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An Investigation of the Health Benefits of Honey as a Replacement For Sugar In the DietChepulis, Lynne Merran January 2008 (has links)
Sugar (primarily sucrose) has been a part of the daily diet for literally hundreds of years, but research is now suggesting that sugar intake can be detrimental to our health. In particular, excessive consumption of simple sugars with high glycemic index (GI) values have been shown to cause overeating and weight gain. As well, elevated postprandial hyperglycemia can result after consuming sugars and this has been linked to disease formation and progression, the development of advanced glycation endproducts, inflammation and increased mortality rates. Honey has been recognised as having a number of beneficial health properties, including slower uptake into the bloodstream, a pharmacological action of reducing blood glucose levels and a high level of bioavailable antioxidants, all of which may mean that honey could be less harmful to health than sucrose in the diet. This study was therefore designed to investigate the health benefits of honey in the diet as a replacement for sucrose, using small animal studies. As well, because of the interest in using honey as a replacement for sucrose in sweetened dairy foods, a small number of in vitro investigations were carried out to determine whether honey could retain its bioactive properties when combined with milk/dairy products. Using the in vitro studies, it was shown that the combination of milk with honey had no effect on either the antibacterial or antioxidant capabilities of honey. During the animal feeding studies a number of significant findings were observed. In the earlier work it was shown that honey had a significant effect on protein metabolism when fed for 14 days at a level of 600 g/kg diet (comprising 480 g sugars and 120 g water) compared with animals fed an equivalent amount of sucrose. In this study, honey-fed rats exhibited significantly lower weight gains (p less than 0.001), food intake (p less than 0.05) and nitrogen intakes (p less than 0.05) and significantly higher faecal nitrogen outputs (p less than 0.05) compared with sucrose-fed rats. Animals fed a diet consisting of 480 g/kg of mixed sugars as in honey generally exhibited protein metabolism parameters that were comparable to those of the sucrose-fed rats, suggesting that the effects of honey on protein metabolism were not due solely to its distinctive sugar composition. Furthermore, in another study that specifically investigated the effects of honey on weight regulation, honey (100 g/kg diet) resulted in significantly reduced weight gain after 6 weeks (p less than 0.01) compared with animals fed the same amount of sugars as sucrose, although food intake was not reduced in this study. Percentage weight gains were shown to be comparable between honey-fed rats and those fed a sugar-free diet, suggesting that differences in glycemic control may be partly responsible for the results seen. Fasting lipid profiles and blood glucose levels were also measured in this study, but no significant differences were observed between diet groups. During long-term (12 months) feeding weight gain was again significantly reduced in rats fed honey (p less than 0.05) and a sugar-free diet (p less than 0.01) compared with those fed sucrose, the weights of honey-fed rats and those fed the sugar-free diet being comparable at the end of the study. In addition, blood glucose levels were significantly lower (p less than 0.001), and HDL-cholesterol levels significantly higher (p less than 0.05) in animals fed honey compared with those fed sucrose after 52 weeks, but no differences in these parameters were observed between rats fed sucrose and a sugar-free diet. No other significant differences in lipid profiles were observed. Immunity measures were improved after feeding honey or sucrose for 52 weeks, animals in both of these diet groups having significantly higher levels of neutrophil phagocytosis compared with those fed the sugar-free diet (both p less than 0.0001). In addition, the percentage of leukocytes that were lymphocytes was significantly higher in honey-fed rats at the end of the study. Furthermore, levels of oxidative damage in aortic collagen were significantly reduced in rats fed honey or the sugar-free diet (both p less than 0.05) compared with those fed sucrose after 52 weeks. Full body DEXA scans were also undertaken in this 12-month study to assess body fat levels and bone mineral composition and density, although they revealed few statistically significant differences. Percentage body fat levels were shown to be nearly 10% lower in honey-fed rats compared with sucrose-fed animals at the end of the study (p less than 0.05), but no other significant differences between diet groups were observed. With one exception, no differences in bone mineral composition or bone mineral density were observed between the three diet groups after 52 weeks. This data agreed with the results generated from two earlier studies that showed that feeding honey short-term (for 6-8 weeks) to rats that were either calcium-deficient or fed a low calcium diet had no effect on bone calcium levels, bone mineral content, bone mineral density or bone breaking parameters. Lastly, long-term feeding of honey to rats had a number of statistically significant effects on anxiety and cognitive performance when assessed using animal maze tasks. Anxiety-like behaviour was significantly reduced in honey-fed rats overall compared with those fed sucrose (p = 0.056) or a sugar free diet (p less than 0.05). Spatial memory was also better in honey fed-rats throughout the 12 month study, these animals not displaying the same degree of age-related spatial memory loss seen in the other two diet groups. No significant differences in recognition memory or learning capability were observed between diet groups after 52 weeks. In conclusion, both short-term and long-term feeding of honey result in a number of health benefits compared with eating similar amounts of sucrose. These include less weight gain, improved immunity, reduced levels of oxidative damage and improved cognitive performance.. These effects of honey are likely to occur through a number of different processes, although the presence of high concentrations of antioxidants and other minor components in honey are likely to be important contributors. Honey may therefore help to improve human heath if it is used as an alternative to sucrose in foods and beverages, although feeding studies in humans are required to assess its efficacy. In addition, more animal studies are needed to assess which features of honey (e.g. fructose content, antioxidant content and bioactivities) are required to achieve optimal effects, and to determine what impact heating and food processing may have on the beneficial health effects of honey.
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The effects of eye gaze and emotional facial expression on the allocation of visual attentionCooper, Robbie Mathew January 2006 (has links)
This thesis examines the way in which meaningful facial signals (i.e., eye gaze and emotional facial expressions) influence the allocation of visual attention. These signals convey information about the likely imminent behaviour of the sender and are, in turn, potentially relevant to the behaviour of the viewer. It is already well established that different signals influence the allocation of attention in different ways that are consistent with their meaning. For example, direct gaze (i.e., gaze directed at the viewer) is considered both to draw attention to its location and hold attention when it arrives, whereas observing averted gaze is known to create corresponding shifts in the observer’s attention. However, the circumstances under which these effects occur are not yet understood fully. The first two sets of experiments in this thesis tested directly whether direct gaze is particularly difficult to ignore when the task is to ignore it, and whether averted gaze will shift attention when it is not relevant to the task. Results suggest that direct gaze is no more difficult to ignore than closed eyes, and the shifts in attention associated with viewing averted gaze are not evident when the gaze cues are task-irrelevant. This challenges the existing understanding of these effects. The remaining set of experiments investigated the role of gaze direction in the allocation of attention to emotional facial expressions. Without exception, previous work looking at this issue has measured the allocation of attention to such expressions when gaze is directed at the viewer. Results suggest that while the type of emotional expression (i.e., angry or happy) does influence the allocation of attention, the associated gaze direction does not, even when the participants are divided in terms of anxiety level (a variable known to influence the allocation of attention to emotional expressions). These findings are discussed in terms of how the social meaning of the stimulus can influence preattentive processing. This work also serves to highlight the need for general theories of visual attention to incorporate such data. Not to do so fundamentally risks misrepresenting the nature of attention as it operates out-with the laboratory setting.
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Exploring models of time processing : effects of training and modality, and the relationship with cognition in rhythmic motor tasksKarampela, Olympia January 2017 (has links)
Timing can be defined as the ability to perceive temporal sequences and regulate timed behaviors. As in other animals, our ability to make accurate time estimations is crucial in order to accomplish several activities. Organisms can process time over a wide range of durations ranging from microseconds to days. In the middle of these extremes is the hundreds of milliseconds to seconds range which is important for many everyday behaviors, such as walking, speaking and dancing. Yet, how this is managed remains poorly understood. Some central issues with regard time processing in this particular time range are whether timing is governed by one, or by several different mechanisms, possibly invoked by different effectors used to perform the timing task, as well as, if cognitive capacities are also involved in rhythmic motor timing. This thesis includes three studies. Study I investigated the effects of short- term practice on a motor timing task. Analyses of the timing variability indicated that a substantial amount of learning occurred in the first hour of practice and declined afterwards, exhibiting no trend for further decrease across the remaining 60 or 210 minutes. This effect was similar across effector, amount of feedback, and interval duration. Our results suggested that training effects influenced mainly motor precision and raised the question of whether motor timing training influenced also cognitive capacities. Study II investigated the relationship between motor timing and cognition. Specifically, participants had to train a sensorimotor synchronization task (SMS) over several days, and the question was whether this training would improve cognitive performance. A near transfer effect was found between the sensorimotor synchronization task and the sustained attention task, indicating that sustained attention is involved in motor timing. Study III compared the timing variability between the eyes and the hands, as a function of four different intervals, in order to examine whether these systems are temporally controlled by the same or different mechanism(s). The results showed several positive correlations in variability, between the eye and the finger movements, which, however, were significant only for the longer intervals. In addition, they were differences in variability between the eye and the hand, for the different interval durations. In general, the pattern of results from these studies suggested that voluntary motor timing is managed by overlapping distributed mechanisms and that these mechanisms are related to systems that manage cognitive processes, such as attention. The results partially explain the well-known relationships between cognitive ability and timing.
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搜尋結果之預期一致性與關聯性對關鍵字廣告效果之影響 / The Influence of Expected Consistency and Relevancy of Search Results on the Effects of Keyword Advertising郭怡吟, Kuo, I Yin Unknown Date (has links)
隨著消費者對網路使用習慣與依賴度提升,網路廣告目前在消費者端的發展日趨成熟,尤其是關鍵字廣告;因其更能精準的鎖定目標顧客,以及成本相對低廉,受到廣告主的青睞與重視,在廣告市場的規模明顯成長。近年來更有許多企業藉由搭便車(piggybacking)的關鍵字廣告方式,購買競爭對手、通路品牌或非企業本身的產品名稱等關鍵字詞組,作為自己的關鍵字廣告,增加企業廣告的曝光機會。
本研究以實驗法操弄消費者使用不同的搜尋策略,產生的搜尋結果與品牌預期一致性及類別關聯探討關鍵字廣告的效果,共計發放642份問卷經由多變量變異數分析等方法,得出研究結論如下:
1. 以產品名稱搜尋,消費者對知名品牌的廣告產品態度與廣告品牌態度明顯優於不知名品牌。
2. 以品牌名稱搜尋,消費者對與預期一致的品牌的廣告注意、正面廣告態度、廣告產品態度、廣告品牌態度皆明顯優於非預期的品牌。
3. 關鍵字廣告產品與消費者預期搜尋的產品關聯高時,則消費者對廣告注意與瞭解程度顯著高於產品類別關聯低之產品;同時,對關鍵字之正面廣告態度、產品及品牌態度皆優於產品關聯低的廣告。
4. 認知需求會增強消費者對廣告產品類別關聯高的關鍵字廣告的瞭解能力與提升對廣告產品的態度。
5. 認知需求對搜尋結果是否與預期一致或知名品牌之廣告效果的調節效果不顯著。 / As consumers are relying more and more on the internet, web advertising has become more mature on the consumers’ side, especially for keywords advertising. Advertisers have favored keywords advertising due to its ability to precisely target its customer and relatively low cost, which resulted in a significant growth in the advertising market. Recently, many companies started to use piggybacking as a keyword advertising method, buying keyword phrases of competitors, channel brands or product names to use as their own keyword advertisement, in order to increase the exposure of their corporate advertisement.
This study used an experimental method to manipulate consumers using different search strategies, and investigated the influence of brand expected consistency and category relevancy. A total of 642 questionaires were analyzed by using MANCOVA analysis, and resulted in the following conclusions:
1. Search by product name: Consumers’ attitude toward advertising product and advertising brand were significantly better for well-known brands compared to unknown brands.
2. Search by brand name: Consumers’ advertising notice, attitude towards positive advertising, advertising product and advertising brand attitudes were significantly better for the expected consistency brand compared to inconsistency brands.
3. Consumers’ advertising notice, understanding, attitude towards positive advertising, advertising product and advertising brand were significantly better for highly relevant product categories compared to low relevant product categories of consumers’ search.
4. Consumers’ need for cognition enhanced the ability for consumers to understand the keyword advertising and raised their attitude towards the advertised product.
5. Consumers’ need for cognition regarding search results on the brand expected consistency or brand familiarity towards advertising effect was not significant to become a moderator.
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