Does income inequality matter for economic growth? : An empirical investigation

In this paper we empirically investigate a possible effect of income inequality on growth. Using a panel of 126 countries for the time-span from 1968 to 2007 we report a positive relationship between income inequality and growth. That occurs through both the taxation and the human capital channels. We estimate our model with several estimation techniques such as fixed effects, GMM and Two stages least squares. Our results suggest that a policy maker has to take into account a certain trade off between making the distribution of income more equal and raising the economy's wealth

Does income inequality matter for economic growth? : An empirical investigation

In this paper we empirically investigate a possible effect of income inequality on growth. Using a panel of 126 countries for the time-span from 1968 to 2007 we report a positive relationship between income inequality and growth. That occurs through both the taxation and the human capital channels. We estimate our model with several estimation techniques such as fixed effects, GMM and Two stages least squares. Our results suggest that a policy maker has to take into account a certain trade off between making the distribution of income more equal and raising the economy's wealth

In Vitro and Ex Vivo Evaluation of Tablets Containing Piroxicam-Cyclodextrin Complexes for Buccal Delivery

In the current study, the development of mucoadhesive tablets for buccal delivery of a non-steroidal anti-inflammatory drug was investigated. Binary complexes with piroxicam and cyclodextrins (beta-cyclodextrin (b-CD), methylated-beta-cyclodextrin (Me-b-CD), and hydroxypropyl-beta-cyclodextrin (HP-b-CD)) were prepared by the co-evaporation method. All formulations were characterized by means of diferential scanning calorimetry, infrared spectroscopy and powder X-ray diffractometry. Mucoadhesive tablets of binary systems were formulated by direct compression using chitosan as mucoadhesive polymer. The in vitro release profiles of tablets were conducted in simulated saliva and, the drug permeation studies, across porcine buccal mucosa. The results suggest that the rank order effect of cyclodextrins for the drug release was Me-b-CD >HP-b-CD > b-CD, whereas the ex vivo studies showed that the tablets containing chitosan significantly increased the transport of the drug compared to their free complexes. Finally, histological assessment revealed loss of the superficial cell layers, which might be attributed to the presence of cyclodextrins

Fibrous polymeric buccal film formulation, engineering and bio-interface assessment

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Polymer based dosages form the mainstay of drug delivery systems either as simple matrix carrier materials or active release behavior modulating agents. In addition, several techniques have been developed further to deliver novel polymeric structures. One such method is electrospinning (ES); a maturing process which is operational at the ambient environment and enables drug loading (in molecularly dispersed form) directly into a fibrous polymer matrix system. Since there is an impending need to address healthcare challenges arising from an increase in the aging population (requiring enhanced treatments), the ES method was used to develop fibrous polymer composite-indomethacin (INDO) films for potential use in the buccal region. Films were assessed for their inter-facial behavior at bio-interfaces (in-vitro and ex-vivo). Polymeric excipients possessing an established profile for commercial dosage form development were selected. Fibrous films (all fibre components <400 nm) were characterised using DSC, TGA, FTIR, Raman and XRD. DSC and XRD demonstrated INDO change from crystalline to amorphous state. FTIR and Raman data suggest INDO, PVP and co-polymers (Methocel™ E5, Methocel™ E15 and Tween® 80) were integrated in stable fashion into filamentous structures via ES. Variable INDO release behavior from several matrices was observed suggesting a potential route to tailor drug release based on polymeric excipient use and ratio. Furthermore, permeation studies using a porcine buccal model demonstrated sustained permeation once dosages are attached to the buccal mucosa. The insoluble nature of cellulose excipients were used to promote sustained release while the use of Tween® 80 surfactant was used to enhance permeation of INDO through polymer interaction with excised tissue. Finally, histology studies indicate polymer excipient selection impacts the bio-interface. In summary, a facile approach to formulate, encapsulate and engineer fibrous polymeric buccal films (on demand) is shown. The method enables drug dispersion directly within the composite polymeric system, which has a clear impact on drug release, in-vitro and ex-vivo bio-interaction

Probing the perturbation of lecithin bilayers by unmodified C60 fullerenes using experimental methods and computational simulations

In this study, we aimed to use physicochemical and theoretical tools to understand fundamental problems of the interaction between lipid bilayers (Egg-PC liposomes) and unmodified C60 fullerenes. The morphology, the size, and the electrokinetic properties of plain and C60-loaded liposomes were investigated by means of atomic force microscopy, dynamic light scattering, and ?-potential studies, respectively. The incorporation of C60 molecules into the liposomes increases their size; however, there was no effect on their electrokinetic properties. Visualization studies revealed that the presence of C60 in the membranes induced distortion in vesicle morphology, resulting in nonspherical vesicles. To elucidate further the impact of C60 molecules on lipid bilayers, we assessed their miscibility by fluorescence spectroscopy measurements. Fluorescence measurements showed that the presence of C60 in liposomes causes a pronounced effect on the Nile red emission spectrum due to alterations to the packing of the lipid membrane. The release of vesicle-encapsulated calcein was used as a measure of the integrity of the liposomes. Plain liposomes were found to be more stable compared with C60-loaded (PC) liposomes, suggesting that C60 ruptures the liposome membrane. Toxicity studies of C60 in liposomes were carried out on cultured cells [rodent fibroblasts (3T3)] to assess further their toxicity. The results suggest that fullerene cytotoxic effect was reduced significantly after its incorporation into the liposomal bilayer after 24 h of incubation with the rodent fibroblasts (3T3). Finally, energy minimization studies were employed to underpin the experimental observations. The theoretical calculations show that low concentration of fullerene molecules present in the membrane had no effect on the membrane integrity; however, at high concentrations of fullerenes significant enlargement of the surface area is observed, supporting the experimental finding