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Straw strip burial in saline soil is an effective method for tideland reclamation in China, but optimal forms of straw strips for regulating soil water and salinity remain unclear. An indoor soil column test investigated the water and salt distribution in soil treated with four different straw forms under freshwater irrigation. The treatments included no straw layer (CK), straw stalks arranged longitudinally (T5), horizontally (T25), longitudinally combined horizontally in layers (T25+2.5), and randomly (T2.5). The results showed that compared to CK, T25, T5, and T25+2.5 significantly reduced the infiltration rate of irrigation water, leading to prolonged infiltration times. Wetting front curves under T5, T25+2.5, and T25 exhibited similar inverted "V" shapes, while CK and T2.5 showed fluctuating parallel lines. Water retention in the soil was higher under straw strip treatments (T5, T25, T25+2.5) and straw layer treatment (T2.5) compared to CK after 24 h of the first irrigation. T5 demonstrated the most effective salt removal, surpassing other treatments, with a desalination rate of 97.71%. Additionally, T5 had the highest salt leaching efficiency (SLE) in the 0–20 cm soil layer, recommending it as the optimal form for managing saline soils in crop production due to its simplicity and higher SLE. We found that buried straw strips reduced soil water infiltration rate and wetting front propulsion speed, increased soil water content and enhanced salt leaching efficiency in the saline soil. Our findings provide a basis for developing strategies that improve soil quality and irrigation efficiency, mitigate the effects of salinity on crop production, and ensure food security for a rapidly growing global population. [ABSTRACT FROM AUTHOR]

Owing to the increasing need for green synthesis and environmental protection, the utilization of biological organism‐derived carbons as supports for noble‐metal electrocatalysts has garnered public interest. Nevertheless, the mechanism by which microorganisms generate nanometals has not been fully understood yet. In the present study, we used genetically engineered bacteria of Shewanella oneidensis MR‐1 (∆SO4317, ∆SO4320, ∆SO0618 and ∆SO3745) to explore the effect of surface substances including biofilm‐associated protein (bpfA), protein secreted by type I secretion systems (TISS) and type II secretion systems (T2SS), and lipopolysaccharide in microbial synthesis of metal nanoparticles. Results showed Pd/∆SO4317 (the catalyst prepared with the mutant ∆SO4317) shows better performance than other biocatalysts and commercial Pd/C, where the mass activity (MA) and specific activity (SA) of Pd/∆SO4317 are 3.1 and 2.1 times higher than those of commercial Pd/C, reaching 257.49 A g−1 and 6.85 A m−2 respectively. It has been found that the exceptional performance is attributed to the smallest particle size and the presence of abundant functional groups. Additionally, the absence of biofilms has been identified as a crucial factor in the formation of high‐quality bio‐Pd. Because the absence of biofilm can minimize metal agglomeration, resulting in uniform particle size dispersion. These findings provide valuable mechanical insights into the generation of biogenic metal nanoparticles and show potential industrial and environmental applications, especially in accelerating oxygen reduction reactions. [ABSTRACT FROM AUTHOR]

Karstification plays a crucial role in forming magnificent scenery, and storing oil, natural gas, mineral resources, and water. Through the inspiration of karstification, a hierarchical layered double hydroxide (LDH) with funnel-like and cave-like structures (called Karst-LDH) is formed by the dissolution of acrylic acid/water solution. Meanwhile, the results of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) show that Karst-LDH has complicated and interconnected internal pipe networks. The actual maximum phosphate adsorption capacity of Karst-LDH reaches 126.38 mg g−1 due to the unique structures, protonation, ligand exchange, ion exchange, and hydrogen bonding, which is over ten times that of general LDH with a regular hexagonal structure. The results of isotherms and thermodynamics also indicate that Karst-LDH conforms to more heterogeneous and multilayer adsorption with a higher entropy-driven process. Karst-LDH exhibits good selectivity for chloride and nitrate ions. The change in the frontier orbital interaction between phosphate and different LDHs is a significant reason for quick macropore transmission, mesopore interception, and finally, phosphate storage in Karst-LDH. This work provides an efficient way for the design and fabrication of high adsorption performance materials with unique karst-type structures, which can be used for multiple fields potentially. [ABSTRACT FROM AUTHOR]

Many studies have been conducted on the microbial reduction of Pd (II) to palladium nanoparticles (Pd-NPs) due to the environmental friendliness, low cost, and the decreased toxicity of Pd (II) ions. In this study, we investigate the reduction mechanism of Pd (II) by Bacillus megaterium Y-4 through proteomics. The data are available via ProteomeXchange with identifier PXD049711. Our results revealed that B. megaterium Y-4 may use the endogenous electron donor (NAD(P)H) generated by nirB, tdh, and fabG and reductase to reduce Pd (II) to Pd-NPs. The expression levels of fabG, tdh, gudB, and rocG that generate NAD(P)H were further increased, and the number of reduced Pd-NPs was further increased with the exogenous electron donor sodium formate. Endogenous electron mediators such as quinones and flavins in B. megaterium Y-4 can further enhance Pd (II) reduction. The findings provided invaluable information regarding the reduction mechanism of Pd (II) by B. megaterium Y-4 at the proteome level. [ABSTRACT FROM AUTHOR]

This paper examines a method and scheme for optimizing the allocation of nuclear radiation monitoring resources, based on the analysis of the risk of nuclear security events and the importance of facilities in a spent fuel reprocessing plant. By constructing a nuclear security radiation accident tree for a plant, the importance of different security events was calculated using fuzzy mathematics and expert scoring methods. The importance of each facility was determined by establishing a fuzzy comprehensive decision model, and a resource allocation scheme for nuclear radiation monitoring was proposed based on the importance level of facilities. The research findings demonstrated that the extraction process plant in the main process area, and the centralized control room in the front area of the plant, were of highest importance. Accordingly, three levels of nuclear radiation monitoring programs were established based on the importance of each facility. This study offers theoretical and technical support for the safety management and operation of a spent fuel reprocessing plant. Additionally, the analysis results can serve as a reference for allocating nuclear radiation monitoring resources in various facilities in a reasonable manner. [ABSTRACT FROM AUTHOR]

Dengue virus is an important human pathogen affecting people especially in tropical and subtropical regions. Its genome encodes seven non-structural proteins that are important for viral assembly and replication. Dengue NS2B is a membrane protein containing four transmembrane helices and involved in protein-protein interactions. Its transmembrane helices are critical for location of NS2B on the cell membrane while one cytoplasmic region composed of approximately 40 amino acids serves as a cofactor of viral NS3 protease by forming a tight complex with the N-terminal region of NS3. Here, we report the backbone resonance assignments for a dengue NS2B construct referred to as mini-NS2B containing only the transmembrane regions without NS3 cofactor region in detergent micelles. Mini-NS2B exhibits well-dispersed cross-peaks in the 1H-15N-HSQC spectrum and contains four helices in solution. The available mini-NS2B and its assignment will be useful for determining the structure of NS2B and identifying small molecules binding to the transmembrane regions. [ABSTRACT FROM AUTHOR]

Six novel keratin-based fluorescent hierarchical porous hydrogels, pure keratin (FK), keratin-seaweed (FK-SP), keratin-chitosan (FK-CS), and keratin-rhodamine B (FK-Rh B) with three-dimensional (3D) interconnected network structures have been prepared via a one-pot crosslinking method. The green-red dual emissions of the FK-SP and FK-Rh B hydrogels were observed under a single-wavelength excitation. [ABSTRACT FROM AUTHOR]

RNA‐binding proteins (RBPs) play vital roles in organisms through binding with RNAs to regulate their functions. Small molecules affecting the function of RBPs have been developed, providing new avenues for drug discovery. Herein, we describe the perspectives on developing small molecule regulators of RBPs. The following types of small molecule modulators are of great interest in drug discovery: small molecules binding to RBPs to affect interactions with RNA molecules, bifunctional molecules binding to RNA or RBP to influence their interactions, and other types of molecules that affect the stability of RNA or RBPs. Moreover, we emphasize that the bifunctional molecules may play important roles in small molecule development to overcome the challenges encountered in the process of drug discovery. [ABSTRACT FROM AUTHOR]

Pile driving in marine engineering causes a vibration response in the surrounding soil and adjacent piles, which may affect the safety of adjacent structures supported by the pile foundation and the internal equipment of the adjacent structures. Therefore, for the safe completion of a project, it is of great significance to study the ground and the pile vibrations induced by pile driving. Based on measurement data from a Rudong wind farm engineering in Jiangsu Province, a numerical model of the vibration response induced by pile driving was established. Based on various methods of calculating pile driving loading, the influence of pile driving loading characteristics on the vibration response was analyzed. Furthermore, the influence of pile driving on the acceleration of the ground and adjacent piles was studied, including the impacts of the distance between the driving pile, the existing pile and the driving depth. The results show that the acceleration of the ground has a good linear relationship with the distance in the logarithmic coordinate system, and the acceleration of the existing pile attenuates with an increasing driving depth of the driving pile. A simplified evaluation method for the peak acceleration response of adjacent sites impacted by pile driving was proposed, which provides a reference for ocean engineering construction in the Huangsha Ocean area of China. [ABSTRACT FROM AUTHOR]

Oligodendrocytes generate myelin sheaths vital for the formation, health, and function of the central nervous system. Mounting evidence suggests that receptor tyrosine kinases (RTKs) are crucial for oligodendrocyte differentiation and myelination in the CNS. It was recently reported that discoidin domain receptor 1 (Ddr1), a collagen-activated RTK, is expressed in oligodendrocyte lineage. However, its specific expression stage and functional role in oligodendrocyte development in the CNS remain to be determined. In this study, we report that Ddr1 is selectively upregulated in newly differentiated oligodendrocytes in the early postnatal CNS and regulates oligodendrocyte differentiation and myelination. Ddr1 knock-out mice of both sexes displayed compromised axonal myelination and apparent motor dysfunction. Ddr1 deficiency alerted the ERK pathway, but not the AKT pathway in the CNS. In addition, Ddr1 function is important for myelin repair after lysolecithin-induced demyelination. Taken together, the current study described, for the first time, the role of Ddr1 in myelin development and repair in the CNS, providing a novel molecule target for the treatment of demyelinating diseases. [ABSTRACT FROM AUTHOR]

Dynamic uncertainties and unknown disturbances will degrade the tracking performance of robots. When using a disturber observer-based controller, the key to effectively compensate for these uncertainties is to measure or estimate as accurately as possible any disturbance. To relax restrictions on the design of the current nonlinear disturbance observer for the robot, a universal nonlinear disturbance observer is proposed for higher estimation performance. The stability of the proposed universal nonlinear disturbance observer is theoretically analyzed and the boundaries of estimation error are proven according to the vector differential equation. Finally, the proposed universal nonlinear disturbance observer is evaluated via simulation by comparison to the nonlinear disturbance observer. The result shows a faster estimation speed and a higher estimation accuracy of the universal nonlinear disturbance observer. [ABSTRACT FROM AUTHOR]

Voltage-gated calcium currents and potassium currents were shown to undergo developmental changes in postnatal human and animal cardiomocytes. However, so far, there is no evidence whether sodium currents also presented the developmental changes in postnatal human atrial cells. The aim of this study was to observe age-related changes of sodium currents between pediatric and adult atrial myocytes. Human atrial myocytes were acutely isolated and the whole-cell patch clamp technique was used to record sodium currents isolated from pediatric and adult atrial cardiomocytes. The peak amplitude of sodium currents recorded in adult atrial cells was significantly larger than that in pediatric atrial myocytes. However, there was no significant difference of the activation voltage for peak sodium currents between two kinds of atrial myocytes. The time constants for the activation and inactivation of sodium currents were smaller in adult atria than pediatric atria. The further study revealed that the voltage-dependent inactivation of sodium currents were more slow in adult atrial cardiomyocytes than pediatric atrial cells. A significant difference was also observed in the recovery process of sodium channel from inactivation. In summary, a few significant differences were demonstrated in sodium currents characteristics between pediatric and adult atrial myocytes, which indicates that sodium currents in human atria also undergo developmental changes.