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Food quality control is an important task in the agricultural domain at the postharvest stage for avoiding food losses. The latest achievements in image processing with deep learning (DL) and computer vision (CV) approaches provide a number of effective tools based on the image colorization and image-to-image translation for plant quality control at the postharvest stage. In this article, we propose the approach based on Generative Adversarial Network (GAN) and Convolutional Neural Network (CNN) techniques to use synthesized and segmented VNIR imaging data for early postharvest decay and fungal zone predictions as well as the quality assessment of stored apples. The Pix2PixHD model achieved higher results in terms of VNIR images translation from RGB (SSIM = 0.972). Mask R-CNN model was selected as a CNN technique for VNIR images segmentation and achieved 58.861 for postharvest decay zones, 40.968 for fungal zones and 94.800 for both the decayed and fungal zones detection and prediction in stored apples in terms of F1-score metric. In order to verify the effectiveness of this approach, a unique paired dataset containing 1305 RGB and VNIR images of apples of four varieties was obtained. It is further utilized for a GAN model selection. Additionally, we acquired 1029 VNIR images of apples for training and testing a CNN model. We conducted validation on an embedded system equipped with a graphical processing unit. Using Pix2PixHD, 100 VNIR images from RGB images were generated at a rate of 17 frames per second (FPS). Subsequently, these images were segmented using Mask R-CNN at a rate of 0.42 FPS. The achieved results are promising for enhancing the food study and control during the postharvest stage.

Lattice dynamics of a single crystal of lawsonite were studied over a broad range of frequencies (1 Hz to 20 THz) using impedance, THz time-domain and infrared spectroscopies. Based on polarized spectra of complex permittivity ε ^ measured as a function of temperature between 10 K and 500 K, we analyzed the properties of the two known phase transitions—an antiferrodistortive one near T c 1 = 270 K and a ferroelectric one, occurring at T c 2 = 124 K . The former one is accompanied by a flat maximum in the THz-range permittivity ε ^ c near T c 1 , which is due to an overdamped polar excitation in the E ‖ c spectra reflecting the dynamics of water and hydroxyl groups. The strength of this mode decreases on cooling below T c 1 , and the mode vanishes below T c 2 due to hydrogen ordering. At the pseudoproper ferroelectric phase transition, two independent anomalies in permittivity were observed. First, ε ^ a exhibits a peak at T c 2 = 124 K due to critical slowing down of a relaxation in the GHz range. Second, infrared and THz spectra revealed an optical phonon softening towards T c 2 which causes a smaller but pronounced maximum in ε ^ b . Such anomaly, consisting in a soft mode polarized perpendicularly to the ferroelectric axis, is unusual in ferroelectrics.

To obtain materials with desired properties, material compositions are primarily altered, whereas thin films offer additional unique avenues. By combining state‐of‐the‐art first‐principles calculations and experimental investigations of thin films of strontium titanate as an exemplary representative of a broad class of perovskite oxides and the extensive family of ferroelectrics, a novel approach is presented to achieving superior material responses to external stimuli. The findings reveal that substrate‐imposed deformations, or strains, significantly alter the frequencies and magnitudes of atomic vibrations in thin films. Consequently, material‐specific response‐stimulus coefficients can become strain‐dependent. The strain‐dependent Curie constant, which characterizes the dielectric response to thermal stimuli, is theoretically justified and experimentally validated. Given that atomic vibrations fundamentally govern various response coefficients in a wide range of materials, and that thin films are typically deformed by substrates, it is anticipated that unprecedented responses can be generally attained through substrate‐induced control of atomic vibrations in thin films. Many material‐specific coefficients, which relate external stimuli and functional responses, are constants governed by atomic vibrations. This work demonstrates the concept of controlling such response coefficients by deformations, or strain, through strain‐induced changes in atomic vibrations. As a proof of concept, the dependence of the Curie constant on substrate‐imposed strain in SrTiO3 films is theoretically predicted and experimentally validated.

Proton therapy is one of the promising radiotherapy modalities for the treatment of deep-seated and unresectable tumors, and its efficiency can further be enhanced by using boron-containing substances. Here, we explore the use of elemental boron (B) nanoparticles (NPs) as sensitizers for proton therapy enhancement. Prepared by methods of pulsed laser ablation in water, the used B NPs had a mean size of 50 nm, while a subsequent functionalization of the NPs by polyethylene glycol improved their colloidal stability in buffers. Laser-synthesized B NPs were efficiently absorbed by MNNG/Hos human osteosarcoma cells and did not demonstrate any remarkable toxicity effects up to concentrations of 100 ppm, as followed from the results of the MTT and clonogenic assay tests. Then, we assessed the efficiency of B NPs as sensitizers of cancer cell death under irradiation by a 160.5 MeV proton beam. The irradiation of MNNG/Hos cells at a dose of 3 Gy in the presence of 80 and 100 ppm of B NPs led to a 2- and 2.7-fold decrease in the number of formed cell colonies compared to control samples irradiated in the absence of NPs. The obtained data unambiguously evidenced the effect of a strong proton therapy enhancement mediated by B NPs. We also found that the proton beam irradiation of B NPs leads to the generation of reactive oxygen species (ROS), which evidences a possible involvement of the non-nuclear mechanism of cancer cell death related to oxidative stress. Offering a series of advantages, including a passive targeting option and the possibility of additional theranostic functionalities based on the intrinsic properties of B NPs (e.g., photothermal therapy or neutron boron capture therapy), the proposed concept promises a major advancement in proton beam-based cancer treatment.

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Intermolecular hydrogen bonds impede long-range (anti-)ferroelectric order of water. We confine H 2 O molecules in nanosized cages formed by ions of a dielectric crystal. Arranging them in channels at a distance of ~5 Å with an interchannel separation of ~10 Å prevents the formation of hydrogen networks while electric dipole-dipole interactions remain effective. Here, we present measurements of the temperature-dependent dielectric permittivity, pyrocurrent, electric polarization and specific heat that indicate an order-disorder ferroelectric phase transition at T 0  ≈ 3 K in the water dipolar lattice. Ab initio molecular dynamics and classical Monte Carlo simulations reveal that at low temperatures the water molecules form ferroelectric domains in the ab -plane that order antiferroelectrically along the channel direction. This way we achieve the long-standing goal of arranging water molecules in polar order. This is not only of high relevance in various natural systems but might open an avenue towards future applications in biocompatible nanoelectronics. Despite the apparent simplicity of a H2O molecule, the mutual ferroelectric ordering of the molecules is unresolved. Here, the authors realize a macroscopic ferroelectric phase transition in a network of dipole-dipole coupled water molecules located in nanopores of gemstone.

We report broadband dielectric spectra of the non-Kramers hexaaluminate PrMgAl(*{11})O(*{19}), revealing a pronounced interplay between permittivity and magnetization at cryogenic temperatures. The zero-field dielectric response follows a Barrett-type quantum-paraelectric form, while a broad dielectric anomaly near 5 K shifts systematically to higher temperatures under applied magnetic fields, evidencing robust magnetoelectric coupling. The inverse permittivity (\\varepsilon'^{-1}(T,H)) scales linearly with (M^{2}), consistent with a biquadratic (P^{2}M^{2}) term in a Landau framework. Fits yield temperature-dependent coupling constants (\\lambda(T)) that decrease with heating, reflecting the thermal population of low-lying energy levels of Pr(^{3+}). These results identify PrMgAl(*{11})O(*{19}) as a paradigmatic non-Kramers hexaaluminate where quantum paraelectricity and magnetoelectric interactions are intrinsically entangled, establishing hexaaluminates as a tunable platform for magnetoelectric physics in frustrated quantum materials.

In this note we consider a problem of stochastic optimal control with the infinite-time horizon. We present analogues of the Seierstad sufficient conditions of overtaking optimality based on the dual variables stochastic described by BSDEs appeared in the Bismut-Pontryagin maximum principle.

We report dielectric and magnetoelectric studies of single-crystalline \\ce{CeMgAl11O19}, a Kramers triangular magnet embedded in a polarizable hexaaluminate lattice. In zero magnetic field, the permittivity \\(\\varepsilon'(T)\\) follows the Barrett law of a quantum paraelectric down to 25 K, below which a broad minimum develops near 3 K without evidence of static ferroelectric or magnetic order. Application of magnetic fields up to \\SI{9}{\\tesla} shifts this minimum to higher temperatures and broadens it, evidencing a tunable magnetoelectric response.The magnetoelectric coupling was characterized using results from magnetization measurements. The anomaly temperature \\(T^*\\), extracted from the local minimum of \\(\\varepsilon'(T)\\), exhibits a linear dependence on the squared magnetization \\(M^2\\), consistent with the biquadratic magnetoelectric coupling allowed in centrosymmetric systems. This magnetoelectric effect, mediated by spin-orbit-entangled Kramers doublets interacting with a frustrated antipolar liquid, establishes \\ce{CeMgAl11O19} as a prototype for exploring quantum magnetoelectricity in frustrated systems.

We report broadband dielectric spectra of the non-Kramers hexaaluminate PrMgAl\\textsubscript{11}O\\textsubscript{19}, revealing a pronounced interplay between permittivity and magnetization at cryogenic temperatures. The zero-field dielectric response follows a Barrett-type quantum-paraelectric form, while a broad dielectric anomaly near \\SI{5}{K} shows a complex field dependence that mirrors the multi-hump behavior of the magnetic specific heat, evidencing robust magnetoelectric coupling. The inverse permittivity \\(\\varepsilon'^{-1}(T,H)\\) scales linearly with \\(M^2\\), consistent with a biquadratic \\(P^2M^2\\) term in a Landau framework. Fits yield temperature-dependent coupling constant \\(\\lambda(T)\\) that decreases with heating from (\\(1.07\\pm0.01)\\times10^{-4}\\,\\mu_{\\mathrm{B}}^{-2}\\) (at 5\\,K) to \\((4.77\\pm0.02)\\times10^{-5}\\,\\mu_{\\mathrm{B}}^{-2}\\) (at 10\\,K), reflecting the thermal population of low-lying energy levels of Pr\\(^{3+}\\). Consistently, the uniaxial thermal expansion develops an additional low-temperature hump below \\(\\sim\\SI{30}{K}\\) that is progressively suppressed by magnetic field, recovering an approximately saturated response by \\SI{9}{T}. These results identify PrMgAl\\textsubscript{11}O\\textsubscript{19} as a paradigmatic non-Kramers hexaaluminate where quantum paraelectricity and magnetoelectric interactions are intrinsically entangled, establishing hexaaluminates as a tunable platform for magnetoelectric physics in frustrated quantum materials.