914 resultados para radiosorgenti,AGN,BL Lacs,radiogalassie,core dominance
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Commercial samples of Magnetite with size ranging from 25–30nm were coated with polyaniline by using radio frequency plasma polymerization to achieve a core shell structure of magnetic nanoparticle (core)–Polyaniline (shell). High resolution transmission electron microscopy images confirm the core shell architecture of polyaniline coated iron oxide. The dielectric properties of the material were studied before and after plasma treatment. The polymer coated magnetite particles exhibited a large dielectric permittivity with respect to uncoated samples. The dielectric behavior was modeled using a Maxwell–Wagner capacitor model. A plausible mechanism for the enhancement of dielectric permittivity is proposed
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This article present the result from a study of two sediment cores collected from the environmentally distinct zones of CES. Accumulation status of five toxic metals: Cadmium (Cd), Chromium (Cr), Cobalt (Co), Copper (Cu) and Lead (Pb) were analyzed. Besides texture and CHNS were determined to understand the composition of the sediment. Enrichment Factor (EF) and Anthropogenic Factor (AF) were used to differentiate the typical metal sources. Metal enrichment in the cores revealed heavy load at the northern (NS1 ) region compared with the southern zone (SS1). Elevation of metal content in core NS1 showed the industrial input. Statistical analyses were employed to understand the origin of metals in the sediment samples. Principal Component Analysis (PCA) distinguishes the two zones with different metal accumulation capacity: highest at NS1 and lowest at SS1. Correlation analysis revealed positive significant relation only in core NS1, adhering to the exposition of the intensified industrial pollution
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Southern Ocean (SO) is the fourth largest Ocean comprising the southern portions of the Atlantic Ocean, Indian Ocean and Pacific Ocean. Sediment core sample (660 34’S and 580 40’E)was collected onboard O.R.V Sagar Nidhi from January to March 2010 in the Fourth Southern Ocean expedition cruise launched by the National Centre for Antarctic and Ocean Research, Goa . Sedimentary records from this area reveal the sensitivity and climatic variability’s of the region over a large time scale. Organic matter (OM) and textural behaviour of the samples were analyzed and processed concurrently. Distribution of OM, Total Organic Carbon (TOC), Protein, Lipid and Carbohydrate along with the trace metal was highlighted. Textural variation was in the array of Sand >Clay >Silt. Sand content ranges from 30.29% to 80.11%. The order of relative distribution of OM was Lipid >Protein > TOC > Carbohydrate. The average concentrations of TOC, Protein, Lipid and Carbohydrate were 2.2 mg/g, 1.2 mg/g, 3.3 mg/g and 1.1mg/g respectively. Protein to carbohydrate ratio and lipid to carbohydrate ratio were also encountered to understand the respective freshness and nutritional quality of the sediments. Trace metal distribution showed the average concentration was maximum for Mn and minimum for Co.
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Distribution of toxic metal in the sediment core is an important area of research for environmental impact studies. Sediment cores were collected from two prominent region(C1 and C2) of CE and subjected to geochemical analysis to determine distribution of toxic metals (Cd, Co, Cr, Cu and Pb ), texture characteristics, total organic carbon (TOC) and CHNS. Statistical analysis was done to understand the interrelationship between the components. In the studied cores, metal contamination level was identified for Pb, Cu; Cr, in C1 and C2 respectively. The metal distribution depends on the granulometric factor, geogenic mineral components and anthropogenic input. Correlation analysis (CA) and Principal component(PCA) analysis also support these results
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Geochemical composition is a set of data for predicting the climatic condition existing in an ecosystem. Both the surficial and core sediment geochemistry are helpful in monitoring, assessing and evaluating the marine environment. The aim of the research work is to assess the relationship between the biogeochemical constituents in the Cochin Estuarine System (CES), their modifications after a long period of anoxia and also to identify the various processes which control the sediment composition in this region, through a multivariate statistical approach. Therefore the study of present core sediment geochemistry has a critical role in unraveling the benchmark of their characterization. Sediment cores from four prominent zones of CES were examined for various biogeochemical aspects. The results have served as rejuvenating records for the prediction of core sediment status prevailing in the CES
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Geochemical composition is a set of data for predicting the climatic condition existing in an ecosystem. Both the surficial and core sediment geochemistry are helpful in monitoring, assessing and evaluating the marine environment. The aim of the research work is to assess the relationship between the biogeochemical constituents in the Cochin Estuarine System (CES), their modifications after a long period of anoxia and also to identify the various processes which control the sediment composition in this region, through a multivariate statistical approach. Therefore the study of present core sediment geochemistry has a critical role in unraveling the benchmark of their characterization. Sediment cores from four prominent zones of CES were examined for various biogeochemical aspects. The results have served as rejuvenating records for the prediction of core sediment status prevailing in the CES
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Cochin University of Science And Technology
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The working paper’s main objective is to explore the extent to which non-compliance to international labor rights is caused by global competition. From the perspective of institutional economics, compliance with core labor rights is beneficial for sustainable development. Nonetheless, violations of these rights occur on a massive scale. The violators usually blame competitive pressures. A number of studies have come to the conclusion that non-compliance does not provide for a competitive edge, thereby denying any economic rationale for non-compliance. While we sympathize with this conclusion, we find that these studies suffer from faulty assumptions in the design of their regression analyses. The assumption of perfect markets devoid of power relations is particularly unrealistic. While workers' rights promise long-term benefits, they may incur short-term production cost increases. On the supply side, the production sites with the highest amount of labor rights violations are characterized by a near perfect competitive situation. The demand side, however, is dominated by an oligopoly of brand name companies and large retailers. Facing a large pool of suppliers, these companies enjoy more bargaining power. Developing countries, the hosts to most of these suppliers, are therefore limited in their ability to raise labor standards on their own. This competitive situation, however, is the very reason why labor rights have to be negotiated internationally. Our exploration starts with an outline of the institutionalist argument of the benefits of core labor rights. Second, we briefly examine some cross-country empirical studies on the impact of trade liberalization (as a proxy for competitive pressures). Third, we develop our own argument which differentiates the impact of trade liberalization along the axes of labor- and capital-intensive production as well as low and medium skill production. Finally, we present evidence from a study on the impact of trade liberalization in Indonesia on the garment industry as an example of a low skill, laborintensive industry on the one hand, and the automobile as an example for a medium skill, capital-intensive industry on the other hand. Because the garment industry’s workforce consists mainly of women, we also discuss the gender dimension of trade liberalization.
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We have discovered that the current protocols to assemble Au nanoparticles based on DNA hybridization do not work well with the small metal nanoparticles (e.g. 5 nm Au, 3.6 nm Pt and 3.2 nm Ru particles). Further investigations revealed the presence of strong interaction between the oligonucleotide backbone and the surface of the small metal nanoparticles. The oligonucleotides in this case are recumbent on the particle surface and are therefore not optimally oriented for hybridization. The nonspecific adsorption of oligonucleotides on small metal nanoparticles must be overcome before DNA hybridization can be accepted as a general assembly method. Two methods have been suggested as possible solutions to this problem. One is based on the use of stabilizer molecules which compete with the oligonucleotides for adsorption on the metal nanoparticle surface. Unfortunately, the reported success of this approach in small Au nanoparticles (using K₂BSPP) and Au films (using 6-mercapto-1-hexanol) could not be extended to the assembly of Pt and Ru nanoparticles by DNA hybridization. The second approach is to simply use larger metal particles. Indeed most reports on the DNA hybridization induced assembly of Au nanoparticles have made use of relatively large particles (>10 nm), hinting at a weaker non-specific interaction between the oligonucleotides and large Au nanoparticles. However, most current methods of nanoparticle synthesis are optimized to produce metal nanoparticles only within a narrow size range. We find that core-shell nanoparticles formed by the seeded growth method may be used to artificially enlarge the size of the metal particles to reduce the nonspecific binding of oligonucleotides. We demonstrate herein a core-shell assisted growth method to assemble Pt and Ru nanoparticles by DNA hybridization. This method involves firstly synthesizing approximately 16 nm core-shell Ag-Pt and 21 nm core-shell Au-Ru nanoparticles from 9.6 nm Ag seeds and 17.2 nm Au seeds respectively by the seed-mediated growth method. The core-shell nanoparticles were then functionalized by complementary thiolated oligonucleotides followed by aging in 0.2 M PBS buffer for 6 hours. The DNA hybridization induced bimetallic assembly of Pt and Ru nanoparticles could then be carried out in 0.3 M PBS buffer for 10 hours.
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Resumen tomado de la publicaci??n. Resumen tambi??n en ingl??s
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El propósito de la presente investigación es evaluar la incidencia regional de las iniciativas chinas a favor de la gestión del agua del Río Mekong como elementos que contribuyen en la construcción de la percepción favorable para el gigante asiático. Producto del conjunto de reformas aplicadas desde 1978, China fue objeto de un crecimiento económico exponencial que algunos académicos denominan milagroso; sin embargo, dicho proceso involucró un impacto negativo sobre el medio ambiente y en particular sobre el agua del Estado. El deterioro ambiental chino implicó, por un lado, el desarrollo de medidas internas que pretenden reversar los efectos descritos en el marco de las diferentes cumbres mundiales sobre medio ambiente y por otro, la participación en iniciativas de carácter subregional que denotan cierto grado de pro-actividad del gigante asiático en materia ambiental.
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Objetivo. Determinar la validez de apariencia y concurrente de un instrumento de evaluación de la discapacidad en personas con lesión medular crónica (SCI-DAS), basado en el core set abreviadode la CIF. Metodología. Participaron 100 personas con lesión medular de más de seis meses de evolución de cuatro ciudades colombianas, así como ocho fisioterapeutas con una experiencia profesional promedio de 6,75 años. La validez de apariencia se evaluó a través de un grupo focal y una encuesta a los observadores, se calcularon los coeficientes de variación de los ítems y los índices de pertinencia y adecuación. Mediante el coeficiente de correlación de Spearman se analizó la validez concurrente con la escala de deficiencia AIS (American SpinalInjury Association[ASIA] Impairment Scale), y la escala de discapacidad WHO-DASII. Resultados. La pertinencia y adecuación global del instrumento arrojaron una media de 4,83/5 y 4,48/5 con un coeficiente de variación de 0,03. El índice de acuerdo entre observadores para las calificaciones de buena y excelente fue de 0,96 para pertinencia y 0,86 para adecuación. La discapacidad medida con el SCI-DAS mostró correlación significativa moderada con el nivel neurológico, los índice motor y sensitivo AIS, y alta con la discapacidad medida con el WHO-DAS II (p<0,001). Se encontró correlación baja estadísticamente marginal con la escala de compromiso funcional AIS (p=0,052). Conclusiones. Se encontró en general buena validez de apariencia del instrumento SCI-DAS, así mismo se evidenció la validez concurrente del instrumento SCI-DAS con la escala de deficiencia AIS y con la Escala de Discapacidad de la OMS-WHO-DAS II.