13 research outputs found
Quantification of particle aggregation rates for non-specific interactions:using the optomagnetic cluster experiment as a tool
Appropriateness of different pedagogical approaches to road safety education for children with Developmental Coordination Disorder (DCD)
Background In 2016, 29% of pedestrians killed or seriously injured on the roads in Great Britain were under 15 years of age. Children with Developmental Coordination Disorder (DCD), a chronic disorder affecting the acquisition and execution of motor skills, may be more vulnerable at the roadside than typically developing (TD) children. Current methods used to teach road safety are typically knowledge-based and do not necessarily improve behaviour in real traffic situations. Virtual reality road crossing tasks may be a viable alternative. Aims/Methods The present study aimed to test the road crossing accuracy of children with and without DCD in virtual reality tasks that varied the viewpoint to simulate the teaching methods currently used in road safety educational programmes. Twenty-one children with DCD and twenty-one age and gender matched TD peers were required to locate the safest road crossing sites in two conditions: allocentric (aerial viewpoint) and egocentric (first-person viewpoint). Procedures/Outcomes All children completed both conditions and were required to navigate either themselves or an avatar across the road using the safest crossing route. The primary outcome was accuracy defined as the number of trials, out of 10, on which the child successfully identified and used the safest crossing route. Results/Conclusions Children with DCD performed equally poorly in both conditions, while TD children were significantly more accurate in the egocentric condition. This difference cannot be explained by self-reported prior road crossing education, practice or confidence. Implications While TD children may benefit from the development of an egocentric virtual reality road crossing task, multimodal methods may be needed to effectively teach road safety to children with DCD
Possible origins of macroscopic left-right asymmetry in organisms
I consider the microscopic mechanisms by which a particular left-right (L/R)
asymmetry is generated at the organism level from the microscopic handedness of
cytoskeletal molecules. In light of a fundamental symmetry principle, the
typical pattern-formation mechanisms of diffusion plus regulation cannot
implement the "right-hand rule"; at the microscopic level, the cell's
cytoskeleton of chiral filaments seems always to be involved, usually in
collective states driven by polymerization forces or molecular motors. It seems
particularly easy for handedness to emerge in a shear or rotation in the
background of an effectively two-dimensional system, such as the cell membrane
or a layer of cells, as this requires no pre-existing axis apart from the layer
normal. I detail a scenario involving actin/myosin layers in snails and in C.
elegans, and also one about the microtubule layer in plant cells. I also survey
the other examples that I am aware of, such as the emergence of handedness such
as the emergence of handedness in neurons, in eukaryote cell motility, and in
non-flagellated bacteria.Comment: 42 pages, 6 figures, resubmitted to J. Stat. Phys. special issue.
Major rewrite, rearranged sections/subsections, new Fig 3 + 6, new physics in
Sec 2.4 and 3.4.1, added Sec 5 and subsections of Sec
Bevorderen van communicatie over leerinhoud tussen groepsleden tijdens projectwerk bij natuurkunde
The role of selective venous sampling in the management of persistent hyperparathyroidism revisited
Introduction: Localization studies are mandatory prior to revision surgery in patients with persistent hyperparathyroidism in order to improve surgical outcome and reduce the risk of lengthy explorations. However, in this case, noninvasive localization studies are reported to have a poor sensitivity. The aim of our study is to determine the accuracy of selective venous sampling (SVS) for parathyroid hormone (PTH) in localizing residual hyperactive parathyroid glands in patients with persistent or recurrent hyperparathyroidism. Patients and methods: We retrospectively evaluated the localizing accuracy of 20 PTH SVS performed prior to revision surgery in 18 patients with persistent or recurrent primary hyperparathyroidism (n=11) or autonomous (tertiary) hyperparathyroidism (n=7). Tc99m-methoxy-isobutyle-isonitrile (MIBI)-single photon emission computed tomography (SPECT) was also performed in all patients prior to revision surgery. Operative and pathological data were obtained from hospital records. Results: The SVS was able to accurately localize 15 of the 20 pathological glands removed at revision surgery, representing a sensitivity of 75%. This sensitivity is significantly higher than that of Tc99m-MIBI-SPECT, which was only 30% (P=0.012). Conclusion: Our findings demonstrate that SVS is a valuable localization study in patients with persistent or recurrent hyperparathyroidism, with a sensitivity significantly higher than that of Tc99m-MIBI-SPECT. Our data suggest that SVS represents a useful addition to the preoperative workup of these patients prior to revision surgery.Molecular tumour pathology - and tumour genetic
How to maximize the kwh/kwp ratio : simulations of single-axis tracking in bifacial systems
Medical Treatment of Cushing's Disease with Pasireotide Mono- or Combination Therapy with Cabergoline and Ketoconazole Modulates Somatostatin Receptor Subtype Expression on Corticotroph Tumor Cells
Diabetes mellitus: pathophysiological changes and therap
Gender-dependent effects of high-fat lard diet on cardiac function in C57Bl/6J mice.
Item does not contain fulltextIncreased availability of fatty acids released from insulin-resistant adipose tissue may lead to excess fatty acid uptake in nonadipose organs, including the heart. Accumulation of toxic fatty acid intermediates may affect cardiac function. Our aim was to identify to which extent high-fat diet feeding leads to alterations in cardiac function and whether this depends on gender and (or) duration of high-fat diet feeding. Male and female C57Bl/6J mice (n = 8 per group) of 12 to 16 weeks old were fed a low-fat (10% energy) or high-fat (45% energy) lard diet for 6 or 12 weeks. Plasma lipid levels, echocardiography, and left ventricular pressure-volume relationships were obtained at 2, 1, and 0 weeks before termination, respectively. In both male and female mice, the high-fat diet increased body weight and plasma lipid content. At 10 weeks, significant increases were observed for plasma total cholesterol (males: +44%; females: +86%), phospholipids (+16% and +34%), and triglycerides (+27% and +53%) (all p < 0.001). In male mice, but not in female mice, the high-fat diet significantly affected cardiac function at 12 weeks with increased end-systolic volume (25.4 +/- 6.2 vs. 17.0 +/- 6.7 microL, p < 0.05), increased end-systolic pressure (72.1 +/- 6.9 vs. 63.6 +/- 6.9 mm Hg, p < 0.01), and decreased ejection fraction (61.2% +/- 4.5% vs. 68.1% +/- 3.7%, p < 0.01), indicating reduced systolic function. Multiple linear regression analysis indicated a significant diet-gender interaction for end-systolic volume and ejection fraction. In conclusion, high-fat diet feeding increased body weight and plasma lipid levels in male and in female mice, but resulted in impairment of cardiac function only in males.1 april 201