Dissertations / Theses on the topic 'Ant colony social behaviour'

The organization of complex societies requires constant information to flow between individuals. Because of their elaborated social structures and principally because of the division of labor, social insects depend on the efficacy of their information web in order to adapt the colony activity to its needs. Although many studies focused on understanding the regulation of the foraging activity, little is known about the intranidal food distribution and stock management regulation. The aim of this thesis is to quantify and describe the dynamics of the food flow and its regulation in an ant colony. A medical imagery technique, scintigraphy, was adapted to follow the propagation of radio-labeled nutrients inside the nest. This technique allowed spatiotemporal dynamics quantification of the food flow and led to the enunciation of simple yet robust regulation rules that are at work during the colony feeding process.

The dynamics of the harvest is regulated by the coupling of a positive and negative feedbacks. The harvest acts as both: negative and positive feedbacks. Entering food-loads trigger foragers to exploit the newly discovered food source through the well-known recruitment process. At the same time, the harvest proportionally reduces the entering food flow until the complete stop of the foraging activity when the colony reaches satiety. Surprisingly, the positive feedback (that is the recruitment) is not responsible for a faster entering food flow and is not influenced by the colony needs while the exploring activity is. The spatial dynamics of the food exchange network revealed stable patterns and fine tuning regulation of the feeding process. Spatial analysis of the food distribution showed that sucrose is heterogeneously stored among individuals and also heterogeneously consumed. We observed a regular spatial structure leading to centralization of the stocks: heavy loaded individuals being at the center of the cluster and weakly loaded individuals at its periphery.

The spatiotemporal quantification of the food flow allowed describing and understanding the flexibility of the colony to adapt its working force according to its nutritional requirements.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

Betweenness centrality refers to the measure of a node’s influence on the transfer of items within a network. It is a mechanism used to identify participants within an interconnected system that are responsible for processing high frequencies of traffic. This thesis examines the performance characteristics of a specialized artificial intelligence algorithm known as Ant Colony Optimization and its application in the field of social network analysis. The modeling and examination of such algorithms is important largely because of its ability to span across multiple fields of study as well as a variety of network applications. The effects of network analysis can be felt everywhere. Business and military intelligence; hardware resiliency (fault tolerance); network routing, are but a few of the fields that can and do benefit from research due in part to specialized network analysis. In this research paper, extensive social networks are built, execution time is measured, and algorithm viability is tested through the identification of high frequency nodes within real social networks.

The determination of a symbiotic association as beneficial requires good assessment of the costs and benefits involved in the maintenance and transmission of these microbes across generations. In social insects, symbiotic associations are complex as they may involve a network of interactions between individual and colony that result in stable associations over evolutionary time. My goal was to investigate the roles of behavior and morphology as integrators that have enabled the benefits of harboring gut microbes to reach both adult and growing brood in a colony. To achieve this goal, I used turtle ants (Cephalotes), a group that has co-evolved with their gut microbes since the Eocene (Sanders et al. 2014) and that shows a variety of morphological and behavioral specializations likely connected to this symbiotic association. In my dissertation I present evidence that the specialized behavior and morphology of Cephalotes are indeed strongly associated with mechanisms that ensure stability of ant-gut microbe interactions over evolutionary time. In Appendix A, I show that a valve between the crop and midgut (proventriculus) of C. rohweri works as a filtration organ, capable of excluding possible pathogens from the mostly liquid diet consumed by turtle ants. In addition, the proventricular filter is also associated with the structuring of the gut microbiota, dividing it in at least two great groups: one upstream and another downstream of the proventriculus. Through behavioral observation and microscopy, we also suggest that the formation of the proventricular filter is only complete after young and sterile workers (callows) are inoculated with the core group of symbiotic bacteria. In Appendix B, I present results confirming that the compartmentalization of gut microbiota is also present in the congener C. varians. I compare these results with previously published data, defining the meta-communities of the gut microbiota, and demonstrate that the previously recognized core microbiota is composed of compartment-specific microbial communities and lineages. This compartmentalization of the gut microbiota is similar to the one found in highly specialized herbivores, both vertebrates and invertebrates. In addition, I also sampled the infrabuccal pocket, a characteristic oral cavity found in ants and that has largely been ignored in studies of gut symbiosis. Based on my results, I provide compelling evidence that hindgut microbes are inoculated into food particles trapped in the infrabuccal pocket, aiding in digestion of this substrate. Moreover, I suggest that trophallaxis olays a central role in inoculation of food and individuals, and might be responsible for the transmission of nutrients that are predicted to result from the gut bacteria metabolism. Finally, in Appendix C I characterize abdominal trophallaxis in C. rohweri to gain insight on its role in the context of symbiotic associations with gut microbes. I show that the hindgut contents, including bacteria, can be transmitted via abdominal trophallaxis. This interaction is found to occur between all combinations of major and minor workers, in addition to callows. The rate of solicitation of abdominal trophallaxis is higher when individuals are protein starved, indicating that hindgut content may also be nutritive. Using shotgun metagenomic data, we show that the microbiota present in the infrabuccal pocket (mostly hindgut bacteria) are indeed capable of re-utilizing nitrogen and synthesizing essential amino acids, in addition to breaking down plant material. We also report that oral trophallaxis is a possible route for transmission of crop-specific bacteria for callows, as this group has performed oral trophallaxis at a relatively higher rate than older workers. Put together, these results highlight the importance of nestmate interactions and gut morphology in the establishment and maintenance of symbiotic microbes in a social insect, introducing a new model for explaining the evolution and functioning of ant-gut microbe symbiosis.

Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xv, 271 p.; also includes graphics (some col.) Includes bibliographical references (p. 252-265). Available online via OhioLINK's ETD Center

Aspects of the behaviour of the wood ant Formica aquilonia were studied using semi-natural conditions in the laboratory and under natural conditions in Loch Ard Forest, Aberfoyle, Scotland. In this study the main effort was towards an understanding how the foraging population is structured and controlled. As the preferred food site of the foragers is often the first located site: maximisation of the net energetic yield of the colony as a whole may conflict with the optimal foraging as measured at the individual level. Site allegiance is a constant property of certain individuals within the colony's foraging population. A key component of the foraging system is a mechanism whereby a colony keeps a large proportion of its forager force distributed on the most profitable food sites whilst it members show strong site allegiance. Wood ants discriminate food sources without making comparisons among honeydew sources. Naive foragers show transient behaviours in their foraging repertory more often that veteran, allegiant foragers. This behaviourally flexibility of naive foragers is used to trace novel food sties likely to occur in the habitat. It is represented in this study by the small number of foragers recruited daily. By this recruiting of uncommitted foragers to the foraging population F. aquilonia colonies are able to overcome inherent inertia associated with site allegiance. Although significant differences may be observed at the foragers' level of activity, there are no sub populations operating at day and night time. The gradual declining activity observed when the colony was subjected to a 17.5:6.5 light:dark cycle does not begin immediately after the light out. The rhythmicity was poor in constant dark and complete arhythmicity in constant light suggesting that these rhythms are entrained by light:dark cycles. There was no evidence found to support that F. aquilonia foragers depend on chemical cues to orient to carbohydrate food sources: mainly honeydew provided by aphids.

Social insects are used as models for understanding the evolution of sociality because they show seemingly complex behavioral and physiological traits that enforce group cohesion, collective organization, and group level reproduction. Social organization in insect societies requires workers to share information. Information sharing allows workers to efficiently perform and switch among tasks to meet colony needs. For many species that nest in preformed cavities, colony growth results in crowding inside the nest which can affect colony productivity and fitness. How does colony size and social density affect individual and collective behavior? Using a combination of laboratory and field experiments, I have begun to answer this question. In Temnothorax rugatulus ants, high social density resulted in greater colony energy use. In addition, larger colonies used proportionally less energy compared to smaller colonies, but showed reduced brood production. These results indicate that the way colonies use energy changes with social density and group size. In analyzing the effects of colony size and density on worker behavior, I found that high density increased worker connectivity and information sharing. Workers in larger colonies showed less connectivity compared to workers in smaller colonies. Interestingly, workers with more interactions spent less time in brood care. This study shows that workers' access to information and the overall pattern of information flow are affected by social density and colony size, and changes in worker connectivity can influence task behavior. The next study shows that field colonies maintained a relatively constant level of intranidal density irrespective of colony size; this suggests that Temnothorax ants actively regulate social density. When colonies were established in high density nests, they showed greater foraging and scouting activities, and this led to a higher probability for becoming polydomous, i.e., occupying multiple nests. When polydomy occurred, colonies divided evenly between two nests, but distributed fewer, heavier workers and brood to the supplemental nests. Taken together, the first four studies indicate that social density is an important colony phenotype that affects individual and collective behavior and energetics in ants, and the collective management of social density may be a group adaptation in ants and other social insects. Lastly, because crowding affects polydomy behavior, the final two experiments tested whether colony emigration and nest construction and dispersion, two strategies for reducing intranidal crowding, are influenced by food distribution. Temnothorax colonies preferred to emigrate to nests positioned closer to food, and weaver ants (Oecophylla smaragdina) positioned newly constructed nests in food-rich areas. Furthermore, weaver ants used the newly constructed nests to more rapidly retrieve and safeguard valuable food items. Thus, strategic emigrations and adaptive nest dispersion can remedy intranidal crowding and at the same time allow growing colonies to acquire adequate food to meet colony needs.

This thesis shows that socially subordinate Arctic charr (Salvelinus alpinus) display elevated brain serotonergic (5-HT) and norepinephric activity along with a chronic activation of the hypothalamic-pituitary-interrenal (HPI) axis, including elevated plasma concentrations of á-MSH. Furthermore, subordinate fish showed an inhibition of aggressive behaviour and darker body coloration, skin darkness being positively correlated with plasma á-MSH. Fish kept on dark background, and thus being darker in body colour, were less aggressive than conspecifics interacting on white background, supporting the hypothesis that skin darkening could signal social submission. The 5-HT_1A -receptor agonist 8-OH-DPAT stimulated HPI axis activity in non-stressed fish, but if administrated to stressed fish it inhibited HPI axis activity, suggesting that 5-HT_1A receptors may act as both post- and pre-synaptic receptors. 8-OH-DPAT also induced skin darkening in both non-stressed and stressed fish. Stimulation of brain dopaminergic activity by L-dopa treatment counteracted the stress-induced inhibition of aggressive behaviour, and stress related effects on brain 5-HT activity and plasma levels of cortisol. In conclusion, social subordination in Arctic charr results in skin darkening and an inhibition of aggressive behaviour. Stress-induced effects, that could be mediated by elevated brain 5-HT activity, and serve as a way of signalling social position and coping with stress.

Particulièrement lors de collaborations dans le cadre de chaînes logistiques ou d'entreprises virtuelles, établir les workflows collaboratifs est une étape laborieuse car souvent réalisée soit de façon humaine, soit avec des méthodes manquant de flexibilité. Sur la base d'un réseau social d'entreprises, cette thèse vise à faciliter cette étape en proposant un service de déduction de processus collaboratifs inter-organisationnels. Cela soulève trois problèmes: (i) trouver les activités qui doivent être exécutées pour remplir les objectifs de la collaboration (Quoi?), (ii) sélectionner les partenaires pouvant réaliser ces activités (Qui?) et (iii) ordonner ces activités en un processus métier collaboratif (Quand?). Dans le cadre d'un réseau social, il est attendu que plusieurs organisations soient capables de fournir les mêmes activités. Dans un tel contexte de concurrence entre les organisations, une optimisation globale permet de trouver un processus final quasi-optimal, en prenant en compte ces trois questions de manière simultanée : trouver l'ensemble des "meilleurs" partenaires et leurs activités dans un contexte de collaboration spécifique. A cette fin, des ontologies de collaboration ont été développées et permettent de représenter et collecter des connaissances sur les collaborations. Ainsi, quand les utilisateurs remplissent leurs profils sur le réseau social, le système peut comprendre (i) les attentes des utilisateurs lorsqu'ils fournissent leurs objectifs de collaboration et (ii) les capacités qu'ils peuvent fournir. Un outil d'aide à la décision, basé sur un algorithme d'optimisation par colonies de fourmis permet ensuite d'exploiter les ontologies de collaboration afin de trouver un processus quasi-optimal répondant aux attentes et objectifs de la collaboration. Les résultats de cette thèse s'inscrivent au sein du projet FUI OpenPaaS dont le but est d'établir un nouveau réseau social d'entreprises visant à faciliter leurs collaborations intra et inter-organisationnelles
Especially in the context of collaborative supply chains and virtual enterprises, the step of designing the collaborative workflows remains laborious because either it is still carried out humanly or the methods lack of flexibility. Based on an enterprise social network, this thesis aims at facilitating this step by proposing a service for the deduction of collaborative processes. It raises three main issues: (i) finding the activities to execute that answer the objectives of the collaboration (What?), (ii) selecting the corresponding partners (Who?) and (iii) ordering the activities into a collaborative business process (When?). Moreover, it is expected that many companies could be able to provide the same activities, on the enterprise social network. In this competitive context, a global optimization should be set up in order to find the quasi-optimal collaborative process that answer these three questions simultaneously. A three-dimensional solution is proposed here. First, a non-functional framework has been set up in order to determine the criteria that make a « good » partner in a specific collaborative context. Then, collaborative ontologies have been implemented and enable the representation and the acquisition of collaborative knowledge, so that the IT system can understand (a) the user's needs when they model their objectives of collaboration and (b) the user's capabilities when they model their profiles on the enterprise social network. And finally, a tool for decision support has been implemented thanks to an ant colony optimization algorithm that exploits the collaborative ontologies in order to provide a quasi-optimal process that fits the context of the collaboration and answers its objective. The results are in line with the FUI French project OpenPaaS which aims at offering an enterprise social network to facilitate their collaborations

Effective conflict management in the workplace can reduce the negative consequences of conflict. These negative outcomes can include low productivity, health-related stress, increased employee turnover, or litigation. A Human Resource (HR) professional can help mitigate these negative outcomes in the workplace when using effective conflict management behavior with employees. However, there is a void in research pertaining to HR professionals’ use of conflict management behavior. This quantitative, correlational research study examined whether personality has an impact on assertive or cooperative conflict management behavior of HR professionals in the workplace. Statistical testing found a significant relationship between the harmonious, people-person (a Blue personality in the True Colors personality model) and the assertive conflict management behavior. Another finding of this study sheds light on the need for conflict resolution (CR) education and training in the HR field. The majority of HR professionals in this study said “yes” to wanting and needing training and education in the CR skillset. This skillset includes many of the same specific strategies that are used by mediators (reflective listening, reframing, building rapport, step-by-step problem-solving, etc.). These skills would also enable HR professionals to manage and resolve interpersonal employee conflict before it escalates and leads to negative outcomes.

Entre 1960 et 1975, à la faveur du processus de décolonisation, deux pays indépendants et un territoire resté français succèdent à l’ancienne colonie de Madagascar. La question de l’évolution des systèmes archivistiques dans cette zone, de leur éventuelle diversification et de leur actuel degré de maturité, est posée dans ce contexte. À Madagascar, aux Comores comme à Mayotte, de louables intentions en faveur des archives peinent à se concrétiser, notamment faute de crédits et de stabilité politique. Les appareils archivistiques échouent à préserver toutes les archives et la collecte porte principalement sur le central au détriment du local. Un public existe mais il demeure majoritairement composé de personnels administratifs et de particuliers dont le besoin documentaire se borne souvent à la consultation du Journal officiel. La réussite d’autres types de recherches se heurte à l’éparpillement des fonds et au manque d’outils de recherche. L’observation des logiques d’usage confirme la surreprésentation des usages administratifs, la faiblesse de la sollicitation généalogique et l’existence de stratégies de contournements des organismes de conservation officiels. À côté d’eux ou hors d’eux, des initiatives privées de sauvegarde et valorisation des archives existent. Elles prouvent l’intérêt qu’y porte une partie de la population, y compris expatriée. Au-delà de ces traits communs, trois destins archivistiques se distinguent : un système malgache encore en construction reposant sur des Archives nationales déjà fortes ; une normalisation progressive à Mayotte sur un modèle départemental ; la faillite du modèle comorien qui bloque tout développement archivistique
Between 1960 and 1975, thanks to the decolonization process, two independent countries and one remaining French territory succeeded the former colony of Madagascar. The question of the evolution of the archival systems in this area, their potential diversification as well as their current maturity, is raised in this context. In Madagascar, in the Comoros as in Mayotte, the creation of archives has not materialized yet and still remains a commendable intention, which results from a lack of funding and because of political instability. Archival organizations fail to preserve all archives and collection focuses on the central level at the expense of the local one. A demand for them exists, but those who show an interest are largely composed of administrative staff and individuals whose documentary needs are often limited to consulting the Official Journal. The success of other research approaches is limited because of the scattering of funds and lack of research tools. Observations of user behaviors confirm the overrepresentation of administrative staff, the weak genealogical research and the existence of circumvention strategies of official conservation organizations. Beside them or out of them, private initiatives of backup and valorization of archives exist. They prove that a part of the population is interested in it, including expatriates. Beyond these common features, three archival destinies stand out : a Madagascan system still under construction based on already strong National Archives ; a gradual normalization in Mayotte on a departmental model; the failure of the Comorian model which hampers all archival development

碩士
實踐大學
資訊科技與管理學系碩士班
97
With the rapid development of wireless networks and devices, the demand for spectrum resource is increasingly growing. Therefore, how to allocate spectrum dynamically to enhance system utility in a multi-user communication system has become an importance issue in recent years. In a multi-user communication system, the transmission quality of each user is affected by not only the channel background noise but also the crosstalk interference from other users, this thesis focuses on allocating the limited power on difference channels for each user to maximize social utility (i.e., the sum of all users’ utilities). Due to the non-convexity of this problem, the CPU time required to solve this problem by the conventional mathematical programming techniques increases greatly as the number of channel and user increases. This thesis proposes an efficient ant colony algorithm to allocate spectrum dynamically for users in order to maximize the social utility. The proposed algorithm integrates the cooling concept of simulated annealing to improve the solution efficiency by enhancing convergence during the local search of the ant colony optimization algorithm. In the computational experiments, the effect of each parameter on the performance of the proposed algorithm is analyzed. Besides, the results obtained by the proposed method are compared with that by the mathematical programming solver, LINGO. Computational results show that the differences in social utility between the proposed algorithm and LINGO are within 0.5% for all cases, and the proposed method outperforms the LINGO in solution time as the number of channel and user increases.

abstract: Persistent cooperation between unrelated conspecifics rarely occurs in mature eusocial insect societies. In this dissertation, I present evidence of non-kin cooperation in the Nearctic honey ant Myrmecocystus mendax. Using microsatellite markers, I show that mature colonies in the Sierra Ancha Mountain of central Arizona contain multiple unrelated matrilines, an observation that is consistent with primary polygyny. In contrast, similar analyses suggest that colonies in the Chiricahua Mountains of southeastern Arizona are primarily monogynous. These interpretations are consistent with field and laboratory observations. Whereas cooperative colony founding was observed frequently among groups of Sierra Ancha foundresses, founding in the Chiricahua population was restricted to individual foundresses. Furthermore, Sierra Ancha foundresses successfully established incipient laboratory colonies without undergoing queen culling following emergence of the first workers. Multi-queen laboratory Sierra Ancha colonies also produced more workers and repletes than haplometrotic colonies, and when brood raiding was induced between colonies, queens of those with more workers had a higher survival probability. Microsatellite analyses of additional locations within the M. mendax range suggest that polygyny is also present in some other populations, especially in central-northern Arizona, albeit at lower frequencies than that in the Sierra Anchas. In addition, analyses of multiple types of genetic data, including microsatellites, the mitochondrial barcoding region, and over 2000 nuclear ultra-conserved elements indicate that M. mendax populations within the southwestern U.S. and northwestern Mexico are geographically structured, with strong support for the existence of two or more divergent clades as well as isolation-by-distance within clades. This structure is further shown to correlate with variation in queen number and hair length, a diagnostic taxonomic feature used to distinguish honey ant species. Together, these findings suggest that regional ecological pressures (e.g. colony density , climate) may have acted on colony founding and social strategy to select for increasing workforce size and, along with genetic drift, have driven geographically isolated M. mendax populations to differentiate genetically and morphologically. The presence of colony fusion in the laboratory and life history traits in honey ant that are influenced by colony size, including repletism, brood raiding, and tournament, support this evolutionary scenario.
Dissertation/Thesis
Doctoral Dissertation Biology 2018

abstract: The most advanced social insects, the eusocial insects, form often large societies in which there is reproductive division of labor, queens and workers, have overlapping generations, and cooperative brood care where daughter workers remain in the nest with their queen mother and care for their siblings. The eusocial insects are composed of representative species of bees and wasps, and all species of ants and termites. Much is known about their organizational structure, but remains to be discovered. The success of social insects is dependent upon cooperative behavior and adaptive strategies shaped by natural selection that respond to internal or external conditions. The objective of my research was to investigate specific mechanisms that have helped shaped the structure of division of labor observed in social insect colonies, including age polyethism and nutrition, and phenomena known to increase colony survival such as egg cannibalism. I developed various Ordinary Differential Equation (ODE) models in which I applied dynamical, bifurcation, and sensitivity analysis to carefully study and visualize biological outcomes in social organisms to answer questions regarding the conditions under which a colony can survive. First, I investigated how the population and evolutionary dynamics of egg cannibalism and division of labor can promote colony survival. I then introduced a model of social conflict behavior to study the inclusion of different response functions that explore the benefits of cannibalistic behavior and how it contributes to age polyethism, the change in behavior of workers as they age, and its biological relevance. Finally, I introduced a model to investigate the importance of pollen nutritional status in a honeybee colony, how it affects population growth and influences division of labor within the worker caste. My results first reveal that both cannibalism and division of labor are adaptive strategies that increase the size of the worker population, and therefore, the persistence of the colony. I show the importance of food collection, consumption, and processing rates to promote good colony nutrition leading to the coexistence of brood and adult workers. Lastly, I show how taking into account seasonality for pollen collection improves the prediction of long term consequences.
Dissertation/Thesis
Doctoral Dissertation Applied Mathematics 2018

The purpose of this paper is to study how color contrast (complementary vs. analogous colors) affect individuals’ emotions and attitudes towards advertisements and purchase intention in the context of online web banner advertisements. Our study found that the complementary color pair of green and red elicited statistically higher levels of pleasure than all other color sets (yellow-violet complementary; orange, orange-red, orange-yellow analogous; and blue, blue-green, blue-violet analogous). Furthermore, the green and red complementary color set had more positive attitudes and higher purchase intentions when used as the background of a web banner advertisement than all over color sets.

This research examines if there are significant differences on the motivation to interact with brands through social media between Generation X and Millennials (also called Generation Y). Furthermore, this study intends to examine if there is a relevant difference in their preference for non-traditional hair colour among these two generational cohorts. Results indicated that Generation Y members consider their relationship with brands as more equal than Generation X. They believe they have the capacity to help a brand succeed or fail especially with their engagement online. Moreover, they are more likely to be active on the Web, and they consider their offline and online worlds as intertwined. Finally, Gen Y is more motivated to consider using non-traditional hair colour than the older cohort. This study fills the gap in the literature by addressing how marketing professionals of the beauty market should market nontraditional hair colour, especially online, based on customers’ generational cohort.

This thesis seeks to discuss the influence of color in work and trade settings, to assess the implications of their applicability in both organizational behavior and retail environment. This investigation was sprung with a preliminary literature review about the influence of space and color in organizational behavior. Subsequently, our major research queries were outlined and three focal studies following a within-subject design about color thus ensued. We first sought to understand the emotional processes behind the choice of complementary colors. Bearing in mind that the literature about complementary colors and emotions is scarce, we analyzed the association between complementary colors and mood states (Chapter I). Through an experimental study, 39 participants were instructed to choose colored cards at four different moments through time, after the induction of an emotional state. Four emotion conditions were evoked by means of autobiographical recall (i.e., happiness, sadness, balanced mood, unbalanced mood). Findings showed that complementary colors were preferred in the unbalanced mood scenario, suggesting that the color choice might rely on partially conscious mechanisms aiming at regaining a balanced state. Secondly, we investigated the interrelation between anthropomorphic packaging and color choices (Chapter II). A total of 259 participants were exposed to non-anthropomorphic and anthropomorphic packaging, considering a product from the real market (Milaneza pasta). Four different color conditions were rated in terms of attractiveness and purchase intention. Our findings suggested that anthropomorphism influenced product’s attractiveness but did not affect purchase intention. Importantly, the green anthropomorphic package produced an almost complementary color contrast between the pasta and the package (vivid green vs. orange-red), leading to a higher color contrast perception that positively affected the product’s attractiveness. In the third study, 436 participants assessed two retail scenarios – orange store and blue store – and two products – chocolate and soap (Chapter III). The products varied in color (red, orange, blue and beige), and were assessed in both stand-alone and embedded in the store situations, through image manipulation. Our results showed that there was a triple interaction resulting from retail environment color × product color × product category. Accordingly, we reinforce the idea that color should not be considered individually, but always in the context where it is inserted. With these three studies, we aim to contribute to the knowledge about the influence of color in human behavior. Crucially, we validate our prediction concerning the presumed effect of complementary colors, both emotionally and in retail settings. Here, we discuss the theoretical and practical implications of these findings.
Nesta tese pretendemos discutir a influência da cor no comportamento organizacional e em contexto de marketing, assim como a aplicabilidade deste conhecimento. A investigação teve início com uma revisão de literatura acerca da influência do espaço e da cor no comportamento organizacional. De seguida, o nosso trabalho começou a delinear-se com maior definição, e foram desenvolvidos três estudos sobre cor, com design intra-sujeitos. Em primeiro lugar, tivemos como objetivo o entendimento sobre os processos emocionais que desencadeiam a escolha de cores complementares. Tendo em conta que a literatura sobre cores complementares e emoções é escassa, analisámos a associação entre cores complementares e estados emocionais (Capítulo I). Através de um estudo experimental intra-sujeitos, 39 participantes escolheram cartões coloridos em quatro momentos diferentes, depois da indução de um estado emocional. Foram induzidas quatro condições emocionais (i.e., felicidade, tristeza, equilíbrio emocional, desequilíbrio emocional) através da redação de um episódio autobiográfico. Os resultados revelaram que os cartões que apresentavam as cores complementares foram preferidos quando o desequilíbrio emocional foi evocado, sugerindo que a escolha de cores pode estar baseada em mecanismos psicológicos parcialmente conscientes, procurando de forma inconsciente recuperar um estado emocional mais equilibrado. Em segundo lugar, investigámos a inter-relação entre embalagens antropomórficas e escolhas de cores (Capítulo II). Um total de 259 participantes escolheram entre embalagens antropomórficas e não antropomórficas, considerando um produto existente no mercado (massa Milaneza). Foram avaliadas quatro cores diferentes em termos de atratividade do produto e intenção de compra. Os resultados mostraram que o antropomorfismo beneficia a atratividade do produto, mas não afeta a intenção de compra. Adicionalmente, a embalagem antropomórfica de cor verde produziu um contraste entre cores quase complementares entre si (verde vívido vs. laranja avermelhado), considerando a massa e a embalagem. Este maior contraste entre cores terá produzido uma perceção que afetou positivamente a atratividade do produto. No último estudo, 436 participantes compararam imagens de dois ambientes de loja – loja laranja e loja azul – e dois produtos – chocolate e sabão (Capítulo III). Os produtos analisados divergiam apenas na cor (vermelho, laranja, azul e bege) e foram avaliados de duas formas: (i) individualmente; e (ii) adicionados ao ambiente de loja através de manipulação digital da imagem. Os resultados demonstraram que houve uma tripla interação resultante do ambiente de loja × produto × categoria de produto. Validámos a ideia de que a cor não deve ser considerada individualmente, mas sempre no contexto onde está inserida. Com estes estudos, pretendemos contribuir para o conhecimento sobre a influência da cor no comportamento humano. O presumido efeito produzido pelas cores complementares, decorrente de fatores emocionais e de perceção, foi validado através da nossa investigação. Por último, implicações teóricas e práticas acerca destes resultados são discutidas.

In the context of the food and beverage category, this academic research was developed to study the impacts that the packaging color has on consumer behavior and product experience. Through an examination of previous researches and undertaking of two experimental studies, several conclusions were drawn. Color is one of the most important elements of a multisensory product packaging design and its functions and roles are manifold and have changed over time. It has the crucial ability to capture the shopper’s attention in-store and due to the fact that packaging is the first point of contact between shoppers and products; its color also conveys information regarding the product’s sensory properties and attributes, in particular, the quality, taste, flavor and healthiness. The impacts of packaging color go beyond the store shelves, it also affects the product’s consumption experience and perception of several sensory attributes. However, the extent and ways packaging colors influence consumers’ behaviors are linked to individual preferences, which are a consequence of demographics variables, such as gender, age, culture and personality. Therefore, packaging color plays an essential role at many stages of consumers’ products experience and should be taken into consideration in order to be translated into brand’s success.
Inserido no contexto da categoria de alimentos e bebidas, a presente pesquisa académica foi desenvolvida com o intuito de estudar os impactos da cor da embalagem no comportamento do consumidor e na experiência do produto. Através de uma análise de pesquisas anteriores e de dois estudos experimentais, foi possível tirar diversas conclusões. Com efeito, a cor é um dos elementos mais importantes do design da embalagem de um produto multissensorial e os seus inúmeros papéis e funções têm mudado ao longo dos tempos. A cor tem como principal capacidade a captação da atenção do consumidor em loja e, uma vez que a embalagem representa o primeiro ponto de contacto entre o consumidor e o produto, a cor também transmite informações relativas às propriedades sensoriais e atributos do mesmo, nomeadamente no que diz respeito à qualidade, sabor e salubridade. O impacto da cor da embalagem vai para além das prateleiras das lojas, dado que também influencia a experiência do produto e a perceção de vários atributos sensoriais durante o consumo. No entanto, a extensão e o modo como as cores da embalagem influenciam o comportamento dos consumidores estão ligadas às preferências individuais, que são uma consequência das variáveis demográficas, como o sexo, idade, cultura e também da personalidade. Nesse sentido, a cor da embalagem pode assumir junto dos consumidores um papel essencial nas diversas etapas da experiência dos produtos. Tendo em conta essa realidade, a sua seleção e aplicação contribuem significativamente para o sucesso de uma marca.

Indiana University-Purdue University Indianapolis (IUPUI)
Given the numerous benefits of a healthy diet and exercise for cancer survivors, there has been an increase in the number of lifestyle intervention trials for this population in recent years. However, the extent to which adherence to a diet and exercise intervention predicts health-related outcomes among cancer survivors is currently unknown. To address this question, data from the Reach out to ENhancE Wellness in Older Cancer Survivors (RENEW) diet and exercise intervention trial were analyzed. RENEW was a yearlong telephone and mailed print intervention for 641 older (>65 years of age), overweight (body mass index: 25.0-39.9), long-term (>5 years post-diagnosis) survivors of colorectal, breast, and prostate cancer. Participants were randomized to the diet and exercise intervention or a delayed-intervention control condition. The RENEW telephone counseling sessions were based on determinants of behavior derived from Social Cognitive Theory (SCT) (e.g., building social support, enhancing self-efficacy). These factors have been hypothesized to improve health behaviors, which in turn should improve health outcomes. Thus, drawing on SCT and prior diet and exercise research with cancer survivors, I hypothesized that telephone counseling session attendance would be indirectly related to health-related outcomes (i.e., physical function, basic and advanced lower extremity function, mental health, and body mass index) through intervention-period strength and endurance exercise and dietary behavior (i.e., fruit and vegetable intake, saturated fat intake). The proposed model showed good fit to the data; however, not all of the hypothesized relationships were supported. Specifically, increased telephone counseling session attendance was related to engagement in all of the health behaviors over the intervention period. In turn, (a) increased endurance exercise was related to improvement in all of the health-related outcomes with the exception of mental health; (b) increased strength exercise was solely related to improved mental health; (c) increased fruit and vegetable intake was only related to improved basic lower extremity function; and (d) saturated fat intake was not related to any of the health-related outcomes. Taken together, these findings suggest that SCT determinants of behavior and the importance of session attendance should continue to be emphasized in diet and exercise interventions. Continued exploration of the relationship between adherence to a diet and exercise intervention and health-related outcomes will inform the development of more cost-effective and efficacious interventions for cancer and other medical populations.