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The novel Ni–Cr–W–Gd alloy have the gadolinium neutron absorption unit and the tungsten gamma ray shielding unit, which can be used for thermal neutron and gamma ray co-shielding. This Ni–Cr–W–Gd alloy have good strength and fracture elongation, however, its corrosion performance has not been reported yet. In this work, the corrosion behavior for Ni–Cr–W–Gd alloys was studied in the boric acid solution at 40 °C. Electrochemical measurement techniques, long-term immersion tests, corrosion morphology and composition analysis, and first principles calculation have been used. After 4000 h immersing, the maximum steady state corrosion rate among all alloys is only 0.3221 μm/yr. The increasing Gd promotes the increase in corrosion current density and make the weight loss of alloys more serve. Both the results of relative potential test and first principles calculation demonstrate the NiCrW matrix is the anode and Ni5Gd is the cathode in micro galvanic corrosion. The matrix around the interface of matrix/Ni5Gd suffer preferential anodic dissolution, resulting in the detachment of the Ni5Gd phase and formation of pores on the surfaces. The passive films are composed of Cr2O3 and WO3, moreover, the intensity of Gd2O3 increases with Gd content. This work contributes to the promotion of the novel alloys in spent fuel storage environments.

In this paper, a novel mono-methacrylated β-cyclodextrin (β-CD) monomer mediated by disulfide bond was synthesized, and then thermal copolymerized with HEMA monomer in the presence of a little crosslinker to prepare redox-responsive hydrogel for regulated drug delivery. The structure of the monomer was confirmed by FTIR, 1H NMR, 13C NMR spectroscopy. The substitution degree of polymerizable methacrylated group grafted onto β-CD was about 1 by calculating by1H NMR (0.987) and element analysis (0.937). The mono-methacrylated β-CD monomer can well copolymerize with 2-hydroxyethyl methacrylate (HEMA) monomer with gel fraction over 80%. The hydrogel shows low cytotoxicity, and copolymerization of the mono-methacrylated β-CD monomer in the hydrogels increases its equilibrium swelling degree (ESD) and tensile strength, while its transmittance slightly decreases. Drug loading and release rate are dependent on the β-CD content. The hydrogel with high β-CD content of 13.83 wt% shows 1.8 and 8.5 folds puerarin (PUE) and curcumin (CUR) loading than pure pHEMA hydrogel, respectively. The incorporation of β-CD sustained drug release, especially CUR release was prolonged more than 24 h from 5 h of pure pHEMA hydrogel (80% release). The hydrogels are highly sensitive to reduced glutathione (GSH), and low concentration of GSH of 3 mM can significantly accelerate drug release rate. The higher of β-CD content, the more sensitive the hydrogels to GSH, resulting in rapider drug release rate.

Background: More than half the domestic population in China were infected with COVID-19 in two months after ending “zero-infection policy”, which severely overwhelmed frontline healthcare providers with stress and fear. However, there is no study to date investigating the associations between nurses' fear of pandemic and cyberchondria. This study aimed to 1) investigate the correlations between fear pandemic and cyberchondria among frontline nurses, and 2) discover its potential mechanism. Methods: A cross-sectional sample of frontline nurses (N = 8161) was recruited from 98 hospitals across China in February 2023. Participants were invited to complete an online, self-rated standardized questionnaire focused on pandemic fear, alexithymia, psychological distress, and cyberchondria. Environmental, clinical and socioeconomic information were collected for adjustment while conducting chain mediation analysis. Results: When other covariates were controlled, it was found that fear of the pandemic significantly contributed to cyberchondria (b = 0.58, 95%CI [0.56, 0.60], p

IntroductionVitamin K deficiency may elevate the incidence of musculoskeletal disorders (MSD), whereas it lacks validation for pediatric populations and has uncertain dose recommendations. In this context, we hypothesized that serum vitamin K levels are associated with MSD in preschool children, and the widely used vitamin A and vitamin D supplements may mediate these associations based on potential mechanisms, which expects to provide guidance for future practice.MethodsA cross-sectional study was conducted in Sichuan province in southwestern China, from January 2021 to May 2022. Serum levels of vitamin K1/K2 and 25(OH)D were determined using the high-performance liquid chromatography method, and the diagnosis of MSD was executed by clinicians. Overall and stratified logistic regression analysis based on categorized 25(OH)D levels were conducted to assess association between serum vitamin K levels and MSD prevalence after adjusting for confounders. Mediation analysis was further performed and vitamin A and D supplementation was regressed as the mediator.ResultsA total of 6,368 children aged 0–6 years old were enrolled. MSD was identified in 1179 (18.51%) of the children, while 5,189 (81.49%) of them did not present such disorder. After adjusting confounders, a significant difference was found in serum vitamin K1 level between children in MSD and Non-MSD group (OR = 0.802, 95%CI 0.745–0.864). No significant difference was found in serum vitamin K2 level between the two groups (OR = 0.975, 95%CI 0.753–1.261). The association between vitamin K1 level and MSD prevalence was partly (36.8%) mediated by vitamin A and D supplementation.ConclusionsA low serum vitamin K1 level is connected with an increased risk of MSD among children, highlighting that vitamin A and D supplementation is a helpful intervention to prevent MSD in children with vitamin K deficiency.

Abstract Purpose The primary objective of this study was to evaluate knowledge and behavior of medication use among guardians of left-behind children (LBC) and non-left-behind children (NLBC). Methods A cross-sectional study was conducted in Chengdu, the major city of southwestern China from May 2020 to August 2020. A logistic regression model was conducted to assess medication-related knowledge and behavior of guardians between the LBC group and NLBC group, adjusted for confounders. Stratified analysis was further performed. Results The overall mean scores for knowledge and for behavior were 20.22 (standard deviation = 4.472) and 15.77 (standard deviation = 3.604), respectively. No significant difference was found in medication-related knowledge and behavior scores between LBC and NLBC guardians (P > 0.05). A significant difference was only observed after adjusting for past medical history and history of present illness (HPI). Conclusion There was no significant difference in the awareness and behavior of medication use between guardians of LBC and NLBC in this study, having more contact with the doctor was an effective method of health education that could possibly improve their health literacy.

Abstract Hyperuricemia (HUA) refers to a physiological condition of high serum uric acid (SUA) level in the body, which may cause an increased risk of several chronic diseases. The kidney’s impaired uric acid (UA) metabolism is an important reason for HUA. In this study, we tested the hypothesis that circulating factors produced during exercise regulate the expression of ABCC4, ABCG2, URAT1, and GLUT9 in normal rat kidneys and normal rat kidney cells (NRK-52E) and their relationship with NF-κB and NRF-2. NRK-52E cells were separately cultured by serum from 10 healthy SD rats who did not exercise (CON) and 10 healthy SD rats who did aerobic treadmill exercise for 6 weeks. Cells cultured by serum from rats who did aerobic treadmill exercise for 6 weeks were separated by without NRF-2 inhibitor (EXE) and with NRF-2 inhibitor (EXE + ML). SUA level of rats was tested by using dry chemical assays, xanthine oxidase (XOD) activity in serum and liver were tested by using enzyme colorimetry assays, protein expression in kidney and NRK-52E cells were tested by using Western-blot, and UA levels in the upper or lower chamber were tested by colorimetry assays. Aerobic exercise reduced SUA levels in rats but did not significantly affect on liver xanthine oxidase. It also increased the expression of some UA transporters in the kidney and NRK-52E cells and increased the cells’ ability in UA excretion. When the NRF-2 was inhibited, the NF-κB and ABCG2 increased, and the expression of ABCC4, URAT1, and GLUT9 decreased. In conclusion, this study suggested that 6 weeks of aerobic treadmill exercise intervention may help to improve the excretion of UA in renal cells, suggesting that long-term aerobic exercise may be a means to prevent hyperuricemia.

On-orbit assembly has become a crucial aspect of space operations, where the manipulator frequently and directly interacts with objects in a complex assembly process. The traditional manipulator control has limitations in adapting to diverse assembly tasks and is vulnerable to vibration, leading to assembly failure. To address this issue, we propose a human-like variable admittance control method based on the variable damping characteristics of the human arm. By collecting the velocity and contact force of human arm operations in assembly, we analyze the damping change of human arm and establish the active compliance model based on S-type damping variation rule in assembly. Furthermore, 3 passive contact models are proposed between the end of the human arm and the environment: one-sided bevel contact, both sides bevel contact, and pin–hole contact. On the basis of these active and passive models, a typical space assembly task for a robot is designed, and a human-like variable admittance controller is established and simulated. Finally, we build a ground verification platform and complete different assembly tasks, thereby successfully verifying the safety, robustness, and adaptability of the human-like variable admittance control method.

In this study, we proposes a humanoid dual-arm explosive ordnance disposal (EOD) robot design. First, a seven-degree-of-freedom high-performance collaborative and flexible manipulator is developed, aiming at the transfer and dexterous operation of dangerous objects in EOD tasks. Furthermore, an immersive operated humanoid dual-arm dexterous explosive disposal robot (FC-EODR) is designed, which has a high passability to complex terrains such as low walls, slope roads, and stairs. It can remotely detect, manipulate, and remove explosives in dangerous environments through immersive velocity teleoperation. In addition, an autonomous tool-changing system is constructed, which enables the robot to flexibly switch between different tasks. The effectiveness of the FC-EODR is finally verified through a series of experiments, including the platform performance test, manipulator load test, teleoperated wire trimming, and screw-screwing experiments. This letter provides the technical foundation for robots to replace humans in EOD tasks and emergency situations.

In nonlinear optical systems, the optical superposition principle breaks down. The system’s response (including electric polarization, current density, etc) is not proportional to the stimulus it receives. Over the past half century, nonlinear optics has grown from an individual frequency doubling experiment into a broad academic field. The nonlinear optics has not only brought new physics and phenomena, but also has become an enabling technology for numerous areas that are vital to our lives, such as communications, health, advanced manufacturing, et al . This Roadmap surveys some of the recent emerging fields of the nonlinear optics, with a special attention to studies in China. Each section provides an overview of the current and future challenges within a part of the field, highlighting the most exciting opportunities for future research and developments.

Earth’s aurora is a luminescent phenomenon generated by the interaction between magnetospheric precipitating particles and the upper atmosphere; it plays an important role in magnetosphere–ionosphere (M-I) coupling. The transpolar arc (TPA) is a discrete auroral arc distributed in the noon-midnight direction poleward of the auroral oval and connects the dayside to the nightside sectors of the auroral oval. Studying the seasonal variation of TPA events can help us better understand the long-term variation of the interaction between the solar wind, the magnetosphere, and M-I coupling. However, a statistical study of the seasonal variation of TPA incidence has not previously been carried out. In this paper, we have identified 532 TPA events from the IMAGE database (2000–2005) and the Polar database (1996–2002), and calculated the incidence of TPA events for different months. We find a semiannual variation in TPA incidence. Clear peaks in the incidence of TPAs occur in March and September; a less pronounced peak appears in November. We also examine seasonal variation in the northward interplanetary magnetic field (IMF) over the same time period. The intensity and occurrence rate of the northward IMF exhibit patterns similar to that of the TPA incidence. Having studied IMF Bz before TPA onset, we find that strong and steady northward IMF conditions are favorable for TPA formation. We suggest that the semiannual variation observed in TPA incidence may be related to the Russell–McPherron (R-M) effect due to the projection effect of the IMF By under northward IMF conditions.

BackgroundEvidence from a variety of studies link mobile phone use with an increase in mental health problems, with the situation being particularly prevalent in China and exacerbated by the COVID-19 quarantine. ObjectiveThis study aims to reveal underlying connections between mobile phone use and mental disorders of adolescents, and to develop a theory to help parents and counseling psychologists better understand and intervene in future cases. MethodsA total of 37 teenagers having both mental health and mobile phone use problems, along with their parents, were included for individual interviews. These interviews were transcribed, coded, and analyzed using qualitative methods of grounded theory. ResultsThe grades-ranking-first mentality is one of the main factors causing problems such as defective family bonding and peer influences, pushing teenagers with mental disorders to seek comfort in the virtual world through their cellphones. ConclusionsThe idea proposed in this study is not only inspiring for psychological counseling and therapy on adolescents with mental problems but also beneficial for school educators and parents to better understand the adolescents. The findings of the study are also particularly noteworthy in the postpandemic age, where parents whose work locations and schedules are substantially affected due to any emergencies should try to build a relaxing and cozy atmosphere at home to avoid possible conflicts with adolescents.

Abstract Background Dysregulation of alternative splicing (AS) is a critical signature of cancer. However, the regulatory mechanisms of cancer-specific AS events, especially the impact of DNA methylation, are poorly understood. Methods By using The Cancer Genome Atlas (TCGA) SpliceSeq and TCGA data for ten solid tumor types, association analysis was performed to characterize the potential link between cancer-specific AS and DNA methylation. Functional and pathway enrichment analyses were performed, and the protein-protein interaction (PPI) network was constructed with the String website. The prognostic analysis was carried out with multivariate Cox regressions models. Results 15,818 AS events in 3955 annotated genes were identified across ten solid tumor types. The different DNA methylation patterns between tumor and normal tissues at the corresponding alternative spliced exon boundaries were shown, and 51.3% of CpG sites (CpGs) revealed hypomethylated in tumors. Notably, 607 CpGs were found to be highly correlated with 369 cancer-specific AS events after permutation tests. Among them, the hypomethylated CpGs account for 52.7%, and the number of down-regulated exons was 173. Furthermore, we found 38 AS events in 35 genes could serve as new molecular biomarkers to predict patient survival. Conclusions Our study described the relationship between DNA methylation and AS events across ten human solid tumor types and provided new insights into intragenic DNA methylation and exon usage during the AS process.

Objective: This study aims to evaluate the effect of psychological interventions on healthcare providers (HCP) with post-traumatic stress disorder (PTSD) due to their necessary exposure in life-threatening pandemic.Methods: We performed a systematic research on Medline, Embase, Cochrane Central, PsycInfo, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, ProQuest PTSD Pubs ProQuest Dissertations & Theses Global, and other gray databases by January 2021. Randomized controlled trials involving therapeutic interventions for HCP with PTSD were included. The primary outcome was PTSD symptom severity. Summary standardized mean differences (SMDs) and 95% confidence intervals were estimated using inverse variance meta-analysis with fixed effects. Risks of bias were assessed using Cochrane methods.Results: Among 773 citations, this review includes six studies, randomizing 810 participants. A meta-analysis of the effect of interventions compared to placebo showed a significant reduction of PTSD symptom severity: Cognitive Behavioral Therapy-Brief (CBT-B) (M = 27.80, 95% CI: 17.12, 38.48), Cognitive Behavioral Therapy-Long (CBT-L) (M = 26.50, 95% CI: 15.75, 37.25), and Mindfulness-Based Stretching and Deep Breathing Exercise (MBX) (M = 17.2, 95% CI: 6.57, 27.83). CBT-L and CBT-B also showed a significant effect on depression severity.Conclusions: The most effective and feasible treatment option for HCP with PTSD is still unclear, but CBT and MBX have displayed the most significant effects based on current limited evidence. Future research in this area—preferably large robust randomized controlled trials—is much needed.

Using space stations for a large number of observation, exploration, and research is a necessary way to fully develop space technology. It is a necessary means of space experiment to install the extravehicular experimental load by using the load plate. However, the extravehicular environment is full of danger, which poses a threat to the health and even safety of astronauts. Using robots to replace astronauts to complete this task can effectively reduce the threat to astronauts. Aiming at the problem that the configurations of existing space robots have difficulty in balancing the contradiction between complexity and dexterity, our previous work proposes a 12-DOF 3-arm robot and preliminarily explores the feasibility of its large-scale ability. This paper focus on the 8-DOF redundant dexterous manipulator composed of 2 of the robot arms. In view of the difficulties in solving the inverse kinematics of the redundant manipulator, the challenges of complex environmental lighting, and difficulties of matching multiple groups of holes and pins in the load plate assembly task, the research on the autonomous assembly of the load plate is carried out. The main work is as follows: (a) A variable D-H parameter inverse kinematics solution method is proposed, which lays a foundation for humanoid dexterous operation planning of the robot. (b) An autonomous operation method based on visual guidance and variable parameter admittance control is proposed. Finally, the safety and robustness of the robot in the autonomous assembly of the load plate with multipins and holes are successfully verified by experiments.

This paper proposes a novel chameleon-like astronaut robot that is designed to assist, or even substitute, a human astronauts in a space station to complete dangerous and prolonged work, such as maintenance of solar panels, and so on. The robot can move outside the space station freely via the hundreds of aluminum handrails, which are provided to help astronauts move. The robot weighs 30 kilograms, and consists of a torso, three identical 4-degree of freedom (DOF) arms, three end effectors, and three monocular vision system on each end effector. Via multi-arm associated motion, the robot can realize three kinds of motion modes: walking, rolling, and sliding. Numerous experiments have been conducted in a simulation environment and a ground verification platform. Experimental results reveal that this robot has excellent motion performance.