666 research outputs found

    Overview of the Anti-Corruption Fight in Armenia

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    According to the NGO Policy Forum Armenia's estimation, Armenia lost 5.9billionin2013becauseofcorruption,andinsteadofaGDPof5.9 billion in 2013 because of corruption, and instead of a GDP of 10.5 billion in 2013, it would have had $16.4 billion, if only it had had a level of governance comparable to Botswana and Namibia. On February 19, 2015 Armenia established a new institutional structure to fight corruption led by the Prime Minister. This new setup requires the adoption of a new, third anti-corruption strategy for Armenia. The implementation of the previous two strategies and their action plans (2003-2006 and 2009-2012) have not brought substantial changes in the fight against corruption and most importantly have not increased popular trust in the effectiveness of fighting corruption. This article will examine Armenia's experience in fighting corruption, and then discuss current obstacles to success in the context of the new institutional setup

    INTERVAL EDGE COLORING OF TREES WITH STRICT RESTRICTIONS ON THE SPECTRUMS

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    An edge-coloring of a graph G with consecutive integers C1 ,..., Ct is called an interval t-coloring if all the colors are used, and the colors of edges incident to any vertex of G are distinct and form an interval of integers. A graph G is interval colorable if it has an interval t-coloring for some positive integer t. For an edge coloring a and a vertex v the set of all the colors of the incident edges of v is called the spectrum of that vertex in a and is denoted by Sa(v). We consider the case where the spectrum for each vertex v is provided S(v), and the problem is to find an edge-coloring a such that for every vertex v, Sa(v)=S(v). We provide an O(N) algorithm that finds such an edge-coloring for trees that satisfies all the restrictions. If it is impossible to have an edge-coloring that satisfies the restrictions of the spectrums the algorithm will tell that too.An edge-coloring of a graph G with consecutive integers C1 ,..., Ct is called an interval t-coloring if all the colors are used, and the colors of edges incident to any vertex of G are distinct and form an interval of integers. A graph G is interval colorable if it has an interval t-coloring for some positive integer t. For an edge coloring a and a vertex v the set of all the colors of the incident edges of v is called the spectrum of that vertex in a and is denoted by Sa(v). We consider the case where the spectrum for each vertex v is provided S(v), and the problem is to find an edge-coloring a such that for every vertex v, Sa(v)=S(v). We provide an O(N) algorithm that finds such an edge-coloring for trees that satisfies all the restrictions. If it is impossible to have an edge-coloring that satisfies the restrictions of the spectrums the algorithm will tell that too

    EDGE COLORING OF CACTUS GRAPHS WITH GIVEN SPECTRUMS

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    An edge-coloring of a graph G is a coloring of the graph edges with integers such that the colors of the edges incident to any vertex of G are distinct. For an edge coloring α and a vertex v the set of all the colors of the incident edges of v is called the spectrum of that vertex in α and is denoted by Sa(V). We consider the case where the spectrum for each vertex V is provided S(V), and the problem is to find an edge-coloring α such that for every vertex V, Sa(V) = S(V). We provide an O(N2) algorithm that inds such an edge-coloring for cactus graphs that satisfies all the restrictions. If it is impossible to have an edge-coloring hat satisfiesthe restrictions of the spectrums the algorithm will tell that too.An edge-coloring of a graph G is a coloring of the graph edges with integers such that the colors of the edges incident to any vertex of G are distinct. For an edge coloring α and a vertex v the set of all the colors of the incident edges of v is called the spectrum of that vertex in α and is denoted by Sa(V). We consider the case where the spectrum for each vertex V is provided S(V), and the problem is to find an edge-coloring α such that for every vertex V, Sa(V) = S(V). We provide an O(N2) algorithm that inds such an edge-coloring for cactus graphs that satisfies all the restrictions. If it is impossible to have an edge-coloring hat satisfiesthe restrictions of the spectrums the algorithm will tell that too

    LIST COLORING OF BLOCK GRAPHS AND COMPLETE BIPARTITE GRAPHS

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    List coloring is a vertex coloring of a graph where each vertex can be restricted to a list of allowed colors. For a given graph G and a set L(v) of colors for every vertex v, a list coloring is a function that maps every vertex v to a color in the list L(v) such that no two adjacent vertices receive the same color. It was first studied in the 1970s in independent papers by Vizing and by Erdős, Rubin, and Taylor. A block graph is a type of undirected graph in which every biconnected component (block) is a clique. A complete bipartite graph is a bipartite graph with partitions V 1, V 2 such that for every two vertices v_1∈V_1 and v_2∈V_2 there is an edge (v 1, v 2). If |V_1 |=n and |V_2 |=m it is denoted by K_(n,m). In this paper we provide a polynomial algorithm for finding a list coloring of block graphs and prove that the problem of finding a list coloring of K_(n,m) is NP-complete even if for each vertex v the length of the list is not greater than 3 (|L(v)|≤3).List coloring is a vertex coloring of a graph where each vertex can be restricted to a list of allowed colors. For a given graph G and a set L(v) of colors for every vertex v, a list coloring is a function that maps every vertex v to a color in the list L(v) such that no two adjacent vertices receive the same color. It was first studied in the 1970s in independent papers by Vizing and by Erdős, Rubin, and Taylor. A block graph is a type of undirected graph in which every biconnected component (block) is a clique. A complete bipartite graph is a bipartite graph with partitions V 1, V 2 such that for every two vertices v_1∈V_1 and v_2∈V_2 there is an edge (v 1, v 2). If |V_1 |=n and |V_2 |=m it is denoted by K_(n,m). In this paper we provide a polynomial algorithm for finding a list coloring of block graphs and prove that the problem of finding a list coloring of K_(n,m) is NP-complete even if for each vertex v the length of the list is not greater than 3 (|L(v)|≤3)

    Transformations of selected carotenoids in plasma, liver, and ocular tissues of humans and in nonprimate animal models

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    Journal ArticlePURPOSE: To determine the stereochemistry of carotenoids in human ocular tissues in comparison with plasma and liver and to elucidate the possible transformations of dietary (3R,3'R,6'R)-lutein and (3R,3'R)-zeaxanthin in the eye. Similarly, to characterize the carotenoid profiles in the eye tissues, plasma, and liver of quails and frogs to determine whether these can serve as appropriate nonprimate animal models for metabolic studies. METHODS: Configurational isomers of carotenoids and their nondietary by-products from pooled human plasma, liver, retinal pigment epithelium (RPE-choroid), ciliary body, iris, and lens were characterized and quantified by high-performance liquid chromatography (HPLC) on a chiral column. Carotenoids and their nondietary by-products in pooled extracts from quail and frog plasma, liver, retina, RPE-choroid, iris, and lens were similarly characterized and quantified. RESULTS: (3R,3'R,6'R)-lutein, (3R,3'R)-zeaxanthin, (3R,3'S; meso)-zeaxanthin, (3R,3'S,6'R)-lutein (3'-epilutein), 3-hydroxy-beta, epsilon -carotene-3'-one, and 5Z- and all-E-lycopene were detected in nearly all human ocular tissues examined. (3R,3'S; meso)-zeaxanthin was not detected in the human plasma and liver but was present in human macula, retina, and RPE-choroid. (3S,3'S)-zeaxanthin was detected in human macula in minute quantities. The carotenoid profiles in quail and frog ocular tissues were somewhat similar to those in humans, with the exception that lycopene was absent. Frog retina, plasma, and liver revealed the presence of (3S,3'S)-zeaxanthin. CONCLUSIONS: The most likely transformations of carotenoids in the human eye involve a series of oxidation-reduction and double-bond isomerization reactions. Quail and frog appear to possess the appropriate enzymes for conversion of dietary (3R,3'R,6'R)-lutein and (3R,3'R)-zeaxanthin to the same nondietary by-products observed in humans and thus may serve as excellent nonprimate animal models for metabolic studies

    Identification of lutein and zeaxanthin oxidation products in human and monkey retinas

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    Journal ArticlePURPOSE: To characterize fully all the major and minor carotenoids and their metabolites in human retina and probe for the presence of the oxidative metabolites of lutein and zeaxanthin. METHODS: Carotenoids of a composite of 58 pairs of human retinas and a monkey retina were elucidated by comparing their high-performance liquid chromatography (HPLC)-ultraviolet/visible absorption spectrophotometry (UV/Vis)-mass spectrometry (MS) profile with those of authentic standards prepared by organic synthesis. RESULTS: In addition to lutein and zeaxanthin, several oxidation products of these compounds were present in the extracts from human retina. A major carotenoid resulting from direct oxidation of lutein was identified as 3-hydroxy-beta, epsilon-caroten-3'-one. Minor carotenoids were identified as: 3'-epilutein, epsilon,epsilon-carotene-3,3'-diol, epsilon,epsilon-carotene-3,3'-dione, 3'-hydroxy-epsilon,epsilon-caroten-3-one, and 2,6-cyclolycopene-1,5-diol. Several of the geometric isomers of lutein and zeaxanthin were also detected at low concentrations. These were as follows: 9-cis-lutein, 9'-cislutein, 13-cis-lutein, 13'-cis-lutein, 9-cis-zeaxanthin, and 13-cis-zeaxanthin. Similar results were also obtained from HPLC analysis of a freshly dissected monkey retina. CONCLUSIONS: Lutein, zeaxanthin, 3'-epilutein, and 3-hydroxy-beta,epsilon-caroten-3'-one in human retina may be interconverted through a series of oxidation-reduction reactions similar to our earlier proposed metabolic transformation of these compounds in humans. The presence of the direct oxidation product of lutein and 3'-epilutein (metabolite of lutein and zeaxanthin) in human retina suggests that lutein and zeaxanthin may act as antioxidants to protect the macula against short-wavelength visible light. The proposed oxidative-reductive pathways for lutein and zeaxanthin in human retina, may therefore play an important role in prevention of age-related macular degeneration and cataracts
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