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Advanced skin cancer prediction with medical image data using MobileNetV2 deep learning and optimized techniques
Vibronic spectrum of pyrazine: New insights from multi-state-multi-mode simulations parameterized with equation-of-motion coupled-cluster methods
This study reports simulations of the lowest band in the electronic absorption spectrum of pyrazine carried out using a multi-state-multimode vibronic Hamiltonian parameterized using equation-of-motion coupled-cluster methods. The simulations explain the main spectral features and show how peaks of vibronic nature appear. The most complete vibronic model includes four electronic states and six vibrational modes. The simulations reveal that non-adiabatic coupling with bright states located as high as 3 eV above the studied state can lead to discernible features in the absorption spectrum. This study demonstrates the power of fully ab initio treatments of electronic and vibrational structure and their utility in understanding the mechanisms leading to complex molecular spectra.
Explainable illicit drug abuse prediction using hematological differences
Mitigating error cancellation in density functional approximations via machine learning correction
The integration of machine learning (ML) with density functional theory has emerged as a promising strategy to enhance the accuracy of density functional methods. While practical implementations of density functional approximations (DFAs) often exploit error cancellation between chemical species to achieve high accuracy in thermochemical and kinetic energy predictions, this approach is inherently system-dependent, which severely limits the transferability of DFAs. To address this challenge, we developed a novel ML-based correction to the widely used B3LYP functional, directly targeting its deviations from the exact exchange-correlation functional. By utilizing highly accurate absolute energies as exclusive reference data, our approach eliminates the reliance on error cancellation. To optimize the ML model, we attribute errors to real-space pointwise contributions and design a double-cycle protocol that incorporates self-consistent field calculations into the training workflow. Numerical tests demonstrate that the ML model, trained solely on absolute energies, improves the accuracy of calculated relative energies, demonstrating that robust DFAs can be constructed without resorting to error cancellation. Comprehensive benchmarks further show that our ML-corrected B3LYP functional significantly outperforms the original B3LYP across diverse thermochemical and kinetic energy calculations, offering a versatile and superior alternative for practical applications.
Association between gastroesophageal reflux disease and DMFT index in the PERSIAN Guilan Cohort Study
The mutagenic forces shaping the genomes of lung cancer in never smokers
Quantitation of the piezoelectric coefficients of room temperature ionic liquids
We report the development of a means to quantitatively evaluate the piezoelectric coefficient, d33, of room temperature ionic liquids (RTILs) and apply it to investigate how d33 varies with RTIL cation structure. The d33 quantitation method we developed also enables evaluation of the average size of pressure-induced, piezoelectrically active RTIL crystals. We evaluated d33 for RTILs composed of seven different cations and the common anion bis(trifluoromethylsulfonyl)imide (TFSI−) and found that its magnitude varies predictably with the extent of conjugation and the length of the cation’s aliphatic chain. These findings offer insights into how the constituent ion structures of RTILs can be rationally optimized to enhance piezoelectric activity.
Analysis of data on biosimilar prescription rates in rheumatology practice from a reference center in Turkey
Vibrational energy flow in adenosine triphosphate
Intermolecular vibrational energy transfer from H2O to adenosine triphosphate (ATP) molecules and intramolecular energy redistribution in ATP have been studied using the semiclassical Wentzel–Kramers–Brillouin procedure and quasiclassical trajectory calculations. The hydrogen bond interaction between the excited vibrational stretches of H2O (symmetric stretching mode in v = 1) and OH vibration of the γ-phosphate of the ground state ATP leads to efficient intermolecular energy flow, which is followed by intramolecular energy distribution in ATP. The phosphorus–oxygen chain functions as an efficient pathway for energy distribution to the ribose moiety and then ultimately to the terminal stretches of the adenine moiety, distributing most of the available energy to high-frequency OH, CH, and NH bonds on a sub-picosecond scale, while the hydrogen bond maintains its lifetime of ∼2 ps.
An investigation into the spatial patterns of invasive common milkweed (Asclepias syriaca L.) stands through the utilization of drone images
Abstract The phenomenon of biological invasions represents one of the most significant threats to biodiversity. A fundamental aspect of combating invasive plant species is the comprehension of the spatial and temporal alterations in their population dynamics. One of the important habitats of the European Union is the Pannon sand grasslands in Hungary, which are primarily threatened by the invasive common milkweed (Asclepias syriaca). The objective of this study was to ascertain the efficacy of drone imaging in examining the spatial patterns of milkweed shoots in comparison to ground survey data. To facilitate comparison, a survey was conducted on 12 milkweed populations in the Fülöpháza area of Kiskunság National Park. In each population, a 12-meter transect (comprising six contiguous 2 m × 2 m quadrats) was designated within which the positions of the shoots were recorded with centimeter accuracy through ground surveys. The individual shoots were marked on images captured from an altitude of 20 m using a drone. The results indicated that the number of shoots identified in the drone images was slightly lower than in the ground surveys; however, a positive correlation was observed between the two datasets (r = 0.9594). A strong positive correlation was evident between the ground and drone surveys in terms of both the average distance between shoots and the observed pattern (r = 0.933 and r = 0.9146). In light of these findings, it can be concluded that drone imaging represents an effective method for examining the size and pattern of populations. Consequently, it may prove to be a valuable tool for the accurate planning of invasive species management in conservation efforts and the monitoring of the effectiveness of treatments.
Fluctuations of driven probes reveal nonequilibrium transitions in complex fluids
Complex fluids subjected to localized microscopic energy inputs, typical of active microrheology setups, exhibit poorly understood nonequilibrium behaviors because of the intricate self-organization of their mesoscopic constituents. In this work, we show how to identify changes in the microstructural conformation of the fluid by monitoring the variance of the probe position, based on a general method grounded in the breakdown of the equipartition theorem. To illustrate our method, we perform large-scale Brownian dynamics simulations of an effective model of micellar solution and we link the different scaling regimes in the variance of the probe’s position to the transitions from diffusive to jump dynamics, where the fluid intermittently relaxes the accumulated stress. This suggests that stored elastic stress may be the physical mechanism behind the nonlinear friction curves recently measured in micellar solutions, pointing at a mechanism for the observed multi-step rheology. Our approach overcomes the limitations of continuum macroscopic descriptions and introduces an empirical method, applicable in experiments, to detect nonequilibrium transitions in the structure of complex fluids.
Parental social environment has transgenerational effects on zebrafish (Danio rerio) growth
The state-dependence of the diffusion-controlled transport: Transitions and relaxations
The transport through a medium is primarily identified with the rate of the process and population densities inside it. The environmental conditions, such as the viscosity and temperature of the system, effectively the diffusion coefficients, govern stochastic transports. In addition, the structure of the potential characterizing the medium plays a crucial role in determining the key features of the transitions and relaxations. Here, we explore the importance of detailed information about the medium of transport in terms of the diffusion coefficient and the position of the reference point at which the rate is measured. Our study reveals that the varying positions of the states considered and the diffusion coefficient characterizing them have significant impacts on the integrated understanding of the kinetics of the diffusion-limited processes. We consider the left-to-right well transition in a double-well potential. We vary the location of the reference point systematically in the right well to measure the state-dependent rate. Interestingly, we observe that the rate exhibits a power-law relation with the distance from the barrier top. Another important perspective of our study is to consider varying diffusion coefficients for the two wells to account for the state-dependent fluctuations and explore their effects in the determination of rates of the transport processes. The observations reveal some critical aspects regarding the fundamental roles of the originating and target states in transport. The results of the current study not only enrich the elemental understanding of diffusion-controlled kinetics but also indicate the paths in developing advantageous technologies based on optimizing the conditions of transport.
Statistical inference and applications of a new transforming weibull distribution
Three-photon quantum cutting infrared emission based on two-step energy transfers in Er3+ doped bi-perovskite Ca2ScSbO6 phosphors: Mechanism and efficiency
Quantum cutting (QC) materials still attract significant attention due to their high quantum and energy efficiencies, which stem from the effective utilization of the excitation energy. In this study, a one-to-three QC 1544 nm emission was first developed in an Er3+ single-doped Ca2ScSbO6 phosphor system. The Ca2ScSbO6 host was selected since it possesses moderate maximum-phonon energy, which suppresses non-radiative relaxation while maintaining phonon-assisted energy transfers between Er3+ ions. Spectroscopic measurements elucidated the QC mechanisms that two-step energy transfers, including ET1: 4S3/2(2H11/2) + 4I15/2 → 4I9/2 + 4I13/2 and ET2: 4I9/2 + 4I15/2 → 4I13/2 + 4I13/2 processes, are responsible for the three-photon generation. The radiative transitions, non-radiative relaxations, and energy transfers of pertinent levels were taken into consideration when calculating the QC efficiencies for Er3+ doped Ca2ScSbO6 phosphors with varying Er3+ concentrations. The concerned radiative transition rates of Er3+ in Ca2ScSbO6 were calculated in the framework of Judd–Ofelt theory, while the non-radiative transition rates were derived based on the energy gap law. The maximum energy transfer efficiencies for ET1 and ET2 were determined to be 99% and 93%. Finally, the QC efficiencies for Er3+ doped Ca2ScSbO6 phosphors were calculated, and the maximum value was confirmed in the 20 mol. % Er3+ doped sample to be 232%. The primary reason for the deviation of the QC efficiencies from the theoretical maximum value of 300% was attributed to the fluorescence self-quenching of Er3+.
Inducing memristive behavior to MoSe2/graphene bilayer using plasma treatment
Oriented composition fluctuation domains of a two-dimensionally confined critical Ising fluid
A quasi-binary two-dimensional Ising critical system with the main components D2O and butyric acid confined by surfactant layers has been studied. The surfactant forms large planar layers and is the basis of the charge density waves with wave fronts aligned with the layers. To orient the domains in an external magnetic field, thulium ions were added to the system (replacing sodium in the surfactant with thulium and adding more TmCl3). The critical behavior of the forward scattering and the correlation length were observed to be more mean-field-like. This can be explained by the presence of the trivalent thulium ions mediating between water and butyric acid. The high-Q scattering could be distinguished in the different directions and the ideal two-dimensional critical composition fluctuation exponent ηxy = 1/4 was observed, while the other exponent ηz = −0.08 ± 0.06 was slightly negative due to a finite acceptance angle and the finite magnetic field. The orientationally averaged high-Q exponent x of this study is well-explained by ηxy = 1/4 of the two-dimensional Ising behavior and ηz = 0.
Evaluation of the quality and reliability of Chinese content about orthognathic surgery on BiliBili and TikTok: a cross-sectional study
Sound attenuation in glasses
Comprehending sound attenuation is integral to understanding the anomalous low temperature properties of glasses. Despite decades of studies, the underlying mechanism of sound attenuation in glasses is still debated. In this perspective, we review recent work on sound attenuation in amorphous solids. We focus on the role of defects and heterogeneous elasticity, and we also discuss attenuation in model amorphous solids without defects. We review our definition of attenuation defects and show that they strongly influence sound attenuation. However, we also find another contribution to sound attenuation that cannot be attributed to attenuation defects. We confirm an earlier result of Kapteijns et al. [Kapteijns et al., J. Chem. Phys. 154, 081101 (2021)] that heterogeneous elasticity theory predicts relative changes of sound attenuation in model two-dimensional glasses if the configuration-to-configuration elastic constants fluctuations are used to quantify the heterogeneity. We extend this finding to similar three-dimensional glasses. We end by discussing the Euclidean random matrix model, which exhibits Rayleigh scaling of sound attenuation but does not have quasi-localized excitations and, thus, probably does not have sound attenuation defects. We propose that the mechanisms behind sound attenuation can be more fully understood by approaching the problem from two directions: one where the strong influence of defects is studied and another where sound attenuation is studied in defect free, although disordered, materials.