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Structural and chemical insights on the incorporation of americium into zircaloy-derived monoclinic zirconia
No full textMonoclinic zirconia (m-ZrO) forms on the internal surface of nuclear fuel Zircaloy cladding, acting as a critical barrier against radionuclide release at the fuel-cladding interface. However, the incorporation of minor actinide elements like americium in m-ZrO and resultant structural chemistry remains poorly understood. Using a combination of diffraction and high-resolution X-ray spectroscopic techniques, we have examined m-ZrO2 with 5 mol% Am doping. We show Am enters m-ZrO tetravalently, where its solubility is approximately 1.0 mol%, m-(AmZr)O, attributed to the large Am cation, where excess Am, that is predominantly trivalent, adopts a C-type (AmZrx)O phase in space group Ia-3. The known reversible high temperature phase transformation of m-ZrO to tetragonal is further shown to be reduced from 1150 oC to 1050 oC via Am incorporation. The investigation provides critical insight into the chemical reactivity and speciation of minor actinide elements with nuclear fuel cladding related m-ZrO
On the uniqueness of the infinite cluster and the cluster density in the Poisson driven random connection model
No full textWe consider a random connection model (RCM) on a general space driven by a Poisson
process whose intensity measure is scaled by a parameter t ≥ 0. We say that the infinite clusters are deletion stable if the removal of a Poisson point cannot split a cluster in two or more infinite clusters. We prove that this stability together with a natural irreducibility assumption implies uniqueness of the infinite cluster. Conversely, if the infinite cluster is unique then this stability property holds. Several criteria for irreducibility will be established. We also study the analytic properties of expectations of functions of clusters as a function of t. In particular we show that the position dependent cluster density is differentiable. A significant part of this paper is devoted to the important case of a stationary marked RCM (in Euclidean space), containing
the Boolean model with general compact grains and the so-called weighted RCM as special cases. In this case we establish differentiability and a convexity property of the cluster density κ(t). These properties are crucial for our proof of deletion stability of the infinite clusters but are also of interest in their own right. It then follows that an irreducible stationary marked RCM can have at most one infinite cluster. This extends and unifies several results in the literature
Particle Escape from a Potential Well Under High-Frequency External Forcing
No full textThis paper studies the escape dynamics of a periodically forced particle from a potential well. The excitation frequency is assumed to be substantially higher than the natural frequency of the potential well at the stable equilibrium. At this stage, damping is neglected, and the quadratic-quartic Duffing potential oscillator is considered. The paper analyzes two main problems: (i) The escape threshold – for fixed initial conditions (IC), the combinations of the excitation parameters that correspond to the escape transition are determined. (ii) The safe basin – for a given set of excitation parameters, the set of the non-escaping IC is determined. The analytical solution is obtained as a sum of fast and slow components and is compared to the numerical results. The first primary problem is determining the critical forcing amplitude as a function of the excitation frequency. Approximations of the amplitude equation are performed for different phases and zero IC. The results show good correspondence between the numerical and analytical approximations. For the safe basin problem, we analytically demonstrate that the boundary of the non-escaping IC region is a union of two parabolic fragments. In this case, significant discrepancies between the numerical and analytical solutions are identified for extreme forcing values. By analyzing the causes of these differences, we aim to gain a deeper understanding of the dynamics of the Duffing oscillator
Uncertainty-Aware Prognostics of Ball Bearings Using Physics-Based Simulation and Conditional Normalizing Flows
No full textAccurate and uncertainty-aware prediction of the remaining useful life (RUL) of ball bearings is crucial for reliable condition-based maintenance, yet real run-to-failure data are scarce, and most data-driven prognostic models lack calibrated uncertainty estimates. This work proposes a unified framework that combines physics-informed simulation, normalizing-flow-based distribution alignment, and principled uncertainty quantification. A dynamic bearing degradation simulator is used to generate diverse synthetic trajectories, and conditional normalizing flows are employed to align simulated features with real vibration measurements while preserving physically meaningful RUL labels. Deterministic models are trained exclusively on the XJTU-Bearing data set and show good performance, with the best predictor (ExtraTrees) achieving an MAE of 0.0898, an MSE of 0.0113, and an R2 of 0.8658, but lack qualified uncertainty estimates. Building on this base model, we then evaluate several uncertainty-estimation techniques. Quantile regression and conformalized quantile regression reach the nominal 90% (empirical 0.95%) with average interval widths of 0.54, while symmetric conformal prediction attains 0.919 coverage with a width of 0.654. The results demonstrate that combining physics-based simulation with flow-based sim-to-real alignment enables accurate and well-calibrated RUL prediction, even with limited real-world data. The proposed approach offers a scalable foundation for uncertainty-aware predictive maintenance in industrial environments
pid-component v0.3.0
No full textThe pid-component is an easily extensible web component that can be used to display PIDs, DOIs, ORCiDs, RORs and other identifiers in a user-friendly way. It is easily extensible to support other identifier types
Design and synthesis of novel thiazole/1,2,4-triazole/quinoline hybrids as antiproliferative agents, apoptosis inducers, immunomodulators, and multi-EGFR/BRAF/HER-2 inhibitors
No full textWe developed a novel category of quinoline-based compounds that operate as multi-target inhibitors of EGFR, HER-2, and BRAF. The new compounds’ antiproliferative activity was tested against four cancer cell lines. All compounds had GI values ranging from 25 to 76 nM. Compounds 8f, 8k, and 8 m exhibited the most potent antiproliferative action, with 8f and 8k surpassing erlotinib in all evaluated cancer cell lines. 8f and 8k are the most potent multi-target inhibitors of EGFR, HER-2, and BRAF, surpassing the reference EGFR inhibitor, while failing to match the efficacy of Lapatinib and Vemurafenib. We evaluated the apoptotic potential of 8f and 8k, revealing that both compounds induce apoptosis by activating caspase-3, 8, 9, p53, and Bax, while downregulating the expression of Bcl-2, a protein that inhibits apoptosis. An integrated in silico workflow validated docking, 100-ns molecular dynamics (MD), and SwissADME were applied to compound 8f against EGFR, BRAF, and HER-2
First Exclusive Reconstruction of the B, B, and B Mesons and Precise Measurement of Their Masses
No full textUsing proton-proton collision data collected by the CMS experiment at =13 TeV in 2016–2018, corresponding to an integrated luminosity of 140 fb, the first full reconstruction of the three vector meson states, , , and ^{*0}_, is performed. The mass differences between the excited mesons and their corresponding ground states are measured to be ()−()=45.277±0.039±0.027 MeV, ()−()=45.471±0.056±0.028 MeV, and (^{*0}_)−(^0_)=49.407±0.132±0.041 MeV, where the first uncertainties are statistical and the second are systematic. These results improve on the precision of previous measurements by an order of magnitude
Microstructure, phase transformation, and deformation behavior of CuZr martensite
No full textCuZr alloys are promising candidates for advanced structural applications due to their unique martensitic transformations. However, fundamental questions regarding the twinning systems that govern their deformation behavior remain unresolved. Here, through an integrated study of a levitation-melted equiatomic CuZr alloy, we report transformative findings that challenge prior understanding. We present the first experimental evidence of (001) twinning in the primitive B19′ (P2/m) martensite and discover a new, high-shear (111) twin system in the superstructured (Cm) martensite. These results, revealed via transmission electron microscopy and X-ray diffraction, fundamentally expand the known deformation mechanisms in this system. We correlate these specific twin systems directly to the material\u27s macroscopic behavior: reversible (001) and (021) twins facilitate limited plastic strain, while the high-shear (111) twins underpin the observed irreversible deformation and pronounced serrated flow (>1370 MPa) during compression. Furthermore, rapid cooling is shown to kinetically suppress eutectoid decomposition, leading to a higher martensite start temperature (423 K). These insights into twin diversity and phase stability provide a crucial foundation for the rational design of CuZr-based shape memory alloys with tailored mechanical properties
Effects of mHealth interventions to prescribe resistance training: a systematic review and meta-analysis of randomized controlled trials
No full textBackground
This review evaluated the efficacy of resistance training mHealth interventions for improving neuromuscular fitness and resistance training participation. It also explored how resistance training is prescribed through mHealth, and the theoretical frameworks and behavior change techniques (BCTs) employed.
Methods
MEDLINE (OVID), Embase (OVID), Emcare (OVID), SPORTDiscus, Web of Science, Scopus and Cochrane (CINAHL) were searched from January 2010 to February 2025. Randomized controlled trials published in English, targeting adults, that prescribed resistance training via an mHealth platform and measured at least one outcome of neuromuscular fitness or resistance training participation were included.
Results
From the 12,059 records identified, 32 RCTs were included. mHealth-delivered resistance training interventions produced a small, statistically significant improvement in neuromuscular fitness compared with no intervention/usual care (Cohen’s d = 0.18, 95% CI [0.08, 0.28], p < .001, 18 studies). There was a significant, moderate effect for lower body neuromuscular fitness outcomes, but no significant effect for upper body outcomes. Only two studies measured changes to resistance training participation, precluding meta-analysis on this outcome. Studies targeted mostly clinical populations and used mobile applications or websites. Majority of studies included bodyweight exercises, prescribed via videos or pictures, along with text description. Exercise prescription was generally poorly reported across studies. Only 7 studies used a theoretical framework to inform their intervention. All studies incorporated BCTs (17 discrete BCTs used), with a focus on providing instruction and demonstrating behavior.
Conclusions
mHealth is a potentially scalable, effective method of prescribing resistance training. Better reporting of exercise prescription, along with clearer grounding in established theoretical frameworks, is recommended.
Review registration
The review was prospectively registered with the International Prospective Register of Systematic Reviews (PROSPERO; registration number CRD42025641142)