43 research outputs found

    Pension reform and capital market development in Central and Eastern European countries

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    The paper provides new empirical evidence for the connection between pension reform and capital market development using a sample of ten Central and Eastern European countries. Using a single equation Error Correction Model, the results confirm the existence of a strong positive short-term effect, as well as a lower magnitude positive long-term effect of the pension funds’ assets on the market capitalisation

    Optimizarea extracţiei compuşilor polifenolici din tescovina strugurilor negri

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    Grape pomace represent the main by-product of wine industry containing polyphenolic compounds with antioxidant and antibacterial activity. The aim of our study was to optimize their extraction using different organic solvents with different concentrations and different temperatures of extraction.The material used for extraction was grape pomace from three red varieties. As solvents, were used aqueous solutions from: ethanol, citric acid, acetone, sodium sulfite and glycerol, with different concentrations. The experimented temperatures for extraction were: 30, 60 and 90 C and the time of extraction was two hours for all the solvents. The best extraction was registered in case of acetone and ethanol. The nature of solvents influenced the proportion between the different classes of polyphenolic compounds extracted. The increasing temperature of the extraction had a positive effect on the extraction in case of all the solvents. Also, the increase of solvents concentration had a positive effect, up to a certain limit

    The Influence of Terroir on Phenolic Composition of Red Grapes

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    A rich content of phenolic compounds (anthocyans and tannins) is a fundamental technological condition for the obtaining of quality red wines - appreciated by increasing numbers of consumers, aware of the benefic health effects brought about by these biologically active compounds. The biosynthesis of phenols and their accumulation in the grape berries during ripening is influenced by a multitude of factors. In this study we focused on terroir and on the biological potential of the authorized red varieties for wines with controlled denomination of origin in four centres of three well-established viticultural regions: the Hills of Dobrogea, the Hills of Moldova, the Hills of Muntenia and Oltenia. The polyphenolic potential of the grapes was evaluated for the crop of 2015 by the standard Glories method, thus obtaining results for the total polyphenolic potential (ApH1), the extractable anthocyans potential (ApH3,2), the percentage of anthocyans extractability (%AE), the maturity of the seeds (MS) and total polyphenols (PT). By classifying the freshly harvested grapes on the basis of their phenolic potential using the statistical method of Principal Component Analysis, the studied varieties are clearly differentiated based on the viticultural terro

    Characterization of the harvest year and the quality of red wines from Valea Calugareasca depending of the technological and phenolic potential of the varieties

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    The study was conducted during 2014–2018 period in order to define the quality level of the Cabernet Sauvignon and Feteasa neagra varieties, according to the characteristics of the harvest year. The grape harvest was recorded earlier with 12 days in case of Cabernet Sauvignon and with 14 days in case of Fetească neagră variety, compared to the multiannual average. During the years of study, harvesting of grapes from the Cabernet Sauvignon variety was made between September 17 and October 6, and that of the grapes from the Feteasca neagra variety during September 17-28. The dynamics of grape ripening was very fast in the harvest year 2014, fast in the years 2015 and 2016, slow in 2017 and 2018. In the 2014 harvest year for the Cabernet Sauvignon variety, the phenolic maturity of the grapes was assessed as good for all determined analytical parameters. Grapes from the Cabernet Sauvignon variety are well formed, with a percentage of normally developed berries, with the skin of the grapes in a high proportion, high in anthocyanins; smallmedium grains, thick skin of the grapes. Cabernet Sauvignon wine was appreciated, compared to the average of 1990- 1999, with a very good alcoholic concentration of 12.6% vol. alc. in 2016 and 12.8% vol alc. in the years 2017 and 2018. The wine from the Feteasca neagra variety was appreciated as being extractive, with a high alcohol concentration of over 13% vol. alc., with a medium acidity, intensely colored

    A robust prognostic signature for hormone-positive node-negative breast cancer

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    BACKGROUND: Systemic chemotherapy in the adjuvant setting can cure breast cancer in some patients that would otherwise recur with incurable, metastatic disease. However, since only a fraction of patients would have recurrence after surgery alone, the challenge is to stratify high-risk patients (who stand to benefit from systemic chemotherapy) from low-risk patients (who can safely be spared treatment related toxicities and costs). METHODS: We focus here on risk stratification in node-negative, ER-positive, HER2-negative breast cancer. We use a large database of publicly available microarray datasets to build a random forests classifier and develop a robust multi-gene mRNA transcription-based predictor of relapse free survival at 10 years, which we call the Random Forests Relapse Score (RFRS). Performance was assessed by internal cross-validation, multiple independent data sets, and comparison to existing algorithms using receiver-operating characteristic and Kaplan-Meier survival analysis. Internal redundancy of features was determined using k-means clustering to define optimal signatures with smaller numbers of primary genes, each with multiple alternates. RESULTS: Internal OOB cross-validation for the initial (full-gene-set) model on training data reported an ROC AUC of 0.704, which was comparable to or better than those reported previously or obtained by applying existing methods to our dataset. Three risk groups with probability cutoffs for low, intermediate, and high-risk were defined. Survival analysis determined a highly significant difference in relapse rate between these risk groups. Validation of the models against independent test datasets showed highly similar results. Smaller 17-gene and 8-gene optimized models were also developed with minimal reduction in performance. Furthermore, the signature was shown to be almost equally effective on both hormone-treated and untreated patients. CONCLUSIONS: RFRS allows flexibility in both the number and identity of genes utilized from thousands to as few as 17 or eight genes, each with multiple alternatives. The RFRS reports a probability score strongly correlated with risk of relapse. This score could therefore be used to assign systemic chemotherapy specifically to those high-risk patients most likely to benefit from further treatment

    Coverage-controlled polymorphism of H-bonded networks on Au(111)

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    We report on the self-assembly of a conformational flexible organic compound on Au(111) using scanning tunneling microscopy and low-energy electron diffraction measurements. We observed different conformers of the compound upon adsorption on the reconstructed Au(111) surface. Increasing the molecular coverage enhanced the lateral pressure, that is, parallel to the surface, favoring a coverage-controlled transition from a supramolecular network displaying only one molecular organization, into a polymorphic array with two coexisting arrangements. Our results give insights into the role of substrate-induced conformational changes on the formation of polymorphic supramolecular networks

    Effect of Pretreatment Method on the Nanostructure and Performance of Supported Co Catalysts in Fischer−Tropsch Synthesis

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    ABSTRACT: Understanding precursor transformation to active catalysts is crucial to heterogeneous Fischer−Tropsch (FT) catalysis directed toward production of hydrocarbons for transportation fuels. Despite considerable literature on FT catalysis, the effect of pretreatment of supported cobalt catalysts on cobalt dispersion, dynamic atomic structure, and the activity of the catalysts is not well understood. Here we present systematic studies into the formation of active catalyst phases in supported Co catalyst precursors in FT catalysis using in situ environmental (scanning) transmission electron microscopy (E(S)TEM) with single-atom resolution under controlled reaction environments for in situ visualization, imaging, and analysis of reacting atomic species in real time, EXAFS, XAS, DRIFTS analyses, and catalytic activity measurements. We have synthesized and analyzed dried reduced (D) and dried calcined reduced (DC) Co real catalysts on reducible and nonreducible supports, such as SiO2, Al2O3, TiO2, and ZrO2. Comparisons of dynamic in situ atomic structural observations of reacting single atoms, atomic clusters, and nanoparticles of Co and DRIFTS, XAS, EXAFS, and catalytic activity data of the D and DC samples reveal in most cases better dispersion in the D samples, leading to a larger number of low-coordination Co0 sites and a higher number of active sites for CO adsorption. The experimental findings on the degree of reduction of D and 27 DC catalysts on reducible and nonreducible supports and correlations between hexagonal (hcp) Co sites and the activity of the catalysts generate structural insights into the catalyst dynamics, important to the development of efficient FT catalysts

    Modeling precision treatment of breast cancer

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    Background: First-generation molecular profiles for human breast cancers have enabled the identification of features that can predict therapeutic response; however, little is known about how the various data types can best be combined to yield optimal predictors. Collections of breast cancer cell lines mirror many aspects of breast cancer molecular pathobiology, and measurements of their omic and biological therapeutic responses are well-suited for development of strategies to identify the most predictive molecular feature sets. Results: We used least squares-support vector machines and random forest algorithms to identify molecular features associated with responses of a collection of 70 breast cancer cell lines to 90 experimental or approved therapeutic agents. The datasets analyzed included measurements of copy number aberrations, mutations, gene and isoform expression, promoter methylation and protein expression. Transcriptional subtype contributed strongly to response predictors for 25% of compounds, and adding other molecular data types improved prediction for 65%. No single molecular dataset consistently out-performed the others, suggesting that therapeutic response is mediated at multiple levels in the genome. Response predictors were developed and applied to TCGA data, and were found to be present in subsets of those patient samples. Conclusions: These results suggest that matching patients to treatments based on transcriptional subtype will improve response rates, and inclusion of additional features from other profiling data types may provide additional benefit. Further, we suggest a systems biology strategy for guiding clinical trials so that patient cohorts most likely to respond to new therapies may be more efficiently identified

    Expression variability of co-regulated genes differentiates Saccharomyces cerevisiae strains

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    Background: Saccharomyces cerevisiae (Baker’s yeast) is found in diverse ecological niches and is characterized by high adaptive potential under challenging environments. In spite of recent advances on the study of yeast genome diversity, little is known about the underlying gene expression plasticity. In order to shed new light onto this biological question, we have compared transcriptome profiles of five environmental isolates, clinical and laboratorial strains at different time points of fermentation in synthetic must medium, during exponential and stationary growth phases. Results: Our data unveiled diversity in both intensity and timing of gene expression. Genes involved in glucose metabolism and in the stress response elicited during fermentation were among the most variable. This gene expression diversity increased at the onset of stationary phase (diauxic shift). Environmental isolates showed lower average transcript abundance of genes involved in the stress response, assimilation of nitrogen and vitamins, and sulphur metabolism, than other strains. Nitrogen metabolism genes showed significant variation in expression among the environmental isolates. Conclusions: Wild type yeast strains respond differentially to the stress imposed by nutrient depletion, ethanol accumulation and cell density increase, during fermentation of glucose in synthetic must medium. Our results support previous data showing that gene expression variability is a source of phenotypic diversity among closely related organisms.Fundação para a Ciência e TecnologiaThe authors wish to thank Adega Cooperativa da Bairrada, Cantanhede, Portugal, for providing the commercial strains
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