Abstract
In this paper we address the problem of maximizing the expected number of transplants in a kidney exchange program. We propose an integer programming model with an exponential number of decision variables which are associated with cycles. By introducing the concept of type of cycle, we avoid the complete cycle enumeration and develop a branch-and-price approach. © 2016 Elsevier B.V.

Abstract
Personnel scheduling problems are widely studied both by the scientific community and by the human resource managers of the companies. The financial impact of the decisions, the welfare of the employees, or more subjective concepts like "fairness" and "balance", turn this case into much more than just a routine problem. When it comes to medical personnel scheduling, additional difficulties can be found, such as uninterrupted work (24 hours per day, 7 days per week), or the quality of service that has to be ensured. The work presented in this paper was based on the rules defined in INRCII - Second International Nurse Rostering Competition - but always with the vision of creating the necessary basis for the future development of an automatic and optimized generic personnel scheduling software.

Abstract
At a time when the need to reduce costs has become part of the day-to-day reality of all educational institutions, it is unthinkable to continue to manually perform those tasks (i.e., the creation of timetables) that can be automated and optimized. The automatic creation of timetables for educational institutions is one of the most studied problems by the scientific community. However, almost all studies have been based on very simplified models of reality that have no practical application. A realistic model of the problem, robust algorithms that are able to find valid solutions in highly restricted environments, and optimization methods that are able to quickly provide quality results are key factors to consider when attempting to solve this (real) problem faced by educational institutions. This paper presents a summary of the work performed by Bullet Solutions over the last few years, from the first stage of understanding and modelling the problem to the final analysis of the results obtained using the developed software under real conditions.

Abstract
Online gambling has skyrocketed in recent years. As such, knowing the determinants of consumer usage behavior is crucial in understanding online gambling services. This study has as main objective the construction of an explanatory model of the online gambling services usage behavior, based on the incorporation of perceived risk in the conceptual framework of the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2). The empirical validation of the model was performed by conducting an online survey to a convenience sample of 212 Portuguese online players. Data were processed using the PLS-SEM methodology. The results evidence that performance expectancy, social influence, facilitating conditions, hedonic motivations, price value, habits, as well as perceived risk influence the intention to use online gambling services.

Abstract
This chapter describes the market entry process of Portuguese small and medium-sized enterprise (SME) into the Brazilian. This chapter explores an under-researched strand in the studies of internationalization of SMEs, namely how trust and commitment leveraged the relationship orientation of the Portuguese SME in entering into the Brazilian market. Through a Case Study the chapter explores the concept of relationship orientation, trust and commitment to analyze how a Portuguese SME managed to turn around a difficult situation transforming its associates in business partners and prevented a process of desinternationalization. © 2016 by IGI Global.

Abstract
Purpose - The purpose of this paper is to identify and compare different groups of customers' perceptions (i.e. stayers, switchers, and heavy switchers) of several loyalty antecedents such as satisfaction, trust, service quality, switching costs, marketing communication, and loyalty itself. Design/methodology/approach - This study was carried out based on data collected through a questionnaire from 353 telecommunication services users in Portugal and using confirmatory factor analysis (CFA) and analysis of variance. Findings - The three types of customers - stayers, switchers, and heavy switchers - clearly differ among themselves. Stayers differ from switchers regarding their communication efforts perceptions, and from heavy switchers in their loyalty, satisfaction, and trust levels. Switchers differ from heavy switchers in their loyalty levels. Research limitations/implications - Future research should examine differences between customers taking into account the impact of their personality, price sensitiveness, and orientation toward the adoption of new technologies. Practical implications - As there are several differences among stayers, switchers, and heavy switchers, companies should not only recognize the heterogeneity of their customer base, but also target their marketing efforts accordingly. Originality/value - This study is one of the few identifying groups of customers perception's toward service providers. It also complements previous research by splitting them intro three different groups and by analyzing their behaviors across a set of previously unexamined marketing variables.