Paying not to sell

In this paper we show that, in the presence of buyer and seller power, a monopolist can enter into a costly contractual relationship with a low-quality supplier with the sole intention of improving its bargaining position relative to a high-quality supplier, without ever selling the good produced by that firm

FORMULATION AND ASSESSMENT OF A HERBAL HAIR CREAM AGAINST CERTAIN DERMATOPHYTES

Objective: Developing an herbal antifungal formulation containing eruca and garlic oils against highly resistant dermatophytes (Malassezia fufur AUMC No. 5173, Microsporum canis bodin AUMC No. 5490 and Trichophyton mentagrophytes AUMC No. 5501. 5501) and assessment of garlic oil thiosulfonates during the ex vivo percutaneous permeation through albino rat skin.Methods: Assay of antifungal activity was performed by filter paper disc method and agar well diffusion method. The components of volatile constituents and fixed oil of eruca seeds were studied using GC/MS. Thiosulfinates in garlic oil were analyzed by HPLC/UV. Both oils were incorporated into hair cream using span 60 and brij 58 at three different concentrations (2, 4 and 6% w/w) and alliin, was ex vivo evaluated using albino rat skin mounted on Franz diffusion cells.Results: The two oils have a synergistic effect on the first and additive effect on the second and the third fungi. The main constituents in eruca are 4-(methyl thio) butyl isothiocyanate (82%) for volatile constituents and erucic acid (40%) for the fixed one. The highest flux for alliin (0.337±0.0015 mg/cm2/hr) was obtained at a 4% surfactant concentration.Conclusion: Combination of oils has a high activity on the selected dermatophytes. Formulation of an herbal hair cream using span 60 and Brij 58 with a concentration 4% gives the highest permeation rate for alliin in garlic oil.Keywords: Eruca, Garlic, Dermatophytes, Quantitative determination and Ex-vivo permeatio

Clinical characteristics and outcomes of critically ill COVID-19 patients in Sfax, Tunisia

Background Africa, like the rest of the world, has been impacted by the coronavirus disease 2019 (COVID-19) pandemic. However, only a few studies covering this subject in Africa have been published. Methods We conducted a retrospective study of critically ill adult COVID-19 patients—all of whom had a confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection—admitted to the intensive care unit (ICU) of Habib Bourguiba University Hospital (Sfax, Tunisia). Results A total of 96 patients were admitted into our ICU for respiratory distress due to COVID-19 infection. Mean age was 62.4±12.8 years and median age was 64 years. Mean arterial oxygen tension (PaO2)/fractional inspired oxygen (FiO2) ratio was 105±60 and ≤300 in all cases but one. Oxygen support was required for all patients (100%) and invasive mechanical ventilation for 38 (40%). Prone positioning was applied in 67 patients (70%). Within the study period, 47 of the 96 patients died (49%). Multivariate analysis showed that the factors associated with poor outcome were the development of acute renal failure (odds ratio [OR], 6.7; 95% confidence interval [CI], 1.75–25.9), the use of mechanical ventilation (OR, 5.8; 95% CI, 1.54–22.0), and serum cholinesterase (SChE) activity lower than 5,000 UI/L (OR, 5.0; 95% CI, 1.34–19). Conclusions In this retrospective cohort study of critically ill patients admitted to the ICU in Sfax, Tunisia, for acute respiratory failure following COVID-19 infection, the mortality rate was high. The development of acute renal failure, the use of mechanical ventilation, and SChE activity lower than 5,000 UI/L were associated with a poor outcome

Essais sur l’innovation environnementale : le rôle des relations verticales et despolitiques publiques

The innovation of the 21st century has no longer as a mere objective the survival of companies in the market and the stimulation of the growth at the country level. From now on, there is an urgent need to preserve the environment to ensure the development of present and future generations. Therefore, several empirical studies and theoretical accounts place the matter at the heart of innovation and economics fields of research. The first objective of this dissertation is to examine how ‐at a microeconomic level‐ the emergence and diffusion of environmental innovations is impacted by strategic inter‐firm relationships within supply‐chains. In order to achieve this goal, the first chapter shows that a monopoly maintains on the market a low‐quality product in the sole intention to increase his bargaining power against a supplier offering a drastic innovation ‐a costless high‐quality product‐. The second chapter explains how bargaining powers between vertically related firms can influence the adoption choice of environmental technology leading to a sub‐optimal level of depollution or welfare. To deal with this situation, the regulator must adapt its regulatory policy ‐a tax in this case‐ to modify the choice of the polluting firm. However, its intervention may prove insufficient under certain conditions. The second objective of the dissertation is developed in the third chapter which identifies theoretically and empirically the macroeconomic determinants of environmental innovations in order to help the regulator to better target its interventions.L’innovation du 21ème siècle n’a plus comme simple objectif la survie des entreprises sur le marché et la relance de la croissance des pays. Désormais, elle doit, en plus, préserver l’environnement pour assurer le développement des générations actuelles et futures. Cette nouvelle tâche la place au centre des recherches d’innombrables travaux mobilisant les champs de l’économie de l’innovation et de l’économie environnementale. L’ambition de cette thèse est, dans un premier temps, d’examiner comment ‐à un niveau micro‐économique‐, l’émergence et la diffusion des innovations environnementales sont impactées par les relations stratégiques inter‐firmes au sein des chaînes de valeur. Pour ce faire le premier chapitre montre qu’un monopole est prêt à maintenir sur un marché un produit de moins bonne qualité pour augmenter son pouvoir de négociation face à un fournisseur offrant une innovation drastique –un produit de meilleur qualité sans coûts additionnels‐. Le second chapitre explique comment les pouvoirs de négociation entre les firmes verticalement liées peuvent influencer le choix de l’adoption de la technologie environnementale engendrant un niveau de dépollution ou de bien‐être sous‐optimal. Pour faire face à une telle situation, le régulateur doit adapter sa politique de régulation –une taxe en l’occurrence‐ pour modifier le choix de la firme polluante. Or son intervention peut se révéler insuffisante sous certaines conditions. Dans un deuxième temps, le troisième chapitre cette thèse identifie, théoriquement et empiriquement les déterminants macro‐économiques des innovations environnementales afin d’aider le régulateur à mieux cibler ses interventions

Monopoly and technology choice: the impact of environmental taxes and bargaining

International audienc

Strategic use of environmental innovation in vertical chains and regulatory attitudes

We analyze firms' choice of abatement technology in vertical chains. A downstream polluting monopoly can buy a license from an upstream supplier with mature end-of-pipe equipment (outsider) or develop an in-house clean technology. Insiders innovation may be undertaken only to increase bargaining power of the polluter. We put the light on the strategic role of environmental regulation to influence this choice. We find that the role of regulator as a technology forcing authority is confirmed in regions of under-investment. However, under certain conditions, an over-investment occurs that forces the regulator to become laxer. Paradoxically, the regulator may oppose innovation even if the resulting technology is used by the innovator. All these results rely upon the creation of total profits from the integrated vertical structure

Monopoly and technology choice: the impact of environmental taxes and bargaining

National audienc

Monopoly and technology choice: the impact of environmental taxes and bargaining

National audienc

Monopoly and technology choice: the impact of environmental taxes and bargaining

National audienc

Monopoly and technology choice: the impact of environmental taxes and bargaining

International audienc