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Based on the Monte Carlo homogenization theory and the finite volume method, a three-dimensional diffusion spatiotemporal dynamics model suitable for the analysis of instantaneous critical accidents was established. The three-dimensional diffusion spatiotemporal dynamics model was coupled with the unsteady state heat transfer model and the radiation cracking bubble model, and the calculation program GETAC-S was upgraded, so that GETAC-S had the ability to analyze the transient state of the solution system under any geometric and material conditions. GETAC-S was verified by the experimental data of TRACY, which was an international transient device, and the results are in good agreement. GETAC-S was used to invert the process of JCO criticality accident in Japan, and the results show that the GETAC-S has the ability to evaluate and retrieve the consequences of critical accidents in complex solution system, which provide theoretical support for the prevention, evaluation and shielding of nuclear critical accidents.

Based on the design requirements of the first stage of the China Fusion Engineering Test Reactor (CFETR), the activation performance calculation and analysis of the components in the dual function lead-lithium blanket were performed using a neutron transport design and safety evaluation software system (SuperMC) with the fusion evaluation database JEFF3.2. A coupled burnup and transportation calculation method was used to calculate the radioactivity, residual decay heat, dose rate, and potential biological hazards of each component in the equatorial surface of the fusion reactor at different times after shutdown. The waste disposal problem of the tritium breeding blanket after the decommissioning of the fusion reactor was analyzed according to the relevant nuclear waste disposal standards in the safety and environment assessment of fusion power strategy. Results of the analysis show that under the condition of normal operation of 200 MW for 10 years, all components of the breeding blanket in the CFETR can satisfy simple recycling standards and meet the requirements of the first stage of CFETR radioactive waste treatment after 50 a of cooling.

Docetaxel (Doc) plays a crucial role in clinical antineoplastic practice. However, it is continuously documented that tumors frequently develop chemoresistance and relapse, which may be related to polyploid giant cancer cells (PGCCs). The aim of this study was investigate the formation mechanism and biological behavior of PGCCs induced by Doc. Ovarian cancer cells were treated with Doc, and then the effect of Doc on cellular viability was evaluated by MTT assay and microscopic imaging analysis. The biological properties of PGCCs were further evaluated by Hoechst 33342 staining, cell cycle and DNA content assay, DNA damage response (DDR) signaling detection, β-galactosidase staining, mitochondrial membrane potential detection, and reverse transcription-quantitative polymerase chain reaction. The results indicated that Doc reduced cellular viability; however, many cells were still alive, and were giant and polyploid. Doc increased the proportion of cells stayed in the G2/M phase and reduced the number of cells. In addition, the expression of γ-H2A.X was constantly increased after Doc treatment. PGCCs showed senescence-associated β-galactosidase activity and an increase in the monomeric form of JC-1. The mRNA level of octamer-binding transcription factor 4 (OCT4) and krüppel-like factor 4 (KLF4) was significantly increased in PGCCs. Taken together, our results suggest that Doc induces G2/M cell cycle arrest, inhibits the proliferation and activates persistent DDR signaling to promote the formation of PGCCs. Importantly, PGCCs exhibit a senescence phenotype and express stem cell markers. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) have stimulated extensive attention due to their environmental friendliness and low cost. Unfortunately, the inevitable dendrite growth and corrosion on the zinc (Zn) anode severely hinder the practical application of AZIBs. Herein, an amino acid containing an imidazole group is introduced as an effective additive to address these issues. The dynamic conversion of amino acid and protonated amino acid creates a pH buffer function that regulates solution pH in real time, inhibits hydrogen evolution reaction (HER), and eliminates notorious by‐products. In addition, the protonated amino acid is preferentially adsorbed on the Zn anode, preventing contact of the active water with the Zn surface and promoting homogeneous Zn deposition. Thus, the amino acid‐based electrolyte promotes dendrite free plating/stripping with a Coulombic efficiency up to 99.67% and cycle lifetime of 2600 h. In particular, a depth of discharge of up to 87% can be achieved with an ultra‐high areal capacity of 24 mAh cm−2. The developed Zn||CVO full cell also exhibits better electrochemical performance than that without additives. This work provides an effective and convenient approach for safe and efficient Zn‐ion batteries. [ABSTRACT FROM AUTHOR]

The kinetics and durability of conversion‐based anodes greatly depend on the intrinsic stress regulating ability of the electrode materials, which has been significantly neglected. Herein, a stress dissipation strategy driven by multi‐interface built‐in electric fields (BEFs) and architected structure, is innovatively proposed to design ultrafast and long‐term sodium ion storage anodes. Binary Mo/Fe sulfide heterostructured nanorods with multi‐interface BEFs and staggered cantilever configuration are fabricated to prove our concept. Multi‐physics simulations and experimental results confirm that the inner stress in multiple directions can be dissipated by the multi‐interface BEFs at the micro‐scale, and by the staggered cantilever structure at the macro‐scale, respectively. As a result, our designed heterostructured nanorods anode exhibits superb rate capability (332.8 mAh g−1 at 10.0 A g−1) and durable cyclic stability over 900 cycles at 5.0 A g−1, outperforming other metal chalcogenides. This proposed stress dissipation strategy offers a new insight for developing stable structures for conversion‐based anodes. [ABSTRACT FROM AUTHOR]

Aiming at the problem of unstable output voltage and rapid reduction of efficiency caused by coil misalignment in the wireless charging process of wireless chargers, a hybrid wireless power system with anti-misalignment and constant current (CC) output characteristics is proposed. The system uses a high-order compensation network and a four-coil bipolar (BP) coupler to implement high anti-misalignment and CC output characteristic that is decoupled from the load. By inserting a high-order compensation network, the two overlapping coils in the same side of the transmitter and receiver sides of the BP coupler can be effectively decoupled and the design methodology can be simplified. Moreover, by adjusting the inductance value of the transmitter compensation network, the BP coupler can be made available for the occasions with different equivalent mutual inductance (MI) fluctuation requirements. While the receiver coil is suddenly removed, the system has a self-protection function, which can effectively limit the current flowing through the inverter. The design ideas of the coupler and compensation network are also discussed in this paper. Ultimately, a 1-kW experimental prototype is built to validate the proposed scheme. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is one of the most prevalent forms of dementia in older individuals. Convergent evidence suggests structural connectome abnormalities in specific brain regions are linked to AD progression. The biological basis underpinnings of these connectome changes, however, have remained elusive. We utilized an individual regional mean connectivity strength (RMCS) derived from a regional radiomics similarity network to capture altered morphological connectivity in 1654 participants (605 normal controls, 766 mild cognitive impairment [MCI], and 283 AD). Then, we also explored the biological basis behind these morphological changes through gene enrichment analysis and cell‐specific analysis. We found that RMCS probes of the hippocampus and medial temporal lobe were significantly altered in AD and MCI, with these differences being spatially related to the expression of AD‐risk genes. In addition, gene enrichment analysis revealed that the modulation of chemical synaptic transmission is the most relevant biological process associated with the altered RMCS in AD. Notably, neuronal cells were found to be the most pertinent cells in the altered RMCS. Our findings shed light on understanding the biological basis of structural connectome changes in AD, which may ultimately lead to more effective diagnostic and therapeutic strategies for this devastating disease. [ABSTRACT FROM AUTHOR]

This study offers a systematic review of the research on the treatment of waste household appliances in China in the past 20 years. A total of 1123 related articles were selected from the CNKI database from 1998 to 2020 to sort out the hot spots, evolution and frontier trends. The results show that: (1) In the past 20 years, the research on waste household appliances in China has followed the development path of “society-technology-human”, gradually evolving from the macro level to the micro level, and the research in the field of waste household appliances governance has begun to take shape. (2) With the increasing enrichment of research methods and the continuous expansion of research ideas, the research topic breaks through the boundaries of single theory and discipline, and reverse logistics, closed-loop supply chain, recycling behavior, recycling and dismantling technology, etc. have become research hotspots. (3) From the initial study of the management experience of developed countries to the study of recycling management with Chinese characteristics, China’s “Internet + recycling” model is ahead of the international level and has become the latest research hotspot.