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γ-TiAl alloy is a typically difficult material to machine, and machining defects such as grain pull-out and material spalling are common during machining, resulting in component scrap. As a result, it is critical to investigate the real-time monitoring method of surface roughness during milling. A new model for predicting surface roughness is proposed in this article. Based on the idea of deep learning, the prediction problem of surface roughness is turned into a classification problem. The features of the force signal are extracted using a continuous wavelet transform, and the one-dimensional signal is converted into a two-dimensional time-frequency diagram to obtain more information. The transfer learning mechanism is introduced to make the model run faster and improve prediction accuracy. The overfitting problem is solved and the model's generalization ability is improved through batch normalization and dropout layer, and the prediction accuracy is increased by 3%. The results show that the method has high recognition accuracy, with a maximum classification accuracy of 98% and an average accuracy of 96.12%, a 6% improvement over the traditional model, allowing it to accurately realize real-time monitoring of surface quality in milling processing.

Icariin (ICA) is the main active component of the traditional Chinese medicine Epimedium, which has been confirmed to play a neuroprotective role in spinal cord injury (SCI) models. Astrocyte activation is a key link in “inflammatory storms” after SCI, and eventually form glial scar to inhibit neurological recovery. Studies have shown that icariin can effectively inhibit inflammatory response and promote the recovery of nerve function after SCI, but the specific mechanism is still unclear. This study applied network pharmacology and in vivo experimental verification to explore the molecular mechanism of ICA in the treatment of SCI. A total of 37 targets were screened out, mainly enriched in response to hypoxia, response to abiotic stimulus, regulation of cellular response to stress, and the TGF-beta signaling pathway etc. In the animal experiments, the Basso, Beattie and Bresnahan scores and Hematoxylin Eosin staining revealed that ICA could effectively improve the behavioral and histological recovery of SCI rats. Then ICA was confirmed to reduce astrocyte GFAP, Vimentin, and the expression of Ki-67 after SCI. Furthermore, ICA could inhibit the TGF-beta signaling pathway. ICA could also inhibit the expression of Yap protein. However, when Yap protein was activated, ICA inhibited the TGF-beta signaling pathway and reactive astrocyte activation was reversed. To sum up, the mechanism of ICA treatment for SCI may involve the inhibition of reactive astrocyte activation by inhibiting the expression of Yap protein and down-regulating the TGF-beta signaling pathway.

In order to solve the problems of timeliness and accuracy in the performance analysis of complex product assembly, taking the performance analysis of the array antenna assembly process as the research object, and taking the assembly process performance "measurable" as the requirement, a digital twin modeling method for the assembly performance analysis of the array antenna is proposed. This method integrates finite element, mesh model simplification and surrogate model. In order to realize the real-time prediction and rapid visualization of the assembly performance in the assembly process, a mesh simplification algorithm for finite element mesh model based on edge collapse is proposed and a Gaussian process regression surrogate model for product assembly performance is constructed in order to complete the construction of a digital twin model for assembly performance analysis. Finally, the proposed method is verified by an example of the assembly performance analysis of a typical array antenna. The result shows that the digital twin model proposed has high response speed and fidelity in the analysis of assembly performance, and has certain reference value and significance for the application of digital twin technology in the product assembly process.

Purpose This paper aims to take International SPOrt (ISPO) as a typical case to study how exhibition organizers can reshape their relationship with users through business model innovation to answer the question that how enterprises can help the exhibition industry to upgrade and develop through business model innovation in the internet environment. Design/methodology/approach Faced with the development of internet technology, the impact of online platforms, the relationship between exhibition organizers and their customers are facing unprecedented challenges. On the basis of the literature review, this study analyzed the innovation of exhibitors’ business model from three modules: value proposition, revenue logic and cost base and how to reshape their interaction with users through innovation. This study systematically analyzed the innovation of the ISPO business model and the process of reshaping its relationship with users and dynamic interaction with a single case study method. Findings The main conclusions are as follows: the starting point of reshaping the relationship between exhibition organizer and users in the internet era is to re-understand the needs of customers, the key point of reshaping the relationship is to further cultivate the industrial value and the sustainability of the relationship lies in the customer life cycle management. Originality/value From the perspective of exhibition organizers filling the gap of case study in the field of the exhibition. In the area of the exhibition, previous studies rarely started from the perspective of exhibition organizers, but, this paper discusses the interaction between exhibition organizers, exhibitors and visitors from this perspective in this study.

In order to solve the problem of unmeasurable assembly performance of complex product, the digital twin-driven assembly quality control and prediction of complex product is studied by means of cyber-physical fusion in the assembly workshop. The connotation of digital twin intelligent assembly is introduced, the current research status of complex product assembly quality is compared and analyzed, and three main key technologies for the assembly quality control of complex product are proposed: (1) multidimensional, multi-scale, multidisciplinary modeling and simulating of digital twin-driven assembly; (2) multi-source heterogeneous data collection, sensing and fusion for assembly processes; (3) data-driven decision making, feedback and optimization technology. Finally, the application of digital twin technology in the field of assembly quality control of complex product is prospected.

Nowadays it is commonly accepted that knowledge, as a resource has become increasingly important in the drive toward knowledge-driven innovation in the manufacturing industry, and which is especially critical for the research and development of complex equipment. In China, there are several fields of manufacturing, such as aviation, ship, and electronics. Although each of them has its own professional technology, they also take advantage of the basic common manufacturing technology. Thus, it is meant for sharing manufacturing technology knowledge. In order to promote innovation, a manufacturing technology knowledge retrieval system is developed to make more efficient use of manufacturing technology knowledge. Manufacturing technology knowledge is a phrase with vast meanings, which may include knowledge of different manufacturing process means, machine, and process capabilities or the latest technology developments. In this system, the manufacturing technology knowledge is defined and organized. A knowledge retrieval method based on the weighted fusion of ontology-based semantic extension (OSE) and user-based collaborative filtering (UCF) is proposed and described detailed. On this basis, the prototype system of manufacturing technology knowledge retrieval system is developed. Its architecture and main functions are elaborated. The results of this system facilitate the sharing of manufacturing knowledge, and it is expected to accelerate the process of knowledge transfer, to improve the level of the overall manufacturing technology.

The present study examined how decision-making is affected by first (L1) and second languages (L2), emotion, and cognitive load. In a cross-task study, 30 Chinese-English bilinguals were asked to implement lexical-semantic judgment and gambling task. The results showed that after lexical decisions under high cognitive load, P3 was more positive for negative words than for neutral words in L1. The reverse was the case in the L2 in which P3 was more positive for neutral words compared to negative words. Critically, under high cognitive load, as the P3 effect increased for negative words relative to neutral words, the rationality of the decisions after these negative words decreased in the L1 but increased in the L2. The results moreover revealed that the increased Granger causal strength predicted more rational choices in the L2 high-load negative condition. Altogether, the findings offer evidence of how L1s and L2s can differentially influence rational decision-making.

With the exhibition sector becoming increasingly important for the hospitality and tourism industry, it is critical to understand what drives the success of an exhibition. Through a comprehensive literature review, we first identified two broad categories of factors, namely exhibition attributes and exhibitor perceptions, that influence exhibitor satisfaction and loyalty. Next, a meta-analysis was conducted based on 26 empirical papers studying the Chinese exhibition market to quantitatively evaluate these relationships. The results show that among the exhibition attributes, booth management, service personnel, and exhibition environment are the most important factors affecting exhibitor satisfaction, while exhibition brand is the most important factor affecting loyalty. Among exhibitor perceptions, service quality is more important for satisfaction, while perceived value is more meaningful to loyalty. This study offers insights into strategies for exhibition organizers to cultivate long-term relationships, and to better cope with the challenges of emerging forces such as the Internet. Published version

Prior work investigated how foreign language impacts decision making by either reducing access to emotion or imposing additional cognitive demands. In this fMRI study, we employed a cross-task design to assess at the neural level whether and how the interaction between cognitive loading and emotional involvement is affected by language (native L1 vs. foreign L2). Participants completed a Lexico-semantic task where in each trial they were presented with either a neutrally or a negatively valenced word either in L1 or L2, and either under cognitive loading or not. After each trial, they had to decide whether to take a risky decision within a gambling game. During the Gamling task, left amygdala and right insula were more activated after having processed a negative word under cognitive loading. However, this was true for L1 but not for L2, suggesting that cognitive loading was germane and facilitated rather than hindered access to emotion only in L1. Further suggesting that cognitive load can enhance emotional sensitivity in L1 but not in L2, we found that functional connectivity between reward-related striatum and right insula increased under cognitive loading only in L1. Overall, results suggest that cognitive loading in L1 can favor access to emotion and lead to a more impulsive decision making, whereas cognitive loading in L2 can attenuate access to emotion and lead to a more rational decision making.

Three-dimensional ordered macroporous NiFe2O4 (3DOM-NFO) powder was synthesized through the direct templating method combined with the sol–gel combustion technique. Polymethyl methacrylate (PMMA) spheres with different sizes were used as the hard templates. In order to understand the effect of PMMA spheres mean size on the structure and catalytic activity of synthesized 3DOM-NFO, the detailed characterization of the material was carried out by XRD, SEM, BET, XPS, UV–VIS, and DRS techniques. Direct hydrogeneration production of CH4 from CO2 and H2O was used to evaluate the catalysis performance of 3DOM-NFOs. The production of CH4 evolution can reach 1040.8 μmol/g at 350 °C and ambient pressure when 300 nm template was used. It was concluded that the specific surface area and moderate concentration of oxygen vacancies are the crucial factors affecting the catalysis properties. Reasonably high turnover number of 0.244 and high CH4 conversion efficiency of 0.897% were obtained in this study. 3DOM-NFO can be a promising catalyst for hydrocarbon fuel production by directly using CO2 and H2O as the safe and cheap feedstocks.

Embryonic stem (ES) cells provide an invaluable tool for molecular analysis of vertebrate development and a bridge linking genomic manipulations in vitro and functional analysis of target genes in vivo. Work towards fish ES cells so far has focused on zebrafish (Danio renio) and medaka (Oryzias latipes). Here we describe the derivation, pluripotency, differentiation and growth responses of ES cell lines from Nile tilapia (Oreochromis niloticus), a world-wide commercial farmed fish. These cell lines, designated as TES1-3, were initiated from blastomeres of Nile tilapia middle blastula embryos (MBE). One representative line, TES1, showed stable growth and phenotypic characteristics of ES cells over 200 days of culture with more than 59 passages under feeder-free conditions. They exhibited high alkaline phosphatase activity and expression of pluripotency genes including pou5f3 (the pou5f1/oct4 homologue), sox2, myc and klf4. In suspension culture together with retinoic acid treatment, TES1 cells formed embryoid bodies, which exhibited expression profile of differentiation genes characteristics of all three germ cell layers. Notably, PKH26-labeled TES1 cells introduced into Nile tilapia MBE could contribute to body compartment development and led to hatched chimera formation with an efficacy of 13%. These results suggest that TES1 cells have pluripotency and differentiation potential in vitro and in vivo. In the conditioned DMEM, all of the supplements including the fetal bovine serum, fish embryonic extract, fish serum, basic fibroblast growth factor and non-protein supplement combination 5N were mitogenic for TES1 cell growth. This study will promote ES-based biotechnology in commercial fish.

Prior work has reported that foreign language influences decision making by either reducing access to emotion or imposing additional cognitive demands. In this fMRI study, we employed a cross-task design to assess at the neural level whether and how the interaction between cognitive load and emotional involvement is affected by language (native L1 vs. foreign L2). Participants completed a Lexico-semantic task where in each trial they were presented with a neutrally or a negatively valenced word either in L1 or L2, either under cognitive load or not. We manipulated cognitive load by varying the difficulty of the task: to increase cognitive demands, we used traditional characters instead of simplified ones in L1 (Chinese), and words with capital letters instead of lowercase letters in L2 (English). After each trial, participants decided whether to take a risky decision in a gambling game. During the Gamling task, left amygdala and right insula were more activated after having processed a negative word under cognitive load in the Lexico-semantic task. However, this was true for L1 but not for L2. In particular, in L1, cognitive load facilitated rather than hindered access to emotion. Further suggesting that cognitive load can enhance emotional sensitivity in L1 but not in L2, we found that functional connectivity between reward-related striatum and right insula increased under cognitive load only in L1. Overall, results suggest that cognitive load in L1 can favor access to emotion and lead to impulsive decision making, whereas cognitive load in L2 can attenuate access to emotion and lead to more rational decisions.

NiFe2O4 nanoparticles with a high concentration of oxygen vacancies were synthesized via a solvothermal route. The morphology and oxygen vacancies of the catalyst was changed by adjusting the ratio of ethylene glycol (EG) in the mixture solvent. Water was used as a hydrogen source, the thermal catalytic performance of NiFe2O4 was up to 357.6 μmol g−1 of CH4 evolution under low temperature conditions. These findings may further broaden the horizon for CO2 reduction using the oxygen nonstoichiometry strategy.

Different morphologies of SrTiO3/TiO2 heterostructures like nanocubes, nanoparticles, nanospheres, and nanofibers were synthesized via a facile hydrothermal process using TiO2 as both a template and precursor in Sr(OH)2 solution. Their structure, interface and composition can be rationally tailored by simply adjusting the Sr(OH)2/TiO2 (Sr/Ti) mole ratios and the morphology of SrTiO3/TiO2 heterostructures can be controlled easily using TiO2 with different morphologies. A SrTiO3 crystal thin layer was grown on an anatase TiO2 substrate to fabricate a heterostructure interface contact between SrTiO3 and TiO2 and the lattice mismatch had an effect on the electrical transport properties. The SrTiO3/TiO2 heterostructures are beneficial for the fast separation of photogenerated electrons and holes so as to suppress the recombination of photogenerated electrons and holes at the interface of SrTiO3 and TiO2. Besides this, the different morphologies of the SrTiO3/TiO2 heterostructures allowing facile electron transfer, the hierarchical structure promoting mass transfer and allowing more light reflection and absorption, and the large specific surface area providing more reaction sites to facilitate the reactants to the desired oxidation places all together create a synergistic effect to improve the photocatalytic activity of the hierarchical SrTiO3/TiO2 heterostructures. Under the irradiation of UV light, in a water/methanol sacrificial reagent system, the SrTiO3/TiO2 NP heterostructures at a Sr/Ti mole ratio of 40% with the highest BET and smallest crystallite size achieve the highest photocatalytic activity generating 0.731 mmol of H2. The SrTiO3/TiO2 heterostructures exhibit better photocatalytic activity by generating three times more H2 than bare TiO2 and pure SrTiO3.

The ultrafast optical nonlinearity of a pyrazine-based N-heteroacene (Py-0-TQ) is systematically investigated via Z-scan, optical limiting and transient absorption spectrum. Reverse saturable absorption at visible wavelengths is observed. Further study on excited-state kinetics indicates that the strong nonlinear optical (NLO) absorption originates from the cooperating effect between different NLO mechanisms including excited-state absorption (ESA) and two-photon absorption (TPA). Structure-property relation is analyzed, result indicates that the central π-system in Py-0-TQ plays a key role in the cooperating effect via providing a broadband, long-lived ESA and an enhanced TPA as trigger. The experimental and theoretical studies suggest that pyrazine-based N-heteroacene molecules with proper design may have great potential in NLO applications.

The differences in texture and motion between man-made object and natural scene are the key features for human biological visual system to detect moving object in scenery. The paper proposed a moving target detection approach based on spatio-temporal perception, which is a crucial function of the visual attention mechanism. The spatial feature including edge, orientation, texture and contrast of the image are extracted, and then the corresponding spatial salient map are constructed by fusing the features through difference of Gaussian (DOG) function, which can suppress the common and enhance the difference of local region. Then, the global motion, local motion and relative motion between continuous images are extracted by means of pyramid multi-resolution, and the moving salient map is constructed after the motion difference between moving target and background is confirmed. Finally, the spatio-temporal salient map is constructed by fusing the spatial salient map and the moving salient map through competition strategy, and the moving target could be detected by searching the maximum in the spatio-temporal salient map. Some experiments are included and the results show that the method can accurately detect the moving target in complex background.

To cope with the increasingly competitive and demanding markets, CNC machine tool company needs a new form of development that focuses on two core competency factors: ‘process’ and ‘knowledge’. This study presents a knowledge-centric process management framework for the CNC machine tool design and development (D&D) with the integration of process and knowledge. Requirements for the framework are generated based primarily on the nature of the machine tool design practice. The proposed framework consists of process integration model, process simulation, process execution and knowledge objects management modules. Each of these modules is elaborated to support the knowledge-centric machine tool development process management. Finally, the prototype development is presented. Results of this study facilitate the knowledge integration in CNC machine tool D&D, and thus increase machine tool development capability, reduce development cycle time and cost, and ultimately speed up the effectiveness and ensure the exc...

The origin and evolution of molecular mechanisms underlying the self-renewal and differentiation of spermatogonial stem cells (SSCs) are fundamental questions in stem cell biology as well as reproduction medicine. In mammals, glial cell line-derived neurotrophic factor (GDNF) is crucial for SSC self-renewal and maintenance. However, in nonmammals, the role of Gdnf in SSCs still remains unknown. In this study, we report that the two GDNF homologs from medaka fish (Oryzias latipes), namely OlGdnfa and OlGdnfb, can promote proliferation activity and retain the spermatogonial property of SG3, a spermatogonial cell line derived from adult medaka showing the intrinsic property of SSCs by self-renewal and differentiation potential during 2 years of culture. Cloning and sequencing led to the identification of two cDNA sequences as Olgdnfa and Olgdnfb, which are 780-nt and 744-nt in length for 253 and 245 amino acid residues, respectively. Both are homologs of mammalian GDNF and share over 45% identity with the other known vertebrate homologs. Importantly, in a well-defined condition, the recombinant proteins, OlGdnfa and OlGdnfb, can significantly promote the proliferative activity of SG3 cells and retain the spermatogonial gene expression pattern and alkaline phosphatase activity. Meanwhile, both of the two recombinant proteins can upregulate the mRNA expression level of bcl6b, one of the prominent GDNF-regulated genes involved in SSC self-renewal and maintenance in mammals. Taken together, our findings suggest that just like the mammalian counterpart, the nonmammalian Gdnfs might mediate the self-renewal and maintenance of SSCs; moreover, Bcl6b might be a conserved regulator in SSC self-renewal across vertebrate taxa. This study extends our knowledge of GDNF functions in SSC biology during evolution.

Effects of calcium addition and electromagnetic stirring on the microstructure of AZ91 magnesium alloy and refinement mechanism were investigated. The results show that calcium addition ranging from 0.1wt% to 0.3 wt% does not lead to formation of any new phases but cause the refi nement of as-cast microstructure.However, combined calcium alloying and electromagnetic stirring significantly decrease the grain size, change the morphologies of the β-Mg17Al12 phases,and reduce their volume percentage. The minimum grain size of AZ91 alloy is obtained in the case of the addition of 0.2 wt%Ca with exciting voltage of 100 V. The microstructural refi nement is attributed to the increase of the degree of undercooling and nucleation temperature of primary α-Mg phases on the basis of DTA analysis results.

In the present study, an antibody highly specific to the Nile tilapia (Oreochromis niloticus) Foxp3 was produced and characterized. Immunohistochemistry analysis indicates that Foxp3 was expressed in peripheral blood mononuclear cells (PBMC) and certain packed lymphocytes in particular, what's more, the percentage of Foxp3(+) cells among PBMC was 5.7 ± 2.0% (n = 5) in healthy adults and could be significantly up-regulated after phytohemagglutinin (50 μg/ml) stimulation in vitro at 6, 12 and 24 h, respectively. In the lymphoid tissues, such as the thymus, spleen and head kidney, Foxp3 expression was observed mainly in lymphocyte-like cells. Surprisingly, in the non-lymphoid organ stomach, Foxp3 was detected in epithelial-like cells within the mucosa. Our study demonstrates for the first time that Foxp3 protein expression occurs not only in hematopoietic cells of lymphoid organ systems but also non-hematopoietic cells of non-lymphoid organ in lower vertebrates such as the fish tilapia. The conserved expression pattern of Foxp3 at the protein and cellular levels implies that it might have conserved functions from fish to mammals.

This paper focuses on business service types and its impacts from the buyer’s perceptive. Based on the literature review, we classified the business service into operand resources based service and operant resources based service, and argue that different dimensions of business service have different effects on the customer perceived value and the buyer-supplier’s relationship link duration. With a large sample survey of companies in Chinese fine chemistry industry of 250 valid responses. The results show that customer perceived value in terms of economic value, relational/support value and technical/core value mediates the relationship between operant resource based service and link duration.

Effect of electromagnetic stirring on microstructure of AZ91-0.8%Ce magnesium alloy was investigated. The results show that electromagnetic stirring causes a change of morphology of α-Mg phase from coarse dendrites to fine rosette-like or spherical shape. Grain size is significantly refined within the range of input voltage 75–125 V, moreover, the optimum input voltage corresponded to the minimum value (64 μ m) of grain size is 125 V. Compared to the non-stirred condition, the amount of β-Mg17Al12 precipitate under the stirred condition obviously increases. The grain refinement of AZ91-0.8%Ce alloy is mainly attributed to multiplication of existing grains in the melt caused by forced fluid flow under electromagnetic stirring condition. Addition of 0.8% Ce results in the formation of ‘necking’ at secondary dendrite arm roots of α-Mg crystals, and consequently, it is helpful to increase the number of heterogeneous nucleation.

Collaborative manufacturing execution system (c-MES) is very important for manufacturing enterprises to realize informatization under the networked manufacturing environment. Production characteristics, typical production flow and collaborative management requirements of multi-workshop production in discrete manufacturing enterprise is analyzed. An architecture oriented to discrete manufacturing enterprises of c-MES is put forward. Main functions of c-MES and key technologies to realize c-MES are analyzed. Finally some system interfaces are introduced by a case study.