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A cold neutron induced fission experiment recently took place at the Institute Laue-Langevin (ILL) in Grenoble. The neutron beam was provided by the nuclear reactor facility at ILL and the detector setup that was used for the γ-spectroscopy of the fission products consisted mainly of the detectors of the EXOGAM array [1], thereby the name of the campaign is EXILL. The main purpose of our measurement was to investigate the nuclei in the region with N = 50 close to 78Ni as well as the nuclei close to the N = 82 shell closure. In this paper, the motivation of the experiment is described as well as the experimental setup and the status of the ongoing data analysis.

The present paper concerns the study of the even–even 122–138Ce isotopes, based on the cranked Nilsson–Strutinsky model. The energy levels are calculated for these nuclei and the potential energy surfaces are represented in deformation parameters plane (ɛ2, γ). The configurations are assigned to different bands using the best difference between calculated and observed energies. The nuclear shape evolution as function of the spin is examined and explored by two separate studies, using, respectively, the values of deformation parameters in the first study and the analysis of kinetic and dynamic moments of inertia ((1) and (2)) in the second one. The results of both studies are consistent. [ABSTRACT FROM AUTHOR]

High-spin states in 139Ce have been populated using the 130Te(14C,5n) reaction. The level scheme has been extended to higher spins, including a new band of dipole transitions. The parity of several states has been changed from negative to positive, mainly based on the comparison with the level structure of the core nucleus 140Ce and the results of a realistic shell-model calculation. The dipole band is interpreted as a magnetic rotation band with πh11/2² ⊗ νh-111/2 configuration built on small deformation axial shape with (ɛ2 = 0.12,γ = 0°). [ABSTRACT FROM AUTHOR]

The Drd2 gene, encoding the dopamine D2 receptor (D2R), was recently indicated as a potential target in the etiology of lowered sociability (i.e., social withdrawal), a symptom of several neuropsychiatric disorders such as Schizophrenia and Major Depression. Many animal species show social withdrawal in response to stimuli, including the vinegar fly Drosophila melanogaster and mice, which also share most human disease-related genes. Here we will test for causality between Drd2 and sociability and for its evolutionary conserved function in these two distant species, as well as assess its mechanism as a potential therapeutic target. During behavioral observations in groups of freely interacting D. melanogaster, Drd2 homologue mutant showed decreased social interactions and locomotor activity. After confirming Drd2's social effects in flies, conditional transgenic mice lacking Drd2 in dopaminergic cells (autoreceptor KO) or in serotonergic cells (heteroreceptor KO) were studied in semi-natural environments, where they could freely interact. Autoreceptor KOs showed increased sociability, but reduced activity, while no overall effect of Drd2 deletion was observed in heteroreceptor KOs. To determine acute effects of D2R signaling on sociability, we also showed that a direct intervention with the D2R agonist Sumanirole decreased sociability in wild type mice, while the antagonist showed no effects. Using a computational ethological approach, this study demonstrates that Drd2 regulates sociability across evolutionary distant species, and that activation of the mammalian D2R autoreceptor, in particular, is necessary for social functioning., (© 2023. The Author(s).)

We present a theoretical study of various definitions of laser beam width in a given cross section. Quality of the beam is characterized by dimensionless beam propagation products (BPPs) Δx·Δθ(x)/λ, which are different for the 21 definitions presented, but are close to 1. Six particular beams are studied in detail. In the process, we had to review the properties for the Fourier transform of various modifications and the relationships between them: physical Fourier transform (PFT), mathematical Fourier transform (MFT), and discrete Fourier transform (DFT). We found an axially symmetric self-MFT function, which may be useful for descriptions of diffraction-quality beams. In the appendices, we illustrate the thesis "the Fourier transform lives on the singularities of the original."

Recording of volume Bragg gratings (VBGs) in photo-thermo-refractive glass is limited to a maximum refractive index change about 0.002. We discuss various saturation curves and their influence on the amplitudes of recorded gratings. Special attention is given to multiplexed VBGs aimed at recording several gratings in the same volume. The best shape of the saturation curve for production of the strongest gratings is the threshold-type curve. Two-photon absorption as a mechanism of recording also allows increasing the strength of multiplexed VBGs.

Analyzing the first equation in the BBGKY chain of equations for an equilibrium liquid-gas system, we derived the analytical expression for the atom work function from liquid into gas. The coupling between the atom work function from liquid into vacuum and the stability criterion of liquid in limiting points of the first type was shown (using I.Z. Fisher classification). As it turned out, Fisher's criterion corresponds to the condition of atomization. We have expressed the state equation in terms of the atom work function from liquid into vacuum and performed calculations of the limiting line of stability composed of limiting points of the first type for argon. Our model discovers an interesting effect of the negative atom work function: at a constant volume of liquid, on a temperature rise (also at a fixed temperature and decreasing specific volume of liquid) the atom work function drops and takes a negative value with a modulus that is significantly larger than the atomic thermal energy. We propose a new two-stage mechanism of sonoluminescence based on non-thermal processes in liquid in a state with a negative atom work function. The first stage includes the emission of atoms from the interior of the bubble into gas at hyper-thermal velocities. At the second stage, a collision of emitted flow takes place between the gas atoms along with the implosion of the central part of the bubble. As a result of the impact excitation, ionization and the subsequent recombination, a flash of electromagnetic radiation develops that can be seen in sonoluminescence experiments.

This was a double-blind comparison of methadyl acetate and two dose levels of methadone hydrochloride in the maintenance of 430 street heroin addicts from 12 Veterans Administration hospitals. The starting sample consisted of 146 patients receiving low-dose methadone, 142 patients receiving methadyl acetate. Patients were first given 30 mg of both drugs, and doses were incremented by 10 mg/week until they stabilized at methadyl acetate, 80 mg three times a week, and methadone hydrochloride, 50 mg daily or 100 mg daily. Dosage was fixed for the balance of the 40-week treatment period. Safety was evaluated by clinical and laboratory observations conducted at frequent intervals throughout the study. Relative efficacy was evaluated by illicit drug use, program retention and attendance, and global staff judgments. It is concluded that methadyl acetate is as safe a drug as methadone and that it compares favorably with highdose methoadone in terms of efficacy. Both methyadyl acetate and high-dose methadone appear to be better maintenance regimens than low-dose methadone under the conditions of this study.