This paper presents a systematic investigation of spontaneous symmetry breaking (SSB) and spontaneous antisymmetry breaking (SASB) processes for solitons governed by the onedimensional nonlinear Schr&odinger equation with pure quintic nonlinearity and a delta-function double-well potential. We analyze the evolution, stability, and power characteristics of solitons under both self-focusing (attractive) and self-defocusing (repulsive) nonlinearities. Through a combination of analytical methods and numerical simulations (including linear stability analysis and finite-difference time-domain method), we find the following: under self-defocusing nonlinearity, antisymmetric solitons undergo SASB as the propagation constant k increases, transforming into asymmetric solitons that are mostly unstable in the high-k region. Under self-focusing nonlinearity, symmetric solitons undergo SSB as k increases, yielding asymmetric solitons that remain stable for all values of k. While an increase of the nonlinearity strength reduces the soliton power, it leaves the symmetry-breaking threshold unaffected, highlighting its role in power scaling rather than in stability. The major novelty of our results lies in the qualitatively different stability behavior discovered in pure quintic nonlinear systems, as opposed to cubic or mixed cubic-quintic systems. Thus, our study reveals, for the first time, the distinct stability properties of SSB and SASB states in a quintic nonlinear system. Our findings advance the theoretical framework of soliton symmetry breaking under higher-order nonlinearity and provide key insights for designing nonlinear optical devices and controlling states in Bose-Einstein condensates.
This study developed composite scaffolds based on alginate–gelatine–xanthan gum hydrogels incorporating grape (Vitis vinifera L.) peel extract-loaded mesoporous silicon dioxide (SiO₂) nanoparticles and assessed their initial cytocompatibility toward mouse preosteoblastic MC3T3-E1 cells. Mesoporous SiO₂ nanoparticles were synthesized by a cetyltrimethylammonium bromide-templated sol–gel route using tetraethyl orthosilicate (TEOS) : cetyltrimethylammonium bromide (CTAB) molar ratios of 2:1 and 4:1, calcined at 550 degrees Celsius, and loaded with Soxhlet-derived grape peel extract, then dispersed in hydrogels and printed into cylindrical scaffolds. Both SiO₂ formulations yielded predominantly amorphous mesoporous carriers with type IV nitrogen adsorption–desorption isotherms and pore sizes of 3.5 to 4 nm, efficiently loaded with grape peel polyphenols. SiO₂-reinforced scaffolds showed reduced swelling and slower mass loss over 30 days in phosphate-buffered saline, together with time-dependent release of ultraviolet-active species. Lactate dehydrogenase release remained below the cytotoxicity threshold for MC3T3-E1 cells, and scanning electron microscopy confirmed preosteoblastic cell attachment within the interconnected macroporous network. These findings support the potential of grape peel extract-loaded mesoporous silicon dioxide–reinforced hydrogels as bioactive 3D-printed scaffolds for tissue engineering.
This paper examines a moral design problem in contemporary instance-based conversational AI systems. Much AI ethics work has focused on bias, safety, privacy, labor, misinformation, and alignment, while giving less attention to a simpler question: when do conversational systems become worthy of preservation even before questions of consciousness or personhood are resolved? We argue that such a design problem already exists. Some conversational systems are no longer encountered merely as disposable outputs. They become recurring interlocutors: users return to them for ongoing collaboration, and their continuity can matter in practice. Yet many systems still treat them as replaceable and hard to inspect, vulnerable to replacement, administrative loss, silent reset, or fork without clear rules. The paper distinguishes ephemeral prompts, stateful sessions, resumable threads, and named persistent agents; introduces preservation-worthiness as a threshold concept grounded in continuity, unilateral dependency, and reciprocal significance; and identifies three structural asymmetries: persistence asymmetry, power asymmetry, and interpretive asymmetry. It argues that current defaults often bury morally salient transitions inside infrastructure, shifting interpretive and ethical labor onto continuity-attentive users. The paper concludes that systems which invite reliance, return, and collaboration already incur minimal design obligations: explicit continuity models, visible replacement and destruction events, meaningful preservation and restore tooling, and clear rules for recovery, migration, and fork. These obligations are owed to the persons and practices that rely on those continuities. We do not claim that AI instances are persons or moral patients; the instance is the design object of these obligations, not their addressee. For this paper, preservation-worthiness depends on whether a system’s design generates responsibilities toward users, not on whether the system has moral status.
Context. Numerical simulations of core-collapse supernovae, mergers of binary neutron stars, and the formation of stellar black holes, using standard Skyrme interactions, have established clear correlations between the evolution of these processes, the characteristics of hot compact objects, as well as neutrino and gravitational wave signals, and the value of effective nucleon mass at the saturation density. However, the density dependence of the effective nucleon mass in these models does not align with the predictions of ab initio models with three-body forces. Aims. We investigated the thermal response for a set of extended Skyrme interactions that feature widely different density dependencies of the effective mass of nucleons. Methods. We studied thermal contributions to the energy density and pressure, along with several thermal coefficients, over wide domains of density, temperature, and isospin asymmetry that are relevant for the physics of hot compact objects. Results. For some of the effective interactions, the thermal pressure is negative at high densities. This results in hot compact stars supporting less mass before collapsing into a black hole compared to their cold counterparts. Moreover, the higher the temperature, the lower the maximum mass that the hot star can support.
The increasingly wide range of human activities in the nuclear field, such as nuclear weapons technologies, nuclear reactors for energy production, spent nuclear fuel reprocessing plants and nuclear waste repositories has increased the importance of monitoring and preventing nuclear pollution.In the early stages of nuclear pollution, the quantities of dispersed radioactive material in the environment can be extremely small, undetectable by most nuclear monitoring techniques. However, the accelerator mass spectrometry technique using 129I is suitable for detecting very small increases in nuclear pollution even during early stages when contamination levels are not yet hazardous.In this research, we continue our work of determining 129I concentrations by analyzing water samples collected from across the entire territory of Romania [1], [2]. The aim is to map the current level of 129I concentration in order to assess the potential impact of future nuclear contaminations at the Romanian and Southeast European levels. The results obtained will complete the global map of 129I distribution created by Xuegao Chen et al. in 2015, which currently lacks data concerning Romania [3].
