1,271 research outputs found
Schemes for Parallel Quantum Computation Without Local Control of Qubits
Typical quantum computing schemes require transformations (gates) to be
targeted at specific elements (qubits). In many physical systems, direct
targeting is difficult to achieve; an alternative is to encode local gates into
globally applied transformations. Here we demonstrate the minimum physical
requirements for such an approach: a one-dimensional array composed of two
alternating 'types' of two-state system. Each system need be sensitive only to
the net state of its nearest neighbors, i.e. the number in state 1 minus the
number in state 2. Additionally, we show that all such arrays can perform quite
general parallel operations. A broad range of physical systems and interactions
are suitable: we highlight two potential implementations.Comment: 12 pages + 3 figures. Several small corrections mad
The conformation of apamin
AbstractEnergy minimisation techniques are used as a tool to distinguish between different proposed models for the structure of the bee venom polypeptide apamin. The influence of electrostatic interactions on the resultant energies is noted. The model of Hider and Ragnarsson [(1980) FEBS Lett. 111, 189-193] is found to be of consistently low energy
Valuation of environmental health damages in developing countries : some observations
Meeting: EEPSEA Biannual Workshop, 15th, Nov. 2000, Chiang Mai, THPrepared for the Worksho
Acute synovitis and intra-articular methylprednisolone acetate in ponies
AbstractObjective: To determine how acute synovitis, with and without intra-articular methylprednisolone acetate (MPA), affect synthesis of proteoglycan, total protein, and collagen in articular cartilage and total protein synthesis in synovial membrane.Design: Synovitis was induced in 10 ponies by the injection of 0.5 ng lipopolysaccharide (LPS) into the left radiocarpal and midcarpal joints every 2 days for a total of four treatments. Synovitis was documented by clinical examination and synovial fluid analyses. Two days before euthanasia, MPA (0.1 mg/kg) was injected with the last dose of LPS into both the left and right radiocarpal and midcarpal joints of five of these ponies. Proteoglycan synthesis in articular cartilage explants from these joints was measured by incorporation of sodium [35S]sulfate. The size of the proteoglycan monomers and their aggregation with hyaluronan was assessed by size-exclusion chromatography. Protein synthesis in articular cartilage was measured by incorporation of [3H]proline and collagen synthesis by conversion of [3H]proline into [3H]hydroxyproline. Protein synthesis was measured in synovial membrane explants by incorporation of [35S]methionine.Results: Ponies developed carpal effusion and mild lameness accompanied by increased total nucleated cell count and total solids in synovial fluid in response to the LPS injections. Moderate to severe synovial membrane proliferation and inflammation were observed histopathologically in joints injected with LPS but no consistent light-microscopical changes were observed in the articular cartilage from these joints. Intra-articular MPA alone was associated with decreased proteoglycan synthesis and increased protein and collagen synthesis in the cartilage explants. Total protein synthesis by synovial membrane was also increased by MPA alone. In contrast, no differences in protein or proteoglycan synthesis were observed in explants from the joints with synovitis, with or without intra-articular MPA. Treatment with MPA, LPS, and LPS/MPA did not alter proteoglycan aggregate size, but LPS-induced synovitis resulted in an increase in the second largest population of monomers. MPA increased the synthesis of small proteoglycan monomers.Conclusion: Based on the methods used, acute synovitis prevented changes induced by intra-articular MPA alone. Results suggested that the effect of intra-articular MPA on joint metabolism was different between inflamed and normal joints. Experimental studies must consider the effect of inflammation, as well as the potential to introducein vitroculture artifacts when investigating the effect of intra-articular corticosteroids on chondrocyte function
BRST Analysis of Physical States for 2D (Super) Gravity Coupled to (Super) Conformal Matter
We summarize some recent results on the BRST analysis of physical states of
2D gravity coupled to c<=1 conformal matter and the supersymmetric
generalization.Comment: 11 page
Orbital Ordering in Paramagnetic LaMnO3 and KCuF3
{\it Ab-initio} studies of the stability of orbital ordering, its coupling to
magnetic structure and its possible origins (electron-phonon and/or
electron-electron interactions) are reported for two perovskite systems,
LaMnO and KCuF. We present a new Average Spin State (ASS) calculational
scheme that allowed us to treat a paramagnetic state. Using this scheme, we
succesfully described the experimental magnetic/orbital phase diagram of both
LaMnO and KCuF in crystal structures when the Jahn-Teller distortions
are neglected. Hence, we conclude that the orbital ordering in both compounds
is purely electronic in origin.Comment: 10 pages, 5 figure
Test of Sum Rules in Nucleon Transfer Reactions
The quantitative consistency of nucleon transfer reactions as a probe of the occupancy of valence orbits in nuclei is tested. Neutron-adding, neutron-removal, and proton-adding transfer reactions were measured on the four stable even Ni isotopes, with particular attention to the cross section determinations. The data were analyzed consistently in terms of the distorted wave Born approximation to yield spectroscopic factors. Valence-orbit occupancies were extracted, utilizing the Macfarlane-French sum rules. The deduced occupancies are consistent with the changing number of valence neutrons, as are the vacancies for protons, both at the level of <5%. While there has been some debate regarding the true “observability” of spectroscopic factors, the present results indicate that empirically they yield self-consistent results
A FABP4-PPARγ signaling axis regulates human monocyte responses to electrophilic fatty acid nitroalkenes
Nitro-fatty acids (NO2-FA) are electrophilic lipid mediators derived from unsaturated fatty acid nitration. These species are produced endogenously by metabolic and inflammatory reactions and mediate anti-oxidative and anti-inflammatory responses. NO2-FA have been postulated as partial agonists of the Peroxisome Proliferator-Activated Receptor gamma (PPARγ), which is predominantly expressed in adipocytes and myeloid cells. Herein, we explored molecular and cellular events associated with PPARγ activation by NO2-FA in monocytes and macrophages. NO2-FA induced the expression of two PPARγ reporter genes, Fatty Acid Binding Protein 4 (FABP4) and the scavenger receptor CD36, at early stages of monocyte differentiation into macrophages. These responses were inhibited by the specific PPARγ inhibitor GW9662. Attenuated NO2-FA effects on PPARγ signaling were observed once cells were differentiated into macrophages, with a significant but lower FABP4 upregulation, and no induction of CD36. Using in vitro and in silico approaches, we demonstrated that NO2-FA bind to FABP4. Furthermore, the inhibition of monocyte FA binding by FABP4 diminished NO2-FA-induced upregulation of reporter genes that are transcriptionally regulated by PPARγ, Keap1/Nrf2 and HSF1, indicating that FABP4 inhibition mitigates NO2-FA signaling actions. Overall, our results affirm that NO2-FA activate PPARγ in monocytes and upregulate FABP4 expression, thus promoting a positive amplification loop for the downstream signaling actions of this mediator.Fil: Lamas Bervejillo, M.. Universidad de la República; UruguayFil: Bonanata, Julieta. Universidad de la República; UruguayFil: Franchini, Gisela Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Richeri, A.. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Marqués, J.M.. Universidad de la República; UruguayFil: Freeman, B.A.. University of Pittsburgh; Estados UnidosFil: Schopfer, Francisco Jose. University of Pittsburgh; Estados UnidosFil: Coitiño, E.L.. Universidad de la República; UruguayFil: Córsico, Betina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Rubbo, H.. Universidad de la República; UruguayFil: Ferreira, A.M.. Universidad de la República; Urugua
Exploring the performance of the spectrometer prisma in heavy zirconium and xenon mass regions
We present results from two recent runs which illustrate the performance of the PRISMA spectrometer in the proximity of the upper limit of its operational interval, namely 96Zr + 124Sn at Elab = 500 MeV and 136Xe + 208Pb at Elab = 930 MeV. In the latter run, the γ array CLARA also allowed us to identify previously unknown γ transitions in the nuclides 136Cs and 134I
Valence nucleon populations in the Ni isotopes
Measurements of neutron-adding, neutron-removing, and proton-adding reactions were carried out for the four stable even Ni isotopes. Particular attention was paid to obtaining precise values of the cross sections at the peaks of the angular distributions. Tests with sum rules for the neutron data indicate that the results are self-consistent at the level of a few tenths of a nucleon. Data on proton-adding reactions were also obtained and analyzed with a slightly different method—while these data are also consistent, the ambiguities are larger. The occupancies of the neutron orbits derived from the data, the proton vacancies, and the energy centroids of the neutron, neutron-hole, and proton single-particle excitations are obtained. The data also provide some estimate about the closure of the 0f7/2 shell. The results are compared to shell-model calculations and may serve as a reference point for future exploration
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