Diabetes mellitus is a bihormonal disorder with hyperglycemia due to deficiency of insulin and hypersecretion of glucagon. To improve diabetes treatment it is important to clarify the signal transduction of glucagon secretion. The cytoplasmic Ca2+ concentration ([Ca2+]i), an important determinant of hormone secretion, and the membrane potential were recorded in individual mouse α-cells. Glucagon and insulin secretion were measured from mouse islets and glucagon secretion from hamster glucagonoma cells. Glucose inhibited glucagon secretion from islets and glucagonoma cells with maximal effect at 7 mM, indicating a direct action on the α-cells. High concentrations of glucose paradoxically stimulated glucagon secretion. Whereas glucose inhibition of glucagon release was associated with lowering of [Ca2+]i, stimulation of secretion at high glucose concentrations was Ca2+-independent. Adrenaline, which is a potent stimulator of glucagon secretion, increased [Ca2+]i by α1- and β-adrenergic mechanisms involving mobilization of intracellular Ca2+ from the endoplasmic reticulum (ER) and influx of the ion across the plasma membrane. Ca2+ mobilization could be attributed to generation of inositol 1,4,5-trisphosphate and cAMP, and influx occurred through voltage-dependent L-type channels activated by a depolarizing store-operated current. Glucose hyperpolarized the α-cells and inhibited adrenaline-induced [Ca2+]i signalling. At 3 mM, glucose had a pronounced stimulatory effect on Ca2+ sequestration in the ER, shutting off store-operated Ca2+ influx. The α-cells express ATP-regulated K+ channels but pharmacological blockade of these channels neither interfered with the hyperpolarizing and [Ca2+]i lowering effects of glucose nor with the inhibition of glucagon secretion. In contrast, activation of the depolarizing store-operated mechanism prevented glucose-induced, hyperpolarization, lowering of [Ca2+]i and inhibition of glucagon secretion. It is proposed that adrenaline stimulation and glucose inhibition of glucagon release involve modulation of a store-operated depolarizing current. The U-shaped dose response relationship for glucose-regulated glucagon secretion may explain the hyperglucagonemia in diabetes.

This research investigates ways to help shoppers evaluate physical products via the Internet. The primary research issue is, therefore, how to provide experience vicariously. The study was undertaken in three parts. First, an extensive range of Web sites belonging to Internet-based retailers was examined, together with literature on vicarious experience and Web page design. These helped to explore the question of ‘What components of Web-based representations of physical products might assist shoppers when trying to evaluate those products as part of a purchase decision?’ Online store systems that are representative of the main communication styles found in the Web survey were then evaluated in a series of laboratory-based experiments. This second part of the study makes a broad assessment of the impact of representative technologies on the product evaluation process. Finally, a smaller-scale, more targeted investigation was conducted, also using a laboratory-based experiment. This third part of the study assesses the impact of an individual’s evaluation style on the perceived success of representative technologies.

Thesis (M.Arch.) - Carleton University, 2005. / Includes bibliographical references (p. 111-113). Also available in electronic format on the Internet.

Thesis (M.A.) - Carleton University, 2006. / Includes bibliographical references (p. 146-153). Also available in electronic format on the Internet.

Dissertation (PhD)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.

Thesis (MA)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.

The objective of this study is to conduct a marketing mix modeling to measure the effectiveness of past marketing activities on the product sales using a time-varying effect model (TVEM) approach. The longitudinal intensive data for this study has come from a large ice cream manufacturer in USA. Traditionally, static regression models have been used to measure the effectiveness of marketing mix variables to predict sales. And, these models used to find the time independent effect of the covariate on the dependent variable. On the other hand, a dynamic model such as time-varying effect model takes time into consideration. Researchers can model the changes in the relationship between dependent and independent variables over time using time-varying effect model. This is the first study, where a time-varying effect model approach has been used to measure the effectiveness of marketing mix elements in the ice cream industry. In addition, we have compared the predictive validity of both static and dynamic models using this data set.

Since internet was born digitalization has flourished and led to technological innovations that opened up new opportunities on the market. In the retail sector, the digitalization and development of mobile devices, tablets and social media have changed the traditional trade both online and in physical stores. In order to cope with the challenge of digitalization and to meet consumers' new expectations, more companies have begun offering customers a seamless customer experience between physical and digital stores, called omnichannel. Omnichannel represents a very favorable opportunity for companies to exploit synergies between channels to synchronize interactions with consumers across multiple channels. The purpose of this paper is to investigate perceptions of the link between omnichannel strategy and consumers trust. Since the purpose of the study is to increase understanding of perceptions about the connection between omnichannel strategy and consumer trust, we have chosen a qualitative research method. Our empirical evidence was collected through six interviews with experts in the field of omnichannel and people that have experience of omnichannel as a strategy. The result shows that respondents perceive that companies can use different channels to create trust, but different channels have different conditions. For example, it is harder to build trust through digital channels if they are not linked to a physical store. Omnichannel can therefore create synergies in which the company can benefit from each channel's trust-making features. However, respondents perceive that omnichannel is very difficult to organize and can create major problems for companies unable to handle this integration of the channels.

Background: Due to accelerating environmental problems caused by fast fashion sustainable business solutions become increasingly important. Thus, the following thesis examines generation y’s intention to perform in-store recycling at fast fashion retailers and investigates the factors most influential on intention. Besides, it analyses if an attitude-intention gap exists. To fulfil the study’s purpose, a combination of the theory of planned behaviour (Ajzen, 1985) and the norm activation model (Schwartz, 1977) is used.   Approach: Within this study a quantitative method in terms of an online survey is applied. Based on a sample of 326 respondents, relationships between variables are analysed with Pearson correlation analysis and multiple regression. To further identify differences among groups, Independent samples t-test and ANOVA are conducted.     Findings: The study’s findings reveal that generation y generally intends to participate in in-store recycling, while the intention is significantly higher among women than men. The intention to perform in-store recycling is predominantly intrinsically motivated as it is most driven by individuals’ personal norm.    Value: The findings of our study particularly add value for fast fashion retailers and marketers by presenting a novel research model combining most relevant factors required to adequately address consumers among generation y to perform in-store recycling. This specifically allows fashion retailers to successfully establish the concept of in-store recycling. Our study is further beneficial for sustainability researchers, environmental activists, charity organisations and policy makers to create a more sustainable future.

The aim of this thesis was to analyze the use of multichannel retailing in Globus hypermarket in České Budějovice. Dispensation was done according to Levy and Weitz (2009) into three main channels {--} retail store, catalogue and the internet which were supplemented by some components of the communication mix. On the basis of the case studies and marketing situation analysis of Globus hypermarket in České Budějovice some measures were proposed to improve the competitive position of this company by the use of multichannel retailing. Partial proposals were devided by particular channels. One of them was also economically evaluate.