Search results for "Approach"
showing 10 items of 1654 documents
On the measured lifetime of light hypernuclei 3ΛH and 4ΛH
2014
A statistical combination of the experimental lifetime estimations available in the literatures is performed for 3 Λ H and 4 Λ H, including several recent measurements. The combined average values of the lifetime for 3 Λ H and 4 Λ H are respectively 216−16+19 ps and 192−18+20 ps with a reduced χ2 of 0.89 and 0.48. A new insight into the lifetime estimation of the HypHI Phase 0 experiment by a Bayesian approach is also presented. In this approach, several different prior distributions including the combination of previous lifetime data and a Jeffrey prior are used. The principal mode and the smallest credible interval at 68% of the posterior distribution, given by the prior belief of the pre…
In-medium modifications of the pi pi interaction in photon-induced reactions
2002
Differential cross sections of the reactions $(\gamma,\pi^\circ\pi^\circ)$ and $(\gamma,\pi^\circ\pi^++\pi^\circ\pi^-)$ have been measured for several nuclei ($^1$H,$^{12}$C, and $^{\rm nat}$Pb) at an incident-photon energy of $E_{\gamma}$=400-460 MeV at the tagged-photon facility at MAMI-B using the TAPS spectrometer. A significant nuclear-mass dependence of the $\pi\pi$ invariant-mass distribution is found in the $\pi^\circ\pi^\circ$ channel. This dependence is not observed in the $\pi^\circ\pi^{+/-}$ channel and is consistent with an in-medium modification of the $\pi\pi$ interaction in the $I$=$J$=0 channel. The data are compared to $\pi$-induced measurements and to calculations within …
Fast shuttling of a trapped ion in the presence of noise
2014
We theoretically investigate the motional excitation of a single ion caused by spring-constant and position fluctuations of a harmonic trap during trap shuttling processes. A detailed study of the sensitivity on noise for several transport protocols and noise spectra is provided. The effect of slow spring-constant drifts is also analyzed. Trap trajectories that minimize the excitation are designed combining invariant-based inverse engineering, perturbation theory, and optimal control.
A Perturbative Approach to Continuous-Time Quantum Error Correction
2014
We present a novel discussion of the continuous-time quantum error correction introduced by Paz and Zurek in 1998 [Paz and Zurek, Proc. R. Soc. A 454, 355 (1998)]. We study the general Lindbladian which describes the effects of both noise and error correction in the weak-noise (or strong-correction) regime through a perturbative expansion. We use this tool to derive quantitative aspects of the continuous-time dynamics both in general and through two illustrative examples: the 3-qubit and the 5-qubit stabilizer codes, which can be independently solved by analytical and numerical methods and then used as benchmarks for the perturbative approach. The perturbatively accessible time frame featur…
QCD condensates from tau-decay data: A functional approach
2004
We study a functional method to extract the V − A condensate of dimension 6 from a comparison of τ -decay data with the asymptotic space-like QCD prediction. Our result is in agreement within errors with that from conventional analyses based on finite energy sum rules.
A dynamical mean field theory for the study of surface diffusion constants
1997
We present a combined analytical and numerical approach based on the Mori projection operator formalism and Monte Carlo simulations to study surface diffusion within the lattice-gas model. In the present theory, the average jump rate and the susceptibility factor appearing are evaluated through Monte Carlo simulations, while the memory functions are approximated by the known results for a Langmuir gas model. This leads to a dynamical mean field theory (DMF) for collective diffusion, while approximate correlation effects beyond DMF are included for tracer diffusion. We apply our formalism to three very different strongly interacting systems and compare the results of the new approach with th…
Nuclear density functional theory with a semi-contact 3-body interaction
2015
International audience; Theories combining nuclear density functional approach (DFT) and effects beyond the independent particle/quasi-particle limit have attracted much attention recently. In particular, such theories, generically referred as “beyond mean-field” (BMF) seem unavoidable to account for both single-particle effects and complex quantum internal phenomena in nuclear finite many-body nuclear systems. It has been realized recently that BMF theories might lead to specific difficulties when applied within the nuclear DFT context. An example is the appearance of divergences in configuration mixing approaches. A short summary of the difficulties is given here. One source of problem is…
Quercetin and MicroRNA Interplay in Apoptosis Regulation in Ovarian Cancer
2020
The multifaceted nature of ovarian cancer has severely hampered the development of effective therapeutics over the years. The complicate nature of ovarian cancer makes it therapeutically challenging, therefore, there has been a renewed interest in phytochemistry. Phytochemicals have emerged as a potential therapeutic option due to less side effects. Moreover, the signaling inhibition properties have also been studied extensively in recent times. A growing number of data obtained via high-throughput technologies has started to delineate the complex oncogenic signaling networks, thus broadening the therapeutic opportunities. Within the network, microRNAs (miRNAs) have been shown to play a ve…
Shear strength degradation due to flexural ductility demand in circular RC columns
2014
An analytical model was developed to estimate the shear-strength degradation and the residual capacity of circular reinforced concrete (RC) columns subjected to seismic action. The proposed model is an upgrade of a previously proposed model for axial force $$N$$ , bending moment $$M$$ and shear force $$V$$ ( $$N$$ – $$M$$ – $$V$$ ) interaction domain evaluation for rectangular and circular cross-section RC elements subjected to static loading. The model was extended to the case of circular cross-sections subjected to seismic actions with limitation of the range of variability of the deviation angle between the directions of the stress fields and the crack inclinations, as a function of the …
Dynamics of institutional and family ties of the child placed in foster care : the contribution of attachment theory and the psychodynamic approach
2019
This research studies dynamics of the institutional and family ties of the foster child with a complementary approach that articulates attachment theory and a psychodynamic perspective. METHODOLOGY. Through a mixed (quantitative and qualitative) and longitudinal (one year) methodology, the research was conducted with ten children (N=10) who have just arrived for the first time in foster care and professionals (N=17) who surround them. Tools used were the CCH, RQ, Ca-mir, Edicode (for attachment) and projective proofs of drawings with semi-structured clinical research interviews (for transfer and counter-transfer investments). RESULTS. Results show that children who have just arrived in fost…