stochastic bistable switch forms a viable biochemical mechanism to implement decision processes on long time scales. As a case study, the mechanism is applied to model the initiation of follicle growth in mammalian ovaries, where the physiological time scale of follicle pool depletion is on the order of the organism's lifespan. We construct a simple mathematical model for this process based on experimental evidence for the involved genetic mechanisms. Despite the underlying stochasticity, the proposed mechanism turns out to yield reliable behavior in large populations of cells subject to the considered decision process. Our model explains how the physiological time constant may emerge from the intrinsic stochasticity of the underlying gene regulatory network. Apart from ovarian follicles, the proposed mechanism may also be of relevance for other physiological systems where cells take binary decisions over a long time scale.Comment: 14 pages, 4 figure

Photoswitchable diacylglycerols enable optical control of protein kinase C.

Increased levels of the second messenger lipid diacylglycerol (DAG) induce downstream signaling events including the translocation of C1-domain-containing proteins toward the plasma membrane. Here, we introduce three light-sensitive DAGs, termed PhoDAGs, which feature a photoswitchable acyl chain. The PhoDAGs are inactive in the dark and promote the translocation of proteins that feature C1 domains toward the plasma membrane upon a flash of UV-A light. This effect is quickly reversed after the termination of photostimulation or by irradiation with blue light, permitting the generation of oscillation patterns. Both protein kinase C and Munc13 can thus be put under optical control. PhoDAGs control vesicle release in excitable cells, such as mouse pancreatic islets and hippocampal neurons, and modulate synaptic transmission in Caenorhabditis elegans. As such, the PhoDAGs afford an unprecedented degree of spatiotemporal control and are broadly applicable tools to study DAG signaling

Democratic Teacher Education Practices

[Living reference work entry] This entry provides an insight into the turbulent and recently disappointing events in the history of Design and Technology (D&T) teacher education in England over the last 150 years. It is a complex journey that needs to include a review of the generic history of teacher education in England, the differing educational needs of children, the changing role of D&T as a school curriculum subject, the requirements for an appropriately trained workforce to meet the economic needs of the country, and how various government educational initiatives and interventions (Gillard 2018) have affected how teachers in general and D&T teachers in particular have been and still are trained today. All these factors are inseparably intertwined. Therefore, this entry discusses them all together in chronological date order

HNPCC: Six new pathogenic mutations

BACKGROUND: Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant disease with a high risk for colorectal and endometrial cancer caused by germline mutations in DNA mismatch-repair genes (MMR). HNPCC accounts for approximately 2 to 5% of all colorectal cancers. Here we present 6 novel mutations in the DNA mismatch-repair genes MLH1, MSH2 and MSH6. METHODS: Patients with clinical diagnosis of HNPCC were counselled. Tumor specimen were analysed for microsatellite instability and immunohistochemistry for MLH1, MSH2 and MSH6 protein was performed. If one of these proteins was not detectable in the tumor mutation analysis of the corresponding gene was carried out. RESULTS: We identified 6 frameshift mutations (2 in MLH1, 3 in MSH2, 1 in MSH6) resulting in a premature stop: two mutations in MLH1 (c.2198_2199insAACA [p.N733fsX745], c.2076_2077delTG [p.G693fsX702]), three mutations in MSH2 (c.810_811delGT [p.C271fsX282], c.763_766delAGTGinsTT [p.F255fsX282], c.873_876delGACT [p.L292fsX298]) and one mutation in MSH6 (c.1421_1422dupTG [p.C475fsX480]). All six tumors tested for microsatellite instability showed high levels of microsatellite instability (MSI-H). CONCLUSIONS: HNPCC in families with MSH6 germline mutations may show an age of onset that is comparable to this of patients with MLH1 and MSH2 mutations

Getting to the Root of Fine Motor Skill Performance in Dentistry: Brain Activity During Dental Tasks in a Virtual Reality Haptic Simulation.

BACKGROUND: There is little evidence considering the relationship between movement-specific reinvestment (a dimension of personality which refers to the propensity for individuals to consciously monitor and control their movements) and working memory during motor skill performance. Functional near-infrared spectroscopy (fNIRS) measuring oxyhemoglobin demands in the frontal cortex during performance of virtual reality (VR) psychomotor tasks can be used to examine this research gap. OBJECTIVE: The aim of this study was to determine the potential relationship between the propensity to reinvest and blood flow to the dorsolateral prefrontal cortices of the brain. A secondary aim was to determine the propensity to reinvest and performance during 2 dental tasks carried out using haptic VR simulators. METHODS: We used fNIRS to assess oxygen demands in 24 undergraduate dental students during 2 dental tasks (clinical, nonclinical) on a VR haptic simulator. We used the Movement-Specific Reinvestment Scale questionnaire to assess the students' propensity to reinvest. RESULTS: Students with a high propensity for movement-specific reinvestment displayed significantly greater oxyhemoglobin demands in an area associated with working memory during the nonclinical task (Spearman correlation, rs=.49, P=.03). CONCLUSIONS: This small-scale study suggests that neurophysiological differences are evident between high and low reinvesters during a dental VR task in terms of oxyhemoglobin demands in an area associated with working memory

Selection at a single locus leads to widespread expansion of toxoplasma gondii lineages that are virulent in mice

The determinants of virulence are rarely defined for eukaryotic parasites such as T. gondii, a widespread parasite of mammals that also infects humans, sometimes with serious consequences. Recent laboratory studies have established that variation in a single secreted protein, a serine/threonine kinase known as ROPO18, controls whether or not mice survive infection. Here, we establish the extent and nature of variation in ROP18among a collection of parasite strains from geographically diverse regions. Compared to other genes, ROP18 showed extremely high levels of diversification and changes in expression level, which correlated with severity of infection in mice. Comparison with an out-group demonstrated that changes in the upstream region that regulates expression of ROP18 led to an historical increase in the expression and exposed the protein to diversifying selective pressure. Surprisingly, only three atypically distinct protein variants exist despite marked genetic divergence elsewhere in the genome. These three forms of ROP18 are likely adaptations for different niches in nature, and they confer markedly different virulence to mice. The widespread distribution of a single mouse-virulent allele among geographically and genetically disparate parasites may have consequences for transmission and disease in other hosts, including humans