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This review focuses on recent advances in the synthesis of urea via electrocatalytic CN coupling of CO2and nitrogenous molecules.

Two-dimensional (2D) materials, such as graphene, are sensitive to electrostatic and strain effects because their band structure significantly depends on the carrier density and carbon bond lengths and angles. Leveraging this principle, graphene-based transistors offer potential advantages for designing next-generation electronic devices through electrostatic and strain tunability. However, existing graphene-based transistors rarely exhibit variations in transport properties induced by strain. In this study, we fabricated a transistor composed of graphene and PbZr0.52Ti0.48O3(PZT), where graphene served as the conductive channel and PZT as the field gate layer. Experimental observations revealed that applying voltage to PZT resulted in a hysteresis characteristic in the graphene transport curve, and the current curve Ids–Vgexhibited distinct dual loops, one resembling a rectangle and the other resembling a butterfly curve. These effects arise from the combined influences of the ferroelectricity and piezoelectricity of PZT. Consequently, the conductivity of graphene can be tuned through carrier accumulation and depletion and continuous in-plane stress. This discovery enriches the design strategy for 2D-based electronic devices with multiple external field modulations.

β-amyloid (Aβ) deposits are the leading cause of Alzheimer's disease. Many studies have confirmed that transthyretin (TTR) inhibits the cytotoxicity of Aβ oligomers (AβOs) with various species (oligomers and protofibrils, but not monomers) through their interactions. Here, we investigated the mechanisms of interactions between the TTR tetramer and various Aβ species, including two monomers with different morphologies and four oligomers with different molecular weights, by employing molecular dynamics simulations. From these results, we propose a clear interaction scenario: upon AβO binding, the dimer−dimer distance of TTR increases and the binding energy decreases, indicating an unfavorable effect on the TTR stability. Moreover, the larger the molecular weight (MW) of AβO, the greater the effect of interaction between the TTR tetramer and Aβ oligomer, and consequently the worse the TTR stability. In turn, Aβ–Aβ intermolecular distances in AβO grow and the hydrophobic solvent-accessible surface area (SASA) increases, whereas the number of intermolecular hydrogen bonds decreases, indicating AβO disaggregation induced by the TTR binding. Moreover, a trend is observed for the disaggregation to increase as the MW of the AβO species increases. Finally, we reveal that conformations rich in helical sections rather than the semi-extended conformation are favored upon binding with TTR. Overall, this study provides a comprehensive molecular-level insight to better understand the mechanism and principles of interaction between the TTR tetramer and AβOs.

Photocatalytic technology harnesses solar energy to facilitate chemical transformations, presenting significant potential in energy generation and environmental remediation. However, the conventional O2evolution process is hindered by high reaction barriers and inefficiencies, which limit its widespread application. Therefore, exploring novel photocatalytic coupling strategies to replace water oxidation has become a key route to enhance the efficiency of H2production. In this review, organic pollutants removal and the valorization of organics as substitutes for water oxidation coupling strategies for photocatalytic H2production are comprehensively summarized. These strategies not only circumvent the high reaction barriers associated with O2evolution to enhance the H2production but also aid in the removing of organic pollutants or synthesis of value-added chemicals. We also present future research directions and underscore the significance of advanced catalyst design, in-depth analysis of reaction mechanisms, and systematic optimization strategies in realizing an efficient and sustainable photocatalytic process. This guidance is anticipated to provide theoretical and practical new insights for the future development of photocatalytic coupling reactions, fostering further explorations in the realm of renewable energy and environmental governance.

Background: Although phytoplankton are important primary producers in food webs, they are relatively less studied in large rivers compared to other types of systems. To fill this research gap, we studied phytoplankton taxonomic and functional composition and their relationships with water quality, habitat, climate, and land use across 30 river sections in the middle and lower reaches of the Yangtze River during 2017–2018. Results: Major observed phytoplankton groups were cyanobacteria, bacillariophyta, and chlorophyta. Phytoplankton total abundance, total biomass, and species richness significantly decreased in the dry season compared to the wet season, with the species and functional composition differing significantly between seasons. Phytoplankton species differences between seasons were mainly contributed by Oscillatoriasp., Pseudanabaenasp., and Melosira granulata. The dfferences in phytoplankton functional groups between seasons were mainly contributed by P (including Closteriumsp., Melosirasp.), Lo (including Merismopediasp., Peridiniumsp., Ceratiumsp., and Gymnodiniumsp.), and J (including Pediastrumsp., Tetraedronsp., Crucigeniasp., Scenedesmussp., and Coelastrumsp.). The variance partitioning showed that water quality (NO3-N, total suspended solids, turbidity) and habitat (water flow, river bank and river channel conditions) were critical factors in shaping phytoplankton patterns, followed by climate and land use. Conclusions: Results indicated that there was significant seasonal variation of phytoplankton in the Yangtze River, with water quality and habitat primarily driving phytoplankton patterns. Our study contributes to the understanding of natural and anthropogenic factors that drive seasonal successional processes of phytoplankton in the Yangtze River. These findings have important implications for environmental management as well as towards the ecological restoration of large rivers.

To enhance the precision and reliability of road crack detection, this study introduces an innovative neural network architecture. Strategies were implemented to effectively address the issue of overfitting resulting from the intricacy of the proposed SegCrackNet. Dropout layers, multi-level output fusion, and T-bridge block structures are employed in the network. This optimization allows for a more comprehensive exploitation of contextual information, demonstrating its instrumental role in the efficient detection of subtle variations. Experimental findings clearly demonstrate substantial improvements when compared to other network models. On the Crack500, Crack200, and pavement images datasets, remarkable enhancements in the average Intersection over Union (IoU) scores were observed, with increases of 4.3%, 9.4%, and 3.7%, respectively.

In this article, a collaborative design method for gyrotron magnetron injection gun (MIG) and solenoid is proposed for the first time. On this basis, the shape of the electrodes and solenoid sizes is optimized by the means of global optimization techniques. Simplified theory and numerical methods of MIG have been developed, and the results agree well with the PIC simulation. By using the new method, the calculation time is reduced and the numerical stability has been greatly improved compared with that directly solving the Lorentz equation. As an example, a helical electron beam with a velocity pitch ratio of 1.20 and a transverse velocity spread of 1.65% is obtained for G-band gyro-TWT.

Two-dimensional (2D) transition metal sulfides (TMDs) are emerging and highly well received 2D materials, which are considered as an ideal 2D platform for studying various electronic properties and potential applications due to their chemical diversity. Converting 2D TMDs into one-dimensional (1D) TMDs nanotubes can not only retain some advantages of 2D nanosheets but also providing a unique direction to explore the novel properties of TMDs materials in the 1D limit. However, the controllable preparation of high-quality nanotubes remains a major challenge. It is very necessary to review the advanced development of one-dimensional transition metal dichalcogenide nanotubes from preparation to application. Here, we first summarize a series of bottom-up synthesis methods of 1D TMDs, such as template growth and metal catalyzed method. Then, top-down synthesis methods are summarized, which included self-curing and stacking of TMDs nanosheets. In addition, we discuss some key applications that utilize the properties of 1D-TMDs nanotubes in the areas of catalyst preparation, energy storage, and electronic devices. Last but not least, we prospect the preparation methods of high-quality 1D-TMDs nanotubes, which will lay a foundation for the synthesis of high-performance optoelectronic devices, catalysts, and energy storage components

To avoid the epitaxy dilemma in various thin films, such as complex oxide, silicon, organic, metal/alloy, etc., their stacking at an atomic level and secondary growth are highly desired to maximize the functionality of a promising electronic device. The ceramic nature of complex oxides and the demand for accurate and long-range-ordered stoichiometry face severe challenges. Here, the transport and magnetic properties of the La0.7Ca0.3MnO3(LCMO) secondary growth on single-crystal freestanding SrTiO3(STO) membranes are demonstrated. It has been experimentally found that on an only 10 nm thick STO membrane, the LCMO can offer a bulk-like Curie temperature (TC) of 253 K and negative magnetoresistance of −64%, with a weak dependence on the thickness. The resurrected conductivity and ferromagnetism in LCMO confirm the advantages of secondary growth, which benefits from the excellent flexibility and transferability. Additionally, this study explores the integration strategy of complex oxides with other functional materials.

ABSTRACTAlternative splicing is a process causing mRNA translation to produce different proteins, and it is crucial for the development of tumours. In this study, we constructed a prognostic model related to alternative splicing events in hepatocarcinoma using bioinformatics analysis, including the alternative splicing of CSAD, AFMID, ZDHHC16, and IRF3. The model is an independent prognostic factor and can accurately predict a patient’s prognosis. IRF3 is a transcription factor related to the immune response. Its alternative splicing can affect the expression of various genes related to prognosis and plays an essential role in the tumour microenvironment. We also verified the expression of IRF3 exon skipping isoform in hepatocarcinoma at the mRNA level. In conclusion, we discovered that the alternative splicing of IRF3 is essential for the development of hepatocarcinoma. This study provides new insight into the development of treatments for hepatocarcinoma.

Background: The application of index of biotic integrity (IBI) to evaluate river health can be an essential method for river ecosystem management. However, these types of methods were developed in small, low-order streams, and are therefore, infrequently applied to large rivers. To that end, phytoplankton communities and environmental variables were monitored in 30 sampling segments of the middle and lower reaches of the Yangtze River, China during the wet (July–August) and dry (November–December) seasons in 2017–2018. We developed a phytoplankton-based index of biotic integrity (P-IBI) and used the index to assess the ecological health of the Yangtze River. Relationships among P-IBI, its component metrics, and environmental factors were analyzed across different seasons. Results: Results obtained from the P-IBI indicated that the phytoplankton-based ecological health of the Yangtze River was rated as “good” during both seasons, with an overall better condition in the dry season. During the wet season, there were scattered river segments with P-IBI ratings of “fair” or below. Water quality and land use appeared to shape the patterns of P-IBI. In the wet season, P-IBI negatively correlated with total phosphorus, nitrate, total suspended solids, turbidity, conductivity, and dissolved oxygen. In the dry season, P-IBI positively correlated with total nitrogen, ammonium, and nitrite, and negatively correlated with water temperature. Conclusions: The ecological health of the Yangtze River as reflected by the P-IBI exhibited spatial and temporal variability, with the effect of water quality being greater than that of local land use. This study indicated the importance of considering seasonal effects in detecting large river ecological health. These findings enhanced our understanding of the ecological health and characterized potential benchmarks for management of the Yangtze River. These findings also may be applicable to other large rivers elsewhere.