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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The Perceptions, Attitudes and Practices of Registered Dietitians Regarding Functional Foods

Berhaupt, Amanda 22 March 2010 (has links)
The term “functional food” (FF) has a variety of definitions resulting in term ambiguity. It is unclear Registered Dietitians’ (RDs) understanding and practices about FF. A descriptive, cross-sectional study investigated RDs’ perceptions, attitudes and practices regarding FF. A national random sample (n=1800) of RDs was mailed a FF questionnaire, 385 (22%) responded. Given five definitions from food-nutrition authorities, the majority of RDs did not agree on a definition, although three-fourths (n=292, 75.8%) perceived fortified foods as FF. Registered Dietitians agreed FF could improve health (n=266, 69.1%), prevent disease (n=282, 73.2%) and treat clientele (n=246, 63.9%), however were neutral (41.6%) or disagreed (37.7%) FF were herbs, or equivalent to medicine (32.7%, 49.2% respectively). Most RDs (n=290, 75.9%) ate FF; fewer (n=231, 61.4%) professionally recommended them. Nearly all (n=353) indicated interest in learning about FF. Registered Dietitians revealed inconsistencies between their perceptions, attitudes and practices regarding FF. Professional education is needed to resolve discrepancies regarding FF.
12

Processing, structure and properties of Al-matrix composites

Begg, Henry S. January 2013 (has links)
Three classes of Al-matrix composite were manufactured to combine dissimilar metals and incorporate structural hierarchy, in an attempt to develop unusual combinations of mechanical properties. The first class combined a brittle, nano-quasicrystalline forming Al-3Fe-2Cr-2Ti phase with a ductile Al-4Cu phase into a layered structure using low pressure plasma spraying (LPPS). By using a substrate with multi-scale topological features, an ultra-thick (>2mm) deposit was successfully sprayed, which was subsequently consolidated by hot rolling to reduce residual porosity. The microstructure comprised a 'brick-wall' structure consisting of a convoluted arrangement of inter-leaved discreet droplet splats. Structure-property relationships were studied for four volume fractions of ductile additions and in-situ electron microscopy of beams subjected to 3-point bending suggested the ductile additions were providing additional toughening to the composite by a crack-bridging mechanism. The second class of composite investigated highly deformed microstructures of Al with 20vol% additions of either Sn or Ti. Nano-scale fibrous structures of the minority additions were achieved via an accumulative extrusion method, where extruded rod was abraded, degreased, bundled and re-extruded. This process was repeated to create refined microstructures while retaining a large material section. Fracture properties were studied in three point bending and crack growth monitored using Digital Image Correlation (DIC) to produce strain fields of the deforming beam surface. Modest changes were observed in mechanical properties with weak interfaces between poorly bonded extruded rods dominating fracture behaviour. Whiskers formed on polished surfaces of extruded Al-20vol%Sn and were monitored in real time by electron microscopy. Growth rates of up to 2.8nm/s were measured, which exceeds re- ported values in the literature on electroplated coatings by at least one order of magnitude. This may provide a convenient new means of studying whisker formation and calls into question current growth models. The third class of composite combined heavily rolled sheets of Al-20vol%Sn and Al-20vol%Ti with glass fibre/epoxy sheets to produce a laminate with multi-scale architecture. This laminate was designed as a proof-of-concept hierarchical material with structures ranging from the near millimetre scale of the metal-polymer layers, to the micro-sized glass fibre reinforcement of the epoxy and the nano-scale filamentary/lamellar microstructure of the highly deformed metal sheets. Fracture of such laminates was investigated in 3-point bending with continuous optical monitoring.
13

Hydrogen distribution and redistribution in the weld zone of constructional steels

Smith, Richard Dominic January 1999 (has links)
The invention of electric arc welding revolutionized the steel construction industry, but also brought some problems when the welded region has inferior properties compared to the plate metal. A major cause of brittle failure was identi ed as hydrogen embrittlement of the weld zone, although a comprehensive understanding of this phenomenon is not, even now, available. Hydrogen in solution in the weld zone is found in arc welds, due to the intense conditions in the welding arc. There is invariably a sufficient source in the form of moisture and hydrocarbon residue to give a few parts-per-million (ppm) by mass of hydrogen in the weld pool, which is a sufficient concentration to bring the possibility of hydrogen cold cracking in the completed weld. Hydrogen is significantly mobile in steels at room temperature, which is certainly why a few ppm of hydrogen can concentrate on a microscopic scale and initiate cracks, but also means that on a macroscopic scale there is hydrogen dispersion, which can relieve the cracking risk or place hydrogen in hydrogen cracking susceptible regions. The understanding of solubility and mobility of hydrogen in steels of different compositions and microstructures is therefore paramount. The question investigated in this work is whether the characteristics of the weld hydrogen cracking tendency can be explained by the features of weld hydrogen transport, especially when steel selection is a variable. Plate steel ranging from a 0.22%C pearlitic steel to a 0.05%C thermo-mechanically controlled-rolled and accelerated-cooled (TMCR-AC) high strength low alloy (HSLA) steel with no pearlite, plus a 0.4%C non-plate steel, were included in the experimental program. Welds were made with rutile ux-cored-wire (R-FCW) at two hydrogen levels, together with rutile shielded-metal-arc (R-SMA) welds. In order to investigate the di usion rates, a novel experiment has been devised. The welded plate has been milled away at an angle from the underside of the weld to provide increasing distances between the fusion boundary and the plate under-surface. The formation of hydrogen bubbles in glycerol enabled the measurements of the time dependent diffusion distances. The results clearly show a square root time correlation, as expected from the Fickian mechanism and enabled the calculation of diffusion coefficients for different steels. A nearly four fold difference was found between the steels, with the fastest hydrogen movement in the TMCR-AC steel. To reveal the initial distribution of hydrogen some samples were frozen immediately after welding and machined under liquid nitrogen. This test ruled-out any signi cant hydrogen dispersion during the deposition of the weld and during the cooling down period. The experimental data were interpreted using a new numerical computer model, based on random jumps of hydrogen between equivalent lattice sites. It is shown that this numerical model gives identical results to the analytical Fickian approach, but has the advantage that it can be used for any boundary shape. When this model has been applied to the experimental data, some unexpected features have been found. The amount of hydrogen emerging at surfaces distant to the weld was higher than expected from a concentration-driven mechanism; suggesting that a di erent transport mechanism should be applied. The numerical model has also indicated a discontinuity in the hydrogen concentration at the fusion boundary. It is a consequence of the model that hydrogen solubilities and di usivities are inversely related properties of the metal; a feature which is supported by experimental evidence. The tendency of hydrogen cracking to appear in the weld metal rather than in the heat-a ected-zone (HAZ) can thus be explained by higher di usivity of hydrogen in the plate metal. It appears that there is a relationship between the diffusivity and the microstructure, particularly when the content and form of carbon is considered.
14

The Misguided War on Processed Food: How and How Not to Reduce Obesity

Lindsey, Erica January 2018 (has links)
Thesis advisor: Joseph Quinn / The obesity epidemic is highly prevalent, growing and costly to the American public. The burden of obesity-related healthcare and productivity costs fall on employers, the government and the public at large, making it a cause of concern for all. Processed foods have received much of the blame for rising obesity rates in the United States, creating an "organic revolution." However, fast food giants still dominate the market. Changes such as mandated calorie labeling on menus and fat taxes have been attempted, but obesity rates are still growing. Policy action to successfully reduce and prevent obesity must target food environments, influence individual behavior, and support health services. / Thesis (BA) — Boston College, 2018. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Economics.
15

Investigating Associations between Consumption of Unprocessed and Ultra Processed Foods and Maternal and Neonatal Health Outcomes—Secondary Outcomes of LIFT Trial

Whyte, Kathryn Josephine January 2019 (has links)
The ultra-processing of food has become a much more important aspect of dietary patterns and dietary quality in terms of its impact on body weight, diet related diseases, health, and well-being in the past decades. NOVA is a set of guidelines developed that classifies diet quality by degree of food processing. The NOVA guidelines distinguish four categories: unprocessed /minimally processed foods; culinary ingredients; processed foods; and ultra-processed foods. Numerous studies have found an association of ultra-processed foods and health conditions such as obesity and metabolic syndrome. This study analyzed the associations between maternal diet quality as measured by NOVA and maternal anthropometric and neonatal body composition outcomes. The optimal method of nutrition intervention and education for this special population remains unknown; using NOVA may provide researchers with a different lens to assess diet quality and health care professionals with additional vocabulary to convey more tailored messages regarding optimal nutrition strategies for mother and offspring. Using data collected from a large randomized controlled intervention trial at pre and post intervention, this study aimed to compare the NOVA guidelines assessment of maternal diet quality to the parent study assessment of diet quality, the Healthy Eating Index (HEI), using statistical correlations. Secondly, this study aimed to look at the relationship of ultra-processed food intake to the maternal gestational weight gain experience using a logistic regression. Thirdly, this dissertation aimed to explore the relationship between maternal ultra-processed food intake and neonatal lean mass as measured by quantitative magnetic resonance (QMR) and fat free mass as measured by air displacement plethysmography (ADP: PEAPOD). In terms of maternal outcomes, the study found that NOVA and HEI were significantly correlated at pre intervention but not at post intervention. The odds of gaining excessive gestational weight decreased as maternal ultra-processed food intake increased - which was not in the hypothesized direction - when using study participant data. However, the odds of gaining excessive gestational weight increased as maternal ultra-processed food intake increased - which was in the hypothesized direction - when using the Institute of Medicine weight gain recommendations. Also, while obesity did not predict excessive gestational weight gain, those with obesity ultra-processed food intake did predict gestational weight gain. These various inconsistencies are likely due to the instability of the dietary intake data because only one 24 -hour dietary recall was obtained from mother. In addition, the mothers’ diets were very healthy to begin with, where ultra-processed food intake formed about 45% of calories both pre and post intervention, when the national average is 57%. Race was also significant predictors of gestational weight gain for the mothers. Being non-white significantly increased the odds of gaining excessively as did the interaction of having obesity and eating more ultra-processed foods. In terms of neonatal outcomes, findings from this study suggest that length and fat mass are significant predictors of lean mass in neonates. In terms of the impact of maternal ultra-processed food intake, the higher the consumption of ultra-processed food, the greater the neonatal lean mass, which this was not in the hypothesized direction. However, the association was minimal with very small beta weights and regression line, when plotted was quite flat, so that the finding is not clinically meaningful. It remains important to know whether maternal ultra-processed food intake influences gestational weight gain and the body composition of the neonate. Thus, future research should include using similar data analyses on a population with a more nationally representative diet, a larger sample size, and a more robust measure of dietary intake such as three 24-hour recalls. Given that a similar recent study found ultra-processed food to be highly predictive of maternal and neonatal outcomes, and many other studies have demonstrated that ultra-processed food is related to several health conditions in many countries that this study did not measure, it seems prudent for healthcare providers to take advantage of prenatal visits as a window of opportunity to encourage the consumption of unprocessed and minimally foods and help women make informed decisions regarding ultra-processed foods.
16

Identification of labelling errors and concerns on specific categories of South African processed food products that may impact consumer health

Van Dyk, Maritza January 2007 (has links)
Thesis (MTech (Consumer Science: Food and Nutrition))--Cape Peninsula University of Technology, 2007 / Labels are the source of information about the contents of food products and must be correct so that consumers are not misled and can make informed product choices. However, food label information is often incorrect, misleading or just insufficient. The aim of this study was to determine the labelling errors and concerns that occurred in specific categories of the South African processed food market. Randomly selected food product labels (N=246) were evaluated that represented the selected categories of processed foods (N=7), namely: breakfast cereal (9%), savoury snacks (13%), sweet snacks (29%), non-refrigerated meals (7%), refrigerated meals (9%), soups and sauces (25%) and convenience desserts and baked goods (8%). A pre-tested labelling checklist was used to evaluate each food label according to the food labelling areas that could impact consumer health considering the current South African labelling regulations published in 1993, the draft of these regulations published in 2002, and the further new proposed draft regulations. Labelling errors found induded the use of prohibited statements and not identifying compound ingredients (19% and 12% of the products respectively). A labelling concern was also the lack of identification of the fatsloils used (61% of the products). Further concerns identified included the lack of additive-free and allergen-free claims. For example, significant differences (p<O.05) were found between the number of products claiming to be aclditive-free and those that could have made such ctaims but did not. A real concern was the listing of ingredients of unknown origin with allergenicity potential (80% of the products). The breakfast cereal category contained the most eneigy and nutrient claims and nutritional education information, with most errors identified in the categories refrigerated meals and soups and sauces, and most concerns in the category savoury snacks. There is scope for food labelling improvement, specifically in the areas of ingredient and allergen identification, additive-free claims and heaJth-related information provision.
17

Mommy Is Not At Home! What Should We Eat Today,Daddy?¢w The Image of Father Represented in Instant Processed Food Advertisements

Chang, Pei-ying 24 June 2009 (has links)
Media is an important social institution to shape gender image especially TV advertising. People expose to a lot a great deal of TV advertising in their daily life. In recent years, the image of ¡§family man¡¨ has appeared on food advertising especially instant processed food advertising that attracts lots of attraction. Thus, this study aim to explore why the image of¡¨family man¡¨ such as ¡§father¡¨ appears on instant processed food advertising? How the image of father is represented on instant processed food advertising? And are there any domestic culture values or ideology hidden in the texts of instant processed food advertising? Semiotic theory is adopt as analyzing methodology in exploring mainstream discourse about father in Taiwan, through images, story and voice-over in advertising.By means of analyzing 12 advertising broadcast during 2005 to 2008, this research tries to understand the image of father represented on the instant processed food advertising. The major finding revealed that fathers are middle age, breadwinner and the sex role- model of son in advertising. The temperaments of fathers in advertising are multiple. Fathers in advertising could be an authoritative father or a new nurturant father. This study also found the relationship between father and other family members is patriarchy. The interaction between father and son is different from father and daughter. And the interesting thing is the study found that product in advertising only solves father¡¦s problems. The study also found fatherhood only be practiced in the text which mother is absent. By means of observing cooking, this study found there are differences between fatherhood and motherhood.In conclusion, even if the concept of ¡§a new nurturant father¡¨ is popular, we still can see a patriarchy society in these texts of instant processed food advertising.
18

Kombination analytischer Strategien und multivariater Datenanalysen zur Beurteilung von Milch- und Molkereierzeugnissen

Schwietzke, Uta 14 May 2012 (has links) (PDF)
Milch und daraus hergestellte Erzeugnisse spielen eine zentrale Rolle in der Ernährung des Menschen. Infolge einer Optimierung der molkereitechnologischen Produktionsprozesse ist eine gesteigerte Qualität sowie eine verlängerte Haltbarkeit dieser Produkte erzielt worden, wobei dies das Fundament des bis heute beständig wachsenden, vielfältigen Produktspektrums an Milch und der daraus hergestellten Erzeugnisse bildet. Die Globalisierung der Märkte sowie die in den letzten Jahren stark ansteigenden Rohstoff- und Energiekosten haben dabei zu einer erheblichen Verschärfung des Konkurrenzdrucks auch zwischen Lebensmittelproduzenten geführt. Um kostensenkend zu produzieren werden zahlreiche Massnahmen ergriffen, welche vorwiegend auf dem Ersatz von Fett- und Proteinanteilen, der Mischung von Milchsorten unterschiedlicher Spezies, dem Zusatz billiger Füllstoffe auf Milchbasis zur Ausbeuteerhöhung sowie einer falschen Deklaration von Produkten geschützter geografischer Herkunft beruhen (De la Fuente et al. 2005). Der Einfluss des globalisierten Milchmarktes macht dabei auch vor Schmelzkäseerzeugnissen und Schmelzkäsen keinen Halt. Produzenten dieser Produkte wurden infolgedessen mehr und mehr dazu verleitet, die in diesen Erzeugnissen wertgebende Rohware Käse anteilig durch günstigere Füllstoffe auf Milchbasis zu ersetzen. Neben ernährungs-physiologischen und technologischen Aspekten spielen in diesem Zusammenhang vor allem ökonomische Interessen eine entscheidende Rolle. Dem Endprodukt Schmelzkäse ist dieser Qualitätsverlust, welcher durch den Austausch von Käse-Protein durch Nicht-Käse-Protein resultiert, dabei auf den ersten Blick nicht unbedingt anzusehen. Bislang existieren auch keine einfachen analytischen Marker zur qualitativen Unterscheidung, geschweige denn quantitativen Bestimmung, dieser Rohwaren in Schmelzkäsen. Die analytischen Herausforderungen welche sich aus der vorliegenden Problemstellung ergeben, sind dabei sehr vielfältig. Nicht nur, dass alle wertgebenden Zutaten von Schmelzkäsen einem gemeinsamen Ausgangsrohstoff Milch entstammen, welcher zudem noch natürlichen Schwankungen in der Zusammensetzung unterliegt, sondern auch die in der wertgebenden Rohware Käse sorten-, reifungs- und lagerungsabhängig ablaufenden Prozesse führen zu starken Schwankungen der Zusammensetzung dieser Produkte. Wie genau die große Gruppe der Käsesorten basierend darauf chemisch charakterisiert werden kann, erscheint aus analytischer Sicht äußerst anspruchsvoll. Darüber hinaus kann eine Beeinflussung der chemischen Zusammensetzung der fertigen Schmelzkäseprodukte auch durch die während des Herstellungsprozesses herrschenden Bedingungen hervorgerufen werden. Das Ausmaß einer solchen Veränderung in handelsüblichen Schmelzkäsen ist jedoch nur schwer abschätzbar und bislang wenig erforscht worden. Einer Irreführung und Täuschung der Verbraucher sowie einer Verzerrung des Wettbewerbs zwischen den einzelnen Schmelzkäseproduzenten ist somit Tür und Tor geöffnet. Dies wird letztlich auch durch den Gesetzgeber nicht unterbunden, da dieser die Deklaration der eingesetzten Menge und Sorte an Käse sowie der Menge an zugesetztem Proteinzusatz zur Herstellung von Schmelzkäsen und Schmelzkäseerzeugnissen nicht zwingend fordert. Das Ziel der vorliegenden wissenschaftlichen Arbeit besteht somit darin, ein Analysenportfolio verschiedenster, analytischer Parameter zur Bestimmung der kompositionellen Zusammensetzung von Schmelzkäseerzeugnissen zu erarbeiten, mit deren Hilfe eine Unterscheidung der am Markt erhältlichen Produktqualitäten möglich ist. Weiterhin soll anhand der Kombination dieser analytischen Messgrößen sowie deren mathematischer Auswertung mittels multivariater Datenanalyseverfahren eine Bewertung und Priorisierung hinsichtlich deren Aussagekraft vorgenommen werden. Neben der Analyse handelsüblicher Schmelzkäse werden im Rahmen dieser Aufgabenstellung auch verstärkt die Schmelzrohwaren und Proteinzusätze sowie Modell-Schmelzkäse hinsichtlich deren chemischer Zusammensetzung charakterisiert. Das Hauptaugenmerk liegt dabei auf der Unterscheidung der Rohwaren Käse und den zum Schmelzkäseprodukt weiterhin zugesetzten Proteinpulvern auf Milchbasis. Zu diesen zählen neben den Trockenmilch- und Trockenmolkeerzeugnissen (Magermilchpulver, Milchpulverkonzentrat, Molkepulver) auch Milcheiweiß-erzeugnisse (Säure- und Labcasein). Zusammen stellen diese mengenmäßig den größten Anteil in Schmelzkäsen dar und bestimmen somit maßgeblich deren technologische und sensorische Eigenschaften und damit verbunden die Qualität und den Preis der fertigen Schmelzkäseprodukte.
19

Development of new instrumental techniques for measurement of stickiness of solid particulate food materials

Boonyai, P. Unknown Date (has links)
No description available.
20

The micro-foundations of dynamic capabilities, market transformation and firm performance.

Liao, Tung-Shan January 2010 (has links)
The emergence of the dynamic capabilities view has essentially extended the resource-based view, while also providing an integrated framework for an understanding of how firms evolve and how they secure competitive advantage in rapidly changing environments. While much research into dynamic capabilities has been developed in the theoretical and qualitative arenas, there has of yet been limited empirical support for its core assumptions. Such a limitation, authors have noted, may be due to its equivocal framework and the lack of a model with specified antecedents. This research conducts both conceptual and empirical works to address this gap. The primary goal of the research is to clarify the conceptual structure of dynamic capabilities, while also investigating potential micro-foundations of dynamic capabilities and their influences on firm performance. These micro-foundations, as the research traces back to the origins of dynamic capability from much firm capability and strategic management literature, could potentially include innovation, processual formalisation, social integration platforms (i.e. employee training and education) and the application of information technology. Alternatively, the research also looks into a possible extension of the dynamic capabilities view by extending inter-firm activities. In this part, the exploratory focus is on the relationship between a firm’s intended actions and its employment of alliance portfolios for capability and resource development. Using a subsample in the Australian manufacturing SME sector (from the Business Longitudinal Survey), the research finds a significant mediating effect of market transformation on the inter-relationships within the nexus of dynamic capabilities and firm performance. The empirical evidence of the research suggests that a firm’s dynamic capabilities are able to be viewed as a driver of competitive performance of firms insofar as they become evident in marketplaces. In other words, a firm’s development of dynamic capabilities confers upon the firm an adaptive capability in response to, or indeed perceiving, market dynamics, which in turn leads to superior performance. For the issue of inter-firm capability development, the research also finds that a firm’s capability development is indeed able to be achieved through some potential inter-firm specific activities. The empirical findings suggest that, for a purpose of capability development, alliance portfolios employed by a firm are able to be viewed as an approach to filling its resource stock or exploiting a perceived opportunity in its operational and strategic environments. In addition to the provision of empirical evidence, the research also extends the discussion of capability development by utilising a contextual case discussion in Taiwan’s ICT industry. Comparing strategy adoptions between OBM and OEM/ODM from Taiwan’s ICT businesses, the research reveals that many firms’ long-term and successful path dependencies that are absent the mediating arrangements discussed above may in fact form an obstacle to financial performance and growth into new business locales. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1522593 / Thesis (Ph.D.) -- University of Adelaide, Business School, 2010

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