3,902 research outputs found
Holographic Bjorken Flow at Large-D
We use gauge/gravity duality to study the dynamics of strongly coupled gauge
theories undergoing boost invariant expansion in an arbitrary number of
space-time dimensions (D). By keeping the scale of the late-time energy density
fixed, we explore the infinite-D limit and study the first few corrections to
this expansion. In agreement with other studies, we find that the large-D
dynamics are controlled by hydrodynamics and we use our computation to
constrain the leading large-D dependence of a certain combination of transport
coefficients up to 6-th order in gradients. Going beyond late time physics, we
discuss how non-hydrodynamic modes appear in the large-D expansion in the form
of a trans-series in D, identical to the non-perturbative contributions to the
gradient expansion. We discuss the consequence of this trans-series in the
non-convergence of the large-D expansion.Comment: 38 pages, 3 figures. v2: Typos corrected, references adde
Theoretical and experimental study of a new thiosulfonate derivative: Methyl trifluoromethanethiosulfonate, CF3SO2SCH3. Conformational transferability in CX3SO2S-R compounds
Methyl trifluoromethanethiosulfonate, CF3SO2SCH3, was synthesized and characterized by 13C NMR, 19F NMR, and vibrational spectroscopy. This structural study was supported by MP2 and DFT (B3LYP and MPW1PW91) calculations, which revealed a strong dependence of the theoretical structure on the polarization of the basis set. Theoretical data indicate that only one conformer, gauche, is predicted by rotating around the SâS bond. This conformational preference was studied using the total energy scheme and natural bond orbital partition scheme. These results evidence that electron delocalization and especially LP S â Ïâ C(1)-S interactions play an interesting role in the reactivity-structure connection of oxoesters and thioesters. Gas and liquid infrared and liquid Raman spectra were recorded and assigned. The experimental vibrational data along with theoretical force constants (B3LYP) were used to define a scaled quantum mechanical force field, which enabled the reproduction of the measured frequencies with a final root-mean-square deviation of 8.06 cmâ1.Fil: GalvĂĄn, Jorge Edgardo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - TucumĂĄn. Instituto de QuĂmica del Noroeste. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia. Instituto de QuĂmica del Noroeste; ArgentinaFil: Contreras Aguilar, Elizabeth. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Centro de QuĂmica InorgĂĄnica ; ArgentinaFil: Defonsi Lestard, Maria Eliana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - TucumĂĄn. Instituto de QuĂmica del Noroeste. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia. Instituto de QuĂmica del Noroeste; ArgentinaFil: Tuttolomondo, MarĂa Eugenia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - TucumĂĄn. Instituto de QuĂmica del Noroeste. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia. Instituto de QuĂmica del Noroeste; ArgentinaFil: Ulic, Sonia Elizabeth. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Centro de QuĂmica InorgĂĄnica ; Argentina. Universidad Nacional de LujĂĄn. Departamento de Ciencias BĂĄsicas; ArgentinaFil: Ben Altabef, AĂda. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - TucumĂĄn. Instituto de QuĂmica del Noroeste. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia. Instituto de QuĂmica del Noroeste; Argentin
Growth, photosynthetic pigments, phenolic content and biological activities of Foeniculum vulgare Mill., Anethum graveolens L. and Pimpinella anisum L. (Apiaceae) in response to zinc
The effect of zinc (Zn) on phenols, antioxidant activities (free radicals' scavenging activities, inhibition of lipid peroxidation, chelating activity and reducing power), and enzyme inhibition activities of acetylcholinesterase, lipoxygenase and tyrosinase of anise, dill and two cultivars of fennel [Latina" (F-L) and "Doux de Florence" (F-DF)] aqueous extracts was evaluated for the first time. At the same time, growth and photosynthetic pigment contents were also estimated. A significant decrease in all growth parameters, such as plant height, fresh and dry weights of aerial parts and roots was statistically proved in the presence of 2 mM Zn. An enhancement of Zn accumulation was observed, particularly in aerial part. Exposure to 2 mM Zn induced quantitative changes in the phenols of all tested extracts. In fennel extracts, a decrease of phenol content was observed when treated with Zn, whereas an increase was found in dill and anise extracts submitted to Zn treatment. All samples, either in the presence or absence of Zn, showed antioxidant activity, independent on the tested assay, with the exception of the cultivar F-DF (treated and non-treated), which was unable to scavenge NO radicals. Zn-treated dill and anise presented usually higher antioxidant activity. Concerning inhibitory activities against acetylcholinesterase, lipoxygenase and tyrosinase enzymes, both treated and non-treated F-DF did not inhibit acetylcholinesterase activity. Zinc-treated F-DF was also unable to inhibit lipoxygenase activity. The remaining species presented capacity for inhibiting those enzymes and tyrosinase as well, but their abilities varied in response to Zn excess.Portuguese National Funding Agency for Science, Research and Technology (Fundacao para a Ciencia e a Tecnologia - FCTPortugal) [UID/BIA/04325/2013-MEDTBIO, UID/Multi/04326/2013]info:eu-repo/semantics/publishedVersio
Phenotypical and functional characteristics of mesenchymal stem cells from bone marrow: comparison of culture using different media supplemented with human platelet lysate or fetal bovine serum
High spectro-temporal purity single-photons from silicon micro-racetrack resonators using a dual-pulse configuration
Single-photons with high spectro-temporal purity are an essential resource
for quantum photonic technologies. The highest reported purity up until now
from a conventional silicon photonic device is 92% without any spectral
filtering. We have experimentally generated and observed single-photons with
98.0+-0.3 % spectro-temporal purity using a conventional micro racetrack
resonator and an engineered dual pump pulse
Integrate and scale:A source of spectrally separable photon pairs
Integrated photonics is a powerful contender in the race for a fault-tolerant quantum computer, claiming to be a platform capable of scaling to the necessary number of qubits. This necessitates the use of high-quality quantum states, which we create here using an all-around high-performing photon source on an integrated photonics platform. We use a photonic molecule architecture and broadband directional couplers to protect against fabrication tolerances and ensure reliable operation. As a result, we simultaneously measure a spectral purity of %, a pair generation rate of MHz mW, and an intrinsic source heralding efficiency of %. We also see a maximum coincidence-to-accidental ratio of . We claim over an order of magnitude improvement in the trivariate trade-off between source heralding efficiency, purity and brightness. Future implementations of the source could achieve in excess of % purity and heralding efficiency using state-of-the-art propagation losses
Quantifying Hidden Nonlinear Noise in Integrated Photonics
We present experimental and simulated results to quantify the impact of nonlinear noise in integrated photonic devices relying on spontaneous four-wave mixing. Our results highlight the need for design rule adaptations to mitigate the otherwise intrinsic reduction in quantum state purity. The best strategy in devices with multiple parallel photon sources is to strictly limit photon generation outside of the sources. Otherwise, our results suggest that purity can decrease below 40%
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