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2025
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2025
Abstract
For successfully heating plasma with waves in the Ion Cyclotron Range of Frequencies (ICRF), mitigating impurity production is just as crucial as maximizing power coupling, especially in high-Z environments [Urbanczyk 2021]. Only when the power is coupled with limited influence on impurity production, can ICRF truly become a powerful tool to directly deposit energy on ions, modify turbulence-driven transport and enhance the efficiency of fusion reactions. 
To do so, one must rely on a toroidal array of at least three active elements excited with appropriate phasing and power ratio to reduce the currents induced on the antenna frame below levels critical for physical sputtering. In contrast with classic 2-strap antennas which work best when operated in dipole phasing with same power on both straps, 3-strap antennas in ASDEX Upgrade (AUG) – but also 4-strap antennas in JET, Alcator C-Mod, SPARC and ITER – offer the possibility to also act on the power ratio between central and outer straps. With optimal settings, impurity production can be reduced substantially, making ICRF compatible with high-Z wall [Bobkov 2017]. 
This paper explores the characteristics of the AUG 3-strap antennas in terms of impurity production, as well as the key role of plasma composition in this process. It is shown that the experimentally measured energies of ions falling on antenna limiters can well be predicted with at least two different numerical tools: SSWICH and Petra-M. These tools are further used to describe the source of impurity, namely the gross erosion of tungsten from an ICRF antenna for different plasma mixtures, and results of the calculations are compared to experiments. We finally show that deleterious effects of ICRF on plasma surface interactions will be weaker in plasmas containing larger fractions of highly ionized heavier low-Z impurity, which is typically relevant for experiments relying on impurity seeding.- Book : ()
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2025
- Book : ()
- Pub. Date : 2025
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2025
The review presents general information about the tumor cell microenvironment, its role in the development and progression of the malignant process and the results of antitumor therapy. The analysis showed that the development of methods for influencing the key metabolic targets of tumor cells and their microenvironment is a promising direction in experimental and clinical oncology. Some approaches to inducing metabolic modulation are considered: inhibitors of cellular pumps, hyperglycemia and hyperthermia. The therapeutic effect of the first two induction options is based on modulation of the acid-base balance (pH) of the tumor. The biological effect of hyperthermia is broader and directly depends on the severity and direction of the temperature-exposure mode of heating. Ultimately, such changes lead to an increase in the damaging effect of ionizing radiation and drugs on the tumor. Despite the fact that the composition of the microenvironment is heterogeneous and varies depending on the type of tumor, some specific cells and mediators are present in all its types. Therefore, the developed treatment methods can be universal for most tumor locations.- Book : ()
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2025
- Book : ()
- Pub. Date : 2025
- Page : pp.100876-100876
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2025
ABSTRACT
Cardiac computed tomography (CT) has evolved significantly as a critical tool in diagnosing and managing cardiac diseases, greatly facilitated by technological advancements in multidetector systems, dose-reduction techniques, and sophisticated imaging algorithms. This article discusses the historical progression and technological evolution in cardiac CT (CCT), focusing on the impact of 64-multidetector row CT and dual-energy CT systems on improving spatial and temporal resolutions and reducing radiation exposure. It explores the role of these technologies in enhancing diagnostic accuracy, such as through detailed three-dimensional reconstructions and minimized imaging artifacts. Furthermore, it highlights the integration of machine learning to automate complex imaging analysis and photon-counting CT, which promises higher resolution and further dose reduction. Prospective studies and ongoing trials such as FASTTRACK coronary artery bypass grafting also underscore the potential of advanced CT technologies in refining procedural planning and execution. The continuous advancements in detector technology, computational techniques, and image reconstruction are poised to expand the applications and efficacy of CCT, cementing its role in modern cardiology.- Book : ()
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2025
AbstractAtomic‐level designed electrocatalysts, including single‐/dual‐atom catalysts, have attracted extensive interests due to their maximized atom utilization efficiency and increased activity. Herein, a new electrocatalyst system termed as “atomic symbiotic‐catalyst”, that marries the advantages of typical single‐/dual‐atom catalysts while addressing their respective weaknesses, was proposed. In atomic symbiotic‐catalyst, single‐atom MNx and local carbon defects formed under a specific thermodynamic condition, act synergistically to achieve high electrocatalytic activity and battery efficiency. This symbiotic‐catalyst shows greater structural precision and preparation accessibility than those of dual‐atom catalysts owing to its reduced complexity in chemical space. Meanwhile, it outperforms the intrinsic activities of conventional single‐atom catalysts due to multi‐active‐sites synergistic effect. As a proof‐of‐concept study, an atomic symbiotic‐catalyst comprising single‐atom MnN4 moieties and abundant sp3‐hybridized carbon defects was constructed for low‐temperature zinc‐air battery, which exhibited a high peak power density of 76 mW cm−2 with long‐term stability at −40 °C, representing a top‐level performance of such batteries.- Book : ()
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2025
ABSTRACTIn the present study, an interconnected photovoltaic‐thermal system and solar thermal collector with half‐tubes are presented as a new generation of solar systems to produce maximum thermal and electrical power. Performance comparison of the photovoltaic module, photovoltaic‐thermal system, solar thermal collector, and proposed system shows that the maximum power of 1336.27 W is generated by the proposed system. Also, the outlet fluid temperature increases by 28.03% and 20.88% compared to the photovoltaic‐thermal systems and solar thermal collectors, respectively, which indicates higher quality of the generated thermal power. To improve the system performance, fins with different heights are used inside the half‐tubes. The results indicated that the overall generated power increases using the fin by up to 2.93%. A parametric analysis using response surface method showed that among four parameters including flow rate, incident solar radiation, wind speed, and ambient temperature, the solar radiation and ambient temperature have the most and least impact on the system output, respectively. Also, using the response surface method, two models are provided to predict the electrical and thermal power generation of the system. Single‐objective and multi‐objective optimization of the system is also investigated using these models.- Book : ()
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2025
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- Pub. Date : 2025
- Page : pp.1-1
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2025
AbstractCurrent diagnostics for sepsis‐associated acute kidney injury (SA‐AKI) detect kidney damage only at advanced stages, limiting opportunities for timely intervention. A DNA origami‐based nanoplatform is developed for the early diagnosis and treatment of SA‐AKI. Modified with a fluorophore (Cy5) and quencher (BHQ3), the DNA origami remains nonfluorescent under normal conditions. During SA‐AKI, elevated microRNA‐21 triggers a strand displacement reaction that restores the fluorescence signal, enabling real‐time detection. Additionally, the photoacoustic changes of BHQ3, driven by different excretion rates of the nanostructure and released DNA strands, enable dual‐mode imaging, enhancing diagnostic accuracy. Therapeutically, DNA origami scavenges reactive oxygen species and, when conjugated with the antimicrobial peptide Leucine‐Leucine‐37 (LL‐37), exhibits bactericidal effects. This combination boosts survival rates by 80% in SA‐AKI models. This dual‐response nanoplatform integrates precise imaging and targeted therapy, offering a powerful strategy for SA‐AKI management and advancing applications of DNA origami in precision nanomedicine.- Book : ()
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