Understanding flavour nutrient learning: the impact of extinction and expectation

Humans and other animals learn to associate flavours with aspects of consuming foods, which can result in acquired liking or aversion for that flavour. Two main processes of learning have been proposed to be critical: flavour-flavour (FFL) and flavour-nutrient (FNL) learning. This thesis addresses two main research questions primarily in the context of FNL; firstly, does liking for a flavour acquired through FNL persist once energy has been removed? It has been suggested that acquired flavour liking is resistant to extinction, but there are conflicting results within the human literature, which has concentrated on FFL. Studies One and Two explored this but failed to demonstrate acquired liking, although they tentatively suggested that extinction did not occur for acquired liking as pleasantness ratings remained stable after removal of energy. The second research question investigated whether liking acquired through FNL was modulated by expectations. Study Three manipulated viscosity of a yoghurt drink to determine if this impacted upon FNL, as thicker products have been shown to signal higher energy content. Expectations were influenced by viscosity, but with little impact upon pleasantness ratings and little evidence that FNL was enhanced. Studies Four and Five used labelling to influence expectations regarding a yoghurt-based breakfast. Study Four found that when no information was provided, liking changed as predicted from FNL. Contrary to prediction, when congruent information about energy content was provided, this acquired liking was not demonstrated, and ratings remained stable across sessions. Study Five did not replicate this finding, with pleasantness ratings in line with FNL literature. Addition of a hedonic label actually resulted in decreased pleasantness of the breakfast over time, suggesting a contrast effect with the flavour not delivering what was expected. Methodological limitations are recognised, with measurement of liking and contingency awareness discussed as potential explanations for weaker findings

Donald Trump v. The Electorate: A Twitter Feud for the Ages

This thesis began as an exploration into Donald Trump’s Twitter use in the final year of his presidency, starting with his first (and at the time, only) impeachment and ending with the November 2020 election. As an incumbent running for re-election, Donald Trump broke from precedent by opting out of the traditional messaging strategy of expanding his base and promoting unity and instead focused on energizing his existing supporters. Throughout his campaign and presidency, his Trumpian-style of rhetoric which perpetuated an “us versus them” mentality resulted in threats and real violence by his supporters. The role of social media has grown tremendously in the past decade, and has shifted political messaging as a result. While traditional media had a structure to fact-check stories, social media allows for the constant sharing of oversimplified ideas. With Trump’s massive Twitter following, he was able to engage in tweet-storms on any given subject, no matter how accurate the content of his messages were. Social media companies frequently rebuffed calls to increase the policing and accountability of Trump’s accounts. But in 2020, they were faced with a challenge: a sitting president actively challenged the integrity of a national election. Twitter decided to fact-check his tweets, which helped limit the spread of disinformation. However, these labels were not enough to overcome the circulation of lies that the election was stolen, bolstered by Trump and other Republicans across the country. By comparing the escalation of violence with the online messaging between November 2020 and January 2021, I conclude that Trump’s repeated claims that his supporters must “stop the steal” and fight for the country led directly to the kind of violence we witnessed on January 6th

The speaking vocabulary of kindergarten, grade I, grade II, and grade III

Thesis (Ed.M.)--Boston Universit

A Transiting Hot Jupiter Orbiting a Metal-Rich Star

We announce the discovery of Kepler-6b, a transiting hot Jupiter orbiting a star with unusually high metallicity, [Fe/H] = +0.34 +/- 0.04. The planet's mass is about 2/3 that of Jupiter, Mp = 0.67 Mj, and the radius is thirty percent larger than that of Jupiter, Rp = 1.32 Rj, resulting in a density of 0.35 g/cc, a fairly typical value for such a planet. The orbital period is P = 3.235 days. The host star is both more massive than the Sun, Mstar = 1.21 Msun, and larger than the Sun, Rstar = 1.39 Rsun.Comment: 12 pages, 2 figures, submitted to the Astrophysical Journal Letter

Great bowerbirds create theaters with forced perspective when seen by their audience

Birds in the infraorder Corvida [1] (ravens, jays, bowerbirds) are renowned for their cognitive abilities [2–4], which include advanced problem solving with spatial inference [4–8], tool use and complex constructions [7–10], and bowerbird cognitive ability is associated with mating success [11]. Great bowerbird males construct bowers with a long avenue from within which females view the male displaying over his bower court [10]. This predictable audience viewpoint is a prerequisite for forced (altered) visual perspective [12–14]. Males make courts with gray and white objects that increase in size with distance from the avenue entrance. This gradient creates forced visual perspective for the audience; court object visual angles subtended on the female viewer’s eye are more uniform than if the objects were placed at random. Forced perspective can yield false perception of size and distance [12, 15]. After experimental reversal of their size-distance gradient, males recovered their gradients within 3 days, and there was little difference from the original after 2 wks. Variation among males in their forced-perspective quality as seen by their female audience indicates that visual perspective is available for use in mate choice, perhaps as an indicator of cognitive ability. Regardless of function, the creation and maintenance of forced visual perspective is clearly important to great bowerbirds and suggests the possibility of a previously unknown dimension of bird cognition

Optimisation of octinyl succinic anhydride starch stablised w1/o/w2 emulsions for oral destablisation of encapsulated salt and enhanced saltiness

Sodium (salt) was encapsulated within the inner water phase of w1/o/w2 food emulsions externally stabilised by starch particles with the ultimate aim of enhancing saltiness perception. The physical properties of the starch particles were modified by octenyl succinic anhydride (OSA) treatment (0 - 3 %) to vary the degree of hydrophobicity of the emulsifying starch. During oral processing native salivary amylase hydrolysed the starch and destabilised the o/w emulsion releasing the inner w/o phase and subsequently sodium into the oral cavity, resulting in a salty taste. Whilst increasing OSA treatment levels increased the stability of the emulsion, intermediate or low levels of starch modification resulted in enhanced saltiness. It is therefore proposed that 1.5% OSA modified starch is optimal for sodium delivery and 2% OSA modified starch is optimal for sodium delivery in systems that require greater process stability. It is also shown that sodium release was further enhanced by oral processing and was positively correlated with native amylase activity. The results demonstrate a promising new approach for the reduction of salt or sugar in emulsion based foods

‘One door closes, a next door opens up somewhere’: The learning of one Olympic synchronised swimmer

Although training in sport is necessary to reach Olympic status, a conditioned body is not the only outcome. Athletes also learn how to be Olympians. This learning involves taking on certain ways of acting, thinking and valuing. Such learning has implications beyond competition, as athletes eventually retire from elite sport and devote their time to other activities. This paper examines processes of learning and transition using the case of Amelia, a former Olympic synchronised swimmer. Through two in-depth interviews, empirical material was generated which focused on the learning that took place during this athlete’s career and after, during her transition to paid employment. A cultural view of learning was used as the theoretical frame to understand the athlete’s experiences. Our reading suggests that the athlete learned in various ways to be productive. Some of these ways of being were useful after retirement; others were less compatible. In fact, Amelia used a two-year period after retirement to reconstruct herself. Key to her eventual successful transition was to distance herself from the sport and to critically reflect upon her sporting experiences. We thus recommend that those involved with high-performance athletes foster a more balanced perspective that acknowledges and promotes ways of being beyond athletic involvement

Evaluating the Quality of Research into a Single Prognostic Biomarker: A Systematic Review and Meta-analysis of 83 Studies of C-Reactive Protein in Stable Coronary Artery Disease

Background Systematic evaluations of the quality of research on a single prognostic biomarker are rare. We sought to evaluate the quality of prognostic research evidence for the association of C-reactive protein (CRP) with fatal and nonfatal events among patients with stable coronary disease. Methods and Findings We searched MEDLINE (1966 to 2009) and EMBASE (1980 to 2009) and selected prospective studies of patients with stable coronary disease, reporting a relative risk for the association of CRP with death and nonfatal cardiovascular events. We included 83 studies, reporting 61,684 patients and 6,485 outcome events. No study reported a prespecified statistical analysis protocol; only two studies reported the time elapsed (in months or years) between initial presentation of symptomatic coronary disease and inclusion in the study. Studies reported a median of seven items (of 17) from the REMARK reporting guidelines, with no evidence of change over time. The pooled relative risk for the top versus bottom third of CRP distribution was 1.97 (95% confidence interval [CI] 1.78–2.17), with substantial heterogeneity (I2 = 79.5). Only 13 studies adjusted for conventional risk factors (age, sex, smoking, obesity, diabetes, and low-density lipoprotein [LDL] cholesterol) and these had a relative risk of 1.65 (95% CI 1.39–1.96), I2 = 33.7. Studies reported ten different ways of comparing CRP values, with weaker relative risks for those based on continuous measures. Adjusting for publication bias (for which there was strong evidence, Egger's p<0.001) using a validated method reduced the relative risk to 1.19 (95% CI 1.13–1.25). Only two studies reported a measure of discrimination (c-statistic). In 20 studies the detection rate for subsequent events could be calculated and was 31% for a 10% false positive rate, and the calculated pooled c-statistic was 0.61 (0.57–0.66). Conclusion Multiple types of reporting bias, and publication bias, make the magnitude of any independent association between CRP and prognosis among patients with stable coronary disease sufficiently uncertain that no clinical practice recommendations can be made. Publication of prespecified statistical analytic protocols and prospective registration of studies, among other measures, might help improve the quality of prognostic biomarker research