Optimal choice between even- and uneven-aged forestry: the case of non-industrial private forest owners

An infinite-horizon discrete time model with multiple size-class structures using a transition matrix is built to assess optimal harvesting schedules in the context of Non-Industrial Private Forest (NIPF) owners. Three model specifications accounting for forest income, financial return on an asset and amenity valuations are considered. Numerical simulations suggest uneven-aged forest management where a rational forest owner adapts her or his forest policy by influencing the regeneration of trees or adjusting consumption dynamics depending on subjective time preference and market return rate dynamics on the financial asset. Moreover she or he does not value significantly non-market benefits captured by amenity valuations relatively to forest income.

Ethical leadership and unethical pro-organizational behavior: A moderated mediation model of affective commitment and authenticity at work

Recently, unethical conduct in the workplace has been a focus of literature and media. Unethical pro-organizational behavior (UPB) refers to unethical conduct that employees engage in to benefit the organization. Given the complexity of UPB, there is an increasing need to understand how and under what conditions this attitude originates within organizations. Based on a sample of 167 employees and seven organizations, results support the moderated mediation model. An ethical leader increases employees’ organizational affective commitment which increases the likelihood to engage in UPB. However, the indirect relationship diminishes when employees feel authentic at work.

Optimal design and operation of compact simulated moving bed processes for enantioseparations

Simulated moving bed (SMB) chromatography is attracting more and more attention since it is a powerful technique for complex separation tasks. Nowadays, more than 60% of preparative SMB units are installed in the pharmaceutical and in the food in- dustry [SDI, Preparative and Process Liquid Chromatography: The Future of Process Separations, International Strategic Directions, Los Angeles, USA, 2002. http://www. strategicdirections.com]. Chromatography is the method of choice in these ¯elds, be- cause often pharmaceuticals and ¯ne-chemicals have physico-chemical properties which di®er little from those of the by-products, and they may be thermally instable. In these cases, standard separation techniques as distillation and extraction are not applicable. The noteworthiness of preparative chromatography, particulary SMB process, as a sep- aration and puri¯cation process in the above mentioned industries has been increasing, due to its °exibility, energy e±ciency and higher product purity performance. Consequently, a new SMB paradigm is requested by the large number of potential small- scale applications of the SMB technology, which exploits the °exibility and versatility of the technology. In this new SMB paradigm, a number of possibilities for improving SMB performance through variation of parameters during a switching interval, are pushing the trend toward the use of units with smaller number of columns because less stationary phase is used and the setup is more economical. This is especially important for the phar- maceutical industry, where SMBs are seen as multipurpose units that can be applied to di®erent separations in all stages of the drug-development cycle. In order to reduce the experimental e®ort and accordingly the coast associated with the development of separation processes, simulation models are intensively used. One impor- tant aspect in this context refers to the determination of the adsorption isotherms in SMB chromatography, where separations are usually carried out under strongly nonlinear conditions in order to achieve higher productivities. The accurate determination of the competitive adsorption equilibrium of the enantiomeric species is thus of fundamental importance to allow computer-assisted optimization or process scale-up. Two major SMB operating problems are apparent at production scale: the assessment of product quality and the maintenance of long-term stable and controlled operation. Constraints regarding product purity, dictated by pharmaceutical and food regulatory organizations, have drastically increased the demand for product quality control. The strict imposed regulations are increasing the need for developing optically pure drugs.(...)

Fishing the key biological components of the bacterium Geobacter metallireducens for optimal biotechnological applications

Os resultados apresentados no capítulo 2 foram incluídos no artigo Dantas JM, Campelo LM, Duke NEC, Salgueiro CA, Pokkuluri PR (2015) "The structure of PccH from Geobacter sulfurreducens – a novel low reduction potential monoheme cytochrome essential for accepting electrons from an electrode", FEBS Journal, 282, 2215-2231.

Influence of employee volunteering on brand commitment

Purpose – The purpose of this paper is to explore the impact of corporate volunteering on employee bonding and to understand the barriers and motivation to participation in these events. In contrast to other studies the participants volunteer in their spare time without expecting any financial reward. Design/methodology/approach – Employees (n 3951) of a logistic company participated in the study based on an online questionnaire with 6 items and open questions. The employee sample was divided into 3 groups depending on the frequency of participation in volunteering events. Findings – Significant differences were found on bonding between the three groups. In addition, the relevance of control variables like gender, age and job level were obtained. Furthermore a moderation effect of motivation was found. The results were interpreted within the broader context that ties motivation theory, organizational identification and social exchange theory.

Perception of organizational politics and the effect of authenticity and affective commitment on deviance and task performance in contact centers

This study aimed to understand employees’ reactions to organizational politics in Contact Centers. Drawing from a sample of 187 supervisor-employee dyads, we studied the relationship between employees’ perceptions of organizational politics and supervisor-rated task performance and deviance, and mediation effects by authenticity at work and affective commitment. Results indicate that workers tend to react to workplace politics with deviant behavior and worse task performance. We found that the relationship between perceived politics and task performance was mediated by authenticity. The relationship between perceived politics and supervisor-rated deviance was mediated by affective commitment to the organization. Implications for management are discussed.

An analysis of associations between human resources practices, affective commitment, exhaustion and cynicism of temportary workers

This research examines the relationships between Human Resources Practices (HRP) and affective commitment, exhaustion, and cynicism of temporary workers. Furthermore, voluntariness and tenure with the client organization are assumed in the analysis as moderators. A sample of Temporary Agency workers was surveyed. It was assumed that HRP positively relates with affective commitment, while negatively with exhaustion and cynicism. Results confirmed the proposed relationships. Regarding the moderators, it has been proved that voluntariness partially weakens the relationships between HRP and temporary workers’ outcomes. However, contrary to the hypothesis, this effect cannot be affirmed also for the tenure with the client organization. Previous literature as well as implications of the findings are discussed.

Harvest control rule vs optimal harvesting of an age-structured population: The case of the Ibero-Atlantic Sardine Fishery

Research Masters