261 |
Strategies to Improve Quantitative Proteomics: Implications of Dimethyl Labelling and Novel Peptide DetectionBoutilier, Joseph 21 March 2012 (has links)
In quantitative proteomics, many of the LC-MS based approaches employ stable isotopic labelling to provide relative quantitation of the proteome in different cell states. In a typical approach, peptides are first detected and identified by tandem MS scans prior to quantifying proteins. This provides the researcher with a large amount of data that are not useful for quantitation. It is desirable to improve the throughput of current approaches to make proteomics a more routine experiment with an enhanced capacity to detect differentially expressed proteins. This thesis reports the developments towards this goal, including an assessment of the viability of stable dimethyl labelling for comparative proteomic measurements and the evaluation of a dynamic algorithm called Parallel Isotopic Tag Screening (PITS) for the detection of isotopically labelled peptides for quantitative proteomics without the use of tandem MS scans.
|
262 |
A study of proteinases of invasive cells using cryoultramicrotomy and immunogold labelling.Elliott, Edith. January 1993 (has links)
This study forms part of an investigation into the possible relevance of the
lysosomal proteinases, cathepsins B, H, Land D, in cancer cell invasion. In this
study, the main technique adopted was the Tokuyasu "cryo" method, in which the
tissues were fixed, frozen and sectioned and labelled using the relevant antibodies,
which were detected with protein A gold probes.
In order to implement the Tokuyasu technique, it was necessary to rebuild a knife
maker, for the production of adequately sharp glass knives, and to modify a sputter-coater
into a glow-discharger, for rendering carbon-coated grids hydrophilic, to
promote adhesion of hydrated sections.
This study was directed towards human tissues and peptide antibodies were
investigated as a means of avoiding isolation of proteins from scarce human tissue,
and as a means of obtaining antibodies that will target specific regions of proteins of
interest. Peptide antibodies were also considered promising for studies of
proteinase trafficking and as immunoinhibiting agents, potentially useful in cancer
therapy. Various prediction programmes were investigated for their effectiveness
in predicting whether a given peptide sequence will elicit antibodies that will react
with the native protein. Successful prediction would increase the success rate of
peptide antibody production and thus lower the cost.
Leucocytes were studied as a model of an invasive cell, since they are more readily
available than tumour cells and serve the purpose during the development of
methods. In the course of these studies, an optimal protocol for the fixation of
PMNs was developed, involving lateral fixation of cut sections, that should be
useful for future studies on these cells. Elastase and cathepsins D and G were found
on the surface of activated PMNs and could thus play a role in the invasive
properties of these cells.
Studies on MCF-10A "normal" breast epithelial cells and their ras-transformed
Neo-T counterparts revealed that upon transformation, lysosomes shift from a
perinuclear position, to a more peripheral position. None of the cathepsins studied
was found on the cell surface of either the normal or ras-transfected cells,
suggesting that surface distribution of these enzymes may not be a requirement for
invasiveness. These studies suggest that immunocytochemical investigation of
cells, in the process of invading through a barrier membrane, might be profitable in
elucidating the role of proteinases in invasive cancer. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1993.
|
263 |
Using Flow Cytometry to Evaluate the Functionalization and Targeting of Surface Enhanced Raman Scattering NanoparticlesMullaithilaga, Nisa 15 November 2013 (has links)
The effective diagnosis of leukemia subtypes requires the detection of multiple cell surface markers. Current methods of detection use mostly fluorophores, which are limited by their large spectral bandwidths, photobleaching, and incompatibility with histological stains used for morphological assessments. Antibody-conjugated Surface enhanced Raman scattering (SERS) nanoparticles is an alternative tool that overcomes these limitations. A current drawback of SERS is the lack of available tools to analyze the bioconjugation of antibodies to nanoparticles following EDC/sulfo-NHS cross-linking, which produces inconsistent results and determines the efficacy of SERS probe targeting. This study uses the flow cytometry approach to evaluate SERS particles by incorporating FITC and DyLight650 secondary antibodies. Flow cytometry was also used to assess targeting of particles to markers on LY10 cells and CLL cells and to detect SERS signals by inserting a 710 BP 10nm FWHM filter specific for MGITC.
|
264 |
Using Flow Cytometry to Evaluate the Functionalization and Targeting of Surface Enhanced Raman Scattering NanoparticlesMullaithilaga, Nisa 15 November 2013 (has links)
The effective diagnosis of leukemia subtypes requires the detection of multiple cell surface markers. Current methods of detection use mostly fluorophores, which are limited by their large spectral bandwidths, photobleaching, and incompatibility with histological stains used for morphological assessments. Antibody-conjugated Surface enhanced Raman scattering (SERS) nanoparticles is an alternative tool that overcomes these limitations. A current drawback of SERS is the lack of available tools to analyze the bioconjugation of antibodies to nanoparticles following EDC/sulfo-NHS cross-linking, which produces inconsistent results and determines the efficacy of SERS probe targeting. This study uses the flow cytometry approach to evaluate SERS particles by incorporating FITC and DyLight650 secondary antibodies. Flow cytometry was also used to assess targeting of particles to markers on LY10 cells and CLL cells and to detect SERS signals by inserting a 710 BP 10nm FWHM filter specific for MGITC.
|
265 |
Product Differentiation and Consumer Preferences for Sustainable Food / Product Differentiation and Consumer Preferences for Sustainable Foodvon Meyer-Höfer, Marie 15 May 2014 (has links)
No description available.
|
266 |
Marketing Sustainability in Charter Tourism : The Influence of Brands, Eco-Labels and their Combination on the Swedish Charter Tourist´s Decision MakingReje, Anders, Dreger, Elena January 2014 (has links)
Tourism as one of the biggest industries in the world has been changing continuously and rapidly. The publishing of the Brundtland Report in 1987 has accelerated the discussion about combining economic, social and environmental factors – the so-called triple-bottom line – in order to secure long-term sustainable living conditions on a finite planet for both business and society. This has lead to occurring pressure from different stakeholder groups as for example policy makers or non-governmental organizations (NGO’s) urging for more sustainable business practise within the industry whereas one important pressure group appears to be missing out in this context: the customers of mass tourism products and therefore the demand side within the economic equation. Tourists have been observed to be overall reluctant to pay price premiums for more sustainable travel alternatives and seem to “take vacation” from their everyday green behaviour. Hence at the current point of time eco-tourism appears to be a market niche in which mainly small-scale providers and NGO’s like Nature’s Best in Sweden operate. However integrating mass tourism into the consideration can be seen as a promising opportunity and from an environmental standpoint an urgent necessity as it can be argued that within an industry of this scale, even small improvements towards more sustainable behaviour bear the potential for a substantial impact. The purpose of this study therefore lies in researching the two marketing tools of brands and eco-labels and the influence they can have individually and in combination on the tourist’s decision making delimitated to the context of charter tourism in Sweden. Through the research of this study it was found that currently no directly applicable theory about the combination of brands and eco-labels seems to exist for marketing neither in general, nor for the tourism industry in particular. This strongly indicates the novelty of the topic of combining brands and eco-labels and points out research opportunities. In order to achieve this purpose, a mixed-method research design was used combining qualitative expert interviews from direct business representatives and a quantitative data collection utilizing the scholarly acknowledged marketing research method of conjoint analysis in one of its most up-to-date forms of an adaptive choice-based conjoint analysis. Theory from different fields of study as consumer behaviour and decision making, branding and eco-labelling as well as sustainability marketing was combined and translated into the new and emerging service category of sustainable tourism. From this a conceptual framework was developed combining the data collection results from the mixed-method approach. This leads to the identification of ways for improving current charter tourism companies’ marketing based on the customers’ current view on utilities within certain aspects of the tourism package. Overall this study therefore contributes to the discussion on how demand for sustainable products evolves and can likely be increased. This is seen as a valuable theoretical, practical and societal contribution as it helps improving tourism companies’ understanding of their customer base and supports offering products/services with an improved perceived individual and societal value for charter tourism companies that aim for a higher degree of sustainability in their objectives.
|
267 |
Consumers' preferences for private and national brand food products / L. WymaWyma, Louise January 2010 (has links)
Introduction: The importance of brands and the competition between private and national brands in different food categories increased in recent years. According to literature, except for packaging and price, there is virtually no difference between the contents of food products in the majority of private and national brands. Private brands are usually cheaper than national brands. Previous research indicated consumers’ preferences for private and national brand food products to differ between various products and in different regions. Objective: The aim of this study was thus to determine the relationship between consumers’ brand preferences for different food products, in relation to their demographics and psychographics in a South African context. Setting: A mall intercept, interviewer administered questionnaire was used as a quantitative method in this study in Potchefstroom in a South African context. Consumers’ preferences for private and national brand food products in different product categories were explored, using preference, psychographics and demographical questions simultaneously. Results: Respondents in this study preferred to purchase national brands in all products categories except for cooking oil. Considering eight psychographic factors that were extracted by exploratory factor analysis, two factors could be associated with positive reactions, while neutral reactions were evident for six factors. Respondents being indecisive on the majority of factors could be due to the fact that national brands were preferred for most products by respondents in the present study. Conclusions: Although brand preference depended on demographics and psychographics in previous research, the present study did not find significant relationships with psychographics when different products were used. Although a combination of demographic factors (mainly gender, education level, home language and employment status) could be useful in determining brand preference when used with specific products, home language and education level seem to be the most important factors. Therefore, brand preference depended on specific demographics for each product, while psychographic factors did not play a significant role. This implied that brand preference research should be product and region specific using specific demographic variables. / Thesis (M. Consumer Science)--North-West University, Potchefstroom Campus, 2011.
|
268 |
Consumers' preferences for private and national brand food products / L. WymaWyma, Louise January 2010 (has links)
Introduction: The importance of brands and the competition between private and national brands in different food categories increased in recent years. According to literature, except for packaging and price, there is virtually no difference between the contents of food products in the majority of private and national brands. Private brands are usually cheaper than national brands. Previous research indicated consumers’ preferences for private and national brand food products to differ between various products and in different regions. Objective: The aim of this study was thus to determine the relationship between consumers’ brand preferences for different food products, in relation to their demographics and psychographics in a South African context. Setting: A mall intercept, interviewer administered questionnaire was used as a quantitative method in this study in Potchefstroom in a South African context. Consumers’ preferences for private and national brand food products in different product categories were explored, using preference, psychographics and demographical questions simultaneously. Results: Respondents in this study preferred to purchase national brands in all products categories except for cooking oil. Considering eight psychographic factors that were extracted by exploratory factor analysis, two factors could be associated with positive reactions, while neutral reactions were evident for six factors. Respondents being indecisive on the majority of factors could be due to the fact that national brands were preferred for most products by respondents in the present study. Conclusions: Although brand preference depended on demographics and psychographics in previous research, the present study did not find significant relationships with psychographics when different products were used. Although a combination of demographic factors (mainly gender, education level, home language and employment status) could be useful in determining brand preference when used with specific products, home language and education level seem to be the most important factors. Therefore, brand preference depended on specific demographics for each product, while psychographic factors did not play a significant role. This implied that brand preference research should be product and region specific using specific demographic variables. / Thesis (M. Consumer Science)--North-West University, Potchefstroom Campus, 2011.
|
269 |
Vartotojų požiūris į ekologiškus maisto produktus ir jo sąsajos su subjektyviu sveikatos vertinimu / Consumers' attitude towards organic food and it's relation with subjective health estimationGintautaitė, Lina 18 June 2014 (has links)
Darbo tikslas. Įvertinti vartotojų požiūrį į ekologiškus maisto produktus ir nustatyti sąsajas su subjektyviu sveikatos vertinimu.
Tyrimo metodika. Anketinės apklausos metu buvo siekiama išsiaiškinti Kauno miesto suaugusių vartotojų požiūrį į ekologiškus maisto produktus, įvertinti vartotojų informuotumą apie ekologiškų maisto produktų ženklinimą, išsiaiškinti kriterijus pagal kuriuos vartotojai renkasi ekologiškus maisto produktus. Tyrimo metu buvo išdalinta 317 anketų, iš kurių pilnai ir tinkamai užpildytos sugrįžo 263 anketos (atsako dažnis 82,96 proc.) Apklausoje dalyvavo – 84 vyrai ir 179 moterys. Kokybinių požymių statistinis ryšys vertintas remiantis chi kvadrato (χ2) bei z kriterijais. Siekiant įvertinti vartotojų informuotumo apie ekologiškų maisto produktų ženklinimą lygį bei ekologiškų maisto produktų vartojimo sąsajas su subjektyviu sveikatos vertinimu buvo skaičiuotas šansų (galimybių) santykis. Rezultatų skirtumas laikytas statistiškai reikšmingu, kai paklaidos tikimybė (p) <0,05.
Rezultatai. 67,5 proc. respondentų teigė, kad vartoja ekologiškus maisto produktus, iš jų daugiau moterų nei vyrų. 2-3 kartus per savaitę ekologiškus produktus teigė, kad vartojo 39,2 proc. moterų ir 37,0 proc. vyrų. Įvertinus sąsajas tarp subjektyvaus respondentų vertinimo apie ekologiškų maisto produktų ženklinimą Lietuvoje ir tikrojo žinių įvertinimo pagal atpažintus logotipus, paaiškėjo, kad tarp teigusių, kad žino kaip yra ženklinami ekologiški maisto produktai, iš tikrųjų žino... [toliau žr. visą tekstą] / Aim of the study. To evaluate consumers attitude towards organic food and its relation with subjective health estimation.
Methods. The study included anonymous questionnaire for adult consumers in Kaunas city to investigate the attitude towards organic food, to evaluate the knowledge of organic food labelling and the motives of the consumers in purchasing organic food. During the study 317 questionnaires were given to the consumers and 263 returned properly fulfilled (response rate 82.96%). 84 men and 179 women participated in the study. Qualitative statistical relations of the variables were analysed by using Chi-squared and z criteria. The knowledge level of the organic food labelling and the associations between organic food consumption and the subjective health estimation were valued by odds ratio. The statistically significant difference were identified when (p)<0.05.
Results. 67,5% of all respondents, the bigger proportion of women than men of the study, stated consuming organic food. Organic food was consumed mostly 2-3 times per week by 39.2% of women and 37.0% of men. The results showed that comparing subjective knowledge of the organic food labelling in Lithuania and the knowledge by practically identified labels by the respondents, the respondents who told that they know the organic food labelling, really know only 15.5% of respondents and previously existing labelling know 34.5%; responders who told that they know the labelling of organic food but really they do... [to full text]
|
270 |
Barriers & Facilitators to Overcoming Obesity in Canada and the Role of Fat-related Nutrient Content ClaimsSchermel, Alyssa 27 June 2013 (has links)
Our overall objective was to explore some individual and environmental determinants of eating habits with a main focus on nutrition labels and their usefulness for choosing foods for weight management. We first broadly examined these determinants using participants of the AFMNet Canadian Consumer Monitor (CCM), and found a number of attitudinal and perceived environmental barriers to healthy eating. In an experimental study with CCM respondents, we found that reduced fat claims may help consumers make better choices for weight management if calorie content on the Nutrition Facts Table is also considered. However, in our examination of foods with fat claims in the Canadian marketplace, we found that most products with fat claims are not significantly lower in calories than comparable foods without such claims. We conclude that fat claims could be useful in assisting consumers with food choices for weight management, if the foods were also reduced in calories.
|
Page generated in 0.0631 seconds