Understanding the Variations in Gibrat's Law with a Markov-Perfect Dynamic Industry Model

Gibrat's Law of proportionate effect, as applied to firms, states that the growth rate of a firm is independent of its size. Empirical work on firm dynamics finds crucial deviations from Gibrat's Law such as smaller firms growing faster than larger firms (Evans, 1987, and Hall, 1987), a negative relationship between the variance of growth rates and size (Dunne and Hughes, 1994), and first-order positive autocorrelation in the growth rates (Kumar, 1995). Moreover, the degree of deviation from Gibrat's Law varies across industries. This paper contributes to our understanding of the forces that make Gibrat's Law a close, but imperfect approximation of firm size distributions and seeks to determine potential sources of cross-industry variation. Here, we employ an extension of the Ericson-Pakes (1995) theoretical framework that allows for firm growth developed by Laincz (2004a). By varying key parameters, the simulations demonstrate potential sources for the various, and sometimes conflicting, results on Gibrat's Law uncovered in the empirical literatureGibrat's Law, Firm Size Distribution, Entry, Exit

A Theoretical Foundation for Understanding Firm Size Distributions and Gibrat's Law

This paper presents a dynamic model of the firm size distribution. Empirical studies of the firm size distribution often compare the moments to a log-normal distribution as implied by Gibrat's Law and note important deviations. Thus, the first, and basic questions we ask are how well does the dynamic industry model reproduce Gibrat's Law and how well does it match the deviations uncovered in the literature. We show that the model reproduces these results when testing the simulated output using the techniques of the empirical literature. We then use the model to study how structural parameters affect the firm size distribution. We find that, among other things, fixed and sunk costs increase both the mean and variance of the firm size distribution while generally decreasing the skewness and kurtosis. The rate of growth in an industry also raises the mean and variance, but has non-monotonic effects on the higher moments.Firm size distribution; Gibrat's Law; R&D.

Using presence-absence data to establish reserve selection procedures that are robust to temporal species turnover

Previous studies suggest that a network of nature reserves with maximum efficiency (obtained by selecting the minimum area such that each species is represented once) is likely to be insufficient to maintain species in the network over time. Here, we test the performance of three selection strategies which require presence-absence data, two of them previously proposed (multiple representations and selecting an increasing percentage of each species' range) and a novel one based on selecting the site where each species has exhibited a higher permanence rate in the past. Multiple representations appear to be a safer strategy than selecting a percentage of range because the former gives priority to rarer species while the latter favours the most widespread. The most effective strategy was the one based on the permanence rate, indicating that the robustness of reserve networks can be improved by adopting reserve selection procedures that integrate information about the relative value of sites. This strategy was also very efficient, suggesting that the investment made in the monitoring schemes may be compensated for by a lower cost in reserve acquisition

Contribuições da gestão de recursos humanos para a criatividade e inovação organizacional

Inovar é, hoje, um imperativo para as organizações. Desse modo, é importante promover a criatividade dos colaboradores e apoiar o processo que a transforma em inovação. O objetivo desta pesquisa foi compreender como a Gestão de Recursos Humanos (GRH) pode promover um ambiente de trabalho propício à criatividade, na perspectiva dos colaboradores. Para isso, realizou-se um estudo de caso exploratório em uma empresa portuguesa de médio porte da área das Tecnologias de Informação (TI). Recorreu-se a diferentes fontes de análise, como observação participante, documentos organizacionais e entrevistas. Os dados resultantes dessas fontes foram analisados e organizados com ajuda da template analysis. Os resultados revelaram que, para as chefias e colaborador entrevistados, a criatividade na organização pode ser promovida por meio da existência de suporte para as novas ideias, tolerância ao erro, autonomia, liberdade para que os colaboradores exerçam suas funções e debates para a partilha de ideias. A GRH pode criar condições, por meio das suas práticas (p. ex., formação, avaliação de desempenho, recrutamento e seleção), para a promoção da criatividade e inovação organizacional.Innovation is a key factor to organizations’ competitiveness. To achieve that, it is important to promote creativity among employees and support the transformational process from creativity to innovation. The main objective of this research was to understand how Human Resource Management (HRM) can promote a work environment favorable to creativity, from the perspective of the employees. A case study was carried out on a medium-sized Portuguese information technology (IT) enterprise. Various research techniques were used to collect data, including observation, document analysis, and interviews. Data were organized and analyzed using a template analysis. The results revealed that, for the respondents (managers and employee), creativity within the organization can be promoted by the existence of support for new ideas, error tolerance, autonomy, freedom for employees to perform their tasks, and discussions to share ideas. HRM can create conditions, through their practices (e.g., training, performance evaluation, recruitment, and selection), to promote organizational creativity and innovation

Between Husband and Father: Queen Isabel of Lancaster’s crossed loyalties

Isabel of Lancaster became engaged to Afonso V of Portugal when they were both seven years old. Her father was Pedro, the uncle of the infant king and regent of the realm after the forcing out of the qneen rnother Leonor of Aragon. The regency allowed Pedro to favoiir his own lineage. However, when Afonso V took over the governinent, other branches of the roya1 family and the high nobility who felt endangered by Pedro's policy started to turn the king against him. We will show how Isabel negotiated her loyalty both to her husband and to her fatber during the conflict that arose between thern, and how she managed to keep her status and power while honouring her father's memory and protecting the other women of her lineage after thc ignominious death of Pedro in a battle against the king.info:eu-repo/semantics/publishedVersio

Gendering medieval Portugal

This work is financed by national funds through FCT - Foundation for Science and Technology, I.P.info:eu-repo/semantics/publishedVersio

Exploring nutrient supplementation and bioprocess optimization to improve the production of lentiviral vectors in serum-free medium suspension cultures

Funding Information: T.A.V. acknowledges FCT for the award of the individual grant SFRH/BD/145270/2019. This work was funded by Fundação para a Ciência e Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior (FCT/MCTES, Portugal) through national funds to iNOVA4Health (UIDB/04462/2020 and UIDP/04462/2020) and the Associate Laboratory LS4FUTURE (LA/P/0087/2020). Publisher Copyright: © 2023 The Authors. Biotechnology Journal published by Wiley-VCH GmbH.The use of lentiviral vectors (LV) in gene therapy has been growing in recent years. To meet the increasing clinical demand, LV production platforms will benefit from improved productivity and scalability to enable cost-effective manufacture of LV-based therapies. Here we report the adaptation of 293T cells to serum-free suspension cultures and the improvement of LV yields through transfection parameters optimization, process intensification and medium supplementation with nutrient boosters. Cells were sequentially adapted to different serum-free culture media, transfection parameters were optimized and the two best-performing conditions were selected to explore process intensification by increasing cell density at the time of transfection. LV production at higher cell densities increased volumetric titers up to 12-fold and lipid supplementation was the most efficient metabolic optimization strategy further enhancing LV productivity by 3-fold. Furthermore, cell concentration was identified and validated as an important source of transfection variability impairing cellular uptake of DNA polyplexes, impacting transfection efficiency and reducing LV titers down to 6-fold. This work contributes to improving LV-based gene therapy by establishing new scalable manufacturing platforms and providing key metabolic insights, unveiling important bioreaction parameters to improve vector yields.publishersversionpublishe

Exploring the benefits of using a mixed methods approach in destination image studies

This study aims to demonstrate that mixed-methods are suitable when assessing the image of a tourism destination. Depict the image attributes that influence a lake destination area and conceptualize lake tourism are the goals of this study. Lake tourism is a growing academic field of tourism studies. However, little attention has been given to tourism images. The case is the newly-formed Alqueva Lake, Portugal, the biggest man-made lake in Europe. A mixed-design method was adopted, particularly a complementarity approach. The data were first collected in the qualitative stage, then analysed. Results were used to develop a follow-up questionnaire. A set of image attributes that best describe Alqueva Lake was obtained and validated. The advantages of adopting mixed-methods to studies about destination image are discussed

Biosurfactants: production, applications and future potential

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Surfactants are one of the most important classes of industrial chemicals in terms of production volume. These compounds exhibit a wide variety of applications in several industries and are present in nearly every product and aspect of our daily life. They can be found in detergents, laundry formulations, household cleaning products, cosmetics, herbicides or pesticides, and are also used in bioremediation, agriculture, food, pharmaceutical, textile, paper or the petroleum industries, among others. Most conventional surfactants available nowadays are derived from non-renewable resources and their use may lead to significant ecological problems due to their toxicity and low biodegradability. In the recent years, an increase in environmental awareness has led to much more interest in the use of renewablebased, biodegradable and more environmentally friendly surfactants. Among them biosurfactants, surface-active compounds synthesized by microorganisms, are attracting a pronounced interest due to their potential advantages over their synthetic counterparts, and to the fact that they could replace some of the synthetics in many environmental and industrial applications. [...]info:eu-repo/semantics/publishedVersio

Processamento de imagem digital com MatLab : uma aplicação em ambiente industrial

Fundação para a Ciência e a Tecnologia (FCT