13,943 research outputs found
China’s Energy Situation and Its Implications in the New Millennium
Many are interested in China’s energy situation, however, numerous energy related issues in China still remain unanswered. For example, what are the potential forces driving energy demand and supply? Previous reviews focused only on fossil fuel based energy and ignored other important elements including renewable and ‘clean’ energy sources. The work presented here is intended to fill this gap by bringing the research on fossil-based and renewable energy economic studies together and identifying the potential drivers behind both energy demand and supply to provide a complete picture of China’s energy situation in the new millennium. This will be of interest to anyone concerned with the development of China’s economy in general, and in particular with its energy economy.China China; Energy; Fossil fuels; Renewable Energy
Testing for Energy Market Integration in China
This paper investigates energy market integration in China by employing univariate, and panel-based unit root tests and Granger causality tests applied to a new energy price data set. We identify price series that converge either to absolute or relative price parity. In addition we estimate the rates (speed) at which relative prices converge to their long-run values, and the direction of causality. The results show that gasoline and diesel markets are very well integrated as a whole; and that once some geographically isolated regions are excluded, we can regard the coal market as integrated; however, the electricity market is not well integrated. The estimated intercept terms are all very small and close to zero, such that most of the relative price series can be regarded as convergent to absolute price parity. The convergence rates vary little and are relatively short when compared internationally. A rich set of causal relationships are established many showing bi-directional causality between regional centres.China; Energy; Market integration; Price convergence; Time series tests
China’s Energy Economy: Technical Change, Factor Demand and Interfactor/Interfuel Substitution
With its rapid economic growth, China’s primary energy consumption has exceeded domestic energy production since 1994, leading to a substantial expansion in energy imports, particularly of oil. China’s energy demand has an increasingly significant impact on global energy markets. In this paper Allen partial elasticities of factor and energy substitution, and price elasticities of energy demand, are calculated for China using a two-stage translog cost function approach. The results suggest that energy is substitutable with both capital and labour. Coal is significantly substitutable with electricity and complementary with diesel while gasoline and electricity are substitutable with diesel. China’s energy intensity is increasing during the study period (1995-2004) and the major driver appears to be due to the increased use of energy intensive technology.China; Interfactor/interfuel substitution; Technology; Energy intensity decomposition
China's Energy Economy: Technical Change, Factor Demand and Interfactor/Interfuel Substitution
With its rapid economic growth, China's primary energy consumption has exceeded domestic energy production since 1994, leading to a substantial expansion in energy imports, particularly of oil. China's energy demand has an increasingly significant impact on global energy markets. In this paper Allen partial elasticities of factor and energy substitution, and price elasticities of energy demand, are calculated for China using a two-stage translog cost function approach. The results suggest that energy is substitutable with both capital and labour. Coal is significantly substitutable with electricity and complementary with diesel while gasoline and electricity are substitutable with diesel. China's energy intensity is increasing during the study period (1995-2004) and the major driver appears to be due to the increased use of energy intensive technology.China, Interfactor/interfuel substitution, Technology, Energy intensity decomposition
Chemoenzymatic Synthesis of Triazololactams Structurally Related to Pancratistatin
Four tricyclic lactams that structurally resemble alkaloids with the pancratistatin skeleton were synthetized from bromobenzene by a chemoenzymatic strategy. The sequence involved enzymatic dihydroxylation, efficient stereodirected oxidation of double bonds, inter- or intramolecular Huisgen cycloaddition, and a solvent-free cyclization. The complex structures were obtained in high chemical and optical purity and may be good candidates for biological testing.Fil: de la Sovera, Victoria. Universidad de la República. Facultad de Química. Departamento de Química Orgánica; UruguayFil: Suescun, Leopoldo. Universidad de la República. Laboratorio de Cristalografía, Estado Sólido y Materiales; UruguayFil: Bellomo Peraza, Ana Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias ; ArgentinaFil: González, David. Universidad de la República. Facultad de Química. Departamento de Química Orgánica; Urugua
Assembly and force measurement with SPM-like probes in holographic optical tweezers
We report a high fidelity tomographic reconstruction of the quantum state of photon pairs generated by parametric down-conversion with orbital angular momentum (OAM) entanglement. Our tomography method allows us to estimate an upper and lower bound for the entanglement between the down-converted photons. We investigate the two-dimensional state subspace defined by the OAM states ±ℓ and superpositions thereof, with ℓ=1, 2, ..., 30. We find that the reconstructed density matrix, even for OAMs up to around ℓ=20, is close to that of a maximally entangled Bell state with a fidelity in the range between F=0.979 and F=0.814. This demonstrates that, although the single count-rate diminishes with increasing ℓ, entanglement persists in a large dimensional state space
Sampling of explosive residues: the use of a gelatine-based medium for the recovery of ammonium nitrate
Forensic scientists must be able to recover traces of any original explosive materials not consumed in the detonation, in a careful controlled manner to aid a crime reconstruction. In current sampling techniques, the collection efficiency of post-blast residue is highly variable and often dependent on the swabbing materials and solvent systems used. To address these method limitations, this study presents a gelatine-based sampling medium and assesses its capabilities for the collection of ammonium nitrate. Common surfaces were spotted with a known concentration of ammonium nitrate, the unset gel applied, allowed to set, and then peeled from the surface. The gel was dissolved, and solid phase extraction employed to isolate the target explosive compound and remove the constituents of the gel. The eluate was concentrated and subsequently analysed and quantified. Overall, the gel formulation was able to collect ammonium nitrate from all of the test surfaces, with recoveries ranging from 0.1% to 61.7%. This study presents a gelatine-based formulation that has the potential to become a valuable asset in the forensic tool kit for the collection of explosive traces. A key attribute of the gel is that it offers an alternative recovery tool to conventional swabbing and solvent extraction methods
Porphyromonas gingivalis lipopolysaccharide alters atherosclerotic-related gene expression in oxidized low-density-lipoprotein-induced macrophages and foam cells
The molecular mechanism between atherosclerosis formation and periodontal pathogens is not clear although positive correlation between periodontal infections and cardiovascular diseases has been reported. Objective: To determine if atherosclerosis related genes were affected in foam cells during and after its formation by P. gingivalis lipopolysaccharide (LPS) stimulation. Methods: Macrophages from human THP-1 monocytes were treated with oxidized low density lipoprotein (oxLDL) to induce the formation of foam cells. P. gingivalis LPS was added to cultures of either oxLDL-induced macrophages or foam cells. The expression of atherosclerosis related genes was assayed by quantitative real time PCR and the protein production of granulocyte-macrophage colony-stimulating factor(GM-CSF), monocyte chemotactic protein-1 (MCP-1), IL-1β, IL-10 and IL-12 was determined by ELISA. Nuclear translocation of NF-κB P65 was detected by immunocytochemistry and western blot was used to evaluate IKB-α degradation to confirm the NF-κB pathway activation. Results: P. gingivalis LPS stimulated atherosclerosis related gene expression in foam cells and increased oxLDL induced expression of chemokines, adhesion molecules, growth factors, apoptotic genes, and nuclear receptors in macrophages. Transcription of the pro-inflammatory cytokines IL-1β and IL-12 was elevated in response to LPS in both macrophages and foam cells, whereas the anti-inflammatory cytokine IL-10 was not affected. Increased NF-κB pathway activation was also observed in LPS and oxLDL co-stimulated macrophages. Conclusion: P. gingivalis LPS appears to be an important factor in the development of atherosclerosis by stimulation of atherosclerosis related gene expression in both macrophages and foam cells via activation of the NF-κB pathway
Recommended from our members
Human preferences for sexually dimorphic faces may be evolutionarily novel
This article has been made available through the Brunel Open Access Publishing Fund.A large literature proposes that preferences for exaggerated sex typicality in human faces (masculinity/femininity) reflect a long evolutionary history of sexual and social selection. This proposal implies that dimorphism was important to judgments of attractiveness and personality in ancestral environments. It is difficult to evaluate, however, because most available data come from largescale, industrialized, urban populations. Here, we report the results for 12 populations with very diverse levels of economic development. Surprisingly, preferences for exaggerated sex-specific traits are only found in the novel, highly developed environments. Similarly, perceptions that masculine males look aggressive increase strongly with development, specifically, urbanization. These data challenge the hypothesis that facial dimorphism was an important ancestral signal of heritable mate value. One possibility is that highly developed environments provide novel opportunities to discern relationships between facial traits and behavior by exposing individuals to large numbers of unfamiliar faces, revealing patterns too subtle to detect with smaller samples
Levinson's Theorem for the Klein-Gordon Equation in Two Dimensions
The two-dimensional Levinson theorem for the Klein-Gordon equation with a
cylindrically symmetric potential is established. It is shown that
, where denotes
the difference between the number of bound states of the particle
and the ones of antiparticle with a fixed angular momentum , and
the is named phase shifts. The constants and
are introduced to symbol the critical cases where the half bound
states occur at .Comment: Revtex file 14 pages, submitted to Phys. Rev.
- …