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En esta tesis se estudiaron varios sistemas de anfifilos mezclados que involucran moléculas de estructura no tradicional, como lo son las sales biliares,ácidos biliares y análogos. Sus divergencias estructurales con los surgactantes convencionales hace que presenten un comportamiento de agregación atípico que es mucho más acentuado en sistemas mezclados. El estudio se dividió en cuatro partes principales: (a) comportamiento de agregación en solución acuosa, (b) comportamiento de la interfase aire-solución en monocapas extendidas o de Langmuir y (d) síntesis de materiales nanoestructurados bioactivos de SiO2. Tanto el comportamiento de agregación en solución como el inerfacial reveló que las mezclas de la sal biliar deoxicolato de sodio (NaDC), el derivado artificial dehidrocolato de sodio (NaDHC) y el surfactante catiónico de dos colas bromuro de dimetildidodecilamonio (DDAB) son no ideales en todas las proporciones. Los estudios se realizaron de a pares NaDC-NaDHC, NaDHC-DDAB y NaDC-DDAB; asimismo se evaluó la presencia de agregados pre-micelares del tipo jabón ácido. Se pudo determinar que las soluciones acuosas de las mezclas de NaDC-NaDHC están constituidas por micelas esféricas, mientras que para el sistema NaDHC-DDAB se encontró un proceso de agregación en dos pasos, en un primer paso se forman micelas y en un segundo vesículas multilaminares con diámetros entre 200 y 600 mm, siendo esto últimos dependientes de la composición de la mezcla. El sistema NaDC-DDAB, sin embargo, presentó solo vesículas unilamelares de 1-2 mm de diámetro. Estas diferencias se deberían a la perturbación estérica que causa la intercalación del esqueleto colestérico en los agregados mezclados, lo cual se confirmó al evaluar su comportamiento interfacial. Aquellos sistemas que dieron lugr a agregados de estructuras novedosas se empleatron como moldes para obtener materiales porosos de siliciol. Se obtuvieron materiales tipo esponja que resultaron tener una organización similar al hueso trabecular. La estructura final de los materiales proviene de una transición de fases de vesícula a una fase bicontínua tipo esponja, la fuerza directriz de la transformación sería la interacción de las sales biliares y el DDAB con los precursores de silicio (tetraetlortosilicato de sodio, TEOS) durante la etapa de polimerización en la síntesis del material. Dependiendo del tipo y cantidad de sal biliar enla mezcla plantilla, la curvatura de los agregados se puede dar hacia el lado polar o apolar, llevando a morfologías finales diferentes. El esqueleto esteroidal altamente hidrofóbico de la molécula de NaDHC causa una gran perturbación en la mezcla usada como plantilla y solo las mezclas con aNaDHD = 0,2 y 0,4 produjeron materiales conuna estructura definida (aNaDHC: fracción molar de NaDHC en la muestra sin tomar en cuenta el solvente). Bajo ciertas condiciones de síntesis específicas, los materiales presentatron un comportamiento bioactivo. Este último se determinó por la capacidad del material de desarrollar sobre su superficie una cubierta de hidroxiapatita similar a la ósea en contacto con fluidos fisiológico simulado. Suponemos que sus propiedades están relacionads con los mesoporos y alta proporción de puentes siloxanos en sus estructuras. / This thesis studies various mixed systems inolving non-traditional structure amphiphilic molecuels, sucha as bile salts, bile acids and analogs. Their structural differences with conventional surfactnts causes an atypical aggregation behavior that is much more pronounced in mixed systems. The study was divided into three main parts: (a) aggregation behavior in aqueours solution, (b) behavior of adsorrbed monolayers (or GHibbs monolayers) at the air-solution interface, (c) behavior of spread monolayers (orLangmuir monolayers) at the air-solution inferfaceand (d) synthesis of bioactive SiO2 nanosturctured materials. The aggregation behavior in solution and at the air-solution interface revealed that mixing of bile salt sodium deoxycholate (NaDC), the artificial sodium dehydrocholate derivative (NaDHC) and the two-tailed cationic surfactant dimethyldidodecylamonium brinude (DDAB), is non-ideal in all proportions. Studies were perfomed by pairs: NaDC-NaDHC, NaDHC-DDAB and NADC-DDAB. The presence of acid soap-like premicellar aggregates was also evaluated. It was found that aqueous solutions of mixtures of NADC-NaDHC consist of sphericalmicelles, while for the mixed system NaDHC-DDAB aggregation occurs in two steps. In a first step miclles form and then grow in a second sept to multilamellar vesicles with sizes between 200 and 600 mm, varying the composition of the mixture . However, the NaDC-DDAB mixed system showed only unilamellar vesicles, about 1-2mm diameter. These differences are due to steric disturbance caused by intercalation of cholesteric skeketon in mixed aggregates; this was confirmed by evaluating interfacial behavior. Those stystems which gave aggregates with novel structures were used as templates to obtain porous silicon materials. Sponge-like materials were obtained, which have been proven to have a similar organization to the trabecular bone. The final structure of the materials comes from a phase trnsition from vesicles to a sponge-like phase. The driving force of the process would be the interaction between bile salts and DDAB with silicon precursor (sodium tetraethylorthosilicate, TEOS) during polymerization step in thesynthesis of the material. Depending on the type and amount of bile salt in the template mixture, the curvature of the aggregates can be to the polar or a-polar side, leading to different final morphologies. The highly hydrophobic NaDHC steroid skeleton causes a great disturbance in the mixture used as a template and only mixtures with aNaDHC= 0.2 and 0.4 produced materials with a defined structure. Under certain specific synthesis conditions, te materials exhibited bioactive behavior. Bioactivity was determined by the material capacity of developing a hydroxylapatite coating on its surface, similar to the bone, in contact with simulated physiological fluids. We suppose that their properties are related to the high proportion of mesopores and siloxane bridges in their structure.

Objective: The aim of this study was to develop and evaluate a 12-week multi-faceted, child-focused intervention that included a point-of-purchase kiosk featuring fresh fruits, vegetables, and healthy grab-and-go snacks; and a sampling pod, comprised of food items from the kiosk. Design: An observational uninterrupted time-series design was used in one intervention grocery store. The intervention consisted of two components, a Healthy Kids Kiosk and food sampling. Subjects/Setting: Patrons of Ukrop's Inc. Grocery store in Roanoke, Virginia. May-September 2009 Measures: The study measures consist of three components: 1) examination of changes in sales data for featured products, provided by the grocery chain; 2) candid, unobtrusive, blind observations of customers near and around the intervention; and 3) brief questionnaires of customers, who engaged at some level with the Kiosk and sampling pod. Results: The results yielded an overall increase in the proportion of the sales of the featured items to total store sales during the intervention period. Individual items that increased sales during the intervention period, included whole-wheat mini bagels, bananas, radishes, honey, sunflower, baked tortilla chips, and almond butter (p<.05). Parents whose children were arguing, crying/whining, or not in the shopping cart, had higher levels of engagement with the kiosk. Almost two-thirds (61.7%) of the patrons interviewed noticed the healthy kids kiosk, with about one-quarter (28.7%) indicating that they purchased at least one item. Fifty-eight percent reported that the kiosk encouraged them to buy healthier foods. Conclusion: Promoting healthy foods at point-of purchase locations can result in increased purchases of these foods among families with young children. Application: These findings have provided insight into the effectiveness of grocery store interventions on purchasing patterns and behaviors of families with young children. / Master of Science

Yes / Purpose - Although recent literature has examined diverse measures adopted by SMEs to navigate the COVID-19 turbulence, there is a shortage of evidence on how crisis-time strategy creation behaviour and digitalization activities increase (1) sales and (2) cash flow. Thus, predicated on novel strategy creation perspective, this inquiry investigates the crisis behaviour, sales and cash flow performance of 528 SMEs in Morocco. Design/Methodology/Approach - Novel links between (1) aggregate wage cuts, (2) variable operating hours, (3) deferred payment to suppliers, (4) deferred payment to tax authorities and (5) sales performance are developed and tested. A further link between sales performance and cash flow is also examined and the analysis is performed using a non-linear structural equation modelling technique. Findings - While there is a significant association between the strategy creation behaviours and sales performance, only variable operating hours have a positive effect. Also, sales performance increases cash flow and this relationship is substantially strengthened by e-commerce digitalization and innovation. Originality/Value – Theoretically, this is one of the first inquiries to espouse the strategy creation view to explain SMEs’ crisis-time behaviour and digitalization. For practical use, to supplement Moroccan SMEs’ propensity to seek tax deferrals, it is argued that debt and equity support measures are also needed to boost sales performance and cash flow.

The purpose of the survey was to study the business organizations from the standpoint of type, number of office employees, and the type and number of office machines used, in order that the commercial courses of the Kingsville High School could be patterned to these business needs.

This study offers insight into the perceived leadership behaviour of sales managers in a pharmaceutical organisation in South Africa. The study specifically investigated the extent of the relationship between leadership behaviour of sales managers and motivation of sales teams during the implementation of strategic alliances. The study followed a mixed methods approach and had a correlational research design. The population in this study was the fifty four (54) sales representatives and their respective sales managers of the six sales teams identified, who are directly responsible for implementing strategic alliances. The population was demarcated into six (6) sales teams with each team reporting to a separate sales manager. Inferential and descriptive statistics were used to analyse the data. The quantitative data were analysed using Pearson’s correlation coefficient (r). The qualitative component was analysed using a content analysis. The findings of the correlation analysis suggest that an overall positive and moderate relationship exist between autocratic leadership behaviour of sales managers and the motivation of sales teams. A similar relationship exists between team leadership and extrinsic motivation. A positive and weak relationship exists between directive and supportive leadership and motivation. Similarly, a positive and weak relationship exists between team leadership and intrinsic motivation. However, the extent to which these relationships exist varies between the sales teams. The findings of the content analysis indicate that task-oriented leadership behaviour may exert the strongest motivator for sales teams when implementing strategic alliances. / Business Management / M. Com. (Business Management)