Productive Performance and Technology Gaps using a Bayesian Metafrontier Production Function: A cross-country comparison.

Growth theory argues on the role of heterogeneity that can lead to multiple regimes examining countries’ performance. A meta-production stochastic function under a Bayesian perspective has been developed to estimate technical efficiencies across countries over a time period. The metafrontier model is used to highlight heterogeneity among cluster of countries revealing catch up phenomena. The estimation procedure relies on the solution of an optimization problem and on the concept of the upper orthant order of two multinormal random variables. The proposed models are applied in a real dataset consisting of 109 countries for a 20-year period from 1995-2014. The productive performance differential and the associated technology gaps were investigated using two distinct frontiers (OECD vs non-OECD countries). Empirical results reveal that heterogeneity indeed plays a significant and distinctive role in determining technological gaps

Productive Performance and Technology Gaps using a Bayesian Metafrontier Production Function: A cross-country comparison.

Growth theory argues on the role of heterogeneity that can lead to multiple regimes examining countries’ performance. A meta-production stochastic function under a Bayesian perspective has been developed to estimate technical efficiencies across countries over a time period. The metafrontier model is used to highlight heterogeneity among cluster of countries revealing catch up phenomena. The estimation procedure relies on the solution of an optimization problem and on the concept of the upper orthant order of two multinormal random variables. The proposed models are applied in a real dataset consisting of 109 countries for a 20-year period from 1995-2014. The productive performance differential and the associated technology gaps were investigated using two distinct frontiers (OECD vs non-OECD countries). Empirical results reveal that heterogeneity indeed plays a significant and distinctive role in determining technological gaps

Subcutaneous emphysema, pneumomediastinum and pneumoperitoneum after unsuccessful ERCP: a case report

Background: The presence of subcutaneous emphysema, pneumomediastinum and pneumoperitoneum simultaneously is a rare complication of upper gastrointestinal endoscopy that usually indicates free perforation to the peritoneal cavity or the retroperitoneal space. Case presentation: We report an unusual case of a self-limited subcutaneous emphysema, pneumomediastinum and pneumoperitoneum following an unsuccessful ERCP for removal of a common bile duct stone. Conclusion: There was no radiological evidence of peritoneal or retroperitoneal perforation. This complication is distinct from pneumomediastinum and pneumoperitoneum due to perforation, and must be recognized, because it is benign and needs no surgical or radiological intervention. Background Endoscopic retrograde cholangiopancreatography (ERCP) is a standard invasive technique for revealing and man-agement of a wide spectrum of distal bile duct disorders. The rate of significant complications is very low if it isn'

Cell-Type-Dependent Thyroid Hormone Effects on Glioma Tumor Cell Lines

Purpose. The present study investigated the potential effects of long-term T3 treatment on glioma tumor cell lines. Thyroid hormone action on cell growth, differentiation and survival during development may be of therapeutic relevance Methods and Results 1321N1 cell line, an astrocytoma grade II, and U87MG, a glioblastoma grade IV, were exposed for 2 and 4 days in medium deprived of T3 and in medium containing 1 nM T3. T3 promoted re-differentiation in both cell lines. However, T3 increased cell proliferation in 1321N1 (2 days) which declined thereafter (4 days) while in U87MG resulted in suppression of cell proliferation. At the molecular level, a 2.9 fold increase in the expression of TRα1 receptor was observed in U87MG versus 1321N1, P < 0.05. TRβ1 receptor was undetectable. These changes corresponded to a distinct pattern of T3-induced kinase signaling activation; T3 had no effect on ERK activation in both cell lines but significantly increased phospho-Akt levels in 1321N1. Conclusion. In conclusion, T3 can re-differentiate glioma tumor cells, whereas its effect on cell proliferation appears to be dependent on the type of tumor cell line with aggressive tumors being more sensitive to T3. TRα1 receptor may, at least in part, be implicated in this response

Herding dynamics in exchange groups: Evidence from Euronext

This study investigates in the context of the Euronext, whether joining an exchange group affects herding in the group's member-markets and if this effect persists when accounting for various domestic and international market states, the dynamics of the group's member-markets and the outbreak of financial crises. We find that herding is significant post-merger in all four constituent equity markets (Belgium, France, the Netherlands and Portugal) of the Euronext, with herding in Portugal being significant (yet less strong) pre-merger as well. These results are robust when controlling for various domestic and international market states, as well as the dynamics of the group's markets. The period following the outbreak of the euro-zone sovereign debt crisis produces significant herding in Belgium, the Netherlands and Portugal, with this herding being motivated by the dynamics of the group's two largest markets (France and the Netherlands)

Modeling of bulk kerogen porosity: Methods for control and characterization

Shale gas is an unconventional source of energy, which has attracted a lot of attention during the last years. Kerogen is a prime constituent of shale formations and plays a crucial role in shale gas technology. Significant experimental effort in the study of shales and kerogen has produced a broad diversity of experimentally determined structural and thermodynamic properties even for samples of the same well. Moreover, proposed methods reported in the literature for constructing realistic bulk kerogen configurations have not been thoroughly investigated. One of the most important characteristics of kerogens is their porosity, due to its direct connection with their transport properties and its potential as discriminating and classifying metric between samples. In this study, molecular dynamics (MD) simulations are used to study the porosity of model kerogens. The porosity is controlled effectively with systematic variations of the number and the size of dummy LJ particles that are used during the construction of system’s configuration. The porosity of each sample is characterized with a newly proposed algorithm for analyzing the free space of amorphous materials. It is found that, with moderately sized configurations, it is possible to construct percolated pores of interest in the shale gas industry

Structural dynamics in the evolution of a bilobed protein scaffold

Novel biophysical tools allow the structural dynamics of proteins and the regulation of such dynamics by binding partners to be explored in unprecedented detail. Although this has provided critical insights into protein function, the means by which structural dynamics direct protein evolution remain poorly understood. Here, we investigated how proteins with a bilobed structure, composed of two related domains from the periplasmic-binding protein–like II domain family, have undergone divergent evolution, leading to adaptation of their structural dynamics. We performed a structural analysis on ∼600 bilobed proteins with a common primordial structural core, which we complemented with biophysical studies to explore the structural dynamics of selected examples by single-molecule Förster resonance energy transfer and Hydrogen–Deuterium exchange mass spectrometry. We show that evolutionary modifications of the structural core, largely at its termini, enable distinct structural dynamics, allowing the diversification of these proteins into transcription factors, enzymes, and extracytoplasmic transport-related proteins. Structural embellishments of the core created interdomain interactions that stabilized structural states, reshaping the active site geometry, and ultimately altered substrate specificity. Our findings reveal an as-yet-unrecognized mechanism for the emergence of functional promiscuity during long periods of evolution and are applicable to a large number of domain architectures

Potential impacts of climate change on flow regime and fish habitat in mountain rivers of the southwestern Balkans

The climate change in the Mediterranean area is expected to have significant impacts on the aquatic ecosystems and particular in the mountain rivers and streams that often host important species such as the Salmo farioides, Karaman 1938. These impacts will most possibly affect the habitat availability for various aquatic species resulting to an essential alteration of the water requirements, either for dams or other water abstractions, in order to maintain the essential levels of ecological flow for the rivers. The main scope of this study was to assess potential climate change impacts on the hydrological patterns and typical biota for a south-western Balkan mountain river, the Acheloos. The altered flow regimes under different emission scenarios of the Intergovernmental Panel on Climate Change (IPCC) were estimated using a hydrologicalmodel and based on regional climate simulations over the study area. The Indicators of Hydrologic Alteration (IHA) methodology was then used to assess the potential streamflow alterations in the studied river due to predicted climate change conditions. A fish habitat simulation method integrating univariate habitat suitability curves and hydraulic modeling techniques were used to assess the impacts on the relationships between the aquatic biota and hydrological status utilizing a sentinel species, the West Balkan trout. The most prominent effects of the climate change scenarios depict severe flow reductions that are likely to occur especially during the summer flows, changing the duration and depressing the magnitude of the natural low flow conditions. Weighted Usable Area-flow curves indicated the limitation of suitable habitat for the native trout. Finally, this preliminary application highlighted the potential of science-based hydrological and habitat simulation approaches that are relevant to both biological quality elements (fish) and current EUWater policy to serve as efficient tools for the estimation of possible climate change impacts on the south-western Balkan river ecosystems.This study was supported by the ECOFLOW project funded by the Hellenic General Secretariat of Research and Technology in the framework of the NSRF 2007-2013. The W. B. trout data collection was partially funded by the Spanish Ministry of Economy and Competitiveness with the project SCARCE (Consolider-Ingenio 2010 CSD2009-00065).Papadaki, C.; Soulis, K.; Muñoz Mas, R.; Martinez-Capel, F.; Zogaris, S.; Ntoanidis, L.; Dimitriou, E. (2016). Potential impacts of climate change on flow regime and fish habitat in mountain rivers of the southwestern Balkans. Science of the Total Environment. 540:418-428. https://doi.org/10.1016/j.scitotenv.2015.06.134S41842854