909 resultados para Stationary states and oscillations
Resumo:
The high-spin states of Pm-140 have been investigated through the reaction Te-126(F-19, 5n) at a beam energy of 90 MeV. A previous level scheme based on the 8(-) isomer has been updated with spin up to 23 (h) over bar. A total of 22 new levels and 41 new transitions were identified. Six collective bands were observed. Five of them were expanded or re-constructed, and one of them was newly identified. The systematic signature splitting and inversion of the yrast pi h(11/2)circle times vh(11/2) band in Pr and Pm odd-odd isotopes has been discussed. Based on the systematic comparison, two Delta I = 2 bands were proposed as double-decoupled bands; other two bands with strong Delta I = 1 M1 transitions inside the bands were suggested as oblate bands with gamma similar to -60 degrees; another band with large signature splitting has been proposed with oblate-triaxial deformation with gamma similar to -90 degrees. The characteristics for these bands have been discussed.
Resumo:
Three cellulose derivatives were synthesized and used as chiral stationary phases based on silica gel. The effects of adsorbances on the column numbers and stabilities have been investigated. These stationary phases exhibited high chiral recognition for various racemates. At the same time, the on-line curves of polarimeter were obtained by high performance liquid chromatography with polarimeter as on-line detector.
Resumo:
This thesis examines the tension between patent rights and the right to health and it recognizes patent rights on pharmaceutical products as one of the factors responsible for the problem of lack of access to affordable medicines in developing countries. The thesis contends that, in order to preserve their patent policy space and secure access to affordable medicines for their citizens, developing countries should incorporate a model of human rights into the design, implementation, interpretation, and enforcement of their national patent laws. The thesis provides a systematic analysis of court decisions from four key developing countries (Brazil, India, Kenya, and South Africa) and it assesses how the national courts in these countries resolve the tension between patent rights and the right to health. Essentially, this thesis demonstrates how a model of human rights can be incorporated into the adjudication of disputes involving patent rights in national courts. Focusing specifically on Brazil, the thesis equally demonstrates how policy makers and law makers at the national level can incorporate a model of human rights into the design or amendment of their national patent law. This thesis also contributes to the ongoing debate in the field of business and human rights with regard to the mechanisms that can be used to hold corporate actors accountable for their human rights responsibilities. This thesis recognizes that, while states bear the primary responsibility to respect, protect, and fulfil the right to health, corporate actors such as pharmaceutical companies also have a baseline responsibility to respect the right to health. This thesis therefore contends that pharmaceutical companies that own patent rights on pharmaceutical products can be held accountable for their right to health responsibilities at the national level through the incorporation of a model of civic participation into a country’s patent law system.
Resumo:
The presented numerical modelling for the magnetic levitation involves coupling of the electromagnetic field, liquid shape change, fluid velocities and the temperature field at every time step during the simulation in time evolution. Combination of the AC and DC magnetic fields can be used to achieve high temperature, stable levitation conditions. The oscillation frequency spectra are analysed for droplets levitated in AC and DC magnetic fields at various combinations. An electrically poorly conducting, diamagnetic droplet (e.g. water) can be stably levitated using the dia- and para-magnetic properties of the sample material in a high intensity, gradient DC field.
Resumo:
An analytical treatment of optical transmission through periodically nanosructured metal films capable of supporting surface-plasmon polaritons is presented. The optical properties of such metal films are governed by surface polariton behavior in a periodic surface structure forming a surface polaritonic crystal. Due to different configurations of the electromagnetic field of surface polariton modes, only states of even Brillouin zones are responsible for the optical transmission enhancement at normal incidence. The transmission enhancement is related to photon tunneling via resonant states of surface polariton Bloch modes in which the energy buildup takes place. Surface polariton states of at least one of the film interfaces contribute to the transmission resonance which occurs due to tunnel coupling between photons and surface polaritons on the opposite interfaces. Under double-resonance conditions, resonant tunneling between surface polariton states of both interfaces is achieved, which leads to further enhancement of the transmission efficiency. The double-resonance conditions occur not only in the case of a film in symmetric environment but can also be engineered for a film on a substrate. Light tunneling via surface polariton states can take place directly through a structured metal film and does not necessarily require holes in a film.
Resumo:
Does the World Trade Organization function to reinforce American dominance (or hegemony) of the world economy? We examine this question via an analysis of trade disputes involving the United States. This allows us to assess whether the US does better than other countries in this judicialised forum: and in so doing enhance the competitive prospects of their firms. The results are equivocal. The United States does best in the early phases of a dispute, where political power is important. It does less well as the process develops.
Resumo:
Biological activities greatly influence the formation of many soils, especially forest soils under cool humid climates. The objective of this study was to investigate the effects of vegetation and soil biota on the formation of selected soils. Field morphology, micromorphology, and carbon and organic matter analysis were determined on six Podzols (Spodosols) and two Cambisols (Inceptisols) from the eastern United States and north-east Scotland. Humification of plant material by soil fauna and fungi occurs in all organic horizons. Thick organic coatings are observed on soil peds and rock fragments from the E1 to the Bs horizon in a Haplic Podzol from Clingmans Dome Mt., TN. Thin sections reveal large accumulations of root material in different stages of decomposition in the spodic horizons of a Haplic Podzol from Whiteface Mt., NY. Organic carbon ranges from 5.4 to 8.5% in the spodic B horizons of the Whiteface Mt. Podzol. Earthworms and enchytraeids have a great effect on the structure of the surface and subsurface horizons in the Dystric Cambisols from Huntly and Clashindarroch Forests, Scotland and a Cambic Podzol from the Corrie Burn Basin, Scotland. Podzols from Speymouth Forest, Scotland (Gleyic Podzol), Cling-mans Dome Mt., and Whiteface Mt. have thick organic horizons. The Podzols from the Flatwoods in Georgia, the Pine Barrens in New Jersey, the Corrie Burn Basin, and the Cambisol from Huntly Forest have only A horizons at the surface. The Clashindarroch Forest soil has a very thin organic horizon. Warm and humid climates and sandy parent material are responsible for thick E horizons and lack of thick organic horizons in the Flatwoods (Carbic Podzol) and Pine Barrens (Ferric Podzol) soils. Earthworms and enchytraeids thrive in the Corrie Burn Basin and Huntly Forest soils due to the vegetation and the highly weathered basic parent material. The site at Clashindarroch once carried oak, and then birch forest, both of which produce a mild litter and also encourage earthworm and enchytraeids. This fauna is responsible for much mixing of the topsoil. The present conifer vegetation will eventually produce a deep litter and cause podzolization.
Resumo:
PURPOSE:
To investigate endothelin 1 (Et1)-dependent Ca(2+)-signaling at the cellular and subcellular levels in retinal arteriolar myocytes.
METHODS:
Et1 responses were imaged from Fluo-4-loaded smooth muscle in isolated segments of rat retinal arteriole using confocal laser microscopy.
RESULTS:
Basal [Ca(2+)](i), subcellular Ca(2+)-sparks, and cellular Ca(2+)-oscillations were all increased during exposure to Et1 (10 nM). Ca(2+)-spark frequency was also increased by 90% by 10 nM Et1. The increase in oscillation frequency was concentration dependent and was inhibited by the EtA receptor (Et(A)R) blocker BQ123 but not by the EtB receptor antagonist BQ788. Stimulation of Ca(2+)-oscillations by Et1 was inhibited by a phospholipase C blocker (U73122; 10 µM), two inhibitors of inositol 1,4,5-trisphosphate receptors (IP(3)Rs), xestospongin C (10 µM), 2-aminoethoxydiphenyl borate (100 µM), and tetracaine (100 µM), a blocker of ryanodine receptors (RyRs).
CONCLUSIONS:
Et1 stimulates Ca(2+)-sparks and oscillations through Et(A)Rs. The underlying mechanism involves the activation of phospholipase C and both IP(3)Rs and RyRs, suggesting crosstalk between these Ca(2+)-release channels. These findings suggest that phasic Ca(2+)-oscillations play an important role in the smooth muscle response to Et1 within the retinal microvasculature and support an excitatory, proconstrictor role for Ca(2+)-sparks in these vessels.
Resumo:
The authors use a growth accounting framework to examine growth of the rapidly developing Chinese economy. Their findings support the view that, although feasible in the intermediate term, China's recent pattern of extensive growth is not sustainable in the long run. The authors believe that China will be able to sustain a growth rate of 8 to 9 percent for an extended period if it moves from extensive to intensive growth. They next compare potential growth in China with historical developments in the United States and the European Union. They discuss the differences in production structure and level of development across the three economies that may explain the countries' varied intermediate-term growth prospects. Finally, the authors provide an analysis of "green" gross domestic product and the role of natural resources in China's growth. © 2009, The Federal Reserve Bank of St. Louis.
Resumo:
Recent and emerging security policies and practices claim a mutual vulnerability that closely links human insecurity in failed states with the threat to powerful states from illicit flows. This article first examines this ‘emerging orthodoxy’ of transnational security issues that reinforces the securitisation of poverty and the poor. It then subjects this orthodoxy to theoretical and empirical critique. Theoretically it shows that this orthodoxy is formed as a ‘geopolitical imagination’ that associates and stabilises particular views of weak states and illicit flows in a ‘netwar imagination’ by reasserting and reconfiguring traditional assumptions of the spatiality and nature of threats. A final empirical section, focusing on drug production and nuclear smuggling, argues that those assumptions and their assemblage are a partial, incomplete and often self-referential reading of illicit flows.
Resumo:
We examined the relationship between Individualism/Collectivism and generalized social trust across 31 European nations participating in the European Social Survey. Using multi-level regression analyses, the current study provides the first empirical investigation of the effects of cultural norms of Individualism/Collectivism on generalized social trust while accounting for individuals' own cultural orientations within the same analysis. The results provide clear support for Yamagishi and Yamagishi (1994) emancipation theory of trust, showing a significant and positive relationship between Individualism/Collectivism and generalized social trust, over and above the effect of a country political history of communism and ethnic heterogeneity. Having controlled for individual effects of Individualism/Collectivism it is clear that the results of the current analysis cannot be reduced to an individual-level explanation, but must be interpreted within the context Of macrosocial processes. We conclude by discussing potential mechanisms that could explain why national individualism is more likely to foster trust among people than collectivism.