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Nitrogen capture is a crucial strategy for coping with the environmental crisis arising from continually industrial NO emissions, while it suffers from the generally inefficient aquatic absorbent. This work developed a novel absorbent with favorable gas affinity via using sterically hindered imidazole to regulate the gas–liquid interface of typical K2S2O8 solution, initially achieving an efficiently catalytic absorption of poorly soluble NO. The best catalytic absorption efficiencies increased from 17.83% to 91.90% as compared to traditional one. Moreover, an established absorption kinetic model indicated that both capacity and rate of NO dissolution were increased. The imidazole molecules spontaneously migrated to gas–liquid interface of solution and imparted an additional dissolution impetus to NO. This catalytic absorption method overcoming the conventional NO dissolution limitation in water not only improves commercial NO capture, but also provides a new design of aquatic absorbent for heterogeneous reactions requiring transporting poorly soluble gases in aqueous solvents. [ABSTRACT FROM AUTHOR]

Rapid detection and identification of opioids are of great significance and an urgent need in drug regulation and forensic science. Fentanyl is an extremely potent synthetic drug of abuse that unfortunately cannot be accurately detected. Therefore, techniques combining fast, highly sensitive and portable for fentanyl detection need to be developed. Surface‐enhanced Raman spectroscopy (SERS) has emerged as a promising detection technique owing to its high sensitivity and selectivity. Here, we reported a nonmetal SERS substrate used for trace fentanyl detection. The lowest detectable concentration was 10−7 M, and the MoO2 substrate exhibited excellent thermal and chemical stability, which could even ensure high‐temperature heating, laser irradiation, and corrosion of strong acid or alkali. [ABSTRACT FROM AUTHOR]

It is significant to develop catalysts with high catalytic activity and durability to improve the electrochemical performances of lithium‐oxygen batteries (LOBs). While electronic metal‐support interaction (EMSI) between metal atoms and support has shown great potential in catalytic field. Hence, to effectively improve the electrochemical performance of LOBs, atomically dispersed Fe modified RuO2 nanoparticles are designed to be loaded on hierarchical porous carbon shells (FeSA‐RuO2/HPCS) based on EMSI criterion. It is revealed that the Ru‐O‐Fe1 structure is formed between the atomically dispersed Fe atoms and the surrounding Ru sites through electron interaction, and this structure could act as the ultra‐high activity driving force center of oxygen reduction/evolution reaction (ORR/OER). Specifically, the Ru‐O‐Fe1 structure enhances the reaction kinetics of ORR to a certain extent, and optimizes the morphology of discharge products by reducing the adsorption energy of catalyst for O2 and LiO2; while during the OER process, the Ru‐O‐Fe1 structure not only greatly enhances the reaction kinetics of OER, but also catalyzes the efficient decomposition of the discharge products Li2O2 by the favorable electron transfer between the active sites and the discharge products. Hence, LOBs based on FeSA‐RuO2/HPCS cathodes show an ultra‐low over‐potential, high discharge capacity and superior durability. [ABSTRACT FROM AUTHOR]

Nanocatalytic therapy, involving the nanozyme‐triggered production of reactive oxygen species (ROS) in the tumor microenvironment (TME), has demonstrated potential in tumor therapy, but nanozymes still face challenges of activity and specificity that compromise the therapeutic efficacy. Herein, we report a strategy based on a single‐atom nanozyme to initiate cascade enzymatic reactions in the TME for tumor‐specific treatment. The cobalt‐single‐atom nanozyme, with Co−N coordination on N‐doped porous carbon (Co‐SAs@NC), displays catalase‐like activity that decomposes cellular endogenous H2O2 to produce O2, and subsequent oxidase‐like activity that converts O2 into cytotoxic superoxide radicals to efficiently kill tumor cells. By incorporation with doxorubicin, the therapy achieves a significantly enhanced antitumor effect in vivo. Our findings show that cascade TME‐specific catalytic therapy combined with chemotherapy is a promising strategy for efficient tumor therapy. [ABSTRACT FROM AUTHOR]

Rechargeable Li‐CO2 batteries have received a lot of attention due to their high energy density and ability to fix the greenhouse gas CO2. However, the lagged kinetics of CO2 reduction reaction (CRR) and CO2 evolution reaction (CER) has been restricting the development and application of Li‐CO2 batteries. Herein, ultrafine Ru/RuO2 nanoparticles anchored on hierarchical porous carbon shell (Ru/RuO2‐HPC) is designed and applied as an efficient cathode catalyst for Li‐CO2 batteries. The anchored Ru/RuO2 nanoparticles act as catalytic site not only accelerate CRR and CER kinetics but also tailor the reaction process of Li‐CO2 batteries, making discharge products are more susceptible to form sheet‐like by a surface‐adsorption pathway, which is easier to be decomposed in charge process. As a result, Li‐CO2 battery based on Ru/RuO2‐HPC cathode displays enhanced electrochemical performances, including high capacity, excellent round‐trip efficiency, and outstanding cycling stability. [ABSTRACT FROM AUTHOR]

Li‐CO2 battery has attracted extensive attention and research due to its super high theoretical energy density and its ability to fix greenhouse gas CO2. However, the slow reaction kinetics during discharge/charge seriously limits its development. Hence, a simple cation exchange strategy is developed to introduce Ru atoms onto a Co3O4 nanosheet array grown on carbon cloth (SA Ru‐Co3O4/CC) to prepare a single atom site catalyst (SASC) and successfully used in Li‐CO2 battery. Li‐CO2 batteries based on SA Ru‐Co3O4/CC cathode exhibit enhanced electrochemical performances including low overpotential, ultra high capacity, and long cycle life. Density functional theory calculations reveal that single atom Ru as the driving force center can significantly enhance the intrinsic affinity for key intermediates, thus enhancing the reaction kinetics of CO2 reduction reaction in Li‐CO2 batteries, and ultimately optimizing the growth pathway of discharge products. In addition, the Bader charge analysis indicates that Ru atoms as electron‐deficient centers can enhance the catalytic activity of SA Ru‐Co3O4/CC cathode for the CO2 evolution reaction. It is believed that this work has important implications for the development of new SASCs and the design of efficient catalyst for Li‐CO2 batteries. [ABSTRACT FROM AUTHOR]

Objective: To explore the main causes of hypertrophied ligamentum flavum (HLF) and the possibility of using bipedal standing mouse model to simulate the pathological changes in human HLF. Methods: Thirty‐two 8‐week‐old C57BL/6 male mice were randomly assigned to the experimental group (n = 16) and control group (n = 16). In the experimental group, mice were induced to adopt a bipedal standing posture by their hydrophobia. The experimental mice were maintained bipedal standing for 8 h a day with an interval of 2 h to consume food and water. The control mice were placed in a similar environment without bipedal standing. Eight 18‐month‐old C57BL/6 male mice were compared to evaluate the LF degeneration due to aging factor. Three‐dimensional (3D) reconstruction and finite element models were carried out to analyze the stress and strain distribution of the mouse LF in sprawling and bipedal standing postures. Hematoxylin and Eosin (HE), Verhoeff‐Van Gieson (VVG), and immunohistochemistry (IHC) staining were used to evaluate the LF degeneration of mice and humans. RT‐qPCR and immunofluorescence analysis were used to evaluate the expressions of fibrosis‐related factors and inflammatory cytokines of COL1A1, COL3A1, α‐SMA, MMP2, IL‐1β, and COX‐2. Results: The von Mises stress (8.85 × 10−2 MPa) and maximum principal strain (6.64 × 10−1) in LF were increased 4944 and 7703 times, respectively, in bipedal standing mice. HE staining showed that the mouse LF area was greater in the bipedal standing 10‐week‐old group ([10.01 ± 2.93] × 104 μm2) than that in the control group ([3.76 ± 1.87] × 104 μm2) and 18‐month‐old aged group ([6.09 ± 2.70] × 104 μm2). VVG staining showed that the HLF of mice (3.23 ± 0.58) and humans (2.23 ± 0.31) had a similar loss of elastic fibers and an increase in collagen fibers. The cell density was higher during the process of HLF in mice (39.63 ± 4.81) and humans (23.25 ± 2.05). IHC staining showed that the number of α‐SMA positive cells were significantly increased in HLF of mice (1.63 ± 0.74) and humans (3.50 ± 1.85). The expressions of inflammatory cytokines and fibrosis‐related factors of COL1A1, COL3A1, α‐SMA, MMP2, IL‐1β, and COX‐2 were consistently higher in bipedal standing group than the control group. Conclusion: Our study suggests that 3D finite element models can help analyze the abnormal stress and strain distributions of LF in modeling mice. Mechanical stress is the main cause of hypertrophied ligamentum flavum compared to aging. The bipedal standing mice model can reflect the pathological characteristics of human HLF. The bipedal standing mice model can provide a standardized condition to elucidate the molecular mechanisms of mechanical stress‐induced HLF in vivo. [ABSTRACT FROM AUTHOR]

Promotion of spermatogonial stem cell (SSC) differentiation into functional sperms under in vitro conditions is a great challenge for reproductive physiologists. In this study, we observed that melatonin (10−7 m) supplementation significantly enhanced the cultured SSCs differentiation into haploid germ cells. This was confirmed by the expression of sperm special protein, acrosin. The rate of SSCs differentiation into sperm with melatonin supplementation was 11.85 ± 0.93% which was twofold higher than that in the control. The level of testosterone, the transcriptions of luteinizing hormone receptor (LHR), and the steroidogenic acute regulatory protein (StAR) were upregulated with melatonin treatment. At the early stage of SSCs culture, melatonin suppressed the level of cAMP, while at the later stage, it promoted cAMP production. The similar pattern was observed in testosterone content. Expressions for marker genes of meiosis anaphase, Dnmt3a, and Bcl-2 were upregulated by melatonin. In contrast, Bax expression was downregulated. Importantly, the in vitro-generated sperms were functional and they were capable to fertilize oocytes. These fertilized oocytes have successfully developed to the blastula stage. [ABSTRACT FROM AUTHOR]

SUMMARY To determine whether the actual pretension of membrane structure tallies with the design pretension and whether the membrane structure is relaxed after employing, we must monitor the actual pretension of the building membrane structure accurately and then adopt some measures to ensure the engineering quality and reduce the engineering accidents. The pretension monitoring of the building membrane structure belongs to the structural nondestructive health monitoring field. The authors of this paper developed a new method-ejection method for monitoring the pretension of building membrane structure accurately and nondestructively. The basic idea of this method was represented, and the theoretical model of this method was established by studying the large amplitude nonlinear vibration problem of the orthotropic membrane, and then the theoretical measurement formula was derived by the energy conservation principle. Meanwhile, the finite element numerical analysis was carried out for the theoretical model, and the ejection experiment for the three kinds of conventional membrane material (Mehler FR-900 (Mehler Texnologies, Hückelhoven, Germany), Ferrari 502S (Ferrari, Cape Town, South Africa), and Yilong 750 (Yilong, Guangdong, China)) was carried out according to the theoretical idea. The numerical analysis and experimental results proved that the ejection method is feasible and verified that the theoretical derivation is correct. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

To investigate the driving stability of tank trucks, an equivalent trammel pendulum was utilized to approximately demonstrate the dynamic characteristics of liquid sloshing in a partially filled tank. The oscillation movement of the trammel pendulum in the tank was described under the tank-fixed coordinate system and its motion equation under the noninertia coordinate system was derived using a Lagrangian function. The motion of the pendulum that expresses the fluid cargo dynamic behavior and that of the solid truck was coupled with each other by the tank. Therefore, a tank truck dynamic model was established using Newton's first law and the angular momentum. A typical tank truck was selected and used to study its driving stability under steering angle step test. The study on tankers driving stability is of great importance for evaluating tankers driving safety, investing the main impact factor aspecting tankers driving stability, and developing active/passive roll control systems for them. [ABSTRACT FROM AUTHOR]

We propose a class of new double projection algorithms for solving variational inequality problem, which can be viewed as a framework of the method of Solodov and Svaiter by adopting a class of new hyperplanes. By the separation property of hyperplane, our method is proved to be globally convergent under very mild assumptions. In addition, we propose a modified version of our algorithmthat finds a solution of variational inequality which is also a fixed point of a given nonexpansivemapping. If, in addition, a certain local error bound holds, we analyze the convergence rate of the iterative sequence. Numerical experiments prove that our algorithms are efficient. [ABSTRACT FROM AUTHOR]

Background Neural tube defects (NTDs) are common and serious birth defects all over the world. Prenatal screening for NTDs using maternal serum alpha-fetoprotein (MSAFP) during the second trimester of pregnancy has been widely used, but its effectiveness remains unclear. Methods We evaluated the studies published in the English and Chinese on MSAFP screening for NTDs. The homogeneity of the studies was evaluated by the forest graph. Meta-analysis was applied to calculate the combined effect values and their 95% confidence intervals. Results As many as 22 articles were selected according to the criteria and were included in the meta-analysis, for a total of 684 140 pregnant women screened during the second trimester. All the studies selected were homogenous according to the forest graph (χ2 = 25.17, P > 0.10). The combined relative risk estimate was 0.25 and its 95% confidence interval was 0.21 to 0.29. The combined protective rate was 75%. The sensitivity and specificity of MSAFP screening were 75.1 and 97.7%, respectively. Conclusion Use of MSAFP during the second trimester in pregnant women is an effective measure for the screening of NTDs. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Methods Results Conclusion Lumbar disc herniation (LDH) is a common degenerative spinal disease in clinical practice. This study aims to investigate the impact of Modic changes (MCs) on postoperative recovery and disease recurrence following percutaneous endoscopic lumbar disc discectomy (PELD), providing important insights for improving the management of chronic low back pain. This study investigates the 1‐year progression rate of MCs after PELD and their impact on surgical outcomes and recurrence.This retrospective cohort study analyzed data from 419 patients with single‐segment lumbar disc herniation who underwent PELD between January 2019 and December 2022. Lumbar MRI assessed preoperative and postoperative MCs. Pain levels and surgical outcomes were evaluated using the visual analog scale, Oswestry Disability Index, and Macnab criteria. Univariate analysis explored the relationship between postoperative MCs and pain, while subgroups investigated the associations between postoperative efficacy, recurrence, and MCs type and area.One‐year follow‐up revealed that the probability of MCs postsurgery was 24.8%. Patients with postoperative MCs had significantly lower pain scores compared with the control group (p < 0.05). Univariate analysis indicated that the type and area of postoperative MCs were risk factors for poor outcomes in PELD patients (p < 0.05). During the 1‐year follow‐up, recurrence rates in the no‐MCs and MCs groups were 3.8% and 9.6%, respectively (p < 0.05). Univariate analysis concluded that the area of postoperative MCs was a risk factor for PELD recurrence.The postoperative MCs, as a risk factor, may have a detrimental effect on the surgical efficacy and short‐term recurrence of LDH following PELD based on a large sample. Furthermore, the harmful effect is affected by the area and type of the postoperative MCs. [ABSTRACT FROM AUTHOR]