Plant regeneration from pulse-treated longitudinally sliced half cotyledon node explants of Turkish ochrus chickling [Lathyrus ochrus (L.) D.C.]

The forage legume ochrus chickling [Lathyrus ochrus (L.) D.C.] which is distributed in the Mediterranean region, is gaining importance in terms of economy and agriculture in Turkey. However, the full potential of the legume has yet to be realized due to the presence of neurotoxin, β-N-oxalyl-L-a, β-diaminopropionic acid (ODAP) causing lathyrism. This study aimed to develop an efficient micropropagation system using longitudinally sliced cotyledon node explants for use in Agrobacterium-mediated genetic transformation in the future. The results show that the maximum number of shoots per explant was achieved on MS medium solidified with 8 g/l isubgol gelled medium containing 0.30 mg/l BA-0.2 mg/l NAA. Well-developed shoots were rooted by pulse treatment with 50 mg/l IBA and culturing on an 8 g/l isubgol gel solidified MS medium. The results showed 60% rooting in the treated shoots. The rooted plantlets were transferred to pots containing sand and organic matter and acclimatized

Mitigating Off-Policy Bias in Actor-Critic Methods with One-Step Q-learning: A Novel Correction Approach

Compared to on-policy counterparts, off-policy model-free deep reinforcement learning can improve data efficiency by repeatedly using the previously gathered data. However, off-policy learning becomes challenging when the discrepancy between the underlying distributions of the agent's policy and collected data increases. Although the well-studied importance sampling and off-policy policy gradient techniques were proposed to compensate for this discrepancy, they usually require a collection of long trajectories and induce additional problems such as vanishing/exploding gradients or discarding many useful experiences, which eventually increases the computational complexity. Moreover, their generalization to either continuous action domains or policies approximated by deterministic deep neural networks is strictly limited. To overcome these limitations, we introduce a novel policy similarity measure to mitigate the effects of such discrepancy in continuous control. Our method offers an adequate single-step off-policy correction that is applicable to deterministic policy networks. Theoretical and empirical studies demonstrate that it can achieve a "safe" off-policy learning and substantially improve the state-of-the-art by attaining higher returns in fewer steps than the competing methods through an effective schedule of the learning rate in Q-learning and policy optimization

Learning in Bayesian regulation: Desirable or undesirable?

We examine the social desirability of learning about the regulated agent in a generalized principal-agent model with incomplete information. An interesting result we obtain is that there are situations in which the agent prefers a Bayesian regulator to have more, yet incomplete, information about his private type

Anthrax in Eastern Turkey, 1992–2004

We investigated animal and human anthrax cases during a 13-year period in eastern Turkey. From 1992 to 2004, a total of 464 animal and 503 human anthrax cases were detected. Most cases occurred in summer. Anthrax remains a health problem in eastern Turkey, and preventive measures should be taken

A critical look at quantum diffusion and some of its interesting aspects

A fresh and critical look has been given to the long-time behaviour of the quantum diffusion problem and a marginally more accurate solution has been obtained as compared to the one reported in the recent literature. Attempt has also been made to bring out a few interesting generic features of this problem which may have important bearing on real systems in the quantum domain. © 2007 EDP Sciences/Società Italiana di Fisica/Springer-Verlag

Molecular structure, vibrational spectral investigation and the confirmation analysis of 4-Methylesculetin molecule

WOS: 000333614200003In this work, FT-IR, FT-Raman, and FT-NMR spectra of 4-Methylesculetin molecule are presented for the first time. FT-IR, FT-Raman, and FT-NMR spectra of 4MEC have been recorded and analyzed. The FT-IR and FT-Raman spectra of this molecule are recorded at 4000-400 cm(-1) and 50-3500 cm(-1), respectively. The infrared vibrational frequencies, absolute intensities, potential energy profile, HOMO-LUMO plot and NBO analysis of the molecule have been also predicted using Becke's three-parameter hybrid B3LYP method in the density functional theory DFT method. Calculated and experimental data are in good agreement.Ahi Evran University Research FundAhi Evran University [FEN.4003.12.013]Y. Erdogdu would like to thank Ahi Evran University Research Fund for its financial support. Project Numbers: FEN.4003.12.013. Computing resources used in this work were provided by the National Center for High Performance Computing of Turkey (UYBHM)

Quantum size effect on the phonon-induced Zeeman splitting in a GaAs quantum dot with Gaussian and parabolic confining potentials

The Zeeman splitting of the ground and the first excited level of a Gaussian GaAs quantum dot is studied in the presence of electron-longitudinal-optical (LO)-phonon interaction incorporating the spin of the electron and is compared with the case of a parabolic dot. It is shown that the Zeeman splitting is suppressed because of the polaronic interaction and becomes strongly size dependent, but the parabolic confinement overestimates this Zeeman suppression. It is also shown that although the energy levels are split because of the spin-field interaction, the cyclotron frequencies and the Zeeman lines are independent of the electron spin in the dipole transition. © 2008 Elsevier B.V. All rights reserved

Polaronic effects in a Gaussian quantum dot

The problem of an electron interacting with longitudinal-optical (LO) phonons is investigated in an N-dimensional quantum dot with symmetric Gaussian confinement in all directions using the Rayleigh-Schrödinger perturbation theory, a variant of the canonical transformation method of Lee-Low-Pines, and the sophisticated apparatus of the Feynman-Haken path-integral technique for the entire range of the coupling parameters and the results for N = 2 and N = 3 are obtained as special cases. It is shown that the polaronic effects are quite significant for small dots with deep confining potential well and the parabolic potential is only a poor approximation of the Gaussian confinement. The Feynman-Haken path-integral technique in general gives a good upper bound to the ground state energy for all values of the system parameters and therefore is used as a benchmark for comparison between different methods. It is shown that the perturbation theory yields for the ground state polaron self-energy a simple closed-form analytic expression containing only Gamma functions and in the weak-coupling regime it provides the lowest energy because of an efficient partitioning of the Gaussian potential and the subsequent use of a mean-field kind of treatment. The polarization potential, the polaron radius and the number of virtual phonons in the polaron cloud are obtained using the Lee-Low-Pines-Huybrechts method and their variations with respect to different parameters of the system are discussed. © 2007 Elsevier Ltd. All rights reserved