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Lightweight structures are ubiquitous in nature and extensively applied in high-end industries for load-bearing purpose. Parametric design is superior for its rapid generation of complex geometries controlled by user-specified parameters, thus has been increasingly explored in structural optimization. Conventional parametric design approaches for lightweight structure are primarily focus on size and shape, while the topology still requires lengthy iterative process. The major issues that hinder parametric control of topological design include singularity of the stress field and the lack of proper operators for discretized geometry. This paper introduced an implicit neural representation for parametric design of stress-oriented cellular structure, which exhibited great potential to resolve the aforementioned issues by harnessing the universal approximation and resolution invariant capability of a neural network. The structure was implicitly trained to smoothly align with the principal stress field of the input geometry under arbitrary loading condition. A tailored wave projection function together with morphological operators were employed for parametric control of the output cellular structure. The proposed framework enables the parametric design and fabrication of various cellular structures, resulting in enhanced load-bearing capacity compared to structures designed using conventional methods. This advancement opens up new possibilities for the effective design of lightweight structures.

Abstract Background Pseudorabies virus (PRV) causes substantial losses in the swine industry worldwide. Attenuated PRV strains with deletions of immunomodulatory genes glycoprotein E (gE), glycoprotein I (gI) and thymidine kinase (TK) are candidate vaccines. However, the effects of gE/gI/TK deletions on PRV-host interactions are not well understood. Methods To characterize the impact of gE/gI/TK deletions on host cells, we analyzed and compared the transcriptomes of PK15 cells infected with wild-type PRV (SD2017), PRV with gE/gI/TK deletions (SD2017gE/gI/TK) using RNA-sequencing. Results The attenuated SD2017gE/gI/TK strain showed increased expression of inflammatory cytokines and pathways related to immunity compared to wild-type PRV. Cell cycle regulation and metabolic pathways were also perturbed. Conclusions Deletion of immunomodulatory genes altered PRV interactions with host cells and immune responses. This study provides insights into PRV vaccine design.

The residual stress inside stock materials is a fundamental property related to the quality of manufactured parts in terms of geometric/dimensional stability and fatigue life. For large parts that must meet high-precision requirements, accurately measuring and predicting the residual stress field has been a major challenge. Existing technologies for measuring the residual stress field are either strain-based measurement methods or non-destructive methods with low efficiency and accuracy. This paper reports a new non-destructive method for inferencing the residual stress field based on deformation forces. In the proposed method, the residual stress field of a workpiece is inferred based on the characteristics of the deformation forces that reflect the overall effect of the unbalanced residual stress field after material removal operations. The relationship between deformation forces and the residual stress field is modeled based on the principle of virtual work, and the residual stress field inference problem is solved using an enforced regularization method. Theoretical verification is presented and actual experiment cases are tested, showing reliable accuracy and flexibility for large aviation structural parts. The underlying principle of the method provides an important reference for predicting and compensating workpiece deformation caused by residual stress using dynamic machining monitoring data in the context of digital and intelligent manufacturing.

Abstract Obtaining an accurate hot‐spot temperature of oil‐natural air‐natural (ONAN) transformer is important for evaluating its operation status and load capacity. To meet the overload requirement, the cooling fan is usually added to the operating ONAN transformer as the auxiliary cooling equipment. However, the hot‐spot temperature evaluation methods in this case lacked discussion currently. To address this issue, an improved hot‐spot temperature evaluation method for the ONAN transformer considering the thermal resistance on the air side of radiator was proposed in this paper. Subsequently, the calculation method for the key parameter of the improved method (the convective heat transfer coefficient on the air side of radiator) was conducted. The accuracy and superiority of the improved method compared with the IEEE loading guides were verified by the manufacturer's software. Finally, the maximum steady‐state load of the ONAN transformer with cooling fan was achieved by the improved method. The results indicate that for the case of non‐rated load, the improved method can provide a more accurate thermal evaluation of ONAN transformer under different cooling modes than the IEEE loading guides. The method proposed in this paper can provide a reference for selecting the cooling fan parameters and formulating the load control strategy of the ONAN transformer.

IntroductionPseudorabies virus (PRV) is a herpesvirus that can infect domestic animals, such as pigs, cattle and sheep, and cause fever, itching (except pigs), and encephalomyelitis. In particular, the emergence of PRV variants in 2011 have resulted in serious economic losses to the Chinese pig industry. However, the signaling pathways mediated by PRV variants and their related mechanisms are not fully understood.MethodsHere, we performed RNA-seq to compare the gene expression profiling between PRV virulent SD2017-infected PK15 cells and Bartha-K/61-infected PK15 cells.ResultsThe results showed that 5,030 genes had significantly different expression levels, with 2,239 upregulated and 2,791 downregulated. GO enrichment analysis showed that SD2017 significantly up-regulated differentially expressed genes (DEGs) were mainly enriched in the binding of cell cycle, protein and chromatin, while down-regulated DEGs were mainly enriched in ribosomes. KEGG enrichment analysis revealed that the pathways most enriched for upregulated DEGs were pathways in cancer, cell cycle, microRNAs in cancer, mTOR signaling pathway and autophagy-animal. The most down-regulated pathways of DEGs enrichment were ribosome, oxidative phosphorylation, and thermogenesis. These KEGG pathways were involved in cell cycle, signal transduction, autophagy, and virus-host cell interactions.DiscussionOur study provides a general overview of host cell responses to PRV virulent infection and lays a foundation for further study of the infection mechanism of PRV variant strain.

In this paper, an ultrathin layer of arrayed electromagnetic resonators is introduced on the CFRP laminate to form a meta-CFRP composite. It is quite an exciting and promising design, as the composite metamaterial not only inherits the advantages of the CFRP composite in mechanical performance but can also obtain on-demand microwave absorption properties rather than purely reflective as neat CFRP laminates. Here, several meta-CFRP samples have been prepared by a co-curing process. Near-perfect microwave absorption (i.e., S11 ≤ -10 dB) has been achieved in a series of situations such as under normal incidence and a constant polarization angle, under oblique incidence and an arbitrary polarization angle, and for a relative broadband microwave absorption (11.28 GHz ∼ 12.52 GHz). Moreover, the mechanical properties of the fabricated meta-CFRP samples, including tension, compression, bending, and shear, have also been investigated, which showed an increase of more than 680% compared with previous microwave absorbers. The present work provides a new idea for designing electromagnetic and mechanical dual functional materials, based on which many new materials, for example, strong materials with tunable microwave absorption, can be further developed in the future.

Abstract Initial residual stress is the main reason causing machining deformation of the workpiece, which has been deemed as one of the most important aspects of machining quality issues. The inference of the distribution of initial residual stress inside the blank has significant meaning for machining deformation control. Due to the principle error of existing residual stress detection methods, there are still challenges in practical applications. Aiming at the detection problem of the initial residual stress field, an initial residual stress inference method by incorporating monitoring data and mechanism model is proposed in this paper. Monitoring data during machining process is used to represent the macroscopic characterization of the unbalanced residual stress, and the finite element numerical model is used as the mechanism model so as to solve the problem that the analytic mechanism model is difficult to establish; the policy gradient approach is introduced to solve the gradient descent problem of the combination of learning model and mechanism model. Finally, the initial residual stress field is obtained through iterative calculation based on the fusing method of monitoring data and mechanism model. Verification results show that the proposed inference method of initial residual stress field can accurately and effectively reflect the machining deformation in the actual machining process.

BackgroundPorcine epidemic diarrhea virus (PEDV), an intestinal pathogenic coronavirus, has caused significant economic losses to the swine industry worldwide. At present, there are several treatment methods, but there is still a lack of clinically effective targeted drugs, new antiviral mechanisms and drugs need to be explored.MethodsIn this study, we established a model of erastin versus ferrostatin-1 treatment of Vero cells, and then detected virus proliferation and gene expression by RT-qPCR through PEDV infection experiments.ResultsWe demonstrated for the first time that erastin significantly inhibited the replication of PEDV upon entry into cells; Vero treated with erastin significantly regulated the expression of three genes, NRF2, ACSL4 and GPX4, notably erastin regulated the expression of these three genes negatively correlated with the expression induced by PEDV virus infection.ConclusionsSince NRF2, ACSL4 and GPX4 are classical Ferroptosis genes, this study speculates that erastin may inhibit the replication of PEDV in Vero cells in part through the regulation of ferroptosis pathway, and erastin may be a potential drug for the treatment of PEDV infection.

Temperature-dependent electromagnetic properties are not only closely related to the manufacturing process of carbon fiber reinforced polymer (CFRP) components, e.g., curing of CFRP composites using microwaves, but also directly determines some key performance indicators of CFRP structures like electromagnetic stealth and anti-electromagnetic interference (EMI). In this paper, we proposed a resistance heating assisted free space method to measure the temperature-dependent electromagnetic properties of both CFRP materials and structures. On this basis, the temperature-dependent electromagnetic properties of a unidirectional carbon fiber/PEEK composite material were measured in the temperature range from room temperature to 400 °C. Moreover, the temperature-dependent electromagnetic properties of a CFRP structure, i.e., a multidirectional carbon fiber/PEEK laminate covered by subwavelength resonance structures, were also measured. The results indicated that temperature has a significant effect on the electromagnetic properties of both CFRP materials and structures. Our work provides a simple and practical solution to measure the temperature-dependent electromagnetic properties of CFRP materials and structures.

Porcine epidemic diarrhea virus (PEDV) is a highly contagious coronavirus that induces diarrhea and death in neonatal piglets, resulting in substantial economic losses to the global swine industry. The mechanisms of PEDV infection and the roles of host factors are still under exploration. In this study, we used the ferroptosis pathway downstream target activator (1S,3R)-RSL3 compound as a starting point, combined with the interactions of N-acetylcysteine and deferoxamine, to elucidate the effects of a series of compounds on PEDV proliferation. We also established glutathione peroxidase 4 (GPX4) gene overexpression to further elucidate the relationship between the ferroptosis pathway and PEDV. (1S,3R)-RSL3 inhibited PEDV replication in Vero cells, while N-acetylcysteine and deferoxamine promoted its proliferation. In addition, (1S,3R)-RSL3 mainly affected the replication stage of PEDV. Overexpression of GPX4 promoted PEDV proliferation, indicating that the ferroptosis pathway could influence PEDV replication in Vero cells. This study focused on the mechanism of (1S,3R)-RSL3 inhibition on PEDV, laying the foundation for exploring the pathogenic mechanisms of PEDV and drug development.

This study sought to evaluate a novel approach for automatic coregistration of optical coherence tomography (OCT) and coronary angiography. Lumen diameters and side branches from both coronary angiography and OCT were used to create 2 feature sets. Subsequently, a 2-step coregistration approach was performed on the feature sets for matching of each OCT cross section on the angiographic centerline. For validation, all side branches with ≥1.0 mm diameter were identified and used as paired fiduciary landmarks. Geographical error was defined as the distance between the automatically coregistered and the true-paired landmarks. Altogether 212 vessels from 181 patients were analyzed. Mismatch of coronary angiography and OCT occurred in 64 of 1,530 reference landmarks. Median geographical error was 0.32 (interquartile range: 0.00-0.56) mm. The mean time for coregistration was 20.69 ± 1.07 seconds. In conclusion, fast and automatic coregistration of OCT and angiography using a single standard angiographic loop is feasible and accurate.

Abstract The rapidly increasing demand and complexity of manufacturing process potentiates the usage of manufacturing data with the highest priority to achieve precise analyze and control, rather than using simplified physical models and human expertise. In the era of data-driven manufacturing, the explosion of data amount revolutionized how data is collected and analyzed. This paper overviews the advance of technologies developed for in-process manufacturing data collection and analysis. It can be concluded that groundbreaking sensoring technology to facilitate direct measurement is one important leading trend for advanced data collection, due to the complexity and uncertainty during indirect measurement. On the other hand, physical model-based data analysis contains inevitable simplifications and sometimes ill-posed solutions due to the limited capacity of describing complex manufacturing process. Machine learning, especially deep learning approach has great potential for making better decisions to automate the process when fed with abundant data, while trending data-driven manufacturing approaches succeeded by using limited data to achieve similar or even better decisions. And these trends can demonstrated be by analyzing some typical applications of manufacturing process.

Aero-engine casing is a kind of thin-walled rotary part for which serious deformation often occurs during its machining process. As deformation force is an important physical quantity associated with deformation, the utilization of deformation force to control the deformation has been suggested. However, due to the complex machining characteristics of an aero-engine casing, obtaining a stable and reliable deformation force can be quite difficult. To address this issue, this paper proposes a deformation force monitoring method via a pre-support force probabilistic decision model based on deep autoregressive neural network and Kalman filter, for which a set of sophisticated clamping devices with force sensors are specifically developed. In the proposed method, the pre-support force is determined by the predicted value of the deformation force and the equivalent flexibility of the part, while the measurement errors and the reality gaps are reduced by Kalman filter via fusing the predicted and measured data. Both computer simulation and physical machining experiments are carried out and their results give a positive confirmation on the effectiveness of the proposed method. The results are as follows. In the simulation experiments, when the confidence is 84.1%, the success rate of deformation force monitoring is increased by about 30% compared with the traditional approach, and the final impact of clamping deformation of the proposed method is less than 0.003 mm. In the real machining experiments, the results show that the calculation error of deformation by the proposed method based on monitoring the deformation force is less than 0.008 mm.

Naphthalimides, such as amonafide and mitonafide in clinical trials, have been developed as antitumor agents for orthotopic tumor. However, the serious side effects in cancer patients limit their applications. Herein, a new class of polyamine-based naphthalimide conjugates 5a-5c, 7a-7b, and 11a-11b with and without the alkylation of the distant nitrogen in the polyamine chain were synthesized and the mechanism was determined. Compared with amonafide, dinitro-naphthalimide conjugate 5c with a 4,3-cyclopropyl motif preferentially accumulates in cancer cells and minimizes side effects in vitro and in vivo. More importantly, 5c at the dosage of as low as 3 mg/kg (57.97%) displays better antitumor effects than the positive control amonafide (53.27%) at 5 mg/kg in vivo. And a remarkably elevated antitumor activity and a reduced toxicity are also observed for 5c at 5 mg/kg (65.90%). The upregulated p53 and the apoptotic cells (73.50%) indicate that the mechanism of 5c to induce apoptosis may result from its enhanced DNA damage. Further investigation indicates that in addition to target DNA, 5c can modulate the polyamine homeostasis by upregulating polyamine oxidase (PAO) in a different way from that of amonafide. And also by targeting PTs overexpressed in most of cancer cells, 5c downregulates the contents of Put, Spd, and Spm, which are in favor of suppressing fast-growing tumor cells. Our study implies a promising strategy for naphthalimide conjugates to treat hepatic carcinoma with notable activities and reduced toxicities at a low dosage.

Abstract For thin-walled parts, uniform allowance to each machining surface is allocated by the traditional machining method. Considering the sequence of the adjacent machining features, it may cause poor stiffness for some side walls due to a minor wall thickness, which may cause the deformation of the final formed parts to be large, or deduce machining efficiency for some machining features due to too thick remains. In order to address this issue, a non-uniform allowance allocation method based on interim state stiffness of machining features for the finishing of thin-walled structural parts is proposed in this paper. In this method, the interim state model of machining features is constructed according to the machining sequence of the parts, and the stiffness of the side wall is taken as the evaluation index to allocate reasonable allowance value to the corresponding machining surface to ensure the stiffness requirement of the parts in the machining process. According to the finite element simulation results, the non-uniform allowance allocation method proposed in this paper can effectively improve the stiffness of the parts and reduce the deformation of the parts, when compared with the traditional uniform allowance machining method.

Physiological characteristics of human malignancies are increased glycolysis and overexpression of glucose transporters (GLUTs). 18Flurodeoxyglucose-positron emission tomography (FDG-PET) has successfully developed as clinical modality for the diagnosis and staging of many cancers based on the Warburg effect. To leverage this glucose transporter mediated metabolic disparity between normal and malignant cells, in the current report, protected, and de-protected glucose, mannose, galactose, rhamnose, maltose, and lactose-conjugated platinum(IV) complexes were designed and synthesized. The suggested potential of facilitated intravenous to oral switching of glycosylated platinum(IV) prodrugs with cancer-targeting properties were evaluated for glucose transporter 1 (GLUT1) and organic cation transporter 2 (OCT2)-mediated selective properties in vitro and in vivo. The cytotoxicity of 2d, 5d, and 6d were ~23-fold greater than that of the positive controls cisplatin, oxaliplatin, and satraplatin, respectively. The leading compound 6d, the IC50 of which with the GLUT1 inhibitor 4,6-oethylidene-α-D-glucose (EDG) and phloretin (31.80 and 38.71 μM) are 36- and 44-folds higher, respectively, than the 48 h IC50 (0.89 μM), is superior to the reported 5-8, exhibiting enhanced cancer targeting. The compounds also showed reduced toxicity to normal cells (293T IC50 = 12.06 μM and 3T3 cells IC50 > 100 μM) and exhibited no cross-resistance to cisplatin. Moreover, the encouraging selectivity of 6d for MCF-7 cells in vivo indicated that the pyranoside performs an important function in cancer targeting.

BACKGROUND: The FORZA trial (FFR or OCT Guidance to Revascularize Intermediate Coronary Stenosis Using Angioplasty) prospectively compared the use of fractional flow reserve (FFR) or optical coherence tomography (OCT) for treatment decisions and percutaneous coronary intervention (PCI) optimization in patients with angiographically intermediate coronary lesions. Murray law-based quantitative-flow-ratio (μQFR) is a novel noninvasive method for the computation of FFR. In the present study, we evaluated the clinical impact of μQFR, FFR, or OCT guidance in FORZA trial lesions at 3-year follow-up. METHODS: μQFR was assessed at baseline and, in the case of a decision to intervene, after (FFR- or OCT-guided) PCI. The baseline μQFR was considered the final μQFR for deferred lesions, and post-PCI μQFR value was taken as final for stented lesions. The primary end point was target vessel failure ([TVF]; cardiac death, target-vessel-related myocardial infarction, and target-vessel-revascularization) at a 3-year follow-up. RESULTS: A total of 419 vessels (199 OCT-guided and 220 FFR-guided) were included in the FORZA trial. μQFR was evaluated in 256 deferred lesions and 159 treated lesions (98 OCT-guided PCI and 61 FFR-guided PCI). In treated lesions, post-PCI μQFR was higher in OCT-group compared with FFR-group (median, 0.93 versus 0.91; P=0.023), and the post-PCI μQFR improvement was greater in FFR-group (0.14 versus 0.08; P<0.0001). At 3-year follow-up, OCT- and FFR-guided treatment decisions resulted in comparable TVF rate (6.7% versus 7.9%; P=0.617). Final μQFR was the only predictor of TVF. μQFR ≤0.89 was associated with 3 x increase in TVF (11.6% versus 3.7%; P=0.004). PCI was a predictor of higher final μQFR (odds ratio, 0.22 [95% CI, 0.14-0.34]; P<0.001). CONCLUSIONS: In vessels with angiographically intermediate coronary lesions, OCT-guided PCI resulted in comparable clinical outcomes as FFR-guided PCI. μQFR estimated at the end of diagnostic or interventional procedure predicted 3-year TVF. [ABSTRACT FROM AUTHOR]

With the increase of power load, the overheating problem of oil-immersed transformer in operation cannot be ignored. Therefore, it is necessary to propose reasonable heat dissipation enhancement measure for oil-immersed transformer in operation and study the influence of the measure on the internal temperature of transformer. The heat transfer process of oil-immersed transformer is analyzed, and the air-side heat transfer coefficient is pointed out to be the important parameter limiting the heat dissipation capacity of the transformer. In order to improve heat dissipation capacity, the measures based on cooling fans and falling film are proposed and the calculation methods for the air-side heat transfer coefficient are conducted, respectively. Moreover, the top-oil temperature and hot-spot temperature under two measures are compared by the thermal-fluid coupling model of oil-immersed transformer. For the transformer operating at rated load and the ambient temperature of 25 °C, after the cooling fans are adopted, the top-oil temperature and hot-spot temperature can be reduced by 22.4 °C and 20.7 °C, while after the falling film is adopted, the top-oil temperature and hot-spot temperature can be reduced by 31.2 °C and 28.7 °C, respectively. The results show that the falling film is a more effective heat dissipation enhancement measure, which can meet the higher load demand of oil-immersed transformer. [ABSTRACT FROM AUTHOR]

Online medical platforms have emerged as a popular means for patients to access high-quality medical services efficiently. These platforms offer a variety of services, including paid consultations and free consultations. Given that doctors can increase their revenue through these platforms, researchers should investigate how to improve patients’ willingness to pay for these services. Drawing upon social exchange theory, stimulus-organism-response theory, and the information systems (IS) success model, this study proposes a model and five hypotheses to examine the influence of free medical consultations on patients’ willingness to buy paid services. To test these hypotheses, a questionnaire survey was conducted, and the collected data were analyzed using the structural equation model. The results indicate that the quality of information and services provided by doctors during free consultations positively affects patients’ willingness to pay. By introducing information quality and service quality into the IS success model in the context of free medical consultations, this study contributes to the literature on online medical platforms and expands our understanding of patients’ behavior. The findings of this study can be useful for online medical platforms and doctors to design effective platform functions and individual behavioral strategies.

Pocket milling has long been a popular means for machining pocket features in structural parts and skins in the aviation industry. Recent advanced milling technologies pose new challenges for pocket milling path which existing contour-parallel path generation schemes cannot overcome. For high-speed machining, pocket milling path is desired to be smooth and with no tool retractions during the process, while the path stepover should be kept within a prescribed range to achieve relatively constant cutting load. These geometric constraints are also vital in the application of aircraft skin mirror milling in order to guarantee a correct and consistent thickness signal reception for real-time adjustment of the process. Traditional path optimization based on local modification can only meet a few of these constraints while others are being violated. Therefore, we propose a novel contour-parallel path generation scheme that respects all these process constraints by utilizing the idea of image morphology. The two-step scheme first generates an initial path by propagating from the rectified medial curve of the pocket shape. The initial path is then treated as a binary image being iteratively deformed and projected back into the pocket region via quadratic optimization. Experimental results show that our developed scheme can generate a smooth, tool retraction free and stepover-guaranteed path for various shapes of pocket. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced plastics have been widely applied in aircraft structures, which require more rapidly repairing process when carbon fiber reinforced plastics structures are damaged. A novel method of self-resistive electrical heating to rapidly repair carbon fiber reinforced plastics parts was investigated, which utilizes the electrical current passing through the carbon fiber to generate heat and directly cure the whole carbon fiber reinforced plastics patches. A portable self-resistive electrical repairer with automatic temperature control unit was developed. Repair experiments of self-resistive electrical and the electrical blanket heating were conducted, in which the heating temperature distribution field was observed by the thermal infrared imager. The degree of cure of different samples was characterized, and the cross-section morphology and void content of different samples were assessed. Flexural and inter-laminar shear tests were carried out. The experiment results showed that the flexural and interlaminar shear strength recovery ratio of self-resistive electrical repaired samples attained to 85.48% and 65.89%, which was the same or even slightly higher level as the blanket repairing process, but only cost 62% repairing period and 58% repairing energy of the later one. Finally, from the experimental results, the heat transfer behavior of different processes was analyzed. [ABSTRACT FROM AUTHOR]

Three new sandwich-type organophosphonate-functionalized polyoxotungstate clusters, [{Ni(H2O)5}x(AsW6O21)2{Ni(OOCCH2NCH2PO3)2}3] (x = 0 (Ni1), 1 (Ni2 and Ni3)), were successfully isolated via a "top-down" synthetic strategy. Compounds (Ni1-Ni3) were characterized by single crystal X-ray analysis, X-ray powder diffraction (XRPD), IR spectroscopy, UV-vis spectroscopy, and thermogravimetric analyses (TGA). Magnetic properties provide evidence for antiferromagnetic coupling in Ni2 and Ni3 and ferromagnetic interaction in Ni1. Catalytic studies of the three polyoxotungstates for the oxidation of allylic alcohols to epoxides have been investigated in water with H2O2 as the oxidant. All three polyoxotungstates exhibit efficient catalytic performance with excellent conversion and high selectivity at room temperature. [ABSTRACT FROM AUTHOR]

In a typical multi-pass machining process of freeform surfaces, especially at the roughing stage, the constant Z level strategy is typically used. Under this strategy, the inevitably formed islands where the tool has to travel between increase the machining time as the tool has to air-cut between them. Moreover, the uneven intermediate geometry left on the islands leads to sharp changing of chip load and jeopardizes the finish surface quality. To avoid the staircase-like intermediate geometry of the islands and most of all for the ultimate goal of maximizing the machining efficiency, in this paper we present a method of variable-depth of cut multipass tool path generation for multi-axis machining of mesh surfaces. By parameterizing the cut volume to a unit uvw cubic parametric domain, the multi-pass process planning task turns to finding an optimal sequence of w level parameters. To solve the optimization problem, we introduce a machining efficiency indicator--the average material removal rate (AMRR). The w level parameters are obtained by iteratively solving the maximization problem regarding AMRR. The preliminary computer simulation and real physical cutting experiments show that substantial savings in total machining time could be achieved by the proposed method as compared to the traditional constant Z level method. [ABSTRACT FROM AUTHOR]

Service provider (SP) know-hows are essential in machining service (MS) encapsulation in the cloud. However, since the acquisition of the know-hows for complex parts machining requires investing considerable manpower and resources in R&D, this kind of machining know-hows is usually considered as one of the core competences of the SP who makes them unshareable. Targeting the problem, this paper presents a new cloud manufacturing (CM) architecture in which MSs are encapsulated within each SP with standardized machining task description strategies (SMTDS). Only the capability information about what the SP can do is provided to the cloud. During service matching, SMTDS is also applied for user request formulation to improve the matching efficiency and quality. For complex parts in large size, high machining requirements, high value, short delivery cycle, and complex structures, e.g., aircraft structural parts, unacceptable machining quality or delivery delay may cause a much greater loss not only in economy. In the proposed CM architecture, to guarantee the feasibility of the MSs for complex structural parts, machining operations for the user preferred services could be generated by mapping the corresponding typical machining plans (TMP) to the part based on the dynamic feature concept to support accurate evaluations of the MSs. The machining of an aircraft structural part is then applied as a test user request to demonstrate how the proposed method works for finding MS for complex parts. [ABSTRACT FROM AUTHOR]

Abstract Background Grifolic acid is a derivative of grifolin, an antitumor natural compound, and it was reported as an agonist of free fatty acid receptor GPR120. Little is known about its antitumor effects and the involvement of GPR120. Methods GH3 cells, the rat anterior pituitary adenoma cells, were cultured and the cell death was measured by MTT assay and Annexin V/PI staining. The mitochondrial membrane potential (MMP) of GH3 cells was measured by JC-1 staining. Cellular ATP levels and the intracellular NAD/NADH ratio were measured. GPR120 expression in GH3 cells was observed by RT-PCR and Western Blot, and siRNA was used to inhibit GPR120 expression in GH3 cells. Results Grifolic acid dose- and time-dependently induced the necrosis of GH3 cells. Grifolic acid significantly reduced the mitochondrial membrane potential (MMP) and decreased cellular ATP levels in GH3 cells. In contrast, the MMP of isolated mitochondria was not decreased by grifolic acid. The intracellular NAD/NADH ratio was significantly increased by grifolic acid. GPR120 is expressed in GH3 cells, but GPR120 agonists such as EPA, GW9508 and TUG891 did not affect the viability of GH3 cells. Moreover, GPR120 siRNA knockdown showed no significant influence on grifolic acid-induced GH3 cell death. Conclusion Grifolic acid induces GH3 cell death by decreasing MMP and inhibiting ATP production, which may be due to the inhibition of NADH production through a GPR120-independent mechanism.

In this study, TiC-Al _2 O _3 /Al ribbons inoculant were prepared by mechanical alloying, spark plasma sintering (SPS) and melt spinning. Adding 5vol.% TiC-Al _2 O _3 /Al ribbons to an Al–Si–Mg–Ti (ASMT) alloy melt significantly refined the α -Al grains from 28.5 μ m to 14.9 μ m. In addition, the morphology of the eutectic silicon were modified and optimized, changing from needle-like silicon to spherical silicon. Adding the TiC-Al _2 O _3 /Al ribbons significantly improved the mechanical properties of TiC-Al _2 O _3 /Al–Si–Mg–Ti (TAASMT) alloy, including its elastic modulus (EM), yield strength (YS), ultimate tensile strength (UTS) hardness, and elongation which were increased by 5.4%, 18.4%, 32.7%, 8.3%, and 62.3%, respectively. These increases in the mechanical properties could be attributed to the intracrystalline reinforcement of the Al _2 O _3 and TiC nanoparticles, well-bonded particle/matrix interface, modification of the eutectic silicon phases, and synergistic effects of the Orowan strengthening, Coefficient of thermal expansion (CTE) mismatch strengthening, load transfer, grain refining strengthening, and geometrically necessary dislocations (GND) strengthening.

In airplane research and development, tooling design is desired to be undertaken with airplane product design concurrently together with the considerations of downstream processes such as manufacturing and assembling. However, so far, collaborative design for aircraft tooling, especially in large-sized one, is difficult. To solve this, a self-adaptive collaborative design method of aircraft tooling based on a natural neuron-endocrine-immunity system, multi-agent and product data management (PDM) technologies has been developed and is presented in this article. Firstly, with the similar working principle of the neuron-endocrine-immunity system model that is able to manage cells and tissues of a human body in a self-adaptive means, a tooling collaborative design model has been developed to enhance the responsiveness and adaptability for changes during aircraft design. Secondly, a collaborative design framework has been proposed by applying the multi-agent and PDM technologies to implement this model. The multi-agent technology focuses on managing the frequent changes, and the PDM has been used to manage the mass aircraft product design and tooling. This framework incorporates the PDM Client/Server architecture and adopts a federated structure for effective collaboration in terms of unified data sharing, convenient tool wrapping, decentralized control, coordination, etc. Finally, a multi-agent-based prototype system, developed, and testified in an aircraft manufacturing enterprise, is demonstrated for aircraft tooling collaborative design. Case studies show that optimized and re-configurable aircraft tooling design can be achieved with the help of the developed collaboration framework. [ABSTRACT FROM AUTHOR]

Focuses on variations in extensible markup languages (XML) management systems. Background on the development of XML; Differences between XML-enabled databases and native XML databases; Suggestions for useful XML databases. INSETS: Current XML Management Products;Related W3C Documents.

Heck reaction catalyzed by cobalt hollow nanospheres has been developed; the coupling of alkenes with aryl iodide or aryl bromide in the presence of potassium carbonate provides the corresponding products with moderate to good yields, which reveals obvious advantages such as low-cost catalyst, ligand-free condition, the recyclability of the catalyst and simple experimental operation. [ABSTRACT FROM AUTHOR]