Explore the vast range of titles available.

Polyolefins are used widely due to their benefits such as being lightweight, chemical inertness, low cost, tunable properties, and easy processability. However, their nonpolar nature significantly limits their high-end applications. The non-bridged half-titanocenes exhibit remarkable catalytic activities with good comonomer incorporations in the olefin polymerization. The synthesis of functional polyolefins has attracted more and more attention recently. The non-bridged half-titanocenes have been used in the preparation of functional polyolefins, in particular the functional olefin copolymers. Herein, the recent advancements in the synthesis of functional polyolefins by non-bridged half-titanocenes were reviewed. The functional polyolefins have been synthesized by direct copolymerization of olefin with functional comonomers using half-titanocenes as precatalysts. In addition, polyolefins containing reactive groups could be synthesized by the olefin (co)polymerization using half-titanocenes as precatalysts. The functional polyolefins were synthesized successfully by the post-functionalization of polyolefin containing reactive groups.

Photocatalytic oxidative coupling of methane with oxygen is promising to obtain valuable muti-carbon products, yet suffering low reactivity. Here, we apply cerium modifications on zinc oxide-supported gold catalysts based on the electronic asymmetry design of lattice oxygen to improve the coupling activity. The methane conversion rate exceeds 16000 μmol g −1  h −1 with muti-carbon selectivity of 94.9% and catalytic durability of 3 days, and it can increase to 34000 μmol g −1  h −1 under more thermal assistance, with a turnover frequency of 507 h −1 for ethane and an apparent quantum efficiency of 33.7% at 350 nm. According to systematic characterizations and theoretical analysis, cerium dopants not only can boost the formation of reactive oxygen species but also intervene in the vivacity of lattice oxygen by manipulating metal-oxygen bond strength, thereby leading to favorable methyl desorption to form ethane and quick water release. This work provides insight into the rational design of efficient photocatalysts for aerobic methane-to-ethane conversion. Photocatalytic oxidative coupling of methane is a promising approach to create muti-carbon products. Here, the authors use Ce dopants to construct electronically asymmetric lattice oxygen sites in ZnO to enhance methyl migration and promote C-C coupling.

As a key professional competence of teachers, empathy involves whether teachers can stand in the student's position to pay attention, understand their behavior, and make reasonable judgment and explanation of it. Researchers have discovered that 360° virtual reality (360° VR), a relatively recent form of media, can be particularly powerful in encouraging individuals to adopt different perspectives and understand the world from others' viewpoints. But few studies have explored the use of 360° VR in teachers' empathy fostering and the influence of 360° VR on empathy are underexplored. Hence, this study aims to investigate the potential impact of 360° VR on the cultivation of pre-service teachers' empathy, particularly in comparison to traditional media forms, and explored the impact of user experiences such as immersion, engagement, and discomfort in 360° VR. We use an experimental design to compare the impact of different media (i.e., 360° VR, 2D video, and text-image) on pre-service teachers' empathy. Our main findings indicate that: (1) 360° VR group showed significantly higher level of empathy than 2D video and text-image groups; (2) immersion positively correlated with engagement and empathy, while engagement negatively correlated with discomfort. The study suggests the viability of utilizing 360° VR for training pre-service teachers' empathy, but it requires an integration of effective learning activities and scaffolding design.

In this invited paper, a highly sensitive methane (CH4) trace gas sensor based on quartz-enhanced photoacoustic spectroscopy (QEPAS) technique using a high-power diode laser and a miniaturized 3D-printed acoustic detection unit (ADU) is demonstrated for the first time. A high-power diode laser emitting at 6057.10 cm−1 (1650.96 nm), with the optical power up to 38 mW, was selected as the excitation source to provide a strong excitation. A 3D-printed ADU, including the optical and photoacoustic detection elements, had a dimension of 42 mm, 27 mm, and 8 mm in length, width, and height, respectively. The total weight of this 3D-printed ADU, including all elements, was 6 g. A quartz tuning fork (QTF) with a resonant frequency and Q factor of 32.749 kHz and 10,598, respectively, was used as an acoustic transducer. The performance of the high-power diode laser-based CH4–QEPAS sensor, with 3D-printed ADU, was investigated in detail. The optimum laser wavelength modulation depth was found to be 0.302 cm−1. The concentration response of this CH4–QEPAS sensor was researched when the CH4 gas sample, with different concentration samples, was adopted. The obtained results showed that this CH4–QEPAS sensor had an outstanding linear concentration response. The minimum detection limit (MDL) was found to be 14.93 ppm. The normalized noise equivalent absorption (NNEA) coefficient was obtained as 2.20 × 10−7 cm−1W/Hz−1/2. A highly sensitive CH4–QEPAS sensor, with a small volume and light weight of ADU, is advantageous for the real applications. It can be portable and carried on some platforms, such as an unmanned aerial vehicle (UAV) and a balloon.

Skin-integrated haptic interfaces that can relay a wealth of information from the machine to the human are of great interest. However, existing haptic devices are not yet able to produce haptic cues that are compatible with the skin. In this work, we present the stretchable soft actuators for haptic feedback, which can match the perception range, spatial resolution, and stretchability of the skin. Pressure-amplification structures are fabricated using a scalable self-assembly process to ensure an output pressure beyond the skin perception threshold. Due to the minimized device size, the actuator array can be fabricated with a sufficiently high spatial resolution, which makes the haptic device applicable for skin locations with the highest spatial acuity. A haptic feedback system is demonstrated by employing the developed soft actuators and highly sensitive pressure sensors. Two proof-of-concept applications are developed to illustrate the capability of transferring information related to surface textures and object shapes acquired at the robot side to the user side.

In order to enhance the management and application of fault knowledge within intelligent production lines, thereby increasing the efficiency of fault diagnosis and ensuring the stable and reliable operation of these systems, we propose a fault diagnosis methodology that leverages knowledge graphs. First, we designed an ontology model for fault knowledge by integrating textual features from various components of the production line with expert insights. Second, we employed the ALBERT–BiLSTM–Attention–CRF model to achieve named entity and relationship recognition for faults in intelligent production lines. The introduction of the ALBERT model resulted in a 7.3% improvement in the F1 score compared to the BiLSTM–CRF model. Additionally, incorporating the attention mechanism in relationship extraction led to a 7.37% increase in the F1 score. Finally, we utilized the Neo4j graph database to facilitate the storage and visualization of fault knowledge, validating the effectiveness of our proposed method through a case study on fault diagnosis in CNC machining centers. The research findings indicate that this method excels in recognizing textual entities and relationships related to faults in intelligent production lines, effectively leveraging prior knowledge of faults across various components and elucidating their causes. This approach provides maintenance personnel with an intuitive tool for fault diagnosis and decision support, thereby enhancing diagnostic accuracy and efficiency.

Lactate-driven metabolic reprogramming and histone lactylation play pivotal roles in bladder cancer (BLCA) progression, yet their underlying mechanisms and regulatory genes remain poorly understood. Using transcriptomic data from The Cancer Genome Atlas (TCGA), we identified lactylation-associated genes and constructed a prognostic signature. Comprehensive bioinformatics analyses were conducted to assess immune infiltration, tumor microenvironment characteristics, and the lactylation landscape at the single-cell level. Furthermore, we performed experiments to evaluate the biological functions of key lactylation-related genes in BLCA cells. Six lactylation-related hub genes were identified, among which FASN and RUNX2 were significantly upregulated in BLCA and associated with poor prognosis. Single-cell analyses revealed elevated lactylation signatures in tumor epithelial and immune cells. Knockdown of FASN or RUNX2 in BLCA cell lines significantly suppressed cell proliferation, induced apoptosis, and reduced intracellular lactate levels. Correspondingly, global protein lactylation was diminished, with dominant modification signals observed around 40 kDa, indicating a potential set of non-histone proteins as key functional targets. Our study highlights a metabolic-enzymatic axis wherein FASN and RUNX2 regulate lactate-driven protein lactylation in BLCA. These findings provide new insights into the non-histone functions of lactylation and suggest potential therapeutic targets at the intersection of metabolism and tumor immunity.

In recent years, transgenic technology has developed rapidly, but the risk of the environmental release of transgenic organisms is still a key issue. Research on the impact on biodiversity is an effective way to objectively evaluate the risk. By taking transgenic maize HGK60 with insect-resistant gene Cry1Ah and common maize Zheng 58 as control, a 2-year experiment of arthropod community biodiversity in fields of them were studied using three methods.in 2019 and 2020. The results showed that a total of 124 species and 38537 individuals were observed from the experiment, belonging to 11 orders and 40 families. There was no significant difference in the individual number and species number of herbivorous, predatory and parasitic groups in the two kinds of maize in two years. Only the individual number of HGK60 was significantly higher than that of common maize Zheng 58 at heading stage in 2019. And the percentages of individual number and species number in different groups were basically the same in the two kinds of maize at each stage in two years. Analyses of Richness index, Shannon-Wiener diversity index, Dominance index and Evenness index showed no significant difference between the two kinds of maize in two years. The similarity coefficient of the arthropod community suggested that the arthropod community composition of HGK60 was similar to that of common maize Zheng 58. Furthermore, HGK60 had no significant effect on the relative stability of the arthropod community. These results indicated that despite the presence of a relatively minor difference in arthropod community between the two kinds of maize, the planting of HGK60 had little effect on arthropod community biodiversity. The results provided some data and support for the further studies of environmental risk of transgenic crops.

Fiber optic gyroscope (FOG)-based north finding is extensively applied in navigation, positioning, and various fields. In dynamic north finding, an accelerated turntable speed shortens the time required for north finding, resulting in a rapid north-finding response. However, with an increase in turntable speed, the turntable’s jitter contributes to signal contamination in the FOG, leading to a deterioration in north-finding accuracy. This paper introduces a divide-and-conquer algorithm, the segmented cross-correlation algorithm, designed to mitigate the impact of turntable speed jitter. A model for north-finding error is established and analyzed, incorporating FOG’s self-noise and the turntable’s speed jitter. To validate the feasibility of our method, we implemented the algorithm on a FOG. The simulation and experimental results exhibited a strong concordance, affirming the validity of our proposed north-finding error model. The experimental findings indicate that, at a turntable speed of 180°/s, the north-finding bias error within a 360 s duration is 0.052°, representing a 64% improvement over the traditional algorithm. These results indicate the effectiveness of the proposed algorithm in mitigating the impact of unstable turntable speeds, offering a solution for north finding with both prompt response and enhanced accuracy.

Adipose tissue macrophages can promote beige adipose thermogenesis by altering local sympathetic activity. Here, we perform sympathectomy in mice and further eradicate subcutaneous adipose macrophages and discover that these macrophages have a direct beige-promoting function that is independent of sympathetic system. We further identify adipocyte Ets1 as a vital mediator in this process. The anti-inflammatory M2 macrophages suppress Ets1 expression in adipocytes, transcriptionally activate mitochondrial biogenesis, as well as suppress mitochondrial clearance, thereby increasing the mitochondrial numbers and promoting the beiging process. Male adipocyte Ets1 knock-in mice are completely cold intolerant, whereas male mice lacking Ets1 in adipocytes show enhanced energy expenditure and are resistant to metabolic disorders caused by high-fat-diet. Our findings elucidate a direct communication between M2 macrophages and adipocytes, and uncover a function for Ets1 in responding to macrophages and negatively governing mitochondrial content and beige adipocyte formation. Adipose beiging is a positive biological change, which is often thought to be primarily sympathetically induced. Here, the authors show that M2 macrophages can independently promote beige adipogenesis, further revealing the adipocyte transcription factor Ets1 as a negative regulator of this process.