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With the continuous development of economy and industry, the demand for energy in modern society is ever-increasing. As a kind of high efficiency and low carbon energy, nuclear energy has attracted more and more attention. Developing nuclear energy, however, also brings some problems such as the release of radioactive metal ions that pose a threat to the environment and human health. Therefore, separation and removal of radioactive ions(e.g., U(Ⅵ)) from wastewater is of great significance to ensure the sustainable development of nuclear energy. Covalent organic frameworks(COFs) are a kind of periodic porous polymer materials composed of organic molecular units connected by covalent bonds. The emergence of COFs marks a new era in the field of materials. Because of the design ability of COFs and its unique advantages in structure and pore, it shows a good application prospect in catalysis, sensing and adsorption. Very recent efforts by some investigators have focused on the application of COFs in adsorption and separation of radionuclides, generally with encouraging results. According to the classification from the structural dimension, COFs can be divided into two-dimensional COFs materials(2D-COFs) and three-dimensional COFs materials(3D-COFs). Up to now, 2D COFs materials have been widely studied and applied. In contrast, the development of 3D-COF has been relatively slow, and the performance and application have been limited, a result of the limitations of molecular structural units and topological connections, as well as the difficulties of synthesis and structural analysis. To this end, in this paper, a combination of bond transformation and post-grafting was used to construct functional 3D-COFs materials for the efficient removal of U(Ⅵ) from wastewater. Firstly, the imine bond was reduced to an irreversible amine bond by reduction reaction, and then sulfonic acid group was introduced into the skeleton by reaction with 1, 3-propyl sulfonolactone to successfully synthesize COF-320-H2SO3. The structure and properties of COF-320-H2SO3 were characterized by various characterization methods, and the adsorption behavior of COF-320-H2SO3 on U(Ⅵ) was systematically studied. The results show that the chemical stability of COFs is significantly improved by the conversion of imine bond to amine bond, and the adsorption capacity of the material for U(Ⅵ) is clearly enhanced by the introduction of sulfonic acid group with hydrophilic and strong coordination ability. Even under the conditions of 3 mol/L HNO3, the adsorption capacity of U(Ⅵ) can reach more than 40 mg/g. This work further reveals the potential application value of COFs, especially 3D-COFs materials, in the separation of radioactive metal ions.

Abstract Genotoxic therapy triggers reactive oxygen species (ROS) production and oxidative tissue injury. S-nitrosylation is a selective and reversible posttranslational modification of protein thiols by nitric oxide (NO), and 5,6,7,8-tetrahydrobiopterin (BH4) is an essential cofactor for NO synthesis. However, the mechanism by which BH4 affects protein S-nitrosylation and ROS generation has not been determined. Here, we showed that ionizing radiation disrupted the structural integrity of BH4 and downregulated GTP cyclohydrolase I (GCH1), which is the rate-limiting enzyme in BH4 biosynthesis, resulting in deficiency in overall protein S-nitrosylation. GCH1-mediated BH4 synthesis significantly reduced radiation-induced ROS production and fueled the global protein S-nitrosylation that was disrupted by radiation. Likewise, GCH1 overexpression or the administration of exogenous BH4 protected against radiation-induced oxidative injury in vitro and in vivo. Conditional pulmonary Gch1 knockout in mice (Gch1 fl/fl ; Sftpa1-Cre +/− mice) aggravated lung injury following irradiation, whereas Gch1 knock-in mice (Gch1 lsl/lsl ; Sftpa1-Cre +/− mice) exhibited attenuated radiation-induced pulmonary toxicity. Mechanistically, lactate dehydrogenase (LDHA) mediated ROS generation downstream of the BH4/NO axis, as determined by iodoacetyl tandem mass tag (iodoTMT)-based protein quantification. Notably, S-nitrosylation of LDHA at Cys163 and Cys293 was regulated by BH4 availability and could restrict ROS generation. The loss of S-nitrosylation in LDHA after irradiation increased radiosensitivity. Overall, the results of the present study showed that GCH1-mediated BH4 biosynthesis played a key role in the ROS cascade and radiosensitivity through LDHA S-nitrosylation, identifying novel therapeutic strategies for the treatment of radiation-induced lung injury.

Objective To explore the therapeutic effect of transcranial direct current stimulation (tDCS) with different current density on upper limb motor disorder in stroke patients. Methods A total of 45 stroke patients with upper limb motor disorder hospitalized in Xuanwu Hospital, Capital Medical University from March 2019 to June 2022 were selected and randomly divided into low current density stimulation group (low density group, 0.028 mA/cm2), medium current density stimulation group (medium density group, 0.057 mA/cm2), high current density stimulation group (high density group, 0.080 mA/cm2), 15 cases in each group. Upper limb motor function was evaluated by Fugl‑Meyer Assessment Scale for Upper Extremity (FMA‑UE) and Action Research Arm Test (ARAT) before and one week after treatment, and activity of daily living was evaluated by modified Barthel Index (mBI). Results After treatment of tDCS, FMA‑UE (F = 284.343, P = 0.000), ARAT (F = 180.427, P = 0.000) and mBI (F = 487.159, P = 0.000) scores in 3 groups were improved compared with those before treatment. FMA‑UE (F = 2.293, P = 0.000) and ARAT (F = 2.572, P = 0.000) scores were significantly different among 3 groups, FMA‑UE (t = 2.426, P = 0.029; t = 2.140, P = 0.035) and ARAT (t = 2.537, P = 0.024; t = 2.353, P = 0.028) scores in high density group and medium density group were higher than those in low density group. Conclusions tDCS is safe and effective in the treatment of upper limb motor disorder after stroke. Current densities of 0.057 and 0.080 mA/cm2 are more effective than those of 0.028 mA/cm2.

The thermodynamic and transport properties of high-temperature chloride molten salt systems are of great significance for spent fuel reprocessing in the field of nuclear energy engineering. Here, by using machine learning based deep potential (DP) method, we train a high-precision force field model for the LiCl-KCl-LiF system. During force field training, adding new dataset through multiple iterations improves the accuracy of the force field model and its applicability to more configurations. The comparison of density functional theory (DFT) and DP results for the test dataset indicates that our trained DP model has the same accuracy as DFT. Then, we comprehensively investigate the local structure, thermophysical properties, and transport properties of the LiCl-KCl and LiCl-KCl-LiF molten salt systems using the trained DP model. The effects of temperature and LiF concentration on the above properties are analyzed. This work provides guidance for the training of machine learning force fields in molten salt systems and the study of basic physical properties of high-temperature chloride molten salt systems.

The chosen of ligands directly affects the self-assembly behaviors of uranyl compounds, and plays a critical role in the structure and function of the compounds. In this work, several ligands were selected to assembled with uranyl ions by hydrothermal method, and three uranyl coordination polymers(CPs) based on viologen functional groups were synthesized. The main skeleton of the CPs is one-dimensional(1D) chain structure. Among them, compounds 1 and 2 exhibit obvious fluorescence properties. In addition, compound 2 exhibit significantly reversible photochromic/thermochromic properties. Ultraviolet-visible spectrum and electron paramagnetic resonance(EPR) spectrum indicate that the reversible color change is due to the generation of viologen radicals from viologen ligands after irradiation. This research has realized the assembly and synthesis of several uranyl CPs based on viologen ligands, and lead to design and development of more functional materials containing depleted uranium.

The inter-generational participatory co-design project (IPCP) was a theory-guided intergenerational project aiming at eliminating ageism by way of intergenerational contact in an innovative educational experience in higher education. Mixed-method evaluation was adopted with quantitative evaluation conducted before and after the project, supported by post-project individual interviews. Students reported significantly improved attitudes toward older adults (p = 0.042; d = 0.60). Follow-up focus group interviews with students qualitatively examined the factors associated with the improved attitudes toward older adults. The study provides insights for the model of an intergenerational learning experience in tertiary education.

IntroductionThis study investigates the mechanisms linking students’ perceived teacher support with math anxiety, focusing on the mediating roles of the teacher–student relationship and mathematics self-efficacy.MethodsThe research was conducted with 401 fifth-grade students in China, utilizing scales for Students’ Perceived Teacher Support, Teacher–Student Relationship, Math Self-Efficacy, and Math Anxiety.ResultsFindings revealed that student-perceived math teacher support, teacher–student relationship, and math self-efficacy were all significantly negatively correlated with math anxiety. It was notably found that student-perceived math teacher support influenced math anxiety through the chain mediation of teacher–student relationship and math self-efficacy. Additionally, the effect of students’ perceived emotional support from math teachers on math anxiety, mediated by teacher–student relationship intimacy, was significant only among male students.DiscussionThese results underscore the importance of fostering positive teacher–student interactions and enhancing self-efficacy to reduce math anxiety among primary school students. The gender-specific findings regarding emotional support and relationship intimacy highlight the need for tailored strategies in addressing math anxiety.

From a coordination chemistry perspective, we aimed to advance the knowledge of Sr/Cs separation in the scheme of spent nuclear fuel reprocessing. Based on data mining of crystal structures and deep learning architecture, we summarized and analyzed coordination chemistry properties of Sr/Cs from complex structures(ca. 3.3×104 samples) of 8 alkaline and alkaline earth elements, especially focusing on coordination bond lengths as a representative figure of merit. Applying a Bayesian optimization approach, we were able to establish a high-performing transformer model which could predict the(differential) coordinative affinities toward Sr/Cs of ligand molecules, with exceptional accuracy. As a proof-of-concept, we systematically analyzed ca. 9.1×103 ligand molecules in terms of potential coordinative selectivity toward Sr/Cs and ranked them. In addition, we also determined different contribution of various functional groups for future molecular design of ligands with selectivity. The present study presented fundamental knowledge for coordination chemistry information in the context of radiochemistry and spent nuclear fuel reprocessing, provided guidance and reference for subsequent experiments regarding Sr/Cs separation.

The physical and chemical properties of transplutonium elements are very similar, and their in-group separation is extremely difficult. It is generally believed that the oxidation state of transplutonium elements is usually +3, and their properties are similar to lanthanides. However, related studies in recent years have found that some Bk, Cf compounds have stronger covalent interactions than Pu, Am, Cm compounds. Since transplutonium elements are high toxicity, strong radioactivity and mostly short-lived nuclides, experimental studies are very difficult, and relevant experimental data are particularly scarce. In recent years, theoretical calculations have become an important means to understand the physical and chemical properties of transplutonium elements. In this review, we summarize recent theoretical advances in the bonding nature of transplutonium(Am, Cm, Bk, Cf) compounds.

Introduction Both cigarette smoking and gut microbiota play important roles in colorectal carcinogenesis. We explored whether the association between smoking and colorectal cancer (CRC) risk varies by gut microbial enterotypes and how smoking-related enterotypes promote colorectal carcinogenesis. Methods A case-control study was conducted. Fecal microbiota was determined by 16S rDNA sequencing. The cases with CRC or adenoma were subclassified by gut microbiota enterotypes. Multivariate analyses were used to test associations between smoking and the odds of colorectal neoplasm subtypes. Mann-Whitney U tests were used to find differential genera, genes, and pathways between the subtypes. Results Included in the study were 130 CRC patients (type I: n=77; type II: n=53), 120 adenoma patients (type I: n=66; type II: n=54), and 130 healthy participants. Smoking increased the odds for type II tumors significantly (all p for trend

Abstract Radiotherapy resistance is an important and urgent challenge in the clinical management of esophageal squamous carcinoma (ESCC). However, the factors mediating the ESCC resistance to radiotherapy and its underlying molecular mechanisms are not fully clarified. Our previous studies have demonstrated the critical role of DNA polymerase iota (POLI) in ESCC development and progression, here, we aimed to investigate the involvement of POLI in ESCC radiotherapy resistance and elucidate the underlying molecular mechanism. We found that highly expressed POLI was correlated with shorter overall survival of ESCC patients received radiotherapy. Down-regulation of POLI sensitized ESCC to IR, prolonged γH2AX foci in nuclei and comet tails after IR. HR but not NHEJ repair is inhibited in POLI-deficient ESCC cells. POLI stabilizes RAD51 protein via competitively binding with and blocking the interaction between RAD51 and E3 ligase XIAP and XIAP-mediated ubiquitination. Furthermore, loss of POLI leads to the activation of GAS signaling. Our findings provide novel insight into the role of POLI in the development of radioresistance mediated by stabilizing RAD51 protein in ESCC.

This study focuses on the recognition and isolation of fullerenes, which are crucial for further exploration of their physical and chemical properties. Our goal is to investigate the potential recognition of the D5h–C70 fullerene using crown-shaped metal compositions through density functional theory calculations. We assess the effectiveness of fullerene C70 recognition by studying the binding energy. Additionally, various analyses were conducted, including natural bond order charge analysis and reduced density gradient analysis, to understand the interaction mechanism between the host and guest molecules. These investigations provide valuable insights into the nature of the interaction and the stability of the host–guest system. To facilitate the release of the fullerene guest molecule, the vis–NIR spectra were simulated for the host–guest structures. This analysis offers guidance on the specific wavelengths that can be utilized to release the fullerene guest from the host–guest structures. Overall, this work proposes a new strategy for the effective recognition of various fullerene molecules and their subsequent release from host–guest systems. These findings could potentially be applied in assemblies involving fullerenes, advancing their practical applications. [ABSTRACT FROM AUTHOR]