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Visual Preference for Curvature and Art Paintings: Some Data
Get PDFThe visual preference for curvature is a human phenomenon that has been found on numerous studies.
After the success of Bar and Neta (2006) on finding the preference for curvature using sharp-angled and
curved versions of the same object, our research group replicated those results using the same stimuli but
with a forced choice task in an approach-avoidance framework. With this new task, the effect of
preference for curvature was also found in short exposure times: 40 and 80 miliseconds. Next we decided
to apply the same paradigm but using art paintings. Pairs of similar abstract art images –a curved version
and a sharp-angled one- were created. We used both color and black and white paintings. Only a weak
effect was found in the color pairs with 40 ms exposure time. After these results we have revised the
paradigm: (a) modifiyng some edges in sharp-angled images to have a more analogous set of curved
images and (b) using a Likert scale with the aim to simulate art appreciation
Campylobacter jejuni biofilms contain extracellular DNA and are sensitive to DNase I treatment
Get PDFBiofilms make an important contribution to survival and transmission of bacterial pathogens in the food chain. The human pathogen Campylobacter jejuni is known to form biofilms in vitro in food chain-relevant conditions, but the exact roles and composition of the extracellular matrix are still not clear. Extracellular DNA has been found in many bacterial biofilms and can be a major component of the extracellular matrix. Here we show that extracellular DNA is also an important component of the C. jejuni biofilm when attached to stainless steel surfaces, in aerobic conditions and on conditioned surfaces. Degradation of extracellular DNA by exogenous addition of DNase I led to rapid biofilm removal, without loss of C. jejuni viability. Following treatment of a surface with DNase I, C. jejuni was unable to re-establish a biofilm population within 48 h. Similar results were obtained by digesting extracellular DNA with restriction enzymes, suggesting the need for high molecular weight DNA. Addition of C. jejuni genomic DNA containing an antibiotic resistance marker resulted in transfer of the antibiotic resistance marker to susceptible cells in the biofilm, presumably by natural transformation. Taken together, this suggest that eDNA is not only an important component of C. jejuni biofilms and subsequent food chain survival of C. jejuni, but may also contribute to the spread of antimicrobial resistance in C. jejuni. The degradation of extracellular DNA with enzymes such as DNase I is a rapid method to remove C. jejuni biofilms, and is likely to potentiate the activity of antimicrobial treatments and thus synergistically aid disinfection treatments
A PAS domain-containing regulator controls flagella-flagella interactions in Campylobacter jejuni
Get PDFThe bipolar flagella of the foodborne bacterial pathogen Campylobacter jejuni confer motility, which is essential for virulence. The flagella of C. jejuni are post-translationally modified, but how this process is controlled is not well understood. In this work, we have identified a novel PAS-domain containing regulatory system, which modulates flagella-flagella interactions in C. jejuni. Inactivation of the cj1387c gene, encoding a YheO-like PAS6 domain linked to a helix-turn-helix domain, resulted in the generation of a tightly associated “cell-train” morphotype, where up to four cells were connected by their flagella. The morphotype was fully motile, resistant to vortexing, accompanied by increased autoagglutination, and was not observed in aflagellated cells. The Δcj1387c mutant displayed increased expression of the adjacent Cj1388 protein, which comprises of a single endoribonuclease L-PSP domain. Comparative genomics showed that cj1387c (yheO) orthologs in bacterial genomes are commonly linked to an adjacent cj1388 ortholog, with some bacteria, including C. jejuni, containing another cj1388-like gene (cj0327). Inactivation of the cj1388 and cj0327 genes resulted in decreased autoagglutination in Tween-20-supplemented media. The Δcj1388 and Δcj0327 mutants were also attenuated in a Galleria larvae-based infection model. Finally, substituting the sole cysteine in Cj1388 for serine prevented Cj1388 dimerization in non-reducing conditions, and resulted in decreased autoagglutination in the presence of Tween-20. We hypothesize that Cj1388 and Cj0327 modulate post-translational modification of the flagella through yet unidentified mechanisms, and propose naming Cj1387 the Campylobacter Flagella Interaction Regulator CfiR, and the Cj1388 and Cj0327 protein as CfiP and CfiQ, respectively
Understanding, evidencing and promoting adolescent wellbeing: An emerging agenda for schools
Get PDFThe well-being of young people is of considerable concern with many initiatives targeting the health behaviors of this population. Educators are among the professional groups being challenged to understand, evidence, and enhance childhood well-being. Working with a case study U.K. school adolescent subjective well-being (SWB) was examined through the administering of the Personal Wellbeing Index–School Children (PWI-SC; n = 840) and focus groups with pupils (n = 18). PWI-SC results suggest significant differences in personal well-being between school years (p < .001). Focus group data indicate that transitional periods associated with adolescence, feeling unsafe, and anxiety over the future were linked to a lowering of SWB. Asset-based well-being strategies that promote health literacy and build on the resources of young people and local communities are considered as a means for schools to promote well-being
An investigation of the acute effects of oligofructose enriched inulin on subjective wellbeing, mood and cognitive performance
Get PDFAbstract: Inulin is a natural food component found in many plants that are part of the human
diet (e.g., leeks, onions, wheat, garlic, chicory and artichokes). It is added to many foods and
is used to increase dietary fibre, replace fats or carbohydrates, and as a prebiotic (a stimulant of
beneficial bacteria in the colon). Oligofructose, which is also present in these foods, produces similar
effects and most research has used a combination of these products. A previous study (Smith, 2005)
investigated the effects of regular consumption of oligofructose-enriched inulin on wellbeing, mood,
and cognitive performance in humans. The results showed that oligofructose-enriched inulin had
no negative effects but that it did not improve wellbeing, mood, or performance. The aim of the
present study was to examine the acute effects of oligofructose-enriched inulin (5 g) over a 4 h period
during which the participants remained in the laboratory. A double blind placebo (maltodextrin)
controlled study (N = 47) was carried out with the order of conditions being counterbalanced and
the two sessions a week apart. On each test day mood and cognitive performance were assessed at
baseline (at 8:00) and then following inulin or placebo (at 11:00). Prior to the second test session (at
10:30) participants completed a questionnaire assessing their physical symptoms and mental health
during the test morning. The inulin and placebo were provided in powder form in 5 g sachets.
Volunteers consumed one sachet in decaffeinated tea or decaffeinated coffee with breakfast (9:00).
Questionnaire results showed that on the day that the inulin was consumed, participants felt
happier, had less indigestion and were less hungry than when they consumed the placebo. As
for performance and mood tasks, the most consistent effects were on the episodic memory tasks
where consumption of inulin was associated with greater accuracy on a recognition memory task,
and improved recall performance (immediate and delayed). Further research is required to identify
the mechanisms that underlie this effect with glucose metabolism being one candidate
Elbow joint variability for different hand positions of the round off in gymnastics.
Get PDFThe aim of the present study was to conduct within-gymnast analyses of biological movement variability in impact forces, elbow joint kinematics and kinetics of expert gymnasts in the execution of the round-off with different hand positions. Six international level female gymnasts performed 10 trials of the round-off from a hurdle step to a back-handspring using two hand potions: parallel and T-shape. Two force plates were used to determine ground reaction forces. Eight infrared cameras were employed to collect the kinematic data automatically. Within gymnast variability was calculated using biological coefficient of variation (BCV) discretely for ground reaction force, kinematic and kinetic measures. Variability of the continuous data was quantified using coefficient of multiple correlations (CMC). Group BCV and CMC were calculated and T-test with effect size statistics determined differences between the variability of the two techniques examined in this study. The major observation was a higher level of biological variability in the elbow joint abduction angle and adduction moment of force in the T-shaped hand position. This finding may lead to a reduced repetitive abduction stress and thus protect the elbow joint from overload. Knowledge of the differences in biological variability can inform clinicians and practitioners with effective skill selection
The effect of symmetrical and asymmetrical hearing impairment on the music quality perception
Get PDFThe purpose of this study was to investigate the effect of symmetrical, asymmetrical and unilateral hearing impairment on music quality perception. Six validated music pieces in the categories of classical music, folk music and pop music were used to assess music quality in terms of its ‘pleasantness’, ‘naturalness’, ‘fullness’, ‘roughness’ and ‘sharpness’. 58 participants with sensorineural hearing loss [20 with unilateral hearing loss (UHL), 20 with bilateral symmetrical hearing loss (BSHL) and 18 with bilateral asymmetrical hearing loss (BAHL)] and 29 normal hearing (NH) subjects participated in the present study. Hearing impaired (HI) participants had greater difficulty in overall music quality perception than NH participants. Participants with BSHL rated music pleasantness and naturalness to be higher than participants with BAHL. Moreover, the hearing thresholds of the better ears from BSHL and BAHL participants as well as the hearing thresholds of the worse ears from BSHL participants were negatively correlated to the pleasantness and naturalness perception. HI participants rated the familiar music pieces higher than unfamiliar music pieces in the three music categories. Music quality perception in participants with hearing impairment appeared to be affected by symmetry of hearing loss, degree of hearing loss and music familiarity when they were assessed using the music quality rating test (MQRT). This indicates that binaural symmetrical hearing is important to achieve a high level of music quality perception in HI listeners. This emphasizes the importance of provision of bilateral hearing assistive devices for people with asymmetrical hearing impairment
Innovative pedagogical practices in the craft of Computing
Get PDFComputer programming, the art of actually instructing a computer to do what one wants, is fundamentally a practical skill. How does one teach this practical skill in a university setting, to students who may not be initially motivated to acquire it, and who may have a variety of past experience, or none at all? Furthermore, how does one do it in a resource-efficient way to large classes? Students are largely motivated by assessment: what is the best way to assess this skill? How does this skill relate to more abstract concepts like “computational thinking”? In this piece NTFs from very different universities explain their solutions
Asymmetry analysis of the arm segments during forward handspring on floor
Get PDFAsymmetry in gymnastics underpins successful performance and may also have implications as an injury mechanism; therefore, understanding of this concept could be useful for coaches and clinicians. The aim of this study was to examine kinematic and external kinetic asymmetry of the arm segments during the contact phase of a fundamental skill, the forward handspring on floor. Using a repeated single subject design six female National elite gymnasts (age: 19 ± 1.5 years, mass: 58.64 ± 3.72 kg, height: 1.62 ± 0.41 m), each performed 15 forward handsprings, synchronised 3D kinematic and kinetic data were collected. Asymmetry between the lead and non-lead side arms was quantified during each trial. Significant kinetic asymmetry was observed for all gymnasts (p < 0.005) with the direction of the asymmetry being related to the lead leg. All gymnasts displayed kinetic asymmetry for ground reaction force. Kinematic asymmetry was present for more gymnasts at the shoulder than the distal joints. These findings provide useful information for coaching gymnastics skills, which may subjectively appear to be symmetrical. The observed asymmetry has both performance and injury implications
The use of polymer stabilised earth foundations for rammed earth construction
Get PDFThis paper presents a case study as part of a Professional Doctorate research project discussing an ecological approach to housing in South Africa, where polymer stabilised earth foundations have been used to support single story rammed earth walls, in a house in South Africa. Rammed earth was chosen as a construction method for its low embodied energy and thermal mass characteristics. The subsurface strata upon which the house was built comprised of clayey, gravely, sandy soils that have resulted as a result of decomposition of granitic rocks. In order to ensure solid founding conditions the foundations were excavated to a depth of one and a half metres before the excavated material was stabilised and backfilled. The material was stabilised to 600 mm below top of floor level with 2% Portland cement and above that with a 5% polymer bitumen mixture reinforced with horizontal steel reinforcing rods. This foundation avoids the use of reinforced concrete and as a result a significantly smaller carbon footprint, while fulfilling the functional requirements of supporting the building and preventing rising damp. The polymer has, as it major component is bitumen emulsion, provided a waterproof layer. Rammed earth walls of 500 mm thickness were constructed on the foundation up to 4.2 meters in height and initial observations suggest that the foundations are satisfactory with no settlement or cracking detected