19 research outputs found
Election Frequency and Voter Turnout
In recent decades, liberal democracies have considerably expanded the scope for citizen participation, calling their citizens to vote in a growing number of popular votes. This research investigates the effects of the rising election frequency on electoral participation. It expands on the voting calculus and theorizes which, when, and how past votes affect current voter turnout. We argue that all election types contribute to a common factor of election frequency, whose high values depress turnout and reduce the effectiveness of party mobilization even in the most important elections. We find support for the new theory using an original database of all significant elections and referendums held in 22 European democracies between 1939 and 2019, two natural experiments, and survey data from the Comparative Study of Electoral Systems. Our findings shed light on contemporary participation trends and have major implications for democratic citizenship and democratic institutional engineering
Bio-Sensing of Cadmium(II) Ions Using Staphylococcus aureusâ
Cadmium, as a hazardous pollutant commonly present in the living environment, represents an important risk to human health due to its undesirable effects (oxidative stress, changes in activities of many enzymes, interactions with biomolecules including DNA and RNA) and consequent potential risk, making its detection very important. New and unique technological and biotechnological approaches for solving this problems are intensely sought. In this study, we used the commonly occurring potential pathogenic microorganism Staphylococcus aureus for the determination of markers which could be used for sensing of cadmium(II) ions. We were focused on monitoring the effects of different cadmium(II) ion concentrations (0, 1.25, 2.5, 5, 10, 15, 25 and 50 ÎŒg mLâ1) on the growth and energetic metabolism of Staphylococcus aureus. Highly significant changes have been detected in the metabolism of thiol compoundsâspecifically the protein metallothionein (0.79â26.82 mmol/mg of protein), the enzyme glutathione S-transferase (190â5,827 ÎŒmol/min/mg of protein), and sulfhydryl groups (9.6â274.3 ÎŒmol cysteine/mg of protein). The ratio of reduced and oxidized glutathione indicated marked oxidative stress. In addition, dramatic changes in urease activity, which is connected with resistance of bacteria, were determined. Further, the effects of cadmium(II) ions on the metabolic pathways of arginine, ÎČ-glucosidase, phosphatase, N-acetyl ÎČ-d-glucosamine, sucrose, trehalose, mannitol, maltose, lactose, fructose and total proteins were demonstrated. A metabolomic profile of Staphylococcus aureus under cadmium(II) ion treatment conditions was completed seeking data about the possibility of cadmium(II) ion accumulation in cells. The results demonstrate potential in the application of microorganisms as modern biosensor systems based on biological components
Density, porosity and magnetic susceptibility of the KoĆĄice meteorite shower and homogeneity of its parent meteoroid
Bulk and grain density, porosity, and magnetic susceptibility of 67 individuals of KoĆĄice H chondrite fall were measured. The mean bulk and grain densities were determined to be 3.43 g/cm3 with standard deviation (s.d.) of 0.11 g/cm3 and 3.79 g/cm3 with s.d. 0.07 g/cm3, respectively. Porosity is in the range from 4.2 to 16.1%. The logarithm of the apparent magnetic susceptibility (in 10â9 m3/kg) shows narrow distribution from 5.17 to 5.49 with mean value at 5.35 with s.d. 0.08. These results indicate that all studied KoĆĄice meteorites are of the same composition down to âŒg scale without presence of foreign (non-H) clasts and are similar to other H chondrites. KoĆĄice is thus a homogeneous meteorite fall derived from a homogenous meteoroid.Peer reviewe
Bio-Sensing of Cadmium(II) Ions Using Staphylococcus aureusâ
Cadmium, as a hazardous pollutant commonly present in the living environment, represents an important risk to human health due to its undesirable effects (oxidative stress, changes in activities of many enzymes, interactions with biomolecules including DNA and RNA) and consequent potential risk, making its detection very important. New and unique technological and biotechnological approaches for solving this problems are intensely sought. In this study, we used the commonly occurring potential pathogenic microorganism Staphylococcus aureus for the determination of markers which could be used for sensing of cadmium(II) ions. We were focused on monitoring the effects of different cadmium(II) ion concentrations (0, 1.25, 2.5, 5, 10, 15, 25 and 50 ÎŒg mLâ1) on the growth and energetic metabolism of Staphylococcus aureus. Highly significant changes have been detected in the metabolism of thiol compoundsâspecifically the protein metallothionein (0.79â26.82 mmol/mg of protein), the enzyme glutathione S-transferase (190â5,827 ÎŒmol/min/mg of protein), and sulfhydryl groups (9.6â274.3 ÎŒmol cysteine/mg of protein). The ratio of reduced and oxidized glutathione indicated marked oxidative stress. In addition, dramatic changes in urease activity, which is connected with resistance of bacteria, were determined. Further, the effects of cadmium(II) ions on the metabolic pathways of arginine, ÎČ-glucosidase, phosphatase, N-acetyl ÎČ-d-glucosamine, sucrose, trehalose, mannitol, maltose, lactose, fructose and total proteins were demonstrated. A metabolomic profile of Staphylococcus aureus under cadmium(II) ion treatment conditions was completed seeking data about the possibility of cadmium(II) ion accumulation in cells. The results demonstrate potential in the application of microorganisms as modern biosensor systems based on biological components
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Attitudes Towards Immigration in Western and Central-Eastern Europe: A Comparative Analysis
This dissertation studies the puzzling divergence in immigration attitudes between Western and Central-Eastern Europe (CEE). While immigration attitudes in the West liberalised, they became increasingly conservative in the East. The gap in the willingness to accept at least some immigrants between the two regions drastically widened from ten percentage points in 2010 to more than thirty points in 2018. This gap emerged suddenly after decades of attitudinal convergence between the two regions. Its rapidity and timing question the conventional wisdom attributing anti-immigration attitudes in CEE to communist legacies and socialisation processes. Furthermore, it challenges some of the most prominent theories on cross-country variation in immigration attitudes - economic competition and group threat - as the deterioration of immigration attitudes coincided with a period of sustained economic growth in CEE and low immigration in contrast to Western Europe. To address this puzzle, this dissertation develops a new general theoretical framework explaining aggregate change in attitudes. It identifies five main groups of factors and spells out the concrete mechanisms through which these factors can contribute to country-level change in immigration attitudes. Subsequently, the empirical chapters systematically examine each mechanism, using data from 28 European countries. They propose several original indicators and estimation techniques and apply a variety of research designs. The employed methods include spatial analysis, generalised additive models, and estimated dependent variable models with feasible generalised least squares estimators to overcome several methodological issues and analytical limitations. The analyses draw on a range of data including *inter alia* cross-sectional surveys; geo-localised panel surveys; fine-grained contextual data; and several original datasets the most important of which is a survey experiment using a representative sample of almost 5,000 respondents in Western and Eastern regions of Germany. The results refute the conventional wisdom that attributes the anti-immigration sentiment in CEE to socialisation and emigration. Instead, they demonstrate that individualsâ immigration attitudes are malleable by migratory experience, spatial exposure to foreigners, and cues from political parties and fellow citizens. This dissertation links the sudden and rapid drop in immigration attitudes in most of the CEE region to the electoral strategy of mainstream parties. The results have implications for our understanding of attitude formation and change. They suggest that individualsâ political attitudes are not given in absolute terms. Rather, individuals may adopt positions relative to a reference, which, if changing, may lead to major attitudinal shifts
El Lenguaje de la publicidad en la prensa.
Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi
The Kremlin strikes back:Russiaâs renewed penetration of Central and Eastern Europe
Infiltration of an opposition demonstration, inciting the demonstrators to storm the countryâs parliament, then having mercenaries disguised as police massacre them, while simultaneously assassinating the countryâs long-serving Prime Minister. (First paragraph
Hydrogen Sulfide Donor Protects Porcine Oocytes against Aging and Improves the Developmental Potential of Aged Porcine Oocytes
<div><p>Porcine oocytes that have matured in in vitro conditions undergo the process of aging during prolonged cultivation, which is manifested by spontaneous parthenogenetic activation, lysis or fragmentation of aged oocytes. This study focused on the role of hydrogen sulfide (H<sub>2</sub>S) in the process of porcine oocyte aging. H<sub>2</sub>S is a gaseous signaling molecule and is produced endogenously by the enzymes cystathionine-ÎČ-synthase (CBS), cystathionine-Îł-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (MPST). We demonstrated that H<sub>2</sub>S-producing enzymes are active in porcine oocytes and that a statistically significant decline in endogenous H<sub>2</sub>S production occurs during the first day of aging. Inhibition of these enzymes accelerates signs of aging in oocytes and significantly increases the ratio of fragmented oocytes. The presence of exogenous H<sub>2</sub>S from a donor (Na<sub>2</sub>S.9H<sub>2</sub>O) significantly suppressed the manifestations of aging, reversed the effects of inhibitors and resulted in the complete suppression of oocyte fragmentation. Cultivation of aging oocytes in the presence of H<sub>2</sub>S donor positively affected their subsequent embryonic development following parthenogenetic activation. Although no unambiguous effects of exogenous H<sub>2</sub>S on MPF and MAPK activities were detected and the intracellular mechanism underlying H<sub>2</sub>S activity remains unclear, our study clearly demonstrates the role of H<sub>2</sub>S in the regulation of porcine oocyte aging.</p></div
Parthenogenetic activation of oocytes aged under the effect of the H<sub>2</sub>S donor.
<p>At Oocytes were cultivated 48 hours to the metaphase II and then divided into 4 groups (see table). Control group (MII) was parthenogenetically activated immediately (without any exposure to prolonged cultivation). Other groups were exposed to prolonged cultivation (aging) for 24 hours in modified M199 medium supplemented with a H2S donor (Na<sub>2</sub>S.9H<sub>2</sub>O; 0ÎŒM, 150ÎŒM, and 300ÎŒM) and then parthenogenetically activated with calcium ionophore (25ÎŒM, 5 min) combined with 6-dimethyl aminopurine (2mM, 2 h). Subsequently, oocytes were cultured in NCSU 23 medium for the following 24 hours.</p><p><sup>a,b,c</sup> Statistically significant differences in the ratio of activated oocytes between individual treatments (in columns) are indicated with different superscripts (P<0.05).</p><p>Parthenogenetic activation of oocytes aged under the effect of the H<sub>2</sub>S donor.</p