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Hasnain, Saher. "Food environments in Islamabad, Pakistan." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:10da5535-3e49-4a49-a3a9-908075ec886e.
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This dissertation examines how concerns about food system transformations affect how middle class consumers in Islamabad, Pakistan, perceive and approach food consumption in their everyday lives. The dissertation is situated in the context of risky food environments and food fears resulting from intensified, industrialised, and increasingly lengthened global food systems. Working within food geography and food environments paradigms, this dissertation explores how the transformation of food systems is associated with increasing anxiety about food security and safety for middle class urban consumers in Islamabad. Qualitative data gathered from semi-structured interviews and participant observation is used to illustrate the effects external influences, such as energy scarcity and violent events, have on everyday food environments. The dissertation examines the ways in which conceptualisations of 'good food', and trust relationships are negotiated in these dynamic food environments. The intensely geographical nature of these food environments and food systems, and the role of place-specific contexts on perceptions and adaptations related to food anxieties are emphasised. Situated in literatures on food anxiety and food consumption emerging from geography, food studies, and anthropology, this dissertation challenges dominant discourses on alternative and ethical consumption in a globalising food system. The results of this research not only contribute to literature on South Asia, but also contribute to consumption practices of a burgeoning middle class in developing countries.
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Dorsey, Mark A. "Slow Food, Slow Architecture: Regional Approaches in Urban Environments." Cincinnati, Ohio : University of Cincinnati, 2009. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1243310191.
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Thesis (Master of Architecture)--University of Cincinnati, 2009.Advisors: John Hancock (Committee Chair), Gerald Larson (Committee Co-Chair), Terry Boling (Advisor). Title from electronic thesis title page (viewed July 25, 2009). Includes abstract. Keywords: Slow food; regional; local; place. Includes bibliographical references.
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Forrest, James Lloyd. "Reducing Fast Food Employee Turnover with Appealing Working Environments." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/4217.
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While all business leaders face problems with voluntary employee turnover, fast food business leaders often face turnover rates at twice the national average. Using Weiss and Cropanzano's affective events theory, this exploratory multiple case study detailed the investigation into strategies that fast food business leaders use to establish an appealing working environment that reduces employee turnover. A purposeful sampling process identified 9 fast food business leaders from 3 different fast food organizations within the Omaha, Nebraska metro area who had successfully established a positive working environment that reduced employee turnover. Data collection included semistructured interviews and review of company documents. Using Yin's 5 step analytic approach, 3 themes (fairness, communication, and trust) emerged relative to fast food business leaders' strategies to establish an appealing working environment that reduces employee turnover. Fairness included fair interpersonal treatment, regulation, and wage setting. Communication included training, employee engagement, and corrective actions. Fast food business leaders used trust as a feedback mechanism for their fairness and communications strategies. Business leaders using strategies of fairness, communication, and trust to establish appealing working environments that reduce employee turnover could increase profitability and productivity within the fast food industry. The implication for positive social change is that more consistent employment and less work-related stress increases the potential for employees and their families to become more involved within their communities.
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Cetateanu, Andreea. "Exposure to food environments, diet and weight status in children." Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/53374/.
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There is a growing interest in understanding how the built food environment influences health behaviours. Whilst policy interest in the influence of food environments on diet and body weight is growing, the evidence base is limited, particularly for environments beyond the home neighbourhood. Research in children is of particular importance, as it is known that dietary behaviours and weight tend to track into adulthood. This thesis addresses the gap in knowledge surrounding the influence of exposure to the food environment on weight and diet in children. It also takes into consideration the interactions with socio-economic status. Existing research exploring the environmental influences on diet and weight in children is reviewed, and a conceptual framework of key determinants identified is presented. Three studies are presented which investigate associations between different measures of exposure to the food environment and diet and weight. A systematic review investigating the use of GPS in studies of the food environment is also conducted. Additionally, a novel method for assessing environmental exposure is presented. The results from this research suggest that unhealthy food environments measured at an area level are generally conducive to weight gain and poorer diet, while the opposite is true for healthier food environments. Furthermore, this thesis supports the hypothesis that diet, weight and access to food are patterned by social class, and that the food environment partially mediates the well-known association between socio-economic status and weight status. However, findings were equivocal when using measuring exposure to the food environment at an individual level. This suggests that correctly measuring the characteristics of the food environment is important in order to disentangle their effects on health outcomes, and calls for efforts to attempt to reduce the heterogeneity in measures of the food environment employed.
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Stensland, Alexsis. "Healthy food access and policy: a study of rural and urban food environments in Riley County, Kansas." Kansas State University, 2015. http://hdl.handle.net/2097/19124.
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Master of Regional and Community PlanningDepartment of Landscape Architecture/Regional and Community Planning
Hyung Jin Kim
Accessing healthy food can be a challenge for people living in both rural and urban environments. A broad range of factors influences one’s food security, including the accessibility and affordability of food retailers, travel time to shopping, availability of healthy foods, and food prices. The connections between planning and food systems have begun to emerge and be examined but planners face many barriers when tackling food system issues that range from turf problems, a lack of knowledge that any problem exists, to a lack of funds. The study purposes were to 1) identify areas with low access to healthy food sources; 2) discover barriers and perceptions of healthy food accessibility among community members; and 3) explore current planning policies and practices for increasing healthy food accessibility. The study area of this case is Riley County, Kansas, which has lower food accessibility especially to health foods in low income areas located in urban neighborhoods, even though rural areas are further away from a healthy food store. The research has the potential to inform the local food system framework and provide guidance for local policy makers and stakeholder groups. Surveys were collected from 150 households in order to identify challenges and barriers respondents face when obtaining healthy food. Food prices and low income were the largest barriers survey respondents faced when obtaining healthy food. Interviews conducted among 6 individuals from planning offices, market, and community stakeholder groups and both urban and rural issues were discussed. Currently, there is understanding of the importance of healthy food but little action that follows. There are opportunities for planners and policy makers to get involved with planning for the local food system. Partnerships must be established to share resources and technical skills among stakeholders in order to plan for healthy community food systems.
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Li, Yanxia. "Identifying opportunities for local food systems transformation: An exploratory study of residents' food environments and food literacy in a master-planned community." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/211294/1/Yanxia_Li_Thesis.pdf.
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By understanding the residents’ food environments and food literacy, this study identified potential opportunities for the transition to a local food system in a master-planned community. This thesis used a mixed-method approach to explore how residents described their existing food environments and to what extent their food literacy was evident. The findings provide implications for a local food system transformation that might have positive social, economic, environmental, and health effects on the community.
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Bashir, Amreen. "Exploring the biological basis for Salmonella persistence in food manufacturing environments." Thesis, Aston University, 2016. http://publications.aston.ac.uk/28847/.
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The persistence of Salmonella spp. in low moisture foods is a challenge for the food industry as despite control strategies already in place, notable outbreaks still occur. The aim of this study was to characterise isolates of Salmonella, known to be persistent in the food manufacturing environment, by comparing their microbiological characteristics with a panel of matched clinical and veterinary isolates. The gross morphology of the challenge panel was phenotypically characterised in terms of cellular size, shape and motility. In all the parameters measured, the factory isolates were indistinguishable from the human, clinical and veterinary strains. Further detailed metabolic profiling was undertaken using the biolog Microbial ID system. Multivariate analysis of the metabolic microarray revealed differences in metabolism of the factory isolate of S.Montevideo, based on its upregulated ability to utilise glucose and the sugar alcohol groups. The remainder of the serotype-matched isolates were metabolically indistinguishable. Temperature and humidity are known to influence bacterial survival and through environmental monitoring experimental parameters were defined. The results revealed Salmonella survival on stainless steel was affected by environmental temperatures that may be experienced in a food processing environment; with higher survival rates (D25=35.4) at temperatures at 25°C and lower humidity levels of 15% RH, however a rapid decline in cell count (D10=3.4) with lower temperatures of 10°C and higher humidity of 70% RH. Several resident factories strains survived in higher numbers on stainless steel (D25=29.69) compared to serotype matched clinical and veterinary isolates (D25=22.98). Factory isolates of Salmonella did not show an enhanced growth rate in comparison to serotype matched solates grown in Luria broth, Nutrient broth and M9 minimal media indicating that as an independent factor, growth was unlikely to be a major factor driving Salmonella persistence. Using a live / dead stain coupled with fluorescence microscopy revealed that when no longer culturable, isolates of S.Schwarzengrund entered into a viable nonculturable state. The biofilm forming capacity of the panel was characterised and revealed that all were able to form biofilms. None of the factory isolates showed an enhanced capability to form biofilms in comparison to serotype-matched isolates. In disinfection studies, planktonic cells were more susceptible to disinfectants than cells in biofilm and all the disinfectants tested were successful in reducing bacterial load. Contact time was one of the most important factors for reducing bacterial populations in a biofilm. The genomes of eight strains were sequenced. At the nucleotide and amino acid level the food factory isolates were similar to those of isolates from other environments; no major genomic rearrangements were observed, supporting the conclusions of the phenotypic and metabolic analysis. In conclusion, having investigated a variety of morphological, biochemical and genomic factors, it is unlikely that the persistence of Salmonella in the food manufacturing environment is attributable to a single phenotypic, metabolic or genomic factor. Whilst a combination of microbiological factors may be involved it is also possible that strain persistence in the factory environment is a consequence of failure to apply established hygiene management principles.
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Katrini, Eleni. "Addressing food, water, waste and energy yields in urban regenerative environments." Research Showcase @ CMU, 2012. http://repository.cmu.edu/theses/55.
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“At the same time that we must respond to climate change and rising energy costs, we must also adjust our housing stock to fit a changing demographic and find more frugal form of prosperity. Such a transformation will require deep change, not just in energy sources, technology, and conservation measures but also in urban design, culture and lifestyles. More than just deploying green technologies and adjusting our thermostats, it will involve rethinking the way we live and the underlying form of our communities.” (Calthorpe, 2011)
Our cities are built dependent on centralized systems of water and waste management, food and energy production. This practice has proven efficient for a while; nonetheless as our cities expand with immense speed and population increases, severe issues of food access, waste accumulation, floods, water contamination and increased energy demand reveal the obsolescence of those systems. The solution does not lie anymore only in conservation and precautionary measures but in a diverse way of thinking and redesigning existing infrastructures. Through this thesis, several systems of urban agriculture, decentralized water management and treatment, as well as energy production from waste were identified and studied through literature and actual case studies. The ultimate goal of the research was to create a toolkit for urban regenerative environments, which will be used to introduce those systems to designers. The key component of the toolkit is the quantitative link between the spatial demands of each system and its efficiency.
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Banús, Paradell Núria. "New solutions to control robotic environments: quality control in food packaging." Doctoral thesis, Universitat de Girona, 2021. http://hdl.handle.net/10803/673469.
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Machine vision systems and artificial intelligence techniques are two active research areas
in the context of Industry 4.0. Their combination allows the reproduction of human
procedures while improving the performance of the processes. However, to achieve the
desired full automation, there is a need for new applications able to cover as many
industrial scenarios and processes as possible. One of the areas that needs further research
and development is the quality control of food packaging, and more specifically
in the closure and sealing control of thermoforming packages. The shortcomings in this
area were detected by TAVIL who, in collaboration with GILAB, proposed an Industrial
Doctorate to investigate, develop and integrate in real scenarios new methods to
improve the packaging stage of the food industry by using machine vision systems and
artificial intelligence techniques. In the context of this Industrial Doctorate, two focuses
of research were defined that differ at the level at which the problem is studied. The
first focused on the quality control of food packages, and the second on the efficient
management of machine vision systems in industrial scenariosEls sistemes de visió per computador i les tècniques d’intel·ligència artificial són dues àrees de recerca actives en el context de la Indústria 4.0. La seva combinació permet la reproducció de procediments humans millorant al mateix temps el rendiment dels processos. Malgrat això, per aconseguir l’automatització completa desitjada, hi ha la necessitat de noves aplicacions capaces de cobrir el màxim d’escenaris i processos industrials possibles. Una de les àrees que necessita més investigació i desenvolupament és el control de qualitat dels envasos d’aliments, i més concretament, el control del tancament i del segellat d’envasos termoformats. Les necessitats en aquesta àrea van ser identificades per TAVIL que, amb col·laboració amb GILAB, van proposar un Doctorat Industrial per investigar, desenvolupar i integrar en escenaris reals nous mètodes per millorar l’etapa d’envasat de la indústria alimentària mitjançant sistemes de visió per computador i tècniques d’intel·ligència artificial. En el context d’aquest Doctorat Industrial, s’han seguit dues línies d’investigació que es diferencien en el nivell en el qual estudien el problema. La primera línia es basa en el control de qualitat d’envasos d’aliments, mentre que la segona es basa en el control eficient de sistemes de visió per computador en escenaris industrials
Programa de Doctorat en Tecnologia
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Green, Harold D. "Interorganizational cooperation in uncertain environments the case of food aid management /." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0000689.
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Lo, Ying-Chu. "Evolution of Penicillium fungi : Adaptation and Degeneration in Fermented Food Environments." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS127.
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La domestication est un modèle idéal pour étudier les processus évolutifs car elle implique des événements d'adaptation récents avec une sélection forte. Les champignons sont de bons organismes modèles pour étudier la domestication et plus généralement l’adaptation, grâce à leurs petits génomes et leur facilité de manipulation. Ils sont utilisés depuis longtemps pour la transformation alimentaire, par exemple P. camemberti et P. roqueforti pour la fabrication du fromage, et la levure Saccharomyces pour la fermentation du vin et de la bière. Chez ces champignons, des caractéristiques bénéfiques ont été acquises pour la transformation alimentaire, et les transferts horizontaux de gènes se sont révélés être un moyen essentiel d’adaptation rapide dans l’environnement alimentaire. Ici, j’ai étudié principalement l’adaptation de deux espèces de Penicillium relativement distantes phylogénétiquement - P. nalgiovense et P. salamii, toutes deux utilisées pour la maturation de la viande séchée. J’ai étudié si ces champignons ont été domestiqués, c’est-à-dire si les populations alimentaires se sont adaptées à l’environnement de la viande séchée, et s’il y a eu une différenciation génétique par rapport à d’autres populations; j’ai aussi recherché si des traces génomiques d’adaptation pouvaient être détectées. En analysant des génomes complets, j’ai trouvé peu de diversité génétique et de structure de population chez P. salamii et encore moins chez P. nalgiovense. Des expériences ont montré que les populations de P. salamii et P. nalgiovense provenant de viande séchée présentaient des taux de protéolyse et de lipolyse plus faibles et des couleurs différentes de celles des populations de viande non séchée. De plus, nous avons trouvé des transferts de gènes horizontaux partagés par P. salamii et P. nalgiovense et absents chez d’autres espèces de Penicillium. En résumé, ces résultats indiquent une évolution convergente et une adaptation des populations de P. salamii et P. nalgiovense à la viande séchée. J'ai également étudié les conséquences de la domestication chez le champignon utilisé pour la production de fromages bleus, P. roqueforti, montrant une faible fertilité des souches fromagères par rapport aux souches non fromagères. Les résultats de la thèse soulignent donc l'importance des transferts de gènes horizontaux pour une adaptation rapide chez les champignons et renforcent l'idée que les champignons domestiqués pour la production de nourriture sont de bons modèles pour étudier l'adaptation et l'évolutionDomestication is an ideal model to study evolutionary processes due to the recent adaptation events and strong selection it implies. Fungi in particular are good model organisms to study domestication and more generally adaptation, with their small genomes and experimental tractability. Fungi have been used for food production, e.g., P. camemberti and P. roqueforti for cheesemaking, and Saccharomyces yeast for wine and beer fermentation. In these fungi, beneficial traits have been acquired for food production, and horizontal gene transfers (HGTs) have been shown to be a major way to rapid adaptation in food environment. Here, I mainly studied the adaptation of food Penicillium fungi using two distantly related Penicillium species - P. nalgiovense and P. salamii, both used for dry-cured meat maturation, to assess whether these fungi have been domesticated, i.e., whether food populations adapted to the dry-cured meat environment, whether were genetically differentiated from other populations, and whether we could find genomic footprints of adaptive events. Using genome sequencing, we found little diversity and population structure in P. salamii and even less in P. nalgiovense. Experiments showed that both P. salamii and P. nalgiovense dry-cured meat populations had lower proteolysis and lipolysis rates and different colors from non-dry-cured meat populations. Furthermore, we found HGTs shared by P. salamii and P. nalgiovense while lacking in other Penicillium species. Altogether, these results indicate convergence evolution and adaptation in P. salamii and P. nalgiovense dry-cured meat populations, as was previously found in cheese Penicillium fungi. I also studied the consequences of domestication in the blue cheese fungus P. roqueforti, showing lower fertility of cheese strains compared to non-cheese strains. The results of the thesis thus point out the importance of HGTs for rapid adaptation in fungi and reinforce the view that fungi are ideal models to study adaptation and evolution
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Cassar, Erin. "Food for Thought: Understanding the Role of Food and Food Policy in Low-Income Schools." Diss., Temple University Libraries, 2017. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/456118.
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Urban EducationPh.D.
This dissertation investigated the role of school food and food policy in three low-income, urban, predominantly African-American schools. Using critical policy analysis, this study examined two different school food programs, both of which complied with the National School Lunch Program nutritional guidelines. It employed ethnographic case study methods, including observations and interviews with a total of 59 participants over the course of two years. Findings indicated that feeling hungry interfered with students’ ability to pay attention during class, and students still felt hungry after eating prepackaged school breakfasts and lunches. On the other hand, students reported feeling more full, satisfied, and ready to learn after eating freshly-prepared foods. Additionally, participants described improved engagement within classrooms, as well as a more positive climate in the lunchroom with the fresh meals. While the tone was usually punitive and disciplinary during the prepackaged mealtimes, during the fresh meals served family-style, with students and faculty eating together, the tone was celebratory and communal. These findings indicate school food is an important, yet under-researched, aspect of schooling, with many fruitful avenues for future research and practice.
Temple University--Theses
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Campbell, Karen Jane, and karen campbell@deakin edu au. "Family food environments as determinants of children's eating: Implications for obesity prevention." Deakin University. School of Exercise and Nutrition Sciences, 2004. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20061207.120915.
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The prevalence of childhood obesity is escalating rapidly and it considered to be a major public health problem. Diet is a recognised precursor of fatness, and current evidence supports the premise that in Westernised countries, the dietary intakes of children are likely to be important in obesity genesis. However, we have a relatively poor understanding of the environments in which a childs eating is learnt and maintained. Much of the existing work in this area is based on small-scale or experimental studies, or has been derived from homogeneous populations within the USA. Despite these limitations, there is evidence that aspects of the childs family environment are likely to be important in determining obesity risk in children.
This thesis examines the impact of the family food environment on a childs eating through two related studies. The first study, titled the Children and Family Eating (CAFÉ) study comprised three phases. Phase one involved qualitative interviews with 17 parents of 5-6 year-old children to explore parental perceptions regarding those factors in a childs environment believed to influence the development of their childs eating habits. These interviews were used to inform the development of quantitative measures of the family food environment. The second phase involved the development of a Food Frequency Questionnaire (FFQ) to assess dietary intake in 5-6 year-olds. The FFQ was informed by analysis of 1995 Australian National Nutrition Survey data. In the final phase the relationships between dietary intakes of 5-6 year-old children, and potential predictors of dietary intake were examined in a cross-sectional study of 560 families. Predictors included measures of: parental perceptions of the adequacy of their childs diet; food availability and accessibility; child-feeding; the opportunities for parental modelling of food intake; a childs television exposure; maternal Body Mass Index; and maternal education. Analysis of the CAFÉ data provides unique information regarding the relationships between a childs family food environment and their food consumption. Models developed for a range of dietary outcomes considered to be predictive of increased risk for obesity, including total energy and fat intakes, vegetable variety, vegetable consumption, and high-energy (non-dairy) fluid consumption, explained between 11 and 20 percent of the variance in dietary intake. Two aspects of the family food environment, parental perception of a childs dietary adequacy, and the total minutes of television viewed per day, were frequently found to be predictive of dietary outcomes likely to promote fatness in these children.
The second study, titled the Parent Education and Support (PEAS) Feeding Intervention Study, was a prospective pre/post non-randomised intervention trial that assessed the impact of a feeding intervention to 240 first-time mothers of one-year-old children. This intervention focused on one aspect of the family food environment, child-feeding, which has been proposed as influential in the development of obesogenic eating behaviours. In this study, Maternal and Child Health Nurses (MCHNs), using a Division of Responsibility model of feeding, taught parents to provide nutritious food at regular intervals and to let children decide if to eat and how much to eat. Thus parents were encourages to food their child without exerting pressure, or employing coercion or rewards (controlling behaviours). The aim was to influence parental attitudes and beliefs regarding child-feeding. Through the use of these feeding techniques, this intervention also aimed to increase the variety of fruits and vegetables a child consumed by teaching parents to persist with offering these foods, over the year of the intervention, in non-emotive environments. Fruits and vegetables were chosen in this intervention because they are likely to be protective in the development of obesity. Analysis of the PEAS data suggests that this low-level feeding intervention, delivered through existing Maternal and Child Health services, was modestly effective in changing parental attitudes and beliefs regarding the feeding of young children. Further, the validity of fruits offered to intervention group children increased.
This thesis expands the existing knowledge base by providing a comprehensive analysis of the relative impact of aspects of the family environment on dietary intakes of 5-6 year-olds. Further, the analysis of a feeding intervention in first-time parents provides important insights regarding the potential to influence child-feeding and the impact this may have on the promotion of eating behaviours protective against obesity.
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Verschut, Thomas Alexander. "Searching for food in complex environments : Integrating processes at multiple spatial scales." Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-141762.
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Resources are often unevenly distributed through the environment, resulting in a challenging task for insects to locate food, mates and oviposition sites. Consequently, there is an ongoing need to unravel how insects rely on behavioural and sensory traits while searching for resources in heterogeneous environments. In the first part of this thesis, I addressed this issue by studying how neighbouring resources can affect the likelihood of insects finding their preferred host resources. These effects of neighbouring resources are commonly referred to as associational effects, and are expected to result from limitations in the sensory physiology of insects. Such limitations constrain the insect’s ability to correctly evaluate resource quality at the different steps involved in insect search behaviour. Furthermore, I determined whether the physiological state of an insect, and sensory experiences made during larval stages, can affect host search behaviour in heterogeneous environments. By comparing the behaviour of Drosophila melanogaster in environments with single and multiple resources, I found that the presence of neighbouring recourses increased the selection rates for attractive resources, while it decreased the selection rates for less attractive resources. These effects are referred to as associational susceptibility and associational resistance respectively. Furthermore, by studying oviposition behaviour, I found that during these small-scale behavioural decisions, associational effects are mainly governed by gustatory mediated selection and less by olfactory mediated selection. The oviposition assay eliminated potential misinterpretations of resource quality along the different steps of search behaviour, hence the results suggested that associational effects rely on distinctive selection behaviour between resource types rather than on sensory constraints. In the second part of this thesis I determined whether natal experiences can be used by insects as sensory shortcuts to find host resources, and whether this leads to better larval performance on those selected host resources. For this purpose, I studied the interactions between the larval parasitoid Asecodes lucens and the oligophagous leaf beetle Galerucella sagittariae. The results showed that the relationship between oviposition preference and larval performance, of both insect species, depends on an interactive effect between the insects’ natal origin and the quality of the different host resources. Moreover, I found that the natal origin was a better predictor for the adult host preference, rather than for larval performance. This suggests that, aside from the actual quality of the host resources, locating any suitable host might be even more limiting for the female’s fitness.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Accepted. Paper 3: Submitted.
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Bradshaw, Sandra. "Food Environments: What is the Role of Demographics in Figians' Decision Making Related to Food Choice and Overall Nutrition Behavior." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1960.
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Due to the recent increased quantity of nutrition-related diseases worldwide, current research recommends exploring environmental factors that influence this trend. The Islands of Fiji are of particular concern because of the growing number of non- communicable diseases. On the same small island, nutrition problems vary according to demographic. Thus, the different environments of each demographic constitute diverse food environments, which are manifested in varied nutrition concerns. This study explored environmental motivators of food choice for the Fijian population. Gathering the perspectives of Fijian Islanders using a narrative inquiry research format proved to be insightful in measuring the environmental influences of decisions pertaining to food.
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Saulnier, Matthew James. "LINKING THE HOME AND NEIGHBORHOOD FOOD ENVIRONMENTS REGARDING DIETARY INTAKE AMONG RURAL ADOLESCENTS." UKnowledge, 2015. http://uknowledge.uky.edu/foodsci_etds/35.
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Home availability of both healthful and unhealthful foods may influence consumption among rural adolescent populations. In conjunction, the availability of food in an individual’s local food environment has the potential to significantly impact what is procured for the home and eaten away from the home. The purpose of this study was to determine how in-store food availability and parental purchases influences home availability and, ultimately, dietary intake among adolescents. This study measured perceived home availability, using the University of Minnesota Project EAT Survey, and dietary intake, using the NHANES Dietary Screener Questionnaire, of (n=28) adolescent participants in two Kentucky counties during 2013. Availability of food in local stores was measured using the Nutrition Environment Measures Survey in Stores (NEM-S). The results of multiple linear regression analysis suggest that overall store availability does not significantly impact parental purchases. However, in-store availability of specific unhealthy food categories, such as snacks, junk food, candy, and pop, was associated with increased parental purchases of similar unwholesome items and a greater predicted intake of sugar. Therefore, it may be beneficial to develop interventions aimed at decreasing the availability of unhealthy food items in stores in order to improve diet quality among rural adolescents.
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Waters, Clarice Nhat-Hien. "Exploring the Food and Physical Activity Environments and Their Influence on Healthy Behaviors." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/24198.
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Using a community-based participatory research (CBPR) approach, community members, community stakeholders, and academic researchers from Virginia Tech formed a community-academic partnership in 2009. In the formative months, the coalition decided to focus on reducing obesity in the region. The coalition adopted the name of The Dan River Partnership for a Healthy Community (DRPHC) with a mission to "foster community partnerships to combat obesity in the Dan River Region through healthy lifestyle initiative". During a planning workshop, the DRPHC created six causal models for the root causes of obesity in the region. Two causal models that focused on geographic and environmental influences for obesity are the foundation for this series of research.
The focus of this dissertation is at the intersection of the food and physical activity environments and their characteristics that contribute to meeting fruit and vegetable intake and minutes of physical activity recommendations. The food environment is one aspect of built environment research that examines food locations for procurement and the variety, availability, and quality of different food options. To date, the vast majority of research on the food environment is based in urban, suburban, and metropolitan areas with high residential densities and populations. Rural areas are often understudied because of their dispersed and hard-to-reach populations; yet these individuals experience some of the worst health outcomes in the nation. This is due, in part, to the large overlaps of rural regions and food deserts, resulting in poor food choices and poor diets. The overall objective of this dissertation is to examine the associations of the food and physical activity environments with individual healthy behaviors.
Three studies were conducted within the broader research plan to meet the overall objective. The first study systematically examined the food environment using the Nutrition Environment Measures Survey (NEMS) for all food outlets in Danville, VA, a small regional city within the health disparate region, to compare differences in healthy available food options by block group race and income. The second study expanded NEMS methodology to encompass all food outlets in the three-county Dan River region to examine if food environment and availability of healthy options was predictive of meeting fruit and vegetable intake recommendations. The last study examined the objective and perceived distance individuals must travel to reach a physical activity outlet and whether or not distance was a predictive factor of individual weekly minutes of moderate to vigorous physical activity and meeting physical activity recommendations.Ph. D.
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Kypengren, Frida. "Adaptability in NGO-projects : Learnings from NGO-projects managing food security in unstable environments." Thesis, Uppsala universitet, Statsvetenskapliga institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-339566.
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The shift to a human security perspective has put food security on the agenda in development cooperation. In this world private actors are increasing their presence and a larger amount of aid is channeled through these organizations. However, there are little studies made on private actors in development cooperation, especially NGOs. The purpose of this study is therefore to deal with the theoretical uncertainty of NGO assistance and develop existing theory in order to confirm or dismiss previous assumptions. Previous research stress that NGO-projects are adaptable i.e. ability to change and adjust to manage sudden challenges, such as conflict. To what extent are NGO-projects to be classified as having adaptable project structures, and how is that manifested in aid within the area of food security? An ideal type was set up to measure adaptability involving three indicators: flexible, responsive, and inclusive. The empirical material was collected through interviews with project staff and project reports. The projects showed higher levels of adaptability than expected, also when controlling for two other cases. An adaptable project is recognized by its decentralized decision-structure, flexible budget, quick response, and access to remote areas.
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Pineda, Ana Elisa. "Examining relationships between food environments and adult obesity in Mexico using geographical information systems." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10061465/.
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Mexico has one of the highest rates of obesity and overweight worldwide: 73% of the population is overweight or obese. The country has experienced a dietary and food retail transition involving increased high-calorie-dense food and beverage availability: 163 L of sugar-sweetened beverages (SSB) were consumed on average per person in 2012. The obesity epidemic in Mexico increased significantly which suggests that the contributing risk factors are likely to be influenced by the environment. Therefore, this study aimed to assess the relationship between the food environment and obesity in Mexico. Food outlet geolocation was obtained from the National Institute of Statistics and Geography in Mexico; anthropometric measurements and socio-economic characteristics of adult participants came from the National Survey on Health and Nutrition in Mexico (ENSANUT) 2012. I calculated the density of supermarkets, restaurants, fast-food outlets, chain convenience stores (CCS) and non-chain convenience stores (NCCS), and fruit and vegetable stores separately and overall. The retail food environment index (RFEI), and the density of 'unhealthy' and 'healthy' food outlets were also calculated per CTA using ArcGIS. I then analysed the relationship between food outlet density types and obesity through five models which controlled for different covariates including gender, age, socioeconomic status and physical activity, using multilevel linear regression in STATA 14. Results indicated that density of NCCS [β=3.10, 95% CI: 0.97-5.23, p=0.004] and CCS [β=19.11, 95% CI: 1.59-36.63, p=0.003] and the RFEI [β=0.015, 95%CI: 0.049-0.0001, p < 0.05] were significantly directly associated with obesity whilst total, healthy and unhealthy food outlet density showed no significant associations. This study showed strong associations between both high densities of convenience stores and a higher proportion of unhealthy food outlets with higher levels of BMI in Mexican adults living in urban areas. Policy makers in Mexico should consider interventions aimed at tackling the obesogenic food environment in the country.
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Fallahi, Marvast Sara. "Evaluation of Norovirus Persistence on Farm and Agriculturally-relevant Environments." Thesis, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/20727.
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Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.
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Witarsa, Shirley Y. "Comparative Stability of Phytonutrients in Functional Beverages Stored under Different Environments." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313435529.
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Sherman, Corinna. "Redesigning Our Personal Environments and Behaviors: A Systems Approach to Wellness." Research Showcase @ CMU, 2011. http://repository.cmu.edu/theses/18.
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Health behaviors are triggered and reinforced by a system of environmental cues that only dimly impact conscious awareness. When people try to change their eating habits, they often struggle to break out of the self-defeating scripts that keep them entrenched in undesirable behavioral patterns and fail to take into account the environmental cues that undermine their efforts. By redesigning their personal environments, people can facilitate their own behavior change to promote wellness.
This thesis explores the ways in which individuals can redesign their everyday personal environments, from kitchens to desks to cars, to disrupt unhealthy patterns and create positive cues to support their desired behavioral transformation. Research conducted through literature review, surveys, interviews, journals, and generative modeling reveals needs for personalized wellness education, design inspiration, guidance that promotes self-efficacy, and long-term support for prioritizing and managing environmental and behavioral redesign.
A proposed web-based tool called Seeds of Health provides an adaptive framework for personal wellness transformation in an iterative, four-phase process: (1) exploration and assessment, (2) planning and preparation, (3) practice and tracking, and (4) reflection and adjustment. The tool is intended to serve as a personal wellness guide, planning tool, and evolving record of an individual’s behavioral and environment changes.
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Lekkas, Panagiotis. "The Microbial Ecology Of Listeria Monocytogenes As Impacted By Three Environments: A Cheese Microbial Community; A Farm Environment; And A Soil Microbial Community." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/463.
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This dissertation examined the microbial ecology of Listeria monocytogenes in three distinctly different environments: a cheese microbial community; a farm environment; and a soil microbial community.
The aim of the first study was to investigate the effects of L. monocytogenes on the composition of the surface microflora on washed rind soft cheese. Two trials with washed rind cheeses that were inoculated with 100cfu cm⁻² of a L. monocytogenes six strain cocktail were conducted. The first trial had to be terminated early (day 28) as contamination of Pseudomonas spp. from the initial brine did not produce the expected characteristics of the cheese during the aging period. For the second trial, cheese samples were aged in the lab for 60 days according to the cheesemakers specifications. Surface cheese rind samples were collected from both control and inoculated cheeses every 7 days. Cheese rind samples were analyzed through the standard BAM method for enumeration of L. monocytogenes and through amplification of the V4 region of 16S rRNA and ITS regions for identification of the surface rind bacterial and fungal communities, respectively. Our data showed that Pseudomonas spp. significantly changed the composition of the microorganisms found on the surface of the rind while L. monocytogenes had little effect. In addition, although the concentration of L. monocytogenes increased to levels of 10⁶ cfu cm⁻² based on the enumeration data, the genetic data was not able to identify it in the flora due to the fact that other genera were found at much higher concentrations, which is a limitation of molecular methods used for identification of pathogens in foods.
For the second study the presence and incidence of L. monocytogenes on farms that either produce raw milk cheese or supply the milk for raw milk cheese production was investigated. Five farms were visited and in total 266 samples were collected from barn, environmental, and milk sites. L. monocytogenes prevalence was found to be at 6% from all the farms tested with 10 isolates found in the barn samples, 5 from environmental sites and 1 from milking equipment. Samples were identified to the genus level through a modified BAM method and speciated though multiplex PCR. Included in the pathogenic isolates was a DUP-1042B L. monocytogenes strain that has been implicated in major outbreaks, which emphasizes the adaptability and persistence of highly pathogenic stains in food manufacturing environments. Results from this study continue to support the fact that contaminated silage can be an important reservoir of the pathogen in a dairy farm setting. From our data and field observations we identified that drinking water sources for the animals is also an important reservoir of L. monocytogenes in farm environments. More importantly this study has shown the importance of continuous monitoring of environmental sites for the presence of the pathogen, particularly in silage.
Lastly manure amended soils in the northeastern U.S. were tested for the presence and survival of rifampicin resistant Escherichia coli (rE. coli), generic E. coli (gE. coli) and Listeria spp.. Both gE.coli and rE.coli samples were processed using either direct enumeration, MPN or bag enrichment methods. Samples were taken from both tilled and surface dairy solid manure-amended plots. Listeria samples were processed using a modified BAM method. Listeria presence was constant throughout the study. In contrast, rE. coli and gE. coli levels declined with time. The main conclusions of this study were that soil type, location and physical characteristics have a significant role in the survival of bacterial populations of rE. coli, gE. coli and Listeria spp. in soil. Dairy solids application does not seem to have a long term effect on the natural microbial population of soils. Tilling of soils results in increased survival of the bacterial population due to the fact that it increases soil pore size and facilitates moisture entry, which in turn has been shown to increase bacterial survival rates. Data from this research will assist in the creation of preventative measures that lead to the elimination of pathogen reservoirs. It will be further used to verify that a 120 day interval following manure application should be sufficient to ensure food safety of edible crops subsequently planted on these soils.
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Fischer, Lukas. "Development of virtual environments to investigate path integration in mice." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/17999.
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Path integration is the ability to navigate to a goal location without using external cues, thus relying entirely on self-motion information. To do so, two components of a path need to be encoded: orientation and distance. While the ability to estimate distance, called linear path integration, is well established in humans, it is unclear whether rodents are equally capable of doing so and the underlying neural circuit mechanisms are only poorly understood. This thesis discusses the development of a virtual reality system and behavioural task to investigate linear path integration in mice, and the results obtained from experiments carried out with this system. The setup provides full control over visual input while de-correlating vestibular and olfactory signals from location. Manipulations of the translation from physical to virtual movement can thus be used to probe relative influences of motor related and visual signals. Chapter 1 reviews the current literature on path integration and provides a background to the technical setup of the system. Chapter 2 describes the design and construction of the virtual reality system, its individual components and the software created to run experiments. It discusses how 3-d modelling and 3-d printing have successfully been combined to allow rapid development and production of custom components in different materials. Chapter 3 discusses the development of behavioural tasks designed to investigate linear path integration. It shows that by using a simple virtual track design and a carefully monitored food-deprivation regime, mice can be trained to successfully associate a visually indicated location with a reward. Chapter 4 describes behavioural experiments carried out using this virtual linear track. I obtained evidence that mice can estimate the distance to the rewarded zone reliably using path integration strategies. To test whether mice rely on motor information or optic flow, I manipulated the gain between physical movement and virtual movement. My results suggest that mice primarily rely on motor information for linear path integration. In the final chapter the results are discussed in the context of other recent work and areas for further development of the system are identified.
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Holsinger, Amanda Joy Toscano. "Are Nutrition and Food Security Concerns a Priority of Certified Nursing Assistants in Work and Family Environments?" Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/31932.
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Certified Nursing Assistants (CNAs) are responsible for the care of Americaâ s aging population. CNAs are paid a miniscule amount of money and are often ineligible for medical benefits through their employers. CNAs bathe, change, feed, and help toilet the residents of long-term care facilities. The stressful work and personal lives of CNAs leads to many problems such as high turnover rates, absenteeism, health problems, and elder abuse. In the United States, food insecurity is a concern for many of the uninsured working poor. The purpose of this study was to assess the overall perceived concerns, barriers, and solutions of CNAs in both their work and family environments, identify where nutrition and food security fits into the priorities of CNAs, and identify educational strategies to improve their health and overall quality of life. Twenty-nine CNAs participated in six focus groups across the state of Virginia. Triangulation techniques were used to compare both qualitative (focus groups) and quantitative (participatory activities and questionnaires) research. Participatory activities showed that the top home concern of CNAs was money management. CNAs ranked keeping their family healthy fourth (9.6%), and they ranked preparing fast easy meals eighth (1.7%). The top work concern of CNAs was time management. Staying healthy at work ranked fourth (12.9%), while packing a nutritious lunch was sixth (3.4%). The preferred methods of education for the participants were watching videotapes, attending classes at a central location, and having a mentor to help them with their problems.Master of Science
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Sigurdson, Gregory T. "Evaluating the Effects of Anthocyanin Structure and the Role of Metal Ions on the Blue Color Evolution of Anthocyanins in Varied pH Environments." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461253897.
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Day, Susan Marie. "Aspects of Newfoundland black bear, Ursus americanus hamiltoni, food habits and habitat use in human-influenced environments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23689.pdf.
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Banik, Milon Marc. "Performance effects of strategic groups and task environments in food manufacturing industries : augmenting the Bain-Mason paradigm." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56672.
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The concentration-profits relationship of the Bain-Mason paradigm is tested and an alternative "augmented model" is proposed which includes dimensions of task environments of food industries and industry strategy variables. The environment is characterized in terms of Dess and Beard's (1984) dimensions: munificence, dynamism and complexity.The augmented model was found to be a better descriptor of factors affecting the performance of the food industries than the Bain-Mason model. Profitability was found to be positively related to industrial concentration, and negatively related to munificence and complexity. No significant relationship between dynamism and profitability was found.
Further studies on the performance of the food manufacturing industries should include the use of strategic group typologies based on strategic behaviour specific to the food industries. It is also recommended that investigations of industry environments be conducted using multivariate measures of munificence, dynamism and complexity.
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Barss, John M. "The analysis and use of methodologies for the study of the diets of long-eared owls from three environments in north central Oregon." PDXScholar, 1985. https://pdxscholar.library.pdx.edu/open_access_etds/3437.
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Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity indices. The procedure was developed to provide a simple, easily replicated methodology for the study of pellets which also retains maximal data recorded from pellet analysis. A sample size of ten Long-eared Owl pellets was found adequate to calculate diversity indices with no significant loss of accuracy when compared to total pellets recovered from beneath a roosting site. Analysis of the total sample of pellets from a specific roost provided information on intraspecies size selection by Long-eared Owls and also increased the probability of finding remains of rare prey in pellets from the areas studied.
Part II of this study investigates the influences of seasonality and habitat differences on prey selection by Long-eared Owls in north-central Oregon. Differences in habitat where Long-eared Owls foraged were found to significantly influence prey species selection of Thomomys talpoides , Lagurus curtatus, Peromyscus maniculatus, Microtus montanus, and Perognathus parvus. Significant seasonal differences were also observed in the consumption of T. talpoides and M. montanus. Analysis of intraspecific size selection of northern pocket gophers by Long-eared Owls supports the observation that size of prey influences the foraging strategies of Long-eared Owls to a greater degree than does species composition.
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Groenewald, Willem Hermanus. "Taxonomy of species of Alicyclobacillus from South African orchards and fruit concentrate manufacturing environments and the prevention of fruit juice contamination." Thesis, Stellenbosch: University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1253.
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Thesis (PhD (Food Science))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: Species of Alicyclobacillus are acid-tolerant and heat-resistant bacteria that cause spoilage of heat-treated fruit juices stored at room temperature. During the past decade, Alicyclobacillus spp. have become a major cause of spoilage in pasteurised fruit juices leading to significant economic losses world-wide. Spoilage has been reported in apple, pear, orange, peach, mango and white grape juice, as well as in fruit juice blends, fruit juice containing drinks and tomato products, such as tomato juice and canned tomatoes. Spoilage is characterised by a medicinal smell and guaiacol production. These endospore-formers have been shown to survive pasteurisation conditions of 95 °C for 2 min, grow at temperatures between 25° and 60 °C and a pH range of 2.5 to 6.0. Knowledge of this organism is limited, both locally and internationally and the route of contamination to the final product is not well established. In this study the fruit concentrate processing environment was investigated as a potential source and route of contamination for the final product. Species of Alicyclobacillus were isolated from orchard soil, various stages during processing and from fruit juice and concentrates. The isolates were identified based on morpholological, biochemical and physiological properties. Identification to species level was done by 16S ribosomal RNA gene sequencing and strain differentiation by RAPD-PCR. Results indicate that species of A. acidoterrestris and Alicyclobacillus acidocaldarius were found in orchard soil and throughout the processing environment. This is the first report on the isolation of these species from orchard soil, vinegar flies and the fruit processing environment. The 16 isolates identified as A. acidoterrestris grouped into four clusters based on RAPD-PCR banding patterns, suggesting that they belong to at least four genotypic groups. Isolates from the fruit concentrate, wash water and soil located outside of the fruit processing plant grouped into one cluster. Concluded from these results, A. acidoterrestris found in the wash water and soil outside of the factory could act as a potential reservoir of organisms for the contamination of the final fruit concentrate. Thus good manufacturing practices play an essential role in controlling incidence of spoilage caused by these bacteria. Fruit juices can be treated using ultraviolet (UV-C) light with a wavelength of 254 nm, which has a germicidal effect against micro-organisms. Alicyclobacillus acidoterrestris spores were inoculated into tap water, used wash water from a fruit processing plant and grape juice concentrate. Ultraviolet dosage levels (J L−1) of 0, 61, 122, 183, 244, 305 and 367 were applied using a novel UV-C turbulent flow system. The UV treatment method was shown to reliably achieve in excess of a 4 log10 reduction (99.99%) per 0.5 kJ L-1 of UV-C dosage in all the liquids inoculated with A. acidoterrestris. The applied novel UV technology could serve as an alternative to thermal treatments of fruit juices for the inactivation of Alicyclobacillus spores or in the treatment of contaminated processing wash water. Finally, the thermal inactivation at 95 °C for two strains of A. acidoterrestris isolated from contaminated fruit juice concentrates were investigated in a 0.1% (m/v) peptone buffer solution (pH 7.04) and grape juice (pH 4.02, 15.5 °Brix). The thermal inactivation of A. acidoterrestris spores followed first-order kinetics, suggesting that as the microbial population is exposed to a specific high temperature, the spores inactivated at a constant rate. D-values determined in the buffer solution were calculated to be 1.92 min and 2.29 min, while in grape juice D-values were found to be 2.25 min and 2.58 min for the two strains tested. From this study it is clear that the D-value is dependant on the strain tested, but also on the soluble solids of the solution the cells are suspended in. The results indicated that the spores of A. acidoterrestris isolated from South African fruit juice concentrate may survive after the pasteurisation treatment commonly applied during manufacturing.
AFRIKAANSE OPSOMMING: Spesies van Alicyclobacillus is suur-tolerante en hittebestande bakterieë wat bederf veroorsaak in hitte-behandelde vrugtesappe wat teen kamertemperatuur gestoor word. Gedurende die afgelope dekade het Alicyclobacillus spp. ‘n belangrike oorsaak van bederf in gepasteuriseerde vrugtesappe geword en beduidende ekonomiese verliese wêreldwyd veroorsaak. Bederf is aangeteken in appel-, peer-, lemoen-, perske-, mango- en witdruiwesap, sowel as in vrugtesapversnitte, vrugtesapbevattende drankies en in tamatieprodukte soos tamatiesap en ingemaakte tamaties. Bederf word gekenmerk deur ’n medisinale reuk en guaiacol produksie. Daar is gevind dat hierdie endospoorvormers pasteurisasie teen 95 °C vir 2 min kan oorleef en kan groei by temperature tussen 25° en 60 °C en ‘n pH van 2.5 to 6.0. Plaaslik sowel as internasionaal is kennis van hierdie organisme beperk en die roete van kontaminasie van produkte is nog nie goed vasgestel nie. In hierdie studie is die vrugtekonsentraat-verwerkingsmilieu ondersoek as ‘n moontlike bron en roete van kontaminasie van die finale produk. Spesies van Alicyclobacillus is vanuit vrugteboordgrond, verskeie verwerkingstadia en van vrugtesap en vrugtesapkonsentraat geïsoleer. Die isolate is op grond van morfologiese, biochemiese en fisiologiese eienskappe geïdentifiseer. Identifikasie tot spesiesvlak is deur 16S rDNS sekwensering gedoen en stam differensiasie deur RAPD-PKR. Resultate het aangetoon dat A. acidoterrestris en A. acidocaldarius in vrugteboordgrond sowel as in alle stadia van die verwerkingsmilieu voorkom. Dit is die eerste verslag van die isolering van hierdie spesies uit die Suid-Afrikaanse vrugteverwerkingsmilieu, vrugteboordgrond en asynvlieë. Die 16 isolate, geïdentifiseer as A. acidoterrestris en in vier groepe geplaas op grond van hul RAPD-PKR bandpatrone, dui aan dat hulle aan minstens vier genotipiese groepe behoort. Isolate afkomstig van die vrugtekonsentraat, waswater en die grond buitekant die vrugteverwerkingsaanleg het een groep gevorm. Uit hierdie resultate kan afgelei word dat A. acidoterrestris, wat in die waswater en grond buite die aanleg voorkom, as ‘n moontlike bron van organismes vir die kontaminering van die finale vrugtekonsentraat kan dien. Goeie vervaardigingspraktyke speel dus ‘n noodsaaklike rol in die beheer van bederf veroorsaak deur hierdie bakterieë. Vrugtesappe kan behandel word met ultravioletlig (UV-C) met ‘n golflengte van 254 nm wat ‘n dodende effek op mikro-organismes het. Kraanwater, gebruikte waswater van ‘n vrugtesapvervaardigingsaanleg en druiwesapkonsentraat is met A. acidoterrestris spore geïnokuleer. Ultraviolet toedieningsvlakke (J L−1) van 0, 61, 122, 183, 244, 305 en 367 is aangewend met behulp van ‘n nuwe UV-C drukvloei stelsel. Daar is aangetoon dat die UV-behandelingsmetode ‘n betroubare vermindering (99.99%) van meer as 4 log10 per 0.5 kJ L-1 van ‘n UV-C dosis gee in al die vloeistowwe wat geïnokuleer is met A. acidoterrestris. Die toegepaste nuwe UV-tegnologie kan gebruik word as ‘n alternatief tot die hittebehandeling van vrugtesap vir die deaktivering van Alicyclobacillus spore of in die behandeling van gekontamineerde waswater. Ten slotte is hitte-deaktivering teen 95 °C van twee stamme van A. acidoterrestris, geïsoleer uit gekontamineerde vrugtesapkonsentraat, in ‘n 0.1% (m/v) peptoonbufferoplossing (pH 7.04) en druiwesap (pH 4.02, 15.5 °Brix), ondersoek. Die hitte-deaktivering van A. acidoterrestris spore het eerste-orde kinetika gevolg, wat aandui dat die mikrobe-populasie teen ‘n konstante tempo afsterf, wanneer blootgestel aan ‘n spesifieke hoë temperatuur. Die D-waardes in die bufferoplossing is bereken as 1.92 min en 2.29 min, terwyl daar gevind is dat die D-waardes in druiwesap 2.25 min en 2.58 min is vir die twee betrokke stamme. Vanuit hierdie studie is dit duidelik dat die D-waardes afhang van die betrokke stam, maar ook van die oplosbare vaste stowwe van die oplossing waarin die selle opgelos is. Die resultate dui daarop dat die spore van A. acidoterrestris, wat geïsoleer is uit Suid-Afrikaanse vrugtesapkonsentraat, die pasteurisasiebehandeling wat algemeen tydens vervaardiging toegepas word, kan oorleef. Aangesien die toepassing van strenger hittebehandeling om spore van A. acidoterrestris te deaktiveer onaanvaarbare organoleptiese veranderinge in die produk tot gevolg het, word dit aanbeveel dat die risiko van bederf verminder behoort te word deur die gebruik van goeie vervaardigingspraktyke gedurende vrugteverwerking.
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Valera, Martínez María José. "Development of techniques for the analysis of acetic acid bacteria populations and their interaction in different food environments." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/284451.
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El desenvolupament de tècniques moleculars per a la detecció, identificació i tipificació de bacteris acètics és la clau per a un millor enteniment de la coexistència d’aquesta microbiota relacionada amb productes alimentaris.
S’han aplicat diferents tècniques dependents e independents de cultiu per a la identificació i quantificació de bacteris acètics que es troben en raïm i vi procedents de les Illes Canàries, així com en biofilm de vinagre de maduixa. Es van detectar espècies i generes de bacteris acètics que no s’havien descrit prèviament en aquests nínxols ecològics. El disseny d’encebadors específics i sondes TaqMan-MGB en la regió del espaiador intergènic (ITS) entre els gens 16S-23S rRNA va permetre la detecció de dues espècies molt relacionades com són Acetobacter malorum i Acetobacter cerevisiae mitjançant l’ús de PCR en temps real. L’ús d’encebadors degenerats va fer possible la detecció de la presencia del gen que codifica la cel•lulosa sintasa i correlacionar aquest gen amb el fenotip de producció de cel•lulosa en bacteris acètics de diferents espècies. D’altra banda, l’escombratge funcional realitzat sobre el genoma de Komagataeibacter europaeus Gae02 va permetre la detecció de una proteïna, amb seqüència homòloga a la activitat prefenat deshidratasa, que va presentar activitat “quorum quenching”.El desarrollo de técnicas moleculares para la detección, identificación y tipificación de bacterias acéticas es la clave para una mejor comprensión de la coexistencia de esta microbiota relacionada con productos alimentarios. Se han aplicado diferentes técnicas dependientes e independientes de cultivo para la identificación y cuantificación de bacterias acéticas que se encuentran en uvas sanas y vino procedentes de las Islas Canarias, así como en biofilm de vinagre de fresa. Se detectaron especies y géneros de bacterias acéticas que no habían sido anteriormente descritos en estos nichos. El diseño de cebadores específicos y sondas TaqMan-MGB sobre la región del espaciador intergénico (ITS) entre los genes 16S-23S rRNA permitió la detección de dos especies muy relacionadas como son Acetobacter malorum y Acetobacter cerevisiae mediante PCR en tiempo real. El uso de cebadores degenerados hizo posible la detección de la presencia del gen que codifica la celulosa sintasa y correlacionar este gen con el fenotipo de producción de celulosa en bacterias acéticas de diferentes especies. Por otra parte, el screening funcional realizado sobre el genoma de Komagataeibacter europaeus Gae02 permitió la detección de una proteína, con secuencia homóloga a la actividad prefenato dehidratasa, que presentó actividad quorum quenching.
The development of molecular techniques for detection, identification and typing of Acetic Acid Bacteria is the key for a better understanding of the coexistence of this microbiota in food products. Different culture-dependent and -independent techniques were applied for the identification and the enumeration of Acetic Acid Bacteria microbiota present on healthy grapes and in wine of the Canary Islands as well as in strawberry vinegar biofilm. Species and genera of AAB not previously reported in these niches were detected. The design of specific primers and TaqMan-MGB probes in the 16S-23S rRNA gene internal transcribed region was successfully performed for the detection of the closely related species of Acetobacter malorum and Acetobacter cerevisiae using Real-Time PCR. The use of degenerated primers allowed the detection of cellulose synthase gene and the correlation of this gene with the cellulose production phenotype in AAB strains of different species. On the other hand, the functional screening in the genome of Komagataeibacter europaeus Gae02 allowed the detection of one protein, homologous to prephenate dehydratase, with quorum quenching activity.
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Mensens, Christoph. "Biodiversity and ecosystem functioning in stressed environments : primary producers and consumers at the basis of marine food webs." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066736/document.
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La biodiversité est de plus en plus modifiée par les activités humaines, ce qui a conduit à des recherches considérables sur l'effet de la biodiversité sur le fonctionnement des écosystèmes. Ces recherches ont cependant rarement inclu le stress anthropogénique qui cause la perte de biodiversité. Cette thèse analyse l'impact du stress (pesticides et métaux lourds) sur la relation entre la biodiversité et le fonctionnement des écosystèmes à la base de la chaîne alimentaire marine, avec des producteurs marins primaires (diatomées) et leurs principaux consommateurs (copépodes). Le premier résultat est que la pollution chimique altère la régularité plutôt que la richesse des espèces, avec un effet disproportionné sur le fonctionnement si un stress sélectif provoque la domination par des espèces tolérantes avec une faible contribution fonctionnelle. L'effet du stress sur le fonctionnement est prévisible sur la base d'une corrélation des traits biologiques prédisant l'abondance des espèces et des traits prédisant leur effet sur le fonctionnement. L'effet de la biodiversité sur le fonctionnement augmente sous l'effet du stress dû à une augmentation d'interactions facilitatrices entre les espèces (effet de complémentarité). L'effet du stress sur la qualité alimentaire des producteurs primaires réduit le transfert d'énergie au niveau des consommateurs, soulignant la pertinence du changement de biodiversité dans un contexte trophique. La thèse se termine par un cadre synthétique présentant les trois principaux effets (stress sélectif, stress physiologique, complémentarité) déterminant l'effet du stress sur la relation entre la biodiversité et le fonctionnement des écosystèmesBiodiversity is increasingly altered by human activities, which has led to considerable research on the consequences of biodiversity loss for ecosystem functioning. The anthropogenic stressors driving the ongoing biodiversity loss are however rarely included into biodiversity-ecosystem functioning experiments. The present thesis analyses the impact of anthropogenic stressors (pesticides, heavy metals) on the biodiversity-ecosystem functioning relation in marine primary producers (diatoms) and consumers (copepods). It was shown that chemical stress alters species evenness rather richness, with a disproportionate effect on functioning if stress causes dominance by tolerant species with a low functional contribution. Stress tolerance and the functional contribution were predictable based on the species’ biological traits, and the effects of stress on ecosystem functioning depended on the correlation of traits predicting species abundance and traits predicting the species’ effect on ecosystem functioning. The biodiversity effect on primary producer biomass production increased under stress due to facilitative interactions (complementarity effect). Stressor-induced biodiversity loss reduced the food quality of primary producers and impaired the energy transfer to the consumer level, highlighting the relevance of stressor-induced biodiversity changers in a trophic context. The thesis ends with a synthetic framework which puts forward the three main effects (selective stress, physiological stress, complementarity) through which anthropogenic stress affects biodiversity-ecosystem functioning relations at the basis of marine food webs
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Zhou, Mi. "An Examination of Celebrity Endorsement Used to Promote Branded Food and Beverage Products to American Children, Adolescents and Young Adults to Inform Policies to Promote Healthy Food Environments." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/105144.
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Celebrity endorsement is a global billion-dollar business used by food, beverage and restaurant companies to influence dietary behaviors that may contribute to overweight and obesity. Evidence suggests that existing government policies and industry self-regulatory programs in the United States (US) do not adequately protect young Americans from celebrity endorsement that promotes energy-dense and nutrient-poor food and beverage products. This PhD dissertation describes four studies that examine the nature, extent, and perceived influence of celebrity endorsement used by business firms and non-profit organizations to promote branded food and beverage products or branded campaigns to American children, adolescents and millennial young adults to inform future research and policies to promote healthy food environments. Study one created a database of US celebrities (n=732) involved with food and beverage group, brand or product endorsements (1990-2017) to examine celebrity profiles and their endorsement relationships, company partnerships, the nutritional profile of products and brands. Evidence was analyzed using Python version 3.5.5 and SPSS version 24. Study two examined celebrities associated with the Partnership for a Healthier America's Fruits and Veggies (FNV) Campaign (2015-2016). Evidence was analyzed using data visualization tools supported by Python and SPSS, and results informed the FNV Campaign. Study three used Q methodology to explore the views of Millennials, born 1981-1994 (n=40) at Virginia Tech about celebrity endorsement of food and beverage products and brands. Participants sorted 48 celebrity images depicting brand and product endorsements on a normal distribution (+4 to -4) based on celebrity trustworthiness and complete a post Q-sort questionnaire. Data analysis used PQMethod 2.35 statistical software program, centroid factor analysis, and qualitative interpretation of unique factor arrays for sorters. Study four identified relevant evidence about US celebrity endorsement of food and beverage products (2000-2019), used an accountability framework to evaluate the adequacy of accountability structures, and suggested future policies and action needed for diverse stakeholders to use celebrity endorsement to promote healthy food environments. Future research should explore the trend of celebrity endorsement used in the US marketplace and examine the influence of this marketing strategy on young people's food preferences and choices based on more representative experimental research.Doctor of Philosophy
Celebrity endorsement is a marketing strategy that represents a person who uses public recognition to promote the sales, use or consumption of a brand, product, or service. Celebrity endorsement has been used by food, beverage and restaurant companies to influence eating behaviors that may contribute to overweight and obesity. Evidence suggests that existing government policies and industry self-regulatory programs in the United States (US) do not adequately protect young Americans from celebrity endorsement that promotes energy-dense and nutrient-poor food and beverage products. This PhD dissertation describes four studies that examined the nature, extent, and perceived influence of celebrity endorsement used by business firms and non-profit organizations to promote branded food and beverage products or branded campaigns to American children, adolescents and millennial adults to promote healthy food environments. Study one created a database of US celebrities (n=732) involved with food and beverage group, brand or product endorsements (1990-2017) to examine celebrity profiles and their endorsement relationships. Evidence was analyzed using Python data visualization tools and SPSS statistical software. Study two examined celebrities associated with the Partnership for a Healthier America's Fruits and Veggies (FNV) Campaign (2015-2016). Evidence was analyzed using baseline celebrity data (n=82) provided by the campaign initiator, and results informed the FNV Campaign. Study three used Q methodology to explore the views of Millennials, born 1981-1994 (n=40) at Virginia Tech about celebrity endorsement of food and beverage products and brands. Participants sorted 48 celebrity images depicting brand and product endorsements based on celebrity trustworthiness and complete a post Q-sort questionnaire. Data analysis used PQMethod 2.35 statistical software to generate shared viewpoints. Study four identified relevant evidence about US celebrity endorsement of food and beverage products (2000-2019), used an accountability framework to evaluate the adequacy of accountability structures, and suggested future policies and action needed for diverse stakeholders to use celebrity endorsement to promote healthy food environments. Future research should explore the trend of celebrity endorsement used in the US marketplace and examine the influence of this marketing strategy on young people's food beverage preferences and choices based on more representative experimental research.
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Knoll, Megan. "Survey methodology and prevalence estimates from the SPAACE (surveying the prevalence of food allergy in all Canadian environments) study." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107868.
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Introduction: Low income, less educated and immigrant populations are notorious for having low response rates in research studies. Therefore, it is not surprising that when attempting to estimate food allergy prevalence in Canada, the SCAAALAR study (Surveying Canadians to Assess the Prevalence of Common food Allergies and Attitudes towards food LAbeling and Risk), which attained a response rate of only 34.6% , underrepresented several vulnerable populations (those of low socioeconomic status, non post-secondary graduates, new Canadians, residents of the territories and Aboriginals).Objective: The objective of this thesis is two fold: 1) to determine an effective methodology for obtaining high response rates in the vulnerable populations not adequately represented in SCAAALAR and 2) to attain food allergy prevalence estimates for these vulnerable populations.Methods: To increase response rates and adequately sample the desired populations, a pilot study was conducted to evaluate the effect of unconditional incentives in vulnerable populations for a telephone survey. Households in low income/high immigrant postal codes were randomly selected and randomly assigned to receive either an unconditional incentive or no incentive. The difference in response rate and 95% confidence interval was calculated using a normal approximation to the difference of two binomial distributions. The pilot study informed the methodology employed in the SPAACE study (Surveying the8Prevalence of Food Allergy in All Canadian Environments), which subsequently addressed the second objective of this Thesis. SPAACE then estimated the prevalence of food allergy for those of low socioeconomic status, non post-secondary graduates, new Canadians, residents of the territories and Aboriginals. Prevalence estimates among vulnerable populations were compared to their comparator populations (i.e., those of high socioeconomic status, post-secondary graduates, individuals born in Canada, residents of the provinces and non-Aboriginals); between population differences and 95% confidence intervals were calculated using normal approximations to the difference of two binomial distributions.Results: The response rates were 38.4% and 31.4% for the incentive and non-incentive groups respectively, with a between group difference of 0.070 (-0.013, 0.15). The cooperation rates, which exclude non-contacts from the calculation, were 47.3% and 40.0% for the incentive and non-incentive group respectively, with a between group difference of 0.073 (-0.023, 0.17). Prevalence estimates for those of low socioeconomic status, new Canadians and Aboriginals were lower than their comparator population's prevalence (between population differences respectively: -2.44% (95% CI: -3.52%, -1.35%); -2.66% (95% CI: -3.5%, -1.82%); -2.17% (95% CI: -3.18%, -1.16%)) .Discussion: Although wide confidence intervals preclude definitive conclusions, our results suggest that unconditional incentives are an effective means of9increasing response rates in vulnerable populations for telephone surveys. Additionally, the results of SPAACE demonstrate that socioeconomic status, birthplace and ethnicity are associated with the prevalence of food allergy. These findings are indicative of potential lifestyle, cultural, and genetic factors that may influence the development of food allergy.Introduction : Les populations immigrantes, moins nanties and moins éduquées sont reconnues comme ayant des taux de réponses peu élevés lors d'études. Il est alors peu surprenant de constater que l'étude SCAAALAR (Surveying Canadians to Assess the Prevalence of Common food Allergies and Attitudes towards food LAbeling and Risk), qui a atteint un taux de réponse de seulement de 34.6%, ait sous-représenté plusieurs groupes de la population (ceux de statut socioéconomique moins élevé, de non-gradués postsecondaire, de nouveaux arrivants au Canada, de résidents des territoires et des amérindiens). Objectif : L'objectif de cette thèse est en deux parties : 1) déterminer une méthodologie efficace pour obtenir un haut taux de réponse au sein des populations vulnérables mal-représentées avec SCAAALAR et 2) obtenir des estimés de prévalences d'allergies alimentaires pour ces populations vulnérables. Méthodologie : Pour améliorer les taux de réponse et de sonder adéquatement les populations désirées, une étude pilote a été réalisée pour évaluer les effets des incitatifs inconditionnels sur les populations vulnérables lors d'un sondage téléphonique. Les ménages situés dans les codes postaux à faibles revenus et à haute présence d'immigrants ont été sélectionnés et assignés de manière aléatoire à recevoir un incitatif inconditionnel ou à ne pas en recevoir. La différence du taux de réponse et de l'intervalle de confiance à 95% a été calculé en utilisant une approximation normale jusqu'à 2 distribution binômes. L'étude pilote a informé la11méthodologie employée dans l'étude SPAACE (Surveying the Prevalence of Food Allergy in All Canadian Environments), qui a par la suite adressé le deuxième objectif de cette thèse. SPAACE a ensuite estimé la prévalence d'allergies alimentaires pour les populations non graduées d'études postsecondaire, les immigrants, les résidents des territoires et des amérindiens. Les estimés de prévalences au sein des populations vulnérables ont été comparés à leurs populations comparatives (i.e., celles de statut socioéconomique plus élevé, les gradués postsecondaire, les canadiens nés au pays, les résidents des provinces et des non-Amérindiens); les différences entre populations et les intervalles à 95% de confiance ont été calculés en utilisant des estimés normaux de différences entre 2 distributions binômes.Résultats : Les taux de réponse ont atteint 38.4% et 31.4% pour les groupes avec et sans incitatifs, respectivement, avec une différence entre groupes de 0.070 (-0.013, 0.15). Les taux de coopération, ce qui exclu les non-contacts des calculs, ont été de 47.3% et 40.0% pour les groupes avec et sans incitatifs, respectivement, avec une différence entre groupes de 0.073 (-0.023, 0.17). Les estimés de prévalences pour les populations de statut socioéconomique moins élevé, les immigrants, et les amérindiens étaient moins élevés que les prévalences de leurs populations comparatives (différences entre populations, respectivement : -2.44% (95% CI : -3.52%, -1.35%); -2.66% (95% CI : -3.5%, -1.82%); -2.17% (95% CI : -3.18%, -1.16%)).12 Discussion : Bien que de larges intervalles de confiance excluent des conclusions définitives, nos résultats suggèrent que des incitatifs inconditionnels sont une manière efficace d'augmenter le taux de réponse lors de sondages téléphoniques auprès des populations vulnérables. De plus, les résultats de SPAACE démontrent que le statut socioéconomique, le lieu de naissance et l'ethnie sont associés à la prévalence des allergies alimentaires. Ces découvertes indiquent que des facteurs culturels, génétiques et des habitudes de vie peuvent influencer le développement des allergies alimentaires.
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Spires, Mark Haydn. "Community insights into, and an international perspective on the role food environments and diet play in the self-management of type 2 diabetes mellitus in urban and rural South Africa." The University of the Western Cpae, 2018. http://hdl.handle.net/11394/6470.
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Philosophiae Doctor - PhDType 2 diabetes mellitus (T2DM) and pre-diabetes contribute increasingly to the global burden of disease. Along with other behavioural risk factors, diet plays a key role in the onset and management of the disease, in turn largely determined by what foods are immediately accessible in local food environments. With this in mind, this thesis aims to answer the research question: What role do local food environments play in promoting or inhibiting access to healthy foods as part of the self - management of T2DM in urban and rural communities in South Africa, and what can be learned from an international perspective? Specific research objectives include, to: 1. Understand the current national-level policy context with regard to the observed rise in NCDs, their proximal determinants (specifically an observed change in diet patterns), and contributing environmental factors; 2. Identify the current food-related environmental factors associated with the onset and/or management of T2DM in an urban and a rural setting (as well as in four additional international settings in order to provide an international perspective); 3. Explore community perspectives of the role the local food environment plays in the self-management of T2DM in an urban and a rural setting; and, consequently 4. Recommend intervention- and/or policy-related actions that can be implemented based on study findings. A review of the literature and relevant policies was conducted towards achieving the first research objective. Quantitative data were systematically collected at an urban and rural site in South Africa through the creation of an ‘environmental profile’ in an attempt to achieve the second objective – comparable urban and rural data was also collected as part of a larger study at two other international sites (Kampala, Uganda and Stockholm, Sweden) to provide an international perspective. Included in the third objective is the collection of qualitative data through a community based participatory research method at the same urban and rural sites in South Africa. Finally, intervention and/or policy-related recommendations are developed based on study findings and in consultation with relevant stakeholders through interviews.
2018-12-14
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Manuga, Tshilidzi. "The relationship between food environment, obesity and NCD status among adults aged 30-70 years in Langa and Mount Frere, South Africa." University of Western Cape, 2019. http://hdl.handle.net/11394/7637.
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Master of Public Health - MPHNon-Communicable Diseases (NCDs) are some of the leading causes of death worldwide. Obesity results from the interactions between biology, behaviour, and environment. The current obesity epidemic is largely driven by environmental rather than biological factors, through its influence on social norms regarding food choices and lifestyle behaviours. The number of people dying from diabetes and hypertension keeps increasing because of the current obesity trend.
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McKnight, Julie. "Trophic enrichment patterns of d 13C in organic matter of molluscan shell: Implications for reconstructing ancient environments and food webs." Scholar Commons, 2009. http://scholarcommons.usf.edu/etd/2097.
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Shell organic matrix proteins in fossils are valuable geochemical archives for studying ancient environments and food webs. Compound-specific studies of stable carbon isotope ratios offer particularly good resolution of trophic level of consumers and the identities of primary producers and can be used to detect diagenetic alteration of isotopic ratios. To interpret compound specific isotope data, however, controlled diet studies in the laboratory are needed to reveal trophic enrichment patterns of 13C in tissues and shell organic matter. This study examines the relationship between d 13C of 11 amino acids in diet, soft tissues, and shell organic matter in laboratory-cultured Strombus alatus, an herbivorous marine gastropod. The d 13C values of amino acids in this animal's foot and mantle tissues are consistently enriched in 13C relative to the diet.
Phenylalanine (+1.8 ppm) and alanine (+3.8 ppm) showed the least fractionation between diet and tissues, while aspartic acid (+10.7 ppm) and glutamic acid (+14.6 ppm) showed the greatest enrichment. On average, nonessential amino acids exhibited greater enrichment than did essential amino acids (+7.1 ppm vs. + 4.1 ppm). Shell organic matter amino acids showed a very similar pattern, with aspartic and glutamic acids again showing the greatest enrichment (+7.2 ppm and +11.1 ppm respectively). Nonessential amino acids in shell (+4.9 ppm) were also more enriched than the essential amino acids (+3.5 ppm). Overall, the carbon isotopic compositions of amino acids in shell organic matrix appear to parallel those in animal tissue, validating the utility of employing this material as a surrogate for animal tissue in fossil samples.
Interpreting trophic position information in consumers is difficult, however, as the variation in the magnitude of trophic enrichments for glutamic and aspartic acids between species, tissue types and diet is still poorly understood. As phenylalanine has the most consistent diet-consumer enrichments, the most suitable application for d 13C isotope analysis at this time is the reconstruction of base food sources.
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Li, Jingjing. "Understanding the Effects of Built Environments in Different Spatial Contextual Units on Individuals’ Health-related Behaviors." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin154410042185049.
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Yi, Yue. "Characterization of Salmonella Bacteriophages Isolated from Farm Environments for Use in Decontamination of Liquid Whole Egg." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1566222931949046.
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Maas, Sylvana, and n/a. "Population dynamics and control of feral goats in a semi-arid environment." University of Canberra. Resource, Environmental & Heritage Sciences, 1997. http://erl.canberra.edu.au./public/adt-AUC20060825.132138.
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The ability of feral herbivores to reduce the amount of food available to domestic livestock has
rarely been quantified. This thesis seeks to examine the degree to which feral goats (Capra
hircus) reduce the availability of pasture and shrub biomass for other herbivores. The
interaction between feral goat populations and their food supply will be explored using a
modelling approach. In addition to this it will also examine the cost of controlling goats and
attempt to identify the cost efficient target densities for control operations. The implications of
this information for management will be discussed.
There are two ways an animal population can interact with its food supply, through: (1)
intrinsic food shortages, and (2) extrinsic food shortages. Intrinsic food shortages occur when a
negative feed-back loop exists between the animal population and their food supply. This
means the animals affect the availability of their food and their food supply affects the
dynamics of the animal population. Since the animals are affecting their own food supply it
could be said that they will also affect the availability of that food to other herbivores if they
consume the same species. Extrinsic food shortages occur when there is no feed-back from the
animals to their food supply. Food availability is determined by extrinsic factors such as
rainfall and is unaffected by the animal population. To determine how feral goats interact with
their food supply several models will be examined, and these include: (1) single species models
which use data from the animal population only. These have historically been used to identify
density dependence which is commonly caused by the animal population being regulated
through their food supply in the case of large herbivores, and (2) trophic models which
incorporate data from at least two trophic levels in an ecosystem, in this case those being the
animal population and the vegetation they are thought to consume. These models allow a more
direct examination of the relationship between the feral goat population and their food supply.
The various models were fitted to data collected on the field sites and the following results
were obtained:
(1) the dynamics of the feral goat populations could not be represented by single-species
models. This was most probably due to the stochastic environment in which they lived
causing the level of density dependence experienced by the goats to vary greatly masking its
presence.
(2) the rate of increase of the goat population could be predicted by the numerical response of
rate of increase to pasture biomass. This demonstrated that food availability influenced the
dynamics of the goat population.
(3) goat density affected the availability of some species of shrub biomass. There was,
however, no response seen in the availability of pasture species to changes in goat density.
Since the study was conducted during a drought this is in agreement with other studies
which indicated that goats will primarily browse during dry spells but switch to pasture
species when conditions improve following rainfall.
These results indicate that a negative feed-back loop does exist between feral goat populations
and their food supply since the goats affected the availability of some shrub species and so they
suffer intrinsic food shortages. This means goats have the ability to reduce the availability of
food to other herbivores providing both are eating the same species.
Cost-efficiency analysis showed that the cost of removing individual feral goats increases
exponentially as density decreases because the search time per animal becomes greater. This
relationship was used to construct a model that predicted the cost of achieving a target density.
The model describing cost of control over density was also combined with a productivity
model based on the numerical response of feral goats to pasture biomass to predict the cost of
maintaining target densities under different environmental conditions. Using these models the
most cost-efficient density identified was 11 goats/km2.
From this study we can make the following conclusions:
(1) feral goats have the ability to reduce the amount of shrub biomass available to other
herbivores during dry conditions
(2) their ability to influence the availability of pasture species remains unknown
(3) given the cost of initial and ongoing control and the minimal benefits that result it would be
difficult to justify controlling goats during a drought on the field sites.
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Abaid, Mohammed. "Evaluation of Jatropha Curcas as future en-ergy crop in some African countries." Thesis, KTH, Mark- och vattenteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170063.
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Biofuels now days consider as one of the successful alternative to meet the challenges associated with climate change and peak oil, as well as a way for poorer countries to develop an industry in order to enhance social and economic development. In many developing countries and particularly in Africa, this has led to large-scale investments in lands by foreign companies, and as a consequence there has been a debate on whether these actions are environmentally sustainable and whether this kind of activity actually brings economic development. The investments of biofuels in Africa, espe-cially the Jatropha plantations are debatable. Several arguments have been concentrat-ed on development goals, economic issues and environmental concerns. This report evaluates the status of some Jatropha projects in Sudan, Ethiopia, Kenya and Tanza-nia, the outcomes of the report show that biofuels from Jatropha lead to a significant socio -economic benefits by creating many jobs opportunities and improve the stand-ard of living in Africa. However, inadequate funding’s, high investment costs, no clear policies for biodiesel are the most challenging for Jatropha in Africa which need fur-ther mechanisms and ideology by African scientists, leaders, NGOs, farmers and deci-sion makers. In the studied countries, it was reported that the Jatropha produce low yields of oil seeds especially in the marginal lands with no enough water supplies. In Kenya the productivity of Jatropha is very low for large scale- project. Moreover some social and environmental impacts are also seen for Jatropha cultivations in Ethiopia, Kenya and Tanzania. Some Jatropha projects have impacted the food security nega-tively; nevertheless some biofuels experts believe that Jatropha has no any adverse im-pacts on food security since it is inedible and grown on marginal lands. In Ethiopia, the main environmental impacts of Jatropha are related to biodiversity, water quality and quantity. In Kenya, the environmental impacts are related to biodiversity, carbon emissions, water withdrawal, pollution of agro- chemicals usage, deforestation and soil erosion, whereas in Tanzania, the main environmental issues are connected to the change of land use system, impacts on biodiversity and impacts on water resources.
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Swaffield, James B. "Environmental harshness and its effect on appetite and the desire for conspicuous signalling products." Thesis, University of Stirling, 2017. http://hdl.handle.net/1893/27239.
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There is often an assumption that there is a right and a wrong way for consumers to behave. For example, with regard to eating, people should make food choices based on maximizing vitamins and minerals and not consuming more calories than one expends in a day. Likewise, it is assumed that buying products to conspicuously signal a message to another is wasteful and maladaptive. The research in this thesis challenges these assumptions and argues that these behaviours can be both adaptive and maladaptive depending on one’s environmental conditions. In this thesis, I describe three experiments that examine how perception of environmental harshness affects appetite for different types of foods. The data shows that food desirability in adulthood varies depending on early childhood socio-economic status, the type of environmental stressor (harsh social, harsh economic and harsh physical safety) and the intensity of the stressors within each of these environments. It was also found that different types of environmental harshness differentially affects food desire based on energy density and food category type. In addition to the experiments on harshness and food desirability, I have examined how environmental harshness affects desire for products that are used to conspicuously signal information to others. For example, under conditions of environmental stress, products may be used to advertise that a male possesses financial or physical power which is desirable to a potential mate. Likewise, a women may buy products to display she possess financial power or she may purchase products that augment her beauty and sexual attractiveness. These studies reveal that product desire is also affected by different types of environmental harshness and the intensity of the stress generated by these environmental conditions. Through the research described in this thesis, we gain a more comprehensive understanding of the proximate variables that influence two subsets of consumer behaviour, namely food desire and product signalling, and how these behaviours may have been selected for due to their adaptive value.
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Huynh, Mongkieu Thi. "The Effect of School Policies and Practices and Food Environments on Fruits and Vegetables Selected from Salad Bars among U.S. Elementary Schools." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1405340224.
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Kane, Deborah M. "Evaluation of a sanitizing system using isopropyl alcohol quaternary ammonium formula and carbon dioxide for dry-processing environments." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/14175.
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Master of ScienceFood Science
Kelly J. K. Getty
Dry-processing environments are particularly challenging to clean and sanitize because water introduced into systems not designed for wet cleaning can favor growth and establishment of pathogenic microorganisms such as Salmonella. The objective was to determine the efficacy of isopropyl alcohol quaternary ammonium (IPAQuat) formula and carbon dioxide (CO[subscript]2) sanitizer system for eliminating Enterococcus faecium and Salmonella on food contact surfaces. Coupons of stainless steel and conveyor belting material used in dry-processing environments were spot-inoculated in the center of 5 × 5 cm coupons with approximately 7.0 log CFU/ml of E. faecium and up to 10 log CFU/ml of a six-serotype composite of Salmonella and subjected to IPAQuat-CO[subscript]2 sanitation treatments using exposure times of 30 s, 1 or 5 min. After sanitation treatments, wet coupons were swabbed for post-treatment survivors. Preliminary experiments included coupons which were soiled with a flour and water solution prior to inoculation and subsequent sanitation treatments. For the main study, inoculated surfaces were soiled with a breadcrumb flour blend and allowed to sit on the lab bench for a minimum of 16 h before sanitation. Preliminary results showed that IPAQuat-CO[subscript]2 sanitizing system was effective in reducing approximately 3.0 logs of E. faecium and Salmonella from clean and soiled surfaces after 1 min exposure but higher initial inoculum levels were needed to demonstrate >5 log reductions. For the main study, pre-treatment Salmonella populations were approximately 7.0 log CFU/25 cm[superscript]2 and post-treatment survivors were 1.3, < 0.7 (detection limit), and < 0.7 log CFU/25 cm[superscript]2 after 30 s, 1 or 5 min sanitizer exposures, respectively, for both clean and soiled surfaces. Treatment with IPAQuat-CO[subscript]2 sanitation system using 30 s sanitizer exposures resulted in 5.7 log CFU/25 cm[superscript]2 reductions whereas, greater than 6.0 log CFU/25 cm[superscript]2 reductions were observed for sanitizer exposures of 1 and 5 min. The IPAQuat-CO[subscript]2 sanitation system reduced 6 logs CFU/25 cm[superscript]2 of Salmonella with sanitizer exposure times of at least 1 min. The IPAQuat-CO[subscript]2 system would, therefore, be an effective sanitation system to eliminate potential contamination from Salmonella on food contact surfaces and have application in facilities that process dry ingredients or low-moisture products.
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Pillay, Vasanti. "Evaluation of the impact of the integrated food and nutrition programme in Kungwini." Thesis, University of Pretoria, 2010. http://hdl.handle.net/2263/29007.
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The poor in South Africa encounter many obstacles that impact negatively on their wellbeing. These include high rates of unemployment and a lack of financial and material resources. The poor living in informal settlements dwell in conditions that have an adverse impact on family health, due to malnutrition and food insecurity. Post 1994, many poverty alleviation programmes, including the Integrated Food and Nutrition Programme (IFNP) sought to improve the lives of the poor. The objective of the IFNP was to address poverty in Kungwini by increasing household food and income to enable poor households to attain a better standard of living. The purpose of this research is to evaluate whether the IFNP had achieved its objective to reduce poverty in Kungwini and whether programme implementation was effective. Social development, a process of planned social change to promote the well-being of the population, including economic development, formed the theoretical base for the research study. Social development aims to link the promotion of human welfare and economic development, and to make development socially relevant. Policies and programmes such as the IFNP aim to enhance people’s welfare and contribute to economic development. The literature study included the impact of global and national poverty on poor households in terms of poverty levels and unemployment. Gender discrimination and the social marginalization of vulnerable groups which include children, the youth, the aged and the disabled poor, social justice for the poor and the gap between the formal and informal sectors informed the research process. The crucial need for collaborative partnerships to address poverty issues is stressed, including the involvement of the poor in policy processes that impact on their wellbeing and the importance of reviewing policy implementation processes through regular programme evaluation. Poverty challenges include skills development for employment; food security; and policy reforms to ensure effective service delivery. Appropriate skills development should be identified in consultation with the poor. It is imperative that policy makers are equipped with adequate policy development skills to develop stakeholder participation. Efficient communication between relevant departments and community organisations will maintain the collaborative partnership. Public policy implementation and project management remain inter-dependent processes. Public poverty policies are based on the specific Department’s focus. Consequently, fragmented services are rendered by various public sectors, targeting the similar beneficiaries. The IFNP is evaluated against essential policy requirements to create an enabling service delivery environment and programme coordination. This includes good governance, transparency, public participation, and sustainable policy implementation. Achieving a balance between effective service delivery; adequate resources, and efficient monitoring and evaluation processes highlight the principles of successful poverty policies. Evaluation research with a combined qualitative and quantitative research approach was utilized to gather data to evaluate the impact of the IFNP to reduce poverty in Kungwini. The collective case study design was used for the qualitative research and data was collected through focus group interviews. A questionnaire was the data collection method for the quantitative research. The research results indicated that the IFNP’s objective to address poverty in Kungwini required interactive participation from relevant departments and community organisations. The collaborative partnership is essential to address poverty effectively. Research findings include the need to equip the poor with relevant skills for the job market, or to develop their own businesses. Youth mentoring is essential to enable the youth to pursue future goals. Small scale farmers should be trained with improved farming methods. Access to financial institutions and trading markets would improve the economic circumstances of the informal sector. Collaborative partnerships with a range of stakeholders, including the poor, would ensure effective service delivery through shared responsibilities. Service delivery should be based on achievable goals and effective communication strategies. Public policy developers require adequate policy development knowledge and policy implementation skills to ensure cost-effective policy processes. The research recommendations indicate that the Integrated Model is more cost effective than the Organizational Model to reduce poverty as it includes stakeholder involvement in policy development and policy advocacy. Maintaining communication between relevant departments and community organizations remain key policy requirements. Ensuring personnel training in practical project management skills is an essential policy necessity. Appropriate skills development should be identified in consultation with the poor. Efficient communication between relevant departments and community organizations will maintain the collaborative partnership. Policy implementation processes should be regularly reviewed to address policy constraints. Personnel training include policy and practical project management skills to ensure transparency and cost-effective service delivery. Addressing policy constraints through alternative policy options will ensure programmes are on track to achieve policy goals and objectives.Thesis (DPhil)--University of Pretoria, 2011.
Social Work and Criminology
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Nestola, Marco [Verfasser], and Torsten Claus [Akademischer Betreuer] Schmidt. "Multidimensional high-performance liquid chromatography–gas chromatography (HPLC-GC) hyphenation techniques for food analysis in routine environments / Marco Nestola ; Betreuer: Torsten Claus Schmidt." Duisburg, 2016. http://d-nb.info/1115654659/34.
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Glass, Jordan R. "Should I stay or should I go? Complex environments drive the developmental plasticity of flight capacity and flight-related tradeoffs." Scholarly Commons, 2018. https://scholarlycommons.pacific.edu/uop_etds/3535.
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Animals must balance multiple, fitness-related traits in environments that are complex and characterized by co-varying factors, such as co-variation in temperature and food availability. Thus, experiments manipulating multiple environmental factors provide valuable insight into the role of the environment in shaping not only important traits (e.g., dispersal capacity or reproduction), but also trait-trait interactions (e.g., trade-offs between traits). We employed a multi-factorial design to manipulate variation in temperature (constant 28°C vs. 28±5°C daily cycle) and food availability (unlimited vs. intermittent access) throughout development in the sand field cricket, Gryllus firmus. We found that fitness-related, life-history traits and trait trade-offs can be developmentally plastic in response to variation in temperature and food availability. Variability in temperature and food availability influenced development, growth, body size, reproductive investment, and/or flight capacity, and food availability also affected survival to adulthood. Further, both constant temperature and unlimited food availability promoted investment into key components of somatic and reproductive tissues while reducing investment into flight capacity. We develop an experimental and statistical framework to reveal shifts in correlative patterns of investment into different life-history traits. This approach can be applied to a range of animal systems to investigate how environmental complexity influences traits and trait trade-offs.
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Olofsson, Terése, and Hanna Pettersson. "I en stödjande miljö är hälsosamma val enkla val : En kvantitativ studie om konsumenters upplevelser av hälsosamma livsmedelsval." Thesis, Luleå tekniska universitet, Institutionen för hälsovetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79281.
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Introduktion: Ohälsosamma matvanor är en av de största riskfaktorerna för ohälsa och förekommer oftare i socioekonomiskt svagare grupper. Tillgängligheten av livsmedel påverkar både vilka kostval vi gör och hur mycket vi konsumerar. Marknadsföring påverkar tillgängligheten och används för att styra konsumenternas livsmedelsval. För att främja hälsosamma val behövs stödjande miljöer med tillgängliga, prisvärda och hälsosamma livsmedel. Syfte: Syftet är att undersöka hur hälsosamma livsmedelsval har samband med konsumenters upplevelser av dagligvaruhandelns bidrag till stödjande miljöer för hälsosamma livsmedelsval. Metod: En kvantitativ tvärsnittsdesign tillämpades. Datainsamlingen skedde genom webbenkät vilken länkades till informanter via sociala medier. Deskriptiv analys användes samt positiv oddskvot för att belysa det salutogena perspektivet. Ett p-värde på <0,05 ansågs signifikant. Resultat: Respondenterna (n=346) var kvinnor och män över 21 år. Majoriteten var kvinnor i medelåldern, med högskole- eller universitetsexamen samt medelinkomst. Konsumenter som väljer hälsosamma livsmedel har samband med sinnesstämning, naturliga livsmedel och tillgänglighet. Slutsats: Det är viktigt att hälsofrämjande insatser riktas mot hela samhället och stärker medvetenheten om hälsosam kost. Då studien visade samband mellan konsumenters upplevelser av dagligvaruhandelns stödjande miljöer och hälsosamma livsmedelsval, bör hela livsmedelskedjan medvetandegöras om hur folkhälsan påverkas av stödjande miljöer.Introduction: Unhealthy eating habits are one of the major risk factors för unhealth and occur more frequently in low socioeconomic areas. The availability of food affects both the dietary choices we make and how much we consume. Marketing affects accessibility and is used to guide consumers' food choices. In order to promote healthy choices, supportive environments with available, affordable and healthy foods are needed. Aim: The aim is to investigate how healthy food choices are linked to consumers' experiences of the grocery retailer's contribution to supportive environments for healthy food choices. Methods: A quantitative cross-sectional design was applied. Data was collected with a web survey. Descriptive analysis applied as well as logistic regression analysis and positive odds ratio was used to illustrate the salutogenic perspective. A p-value of <0.05 was considered significant. Result: The respondents (n = 346) were women and men over 21 years. The majority were middle-aged women, with a college or university degree and middle income. There is an association between consumers who choose healthy foods and mood, natural foods and availability. Conclusion: It is important that health promotion efforts are directed at the entire society and strengthen the awareness of healthy eating. As the study showed a correlation between consumers' experiences of the grocery's supportive environments and healthy food choices, the entire food supply chain should be made aware of how public health is affected by supportive environments.
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Tyrrell, Rachel Louise. "Exploring adolescent food choice : a food environment perspective." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2530.
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Obesity is a significant problem in young people. Relative to other age groups, less is known about health related lifestyle behaviours of young people, particularly in the transition period from adolescence to adulthood. Food choices are made within the food environment, which encompasses any opportunity to obtain food or influence food choice. Environmental exposures such as the availability and accessibility of ‘more healthy’ and ‘less healthy’ food options interact with individual factors to drive food choice. The aim of this work was to explore whether, and to what extent, the food environment to which a young person is exposed has an influence on individual dietary intake. A range of methods including food diaries in conjunction with text messaging and photography, questionnaires, Global Positioning Systems (GPS), Geographical Information Systems (GIS), and qualitative interviews were used. The majority of young people (96%) reported using a food outlet at least once over a 4-day period. Less healthy food outlets, such as takeaways and convenience stores, were the most frequently used. Being exposed to a greater number of food outlets was significantly associated with visiting a greater number of food outlets. Similarly, being exposed to a greater proportion of ‘less healthy’ food outlets was associated with visiting a greater proportion of ‘less healthy’ food outlets. However, relationships between the number of food outlets visited and dietary intake were weak and there was little evidence to suggest an association between exposure to food outlets and dietary intake. Qualitative results indicated that time, geographic location, economic cost and social occasion influenced choice of food outlet. In addition, the particular food outlet chosen appeared to dictate the food choices made with habitual repeat ordering of meals an emerging theme. No previous research has linked individual eating behaviour to the food environment. Identifying the types of outlets young people use, the food choices made within and the factors influencing decisions and behaviours is important for the development of targeted long term obesity prevention strategies to facilitate healthier food outlet environments.
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Nitta, Caitlin Nicole. "Environment's Effects on Food Impulse Control." Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/144914.
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