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Seventeen strains of LAB (lactic acid bacteria) were screened for their ability to form ZnPP (zinc protoporphyrin) by measuring fluorescence intensity. Three strains (Weissella viridescens JX11, Weissella viridescens MDJ8, and Lactobacillus pentosus Q) exhibited notable ZnPP-forming ability. The ferrochelatase enzyme activity of W. viridescens JX11 was significantly higher than that of the other two strains (p < 0.05). The three selected strains were then inoculated into minced meat to observe their effect on color development and quality properties. The a*-values of the bacteria-inoculated groups were significantly higher than those of the control group and lower than those of the nitrite group (p < 0.05). The visible bright red color of the inoculated groups was stronger than that of the control and inferior to the nitrite group, especially in cooked minced meat. The fluorescence intensities in inoculated groups were significantly higher than those of the control and nitrite groups (p < 0.05). The UV–Vis absorbance data at 417 nm indicated that inoculated groups exhibited higher absorbance compared to the control group (p < 0.05). These results indicate that high ZnPP-forming bacteria can enhance the color of meat products and these have certain potential to replace nitrite in meat products. [ABSTRACT FROM AUTHOR]

In the process of ship production, the production of pipeline occurs throughout the production process. Key issues to address in the pipeline-processing workshop of a shipyard include uneven production loads and weak flow rhythmicity. Additionally, uncertainties in processing time and other real-world factors can pose significant challenges. The fuzzy number method is used to describe processing and completion times, with the goal of minimizing the fuzzy maximum completion time. To achieve this, a scheduling method based on the Black Widow Optimization Algorithm (BWOA) is proposed for the pipeline-processing workshop in a shipyard. This algorithm aims to effectively reduce the blindness of the production plan, ensure the rationality and stability of the plan, shorten the production cycle of a ship pipeline, improve the production efficiency, and realize the lean shipbuilding mode. A simulation was conducted to evaluate the BWOA algorithm. The final simulation test results show that the algorithm provided a better scheduling plan and a stabler average value than comparable methods, which proves its effectiveness in the scheduling of pipeline processing in shipyards. [ABSTRACT FROM AUTHOR]

Welding technology plays a vital role in the manufacturing process of ships, automobiles, and aerospace vehicles because it directly impacts their operational safety and reliability. Hence, the development of an accurate system for identifying welding defects in arc welding is crucial to enhancing the quality of welding production. In this study, a defect recognition method combining the Neighborhood Rough Set (NRS) with the Dingo Optimization Algorithm Support Vector Machine (DOA-SVM) in a multisensory framework is proposed. The 195-dimensional decision-making system mentioned above was constructed to integrate multi-source information from molten pool images, welding current, and vibration signals. To optimize the system, it was further refined to a 12-dimensional decision-making setup through outlier processing and feature selection based on the Neighborhood Rough Set. Subsequently, the DOA-SVM is employed for detecting welding defects. Experimental results demonstrate a 98.98% accuracy rate in identifying welding defects using our model. Importantly, this method outperforms comparative techniques in terms of quickly and accurately identifying five common welding defects, thereby affirming its suitability for arc welding. The proposed method not only achieves high accuracy but also simplifies the model structure, enhances detection efficiency, and streamlines network training. [ABSTRACT FROM AUTHOR]

The Northeast China Block is a major component of the Central Asian Orogenic Belt, and its tectonic evolution has attracted much research attention. Ordovician strata are important in reconstructing the tectonic evolution of the Northeast China Block. This paper presents the results of sedimentological, zircon U–Pb, and geochemical analyses of sandstones of the Luohe Formation in the Wunuer area, Northern Great Xing'an Range, Northeast China. Lithological data, sedimentary structures, and grain-size analysis indicate that the Luohe Formation was deposited in a shallow marine environment. Detrital zircon U–Pb dating yields age peaks of 463, 504, 783, 826, 973, and 1882 Ma for sandstones from the Luohe Formation. The youngest zircon grain age of 451 ± 6 Ma represents the maximum depositional age of the Luohe Formation. The peak age at 463 Ma is consistent with the timing of post-collisional magmatism and the formation of the Duobaoshan island arc, while the peak at 504 Ma is consistent with the timing of magmatic activity related to the collision between the Erguna and Xing'an blocks. The peaks at 788, 826, 973, and 1882 Ma correspond to magmatism in the Erguna block, these ages indicate that the sandstones of the Luohe Formation were derived mainly from the Erguna block. Sandstone modal compositional analysis indicates that the provenance of the Luohe Formation was mainly a magmatic arc. The geochemical compositions of the sandstones suggest that the source rocks have continental island arc signatures. Based on the depositional age, sedimentary environment, provenance, and regional geology, it is concluded that the Luohe Formation was deposited in a back-arc basin setting during the formation of the Duobaoshan island arc–basin system in response to subduction of the Paleo-Asian oceanic plate. [ABSTRACT FROM AUTHOR]

In this study, we introduce a novel framework for the semantic segmentation of point clouds in autonomous driving scenarios, termed PVI-Net. This framework uniquely integrates three different data perspectives—point clouds, voxels, and distance maps—executing feature extraction through three parallel branches. Throughout this process, we ingeniously design a point cloud–voxel cross-attention mechanism and a multi-perspective feature fusion strategy for point images. These strategies facilitate information interaction across different feature dimensions of perspectives, thereby optimizing the fusion of information from various viewpoints and significantly enhancing the overall performance of the model. The network employs a U-Net structure and residual connections, effectively merging and encoding information to improve the precision and efficiency of semantic segmentation. We validated the performance of PVI-Net on the SemanticKITTI and nuScenes datasets. The results demonstrate that PVI-Net surpasses most of the previous methods in various performance metrics. [ABSTRACT FROM AUTHOR]

The coexistence of urban expansion and shrinkage in China has become increasingly apparent; therefore, the current strategic model of growth-oriented urban planning as the top-level design needs to be adjusted. This paper focuses on the city of Baishan, which is a typical shrinking city in China, and explores the feasibility of implementing the concept of smart shrinkage planning in shrinking cities in China by constructing a coupled PLUS-SD model. The results demonstrate the following conclusions: (1) The overall simulation of the coupled PLUS-SD model is superior to that of the PLUS model. In Baishan, the areas with the most changes in construction land will be located at the edges of the landforms by 2030. (2) Using the traditional planning scenario would only exacerbate the rate of construction land expansion in Baishan, deepening the incongruity between the city's population and construction land. (3) The smart shrinkage scenario will require strict control of the scale of construction land and optimization of the structure of the urban construction land, which would push the city in the direction of healthy and sustainable development. (4) The concept of smart shrinkage planning is a scientific and feasible plan for realizing the efficient and sustainable use of construction land in shrinking cities. [ABSTRACT FROM AUTHOR]

The establishment of the correspondence between the important features of the topside weld pool and the penetration state is a key link in penetration control. This article presents a scheme of variable gap welding penetration control based on rough-fuzzy modeling. By utilizing the basic concepts of variable precision rough sets and conditional information entropy, relevant algorithms for attribute reduction and rule extraction in decision information systems are addressed. Raw data for modeling are obtained through current–gap combination experiments, and then rough-set-based knowledge acquisition algorithms are used to generate classification rules for the penetration state. Based on the correspondence between the important features of the topside pool and the penetration state, a fuzzy control model is established. Welding experiments under variable gaps are conducted to examine the proposed control scheme, and the results indicate that the weld has good penetration and meets the requirements of welding specifications. [ABSTRACT FROM AUTHOR]

Considering the nonlinear, time-varying, and multivariate coupling nature of the welding process, achieving excellent control of the welding process can be challenging. In addition, welding experience varies from person to person, making it difficult to establish a uniform standard. In this work, rough set theory is introduced and applied to arc welding process modeling and quality control to achieve effective online control of weld penetration during welding. A variable precision neighborhood rough-fuzzy method is proposed to enhance the efficiency and adaptability of rough set theory for information processing in the welding process. By designing welding experiments with different gaps and currents, descriptors such as the tail area coefficient and the length-width ratio of the melt pool have been proposed to characterize the melt pool. Rough set theory has been used to extract decision classification rules for welding percolation state information, and clustering analysis, fuzzy logic, and min-max fuzzy methods have been introduced for knowledge modeling. The proposed variable precision neighborhood rough-fuzzy control model is verified via three sets of experiments, and the results show that the model has excellent stability and effectiveness. [ABSTRACT FROM AUTHOR]

Northeast China composes the main part of the Central Asian Orogenic Belt. Traditionally, Northeast China has been considered a collage of several microcontinental blocks. However, the tectonic evolution of these blocks remains uncertain. Igneous rocks can be used to infer the magmatic histories of the blocks and thus help reconstruct their evolution. In this study, we present new zircon U–Pb and whole-rock geochemical data for Carboniferous igneous rocks from the Wunuer area, northern Great Xing'an Range, Northeast China, to constrain the Carboniferous amalgamation of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs. On the basis of zircon U–Pb dating results, we identify two main stages of magmatism, i.e., early Carboniferous (332–329 Ma) and late Carboniferous (312–310 Ma). The early Carboniferous igneous rocks include diorites and granodiorites, with the former being classified as calc-alkaline to tholeiitic and the latter as tholeiitic. Both rock types are enriched in Th and U and depleted in Nb and Ti. The rocks display slightly fractionated rare earth element (REE) patterns, with an enrichment in light REEs and a depletion in heavy (H)REEs. The geochemical characteristics of the early Carboniferous rocks indicate that they formed in a subduction-related continental-arc setting. The late Carboniferous igneous rocks include monzogranites and syenogranites, both of which are classified as high-K calc-alkaline rocks and show enrichment in Th, U, and Rb and depletion in Nb and Ti. The rocks display strongly fractionated REE patterns, with an enrichment in light REEs and a depletion in HREEs. The geochemical characteristics of the late Carboniferous rocks indicate that they formed in a syn-collisional tectonic setting. Combining the new geochronological and geochemical results and inferred tectonic settings with regional magmatic data, we propose a new three-stage model to interpret the late Paleozoic tectonic evolution of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs of Northeast China: (1) early Carboniferous (360–340 Ma) subduction of the Paleo-Asian oceanic plate beneath the united Xing'an–Erguna Massif and formation of the Wunuer oceanic basin in the Yakeshi area; (2) early to late Carboniferous (340–310 Ma) sustained subduction of the Paleo-Asian oceanic plate beneath the united Xing'an–Erguna Massif and initiation of subduction of the Wunuer oceanic basin; and (3) late Carboniferous–early Permian (310–275 Ma) syn-collisional to post-collisional tectonic transition between the united Xing'an–Erguna Massif and the Songnen–Zhangguangcai Range Massif. [ABSTRACT FROM AUTHOR]

Northeast China occupies the majority of the eastern Central Asian Orogenic Belt, which mainly consists of continental blocks and accretionary terranes. The Devonian was a tectonic quiet period in the NE China region due to a lack of tectono-magmatism, but the tectonic background of this period has been unclear, especially for the Hegenshan-Heihe Suture between Xing'an and Songliao accretionary terranes, which represents the Paleozoic Nenjiang Ocean (a branch ocean of the eastern Paleo-Asian Ocean). Here we report granitic rocks from the Woluohe area, Northern Great Xing'an Range, NE China, to constrain the tectonic process of the transition from the Devonian quiet period to the Early Carboniferous active tectonic period. Three granitic rock samples produce zircon U-Pb ages of 389 Ma, 368 Ma, and 351 Ma, belonging to the Middle and Late Devonian and Early Carboniferous, respectively. They have high Si, Al, K, and Na contents, but with low Mg, Fe, and Ti contents, together with positive Hf isotopic features and low molar Al2O3/(MgO+FeOT) ratios, we suggest that they were derived from partial melting of lower crustal igneous rocks. Meanwhile, the narrow major element variation at odd with the fractionation process and their negative Nb and Ta anomalies imply the obvious contribution of crustal. Comprehensive tectonic setting analysis shows all samples are in calc-alkali magmatic series with rightward fractionated REE and trace element patterns that are enriched in LREE and LILE and depleted in HREE and HFS, indicating a subduction-related magmatic arc setting. Considering the regional tectonic setting and the small scale of the Devonian plutons, we suggest a limited subduction tectonic setting during the quiet period of the northern Great Xing'an Range, which might indicate the beginning of an initial northwestward subduction of the Nenjiang Oceanic lithosphere beneath the Xing'an Accretionary Terrane in the Middle Devonian, accelerated subduction in the Late Devonian, and bidirectional subduction in the Early Carboniferous. [ABSTRACT FROM AUTHOR]

Welding is an important production and processing method in industrial production. Due to the uncertainty of its process and the complexity of its mechanism, it is challenging to construct an accurate welding process parameter model to describe it. Fuzzy interpolation reasoning is a valuable tool in the realm of intelligent systems. It helps to reduce the complexity of fuzzy models and can be used for reasoning in fuzzy systems with sparse rule bases. This paper provides an interpolation reasoning method that combines fuzzy set distance and similarity. The proposed method is applied to welding forming predictions, and welding penetration is predicted by the given welding current and speed. The results show that the algorithm has high calculation accuracy. [ABSTRACT FROM AUTHOR]

Shrinking cities are a class of cities that show different trajectories in the urbanization process. Although many studies have examined shrinking cities from multi-dimensional perspectives, the spatiotemporal evolution of land use structure is still poorly understood. This study constructed an analysis framework for spatiotemporal evolution characteristics of land use structure over two 10-year periods based on 334 county-level administrative units in the context of northeast China, a region undergoing substantial population loss and urban shrinkage. This study analyses quantitatively measured population loss and land use conversion and investigated the rationality of the expansion mode of newly added construction land in research units. The results demonstrated that, first, the total population in northeast China continued to decline, but the total construction area continued to grow, and the various types of construction land in most shrinking units did not decline with the loss of population. Second, 67.09% of new construction land came from cropland, and compared with 2000–2010, the growth of new construction land in 2010–2020 slowed down. Third, during the study period, more than half of the expansion area for newly added construction land came from sprawling expansion, and areas in a state of shrinking were no exception. [ABSTRACT FROM AUTHOR]

The NH3 uniformity and conversion rate produced by the urea–water solution spray system is an essential factor affecting de-NOx efficiency. In this work, a three-dimensional simulation model was developed with the CFD software and was employed to investigate the effects of two typical injection methods (wall injection and center injection) and three distribution strategies (pre-mixer, post-mixer, pre-mixer, and post-mixer) of two typical mixers on the urea conversion rate and uniformity. The field synergy principle was employed to analyze the heat transfer of different mixer flow fields. The results show that the single mixer has instability in optimizing different injection positions due to different injection methods and injection positions. The dual-mixer is stable in the optimization of the flow field under different conditions. The conclusion of the field synergy theory of the single mixer accords with the simulation result. The Fc of the dual-mixer cases is low, but the NH3 conversion and uniformity index rate are also improved due to the increase in the residence time of UWS. [ABSTRACT FROM AUTHOR]

Since current key management schemes are mainly designed for static and planar networks, they are not very suitable for the layer-cluster wireless sensor networks (WSNs), a WSN layer-cluster key management scheme based on quadratic polynomial and Lagrange interpolation polynomial is proposed, in which the main idea of this scheme along the research line of broadcast identity authentication, session key, group key, network key and personal key. Specifically, authentication key can be established on the basis of Fourier series for identity authentication; session key is established by a multiple asymmetric quadratic polynomial, in which session key information is encrypted by the authentication key to ensure the security of intermediate interactive information; based on the former two keys, group key is established on the basis of Lagrange interpolation polynomial, in which the nodes of the cluster are not directly involved; the generation and management of network key is similar to the group key, in which the establishment idea is to regard the BS and all cluster heads as a group; the generation and management of personal key is also similar to the group key, the difference is that the personal key can be obtained by cluster nodes through getting the Lagrange interpolation polynomial coefficients based on their own random key information. It is analyzed that the proposed layer-cluster key management scheme can guarantee the identity of network nodes firstly through forward authentication and reverse authentication, and session key, group key and network key will guarantee the independence of the keys' management and avoids the problem of single point failure compared with LEAP protocol, and personal key will guarantee the privacy of network. [ABSTRACT FROM AUTHOR]

Indoleamine 2,3-dioxygenase 1 (IDO1) is a heme-containing intracellular enzyme that catalyzes the first and rate-determining step of tryptophan metabolism and is an important immunotherapeutic target for the treatment of cancer. In this study, we designed and synthesized a new series of compounds as potential IDO1 inhibitors. These compounds were then evaluated for inhibitory activity against IDO1 and tryptophan 2,3-dioxygenase (TDO). Among them, the three phenyl urea derivatives i12, i23, i24 as showed potent IDO1 inhibition, with IC50 values of 0.1–0.6 μM and no compound exhibited TDO inhibitory activity. Using molecular docking, we predicted the binding mode of compound i12 within IDO1. Compound i12 was further investigated by determining its in vivo pharmacokinetic profile and anti-tumor efficacy. The pharmacokinetic study revealed that compound i12 had satisfactory properties in mice, with moderate plasma clearance (22.45 mL/min/kg), acceptable half-life (11.2 h) and high oral bioavailability (87.4%). Compound i12 orally administered at 15 mg/kg daily showed tumor growth inhibition (TGI) of 40.5% in a B16F10 subcutaneous xenograft model and 30 mg/kg daily showed TGI of 34.3% in a PAN02 subcutaneous xenograft model. In addition, the body weight of i12-treated mice showed no obvious reduction compared with the control group. Overall, compound i12 is a potent lead compound for developing IDO1 inhibitors and anti-tumor agents. [ABSTRACT FROM AUTHOR]

Using polyethylene glycol as a mesoporous soft template, a series of hierarchically porous ZSM-5 zeolites were prepared. X-ray diffraction, infrared spectroscopy, N2 adsorption–desorption, and transmission electron microscopy results demonstrated that the resultant materials contained a micro–mesoporous structure. Since the existence of mesoporous structure favors the diffusion of large molecular reactants and products, the phenol conversion and selectivity to 2,4-Di-TBP on the hierarchical ZSM-5 zeolite can be improved for the alkylation of phenol with tert-butanol. [ABSTRACT FROM AUTHOR]

Precise displacement sensors are an important topic in precision engineering. At present, this type of sensors typically have a single feature of either translation or rotation measurement. They are also inconvenient to integrate with the host devices. In this report we propose a new kind of sensor that enables both translation and rotation measurement by using the combined effect of magnetostriction and piezoelectricity. As a proof of concept, we experimentally realized a prototype of non-contact translation-rotation precise sensor. In the current research stage, through both theoretical and experimental study, the non-contact displacement sensor is shown to be feasible for measuring both translation and rotation either in coarse or fine measurement. Moreover, owing to its compact, rigid structure and fewer components, it can be easily embedded in host equipment.