Does corporate governance affect stock liquidity in the Tunisian Stock Market?

The aim of the current paper is to study the link between the effects of corporate governance on information asymmetry problems and stock liquidity in the Tunisian Stock Market. We use a sample of 49 Tunisian firms listed between 1998 and 2007. Our results show that corporate governance has direct and indirect effects on stock liquidity. Threat of expropriation exerted by family and foreign shareholders discourages reluctant investors,which decreases stock liquidity. In contrast, they invest their capital in State controlled firms. In fact, State is regarded as an effective controller rather than a shareholder. The State involvement in Tunisian firms is considered as state guarantee for investors, which increases stock liquidity. Our results provide evidence that some attributes of corporate governance improve stock liquidity because they reduce information asymmetry.corporate governance, shareholder identity, stock liquidity, Tunisian Stock Exchange

Firm's information environment and stock liquidity: evidence from Tunisian context

This paper analyzes the relationship between public disclosure, private information and stock liquidity in the Tunisian market. We use a sample of 41 listed firms in the Tunis Stock Exchange in 2007. First, we find no evidence that there is a relation between public and private information. Second, Tunisian investors do not trust the information disclosed in both annual reports and web sites, consequently it has no effects on stock liquidity, in contrast with private information.corporate information disclosure, private information, stock liquidity, emerging market.

The Characterization of a Newly Layered Bimetallic Hydrogen Selenite Copper-Selenium: Synthesis and Structure

Single-crystal X-ray diffraction data were used to solve the structure of a newly layered copper-selenium hydrogen selenite and further refined to a final reliability factor, R1 = 0.038. This structure was found to have an orthorhombic space group PBn21, with a = 7.1753(4) Å, b = 9.0743(4) Å, c = 17.725(9) Å, V = 1154.06(10) Å3, and Z = 4. Although this structure may be described to exhibit a bidimensional structure, it is actually three-dimensional in shape. The bidimensional structure is made up of layers, parallel to the (010) plane, which contain copper atoms and (HSeO3)− anions with sheets interconnected by [CuCl3(H2O)3] groups. Bond valence sum calculations were used to evaluate the Se and Cu oxidation states. Both the infrared (IR) and Raman spectra were obtained and employed to confirm the presence of hydrogen selenites (Se─O─H). Also, the dielectric constant at different frequencies and temperatures revealed a phase transition at 383 K

Development and characterization of smart edible films

Mestrado de dupla diplomação com a Université Libre de TunisPackaging is a very important tool to prevent food waste and ensure the product desired quality along shelf life. Beyond protecting foodstuff and helping to store it in hygienic conditions, packaging can also be helpful in indicating the overall condition of the contained food. These systems that monitor/communicate food quality and safety are known as smart/intelligent packaging and are increasingly used in food industry. However, a large amount of packaging is derived from synthetic polymers and represents a major obstacle to the sustainable development of a country, as it causes several negative impacts on nature for being nonbiodegradable. In this context, biodegradable packaging that could also permanently indicate the quality status of a product and share this information with the consumer is a challenger innovation path in food science with great potential to be absorbed in the industry. A possible way to detect food deterioration is through pH changes, which can be caused by various factors as microbial spoilage or oxidation mechanisms, among others. Through the addition of compounds that undergo easily detectable coloration changes with pH variation, as anthocyanins, biodegradable smart films can be developed, which was the main goal of this project. To obtain the edible films, cassava starch was used together with glycerol, an important plasticizer, and anthocyanin-rich extract obtained from P. spinosa epicarp was also added to act as a pH indicator. The extract, obtained under previously optimized conditions, was tested for its chromatographic and bioactive profile. The most abundant anthocyanin compounds were cyanidin-3-O-rutinoside ([M+H]+ at m/z 595) and peonidin- 3-O-rutinoside ([M+H]+ at m/z 609), presenting a total anthocyanin content of 8.05±0.07 mg/g of extract. The extract also showed great antimicrobial activity, mainly against Salmonella enterica, with a MIC of 2.5 mg/mL, and against Escherichia coli, Staphylococcus aureus, and Aspergillus fumigatus with a MIC of 5 mg/mL. In addition, it showed a strong antioxidant activity against lipid peroxidation (TBARS assay), with an EC50 value thirteen times lower than that presented by the positive control, Trolox (10.4 ± 0.5 and 139 ± 5 μg/mL, respectively). These results support to the potential use of the extract in smart films. For the films formulation based on cassava starch and glycerol dissolved in water, five studies were selected from the literature. The formulations were reproduced to define the ideal conditions. Two good formulations were achieved: with 0.5 g or 0.8 g of glycerol, in 100 g of water, 3 g of cassava starch, and 1 g of anthocyanins. For control samples, anthocyanin-rich extracts were not added. By testing different formulations, it was possible: to save energy, by choosing the lower temperature tested (70 °C) for gelation process; to save the degassing process by not forming bubbles at this temperature; and to verify the influence of each condition in the film formation process. The gelation temperature and relative humidity control during the drying process had the most important influence on the success of film manufacturing. Subsequently, the visual effects observed by varying the proportions of the ingredients were supported by FTIR and SEM evaluation. Overall, it was possible to conclude that the formulations presented good homogeneity and cohesion. The increase in glycerol from 16.6 to 26.6 g/100g of starch affected some bands in the FTIR spectra, also being observed by lower surface resistance by SEM. As for the addition of anthocyanins, this factor did not cause a major impact on the FTIR spectra and, despite resulting in rougher surfaces evaluated by SEM, the extract is applicable to films. Furthermore, when tested in different pH solutions, the colour of the films was effectively changed, thus reinforcing the applicability of the anthocyanin extract in films based on cassava starch and glycerol, with potential application for monitoring pH changes in food products

Stock Liquidity, Feedback Prices, And Asset Liquidity: Evidence From The Tunisian Stock Market

This paper explores how feedback prices influence firms' investment on asset liquidity through stock liquidity. Using a sample of the Tunisian listed firms between 1999 and 2010, empirical results confirm that stock market liquidity plays a significant role in investment decisions and show that high stock liquidity encourages firms to invest more on asset liquidity to overcome feedback prices (negative and positive feedback). Therefore, the paper’s findings demonstrate the link between stock markets and the current business activity of the firm. Furthermore, the results indicate how stock liquidity strengthens feedback prices effects on managerial decisions and choices, which highlights the importance of stock liquidity

CONSÉQUENCES DE L'ADOPTION DES NORMES INTERNATIONALES «IFRS» SUR LE COÛT D'AUDIT FINANCIER*

Ce travail a pour objectif de chercher, dans un contexte français, les conséquences de l'adoption des normes « IFRS » sur la mission et le coût de l'audit légal/financier. En effet, l'Union Européenne a rendu obligatoire, au 1er Janvier 2005, l'application d'un référentiel comptable international commun pour toutes les sociétés cotées sur un marché financier en Europe. Un examen des enquêtes et des études qui ont été réalisées montre que cette opération n'était pas facile, ni sans coût ni pour la firme concernée, ni pour l'auditeur légal. Sur un échantillon formé de 106 sociétés françaises du SBF 250 couvrant la période 2002-2007, les résultats trouvés montrent une augmentation significative des honoraires d'audit la période de l'adoption des normes IFRS (2004 et 2005). Les hypothèses liées à la taille de la firme auditée, à son niveau d'endettement, au % du capital détenu par les actionnaires de référence, au nombre des auditeurs Big 4 et à la durée de la relation entre l'auditeur et l'audité sont aussi confirmées. Par contre les hypothèses liées au risque inhérent et au % du capital détenu par les dirigeants sont infirmées.IFRS, audit légal/financier, risque d'audit, coût d'audit

Sustainable value creation in fruit and vegetable companies: A case study

The increasing demand for sustainable products along with environmental and social concerns have prompted fruit and vegetable companies to move from classical to novel, sustainable business models through the implementation of sustainability practices. This study intends to explore this process of change using the Triple Layered Business Model Canvas (TLBMC). The theoretical framework of the TLBMC has been applied in a selected fruit and vegetable Spanish company. Based on the TLBMC depicted for the company, new business models could be generated by innovating strategically in a series of areas to improve the value proposition in terms of sustainability objectives. The suggested model provides an accessible representation of the company business system allowing to guide the creative process of presenting, communicating and implementing business model innovation

L'analyse de l'impact des mécanismes de gouvernance sur le niveau de divulgation volontaire : Cas des sociétés tunisiennes non financières

Cette étude examine les aspects de la gouvernance qui incitent les dirigeants à publier volontairement des informations dans leurs rapports annuels dans un contexte de concentration de propriété. Elle examine les relations entre la publication volontaire et la structure de propriété, le conseil d'administration et les autres mécanismes de contrôle. Les résultats de l'analyse multi variée montrent que la concentration de propriété a un effet négatif et significatif sur le niveau de divulgation volontaire. Cette même relation est trouvée lorsque le détenteur de bloc de contrôle est un individu. Ce pendant, lorsque l'Etat est le détenteur de bloc de contrôle, la relation est positive et significative.Divulgation volontaire; gouvernement d'entreprise; structure de propriété; coûts d'agence

A new approach to gather similar operations extracted from web services

A web service is an autonomous software that exposes a set of features on the Internet, it is developed and published by providers and accessed by customers who discover it, select it, invoke and use it. Several research policies have been implemented such as searching through keywords, searching according to semantics and searching by estimating the similarity. A customer is looking for a service for the operations he/she carries out, hence the interest of guiding the search for services towards a search for operations: finding the desired operations amounts to finding the services. For this, groupings of similar operations would make it possible to obtain all the services that can meet the desired functionalities. The customer can then select, in this set the service or services according to its non-functional criteria. The paper presents a study of the similarity between operations. The proposed approach is validated through an experimental study conducted on web services belonging to various domains